Immunotoxicity of Panax notoginseng in Sprague-Dawley rats

  Objective  To observe the immune toxicity of Panax notoginseng (Pn) and to provide a basis for safety assessment of Pn.

  Methods  We collected Pn samples in Wenshan of Yunnan province and triturated them into powder and screened with a 120 mesh sieve before experiment. Fourty male Sprague-Dawley (SD) rats were randomly divided into four groups (10 in each group): a control group and low, moderate, and high Pn groups treated with gastric gavage of Pn at doses of 0.750, 2.372, and 7.500 g/kg body weight once a day continuously for 90 days. All the rats were observed for general conditions and their body weight and feed intakes were recorded periodically and hematologic and biochemical indicators were detected and pathological changes in spleen and thymus tissues were observed at the end of experiment. The immunologic function of the rats was assessed with tests of serum hemolysin, natural killer (NK) cell activity, lymphocyte transformation, and peripheral blood lymphocyte activation.

  Results  No abnormalities in physical signs and behaviors were observed among all the rats. Compared to those of the control rats, no significant differences were detected for the rats of three Pn groups in body weight, white blood cell count, white blood cell differential count, total serum protein, serum albumin, alanine aminotransferase, aspartate aminotransferase, 50% hemolysin value, NK cell activity, lymphocyte transformation, and weight and organ coefficients of spleen and thymus. There were also no obvious pathological changes in spleen and thymus tissues in the rats of Pn groups. For rats of low, moderate and high Pn groups, the expression of CD161α⁺CD25⁺ in NK cells (10.17 ± 5.20, 7.25 ± 3.22 and 8.63 ± 1.90), CD45RA⁺CD25⁺ in B lymphocytes (9.64 ± 4.83, 7.76 ± 3.18 and 9.06 ± 2.85), and CD3⁺CD25⁺ in T lymphocytes (17.08 ± 4.62, 14.11 ± 2.87 and 14.27 ± 3.31) were not significantly different from those for the rats of control group.

  Conclusion  The experiment results demonstrate no immunotoxicity of Panax notoginseng in SD rats.