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Consequences of Mesobuthus tamulus gangeticus (Pocock, 1900) envenomation in albino mice
Chaubey, MK;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2010, DOI: 10.1590/S1678-91992010000300011
Abstract: the present study aimed to investigate the effects of mesobuthus tamulus gangeticus pocock (buthidae) venom on albino mice (nih strain). whole venom was obtained by electrical stimulation and its toxicity was determined in albino mice by subcutaneous envenomation. the venom ld50 was 2.5 mg kg-1 of mouse body weight. toxic effects on different biochemical and enzymatic parameters in blood serum and other tissues of albino mice were determined after experimental envenomation with sublethal doses of m. tamulus gangeticus venom. increased levels of glucose, uric acid and cholesterol, as well as decreased serum total proteins, were observed at 2 and 4 hours after the envenomation. in the liver and muscles, glycogen content dropped after venom injection. moreover, m. tamulus gangeticus venom elevated the enzymatic activity of acid phosphatase (acp), lactic dehydrogenase (ldh) and alanine aminotransferase (alt) in the serum of albino mice. in conclusion, m. tamulus gangeticus can be considered a lethal scorpion species.
The action of red scorpion (Mesobuthus tamulus coconsis, pocock) venom and its isolated protein fractions on blood sodium levels
Badhe, R. V.;Thomas, A. B.;Deshpande, A. D.;Salvi, N.;Waghmare, A.;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2007, DOI: 10.1590/S1678-91992007000100006
Abstract: red scorpion (mesobuthus tamulus or buthus tamulus) venom samples were collected at different regions of india: western (chiplun and ahmednagar from maharashtra state) and southern (ratnagiri and chennai from tamil nadu state). the action of whole venoms on the blood sodium levels of mice was assessed using flame photometry. seven peptides were common to all venom samples. they were separated using the native polyacrylamide gel electrophoresis (page) technique and their activities were also studied using flame photometry. there was a decrease in the concentration of sodium ions in the serum, which suggested the blockage of such ions by scorpion venom toxins. among the 10 protein bands isolated, the band at 79.6 kda presented maximum activity in decreasing serum sodium ions concentration. whole venom from chiplun region also showed maximum activity. the western blotting technique demonstrated that the anti-scorpion venom sera produced by haffkine biopharmaceuticals corporation ltd., india, neutralized all four venom samples.
Journal of Venomous Animals and Toxins , 1999, DOI: 10.1590/S0104-79301999000100004
Abstract: severe envenoming was induced in two groups of experimental dogs after subcutaneous (sq) injection of venom of the scorpion (mesobuthus tamulus concanesis, pocock) (3.0 and 3.5 mg/kg body weight). the circulating levels of blood sugar, insulin, glucagon, and cortisol were assayed at 0, and 30, 60, 90 and 120 min after venom injection. there was an increase in the circulating levels of blood sugar, insulin, glucagon, and cortisol following envenoming. scorpion envenoming causes an autonomic storm resulting in a massive release of catecholamines, angiotensin ii, glucagon, and cortisol accompanied by changes in insulin secretion. the rise in the counter-regulatory hormones (glucagon, cortisol, and catecholamines) oppose the anabolic actions of insulin resulting in a variety of clinical manifestations. these changes may lead to a syndrome of fuel-energy deficits and to an inability of the vital organs to utilise the existing metabolic substrates, ultimately resulting in multisystem organ failure (msof) and death.
Group III PLA2 from the scorpion, Mesobuthus tamulus: cloning and recombinant expression in E. coli
Hariprasad,Gururao; Saravanan,Kolandaivelu; Singh,Sundararajan Baskar; Das,Utpal; Sharma,Sujata; Kaur,Punit; Singh,Tej Pal; Srinivasan,Alagiri;
Electronic Journal of Biotechnology , 2009,
Abstract: phospholipases a2 (pla2) are enzymes that specifically hydrolyze the sn-2 fatty acid acyl bond of phospholipids, producing a free fatty acid and a lyso-phospholipid. we report the cloning and expression of a secretory phospholipase a2 (spla2) from mesobuthus tamulus, indian red scorpion. the nucleotide sequence codes for a 167 residue enzyme. the open reading frame codes for a 31 amino acid signal peptide followed by a mature portion of the protein. the primary structure shows the calcium binding motif, catalytic residues, 8 highly-conserved cysteines and c-terminal extension which classify it as a group iii pla2. the entire transcript was expressed in escherichia coli and was purified by metal affinity chromatography under denaturing conditions. the protein was refolded by serial dilutions in the refolding buffer to its active form. hemolytic assays indicate that the protein adopts a functional conformation. the functional requisites such as optimum ph of 8 and calcium dependency are shown. this report provides a simple but robust methodology for recombinant expression of toxic proteins.
Journal of Venomous Animals and Toxins , 1999, DOI: 10.1590/S0104-79301999000200004
Abstract: acute myocardiopathy in experimental dogs and rabbits was induced by subcutaneous (sq) injection of 3.5 mg/kg of scorpion venom from mesobuthus tamulus concanesis, pocock. an increase in circulating lactic dehydrogenase (ldh), serum glutamic oxalacetic transaminase (sgot), creatine kinase-mb isoenzyme (ck-mb), serum glutamine pyrovate transaminase (sgpt) and alpha hydroxy butyrate dehydrogenase (hbdh) enzyme levels was observed in dogs 60 min after venom injection, and a further rise was observed 120 min after venom injection. the administration of the species-specific scorpion antivenom (sav) at different time intervals after venom injection resulted in reversal of electrocardiographic changes and a reduction in cardiac enzyme levels. the administration of sav to scorpion envenomed alloxan-pretreated animals did not cause clinical or biochemical improvement. on the other hand, administering insulin to envenomed only animals or envenomed alloxan-pretreated animals resulted in a biochemical and clinical improvement, as well as in a reduction of the cardiac enzyme levels. insulin administration in scorpion envenoming syndrome is essentially a metabolic support to control the adverse effects triggered by catecholamines and other counter-regulatory hormones.
Intraspecific variation in protein pattern of red scorpion (Mesobuthus tamulus, coconsis, pocock) venoms from Western and Southern India
Badhe, R. V.;Thomas, A. B.;Harer, S. L.;Deshpande, A. D.;Salvi, N.;Waghmare, A.;
Journal of Venomous Animals and Toxins including Tropical Diseases , 2006, DOI: 10.1590/S1678-91992006000400008
Abstract: red scorpions mesobuthus tamulus (coconsis, pocock) were obtained from different regions of west and south india (ratnagiri, chiplun and ahmednagar from maharashtra and chennai from tamil nadu, respectively). their venoms composition was analyzed using gel electrophoresis (sds-page). all venom samples shared six bands of 170, 80, 60, 57, 43, and 38 kda molecular weights. bands of 115 kda and 51.5 kda were characteristic of venoms obtained from red scorpions of chiplun region, and the 26kda band was absent in scorpion venom from tamil nadu. the separated protein band patterns suggest that the venoms from ratnagiri, ahmednagar and tamil nadu had high similarities in their biochemical composition but differed from that of chiplun region. these data were also supported by the jaccard (j) index. the j value was 0.33 for venom obtained from ratnagiri-ahmednagar, 0.31 for venom from ratnagiri-tamil nadu, and 0.3 for venom from ratnagiri-chiplun region. this suggests the existence of genetic variation among the different strains of red scorpion in western and southern india. the antiserum produced by haffkine biopharmaceuticals corporation ltd. completely neutralized proteins of venoms from all the regions studied.
Journal of Venomous Animals and Toxins , 2002, DOI: 10.1590/S0104-79302002000100004
Abstract: electrocardiographic (ecg) changes were induced in dogs by injection of scorpion venom from mesobuthus tamulus concanesis, pocock. venom (3 mg/kg body weight) was given subcutaneously (sq) while 10 ml of scorpion antivenom (sav) was administered intravenously (iv) to experimental dogs. group 1 received only the venom; groups 2, 3, and 4 received sav at 0, 30, and 60 min, respectively, following envenoming. thick, ropy and profuse salivation; muscle fasciculation; clonus and tetany-like contractions; frequent urination; and bowel emptying sometimes stained with bile and occasionally blood and bile were observed 20-25 minutes after envenoming. following envenoming, hyperglycemia, increase in free fatty acid (ffa) levels, and reduction in triglyceride levels were observed in groups 1, 3, and 4. there was an initial rise in insulin levels at 30 min followed by a reduction at 60 min. sav caused a subsequent rise in insulin levels but there was a reduction in blood sugar to euglycemia levels and lipogenesis (reduction in ffa and increase in triglycerides levels) in groups 3 and 4. abnormal ecg changes and arrhythmias were not observed after sav. normal sinus rhythm was restored in group 4. scorpion envenoming with multi-system-organ failure (msof), characterized by a massive release of counter-regulatory hormones (catecholamines, glucagon, cortisol), angiotensin-ii, and changes in insulin secretion, is a condition of fuel-energy deficits and an inability to utilize the existing metabolic substrates. these disturbances are reversed by sav possibly through insulin release. it is concluded that sav, under the laboratory conditions, effectively neutralizes, prevents, and reverses scorpion venom toxicity.
Isolation of 5-Hydroxytryptamine from the Venom of the Indian Red Scorpion (Mesobuthus tamulus)
Mesobuthus tamulusA.K. Tiwari, M.B. Mandal, S. Kanoo, A.B. Alex, A.C. Jariwala and S.B. DeshpandeMBTMBTMBT
The Open Toxinology Journal , 2008, DOI: 10.2174/1875414700801010001]
Abstract: The present study was undertaken to isolate 5-hydroxytryptamine (5-HT) from crude Indian red scorpion (Mesobuthus tamulus; MBT) venom as it has not been reported yet. Therefore, with the help of bioassay (using gastric fundus contractions) and fluorimetric assay methods, the 5-HT content of crude MBT venom (CV) was determined. The concentration of 5-HT in CV by either of the methods was different (117 times). Further, a 5-HT antagonist methysergide partially blocked the CV-induced gastric fundus contractions. Hence, for isolation and determination of 5-HT in crude MBT venom, CV was subjected to Sephadex gel (G 75-125) filtration chromatography. The eluates were screened for optical density (OD) at 280 nm, lethality and gastric fundus contractions. Two peaks of enhanced gastric fundus contractions were observed between 26-70 ml and 90 -110 ml of eluate volumes. As the first peak (between 26-70 ml) eluates exhibited high OD and lethality, further analysis was not undertaken. The second peak (between 90-110 ml) eluates exhibited very low OD and were non-lethal. On bioassay, the 5-HT content of pooled eluates of second peak was 0.0398 ± 0.008 μg/ml and by fluorimetric assay it was 0.0396 ± 0.007 μg/ml. The 5-HT concentration of crude MBT venom per unit mass was 0.0175 ± 0.0035 μg/mg by bioassay and 0.0174 ± 0.0031 μg/mg by fluorimetric assay. Further, the gastric fundus contractions elicited by second peak eluates were blocked by methysergide (1.0 μM). Thus, the second peak eluates of crude MBT venom contain 5-HT and its concentration was about 0.0174 μ/mg.
Role of serotonergic mechanism in gastric contractions induced by Indian red scorpion (Mesobuthus tamulus) venom  [cached]
Tiwari A,Mandal M,Deshpande S
Indian Journal of Pharmacology , 2009,
Abstract: Aim : Gastric dysfunctions are commonly seen after scorpion envenomation, and the underlying mechanisms are not clear. Therefore, the present study was undertaken to investigate the effect of Indian red scorpion (Mesobuthus tamulus, MBT) venom on gastric fundus muscle contraction and the underlying mechanisms involved. Materials and Methods : In vitro isometric contraction was recorded from gastric fundus muscle strips on a chart recorder. The tissue was exposed to different concentrations of serotonin or crude MBT venom. The contractile responses to venom were expressed as the percentage of maximum contraction produced by serotonin at the beginning of each experiment. The contractile responses to 1.0 μg/ml of crude MBT venom were ascertained in the absence or presence of serotonin antagonist, methysergide. Results : Serotonin produced concentration-dependent fundus contractions (0.004-4.0 μM), and maximum contractile response was observed at 4.0 μM of serotonin. Hence, the contractile response obtained at 4.0 μM of serotonin was taken for normalization. The crude MBT venom (0.1-1.0 μg/ml) produced a concentration-dependent increase in fundus contractions (as % of maximum fundus contraction produced by serotonin at 4.0 μM). The maximum response was observed at 1.0 μg/ml of crude venom and a further increase in the concentration, up to 3.0 μg/ml, did not increase the response. In a separate series of experiments, pre-treatment with methysergide (1.0 μM) significantly attenuated the contractile response elicited by the venom (1.0 μg/ml) (P< 0.05) and blocked the serotonin (4.0 μM) response. Conclusion : The results suggest that the crude MBT venom produces gastric fundus contractions by partially involving serotonin.
The use of antivenom reverses hematological and osmotic fragility changes of erythrocytes caused by indian red scorpion Mesobuthus tamulus concanesis POCOCK in experimental envenoming
Journal of Venomous Animals and Toxins , 2001, DOI: 10.1590/S0104-79302001000100008
Abstract: acute myocarditis was induced in experimental dogs by subcutaneous (sc) injection of 3mg/kg of scorpion venom from mesobuthus tamulus concanesis pocock (earlier called buthus tamulus). an increase in hemoglobin (hb), mean corpuscular hemoglobin concentration (mchc), packed cell volume (pcv), plasma hemoglobin (plasma hb) levels, and increased osmotic fragility of erythrocytes in vivo was observed after envenoming. an increase in osmotic fragility of red blood cells (rbc) was also observed when the blood in vitro was incubated with different concentrations of scorpion venom. species- specific scorpion antivenom (sav) was administered to different groups of animals at different time intervals following scorpion envenoming. this resulted in a decrease in hb, mchc, pcv, and plasma hb levels in the envenomed animals and reversal of osmotic fragility changes of erythrocytes. it has been suggested that scorpion venom causes an autonomic storm releasing massive amounts of counter-regulatory hormones, such as catecholamines, angiotensin-ii, glucagon, cortisol, and changes in insulin secretion resulting in hematological and osmotic fragility changes of erythrocytes. administration of sav effectively neutralized, prevented, and reversed scorpion venom toxicity and related osmotic fragility changes of erythrocytes.
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