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[studies of complex lipids. synthesis of ionophore derivatives of diphosphatidylglycerol (cardiolipin)].synthesis of cardiolipin analogues containing an ionophore residue in the fatty acid moiety is described. the ionophore, dibenzo-18-crown-6, has been incorporated into second position of the glycerol residue by acylating mono- and dilysocardiolipin with a modified fatty acid anhydride. lyso-derivatives of cardiolipin have been prepared by enzymatic hydrolysis of beef heart cardiolipin by snake venom phospholipase a2 (naja naja oxiana).20113219123
evaluation of venom extracts from the cobra snakes (naja naja) of three different weights and size groups. 20103100829
evidence for existence of venom 5' nucleotidase in multiple forms through inhibition of concanavalin a.pharmacologically active 5' nucleotidase is a ubiquitously distributed enzyme in snake venoms. in this study the effect of concanavalin a (con-a) on different snake venoms 5' nucleotidase activity is tested in order to know the protein nature which will ultimately help in purification of the enzyme with high yield. con-a inhibited naja naja, naja kauthia, naja melanoleuca, naja naja sputatrix, agistrodon halys blomhoffii, bothrops asper and oxyranus scutellas venom 5' nucleotidase activity at di ...201020941753
molecular diversity in venom proteins of the russell's viper (daboia russellii russellii) and the indian cobra (naja naja) in sri lanka.to examine the molecular diversity of the venom proteins of the russell's viper (daboia russellii russellii) and the indian cobra (naja naja) in sri lanka, we isolated 38 venom proteins through a combination of anion exchange chromatography followed by reversed-phase high performance liquid chromatography. from the venom of d. r. russellii we isolated 15 proteins: 5 isozymes of phospholipase a(2) (pla(2)), 4 serine proteases, 2 c-type lectin-like proteins, 2 l-amino acid oxidases, 1 cysteine-ric ...201020203422
lipid domain formation modulates activities of snake venom phospholipase a(2) enzymes.the goal of the present study is to elucidate the effect of lipid domain formation on activities of naja naja atra and bungarus multicinctus phospholipase a(2) (pla(2)) enzymes. sphingomyelin inhibited enzymatic activity and membrane-damaging activity of pla(2) against egg yolk phosphatidylcholine (eypc), while cholesterol and cholesterol sulfate abrogated the inhibitory effect of sphingomyelin. the ability of cholesterol and cholesterol sulfate to abolish the inhibitory effect of sphingomyelin ...201020705082
interaction of naja naja atra cardiotoxin 3 with h-trisaccharide modulates its hemolytic activity and membrane-damaging activity.to address whether saccharide moieties of blood groups a, b and o antigens modulate hemolytic activity of naja naja atra cardiotoxins (ctxs), the present study was carried out. unlike other ctx isotoxins, hemolytic activity of ctx3 toward blood group o cholesterol-depleted red blood cells (rbcs) was notably lower than that of blood groups a and b cholesterol-depleted rbcs. conversion of blood group b rbcs into blood group o rbcs by alpha-galactosidase treatment attenuated the susceptibility for ...201020193704
inhibitory effect of tea polyphenols on local tissue damage induced by snake venoms.the methanolic extract of fresh tea leaves of camellia sinensis l. (theaceae) (cs) was assayed for its potential to inhibit enzymes with hydrolytic activity in naja naja kaouthia lesson (elapidae) and calloselasma rhodostoma kuhl (viperidae) venoms. these snake venom enzymes are responsible for the early effects of envenomation, such as local tissue damage and inflammation. the cs extract inhibited phospholipase a(2), proteases, hyaluronidase and l-amino acid oxidase in both venoms by in vitro n ...201019585481
anti-coagulant activity of a metalloprotease: further characterization from the indian cobra (naja naja) venom.a high molecular mass, non toxic metalloprotease the nn-pf3 with the bound ca(2+) and zn(2+) from the naja naja venom has been studied further for its anticoagulant property. the molecular mass by maldi-tof mass spectrometry was 67.81 kda. the nn-pf3 exhibited fibrin(ogen)olytic activity. in addition to fibrinogen, nn-pf3 hydrolyzed blood and plasma clot with the later hydrolyzed about one fold higher. the alpha polymer of fibrin was preferentially hydrolyzed over the alpha chain but the beta ch ...201019629641
systemic pathological effects induced by cobra (naja naja) venom from geographically distinct origins of indian peninsula.indian cobra (naja naja) venom from different geographical locations varied in its composition and biochemical, pharmacological and immunological properties. recently it has been shown that the variation in composition of venom from different geographical origin of indian peninsula is due to the quantitative difference in the same components and also the presence of different biochemical entities with respect to their origin. this disparity in venom composition may be due to several environmenta ...201019733040
genistein, a potent inhibitor of secretory phospholipase a2: a new insight in down regulation of inflammation.some of the legumes, spices and medicinal herbs rich in genistein are known for their anti-inflammatory properties. anti-inflammatory property of these herbs is determined by subjecting secretory phospholipase a(2) (spla(2)) inhibition, a key enzyme in the inflammatory reactions by genistein.201019894024
taiwan cobra phospholipase a2-elicited jnk activation is responsible for autocrine fas-mediated cell death and modulating bcl-2 and bax protein expression in human leukemia k562 cells.phospholipase a(2) (pla(2)) from naja naja atra venom induced apoptotic death of human leukemia k562 cells. degradation of procaspases, production of tbid, loss of mitochondrial membrane potential, bcl-2 degradation, mitochondrial translocation of bax, and cytochrome c release were observed in pla(2)-treated cells. moreover, pla(2) treatment increased fas and fasl protein expression. upon exposure to pla(2), activation of p38 mapk (mitogen-activated protein kinase) and jnk (c-jun nh(2)-terminal ...201019937732
down-regulation of the jak2/pi3k-mediated signaling activation is involved in taiwan cobra cardiotoxin iii-induced apoptosis of human breast mda-mb-231 cancer cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. exposure of mda-mb-231 cells with 0.03, 0.09, and 0.15 microm of ctx iii for 18 h, ctx iii-induced cell apoptosis, as evidenced by accumulation of sub-g1 population, externalization of phosphatidylserine, loss of mitochondrial membrane potential (deltapsim) with subsequent release of cytochrome c, and activation of both capases-9 and caspas ...201020144642
concomitant inactivation of the epidermal growth factor receptor, phosphatidylinositol 3-kinase/akt and janus tyrosine kinase 2/signal transducer and activator of transcription 3 signalling pathways in cardiotoxin iii-treated a549 cells.1. cardiotoxin (ctx) iii, a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has potential anticancer therapeutic activity. the aim of the present study was to investigate the apoptotic effect (and the underlying mechanism of action) of ctx iii in human adenocarcinoma a549 cells. 2. it was found that ctx iii induces apoptosis in a549 cells, as indicated by an increase in the sub-g(1) population, phosphatidylserine externalization, loss of mitochondrial membrane p ...201020456425
taiwan cobra cardiotoxin iii inhibits src kinase leading to apoptosis and cell cycle arrest of oral squamous cell carcinoma ca9-22 cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60-amino acid residues isolated from naja naja atra venom, has been reported to have cytotoxic activity. ctx iii exerted cytotoxicity with the s-phase cell cycle arrest, correlated with a marked decrease in the expression levels of cyclin a, cyclin b, and cyclin-dependent kinase 1 (cdk1), and apoptosis, accompanied with bax and bad up-regulation, and the down-regulation of bcl-2, p-bad, and x-linked inhibitor of apoptosis (xiap) with cytochrome ...201020493203
chemical modification of ascorbic acid and evaluation of its lipophilic derivatives as inhibitors of secretory phospholipase a(2) with anti-inflammatory activity.the halo 6-fatty acid esters of l-ascorbic acid 3a, 3b and 6-fatty acid esters of l-ascorbic acid 5a-g were achieved from l-ascorbic acid 1. compounds 3a, 3b and 5a-g were evaluated for anti-oxidant, anti-lipid peroxidation, and secretory phospholipase a(2) (spla(2)) inhibition in vitro, and spla(2) induced mouse paw edema. all the derivatives retained their anti-oxidant property compared to ascorbic acid at 6 × 10(-4)m and are good inhibitors of lipid peroxidation at 1 mg ml(-1) as evaluated by ...201020730622
prostatic involution after intraprostatic injection of cobra toxin.we evaluated the comparative effects of intraprostatic injection of cobra cardiotoxin d and botulinum toxin type a on prostate structure in the rat model.201020850839
the metalloprotease, nn-pf3 from naja naja venom inhibits platelet aggregation primarily by affecting α2β1 integrin.nn-pf3 is a non-toxic, anticoagulant, high-molecular-mass (67.81 kda) metalloprotease from indian cobra (naja naja) venom. in the present study, nn-pf3 was investigated for the mechanism of inhibition of collagen-induced aggregation of human platelets. the complete inhibition of collagen-induced aggregation and partial inhibition of adp- and epinephrine-induced aggregation has the respective ic(50) of 75 ± 5, 185 ± 10, and 232 ± 12 nm, whereas no inhibition of thrombin-, arachidonic acid-, and r ...201020957364
preparation and characterization of immunoglobulin yolk against the venom of naja naja atra.chinese cobra (naja naja atra) bite is one of the leading causes of snake-bite mortality in china. the traditional anti-cobra venom serum therapy was found to be expensive and with high frequency of side effects. therefore attempts were made to generate a high titer immunoglobulin from egg yolk (igy) of crude cobra-venom immunized leghorn hens, and to standardize an effective method for producing avian antivenom in relatively pure form. the igy was isolated first by water dilution method to remo ...201021341535
severe infection of wild-caught snakes with spirometra erinaceieuropaei from food markets in guangzhou, china involves a risk for zoonotic sparganosis.wild-caught snakes are a popular and traditional food in china. however, little known to the public, snakes are also intermediate hosts of spirometra erinaceieuropaei, a food- and water-borne pathogen of sparganosis. therefore, we investigated the prevalence of s. erinaceieuropaei in 10 popular species of wild-caught snakes in guangzhou city (guangdong province) between july 2009 and july 2010. one hundred and twenty-four specimens of 10 species (including enhydris plumbea, zoacys dhumnades, ela ...201021348631
acquired factor viii deficiency after consuming the dried gallbladder of a cobra, naja naja.acquired factor viii deficiency is very rare, often fatal. it is associated with pregnancy, autoimmune diseases, malignancy, and drugs, although no underlying cause is found in 50%. a 49-year-old male was referred with right shoulder bruising. the coagulation test showed a prolonged activated partial thromboplastin time. the factor viii level was less than 1%, and the factor viii inhibitor antibody titer was 246 bethesda units/ml. the findings were compatible with acquired factor viii deficiency ...201021120211
protective effects of hypothalamic proline-rich peptide and cobra venom naja naja oxiana on dynamics of vestibular compensation following unilateral labyrinthectomy.we tested the action of proline-rich peptide (prp-1) and cobra venom naja naja oxiana (nox) on deiters' nucleus neurons at 3rd, 15th and 35th days after unilateral labyrinthectomy (ul). early and late tetanic, post-tetanic potentiation and depression of deiters'neurons to bilateral high frequency stimulation of hypothalamic supraoptic and paraventricualar nuclei was studied. the analysis of spike activity was carried out by mean of on-line selection and special program. the complex averaged peri ...201020703940
molecular identification of three indian snake species using simple pcr-rflp method.three endangered indian snake species, python molurus, naja naja, and xenochrophis piscator are known to be significantly involved in illegal trade. effective authentication of species is required to curb this illegal trade. in the absence of morphological features, molecular identification techniques hold promise to address the issue of species identification. we present an effective pcr-restriction fragment length polymorphism method for easy identification of the three endangered snake specie ...201020384921
nonantibiotic properties of tetracyclines: structural basis for inhibition of secretory phospholipase a2.secretory phospholipase a(2) is involved in inflammatory processes and was previously shown to be inhibited by lipophilic tetracyclines such as minocycline (minotc) and doxycycline. lipophilic tetracyclines might be a new lead compound for the design of specific inhibitors of secretory phospholipase a(2), which play a crucial role in inflammatory processes. our x-ray crystal structure analysis at 1.65 a resolution of the minotc complex of phospholipase a(2) (pla(2)) of the indian cobra (naja naj ...201020211188
preparation of chitosan nanoparticles containing naja naja oxiana snake venom.hydrophilic nanoparticles have received much attention for delivery of therapeutic peptides, proteins, and antigens. chitosan (cs) is a biodegradable and nontoxic polysaccharide, as a carrier for drug delivery. the study purpose was to evaluate the influence of a number of factors on the encapsulation of naja naja oxiana (indian or speckled cobra) venom and loading capacity, as well as to investigate the physicochemical structure of nanoparticles. cs nanoparticles were produced based on the ioni ...201019616121
loop 3 of short neurotoxin ii is an additional interaction site with membrane-bound nicotinic acetylcholine receptor as detected by solid-state nmr spectroscopy.the contact area of neurotoxin ii from naja naja oxiana when interacting with the membrane-bound nicotinic acetylcholine receptor from torpedo californica was determined by solid-state, magic-angle spinning nmr spectroscopy. for this purpose, the carbon signals for more than 90% of the residues of the bound neurotoxin were assigned. differences between the solution and solid-state chemical shifts of the free and bound form of the toxin are confined to distinct surface regions. loop ii of the sho ...200919447114
epidemiology, clinical profile and management issues of cobra (naja naja) bites in sri lanka: first authenticated case series.in sri lanka, the spectacled cobra (naja naja) inflicts fatal bites. this hospital-based prospective study describes 25 cases of proven cobra bites, including 10 (40%) males and 15 (60%) females with a median age of 36 years (range 13-70 years). in 22 cases (88%) bites occurred in the daytime and in 13 cases (52%) they occurred at the victim's home compound. the site of the bite was the upper limb in 10 cases (40%), and 12 patients (48%) had applied a tourniquet. there were 5 dry bites (20%), 20 ...200919439335
consensus sequence l/pkssll mimics crucial epitope on loop iii of taiwan cobra cardiotoxin.phage display is effective in screening peptides that mimic venom's neutralizing epitopes. a phage display cyclized heptapeptide library (c7c library) was panned with purified divalent antivenin igg, which neutralizes naja naja atra venom (nav) and bungarus multicinctus venom (bmv). the selected heptapeptide sequences were aligned with known protein sequences of nav and bmv in genbank. one of the four consensus sequences, l/pkssll, mimicked the crucial epitope on loop iii of taiwan cobra cardiot ...200919632196
differential binding to phospholipid bilayers modulates membrane-damaging activity of naja naja atra cardiotoxins.to address the events that modulate membrane-damaging activity of naja naja atra cardiotoxins (ctxs), the present study was carried out. it was found that ctx isotoxins showed different activities in inducing leakage of vesicles made of egg yolk phosphatidylcholine (eypc)/dimyristoyl phosphatidic acid (dmpa) or eypc/egg yolk sphingomyelin (eysm). although ctxs had different gross conformations, the toxins showed similar binding affinity for phospholipid vesicles. topographical contact between to ...200919450618
jnk1/c-jun and p38 alpha mapk/atf-2 pathways are responsible for upregulation of fas/fasl in human chronic myeloid leukemia k562 cells upon exposure to taiwan cobra phospholipase a2.fas and fasl expression upregulation was found in human leukemia k562 cells upon exposure to naja naja atra phospholipase a(2) (pla(2)). pla(2) treatment induced an increase in intracellular ca(2+) ([ca(2+)]i) and ros generation levels, leading to activation of p38 mapk and jnk. suppression of both p38 mapk and jnk abrogated fas and fasl upregulation. unlike pla(2), catalytically inactive pla(2) treatment did not markedly increase fas and fasl protein expression, and p38 mapk activation was excl ...200919670268
membrane-bound conformation and phospholipid components modulate membrane-damaging activity of taiwan cobra cardiotoxins.membrane-damaging activity of naja naja atra cardiotoxin 3 (ctx3) on 1-palmitoyl-2-oleoyl-phosphatidylcholine (popc)/1,2-dimyristoyl-phosphatidic acid (dmpa) vesicles was approximately 3-fold that of n. naja atra cardiotoxin 4 (ctx4), while ctx3 and ctx4 displayed insignificantly permeabilizing activity in 1,2-dipalmitoyl-phosphatidylcholine (dppc)/dmpa vesicles. phospholipid-binding capability and oligomeric assembly upon binding with lipid vesicles did not closely correlate with membrane-damag ...200919673097
apoptosis of human hepatocellular carcinoma cell (hepg2) induced by cardiotoxin iii through s-phase arrest.cytotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, have potential therapeutic activity in tumor therapy. however, the therapeutic effect in solid tumor treatment with ctx iii are still largely unknown. in the present study, we investigated whether ctx iii affects cell growth and cell cycle progression of hepatocellular carcinoma cell (hepg2). we found that the proliferation of hepg2 cell was inhibited by ctx iii, to some extent, in a time ...200918986802
upregulation of fas and fasl in taiwan cobra phospholipase a2-treated human neuroblastoma sk-n-sh cells through ros- and ca2+-mediated p38 mapk activation.the aim of the present study is to elucidate the signaling pathway involved in death of human neuroblastoma sk-n-sh cells induced by naja naja atra phospholipase a(2) (pla(2)). upon exposure to pla(2), p38 mapk activation, erk inactivation, ros generation, increase in intracellular ca(2+) concentration, and upregulation of fas and fasl were found in sk-n-sh cells. sb202190 (p38mapk inhibitor) suppressed upregulation of fas and fasl. n-acetylcysteine (ros scavenger) and bapta-am (ca(2+) chelator) ...200919009558
anti-inflammatory activity of oleanolic acid by inhibition of secretory phospholipase a2.oleanolic acid, a triterpenoid known for its anti-inflammatory properties, is commonly present in several medicinal plants. the present study evaluated the effect of oleanolic acid on spla (2), a key enzyme in inflammatory reactions. oleanolic acid inhibited spla (2) activities of human synovial fluid (hsf), human pleural fluid (hpf) and vipera russelli (vrv-pl-v) and naja naja (nn-pl-i) snake venoms in a concentration-dependent manner. the ic (50) values of spla (2) from these sources ranged fr ...200919085684
catalytic activity-independent pathway is involved in phospholipase a(2)-induced apoptotic death of human leukemia u937 cells via ca(2+)-mediated p38 mapk activation and mitochondrial depolarization.in view of the controversial role of catalytic activity on the cytotoxicity of phospholipase a(2) (pla(2)), the present study is conducted to explore whether pla(2) induces apoptotic process of human leukemia u937 cells through catalytic activity-independent pathway. modification of his-48 (according to the sequence alignment with porcine pancreatic pla(2)) with p-bromophenacyl bromide (bpb) caused over 99.9% drop in enzymatic activity naja naja atra pla(2). it was found that bpb-pla(2)-induced ...200919118607
ros-mediated p38alpha mapk activation and erk inactivation responsible for upregulation of fas and fasl and autocrine fas-mediated cell death in taiwan cobra phospholipase a(2)-treated u937 cells.the aim of the present study is to explore the signaling pathway associated with naja naja atra phospholipase a(2) (pla(2))-induced apoptotic death of human leukemia u937 cells. degradation of procaspases, production of tbid, loss of mitochondrial membrane potential, and cytochrome c release were observed in pla(2)-treated cells. pla(2) treatment increased fas and fasl protein expression, and upregulated transcription of fas and fasl mrna. upon exposure to pla(2), ros generation, p38 mapk activa ...200919180563
the crystal structure of cobra venom factor, a cofactor for c3- and c5-convertase cvfbb.cobra venom factor (cvf) is a functional analog of human complement component c3b, the active fragment of c3. similar to c3b, in human and mammalian serum, cvf binds factor b, which is then cleaved by factor d, giving rise to the cvfbb complex that targets the same scissile bond in c3 as the authentic complement convertases c4bc2a and c3bbb. unlike the latter, cvfbb is a stable complex and an efficient c5 convertase. we solved the crystal structure of cvf, isolated from naja naja kouthia venom, ...200919368894
molecular docking studies and anti-enzymatic activities of thai mango seed kernel extract against snake venoms.the ethanolic extract from seed kernels of thai mango (mske) (mangifera indica l. cv. 'fahlun') (anacardiaceae) and its major phenolic principle (pentagalloyl glucopyranose) exhibited dose-dependent inhibitory effects on enzymatic activities of phospholipase a(2) (pla(2)), hyaluronidase and l-amino acid oxidase (laao) of calloselasma rhodostoma (cr) and naja naja kaouthia (nk)venoms by in vitro tests. the anti-hemorrhagic and anti-dermonecrotic activities of mske against both venoms were clearly ...200919384272
effects of cardiotoxin iii on nf-kappab function, proliferation, and apoptosis in human breast mcf-7 cancer cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. ctx iii-induced apoptosis in human breast mcf-7 cancer cells was confirmed by sub-g1 formation, phosphatidylserine (ps) externalization, and poly (adp-ribose) polymerase (parp) cleavage with an ic50 of 2 microg/ml at 48 h. effects of ctx iii on proliferation and apoptosis correlated with upregulation of bax, and downregulation of bcl-xl, bc ...200919408576
peripheral and spinal antihyperalgesic activity of najanalgesin isolated from naja naja atra in a rat experimental model of neuropathic pain.snake venoms are a rich source of various compounds that have applications in medicine and biochemistry. recently, it has been demonstrated that najanalgesin isolated from the venom of naja naja atra exerts analgesic effects on acute pain in mice. the objective of this study was to evaluate the antinociceptive effect of najanalgesin in a rat model of neuropathic pain, induced by l5 spinal nerve ligation and transaction. we observed that intraperitoneal (i.p.) administration of najanalgesin produ ...200919442704
inactivation of epidermal growth factor receptor and downstream pathways in oral squamous cell carcinoma ca9-22 cells by cardiotoxin iii from naja naja atra.cardiotoxin iii (1), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has potential therapeutic activity in cancer. treatment with 1 reduced phosphorylation of egfr and akt, as well as erk in ca9-22 cells. moreover, 1-treatment inhibited constitutive activation of stat3 and stat5 in a time-dependent manner. up-regulation of bax and down-regulation of anti-apoptotic proteins including bcl-2, bcl-x(l), and myeloid cell leukemia-1(mcl-1) were also found in cells t ...200919754129
vanillic acid as a novel specific inhibitor of snake venom 5'-nucleotidase: a pharmacological tool in evaluating the role of the enzyme in snake envenomation.vanillic acid has been investigated for its inhibitory effect on naja naja, daboia russellii, and trimeresurus malabaricus venom 5'-nucleotidase activity. trimeresurus malabaricus venom 5'-nucleotidase activity was 1.3- and 8.0-fold higher than that of n. naja and d. russellii venoms, respectively. substrate specificity studies showed that for all the venoms tested, 5'-amp was the preferred substrate for 5'-nucleotidase. this indicates the central role of adenosine in snake envenomation. vanilli ...200919961411
syndromic approach to treatment of snake bite in sri lanka based on results of a prospective national hospital-based survey of patients envenomed by identified snakes.of 860 snakes brought to 10 hospitals in sri lanka with the patients they had bitten, 762 (89%) were venomous. russell's vipers (daboia russelii) and hump-nosed pit vipers (hypnale hypnale) were the most numerous and h. hypnale was the most widely distributed. fifty-one (6%) were misidentified by hospital staff, causing inappropriate antivenom treatment of 13 patients. distinctive clinical syndromes were identified to aid species diagnosis in most cases of snake bite in sri lanka where the bitin ...200919815895
[isolation and pharmacological properties of analgesic fraction from venom of naja naja atra].to separate main analgesic fraction from venom of guangdong naja naja atra, to establish the basis for the using of naja naja atra and find new analgesic fraction.200919873725
anti-necrosis potential of polyphenols against snake venoms.polyphenols from the extracts of areca catechu l. and quercus infectoria oliv. inhibited phospholipase a(2), proteases, hyaluronidase and l-amino acid oxidase of naja naja kaouthia lesson (nk) and calloselasma rhodostoma kuhl (cr) venoms by in vitro tests. both extracts inhibited the hemorrhagic activity of cr venom and the dermonecrotic activity of nk venom by in vivo tests. the inhibitory activity of plant polyphenols against local tissue necrosis induced by snake venoms may be caused by inhib ...200919874222
purification and characterization of a myotoxic phospholipase a2 from indian cobra (naja naja naja) venom.a major phospholipase a2 (nn-xiii-pla2) which constitutes 20% of the whole naja naja naja venom was purified to homogeneity on cm-sephadex c-25 column chromatography. nn-xiii-pla2 is a basic protein with a mol. wt of 11,200 by sds-page. this enzyme has low enzymatic activity but is more toxic to mice than the whole venom. the ld50 value (i.p.) of nn-xiii-pla2 is 2.4 mg/kg body weight (whole venoms ld50 is 2.8 mg/kg body weight). it induces neurotoxic-like signs in experimental animals. it induce ...20092781585
isolation of a snake venom phospholipase a2 (pla2) inhibitor (aiplai) from leaves of azadirachta indica (neem): mechanism of pla2 inhibition by aiplai in vitro condition.a compound (aiplai (azadirachta indica pla(2) inhibitor)) purified from the methanolic leaf extract of a. indica (neem) inhibits the cobra and russell's viper venoms (rvvs) phospholipase a(2) enzymes in a dose-dependent manner. inhibition of catalytic and tested pharmacological properties of cobra venom (naja naja and naja kaouthia) pla(2) enzymes by aiplai is significantly higher (p<0.05) compared to the inhibition of pla(2) enzymes of crude rvv (daboia russelli) when tested under the same cond ...200818466944
new biological activity against phospholipase a2 by turmerin, a protein from curcuma longa l.turmerin is a protein from turmeric (curcuma longa l.) with a relative molecular mass of 14 kda. the protein inhibits the enzymatic activity and neutralizes the pharmacological properties, such as cytotoxicity, oedema and myotoxicity of multitoxic phospholipase a2 (nv-pla2) of cobra (naja naja) venom at a 1:2.5 molar ratio of nv-pla2:turmerin. a lineweaver-burk plot indicates that turmerin follows a linear mixed type of inhibition.200818177267
the structural and functional contribution of n-terminal region and his-47 on taiwan cobra phospholipase a2.modification of his-47 and removal of the n-terminal octapeptide caused a different effect on the structure of naja naja atra (taiwan cobra) phospholipase a2 (pla2). unlike native enzyme, ca2+ induced an alteration in the structural flexibility of his-modified pla2. moreover, the spatial positions of trp residues in his-modified pla2 were not properly rearranged toward lipid-water interface in the presence of ca2+. cd spectra and fluorescence measurement showed that the dynamic properties of trp ...200818008383
mutations on the n-terminal region abolish differentially the enzymatic activity, membrane-damaging activity and cytotoxicity of taiwan cobra phospholipase a2.to examine the functional contribution of the n-terminal region to the activities of naja naja atra phospholipase a(2) (pla(2)), studies on three n-terminally mutated pla(2) were carried out in the present work. removal of n-terminal heptapeptide caused a complete loss of membrane-damaging activity, whilst the mutants with an extra met before asn-1 or substituting asn-1 with met still retained approximately 40.9% and 82.9% membrane-damaging activity of the native enzyme, respectively. mutations ...200818022206
taiwan cobra cardiotoxins induce apoptotic death of human neuroblastoma sk-n-sh cells mediated by reactive oxygen species generation and mitochondrial depolarization.although naja naja atra cardiotoxin 3 (ctx3) and cardiotoxin 4 (ctx4) showed different cytotoxicity toward human neuroblastoma sk-n-sh cells, the two toxins induced apoptotic death on sk-n-sh cells. the apoptosis signals of ctx3 and ctx3 included ros generation, increase in mitochondrial permeability transition, cytochrome c release to the cytosol and activation of caspase-9 and -3. however, ctx3 quickly induced the effects with higher magnitude compared with ctx4. ros production and subsequent ...200818221763
l-amino acid oxidase from naja naja oxiana venom.a new l-amino acid oxidase (laao) was isolated from the central asian cobra naja naja oxiana venom by size exclusion, ion exchange and hydrophobic chromatography. the n-terminal sequence and the internal peptide sequences share high similarity with other snake venom l-amino acid oxidases, especially with those isolated from elapid venoms. the enzyme is stable at low temperatures (-20 degrees c, -70 degrees c) and loses its activity by heating at 70 degrees c. specific substrates for the isolated ...200818294891
involvement of both endoplasmic reticulum- and mitochondria-dependent pathways in cardiotoxin iii-induced apoptosis in hl-60 cells.cardiotoxin (ctx) iii, a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. in the present study, we investigated the mechanisms underlying the anticancer activity of ctx iii in human leukaemia (hl-60 cells). cardiotoxin iii activated the endoplasmic reticulum (er) pathway of apoptosis in hl-60 cells, as indicated by increased levels of calcium and glucose-related protein 78 (grp78), and triggered the subsequent activa ...200818505440
cardiotoxin iii-induced apoptosis is mediated by ca2+-dependent caspase-12 activation in k562 cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. when k562 cells were treated with ctx iii, cytosolic calcium concentration was rapidly and persistently increased. this ctx iii-induced cell death was partially reversed by pretreatment with bapta/am (20 microm), a chelator of intracellular ca2+. moreover, ctx iii-induced apoptotic signals, such as caspase-12 and c-jun n-terminal kinase (jn ...200818561336
p38 mapk activation and mitochondrial depolarization mediate the cytotoxicity of taiwan cobra phospholipase a2 on human neuroblastoma sk-n-sh cells.modification of catalytic residue his-47 with p-bromophenacyl bromide (bpb) abolished the enzymatic activity of naja naja atra phospholipase a2 (pla2). additionally, alterations in the global structure and the spatial positions of trp residues were noted in his-modified pla2. the cell viability of human neuroblastoma sk-n-sh cells was decreased by approximately 40% and 20% after treatment with 10 microm pla2 and bpb-pla2, respectively. native and his-modified pla2 induced a necrotic cell death a ...200818582542
neutralization of the pharmacological effects of cobra and krait venoms by chicken egg yolk antibodies.five-month-old white leghorn chickens were immunized with 50 microg of common cobra (naja naja) and 30 microg of krait venoms (bungarus caeruleus) to generate antivenom antibodies against the venom antigen. chickens received booster doses of increasing concentrations of venom at 14 days time intervals to raise the antivenom level in egg yolk. the antivenom from immunized chicken egg yolk was extracted by polyethylene glycol (peg) and ammonium sulphate precipitation method which was further purif ...200818590753
involvement of mitochondrial alteration and reactive oxygen species generation in taiwan cobra cardiotoxin-induced apoptotic death of human neuroblastoma sk-n-sh cells.naja naja atra cardiotoxin 3 (ctx3) induced apoptotic death on human neuroblastoma sk-n-sh cells. the apoptosis signals of ctx3 included reactive oxygen species (ros) generation, disruption of mitochondrial membrane potential (deltapsim), cytochrome c release to the cytosol and activation of caspase-9 and -3. however, ctx3-induced increase in mitochondrial permeability transition was not initiated by proteins of the bcl-2 family. the collapse of deltapsim, release of cytosolic cytochrome c, prod ...200818619991
increase of the cytotoxic effect of bothrops jararacussu venom on mouse extensor digitorum longus and soleus by potassium channel blockers and by na(+)/k(+)-atpase inhibition.we investigated the myotoxicity of bothrops jararacussu crude venom and other cytolytic agents on mouse isolated extensor digitorum longus (edl) and soleus (sol) muscles, which present distinct properties: edl is a fast-twitch, white muscle with predominantly glycolytic fibers, while sol is slow-twitch, red muscle with predominantly oxidative fibers. muscles were exposed to b. jararacussu crude venom (25 microg/ml) and other crotaline venoms (agkistrodon contortrix laticinctus; crotalus viridis ...200818675839
inn-toxin, a highly lethal peptide from the venom of indian cobra (naja naja) venom-isolation, characterization and pharmacological actions.a novel toxic polypeptide, inn-toxin, is purified from the venom of naja naja using combination of gel-permeation and ion-exchange chromatography. it has a molecular mass of 6951.6da as determined by maldi-tof/ms and the n-terminal sequence of lkxnklvplf. it showed both neurotoxic as well as cytotoxic activities. inn-toxin is lethal to mice with a ld(50) of 1.2mg/kg body weight. igy raised in chicks against basic peptide pool neutralized the toxicity of inn-toxin. inn-toxin did not inhibit choli ...200818760317
cardiotoxin iii induces c-jun n-terminal kinase-dependent apoptosis in hl-60 human leukaemia cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. the molecular effects of ctx iii on hl-60 cells were dissected in the present study. we found that the antiproliferative action of ctx iii on hl-60 cells was mediated through apoptosis, as characterized by an increase of sub g1 population, dna fragmentation and poly(adp-ribose) polymerase (parp) cleavage. upregulation of bax, downregulation ...200817514639
purification and characterization of a novel antinociceptive toxin from cobra venom (naja naja atra).snake venoms have demonstrated antinociceptive activity, and certain isolated neurotoxins have demonstrated significant analgesia in animal models. here we report a novel analgesic toxin which was isolated from naja naja atra and was given the name 'najanalgesin'. the ld(50) of the crude venom and najanalgesin were 0.89mg/kg and 2.69mg/kg, respectively. we used the writhing test and hot plate test to evaluate the antinociceptive properties of the crude venom and najanalgesin after intraperitonea ...200818765245
isolation, purification, crystallization and preliminary crystallographic studies of sagitoxin, an oligomeric cardiotoxin from the venom of naja naja saggitifera.sagitoxin, a novel cardiotoxin from the venom of naja naja saggitifera, has been successfully isolated, purified to homogeneity and crystallized. the toxin was purified using successive separation steps on a cm-sephadex c-50 column and a reverse-phase column. the 6.75 kda toxin was sequenced by the edman method using a ppsq-21 protein sequencer. it was crystallized using the hanging-drop vapour-diffusion method. the hexagonal-shaped crystals diffracted to 3.0 a resolution and belonged to space g ...200818540072
interaction of group ia phospholipase a2 with metal ions and phospholipid vesicles probed with deuterium exchange mass spectrometry.deuterium exchange mass spectrometric evaluation of the cobra venom (naja naja naja) group ia phospholipase a 2 (gia pla 2) was carried out in the presence of metal ions ca (2+) and ba (2+) and phospholipid vesicles. novel conditions for digesting highly disulfide bonded proteins and a methodology for studying protein-lipid interactions using deuterium exchange have been developed. the enzyme exhibits unexpectedly slow rates of exchange in the two large alpha-helices of residues 43-53 and 89-101 ...200818500818
antioxidants: promising neuroprotection against cardiotoxin-4b-induced cell death which triggers oxidative stress with early calpain activation.cardiotoxin-4b (ctx-4b), isolated from naja naja sputatrix venom, shows lethality in several cell types. employing murine primary cortical neurons, this study was undertaken to investigate the molecular mechanisms of ctx-4b in the induction of neuronal death. ctx-4b induced a dose- and time-dependent neuronal death. strong induction of calpains as early as 4h post-ctx-4b 75 nm treatment was detected in neurons with negligible caspase 3 activation. for the first time in cultured murine primary co ...200818377942
mapping the functional topography of a receptor.photoactivatable derivatives of the alpha-neurotoxin ii from naja naja oxiana are useful tools for investigating the three dimensional architecture of the extra-membrane part of the nicotinic acetylcholine receptor from the electric tissue of torpedo californica. three derivatives, carrying an azidobenzoyl group in position lys-15, lys-26, and lys-46, respectively, are shown to react differently within the receptor's quaternary structure. especially the lys-26 and lys-46 derivatives can be used ...20071299215
the mechanism of cytotoxicity by naja naja atra cardiotoxin 3 is physically distant from its membrane-damaging effect.in order to dissect out whether multiple activities of cardiotoxins (ctxs) are connected, to some extent, with each other, studies on reduced and s-carboxyamidomethylated (rcam) naja naja atra ctx3 were carried out in the present study. although both ctx3 and rcam-ctx3 induced apoptotic death of pc-3 cells as evidenced by propodium iodide/annexin v double staining, degradation of procaspases and dna fragmentation, the cytotoxicity of rcam-ctx3 was mostly 100-fold lower than that noted with nativ ...200717714752
actions of snake neurotoxins on an insect nicotinic cholinergic synapse.here we examine the actions of six snake neurotoxins (alpha-cobratoxin from naja naja siamensis, erabutoxin-a and b from laticauda semifasciata; cm12 from n. haje annulifera, toxin iii 4 from notechis scutatus and a long toxin from n. haje) on nicotinic acetylcholine receptors in the cercal afferent, giant interneuron 2 synapse of the cockroach, periplaneta americana. all toxins tested reduced responses to directly-applied ach as well as epsps evoked by electrical stimulation of nerve xi with si ...200717710455
[effect of ngf, which is isolated and purified from the venom of naja naja atra, on expression of gap-43 in dorsal root ganglia removed partially from cat].to investigate the effect of the nerve growth factor (ngf), which is isolated and purified from the venom of naja naja atra, on expression of gap-43 in dorsal root ganglia (drg) removed partially from cat.200717593821
effects of cardiotoxin iii on expression of genes and proteins related to g2/m arrest and apoptosis in k562 cells.cardiotoxin iii (ctx iii) is a basic polypeptide of 60-amino acid residues isolated from naja naja atra venom, exerts its anti-proliferative activity in human leukemia k562 cells. in the present study, the expression of mrnas and proteins related to cell cycle and apoptosis in human leukemia k562 cells induced by ctx iii was investigated by semi-quantitative reverse transcription-polymerase chain reaction (rt-pcr) and western blot analysis. flow cytometric analysis revealed that ctx iii resulted ...200717149543
region-specific neutralization of indian cobra (naja naja) venom by polyclonal antibody raised against the eastern regional venom: a comparative study of the venoms from three different geographical distributions.indian cobra (naja naja) venoms from different geographical locations vary in their composition, biochemical, and pharmacological properties. venom samples from eastern, western and southern india are compared in this study. the venom from eastern region was found to be the most lethal of the three regional venoms. monovalent antivenom (nnev-igg) prepared against the eastern venom was found to cross-react with the other two regional venoms. nnev-igg at an ag:ab ratio of 1:25 completely neutraliz ...200717161818
purification, partial characterization, crystallization and preliminary x-ray diffraction of a novel cardiotoxin-like basic protein from naja naja atra (south anhui) venom.a novel cardiotoxin-like basic protein was isolated from the venom of the chinese cobra (naja naja atra) from the south of anhui in china. the protein inhibits the expression of vascular endothelial growth factor and basic fibroblast growth factor in human lung cancer cell line h1299 and induces the haemolysis of rabbit erythrocytes under low-lecithin conditions. after a two-step chromatographic purification, the resultant 7 kda protein was crystallized by the hanging-drop vapour-diffusion metho ...200717277458
involvement of c-jun n-terminal kinase in g2/m arrest and caspase-mediated apoptosis induced by cardiotoxin iii (naja naja atra) in k562 leukemia cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, may have a potentiality as a structural template for rational drug design in killing cancer cells. treatment of k562 cells with 0.3 microm of ctx iii resulted in g2/m phase cell cycle arrest that was associated with a marked decline in protein levels of g2/m regulatory proteins including cyclin a, cyclin b1, cdk2 and cdc25c. in contrast to no effect on the phosphorylation of erk, p38 ma ...200717368702
snakes of medical importance in india: is the concept of the "big 4" still relevant and useful?snakebites continue to be a major medical concern in india. however, there is very little hard evidence of a numerical nature to enable us to understand which species are responsible for mortality and morbidity. for many decades, the concept of the "big 4" snakes of medical importance has reflected the view that 4 species are responsible for indian snakebite mortality--the indian cobra (naja naja), the common krait (bungarus caeruleus), the russell's viper (daboia russelii) and the saw-scaled vi ...200717447706
protective action of snake venom naja naja oxiana at spinal cord hemisection.based on data accumulated regarding the neuroprotective action of proline-rich-peptide-1 (prp-1, a fragment of neurophysin vasopressin associated hypothalamic glycoprotein consisting of 15 amino acid residues) on neurons survival and axons regeneration and taking into the account that lvv-hemorphin-7 (lvv-h7, an opioid peptide, widely distributed in different cell types of various tissues of intact rats, including those of the nervous and immune systems) derived from the proteolytic processing o ...200717451057
group iia secretory pla2 inhibition by ursolic acid: a potent anti-inflammatory molecule.ursolic acid (3beta-hydroxy-urs-12-en-28-oic acid) isolated from many medicinal plants has diverse pharmacologically important properties, including strong anti-inflammatory activity. however its interaction with pro-inflammatory pla2 is not known. ursolic acid inhibited secretory pla2 (spla2) enzymes purified from vipera russelli, naja naja venom and human pleural fluid and synovial fluid. ic50 values determined for these enzymes ranged from 12 to 18 microm. group ii secretory pla2 from both ve ...200717456043
purification, sequencing and structural characterization of the phospholipase a1 from the venom of the social wasp polybia paulista (hymenoptera, vespidae).the biochemical and functional characterization of wasp venom toxins is an important prerequisite for the development of new tools both for the therapy of the toxic reactions due to envenomation caused by multiple stinging accidents and also for the diagnosis and therapy of allergic reactions caused by this type of venom. pla(1) was purified from the venom of the neotropical social wasp polybia paulista by using molecular exclusion and cation exchange chromatographies; its amino acid sequence wa ...200717761205
investigation of ligand-binding sites of the acetylcholine receptor using photoactivatable derivatives of neurotoxin ii from naja naja oxiana.several photoaffinity derivatives of neurotoxin ii from the venom of the central asian cobra naja naja oxiana have been prepared. after reaction of the 125i-labeled derivatives with the nicotinic acetylcholine receptor from electric organ, the alpha-subunit of the nachr is almost exclusively labeled by the derivative carrying the photoactivatable group in position lys46. in contrast to this, a reactive group at lys26 predominantly labels the gamma- and delta-subunits, while the alpha- and beta-s ...20061525162
a glycoprotein from a folk medicinal plant, withania somnifera, inhibits hyaluronidase activity of snake venoms.venom hyaluronidases help in rapid spreading of the toxins by destroying the integrity of the extra-cellular matrix of the tissues in the victims. a hyaluronidase inhibitor (wsg) is purified from a folk medicinal plant, withania somnifera. the glycoprotein inhibited the hyaluronidase activity of cobra (naja naja) and viper (daboia russelii) venoms, which was demonstrated by zymogram assay and staining of the skin tissues for differential activity. wsg completely inhibited the activity of the enz ...200616513428
inhibition of naja naja venom hyaluronidase: role in the management of poisonous bite.hyaluronidase is present virtually in all snake venoms and has been known as a "spreading factor." the enzyme damages the extracellular matrix at the site of the bite, leading to severe morbidity. in this study, the benefits of inhibiting the hyaluronidase activity of indian cobra (naja naja) venom have been investigated. anti-nnh1 and aristolochic acid both inhibited the in vitro activity of the purified hyaluronidase, (nnh1) and the hyaluronidase activity of whole venom in a dose-dependent man ...200616253285
strong myotoxic activity of trimeresurus malabaricus venom: role of metalloproteases.trimeresurus malabaricus is an endemic snake found in the southern region of western ghats section of india along with the more widely distributed species like naja naja and daboia russelii. t. malabaricus venom is not lethal when injected (i.p.) up to 20 mg/kg body weight in mice, but causes extensive local tissue degeneration. n. naja and d. russelii are highly toxic (i.p.) with minimum local tissue damage in experimental mice. in this study a comparative analysis of local tissue damage of t. ...200616317522
north american coral snake antivenin for the neutralization of non-native elapid venoms in a murine model.north american coral snake antivenin (csav; wyeth antivenin [micrurus fulvius], equine origin) is approved for the treatment of coral snake envenomations in the united states. the coral snake is the only elapid that is native to north america, but envenomations from non-native elapids are occurring more commonly in this country. this study was designed to evaluate the efficacy of csav in the neutralization of two exotic elapid envenomations: naja naja (indian cobra) and dendroaspis polylepsis (b ...200616436788
mechanisms of cardiotoxin lll-induced apoptosis in human colorectal cancer colo205 cells.cardiotoxin iii (ctx iii) is a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom. this is the first report on the mechanism of the anticancer effect of ctx iii in human colorectal cancer colo205 cells. 2. cardiotoxin iii-induced colo205 cell apoptosis was confirmed by dna fragmentation (dna ladder and sub-g1 formation) with an ic(50) of 4 mg/ml at 48 h. 3. further mechanistic analysis demonstrate that ctx iii induced the loss of mitochondrial membrane potential (dy ...200616487259
purification of a post-synaptic neurotoxic phospholipase a2 from naja naja venom and its inhibition by a glycoprotein from withania somnifera.a post-synaptic neurotoxic phospholipase a(2) (pla(2)) has been purified from indian cobra naja naja venom. it was associated with a peptide in the venom. the association was disrupted using 8 m urea. it is denoted to be a basic protein by its behavior on both ion exchange chromatography and electrophoresis. it is toxic to mice, ld(50) 1.9 mg/kg body weight (ip). it is proved to be post-synaptic pla(2) by chymographic experiment using frog nerve-muscle preparation. a glycoprotein, (wsg) was isol ...200616494989
a neurotoxic phospholipase a2 variant: isolation and characterization from eastern regional indian cobra (naja naja) venom.cm-sephadex c-25 column chromatography profile of indian cobra (naja naja) venom from eastern region showed a distinct and a dominant phospholipase peak, peak-10, while it was not seen in either southern or western venom samples. peak-10 was subjected to cm-sephadex c-25 and sephadex g-50 column chromatography to isolate nn-x-pla(2). nn-x-pla(2) is a single chain protein with the relative molecular weight of 10kda by sds-page. it was toxic to mice with an ld(50) value 0.098 mg/kg body weight (i. ...200616574178
differential action of proteases from trimeresurus malabaricus, naja naja and daboia russellii venoms on hemostasis.the action of venom proteases and their role in hemostasis has been compared in the venoms of trimeresurus malabaricus, daboia russellii and naja naja from the southern region of western ghats, india. these venoms exhibit varying amounts of proteolytic activity and also influence hemostasis differently. casein hydrolyzing activity of t. malabaricus venoms was 16 and 24 fold higher than those of n. naja and d. russellii venoms, respectively. with the synthetic substrate tame, the highest activity ...200616627005
mutagenesis studies on the n-terminus and thr54 of naja naja atra (taiwan cobra) chymotrypsin inhibitor.ala-screening mutagenesis studies on arg1, pro2, arg3, phe4 and thr54 of naja naja atra (taiwan cobra) chymotrypsin inhibitor showed that inhibitory potency and gross conformation of the mutants were not significantly different from those of wild-type inhibitor. nevertheless, the r1a mutant had an appreciable decrease in the structural stability underlying thermal unfolding and urea-induced denaturation. alternatively, deleting the first three residues at the n-terminus caused a reduction in str ...200616703468
use of egg yolk antibody (igy) as an immunoanalytical tool in the detection of indian cobra (naja naja naja) venom in biological samples of forensic origin.an immunoglobulin y (igy) based indirect double antibody sandwich enzyme linked immunosorbent assay (elisa) was developed for the detection of indian cobra (naja naja naja) venom in the biological samples of forensic origin. polyclonal antibodies were raised and purified from chick egg yolk and rabbit serum. the cobra venom was sandwiched between immobilized affinity purified igy and the rabbit igg. the detection concentration of cobra venom was in the range of 0.1 to 300ng. the calibration plot ...200616846624
modification of lys-6 and lys-65 affects the structural stability of taiwan cobra phospholipase a2.to assess whether chemical modification of phospholipase a(2) (pla(2)) enzymes may affect their fine structure and consequently alter their enzymatic activity, the present study was carried out. both lys-6 and lys-65 in the taiwan cobra (naja naja atra) pla(2) were selectively modified with trinitrobenzene sulfonate and pyridoxal-5'-phosphate (plp), respectively. incorporation of either trinitrophenylated (tnp) or plp groups on lys-6 and lys-65 caused a drop in pla(2) activity, but the ca(2+)-bi ...200616862455
up-regulation of bax and endonuclease g, and down-modulation of bcl-xl involved in cardiotoxin iii-induced apoptosis in k562 cells.cardiotoxin iii (ctx iii), a basic polypeptide with 60 amino acid residues isolated from naja naja atra venom, has been reported to have anticancer activity. ctx iii-induced k562 cell apoptosis was confirmed by dna fragmentation (dna ladder, sub-g1 formation) and phosphatidylserine (ps) externalization with an ic(50) value of 1.7 microg/ml at 48 h. a mechanistic analysis demonstrated that ctx iii-induced apoptotic cell death was accompanied by up-regulation of both bax and endonuclease g (endo g ...200616953123
alpha-lipoic acid: an inhibitor of secretory phospholipase a2 with anti-inflammatory activity.alpha-lipoic acid (ala) and its reduced form dihydrolipoic acid (dhla) are powerful antioxidants both in hydrophilic and lipophylic environments with diverse pharmacological properties including anti-inflammatory activity. the mechanism of anti-inflammatory activity of ala and dhala is not known. the present study describes the interaction of ala and dhala with pro-inflammatory secretory pla(2) enzymes from inflammatory fluids and snake venoms. in vitro enzymatic inhibition of spla(2) from viper ...200617011589
a short-chain alpha-neurotoxin from naja naja atra produces potent cholinergic-dependent analgesia.objective to investigate the analgesia induced by cobrotoxin (ct) from venom of naja naja atra, and the effects of atropine and naloxone on the antinociceptive activity of ct in rodent pain models. methods ct was administered intraperitoneally (33.3, 50, 75 mu g/kg), intra-cerebral venticularly (2.4 mu g/kg) or microinjected into periaqueductal gray (pag, 1.2 mu g/kg). the antinociceptive action was tested using the hot-plate test and the acetic acid writhing test in mice and rats. the involveme ...200617687406
structural and functional analysis of natrin, a venom protein that targets various ion channels.cysteine-rich secretory proteins (crisps) are secreted single-chain proteins found in different sources. natrin is a member of the crisp family purified from the snake venom of naja naja atra, which has been reported as a bkca channel blocker. in our study, crystals of natrin were obtained in two different crystal forms and the structure of one of them was solved at a resolution of 1.68a. our electrophysiological experiments indicated that natrin can block the ion channel currents of the voltage ...200617070778
purification and characterization of ophiophagus hannah cytotoxin-like proteins.three cytotoxin-like proteins from the venom of ophiophagus hannah were isolated by a combination of ion exchange chromatography and reverse phase hplc. amino acid sequence analysis revealed that these proteins all consisted of 63 amino acids and shared approximate 50% and 56% sequence identity with naja naja atra cardiotoxins and cardiotoxin-like basic proteins (clbps), respectively. cd spectra revealed that their secondary structure was dominated with beta-sheet as those noted with cardiotoxin ...200616899267
optically trapping confocal raman microscopy of individual lipid vesicles: kinetics of phospholipase a(2)-catalyzed hydrolysis of phospholipids in the membrane bilayer.phospholipase a2 (pla2)-catalyzed hydrolysis at the sn-2 position of 1,2-dimyristoyl-sn-glycero-3-phosphocholine in optically trapped liposomes is monitored in situ using confocal raman microscopy. individual optically trapped liposomes (0.6 microm in diameter) are exposed to pla2 isolated from cobra (naja naja naja) venom at varying enzyme concentrations. the relative raman scattering intensities of c-c stretching vibrations from the trans and gauche conformers of the acyl chains are correlated ...200617007516
anticoagulant effect of naja naja venom 5'nucleotidase: demonstration through the use of novel specific inhibitor, vanillic acid.the snake venom proteins affect hemostasis by either advancing/delaying blood coagulation. apart from proteases and phospholipase a(2)s (pla(2)s), 5'nucleotidase is known to affect hemostasis by inhibiting platelet aggregation. in this study, the possible involvement of naja naja venom 5'nucleotidase in mediating anticoagulant affect is evaluated. vanillic acid selectively and specifically inhibited 5'nucleotidase activity among other enzymes present in n. naja venom. it is a competitive inhibit ...200616899266
crystal structure of a heterodimer of phospholipase a2 from naja naja sagittifera at 2.3 a resolution reveals the presence of a new pla2-like protein with a novel cys 32-cys 49 disulphide bridge with a bound sugar at the substrate-binding site.the crystal structure of the phospholipase a2 (pla2) heterodimer from naja naja sagittifera reveals the presence of a new pla2-like protein with eight disulphide bridges. the heterodimer is formed between a commonly observed group i pla2 having seven characteristic disulfide bonds and a novel pla2-like protein (cys-pla2) containing two extra cysteines at two highly conserved sites (positions 32 and 49) of structural and functional importance. the crystals of the heterodimer belong to tetragonal ...200616287060
crystal structure of a novel phospholipase a2 from naja naja sagittifera with a strong anticoagulant activity.this is the first pla(2) crystal structure from group i that shows a strong anticoagulant property. the monomeric pla(2) was purified from the venom of naja naja sagittifera (indian cobra). its amino acid sequence has been determined using cdna technique. the amino acid sequence of spla(2) contains three positively charged and two negatively charged residues in the segment 54-71 (numbering scheme of spla(2)) thus giving this region an overall cationic amphiphilic surface. this suggested the pres ...200516269164
[poisonous animals registration in poland].the act on nature conservation of 16.04.2004 (official journal, 2004, no 92, item 880) imposes on private individuals the duty to register some animals. the data collected by kraków municipal authorities and delivered to the poison information centre (colleglum medicum, jagiellonian university) indicate that there are following species in private hands in the city and its surroundings: 11 individuals of naja naja, 2--hydrodynates gigas and 55-- dendrobates spp. according to these information the ...200516225138
inhibition of naja naja venom hyaluronidase by plant-derived bioactive components and polysaccharides.the inhibitory effect of several bioactive compounds on the activity of hyaluronidase enzyme purified from naja naja venom was investigated in vitro. compounds were found to inhibit the hyaluronidase activity dose dependently. among glycosaminoglycans, heparin, heparan sulfate, and dermatan sulfate showed maximum inhibition compared to chondroitin sulfates. different molecular forms of chitosan inhibit the enzyme, and inhibition appears to depend on the chain length. in addition, plant-derived b ...200516212553
crystal structure of a novel phospholipase a2 from crude venom of indian cobra sub-species naja naja sagittifera at 1.48 angstoms resolution.secretory phospholipase a2s (pla2s), the structurally-homologous enzymes share a common qualitative catalytic site, but differ greatly in their pharmacological properties and toxicities. there has been a recognizable pattern of mutations in the primary sequence of pla2s that alter their catalytic properties significantly. in the present study, the amino acid sequence and the three-dimensional structure of a new isoform of pla2 from crude venom of indian cobra sub-species naja naja sagittifera (n ...200523923535
structure of the zinc-induced heterodimer of two calcium-free isoforms of phospholipase a2 from naja naja sagittifera at 2.7 angstroms resolution.the crystal structure of a zinc-induced heterodimer of two metal-free isoforms of a cobra venom phospholipase a(2) has been determined at 2.7 angstroms resolution. the crystals belong to space group p4(1), with unit-cell parameters a = b = 65.5, c = 58.4 angstroms, and have a single dimer in the asymmetric unit. the structure has been refined to r(cryst) and r(free) factors of 0.188 and 0.232, respectively. the two isoforms have a sequence identity of 82%. the zinc ion forms a fivefold coordinat ...200515735340
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