Toxicity study of Pueraria mirifica Airy Shaw et Suvatabandhu

Toxicity studies of Pueraria mirifica Airy Shaw et Suvatabandhu root powder were investigated in mice and rats by oral administration of its suspension. Our results showed that P. mirifica produced no signs and symptoms of acute toxicity in mice and LD50 value was greater than 16 g/kg. Subchronic toxicity study in Wistar rats treated orally with P. mirifica suspension at the doses of 10, 100 and 1000 mg/kg.day for 90 consecutive days revealed that the growth rate and food consumption of rats receiving P. mirifica at the doses of 100 and 1000 mg/kg/day were significantly lower than those of the control groups. Hematological results in rats indicated that P. mirifica at the dose of 1000 mg/kg BW/day caused anemia with significant decreases of percent hematocrit, the number of erythrocytes, and hemoglobin but significant increases of percent reticulocyte in both sexes. Two weeks after the cessation of P. mirifica administration, these alterations in male rats returned to normal state whereas in female two of four parameters, percent hematocrit and percent reticulocyte, were found recoverable. In addition, the numbers of white blood cells and platelets in male rats receiving the highest dose were significantly lower than those of the control group but these changes were not observed in female rats of the same dose group. Serum biochemical examination showed that cholesterol levels in male rats receiving P. mirifica at each dose were significantly lower than that of the control group and these changes in female were observed at the doses of 100 and 1000 mg/kg/day. At autopsy the weights of both testis from males rats receiving the highest dose were significantly lower than those of the control group. The uterus of female rats receiving P. mirifica at the doses of 100 and 1000 mg/kg/day looked swelling in appearance and the actual uterine weights and percent relative uterine weights of these two groups were significantly higher than those of the control group. Histopathological examinations indicated that males rats receiving the highest dose of P. mirifica had significantly higher incidence of testicular hyperemia than the control group. Female rats receiving the highest dose of P. mirifica had significantly higher incidence of kidney tubular cast than their control group. Other histopathological changes found in the present study did not correlate with the doses of P. mirifica and hence could not be due to the toxicity of P. mirifica. Taken together, it was found that P. mirifica at the doses of 10 and 100 mg/kg/day given orally in Wistar rats did not cause any abnormalities of hematological or biochemical parameters nor did it cause any dose-related histopathological changes of the visceral organs.