The role of oxidative stress in streptozotocin-induced diabetic nephropathy in rats.
OBJECTIVE
The objective of this study was to evaluate the role of oxidative stress in an experimental model of streptozotocin-induced diabetic nephropathy in rats.


METHODS
Wistar, adult, male rats were used in the study. Animals were divided in the following groups: Citrate (control, citrate buffer 0.01M, pH 4.2 was administrated intravenously - i.v - in the caudal vein), Uninephrectomy+Citrate (left uninephrectomy-20 days before the study), DM (streptozotocin, 65 mg/kg, i.v, on the 20th day of the study), Uninephrectomy+DM. Physiological parameters (water and food intake, body weight, blood glucose, kidney weight, and relative kidney weight); renal function (creatinine clearance), urine albumin (immunodiffusion method); oxidative metabolites (urinary peroxides, thiobarbituric acid reactive substances, and thiols in renal tissue), and kidney histology were evaluated.


RESULTS
Polyphagia, polydipsia, hyperglycemia, and reduced body weight were observed in diabetic rats. Renal function was reduced in diabetic groups (creatinine clearance, p < 0.05). Uninephrectomy potentiated urine albumin and increased kidney weight and relative kidney weight in diabetic animals (p < 0.05). Urinary peroxides and thiobarbituric acid reactive substances were increased, and the reduction in thiol levels demonstrated endogenous substrate consumption in diabetic groups (p < 0.05). The histological analysis revealed moderate lesions of diabetic nephropathy.


CONCLUSIONS
This study confirms lipid peroxidation and intense consumption of the antioxidant defense system in diabetic rats. The association of hyperglycemia and uninephrectomy resulted in additional renal injury, demonstrating that the model is adequate for the study of diabetic nephropathy.
Laboratório Experimental de Modelos Animais (LEMA), Escola de Enfermagem da Universidade de São Paulo (EEUSP), São Paulo, SP, Brasil.
Sheila Marques
SM
Fernandes
Laboratório Experimental de Modelos Animais (LEMA), Escola de Enfermagem da Universidade de São Paulo (EEUSP), São Paulo, SP, Brasil.|Colegiado de Enfermagem, Universidade Federal do Amazonas (UFAM), Manaus, AM, Brasil.
Priscilla Mendes
PM
Cordeiro
Laboratório Experimental de Modelos Animais (LEMA), Escola de Enfermagem da Universidade de São Paulo (EEUSP), São Paulo, SP, Brasil.
Mirian
M
Watanabe
Laboratório Experimental de Modelos Animais (LEMA), Escola de Enfermagem da Universidade de São Paulo (EEUSP), São Paulo, SP, Brasil.
Cassiane Dezoti da
CD
Fonseca
Laboratório Experimental de Modelos Animais (LEMA), Escola de Enfermagem da Universidade de São Paulo (EEUSP), São Paulo, SP, Brasil.
Maria de Fatima Fernandes
MF
Vattimo
D000419:Albuminuria / Q000652:urine; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight / Q000502:physiology; D003404:Creatinine / Q000032:analysis; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology; D003928:Diabetic Nephropathies / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D005919:Glomerular Filtration Rate / Q000502:physiology; D007668:Kidney / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D015227:Lipid Peroxidation / Q000502:physiology; D008297:Male; D018384:Oxidative Stress / Q000502:physiology*; D010545:Peroxides / Q000652:urine; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D013311:Streptozocin; D013438:Sulfhydryl Compounds / Q000032:analysis; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D013997:Time Factors
D001786:Blood Glucose; D010545:Peroxides; D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D017392:Thiobarbituric Acid Reactive Substances; D013311:Streptozocin; D003404:Creatinine