Non-clinical acute and chronic toxicity evaluations of Cissus sicyoides L. (Vitaceae) hydroalcoholic leaf extract

Cissus sicyoides (Cs) has been traditionally used to treat diabetes and belongs to the family Vitaceae, and is known as “vegetable insulin". This study aimed to evaluate the acute and chronic non-clinical toxicity of hydroalcoholic extract from the leaves of Cissus sicyoides (EHA-Cs). The acute test was performed in Wistar rats, administering a single dose of 40.5 mg/kg. Behavioral parameters for pharmacological screening were observed to detect signs of Central Nervous System activity; consumption of daily food and water, and weight evaluation. After day 14, the animals were euthanized and blood samples were collected for laboratory analyses of hematological and biochemical parameters. The chronic tests were administered in doses of 4.5, 13.5 and 40.5 mg/kg. The same parameters were observed together with body temperature, glucose, exploration activity (test on the open field), and motor activity (diagnostic tests on the Rota-rod). For the group given the highest dosage during the study, histopathological examinations of vital organs were performed. For acute toxicity, there were no CNS level effects, changes in water and food consumption, or hematologic parameters. However, there was a significant decrease in weight gain for the treated females. Biochemical analyses of the treated animals presented increased levels of AST (aspartate aminotransferase) in females, uric acid levels in females and males, and amylase in males. In the chronic toxicity tests, water consumption was higher for females (at the dosages of 13.5 and 40.5 mg/kg) and for males (at 40.5 mg/kg). At the dosages of 4.5 and 13.5 mg/kg, feed consumption increased for females, while for males it decreased along with weight gain. Blood analysis presented an increase in albumin and changes in erythrocytes and hemoglobin for males (at the dose of 13.5 mg/kg). Glycemia in females (13.5 mg/kg dose) was significantly less, presenting only slight drops at the other doses. The changes were reversible in the satellite group. EHA-Cs revealed a relatively low toxicity profile (at the popular use dose), and only small changes in hematological and biochemical parameters at the dose of 13.5 mg/kg (3x the popular use dosage). In addition, EHA-Cs did not promote histological changes in vital organs such as the heart, lungs, liver and kidneys.