RESUMEN
BACKGROUND: The venom of Crotalus durissus terrificus, as well as its fractions, has intrigued research groups worldwide who are working to isolate, characterize, and find possible biotechnological applications. A number of studies have elucidated that these fractions and their derivatives possess pharmacological properties, which can enable the development of new drug prototypes with anti-inflammatory, antinociceptive, antitumor, antiviral, and antiparasitic applications. OBJECTIVE: This review presents a systematic study on Crotalus durissus terrificus, the most notable crotalid subspecies in South America, focusing on the composition, toxicological mechanisms, structural aspects, and applications of the main venom toxins (convulxin, gyroxin, crotamine, crotoxin, and their subunits). CONCLUSION: The authors have found that research on this snake and its toxins is still an area of focus, despite that almost a century has passed since the isolation of crotoxin. Several applications of these proteins in the development of novel drugs and bioactive substances have also been demonstrated.
Asunto(s)
Venenos de Crotálidos , Crotoxina , Animales , Crotoxina/farmacología , Crotoxina/uso terapéutico , Crotoxina/química , Crotalus , Venenos de Crotálidos/química , América del Sur , BiologíaRESUMEN
Multiple sclerosis (MS) is a Central Nervous System inflammatory demyelinating disease that has as primary symptoms losses of sensory and motor functions, including chronic pain. To date, however, few studies have investigated the mechanisms of chronic pain in animal models of MS since locomotor impairments render difficult its evaluation. It was previously demonstrated that in the MOG35-55-induced EAE, an animal model of MS, the hypernociception appears before the onset of motor disability, allowing for the study of these two phenomena separately. Here, we evaluated the effect of crotoxin (CTX), a neurotoxin isolated from the Crotalus durissus terrificus snake venom that displays, at non-toxic dose, antinociceptive, anti-inflammatory and immunomodulatory effects, in the pain and in symptoms progression of EAE. The pain threshold of female C57BL/6 mice decreased at the 4th day after immunization, while the first sign of disease appeared around the 11st-12nd days, coinciding with the onset of motor abnormalities. CTX (40 µg/kg, s.c.) administered in a single dose on the 5th day after immunization, induced a long-lasting analgesic effect (5 days), without interfering with the clinical signs of the disease. On the other hand, when crotoxin was administered for 5 consecutive days, from 5th-9th day after immunization, it induced analgesia and also reduced EAE progression. The antinociceptive effect of crotoxin was blocked by Boc-2 (0.5 mg/kg, i.p.), a selective antagonist of formyl peptide receptors, by NDGA (30 µg/kg, i.p.), a lipoxygenase inhibitor and by atropine sulfate (10 mg/kg, i.p.), an antagonist of muscarinic receptors, administered 30 min before CTX. CTX was also effective in decreasing EAE clinical signs even when administered after its onset. Regarding the interactions between neurons and immunocompetent cells, CTX, in vitro, was able to reduce T cell proliferation, decreasing Th1 and Th17 and increasing Treg cell differentiation. Furthermore, in EAE model, the treatment with 5 consecutive doses of CTX inhibited IFN-γ-producing T cells, GM-CSF-producing T cells, reduced the frequency of activated microglia/macrophages within the CNS and decreased the number of migrating cell to spinal cord and cerebellum at the peak of the disease. These results suggest that CTX is a potential treatment not only for pain alteration but also for clinical progression induced by the disease as well as an useful tool for the development of new therapeutic approaches for the multiple sclerosis control.
Asunto(s)
Crotoxina , Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Dolor , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Crotoxina/farmacología , Crotoxina/uso terapéutico , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , Dolor/tratamiento farmacológico , Dolor/etiologíaRESUMEN
Neuropathic pain is a disease caused by structural and functional plasticity in central and peripheral sensory pathways that produce alterations in nociceptive processing. Currently, pharmacological treatment for this condition remains a challenge. Crotoxin (CTX), the main neurotoxin of Crotalus durissus terrificus rattlesnake venom, has well described prolonged anti-inflammatory and antinociceptive activities. In spite of its potential benefits, the toxicity of CTX remains a limiting factor for its use. SBA-15 is an inert nanostructured mesoporous silica that, when used as a vehicle, may reduce toxicity and potentiate the activity of different compounds. Based on this, we propose to conjugate crotoxin with SBA-15 (CTX:SBA-15) in order to investigate if when adsorbed to silica, CTX would have its toxicity reduced and its analgesic effect enhanced in neuropathic pain induced by the partial sciatic nerve ligation (PSNL) model. SBA-15 enabled an increase of 35% of CTX dosage. Treatment with CTX:SBA-15 induced a long-lasting reduction of mechanical hypernociception, without modifying the previously known pathways involved in antinociception. Moreover, CTX:SBA-15 reduced IL-6 and increased IL-10 levels in the spinal cord. Surprisingly, the antinociceptive effect of CTX:SBA-15 was also observed after oral administration. These data indicate the potential use of the CTX:SBA-15 complex for neuropathic pain control and corroborates the protective potential of SBA-15.
Asunto(s)
Analgésicos/uso terapéutico , Crotoxina/uso terapéutico , Neuralgia/tratamiento farmacológico , Dióxido de Silicio/uso terapéutico , Analgésicos/administración & dosificación , Analgésicos/efectos adversos , Animales , Crotoxina/administración & dosificación , Crotoxina/efectos adversos , Hiperalgesia/tratamiento farmacológico , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Nanoestructuras , Nocicepción/efectos de los fármacos , Neuropatía Ciática/tratamiento farmacológico , Dióxido de Silicio/administración & dosificación , Dióxido de Silicio/efectos adversos , Médula Espinal/metabolismoRESUMEN
For the past 80 years, Crotoxin has become one of the most investigated isolated toxins from snake venoms, partially due to its major role as the main toxic component in the venom of the South American rattlesnake Crotalus durissus terrificus. However, in the past decades, progressive studies have led researchers to shift their focus on Crotoxin, opening novel perspectives and applications as a therapeutic approach. Although this toxin acts on a wide variety of biological events, the modulation of immune responses is considered as one of its most relevant behaviors. Therefore, the present review describes the scientific investigations on the capacity of Crotoxin to modulate anti-inflammatory and immunosuppressive responses, and its application as a medicinal immunopharmacological approach. In addition, this review will also discuss its mechanisms, involving cellular and molecular pathways, capable of improving pathological alterations related to immune-associated disorders.(AU)
Asunto(s)
Animales , Crotalus cascavella , Crotoxina/inmunología , Crotoxina/uso terapéutico , Inmunosupresores , Inmunidad Innata , Inmunidad Adaptativa , Antiinflamatorios , Inflamación/terapiaRESUMEN
We investigated the effects of Crotoxin (CTX), the main toxin of South American rattlesnake (Crotalus durissus terrificus) venom, on Walker 256 tumor growth, the pain symptoms associated (hyperalgesia and allodynia), and participation of endogenous lipoxin A4. Treatment with CTX (s.c.), daily, for 5 days reduced tumor growth at the 5th day after injection of Walker 256 carcinoma cells into the plantar surface of adult rat hind paw. This observation was associated with inhibition of new blood vessel formation and decrease in blood vessel diameter. The treatment with CTX raised plasma concentrations of lipoxin A4 and its natural analogue 15-epi-LXA4, an effect mediated by formyl peptide receptors (FPRs). In fact, the treatment with Boc-2, an inhibitor of FPRs, abolished the increase in plasma levels of these mediators triggered by CTX. The blockage of these receptors also abolished the inhibitory action of CTX on tumor growth and blood vessel formation and the decrease in blood vessel diameter. Together, the results herein presented demonstrate that CTX increases plasma concentrations of lipoxin A4 and 15-epi-LXA4, which might inhibit both tumor growth and formation of new vessels via FPRs.
Asunto(s)
Carcinoma 256 de Walker/tratamiento farmacológico , Crotoxina/uso terapéutico , Lipoxinas/metabolismo , Receptores de Formil Péptido/metabolismo , Animales , Antiinflamatorios no Esteroideos/uso terapéutico , Línea Celular Tumoral , Masculino , Ratas , Ratas WistarRESUMEN
Inflammatory bowel diseases (IBD) is the result of dysregulation of mucosal innate and adaptive immune responses. Factors such as genetic, microbial and environmental are involved in the development of these disorders. Accordingly, animal models that mimic human diseases are tools for the understanding the immunological processes of the IBD as well as to evaluate new therapeutic strategies. Crotoxin (CTX) is the main component of Crotalus durissus terrificus snake venom and has an immunomodulatory effect. Thus, we aimed to evaluate the modulatory effect of CTX in a murine model of colitis induced by 2,4,6- trinitrobenzene sulfonic acid (TNBS). The CTX was administered intraperitoneally 18 hours after the TNBS intrarectal instillation in BALB/c mice. The CTX administration resulted in decreased weight loss, disease activity index (DAI), macroscopic tissue damage, histopathological score and myeloperoxidase (MPO) activity analyzed after 4 days of acute TNBS colitis. Furthermore, the levels of TNF-α, IL-1ß and IL-6 were lower in colon tissue homogenates of TNBS-mice that received the CTX when compared with untreated TNBS mice. The analysis of distinct cell populations obtained from the intestinal lamina propria showed that CTX reduced the number of group 3 innate lymphoid cells (ILC3) and Th17 population; CTX decreased IL-17 secretion but did not alter the frequency of CD4+Tbet+ T cells induced by TNBS instillation in mice. In contrast, increased CD4+FoxP3+ cell population as well as secretion of TGF-ß, prostaglandin E2 (PGE2) and lipoxin A4 (LXA4) was observed in TNBS-colitis mice treated with CTX compared with untreated TNBS-colitis mice. In conclusion, the CTX is able to modulate the intestinal acute inflammatory response induced by TNBS, resulting in the improvement of clinical status of the mice. This effect of CTX is complex and involves the suppression of the pro-inflammatory environment elicited by intrarectal instillation of TNBS due to the induction of a local anti-inflammatory profile in mice.
Asunto(s)
Colitis/tratamiento farmacológico , Crotalus , Crotoxina/farmacología , Animales , Colitis/inducido químicamente , Colitis/inmunología , Colitis/metabolismo , Crotoxina/uso terapéutico , Factores de Transcripción Forkhead/metabolismo , Mediadores de Inflamación/metabolismo , Interleucina-17/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Peroxidasa/metabolismo , Células Th17/efectos de los fármacos , Células Th17/inmunología , Células Th17/metabolismo , Ácido Trinitrobencenosulfónico/efectos adversosRESUMEN
A esclerose múltipla é uma doença inflamatória crônica, de origem autoimune, que acarreta diversas alterações motoras, cognitivas e sensitivas. Dentre as alterações sensitivas, a dor é um dos graves problemas que afetam pessoas portadoras desta doença, interferindo com diversos aspectos da vida do paciente. É importante ressaltar que a esclerose múltipla não tem cura, sendo que a terapêutica se concentra nas ações que retardam a progressão da doença e promovem o alívio dos sintomas, melhorando a qualidade da vida do paciente...
Multiple sclerosis is a Central Nervous System Inflamatory demyelinating disease that has as primary symptomps losses of sensory, cognitive and motor functions. Among the sensory alternations, pain is one of the major concern, afecting various aspects of the patients lives...
Asunto(s)
Femenino , Ratones , Crotalus/sangre , Crotoxina/administración & dosificación , Crotoxina/uso terapéutico , Esclerosis Múltiple/inducido químicamente , Venenos de Crotálidos/administración & dosificación , Venenos de Crotálidos/aislamiento & purificación , Venenos de Crotálidos/uso terapéutico , Encefalomielitis , Encefalomielitis Autoinmune Experimental/fisiopatología , Encefalomielitis Autoinmune Experimental/inducido químicamente , Dimensión del DolorRESUMEN
Biomedical research in which venom components are being investigated for their potential as novel therapeutic agents has emerged as an interesting option. Crotapotin, which is purified from the venom of the rattlesnake Crotalus durissus terrificus, has been described as an anti-inflammatory agent that acts on the innate arm of the immune response. Here we have demonstrated that intraperitoneal administration of crotapotin significantly reduces the severity of experimental autoimmune neuritis (EAN), an experimental model for Guillain-Barré syndrome. The reduction of the severity of the disease is associated with a reduction in the mononuclear cells infiltrating the sciatic nerve and a significant decrease in the lymphocyte proliferative response to neuritogenic peptide.
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Antiinflamatorios/uso terapéutico , Crotalus , Crotoxina/uso terapéutico , Neuritis Autoinmune Experimental/prevención & control , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Relación Dosis-Respuesta Inmunológica , Femenino , Síndrome de Guillain-Barré , Inyecciones Intraperitoneales , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/patología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/patología , Activación de Linfocitos , Proteínas de la Mielina/inmunología , Proteínas de la Mielina/farmacología , Neuritis Autoinmune Experimental/inmunología , Neuritis Autoinmune Experimental/patología , Ratas , Ratas Endogámicas Lew , Nervio Ciático/efectos de los fármacos , Nervio Ciático/patología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunologíaRESUMEN
Explora los avatares que acompañaron en Buenos Aires a mediados de la década de 1980 la movilización de enfermos de cáncer interesados en acceder a un tratamiento descalificado por el establishment médico y científico.(AU)
Asunto(s)
Neoplasias/historia , Oncología Médica/historia , Crotoxina/uso terapéutico , Argentina , Neoplasias/terapia , Historia de la MedicinaRESUMEN
A Phase I clinical trial was performed on patients with solid tumors refractory to conventional therapy. Crotoxin was administered i.m. for 30 consecutive days at doses ranging from 0.03 to 0.22 mg/m(2). Patients entered the study after providing a written informed consent. Although 26 patients were entered only 23 were evaluated. Reversible, nonlimiting neuromuscular toxicity evidenced as diplopia because of pareses of the external ocular muscles was present in 13 patients. It started at doses of 0.18 mg/m(2) and lasted from 2 to 6 h. These episodes did not require dose adjustment and disappeared in 1-3 weeks of treatment. Three patients experienced palpebral ptosis, nystagmus (grade 2), and anxiety (grade 2-3) at the dose-limiting toxicity of 0.22 mg/m(2). Also at dose-limiting toxicity, 1 patient showed nystagmus (grade 2) and anxiety (grade 3) without evidence of palpebral ptosis. Transient increases (grades 1-3) in the levels of creatinine kinase, aspartate aminotransferase, and alanine transaminase attributed to crotoxin myotoxicity were observed but returned to normal by the last week of treatment. At 0.21 mg/m(2) there was a case of grade-3 anaphylactic reaction on day 31, which required treatment. Hypersensitivity was regarded as an adverse drug-related reaction, and the patient was removed from the protocol. Two patients at different doses (0.12 mg/m(2) and 0.22 mg/m(2)) had sialorrhea. Four patients had asymptomatic transient increase in blood pressure (up to 20 mm Hg) 12 h after the first injection, which lasted 24 h. No treatment was required and toxicity did not reappear. Six patients experienced slight eosinophilia during the first 2 weeks. The maximum tolerated dose was set at 0.21 mg/m(2). Objective measurable partial responses (>50% reduction of tumor mass) were noted in 2 patients treated at 0.21 mg/m(2) and 1 at 0.12 mg/m(2). One patient (at 0.21 mg/m(2)) presented a complete response on day 110. Crotoxin pharmacokinetics showed rapid absorption from the injection site to blood (t(1/2 A) = 5.2 +/- 0.6 min). Plasma concentration reached a peak (C(max) = 0.79 +/- 0.1 ng/ml) at tau(max) = 19 +/- 3 min. The half-life of the distribution (alpha) phase is 22 +/- 2 min. Starting at 1.5 h after injection, the decrease in plasma concentration becomes slower, reaching 14 +/- 3 pg/ml 24 h after injection. The profile is dominated by the elimination (beta) phase with a half-life of 5.2 +/- 0.6 h. Consequently, 24 h after the injection ( approximately 5 half-life) 97% of the product was eliminated. The area under plasma concentration versus time curve was 0.19 +/- 0.05 microg/min/ml. Assuming availability (F) approximately 1, the clearance is C(L) = 26.3 +/- 7 ml/min, and the apparent volume of distribution is V(d) = 12 +/- 3 liter/kg. The recommended dose for a Phase II study is 0.18 mg/m(2).
Asunto(s)
Crotoxina/farmacocinética , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Alanina Transaminasa/sangre , Alanina Transaminasa/efectos de los fármacos , Área Bajo la Curva , Creatina Quinasa/sangre , Creatina Quinasa/efectos de los fármacos , Crotoxina/efectos adversos , Crotoxina/uso terapéutico , Diarrea/inducido químicamente , Diplopía/inducido químicamente , Relación Dosis-Respuesta a Droga , Eosinofilia/inducido químicamente , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/metabolismo , Dolor/etiología , Dolor/prevención & control , Transaminasas/sangre , Transaminasas/efectos de los fármacos , Resultado del TratamientoRESUMEN
A phase I study was performed to evaluate the maximum tolerated dose (MTD), safety profile and pharmacokinetic data with VRCTC-310, a natural product derived from purified snake venom fractions, with phospholipase A2 activity and inhibitory effects against human and murine tumor cell lines. Fifteen patients with refractory malignancies were entered after providing written informed consent. VRCTC-310 was administered as an intramuscular injection daily for 30 consecutive days. Doses were escalated from 0.0025 to 0.023 mg/kg. Toxicities included local pain at the injection site, eosinophilia, reversible diplopia and palpebral ptosis. Dose escalation was stopped at 0.023 mg/kg, when two patients had developed anaphylactoid reactions. Both cases had high VRCTC-310-specific IgG by EIA. MTD was 0.017 mg/kg and the recommended dose for phase II studies is 0.017 mg/kg. Stabilization was found in six patients.
Asunto(s)
Antineoplásicos/uso terapéutico , Proteínas Cardiotóxicas de Elápidos/uso terapéutico , Crotoxina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Fosfolipasas A/antagonistas & inhibidores , Venenos de Serpiente/química , Adulto , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Área Bajo la Curva , Proteínas Cardiotóxicas de Elápidos/efectos adversos , Proteínas Cardiotóxicas de Elápidos/farmacocinética , Crotoxina/efectos adversos , Crotoxina/farmacocinética , Combinación de Medicamentos , Resistencia a Antineoplásicos , Femenino , Semivida , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Fosfolipasas A2RESUMEN
1. The effect of purified crotapotin, a non-toxic non-enzymatic chaperon protein normally complexed to a phospholipase A2 (PLA2) in South America rattlesnake venom, was studied in the acute inflammatory response induced by carrageenin (1 mg/paw), compound 48/80 (3 micrograms/paw) and 5-hydroxytryptamine (5-HT) (3 micrograms/paw) in the rat hind-paw. The effects of crotapotin on platelet aggregation, mast cell degranulation and eicosanoid release from guinea-pig isolated lung were also investigated. 2. Subplantar co-injection of crotapotin (1 and 10 micrograms/paw) with carrageenin or injection of crotapotin (10 micrograms/paw) into the contralateral paw significantly inhibited the carrageenin-induced oedema. This inhibition was also observed when crotapotin (10-30 micrograms/paw) was administered either intraperitoneally or orally. Subplantar injection of heated crotapotin (15 min at 60 degrees C) failed to inhibit carrageenin-induced oedema. Subplantar injection of crotapotin (10 micrograms/paw) also significantly inhibited the rat paw oedema induced by compound 48/80, but it did not affect 5-HT-induced oedema. 3. In adrenalectomized animals, subplantar injection of crotapotin markedly inhibited the oedema induced by carrageenin. The inhibitory effect of crotapotin was also observed in rats depleted of histamine and 5-HT stores. 4. Crotapotin (30 micrograms/paw) had no effect on either the histamine release induced by compound 48/80 in vitro or on the platelet aggregation induced by both arachidonic acid (1 nM) and platelet activating factor (1 microM) in human platelet-rich plasma. The platelet aggregation and thromboxane B2 (TXB2) release induced by thrombin (100 mu ml-1) in washed human platelets were also not affected by crotapotin. In addition, crotapotin (10 microg/paw) did not affect the release of 6-oxo-prostaglandin Fla, and TXB2 induced by ovalbumin in sensitized guinea-pig isolated lungs.5. Our results indicate that the anti-inflammatory activity of crotapotin is not due to endogenous corticosteroid release or inhibition of cyclo-oxygenase activity. It is possible that crotapotin may interact with extracellular PLA2 generated during the inflammatory process thereby reducing its hydrolytic activity.
Asunto(s)
Crotoxina/uso terapéutico , Edema/tratamiento farmacológico , Fosfolipasas A/metabolismo , 6-Cetoprostaglandina F1 alfa/metabolismo , Administración Oral , Animales , Ácido Araquidónico/farmacología , Carragenina/administración & dosificación , Carragenina/toxicidad , Degranulación de la Célula/efectos de los fármacos , Crotoxina/administración & dosificación , Crotoxina/farmacología , Modelos Animales de Enfermedad , Edema/inducido químicamente , Cobayas , Liberación de Histamina/efectos de los fármacos , Humanos , Inyecciones Intraperitoneales , Masculino , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Fosfolipasas A2 , Factor de Activación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Ratas , Ratas Wistar , Serotonina/administración & dosificación , Serotonina/toxicidad , Tromboxano B2/metabolismo , p-Metoxi-N-metilfenetilamina/administración & dosificación , p-Metoxi-N-metilfenetilamina/toxicidadRESUMEN
Myonecrosis is one of the effects of Bothrops jararacussu venom, from which a myotoxin was isolated showing structural homology to phospholipase A2 (PLA2), but without enzymatic activity. Such myotoxic activity is also present in the Crotalus durissus terrifucus venom, and is attributed to crotoxin and to PLA2 (crotoxin B), the basic component of the crotoxin complex. The Bothrops jararacussu venom showed three proteins with immunologic identity to PLA2 from crotoxin. The bothropic (AB) and the bothropic/crotalic (AB/C) anti-venoms, two commercial polyvalent anti-venoms produced at Instituto Butantan, were compared in order to assess their capacity for neutralization of the lethal, hemorrhagic, coagulant and myotoxic activities of Bothrops jararacussu venom. Both anti-venoms showed the same level of hemorrhagic activity neutralization. However, AB/C was about three times more efficient than AB in neutralizing the myotoxic activity, and two times more potent for neutralization of lethality and coagulant activity of Bothrops jararacussu venom. These data suggest that the use of AB/C could be of value in the treatment of patients bitten by snakes of this species.