Safety Evaluation of an Apitherapy Formulation, Bao-Yuan-Ling: Acute and Sub-acute Oral Toxicity in Wistar Rats

Bao-Yuan-Ling (BYL) is an apitherapy formulation which is composed of royal jelly, propolis and bee venom. Cardioprotective effects of BYL has been demonstrated, while the toxicity of BYL was not clear. In this study, acute and sub-acute toxicity test of BYL was processed following Organization for Economic Co-operation and Development (OECD) 423 and OECD 407, respectively, in Wistar rats. In acute toxicity test, rats were orally treated with BYL at the single dose of 2000 mg/kg and 5000 mg/kg. No death occurred in the acute toxicity test for 7 days, which indicated the lethal dose 50% value exceeded 5000 mg/kg. In sub-acute toxicity study, rats were treated with BYL at the dose of 250 mg/kg, 500 mg/kg and 1000 mg/kg in a daily base for continuous 28 days. Results showed that female rats were more likely to be affected by BYL in body weight changes, while biochemical indicators of blood serum in male rats were more susceptible to drug effects. However, neither female nor male rats were affected by BYL administration significantly on the organs via hematoxylin-eosin staining analysis. Results suggested that BYL was slightly toxic and clinical use was safe and reliable.