Alternatus Venom Research Articles

Potential low-impact immunogen for the production of anti-bothropic serum: Bothrops alternatus venom treated with Na2EDTA

This study proposes an alternative method using Na2EDTA to neutralize B. alternatus venom and using it as an immunogen from the start of inoculation to minimize side effects and enhance antivenom production. To achieve this, 1.8 mg/mL of B. alternatus venom (B.aV) was treated with Na2EDTA, and any extra chelate was eliminated by filtering the resulting solution through a Sephadex G-25 column. Two groups of BALB/c mice were immunized subcutaneously on days 1, 15 and 30 with B.aV/Na2EDTA (45, 90, 135 μg/mouse) or B.aV (15, 30, 45 μg/mouse), respectively. Both formulations were emulsified with Freund's adjuvant (complete first and incomplete-booster). Blood samples were collected from each mouse on days 14, 29, 41, and 50 post-first immunization, and serum was separated for antibody detection. Animals were then sacrificed and lungs removed for histological analysis (hematoxylin-eosin). Immunoblotting analysis revealed that the sera from mice inoculated with B.aV/Na2EDTA (anti-B.aV/Na2EDTA) recognized the major venom proteins (20–66 kDa) similarly to the sera from mice inoculated with B.aV (anti-B.aV). The enzyme-linked immunosorbent assay results indicated that the anti-B.aV/Na2EDTA had a higher titer (5.76 × 104) than those the anti-B.aV (1.92 × 104). Additionally, sera from animals immunized with B.aV/Na2EDTA significantly neutralized proteolytic, indirect hemolytic and coagulant activity (p < 0.05). Finally, histological examination of the lungs of mice inoculated with B.aV/Na2EDTA showed normal appearance, while animals inoculated with B.aV showed interstitial lung injury (p < 0.05). In conclusion, the B.aV/Na2EDTA formulation, free of excess Na2EDTA, proved to be a promising candidate as an immunogen for antivenom production.

Platelet aggregation inhibitors from Bothrops alternatus snake venom

Snake venoms are a complex mixture of proteins and peptides that can activate/inhibit platelet aggregation. Bothrops alternatus venom include three main families: metalloproteinases (SVMPs), serinoproteinases (SVSPs) and phospholipases A2 (PLA2s), among other minor components. In this work, we used inhibitor cocktails (containing Na2-EDTA, PMSF and/or pBPB) to investigate the effect of these three families and of baltergin (a PIII SVMP) on platelet aggregation by a turbidmetric method using a microplate reader. Cocktails 1 (active SVMPs) and 2 (active PLA2s) significantly reduced aggregation induced by ristocetin and collagen and by collagen and thrombin, respectively. Cocktail 3 (active SVSPs) showed a mild activation of aggregation, indicating the content of thrombin-like enzymes (TLEs) in this venom is low. Cocktail 4 (active minor components) displayed inhibitory effect with all agonists assayed (ristocetin, ADP, collagen and thrombin) but at higher IC50 values. Baltergin exhibited inhibitory effect when the catalytic domain was active for ristocetin-stimulated platelet aggregation and showed a non-enzymatic mechanism of inhibition when collagen was used as agonist. It was not able to disaggregate platelet thrombus. We conclude that B. alternatus venom is a source of natural inhibitors of platelet aggregation due to the action of SVMPs and PLA2s. Other minor components such as C-type lectins likely contribute to the antiplatelet effect. The interest in knowing the action of venom components on platelet function lies both in the understanding of the pathophysiology of snake bite envenomation and in their biotechnological application.

Full title: Inhibition of harmful effects from Bothrops alternatus venom by Casearia arborea extract

Full title: Inhibition of harmful effects from Bothrops alternatus venom by Casearia arborea extract

Photobiomodulation therapy on local effects induced by juvenile and adult venoms of Bothrops alternatus

Bothrops snake envenomation is characterized by severe local manifestations such as pain, edema, inflammation, hemorrhage, and myonecrosis. Furthermore, it is described that venom from juvenile and adult snakes may have differences in their composition that can lead to differences in the evolution of the clinical manifestation of the victim. Photobiomodulation (PBM) has been shown to be an effective adjuvant therapy to serum therapy to reduce the local effects induced by bothropic snake venom. This study evaluated the effect of PBM on the local reaction, after Bothrops alternatus snake venom (BaV) injection, in its juvenile (BaJV) and adult (BaAV) stages. Balb/C mice were injected with the juvenile or adult venoms of BaV or saline solution (control group). PBM at a wavelength of 660 nm, 100 mW, 0.33 W/cm2, 40 s, and a 0.028 cm2 beam was applied transcutaneous to a single point with a radiant exposure of 4 J/cm2, 30 min after venom injection. Edema, inflammatory infiltrate, hyperalgesia, and myonecrosis were analyzed. Both venoms induced significant edema and myonecrosis in the gastrocnemius muscle. Hyperalgesia in the mice paw and a prominent leukocyte infiltrate into the peritoneum were also observed. PBM significantly reduced all evaluated parameters. In conclusion, PBM treatment was effective in reducing the local effects induced by B. alternatus venom at different stages of snake development and could be a useful tool as an adjuvant treatment for bothropic envenomation.

Effects of cilostazol, a Phosphodiesterase-3 inhibitor, on kidney function and redox imbalance in acute kidney injury caused by Bothrops alternatus venom

The mechanisms of pathogenesis of acute kidney injury (AKI) in snakebites is multifactorial and involves hemodynamic disturbances, with release of free radical causing cytotoxic effects. The phosphodiesterase-3 (PDE3) inhibitor, Cilostazol, has been reported to provide protection against renal oxidative stress.Objective: We evaluated the protective effects of cilostazol against Bothrops alternatus snake venom (BaV)-induced nephrotoxicity.Methods: Wistar rat kidneys (n = 6, 260–300 g) were isolated and perfused with Krebs-Henseleit solution containing 6 g/100 mL of bovine serum albumin. After 30 min, the kidneys were perfused with BaV to a final concentration of 1 and 3 μg/mL, and subsequently evaluated for perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), and percentage of electrolyte tubular sodium and chloride transport (%TNa+, %TCl–). Oxidative stress and renal histological analyses were performed.Results:BaV caused a reduction in all the evaluated renal parameters (PP, RVR, GFR, UF, %TNa+, and %TCl–). Although only the effects on PP and UF were reversed with cilostazol treatment, the decrease in the malondialdehyde levels, without changes in glutathione levels, further reduced the venom-induced renal tissue changes.Conclusion: Our data suggest that PDE3 is involved in BaV-induced nephrotoxicity, as cilostazol administration significantly ameliorated these effects.

Alternagin-C, an alpha2beta1 integrin ligand, attenuates collagen-based adhesion, stimulating the metastasis suppressor 1 expression in triple-negative breast tumor cells

Triple-negative breast cancer has an aggressive clinical course and its treatment has been challenging due to high metastatic risk. Molecular targets have been sought to provide better strategies for this type of cancer. Integrins are cell adhesion receptors involved in tumor progression and α2β1 integrin, a collagen receptor, has a key role in breast metastasis. Disintegrins, a family of proteins from snake venoms, selectively block the function of integrin receptors. Alternagin-C (ALT-C), a disintegrin-like protein purified from Bothrops alternatus venom, binds to α2β1 integrin, attenuating inflammation and angiogenesis, and decreasing metalloprotease levels in the tumor microenvironment, which suggests anti-metastatic effects. However, its mechanisms of action in metastatic tumor cells have not been fully explored. Here, we investigated ALT-C effects in a triple-negative breast cancer cell line (MDA-MB-231) to elucidate how α2β1 integrin affects cellular adhesion, migration and gene expression related to metastasis. We observed that ALT-C attenuated cell adhesion of MDA-MB-231 cells to collagen I. α2 integrin subunit silencing in MDA-MB-231 cells did not inhibit cell adhesion and migration to collagen I, indicating that other integrins play a crucial role in cell motility for this cell line. ALT-C also stimulated the metastasis suppressor 1 (MTSS1) expression and decreased metalloproteases MMP9 and MMP2. Therefore, we suggest that ALT-C contributes to impair metastasis, preventing extracellular matrix degradation and tumor attachment to collagen I, increasing MTSS1. This study is the first to elucidate the anti-metastatic mechanism involving a disintegrin-like protein from snake venom targeting α2β1 integrin and stimulating a metastasis suppressor.

Hormetic-like dose-response induced by alternagin-C, a protein isolated from urutu snake (Rhinocerophis alternatus) venom, in fish (Hoplias malabaricus) cardiac contractility

The aim of this study was to evaluate the effects of different doses of alternagin-C, a disintegrin-like protein from Rhinocerophis alternatus venom, on myocardial contractility of the freshwater fish Hoplias malabaricus, an alternative model to contractile function studies. Alternagin-C treatment exhibited a hormetic-like dose-response curve with a strong positive inotropism and enhanced cardiac pumping capacity at low dose, whereas a modest inotropism and a left shift in the force-frequency relationship was registered at high dose.

Baltetin: a new C-type lectin-like isolated from Bothrops alternatus snake venom which act as a platelet aggregation inhibiting

C-type lectin-like proteins found in snake venom, known as snaclecs, have important effects on hemostasis through targeting membrane receptors, coagulation factors and other hemostatic proteins. Here, we present the isolation and functional characterization of a snaclec isolated from Bothrops alternatus venom, designated as Baltetin. We purified the protein in three chromatographic steps (anion-exchange, affinity and reversed-phase chromatography). Baltetin is a dimeric snaclec that is approximately 15 and 25 kDa under reducing and non-reducing conditions, respectively, as estimated by SDS-PAGE. Matrix-assisted laser desorption and ionization time-of-flight mass spectrometry and Edman degradation sequencing revealed that Baltetin is a heterodimer. The first 40 amino acid residues of the N-terminal region of Baltetin subunits share a high degree of sequence identity with other snaclecs. Baltetin had a specific, dose-dependent inhibitory effect on epinephrine-induced platelet aggregation in human platelet-rich plasma, inhibiting up to 69% of platelet aggregation. Analysis of the infrared spectra suggested that the interaction between Baltetin and platelets can be attributed to the formation of hydrogen bonds between the PO32- groups in the protein and PO2- groups in the platelet membrane. This interaction may lead to membrane lipid peroxidation, which prevents epinephrine from binding to its receptor. The present work suggests that Baltetin, a new C-type lectin-like protein isolated from B. alternatus venom, is the first snaclec to inhibit epinephrine-induced platelet aggregation. This could be of medical interest as a new tool for the development of novel therapeutic agents for the prevention and treatment of thrombotic disorders.

Antiophidic activity of the secondary metabolite lupeol isolated from Zanthoxylum monogynum

Previous studies have demonstrated the potential antiophidic activity of Zanthoxylum monogynum A.St.-Hil. a tree from the Rutaceae family native to South America. In this present contribution, we demonstrate the activity of the metabolite lupeol, a triterpenoid isolated from the stem bark of Z. monogynum against the harmful effects of the Bothrops alternatus venom. We investigated the antiophidic properties of lupeol, for this purpose, and use crude venom (Pb) incubated with lupeol in different concentrations, testing in vitro experiments and inoculated in mice for inhibitory evaluations in vivo. Besides, we tried to elucidate through the molecular dynamics the mechanism of action of lupeol with the bothropic thrombin-like toxin Jararacussin-I; the acidic phospholipase A2 toxin BthA-I from Bothrops jararacussu and the metalloproteinase toxin BmooMP-I from Bothrops moojeni. In our results, we demonstrated the potential inhibitory effect upon coagulant, phospholipasic and myotoxic activities of the bothropic venom, previously incubated with lupeol. We found that lupeol triterpenoid was able to partially inhibit local and systemic damage caused by snake venom toxins. Our in silico results demonstrate that lupeol is capable of interacting and altering the activity of the thrombin-like toxin Jararacussin-I, and capable of interacting with the BthA-I acidic PLA2, both toxins present in Bothrops snakes venom, thus demonstrating the pharmacological potential of this compound for the treatment of bothropic accidents.

Hemostatic evaluation of rabbits envenomed with Bothrops alternatus treated with anti-bothropic serum, desmopressin and tranexamin acid

ABSTRACT: In Brazil, snakes from the Bothrops genus are responsible for thousands of accidents, and their venoms are mainly composed of proteolytic enzymes. Although the antibothropic serum produced by the Brazilian Institutes is remarkably efficient, more studies are necessary, especially in veterinary medicine. The venom contain enzymes and non-enzymatic proteins that interfere with hemostasis leading to hemorrhage or even thrombosis. Possible treatment associations with known bothropic antivenom were the reason for the development of the present study. The aim of this study was to evaluate hemostasis alterations caused by Bothrops alternatus venom in rabbits followed by treatments with anti-bothropic serum, tranexamic acid and desmopressin. Twenty New Zealand rabbits were distributed into five groups (n=4) that were experimentally envenomed with 150mcg/kg of B. alternatus venom via intramuscular injection and treated as follow: Group 1 (G1) was the positive control and received venom and PBS/BSA; Group 2 (G2) was treated with tranexamic acid; Group 3 (G3) with desmopressin; Group 4 (G4) with tranexamic acid and anti-bothropic serum; and Group 5 (G5) with anti-bothropic serum and desmopressin. Blood samples were collected before venom administration, and one, four, eight and 12 hours after, for Partial activated partial thromboplastin time, Prothrombin Time, Thrombin Time and fibrinogen evaluation. Thrombin generation (TG) test was carried out with a pool of samples from final times (8 and 12h). At the end of 12h, all animals were euthanized and necropsy was conducted. Samples from muscle tissue, heart, lungs and kidney were analyzed. Classic coagulation tests showed no significant differences amongst groups and times. However, TG indicated that the venom causes a hypocoagulability state, which was not reversed by proposed treatments. Histology showed muscle inflammation, hemorrhage and necrosis, as well as hemorrhage in other tissues with no differences amongst groups. B. alternatus envenomation causes hypocoagulability detected by TG assay, but not through classical coagulation tests. The use of tranexamic acid and desmopressin for hemostasis stabilization after inoculation of the venom did not show advantage in coagulation restoration.

Use of alternative adjuvant systems to produce neutralizing IgY antibodies against Bothrops alternatus venom

Use of alternative adjuvant systems to produce neutralizing IgY antibodies against Bothrops alternatus venom

Inhibition by essential oils of Mentha viridis and Mentha pulegium (Lamiaceae) in proteolysis, fibrinogenolysis and coagulation caused by venomous snakes

Snake venom are widely used as laboratory tools for studies of physiological, pharmacological and toxicological mechanisms. Venoms used here are rich sources of several classes of proteases that act on factors of the coagulation cascade, fibrinogenolysis and fibrinolysis, altering the hemostatic processes, and phospholipases A2 which are involved mainly in inflammatory and clotting processes since they act hydrolyzing membrane phospholipids and may result in the release of arachidonic acid whose structure is a precursor of eicosanoids by cyclooxygenase and lipoxygenase pathways. Natural products such as essential oils are made up of active ingredients with wide application in the food, pharmaceutical and cosmetic industries. Thus, in this study evaluate the essential oils from Mentha viridis and Mentha pulegium on coagulation, fibrinogenolysis and degradation of azocasein, induced by Bothrops sp and Lachesis muta muta venoms. These oils were achieved by hydrodistillation and presented, respectively, as the main constituents linalool (40.70%), carvone (13.52%) and α-terpinene (8.56%); pulegone (50.01%), menthol (31.90%) and menthone (16.56%). The essential oils were previously incubated with Bothrops alternatus venom, for two different times, plasma was added and timing. The M. pulegium and M. viridis oils in the volume of 0.30 μL (10 min of incubation) presented greater anticlotting potential. Meanwhile, 0.15 μL the M. pulegium oil presented proclotting activity. In 20 min of incubation, both oils presented anticlotting activity with 0.15 and 0.30 μL. At azocaseinolytic assay the oil from M. pulegium reduced the activity for all evaluated venoms. The highest inhibitions were 34.33% and 39.99% for 0.6 and 1.2 μL of oil, respectively; on activity induced by B. jararacussu, M. viridis with 0.6 and 1.2 μL reduced the activity in 40.93% and 57.72%, respectively. On B. moojeni, the same volumes were responsible for inhibitions of 74.67% and 47.4%, respectively. The fibrinogenolysis induced by B. moojeni venom was totally inhibited by both oils in the evaluated proportions. The results show the presence in oils of protease inhibitors, considering metalloproteases (mainly with thrombin-like and hemorrhagic activity) and serineproteases (actuating on clotting factors), as well as phospholipase A2­ inhibitors (involved in inflammation and clotting processes) of wide application in medical and biotechnology areas.&#x0D;

Molecular interactions between p-coumaric acid and snake venom toxins.

A large number of natural compounds, such as phenolic compounds, have been scientifically evaluated in the search for enzyme inhibitors. The interactions between the phenolic compound p-coumaric acid and the enzymes present in snake venoms (used as research tools) were evaluated in vitro and in silico. The p-coumaric acid was able to inhibit 31% of the phospholipase activity induced by Bothrops alternatus venom, 27% of the hemolytic activity induced by B. moojeni, 62.5% of the thrombolytic activity induced by B. jararacussu, and approximately 27% of the activity thrombosis induced by Crotalus durissus terrificus. Previous incubation of p-coumaric acid with the venoms of B. atrox and B. jararacussu increased the coagulation time by 2.18 and 2.16-fold, respectively. The activity of serine proteases in B. atrox and B. jararacussu venoms was reduced by 60% and 66.34%, respectively. Computational chemistry analyses suggests the specific binding of p-coumaric acid to the active site of proteases through hydrogen and hydrophobic interactions. The phenolic compound evaluated in this work has great potential in therapeutic use to both prevent and treat hemostatic alterations, because the venom proteins inhibited by the p-coumaric acid have high homology with human proteins that have a fundamental role in several pathologies.

IgY-based antivenom against Bothrops alternatus: Production and neutralization efficacy

Antivenom for the treatment of bothropic snakebite is a priority for public health institutions from Latin America. An alternative to the conventional antivenom production is based on the use of egg yolk antibodies – IgY-technology – by immunizing laying hens. In this study, we produced, characterized and assessed the efficacy of IgY-based antivenoms against B. alternatus venom. Immunochemical studies (reactivity, avidity and antigen recognition pattern) as well as antivenom efficacy assays were performed. After the 3rd immunization, levels of specific IgY reached a maximum that was maintained throughout the observation period, while avidity indexes of the extracts increased after the successive immunizations. Furthermore, IgY against B. alternatus recognized protein complexes of the venom with high (>40 kDa), medium (20–40 kDa) and low (<20 kDa) molecular weights. IgY antivenoms obtained after 8 immunizations neutralized 35.65 μg of B. alternatus venom per mg of antivenom, while specific activities values ranged from 0.28 to 0.42. In conclusion, we produced and characterized IgY antivenoms capable of neutralizing the lethal activity of B. alternatus venom at a preclinical level. Thus, IgY-technology may allow the production of effective and affordable antivenoms fulfilling the urgent needs of many countries where conventional manufacture is unable to provide enough availability of antivenoms.

Use of EDTA in the treatment of local tissue damage caused by the Bothrops alternatus venom

ABSTRACT Twelve adult rabbits were distributed in three groups and received on the femoral biceps region, via intradermal injection (ID), 25µg of Bothrops alternatus venom dissolved in NaCl 0.9% and diluted in 0.25mL of phosphate buffered saline (PBS). Thirty minutes later, the group G1 received 0.25mL of phosphate buffered saline (PBS) ID while to G2 and G3 25mg of ethylenediamine tetraacetic acid (EDTA) dissolved in 0.25mL of PBS were administered via intramuscular (IM) and intravenous (IV) injection, respectively. Evaluations included local lesion and blood profile of all animals, before (time zero) and at 1, 2, 3, 4, 5, 6, 12, 18 and 24h after venom administration. All animal treated with PBS (G1) and EDTA IV (G3) presented increase of nociceptive stimuli at the site of inoculation of the venom, followed by moderate edema that persisted for 24h. Animals treated with IM EDTA (G2) only manifested increase of nociceptive stimuli at the site of injection 1h after treatment with discrete local edema between 12 and 24h. In relation to the local hemorrhagic halo no differences were found amongst the studied groups. Blood profile revealed significant decrease of segmented neutrophils in all groups. There was also increase in triglycerides and decrease in total protein and albumin in all groups. The local lesion was not altered by the treatments.

Could mesenchymal stem cell therapy help in the treatment of muscle damage caused by Bothrops alternatus venom?

ABSTRACT: The aim of this study was to evaluate the use of mesenchymal stem cells (MSC) in the treatment of myonecrosis induced by Bothrops alternatus venom in rats. Seventy-five male adult Wistar rats were divided into three experimental groups. G1 and G2 were injected in the gastrocnemius muscle with 120μg of B. alternatus venom, while G3 received 200μL of PBS only. Three days after the venom injection, 12 rats from G1 were treated with 5.0 x 106 MSC in PBS, whereas G2 and G3 rats received PBS. Every three days, blood and muscle samples of five animals from each group were taken for serum biochemical and pathological analyses. Histological examinations showed more intense muscle lesions following MSC treatment, characterized by disorganization and loss of muscle fibers, with focal necrosis and inflammatory infiltration by mononuclear cells. In conclusion, the use of MSC for the treatment of local damage caused by inoculation of B. alternatus venom impaired muscle regeneration and interfered in the healing process.

Purification of a fragment obtained by autolysis of a PIIIb-SVMP from Bothrops alternatus venom

Snake Venom Metalloproteinases (SVMPs) represent 43.1% of the components in Bothrops alternatus venom and play an important role in envenomation. Disintegrins and disintegrin-like domains are released by proteolytic processing of PII and PIII classes of SVMPs respectively and are potent inhibitors of integrin–ligand interaction. Baltergin is a PIIIb-SVMP isolated from this venom and able to undergo autolysis in vitro, giving rise to a stable disintegrin-like/cystein-rich fragment (baltergin-DC). Conditions of baltergin autolysis were adjusted in order to carry out the purification of baltergin-DC and its effect on cell adhesion was studied. Autolysis was maximal at 37°C and a pH range of 7.0–8.0. Baltergin-DC amino-terminal sequence begins with IISPPVCGNELLEVGEECDCGTPENCQNECCDAATC, which shows a high degree of homology with other disintegrin-like proteins. Baltergin and purified baltergin-DC were both able to inhibit C2C12 adhesion to fetal bovine serum (FBS) coated plates, indicating that a non-catalytic process is involved, probably mediated by binding to membrane integrins. Baltergin-DC, lacking proteolytic action, becomes an attractive molecule for future studies on blocking integrin–ligand interactions.

Effects of Bothrops alternatus venom in zebrafish: a histopathological study.

Zebrafish is an excellent model organism for studying tissue alterations caused by Bothrops alternatus venom (BAV) and for screening new anti-venom drugs. To study tissue alterations following exposure to BAV and the roles that glucocorticoids play in these tissue reactions, zebrafish were randomly divided into five groups: the free injection control group (FIC), the phosphate-buffered saline injection control group (PIC), the venom injected group (VI), the group treated with dexamethasone 1h before venom injection (D1hBVI) and the group treated with dexamethasone 1h after venom injection (D1hAVI). The concentration of BAV injected was 0.13mg/mL and each fish received an injection of 20 μL. Body weight measurements and histopathological characteristics of the gills, kidneys, liver, and intestine were determined. Histopathological analyses showed necrosis, inflammation and weight gain in animals that received BAV. The histological alteration indices of the gills, liver, kidneys, and intestines were statistically higher in the animal groups treated with BAV. These alteration indices were lower in the D1hBVI and D1hAVI groups compared to the group treated with BAV alone. The D1hBVI group is presented with minor alterations. A significant difference in the histological alterations index was observed in the intestinal tissue of the FIC group compared to the PIC group. Cumulatively, zebrafish may serve as a useful biomarker for alterations induced by BAV. Interestingly, dexamethasone reduced the damage caused by BAV in the organs studied, which suggests that zebrafish might be useful for screening new drugs that can mitigate tissue damage caused by snakebites.

Apoptosis induced by a snake venom metalloproteinase from Bothrops alternatus venom in C2C12 muscle cells.

In this study, the apoptosis inducing effects of baltergin as well as its influence on cell adhesion and migration on muscles cells in vitro were studied. Morphological analysis made by scanning electron and phase contrast microscopy demonstrated typical futures of programmed cell death, apoptosis. This mechanism was confirmed by fluorescence staining, molecular analysis of endonuclease activity and increased mRNA expression level of two representative genes (p53 and bax). On the other hand, baltergin exert an inhibition effect on myoblast cell adhesion and migration in vitro probably through a mechanism that involves the interaction of this enzyme with cell integrins. In conclusion, our results suggest that the absence of appropriate extracellular matrix contacts triggers anoikis. Therefore, this is the first report that demonstrated the mechanism of programmed cell death triggered by baltergin, a PIII metalloprotease isolated from Bothrops alternatus venom, in a myoblast cell line.

Acción local de vacunas elaboradas con veneno de &lt;i&gt;Bothrops alternatus&lt;/i&gt; en equinos productores de suero antiofídico

El objetivo del trabajo consistió en estudiar los efectos locales causados por sucesivas inoculaciones de veneno de Bothrops alternatus, en un grupo de tres equinos inmunizados para la producción de suero antiofídico monovalente. El adyuvante de Freund causó una respuesta importante para el estímulo inmunológico, en tanto que la inmunización con el veneno entero indujo sangrado local, edema, dolor y escape de enzimas del tejido muscular. La reacción local varió con las sucesivas vacunas, siendo constantes la hemorragia local y la inflamación, con formación de abscesos en las últimas inoculaciones. La actividad AST reveló elevaciones significativas de su tasa sérica, en tanto que LDH se incrementó de manera altamente significativa a partir de las 3 h con acmé a las 6 h y posterior descenso a las 24 h. En la primera vacunación, CPK se elevó significativamente a las 3 h y registró un segundo pico a las 24 h. Se observó una reducción de la magnitud de elevación de las actividades enzimáticas en las últimas inoculaciones (con altas dosis de veneno), quizás debido a que los anticuerpos preformados hayan conferido protección y reducido la destrucción de fibras musculares. Se concluye que los intensos efectos locales (dolor, hemorragia y posterior fibrosis local) imponen ensayar nuevas técnicas de inmunización a fin de minimizar los efectos adversos causados a los equinos.