氟对大鼠免疫细胞增殖及凋亡的影响

摘要

目的 研究不同剂量氟对大鼠免疫细胞增殖能力与凋亡的影响,探讨氟对机体免疫功能的损伤作用.方法 将60只雄性SPF级Wistar大鼠按体重采用随机数字表法分为对照组和低、中、高氟组,每组15只,各组饮水中氟化钠(NaF)剂量分别为0、50、100、150 mg/L,均自由进食普通饲料和水,12周后处死.计算大鼠胸腺免疫器官指数,CCK-8细胞增殖毒性检测试剂盒检测血液中淋巴细胞的增殖活性,Annexin V/PI法检测大鼠血液中单个核细胞的凋亡情况,Tunal法检测脾脏和胸腺淋巴细胞的凋亡情况.结果 染氟12周,大鼠胸腺免疫器官指数组间比较,差异有统计学意义(F=6.50,P＜ 0.05);低、中氟组大鼠胸腺免疫器官指数[(0.70±0.19)、(0.84±0.18)g/kg]与对照组[(1.16±0.33)g/kg]比较显著降低(P均＜0.05).4组间的B、T淋巴细胞活力比较差异有统计学意义(F=539.97、4.92,P均＜0.05);中氟组血液B淋巴细胞活力[(58.09±4.59)％]显著低于对照组和低氟组[(100.00±9.01)％、(106.70±4.82)％,P均＜0.05];低、中氟组血液T淋巴细胞活力[(81.11±2.93)％、(75.68±2.34)％]显着低于对照组[(100.00±34.02)％,P均＜0.05].低、中、高氟组血液单个核细胞凋亡率[(48.00±7.45)％、(47.26±5.94)％、(48.20±3.40)％]明显高于对照组[(32.50±13.70)％,P均＜0.05].光镜下,高氟组脾脏和胸腺中的淋巴细胞凋亡数量明显增多.结论 氟能降低大鼠胸腺免疫器官指数和血液、胸腺及脾脏中淋巴细胞的增殖能力,加快淋巴细胞的凋亡,从而损伤机体的免疫功能.%Objective To study the effects of different fluoride concentrations on proliferation and apoptosis of rats' immune cells,and to explore the effects of fluoride on immune function.Methods Sixty male Wistar rats were randomly divided into four groups,and the concentrations of NaF in drinking water for each group (15 rats in each group) were 0,50,100,and 150 mg/L,respectively.They were freely fed water and commercial standard chow.All rats were sacrificed after 12 weeks.Thymus index was calculated.Lymphocyte proliferation activity in the blood was detected by Cell Counting Kit-8 assay.The apoptosis of monocytes in blood was detected by Annexin V/PI method.The apoptosis of lymphocytes in spleen and thymus was detected by Tunal method.Results After 12 weeks of fluoride exposure,the difference in the thymus immune organ index between the four dose groups was statistically significant (F =6.50,P ＜ 0.05);after 12 weeks,the thymus immune organ index of the low and middle dose groups was significantly lower than that of the control group (0.70 ± 0.19,0.84 ± 0.18 vs 1.16 ± 0.33,P ＜ 0.05).There were significant differences in B and T lymphocyte viability between the four dose groups (F =539.97,4.92,P ＜ 0.05).The viability of B lymphocyte in the blood of the middle dose group was significantly lower than those of control group and the low dose group [(58.09 ± 4.59)％ vs (100.00 ± 9.01)％,(106.70 ± 4.82)％,P ＜ 0.05].The viabilities of T lymphocyte in the blood of the low and middle dose groups were significantly lower than that of the control group [(81.11 ± 2.93)％,(75.68 ± 2.34)％ vs (100.00 ± 34.02)％,P ＜ 0.05].The apoptosis rates of blood mononuclear cells in the fluoride-treated groups were significantly increased than that of control group [(48.00 ± 7.45)％,(47.26± 5.94)％,(48.20 ± 3.40)％ vs (32.50 ± 13.70)％,P ＜ 0.05).Immunohistochemistry results showed that the number of apoptotic lymphocytes in the spleen and thymus increased significantly in high dose group.Conclusion Fluoride can reduce the thymus immune organ index of rats,affect the proliferation of lymphocytes in blood,thymus and spleen,and promote apoptosis of lymphocytes,thus affecting the immune function.