title: Bothrops leucurus venom induces nephrotoxicity in the isolated perfused kidney and cultured renal tubular epithelia.
abstract: Bites from snake (Bothrops genus) cause local tissue damage and systemic complications, which include alterations such as hemostatic system and acute renal failure (ARF). Recent studies suggest that ARF pathogenesis in snakebite envenomation is multifactorial and involves hemodynamic disturbances, immunologic reactions and direct nephrotoxicity. The aim of the work was to investigate the effects of the Bothrops leucurus venom (BlV) in the renal perfusion system and in cultured renal tubular cells of the type MDCK (Madin-Darby Canine kidney). BlV (10 μg/mL) reduced the perfusion pressure at 90 and 120 min. The renal vascular resistance (RVR) decreased at 120 min of perfusion. The effect on urinary flow (UF) and glomerular filtration rate (GFR) started 30 min after BlV infusion, was transient and returned to normal at 120 min of perfusion. It was also observed a decrease on percentual tubular transport of sodium (%TNa(+)) at 120 min and of chloride (%TCl(-)) at 60 and 90 min. The treatment with BlV caused decrease in cell viability to the lowest concentration tested with an IC(50) of 1.25 μg/mL. Flow cytometry with annexin V and propidium iodide showed that cell death occurred predominantly by necrosis. However, a cell death process may involve apoptosis in lower concentrations. BlV treatment (1.25 μg/mL) led to significant depolarization of the mitochondrial membrane potential and, indeed, we found an increase in the expression of cell death genes in the lower concentrations tested. The venom also evoked an increase in the cytosolic Ca(2+) in a concentration dependent manner, indicating that Ca(2+) may participate in the venom of B. leucurus effect. The characterization of the effects in the isolated kidney and renal tubular cells gives strong evidences that the acute renal failure induced by this venom is a result of the direct nephrotoxicity which may involve the cell death mechanism.
authors.affiliation: Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, Fortaleza, Ceará, Brazil.
authors.forename: Isabel Cristina Oliveira
authors.initials: IC
authors.lastname: de Morais
authors.forename: Alba Fabíola Costa
authors.initials: AF
authors.lastname: Torres
authors.forename: Gustavo José da Silva
authors.initials: GJ
authors.lastname: Pereira
authors.forename: Ticiana Praciano
authors.initials: TP
authors.lastname: Pereira
authors.forename: Ramon Róseo de Paula
authors.initials: RR
authors.lastname: Pessoa Bezerra de Menezes
authors.forename: Clarissa Perdigão
authors.initials: CP
authors.lastname: Mello
authors.forename: Antonio Rafael
authors.initials: AR
authors.lastname: Coelho Jorge
authors.forename: Alexandre Havt
authors.initials: AH
authors.lastname: Bindá
authors.forename: Marcos Hikari
authors.initials: MH
authors.lastname: Toyama
authors.forename: Helena Serra Azul
authors.initials: HS
authors.lastname: Monteiro
authors.forename: Soraya Soubhi
authors.initials: SS
authors.lastname: Smaili
authors.forename: Alice Maria Costa
authors.initials: AM
authors.lastname: Martins
mesh_terms: D000818:Animals; D017304:Annexin A5; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis / Q000235:genetics; D017837:Bothrops; D002118:Calcium / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004396:Coloring Agents; D003435:Crotalid Venoms / Q000633:toxicity*; D004285:Dogs; D004847:Epithelial Cells / Q000187:drug effects / Q000473:pathology; D004848:Epithelium / Q000187:drug effects / Q000473:pathology*; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D015870:Gene Expression / Q000187:drug effects; D007674:Kidney Diseases / Q000139:chemically induced* / Q000473:pathology*; D007684:Kidney Tubules / Q000187:drug effects / Q000473:pathology*; D008297:Male; D009924:Organ Culture Techniques; D011419:Propidium; D051381:Rats
chemical_list: D017304:Annexin A5; D051017:Apoptosis Regulatory Proteins; D004396:Coloring Agents; D003435:Crotalid Venoms; D005456:Fluorescent Dyes; D011419:Propidium; D016650:Fluorescein-5-isothiocyanate; D002118:Calcium