甘草甜素调节U14宫颈癌小鼠免疫功能及诱导凋亡的作用

为探讨甘草甜素调节U14 宫颈癌小鼠免疫功能及诱导凋亡作用，将U14宫颈癌小鼠随机分为模型组、甘草甜素低、中、高剂量组（25、50、100 mg/kg）及环磷酰胺组（25 mg/kg），另设正常组，每组10只；灌胃给药，1次/d，共21 d。测量各组小鼠瘤体积（最大直径）、瘤质量，计算胸腺指数、脾脏指数，TUNEL法检测细胞凋亡指数，实时定量PCR法检测Caspase-3、Bax及Bcl-2 mRNA表达，Western Blot法检测p-PI3K、p-AKT蛋白表达等指标。结果发现，与模型组比较，甘草甜素低、中、高剂量组小鼠瘤体积（最大直径）及瘤质量显著降低（P<0.05或P<0.01），抑瘤率分别为15.68%、25.41%和38.38%；与模型组比较，甘草甜素低、中、高剂量组小鼠胸腺指数、脾脏指数、IL-2、IFN-γ、TNF-α含量、凋亡指数、Caspase-3及Bax mRNA表达显著增加（P<0.05或P<0.01），而Bcl-2 mRNA及p-PI3K、p-AKT蛋白表达显著降低（P<0.05或P<0.01）。上述结果表明，甘草甜素具有抑制U14宫颈癌小鼠肿瘤生长的作用，该作用与改善免疫功能及诱导凋亡作用有关。

Effect of Glycyrrhizin on Immune Function and Apoptosis of U14 Cervical Cancer Mice

To investigate the effect of glycyrrhizin on regulating immune function and inducing apoptosis in U14 cervical cancer mice, U14 cervical cancer mice were randomly divided into model group, low-dose, medium-dose and high-dose glycyrrhizin groups (25, 50 and 100 mg/kg), cyclophosphamide group (25 mg·kg?1) and normal group with 10 mice in each group. Intragastric administration was performed once a day for 21 days. Tumor volume (maximum diameter) and tumor mass were measured, thymus index and spleen index were calculated, apoptosis index was detected by TUNEL assay, mRNA expressions of Caspase-3, Bax and Bcl-2 were detected by real-time quantitative PCR, and protein expressions of p-PI3K and p-Akt were detected by Western Blot. The results showed that the tumor volume (maximum diameter) and tumor weight in low-dose, medium-dose and high-dose glycyrrhizin groups were significantly lower than those in the model group (P<0.05 or P<0.01) after 21 days of administration, and the tumor inhibition rates were 15.68%, 25.41% and 38.38%, respectively. Compared with the model group, thymus index, spleen index, IL-2, IFN-γ, TNF-α contents, apoptosis index, Caspase-3 and Bax mRNA expressions in low-dose, medium-dose and high-dose glycyrrhizin groups were increased (P<0.05 or P<0.01), while Bcl-2 mRNA and p-PI3K and p-AKT protein expressions were decreased (P<0.05 or P<0.01). The above results indicate that glycyrrhizin can inhibit tumor growth in U14 cervical cancer mice, which is related to improving immune function and inducing apoptosis.