Hump-Nosed Pit Viper Envenomation in Western Coastal India: A Case Series.

The hump-nosed pit viper (HNPV) has historically been considered less medically significant, causing local envenomation, renal injury, and coagulopathy; however, now, it is known to cause life-threatening complications. We describe the clinical presentation, treatment, and complications of 3 confirmed HNPV bites from the state of Karnataka (southwest coastal India). Patient 1, an 88-y-old woman, reported with the live specimen and developed venom-induced consumption coagulopathy (VICC) and thrombotic microangiopathy leading to acute kidney injury requiring blood product transfusions and dialysis. Patient 2, a 60-y-old woman, reported 3 d after envenomation followed by treatment at another hospital where 30 vials of polyvalent anti-snake venom (ASV) were given. She developed VICC and acute kidney injury requiring dialysis. On Day 9 of treatment, she developed a pontine hemorrhage. She died after a transfer to another treatment center closer to her residence. Patient 3, a 25-y-old man, was brought to our emergency department 6 h after being envenomed. He received topical ayurvedic treatment before arrival. He was unconscious and found to have severe VICC with a massive middle cerebral artery infarct. All 3 patients received Indian polyvalent ASV, which does not cover HNPV envenomation, clearly demonstrating the absence of paraspecificity and neutralization in a clinical setting. To our knowledge, Hypnale hypnale envenomation has not previously been reported from Karnataka state. The diagnosis of HNPV envenomation in a country without snake venom detection kits, under-reporting despite serious complications, financial burdens on rural populations afflicted, and poor outcomes due to the lack of a specific antivenom are discussed.

Pain and Cellular Migration Induced by Bothrops jararaca Venom in Mice Selected for an Acute Inflammatory Response: Involvement of Mast Cells.

Bothrops jararaca venom (BjV) can induce mast cell degranulation. In order to investigate the role of mast cells and the interference of the host genetic background in the inflammation induced by BjV, we have used mouse strains selected for maximal (AIRmax) or minimal (AIRmin) acute inflammatory response (AIR). Mice were pretreated with an inhibitor of mast cell degranulation, cromolyn (CROM), and injected in footpads or intraperitoneally (i.p.) with BjV. Pain was measured with von Frey hairs, cell migration in the peritoneum by flow cytometry, and reactive oxygen species (ROS) production by chemiluminescence assays. The nociceptive response to BjV was higher in AIRmax than AIRmin mice; however, this difference was abolished by pretreatment with CROM. BjV induced peritoneal neutrophil (CD11b+ GR-1+) infiltration and ROS secretion in AIRmax mice only, which were partially inhibited by CROM. Our findings evidence a role for mast cells in pain, neutrophil migration, and ROS production triggered by BjV in AIRmax mice that are more susceptible to the action of BjV.

Utilization of thromboelastograms in management of Crotalus adamanteus envenomation.

BACKGROUND: Crotalinae (pit viper) envenomations are frequently encountered in North American emergency departments. Cases can be complicated by ambiguity in initial species identification as well as timing and duration of current antivenin treatment. Recently, thromboelastography (TEG) has emerged as an enhanced real-time monitoring parameter for snake envenomations that may aid in management of venom-induced consumptive coagulopathy. CASE: A 61-year-old snake handler presented with severe coagulopathy and hypofibrinogenemia following envenomation from her pet eastern diamondback rattlesnake (Crotalus adamanteus). Her coagulopathy transiently improved with Crotalidae Polyvalent Immune Fab (Ovine) (FabAV) but would repeatedly rebound following cessation of antivenin over the next 10 days. Serial TEGs were successfully utilized to identify and corroborate fibrinolysis while predicting clot formation prior to routine coagulation studies. DISCUSSION: Traditional coagulation parameters have not always been ideal when treating severe coagulopathy from pit viper envenomations and may not identify active fibrinolysis for several hours. In this case of C. adamanteus envenomation, TEG proved to be useful in demonstrating improvements in clotting function prior to standard laboratory measures, which further guided antivenin therapy.

Correlating Fibrinogen Consumption and Profiles of Inflammatory Molecules in Human Envenomation's by Bothrops atrox in the Brazilian Amazon.

Snakebites are considered a major public health problem worldwide. In the Amazon region of Brazil, the snake Bothrops atrox (B. atrox) is responsible for 90% of the bites. These bites may cause local and systemic signs from acute inflammatory reaction and hemostatic changes, and present common hemorrhagic disorders. These alterations occur due the action of hemostatically active and immunogenic toxins which are capable of triggering a wide range of hemostatic and inflammatory events. However, the crosstalk between coagulation disorders and inflammatory reaction still has gaps in snakebites. Thus, the goal of this study was to describe the relationship between the consumption of fibrinogen and the profile of inflammatory molecules (chemokines and cytokines) in evenomations by B. atrox snakebites. A prospective study was carried out with individuals who had suffered B. atrox snakebites and presented different levels of fibrinogen consumption (normal fibrinogen [NF] and hypofibrinogenemia [HF]). Seventeen patients with NF and 55 patients with HF were eligible for the study, in addition to 50 healthy controls (CG). The molecules CXCL-8, CCL-5, CXCL-9, CCL-2, CXCL-10, IL-6, TNF, IL-2, IL-10, IFN-γ, IL-4, and IL-17A were quantified in plasma using the CBA technique at three different times (pre-antivenom therapy [T0], 24 h [T1], and 48 h [T2] after antivenom therapy). The profile of the circulating inflammatory response is different between the groups studied, with HF patients having higher concentrations of CCL-5 and lower IFN-γ. In addition, antivenom therapy seems to have a positive effect, leading to a profile of circulating inflammatory response similar in quantification of T1 and T2 on both groups. Furthermore, these results suggest that a number of interactions of CXCL-8, CXCL-9, CCL-2, IL-6, and IFN-γ in HF patients are directly affected by fibrinogen levels, which may be related to the inflammatory response and coagulation mutual relationship induced by B. atrox venom. The present study is the first report on inflammation-coagulation crosstalk involving snakebite patients and supports the better understanding of envenomation's pathophysiology mechanisms and guides in the search for novel biomarkers and prospective therapies.

Crotalus oreganus concolor: Envenomation Case with Venom Analysis and a Diagnostic Conundrum of Myoneurologic Symptoms.

A case of midget-faded rattlesnake (Crotalus oreganus concolor) envenomation of an adult male professional herpetologist occurred in a rural setting and resulted in an array of venom induced myoneurologic symptoms. The patient experienced blurry vision, total body paresthesia, dyspnea, chest tightness, and waves of spastic muscle movements of the hands and feet that resembled tetany. It was not apparent whether these symptoms were potentially venom induced or were related to stress-induced physiologic responses. Local envenomation effects were minimal, and coagulation parameters remained within normal limits. Antivenom was not administered per patient concerns related to a history of acute allergic reactions to antivenom. Venom was collected from the Crotalus oreganus concolor responsible for the bite, and analysis revealed the presence of high levels of myotoxins (SR calcium pump antagonists) and concolor toxin, a presynaptic neurotoxin that can have myotoxic effects and cause respiratory paralysis; several serine proteinases associated with coagulopathies were also present in the venom profile.

Acute kidney injury caused by the intraperitoneal injection of Bothrops jararaca venom in rats.

We examined the ability of Bothrops jararaca venom (12.5 mg/kg) injected intraperitoneally (i.p.) to cause acute kidney injury (AKI) in rats. Blood urea and creatinine (AKI biomarkers, in g dL-1) were elevated after 2 h in venom-treated rats (urea: from 0.41 ± 0.1 to 0.7 ± 0.03; creatinine from 46.7 ± 3.1 to 85 ± 6.7; p < 0.05; n = 3 each), with no change in circulating reduced glutathione. Venom-treated rats survived for ∼6 h, at which point platelets were reduced (×103 µL-1; from 763.8 ± 30.2 to 52.5 ± 18.2) whereas leukocytes and erythrocytes were slightly increased (from 4.7 ± 0.3 to 6.6 ± 0.1 × 103 µL-1 and from 8.38 ± 0.1 to 9.2 ± 0.09 × 106 µL-1, respectively; p < 0.05); blood protein (5.2 ± 0.4 g dL-1) and albumin (2.7 ± 0.1 g dL-1) were normal, whereas blood and urinary urea and creatinine were increased. All parameters returned to normal with antivenom given 2 h post-envenomation. The i.p. injection of venom caused AKI similar to that seen with other routes of administration.

Clinical, Laboratory, and Therapeutic Aspects of Crotalus durissus (South American Rattlesnake) Victims: A Literature Review.

Snakebite envenoming is a neglected public health issue in many tropical and subtropical countries. To diagnosis and treat snakebites may be challenging to health care personnel since sufficient information has not been yet provided. This review presents the clinical, therapeutic, and laboratory aspects of Crotalus durissus (South American rattlesnakes) victims. The clinical setting may show local effects such as little or no pain, mild edema, and recurrent erythema. In contrast, the systemic effects may be quite remarkable, such as changes due to neurological damage, intense rhabdomyolysis, incoagulability of the blood, and variations in the peripheral blood elements. The main complication is acute kidney injury. The appropriate treatment depends mainly on the correct recognition of the aggressor snake and the symptoms expressed by the victim. Rattlesnake venom can cause irreparable damage and lead to death. Therefore, a prompt diagnosis allows the immediate onset of proper serotherapy.

Alteraciones hemostáticas provocadas por el veneno de la culebra mapanare (Porthidium lansbergii hutmanni) en pacientes venezolanos / Haemostatic alterations caused by the venom of Lansberg's hognosed pitviper (Porthidium lansbergii hutmanni) in Venezuelan patients

Objective: to describe the haemostatic characteristics of the venom as well as the potency appraisal of the polyvalent antiophidic serum against haemotoxicity from Porthidium lansbergii hutmani experimental envenomation. Methods: Evaluation was performed of the venom's lethality, haemorrhagic activity, effects on coagulation and platelet aggregation, proteolytic activity, and neutralization by the commercial antivenom available in the country. Results: Several components with haemostatic activities were found in Porthidium l. hutmanni venom when a study of fibrinogenolytic, haemorrhagic and proteolytic activities was conducted of a pool of P.l.h venom. Porthidium l. hutmanni venom lacked the coagulant and defibrinating activities that are characteristic of bothropic venoms. Porthidium l. hutmanni venom showed very high haemorrhagic and anticoagulant activities. These findings could be related to the presence of multiple metalloproteases, which was evidenced in this study, and also the possible presence of phospholipases or other anticoagulant activity proteins that were not defined here. They inhibited platelet aggregation, suggesting that the venom had some proteins with marked effects on haemostasis. The commercial antivenom proved to be of little effectiveness in neutralizing the crude venom haemorrhagic activity. Conclusions: These toxins cause many physiopathological alterations in bitten patients, creating a clinical picture characterized by oedema, local and systemic haemorrhages, and even necrosis, comparable to that seen in bothropic envenomation. Porthidium l. hutmanni venom has no in vitro procoagulant activity, typical of bothropic venoms, suggesting there are variances in its protein conformation. Porthidium l. hutmanni venom is used for horse immunization. However, in order to preserve the patient's life, it is necessary to improve the immunization process to produce antivenom containing high avidity and specificity antibodies against the major toxins present in this venom. Porthidium l. hutmanni venom has demonstrated being a venom with high lethal, haemorrhagic, proteolytic and procoagulant activities, whose description will have enormous utility among clinicians who deal with these accidents in its geographical distribution areas(AU)

Objetivo: Describir las características hemostáticas del veneno y evaluar la potencia del suero polivalente antiofídico contra la hemotoxicidad provocada por el envenenamiento experimental por Porthidium lansbergii hutmanni. Métodos: Se realizó una evaluación de la letalidad, actividad hemorrágica, efectos en la coagulación y agregación plaquetaria, actividad proteolítica y neutralización por el antiveneno disponible comercialmente en el país. Resultados: Se encontraron varios componentes con actividad hemostática en el veneno de Porthidium l. hutmanni al realizarse un estudio de la actividad fibrinogenolítica, hemorrágica y proteolítica de una muestra de veneno de Porthidium l. hutmanni. El veneno de Porthidium l. hutmanni no mostró la actividad coagulante o defibrinante característica de los venenos botrópicos. El veneno de Porthidium l. hutmanni mostró una elevada actividad hemorrágica y anticoagulante. Estos resultados podrían estar relacionados con la presencia de múltiples metaloproteasas, la que quedó demostrado en el estudio, y también a la posible presencia de fosfolipasas u otras proteínas de actividad anticoagulante que no se definen en el mismo. La inhibición de la agregación plaquetaria sugiere que el veneno contiene algunas proteínas con un marcado efecto sobre la hemostasis. El antiveneno comercial mostró poca efectividad en la neutralización de la actividad hemorrágica del veneno crudo. Conclusiones: Estas toxinas provocan muchas alteraciones fisiopatológicas en las víctimas de mordeduras, creando un cuadro clínico caracterizado por edema, hemorragias locales y sistémicas e incluso necrosis comparable con la que ocurre en el envenenamiento botrópico. El veneno de Porthidium l. hutmanni no tiene la actividad procoagulante in vitro típica de los venenos botrópicos, lo que apunta a variaciones en su conformación proteica. El veneno de Porthidium l. hutmanni de utiliza en la inmunización de los caballos. Sin embargo, para preservar la vida del paciente, es necesario mejorar el proceso de inmunización con vistas a producir un antiveneno que contenga anticuerpos de elevada avidez y especificidad contra las principales toxinas presentes en el veneno. El veneno de Porthidium l. hutmanni ha mostrado ser un veneno de elevada actividad letal, hemorrágica, proteolítica y procoagulante, cuya descripción tendrá una enorme utilidad para los médicos que atienden esos accidentes en sus áreas de distribución geográfica(AU)

Long term safety of targeted internalization of cell penetrating peptide crotamine into renal proximal tubular epithelial cells in vivo.

Activated proximal tubular epithelial cells (PTECs) play a crucial role in progressive tubulo-interstitial fibrosis in native and transplanted kidneys. Targeting PTECs by non-viral delivery vectors might be useful to influence the expression of important genes and/or proteins in order to slow down renal function loss. However, no clinical therapies that specifically target PTECs are available at present. We earlier showed that a cationic cell penetrating peptide isolated from South American rattlesnake venom, named crotamine, recognizes cell surface heparan sulfate proteoglycans and accumulates in cells. In healthy mice, crotamine accumulates mainly in kidneys after intraperitoneal (ip) injection. Herein we demonstrate for the first time, the overall safety of acute or long-term treatment with daily ip administrated crotamine for kidneys functions. Accumulation of ip injected crotamine in the kidney brush border zone of PTECs, and its presence inside these cells were observed. In addition, significant lower in vitro crotamine binding, uptake and reporter gene transport and expression could be observed in syndecan-1 deficient HK-2 PTECs compared to wild-type cells, indicating that the absence of syndecan-1 impairs crotamine uptake into PTECs. Taken together, our present data show the safety of in vivo long-term treatment with crotamine, and its preferential uptake into PTECs, which are especially rich in HSPGs such as syndecan-1. In addition to the demonstrated in vitro gene delivery mediated by crotamine in HK-2 cells, the potential applicability of crotamine as prototypic non-viral (gene) delivery nanocarrier to modulate PTEC gene and/or protein expression was confirmed.

Case Report: Bothrops lanceolatus Snakebite Surgical Management-Relevance of Fasciotomy.

Bothrops lanceolatus is an endemic Crotalidae species in Martinique, where approximately 30 cases of envenoming are managed yearly. Envenoming characteristics from Bothrops species include local tissue damage, systemic bleeding, and hemodynamic alterations. We hereby report a case of severe envenomation following B. lanceolatus snakebite to the right calf. Severe local manifestations developed progressively up to the lower limb despite adequate antivenom therapy. Systemic manifestations of venom also occurred, resulting in intensive care therapy. Surgery exploration revealed soft tissue necrosis, friability of the deep fascia, and myonecrosis. The patient needed multiple debridement procedures and fasciotomy of all leg compartments and anterior compartment of the thigh. Diagnosis of necrotizing fasciitis was confirmed by positive Aeromonas hydrophila blood cultures. This clinical case illustrates that major soft tissue infection, including necrotizing fasciitis may occur after snakebite. Abnormal coagulation tests should not delay surgical management, as severe envenoming is a life-threatening condition.

Edema Induced by a Crotalus durissus terrificus Venom Serine Protease (Cdtsp 2) Involves the PAR Pathway and PKC and PLC Activation.

Snake venom serine proteases (SVSPs) represent an essential group of enzymatic toxins involved in several pathophysiological effects on blood homeostasis. Some findings suggest the involvement of this class of enzymatic toxins in inflammation. In this paper, we purified and isolated a new gyroxin isoform from the Crotalus durissus terrificus (Cdt) venom, designated as Cdtsp 2, which showed significant proinflammatory effects in a murine model. In addition, we performed several studies to elucidate the main pathway underlying the edematogenic effect induced by Cdtsp 2. Enzymatic assays and structural analysis (primary structure analysis and three-dimensional modeling) were closely performed with pharmacological assays. The determination of edematogenic activity was performed using Cdtsp 2 isolated from snake venom, and was applied to mice treated with protein kinase C (PKC) inhibitor, phospholipase C (PLC) inhibitor, dexamethasone (Dexa), antagonists for protease-activated receptors (PARs), or saline (negative control). Additionally, we measured the levels of cyclooxygenase 2 (COX-2), malondialdehyde (MDA), and prostaglandin E2 (PGE2). Cdtsp 2 is characterized by an approximate molecular mass of 27 kDa, an isoelectric point (pI) of 4.5, and significant fibrinolytic activity, as well as the ability to hydrolyze Nα-benzoyl-l-arginine 4-nitroanilide (BAPNA). Its primary and three-dimensional structures revealed Cdtsp 2 as a typical snake venom serine protease that induces significant edema via the metabolism of arachidonic acid (AA), involving PARs, PKC, PLC, and COX-2 receptors, as well as inducing a significant increase in MDA levels. Our results showed that Cdtsp 2 is a serine protease with significant enzymatic activity, and it may be involved in the degradation of PAR1 and PAR2, which activate PLC and PKC to mobilize AA, while increasing oxidative stress. In this article, we provide a new perspective for the role of SVSPs beyond their effects on blood homeostasis.

Hyponatraemia and seizures in Merrem's hump-nosed pit viper (Hypnale hypnale) envenoming: a case report.

BACKGROUND: Hump-nosed pit vipers (Genus: Hypnale) are medically important snakes in Sri Lanka and South India. Merrem's Hump-nosed pit viper (Hypnale hypnale) frequently leads to potentially fatal envenomings in Sri Lanka and India. Venom-induced consumption coagulopathay (VICC), local envenoming and acute kidney injury (AKI) are the commonest effects of the envenoming by this snake. CASE PRESENTATION: We report a previously unreported presentation of H. hypnale envenoming, with an isolated urinary salt loss leading to moderate hyponatraemia resulting seizures. The patient was treated with careful fluid and electrolyte management. No antivenom is currently available for H. hypnale envenoming. CONCLUSION: In the absence of any evidence of venom induced consumptive coagulopathy, acute kidney injury and cerebral haemorrhage, we hypothesize that this effect is likely due to the presence of a natriuretic peptide in H. hypnale venom, similar to the natriuretic peptides identified in few other snake venoms.

Resource Utilization After Snakebite Severity Score Implementation into Treatment Algorithm of Crotaline Bite.

BACKGROUND: Crotaline envenomation clinical manifestations vary considerably among patients. Current recommendations for treatment with Crotalidae polyvalent immune Fab require assessment of envenomation control. Determining control of envenomation, particularly when patients are evaluated by different providers in separate clinical settings, can be difficult. OBJECTIVE: To determine if a difference in total vials of Crotalidae antivenin therapy exists between pre-protocol and post-Snakebite Severity Score (SSS) protocol. METHODS: Retrospective medical record review at an academic medical and regional Level I trauma center. Resource utilization in patients with a diagnosis of "snakebite" was compared between patients treated pre- and post-SSS protocol implementation. RESULTS: One hundred forty-six patients were included in the evaluation. One hundred twenty-seven (87.0%) patients received antivenin, n = 80 (90.9%) in the pre-protocol group and n = 47 (81.0%) in the post-protocol group. Median total number of antivenin vials per patient was lower in the post-protocol group than the pre-protocol group, 16 (10-24 interquartile range) vs. 12 (10-16 interquartile range), p = 0.006. This decreased utilization correlates to an approximate $13,200 savings per patient. Hospital and intensive care unit length of stay, opioid use, incidence of blood product transfusion, need for surgical intervention, or need for intubation were not different between groups. CONCLUSIONS: A snakebite protocol with SSS utilization to guide antivenin administration results in significantly decreased antivenin therapy in snakebite patients without increase in other health care utilization.

Fibrosis-Inducing Strategies in Regenerating Dystrophic and Normal Skeletal Muscle.

The excessive accumulation of collagens (fibrosis) impairs the function of vital tissues and organs. Fibrosis is a hallmark of severe muscular dystrophies, such as the incurable Duchenne Muscular Dystrophy (DMD), where skeletal muscle is substituted by scar (fibrotic) tissue as disease advances. One of the major obstacles in increasing our ability to combat fibrosis-driven muscular dystrophy progression is that no optimal in vivo models of muscle fibrosis are currently available, limiting fibrosis research and the development of novel therapies. In this chapter we describe different experimental strategies to accelerate and enhance muscle fibrosis in vivo in the widely used animal model for DMD, the mdx mouse. Since excessive tissue scarring also hampers the normal regeneration process after muscle injury, we have extended these fibrogenic strategies to the muscle of normal (non-diseased) mice. These strategies will allow fibrosis induction and assessment in a wide array of genetically modified mouse lines in physiological and pathological conditions of muscle regeneration. They should eventually improve our ability to combat fibrosis and foster muscle regeneration in DMD.

Severe Pit Viper Envenomation with Extended Clinical Signs and Treatment Complications in a Dog.

This manuscript describes the extended clinical abnormalities that can occur in severe snake envenomation and the clinical signs associated with antivenom hypersensitivity in a 3 yr old dog. Treatment consisted of IV fluid therapy, analgesics, a vasopressor, cardiac antiarrhythmia drugs, and polyvalent pit viper antivenom. Following initial response to treatment, relapse of clinical signs occurred. Most interesting was the recrudescence of clinical signs on day 7 that may have been caused by the release of deposited venom during surgical debridement of necrotic skin. The resulting extensive clinical signs required multiple vials of antivenom (22 vials over a 7 day period). Both F(ab')2 antivenom and antivenin (Crotalidae) polyvalent were used in this dog because of availability logistics. It is thought that this large amount of antivenom resulted in type I (anaphylaxis) and type III hypersensitivity (serum sickness) reactions. The dog made a complete clinical recovery. This description of extended, fluctuating clinical abnormalities that were associated with envenomation together with the development of hypersensitivity reactions that were presumably secondary to antivenom administration is information that can be useful for the management of patients afflicted with severe pit viper envenomation.

Influence of thyroid states on the local effects induced by Bothrops envenoming.

Bothrops leucurus venom causes significant local effects, such as necrosis, pain, hemorrhage and edema. These effects are important because of their high frequency and severity. The treatment of these local effects is not simple because of their quick triggering and a variety of components that induce these effects. Myonecrosis, dermonecrosis and edema are primarily caused by the action of hemorrhagins and myotoxins. A number of investigators have demonstrated the influence of thyroid hormones on inflammatory processes, particularly on wound healing. We investigated the edematogenic, hemorrhagic and necrotic activity of the B. leucurus venom in the hypothyroid, hyperthyroid and euthyroid of rats. The CK (creatine kinase) plasma level decreased in the animals in a hypothyroid state. The hypothyroid condition also significantly reduced the hemorrhagic and dermonecrotic area compared to the euthyroidism and hyperthyroidism states. It also mitigated the rat paw edema compared to that found in the euthyroid and hyperthyroid animals. The hyperthyroid animals showed no significant differences in the three treatments compared to the euthyroid animals. Our results suggest that the triggering of local effects induced by envenomation by B. leucurus is attenuated in hypothyroid animals, possibly by the effect of hypothyroidism on the immune system and blood flow.

Intrahippocampal infusion of crotamine isolated from Crotalus durissus terrificus alters plasma and brain biochemical parameters.

Crotamine is one of the main constituents of the venom of the South American rattlesnake Crotalus durissus terrificus. Here we sought to investigate the inflammatory and toxicological effects induced by the intrahippocampal administration of crotamine isolated from Crotalus whole venom. Adult rats received an intrahippocampal infusion of crotamine or vehicle and were euthanized 24 h or 21 days after infusion. Plasma and brain tissue were collected for biochemical analysis. Complete blood count, creatinine, urea, glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), creatine-kinase (CK), creatine kinase-muscle B (CK-MB) and oxidative parameters (assessed by DNA damage and micronucleus frequency in leukocytes, lipid peroxidation and protein carbonyls in plasma and brain) were quantified. Unpaired and paired t-tests were used for comparisons between saline and crotamine groups, and within groups (24 h vs. 21 days), respectively. After 24 h crotamine infusion promoted an increase of urea, GOT, GPT, CK, and platelets values (p ≤ 0.01), while red blood cells, hematocrit and leukocytes values decreased (p ≤ 0.01). Additionally, 21 days after infusion crotamine group showed increased creatinine, leukocytes, TBARS (plasma and brain), carbonyl (plasma and brain) and micronucleus compared to the saline-group (p ≤ 0.01). Our findings show that crotamine infusion alter hematological parameters and cardiac markers, as well as oxidative parameters, not only in the brain, but also in the blood, indicating a systemic pro-inflammatory and toxicological activity. A further scientific attempt in terms of preserving the beneficial activity over toxicity is required.

The intrahippocampal infusion of crotamine from Crotalus durissus terrificus venom enhances memory persistence in rats.

Previous research has shown that crotamine, a toxin isolated from the venom of Crotalus durissus terrificus, induces the release of acetylcholine and dopamine in the central nervous system of rats. Particularly, these neurotransmitters are important modulators of memory processes. Therefore, in this study we investigated the effects of crotamine infusion on persistence of memory in rats. We verified that the intrahippocampal infusion of crotamine (1 µg/µl; 1 µl/side) improved the persistence of object recognition and aversive memory. By other side, the intrahippocampal infusion of the toxin did not alter locomotor and exploratory activities, anxiety or pain threshold. These results demonstrate a future prospect of using crotamine as potential pharmacological tool to treat diseases involving memory impairment, although it is still necessary more researches to better elucidate the crotamine effects on hippocampus and memory.

Coagulopathy as the main systemic manifestation after envenoming by a juvenile South American rattlesnake (Crotalus durissus terrificus): case report.

CONTEXT: Rattlesnake bites in Brazil are generally caused by adult individuals, with most of the envenomed patients showing systemic manifestations that include varying degrees of neurotoxicity (acute myasthenia), rhabdomyolysis and coagulopathy, with only mild or no local manifestations. We report a case of envenoming by a juvenile South American rattlesnake (Crotalus durissus terrificus) that involved coagulopathy as the main systemic manifestation. CASE DETAILS: A 19-year-old male was admitted to our Emergency Department with coagulopathy (incoagulable PT, APTT and INR), no remarkable local manifestations and no signs/symptoms of myasthenia or rhabdomyolysis (serum CK, LDH, ALT and AST within reference levels) 5 days after being bitten by a small snake that was described as a rattlesnake but was not brought for identification at admission. The patient had already been treated in another Emergency Department with i.v. bothropic antivenom (AV) 1 h and 4 days post-bite. Based on the possibility of an unusual rattlesnake bite, crotalic AV was administered i.v., which improved the coagulation (9 h post-CroAV, INR = 2.11; 36 h post-CroAV, INR = 1.42). During hospitalization, relatives brought the snake that caused the bite, which was identified as a 38-cm long C. d. terrificus. DISCUSSION: Little is known about the clinical manifestations after bites by juvenile C. d. terrificus. This case shows that systemic envenoming by juvenile C. d. terrificus may result in coagulopathy as the main systemic manifestation, without neuromyotoxic features normally associated with bites by adult specimens. Despite the delayed administration, crotalic AV was effective in improving the blood coagulation.

Antiophidic activity of the extract of the Amazon plant Humirianthera ampla and constituents.

ETHNOPHARMACOLOGICAL RELEVANCE: Although serotherapy against snakebite has been discovered more than one hundred years ago, antivenom is not available all over Brazil. The use of plants from folk medicine is common mainly in the Brazilian Amazon area. One of these plants is named Humirianthera ampla (HA). MATERIALS AND METHODS: We have investigated HA extract and constituents' antiophidic activity in different experimental protocols against some Bothrops snake venoms (Bothrops jararacussu, Bothrops atrox and Bothrops jararaca). The protocols investigated include phospholipase, proteolytic, pro-coagulant, hemorrhagic, edematogenic and myotoxic activities induced by these venoms in Swiss mice. RESULTS: All the venoms caused an increase in the rate of creatine kinase (CK) release from isolated muscles, indicating damage to the sarcolemma. The crude extract of HA decreased the myotoxic activity in a concentration-dependent fashion. The presence of HA 300 µg/mL decreased up to 96% of Bothrops jararacussu and 94% of Bothrops atrox myotoxicity after 90 min of exposure. In vivo myotoxicity of Bothrops atrox venom was decreased in 75% when the venom was preincubated with HA 500 mg/kg. Similar results were observed with lupeol against Bothrops jararacussu and Bothrops atrox venoms. The hemorrhagic activity was evaluated by intradermal injection of Bothrops atrox venom. Preincubation and oral pre- and posttreatment with HA decreased hemorrhage by 100%, 45% and 45%, respectively. Bothrops atrox venom also induced formation of edema, which was significantly inhibited by pre- and posttreatment with HA. All the venoms showed extensive pro-coagulating properties, and these activities were inhibited by up to 90% with HA, which presented concentration-dependent inhibition. Finally, proteolytic and phospholipase activities of the venoms were all inhibited by increasing concentrations of HA, lupeol and sitosterol. The inhibition of these activities might help explain the actions against in vivo myotoxicity and the in vivo effects observed, i.e., edema, myotoxicity, pro-coagulation and hemorrhage. CONCLUSIONS: Altogether, our results give support for the popular use of HA extracts in cases of accidents with snakes, suggesting that it can be used as an adjunct in the management of venomous snakebites.