变黑白头翁提取物降低亚砷酸盐对小鼠精细胞的毒性

目的：研究变黑白头翁提取物降低亚砷酸盐对小鼠精细胞毒性的作用。方法：给予实验小鼠亚砷酸钠（20mg／kg每日），并分别在第30、60、90天对小鼠进行检测。亚砷酸盐中毒小鼠被分为2组，其中一组给予变黑白头翁提取物（35mg／kg），另一组给予85％乙醇。通过检测小鼠精细胞凋亡标志蛋白CYP1A1、p53及caspase3的活性，确定细胞及DNA的损伤情况，并测定睾丸毒性标志物的水平。通过圆二色光谱仪及熔化温度数据检测变黑白头翁提取物与DNA的相互作用情况。结果：亚砷酸盐中毒小鼠的所有细胞凋亡标志蛋白及睾丸毒性标志物的水平均有所上升，而经变黑白头翁提取物治疗的小鼠上述各项指标均降低或恢复至正常水平。变黑白头翁提取物与DNA相互作用，引起了DNA结构和构象的变化。结论：变黑白头翁提取物可作为砷中毒引起的生殖功能损害的治疗药物给予研究和开发。

Dihydroxy-isosteviol methyl ester of Pulsatilla nigricans extract reduces arsenic-induced DNA damage in testis cells of male mice: its toxicity, drug-DNA interaction and signaling cascades

OBJECTIVE： To evaluate the ameliorative efficacy of dihydroxy-isosteviol methyl ester （DIME） of Pulsatilla nigdcans extract in arsenic-induced DNA damage in testis ceils of mice. METHODS： The mice were treated with sodium arsenite （SA） solution intragastrically at a dose of 20 mg/kg per day and examined at 30, 60, and 90 d after treatment. We divided SA- intoxicated mice into two sub-groups： one fed with DIME at a dose of 35 mg/kg and the other with 85% alcohol. We analyzed the expressions of apoptotic signal proteins like CYPIAI, p53 and caspase 3, ascertained the level of cellular and DNA damage and estimated the level of testicular-toxicity biomarkers. We studied the interaction of DIME with calf thymus DNA as target through circular dichroism spectra and melting temperature profiles. RESULTS： We observed an elevation in all apoptotic and toxicity biomarkers leading to cellular and DNA damage in the SA-intoxicated mice which showed significant inhibition or reversal on administration of DIME. Results also showed that DIME interacted with DNA, bringing in discernible changes in structure and conformation. CONCLUSION： DIME has potentials for therapeutic use in amelioration of arsenic-induced reproductive toxicity.