Toll样受体系统在肾脏衰老中的表达变化

Expression changes of Toll-like receptors in aging process of rat kidneys

目的观察Toll样受体(TLRs)系统在肾脏衰老中的表达变化。方法用免疫印迹和实时定量PCR(qRT-PCR)技术分析3月龄组(青年组,n=20)、12月龄组(中年组,n=20)和24月龄组(老年组,n=20)大鼠肾脏中TLRs系统分子、核转录因子(NF-κB)信号通路分子以及炎症因子包括趋化因子配体3(CCL3)、CCL4、CCL5、CD80、肿瘤坏死因子-α(TNF-α)和白细胞介素-12b(IL-12b)的表达变化情况。结果①12月龄组和24月龄组体重[(466.86±32.62)、(617.8±57.34)g]、肾重[(43.25±0.50)、(5.01±1.00)g]、三酰甘油(TG)[(2.32±0.46)、(3.22±0.82)mmol/L]和尿蛋白/肌酐比值[(164.81±38.31)、(256.00±49.39)mg/mmoL]高于3月龄组[(236.3±12.28)g、(1.67±0.68)g、(1.20±0.32)mmol/L、(146.01±22.72)mg/mmoL],差异有统计学意义(P<0.05);24月龄组大鼠血尿素氮(BUN)水平[(6.86±1.10)mmol/L]高于3月龄组[(5.73±0.47)mmol/L],差异有统计学意义(P<0.05);而血肌酐(SCR)、血糖(GLU)和胆固醇(CHOL)水平三组差异无统计学意义(P>0.05)。24月龄组肾重[(5.01±1.00)g]和尿蛋白/肌酐比值[(256±49.39)mg/mmoL]高于12月龄组[(3.25±0.50)g、(164.81±38.31)mg/mmoL],差异有统计学意义(P<0.05)。②12月龄组和24月龄组TLR2、TLR3、TLR4、TLR5、TLR11表达水平均高于3月龄组,24月龄组TLR1和TLR3水平高于3月龄组,24月龄组TLR9水平高于3月龄组,差异均有统计学意义(P<0.05);三组TLR6、TLR7、TLR10水平差异无统计学意义(P>0.05);TLR8未检测到。24月龄组TLR1、TLR2、TLR3、TLR4、TLR5、TLR11水平高于12月龄组,差异均有统计学意义(P<0.05)。③12月龄组和24月龄组IK-Bα和活化的磷酸化NF-κB p65(Phospho-NF-κB p65)水平高于3月龄组,差异有统计学意义(P<0.05);24月龄组NF-κB p65水平高于3月龄组,差异有统计学意义(P<0.05)。24月龄组NF-κB p65和Phospho-NF-κB p65水平高于12月龄组,差异有统计学意义(P<0.05)。④24月龄组CCL3、CCL4、CCL5、CD80、TNF-α和IL-12b水平高于3月龄组,差异有统计学意义(P<0.05);12月龄组CD80和IL-12b水平低于3月龄组,差异有统计学意义(P<0.05)。24月龄组CCL3、CCL4、CCL5、CD80、TNF-α和IL-12b高于12月龄组,差异有统计学意义(P<0.05)。结论 TLRs系统可能通过激活NF-κB信号通路、促进炎症因子的表达而在肾脏衰老过程中发挥重要作用。

Objective To observe the expression changes of Toll-like receptors in aging process of rat kidneys. Methods Western blot and qRT-PCR were used to analyzed the expression changes of TLRs, NF-κB signal pathway molecules and inflammatory factors including CCL3, CCL4, CCL5, CD80, TNF—α and IL-12b in the kidney tissues from rats in 3-month-old group （young group, n = 20）, 12-month-old group （middle group, n = 20） and 24-month-old group （old group, n = 20）. Results （~）The weight, kidney weight, TG and urinary albumin/creatinine ratio in 12- month-old group [（466.86±32.62） g, （43.25±0.50） g, （2.32±0.46） mmol/L, （164.81±38.31） mg/mmoL] and 24-monthold group [（617.8±57.34） g, （5.01±1.00） g, （3.22±0.82） mmol/L, （256.00±49.39） mg/mmoL] were all higher than those in 3-month-old group [（236.3±12.28） g, （1.67±0.68） g, （1.20±0.32） retool/L, （146.01±22.72） mg/mmoL], the differences were statistically significant （P 〈 0.05）; BUN in 24-month-old group [（6.86±1.10） mmol/L] was higher than that in 3-month-old group [（5.73±0.47） mmol/L], the difference was statistieally significant （P 〈 0.05）; the differences of SCR, GLU, CHOL in the 3 groups were not statistieally significant （P 〉 0.05）; kidney weight and urinary albumin/creatinine ratio in 24-month-old group [（5.01±1.00） g, （256±49.39） mg/mmoL] were higher than those in 12-month-old group [（3.25±0.50） g, （164.81 ±38.31） mg/mmoL], the differences were statistically significant （P 〈 0.05）. ②TLR2, TLR3, TLR4, TLR5, TLR11 in 12-month-old group and 24-month-old group were all higher than those in 3-month- old group, TLR1 and TLR3 in 24-month-old group were higher than those in 3-month-old group, TLR9 in 24-month-old group were higher than those in 3-month- old group, the differences were statistically significant （P 〈 0.05）; the differences of TLR6, TLR7, TLR10 in 3 groups were not statistically significant （P 〉 0.05）; TLR8 was not detected; TLR1, TLR2, TLR3, TLR4, TLR5, TLRll in 24-month-old group were higher than those in 12- month-old group, the differences were statistically significant （P 〈 0.05）. ③IK-Bα and Phospho-NF-κB p65 in 24- month-old group and 12-month-old group were higher than those in 3-month-old group, the differences were statisti- cally significant （P 〈 0.05）; NF-κB p65 in 24-month-old group was higher than that in 3-month-old group, the dif- ference was statistically significant （P 〈 0.05）; NF-κB p65 and Phospho-NF-κB p65 in 24-month-old group were higher than those in 12-month-old group, the difference was statistically significant （P 〈 0.05）. @CCL3, CCIA, CCL5, CD80, TNF—α and IL-12b in 24-month-old group were higher than those in 3-month-old group, the differences were statistically significant （P 〈 0.05）; CD80 and IL-12b in 12-month-old group were lower than those in 3-month-old group, the differences were statistically significant （P 〈 0.05）; CCL3, CCIA, CCL5, CD80, TNF—α and IL-12b in 24- month-old group were higher than those in 12-month-old group, the differences were statistically significant （P 〈 0.05）. Conclusion TLRs may play an important role in the regulation of the kidney aging by activating NF-κB signal pathway and promoting the expression of inflammatory factors.