Purification and biological activity of the thrombin-like substance isolated from Bothrops insularis venom.
The venom of Bothrops insularis snake, known in Brazil as jararaca ilhoa, contains a variety of proteolytic enzymes such as a thrombin-like substance that is responsible for various pharmacological effects. B. insularis venom chromatography profile showed an elution of seven main fractions. The thrombin-like activity was detected in fractions I and III, the latter being subjected to two other chromatographic procedures, so to say DEAE and Hi Trap Benzamidine. The purity degree of this fraction was confirmed by analytical reverse phase HPLC, which displayed only one main fraction confirmed by SDS-PAGE constituting fraction III. About 5 microg of fraction III protein potentiated the secretion of insulin induced by 2.8 mM of glucose in rats isolated pancreatic beta-cells treated; the increase being around 3-fold higher than its respective control. B. insularis lectin (BiLec; 10 microg/mL) was also studied as to its effect on the renal function of isolated perfused rat kidneys with the use of six Wistar rats. BiLec increased perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF) and glomerular filtration rate (GFR). Sodium (%TNa+) and chloride tubular reabsorption (%TCl-) decreased at 120 min, without alteration in potassium transport. In conclusion, the thrombin-like substance isolated from B. insularis venom induced an increase in insulin secretion, in vitro, and transiently altered vascular, glomerular and tubular parameters in the isolated rat kidney.
Braga
Marcus Davis Machado
MD
Department of Pathology, Federal University of Ceara, Fortaleza, Ceara, Brazil.
Martins
Alice Maria Costa
AM
de Menezes
Dalgimar Bezerra
DB
Barbosa
Paulo Sergio Ferreira
PS
Evangelista
Janaina Serra Azul Monteiro
JS
Toyama
Marcos Hikari
MH
Toyama
Daniela Oliveira
DO
Fonteles
Manassés Claudino
MC
Monteiro
Helena Serra Azul
HS
D000818:Animals; D001777:Blood Coagulation / Q000187:drug effects*; D017837:Bothrops; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003435:Crotalid Venoms / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006490:Hemostatics / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D007668:Kidney / Q000098:blood supply / Q000187:drug effects / Q000473:pathology; D007684:Kidney Tubules / Q000187:drug effects / Q000378:metabolism; D037102:Lectins / Q000494:pharmacology; D008297:Male; D010477:Perfusion; D051381:Rats; D017208:Rats, Wistar; D014554:Urination / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D002712:Chlorides; D003435:Crotalid Venoms; D006490:Hemostatics; D007328:Insulin; D037102:Lectins