Subchronic toxicity study of the total flavonoids from Rosa laevigata Michx fruit in rats.

The total flavonoids (TFs) from Rosa laevigata Michx fruit showed hepatoprotective and antioxidant activities. However, the safety of this natural product has not been investigated. In the present paper, a 90-day subchronic toxicity study was conducted, and the tested TFs was orally administered to rats at the doses of 500, 1000 and 2000mg/kg/day. The toxicity of the TFs was evaluated on base of ophthalmic examination, body weight, feed/water consumption, urinalysis, hematology, clinical biochemistry and pathology. No toxic signs of the TFs at the doses of 500 and 1000mg/kg/day were observed. However, decreased PLT was found in the 2000mg/kg/day groups and increased intercellular space of myocardial cells was observed in the male 2000mg/kg/day group compared with control. A significant increase in the relative cardiac weight was observed in the male 1000 and 2000mg/kg/day groups. And the significant decrease in the absolute and relative weight of adrenals in the female 1000 and 2000mg/kg groups was happened. The TFs could cause mild side effects at the dose of 1000mg/kg/day in males and females. Thus, the dose of 500mg/kg/day for male and female were selected as the no-observed-adverse-effect level (NOAEL). The present study provides useful data for subsequent researches and new drug exploration of the TFs from R. laevigata Michx fruit.