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1.
Int. j. cardiovasc. sci. (Impr.) ; 37: e20220075, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534621

RESUMO

Abstract Hemostasis is a complex set of biological processes responsible for blood fluidity within normal vessels and for the physiological interruption of bleeding in cases of vascular injury. Bothrops moojeni snake venom is rich in bioactive compounds of pharmacological and clinical interest since its protein components are capable of interfering with many points of the hemostatic process. Here, we present the B. moojeni venom proteins that affect hemostasis and discuss their pharmacological and clinical potential. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Data were obtained from the CAPES Journal Portal database, using the terms "Bothrops" AND "hemostasis", in a search for scientific articles made available in the last 20 years. Many components isolated from B. moojeni snake venom are characterized for their effect on hemostasis and possible application in the diagnosis and treatment of hemostatic disorders.

2.
Toxicol In Vitro ; 88: 105562, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36690282

RESUMO

Dengue fever is considered a major public health problem in tropical and subtropical regions. Our study analyzed the effect of BaltPLA2, a phospholipase A2 from Bothrops alternatus snake venom, on the viability of cells infected with Dengue virus. In presence of BaltPLA2, the viability of infected cells increased significantly in virucidal, post-treatment, and adsorption assays. Although preliminary these results reveal the need for further studies to investigated whether BaltPLA2 has antiviral activity against Dengue virus.


Assuntos
Bothrops , Venenos de Crotalídeos , Vírus da Dengue , Animais , Fosfolipases A2/farmacologia , Venenos de Serpentes , Antivirais/farmacologia , Venenos de Crotalídeos/farmacologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-33915386

RESUMO

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.

4.
Int J Exp Pathol ; 99(5): 226-235, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30456925

RESUMO

Ophidic accidents are among the problems of public health in Brazil. The components from bothropic venom are responsible for many systemic clinical complications resulting from envenomation. The present work aimed to analyse the systemic changes induced in mice after intraperitoneal administration of BmooTX-I, a myotoxic acidic phospholipase A2 isolated from Bothrops moojeni venom. Urinalysis was performed and the following plasma biochemical markers were documented: urea, creatinine and uric acid (renal function); glucose and amylase (pancreatic function); alanine aminotransferase, alkaline phosphatase and gamma-GT (intra- and extrahepatic function); creatine kinase and enzymatic lactate (muscle function). Our results showed that after the intraperitoneal injection of BmooTX-I the urine of these animals showed glycosuria, proteinuria, haematuria, bacteriuria, bilirubinuria, polyuria and nitrite. The plasma biochemical analysis showed alterations in levels of urea, creatinine and uric acid. Amylase concentration was not altered significantly, but the plasma glucose increased significantly compared to controls. The plasma levels of alanine aminotransferase and alkaline phosphatase decreased and increased, respectively, in these same animals. On the other hand, the plasma γGT concentration did not undergo significant modification compared to the control group. The plasma concentration of CK increased, while the enzymatic lactate concentration decreased after the injection of the BmooTX-I. Therefore, in mice BmooTX-I is capable of causing systemic alterations which manifest as renal, muscular, hepatic and pancreatic impairment.


Assuntos
Bothrops , Venenos de Crotalídeos/enzimologia , Fosfolipases A2/toxicidade , Animais , Biomarcadores/sangue , Biomarcadores/urina , Creatina Quinase/sangue , Venenos de Crotalídeos/química , Venenos de Crotalídeos/toxicidade , Injeções Intraperitoneais , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Músculo Esquelético/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Fosfolipases A2/isolamento & purificação
5.
Protein Pept Lett ; 25(10): 943-952, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30289061

RESUMO

BACKGROUND: In last decades, snake venoms have aroused great interest of the medicine due to the pathophysiological effects caused by their toxins. These include the phospholipases A2, low molecular weight proteins capable of causing haemorrhagic, myotoxic, inflammatory and neurotoxic effects after an ophidian accident. The present work describes the isolation and biochemical characterization of a new PLA2 isolated from the B. alternatus snake venom, which was named BaltPLA2. METHOD: The rapid and efficient purification of this toxin was performed using only two chromatography steps (anion exchange and hydrophobic chromatography). RESULTS: BaltPLA2 is an acidic protein (pI 4.4) with an apparent molecular mass of 17000 (SDSPAGE) and 14074.74 Da (MALDI TOF/TOF). Analysis of fragments ion by MS / MS showed the following internal amino acid sequence SGVIICGEGTPCEK, which did not exhibit homology with other PLA2 from the same venom. BaltPLA2 is a catalytically active, which displayed an anticoagulant action, inhibition of platelet aggregation induced by epinephrine (~ 80%) and ADP (24%). BaltPLA2 also was able to induce myonecrosis and the release of cytokines (IL-10, IL-12 and TNF- α) in macrophages culture. CONCLUSION: The results presented in this work greatly contribute to a better understanding of the mechanism of enzymatic and pharmacological actions of PLA2s from snake venoms and they may contribute to its application in medical research.


Assuntos
Bothrops , Fosfolipases A2/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Venenos de Serpentes/enzimologia , Sequência de Aminoácidos , Animais , Humanos , Fosfolipases A2/química
6.
Biomed Res Int ; 2017: 4315832, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29226136

RESUMO

This work reports the purification and functional characterization of BmooPAi, a platelet-aggregation-inhibiting factor from Bothrops moojeni snake venom. The toxin was purified by a combination of three chromatographic steps (ion-exchange on DEAE-Sephacel, molecular exclusion on Sephadex G-75, and affinity chromatography on HiTrap™ Heparin HP). BmooPAi was found to be a single-chain protein with an apparent molecular mass of 32 kDa on 14% SDS-PAGE, under reducing conditions. Sequencing of BmooPAi by Edman degradation revealed the amino acid sequence LGPDIVPPNELLEVM. The toxin was devoid of proteolytic, haemorrhagic, defibrinating, or coagulant activities and induced no significant oedema or hyperalgesia. BmooPAi showed a rather specific inhibitory effect on ristocetin-induced platelet aggregation in human platelet-rich plasma, whereas it had little or no effect on platelet aggregation induced by collagen and adenosine diphosphate. The results presented in this work suggest that BmooPAi is a toxin comprised of disintegrin-like and cysteine-rich domains, originating from autolysis/proteolysis of PIII SVMPs from B. moojeni snake venom. This toxin may be of medical interest because it is a platelet aggregation inhibitor, which could potentially be developed as a novel therapeutic agent to prevent and/or treat patients with thrombotic disorders.


Assuntos
Bothrops/metabolismo , Fator de Ativação de Plaquetas/isolamento & purificação , Fator de Ativação de Plaquetas/farmacologia , Inibidores da Agregação Plaquetária/isolamento & purificação , Inibidores da Agregação Plaquetária/farmacologia , Venenos de Serpentes/metabolismo , Difosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Plaquetas/efeitos dos fármacos , Hemorragia/tratamento farmacológico , Humanos , Masculino , Camundongos , Peso Molecular , Agregação Plaquetária/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Ratos , Ratos Wistar
7.
Artigo em Inglês | MEDLINE | ID: mdl-28775739

RESUMO

BACKGROUND: Snake venoms are a complex mixture of proteins, organic and inorganic compounds. Some of these proteins, enzymatic or non-enzymatic ones, are able to interact with platelet receptors, causing hemostatic disorders. The possible therapeutic potential of toxins with antiplatelet properties may arouse interest in the pharmacological areas. The present study aimed to purify and characterize an antiplatelet DC protein from Bothrops alternatus snake venom. METHODS: The protein, called BaltDC (DC protein from B. alternatus snake venom), was purified by a combination of ion-exchange chromatography on DEAE-Sephacel column and gel filtration on Sephadex G-75. The molecular mass was estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). The amino acid sequence of the N-terminal region was carried out by Edman degradation method. Platelet aggregation assays were performed in human platelet-rich plasma (PRP). Infrared (IR) spectroscopy was used in order to elucidate the interactions between BaltDC and platelet membrane. RESULTS: BaltDC ran as a single protein band on SDS-PAGE and showed apparent molecular mass of 32 kDa under reducing or non-reducing conditions. The N-terminal region of the purified protein revealed the amino acid sequence IISPPVCGNELLEVGEECDCGTPENCQNECCDA, which showed identity with other snake venom metalloproteinases (SVMPs). BaltDC was devoid of proteolytic, hemorrhagic, defibrinating or coagulant activities, but it showed a specific inhibitory effect on platelet aggregation induced by ristocetin and epinephrine in PRP. IR analysis spectra strongly suggests that PO32- groups, present in BaltDC, form hydrogen bonds with the PO2- groups present in the non-lipid portion of the membrane platelets. CONCLUSIONS: BaltDC may be of medical interest since it was able to inhibit platelet aggregation.

8.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1484726

RESUMO

Abstract Background: Snake venoms are a complex mixture of proteins, organic and inorganic compounds. Some of these proteins, enzymatic or non-enzymatic ones, are able to interact with platelet receptors, causing hemostatic disorders. The possible therapeutic potential of toxins with antiplatelet properties may arouse interest in the pharmacological areas. The present study aimed to purify and characterize an antiplatelet DC protein from Bothrops alternatus snake venom. Methods: The protein, called BaltDC (DC protein from B. alternatus snake venom), was purified by a combination of ion-exchange chromatography on DEAE-Sephacel column and gel filtration on Sephadex G-75. The molecular mass was estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). The amino acid sequence of the N-terminal region was carried out by Edman degradation method. Platelet aggregation assays were performed in human platelet-rich plasma (PRP). Infrared (IR) spectroscopy was used in order to elucidate the interactions between BaltDC and platelet membrane. Results: BaltDC ran as a single protein band on SDS-PAGE and showed apparent molecular mass of 32 kDa under reducing or non-reducing conditions. The N-terminal region of the purified protein revealed the amino acid sequence IISPPVCGNELLEVGEECDCGTPENCQNECCDA, which showed identity with other snake venom metalloproteinases (SVMPs). BaltDC was devoid of proteolytic, hemorrhagic, defibrinating or coagulant activities, but it showed a specific inhibitory effect on platelet aggregation induced by ristocetin and epinephrine in PRP. IR analysis spectra strongly suggests that PO 3 2 groups, present in BaltDC, form hydrogen bonds with the PO 2 groups present in the non-lipid portion of the membrane platelets. Conclusions: BaltDC may be of medical interest since it was able to inhibit platelet aggregation.

9.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954849

RESUMO

Background: Snake venoms are a complex mixture of proteins, organic and inorganic compounds. Some of these proteins, enzymatic or non-enzymatic ones, are able to interact with platelet receptors, causing hemostatic disorders. The possible therapeutic potential of toxins with antiplatelet properties may arouse interest in the pharmacological areas. The present study aimed to purify and characterize an antiplatelet DC protein from Bothrops alternatus snake venom. Methods: The protein, called BaltDC (DC protein from B. alternatus snake venom), was purified by a combination of ion-exchange chromatography on DEAE-Sephacel column and gel filtration on Sephadex G-75. The molecular mass was estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE). The amino acid sequence of the N-terminal region was carried out by Edman degradation method. Platelet aggregation assays were performed in human platelet-rich plasma (PRP). Infrared (IR) spectroscopy was used in order to elucidate the interactions between BaltDC and platelet membrane. Results: BaltDC ran as a single protein band on SDS-PAGE and showed apparent molecular mass of 32 kDa under reducing or non-reducing conditions. The N-terminal region of the purified protein revealed the amino acid sequence IISPPVCGNELLEVGEECDCGTPENCQNECCDA, which showed identity with other snake venom metalloproteinases (SVMPs). BaltDC was devoid of proteolytic, hemorrhagic, defibrinating or coagulant activities, but it showed a specific inhibitory effect on platelet aggregation induced by ristocetin and epinephrine in PRP. IR analysis spectra strongly suggests that PO 3 2 − groups, present in BaltDC, form hydrogen bonds with the PO 2 − groups present in the non-lipid portion of the membrane platelets. Conclusions: BaltDC may be of medical interest since it was able to inhibit platelet aggregation.(AU)


Assuntos
Animais , Venenos de Serpentes , Análise Espectral , Agregação Plaquetária , Bothrops , Transtornos Hemostáticos , Metaloproteases , Dodecilsulfato de Sódio , Eletroforese em Gel de Poliacrilamida
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