Evaluation of toxicity after one-months treatment with Bauhinia forficata decoction in streptozotocin-induced diabetic rats

Abstract Background Previous experiments have shown that a decoction of Bauhinia forficata leaves reduces the changes in carbohydrate and protein metabolism that occur in rats with streptozotocin-induced diabetes. In the present investigation, the serum activities of enzymes known to be reliable toxicity markers were monitored in normal and streptozotocin-diabetic rats to discover whether the use of B. forficata decoction has toxic effects on liver, muscle or pancreas tissue or on renal microcirculation. Methods An experimental group of normal and streptozotocin-diabetic rats received an aqueous decoction of fresh B. forficata leaves (150 g/L) by mouth for 33 days while a control group of normal and diabetic rats received water for the same length of time. The serum activity of the toxicity markers lactate dehydrogenase, creatine kinase, amylase, angiotensin-converting enzyme and bilirubin were assayed before receiving B. forficata decoction and on day 19 and 33 of treatment. Results The toxicity markers in normal and diabetic rats were not altered by the diabetes itself nor by treatment with decoction. Whether or not they received B. forficata decoction the normal rats showed a significant increase in serum amylase activity during the experimental period while there was a tendency for the diabetic rats, both treated and untreated with decoction, to have lower serum amylase activities than the normal rats. Conclusions Administration of an aqueous decoction of B. forficata is a potential treatment for diabetes and does not produce toxic effects measurable with the enzyme markers used in our study.

We thank FAPESP, FUNDUNESP and PADC-FCF (UNESP, Araraquara) for financial support. We are also grateful to the technicians TN Nunes and FA Iagame for their help and to Dr. GD Zanetti, Industrial Pharmacy Department Herbarium, Federal University of Santa Maria, Rio Grande do Sul, Brazil, for identification and authentication of Bauhinia forficata.

We thank FAPESP, FUNDUNESP and PADCFCF (UNESP, Araraquara) for financial support. We are also grateful to the technicians TN Nunes and FA Iagame for their help and to Dr. GD Zanetti, Industrial Pharmacy Department Herbarium, Federal University of Santa Maria, Rio Grande do Sul, Brazil, for identification and authentication of Bauhinia forficata.