C/EBP同源蛋白siRNA对糖尿病周围神经病变大鼠脊髓PERK-ATF4-CHOP通路mRNA的影响

Effect of CHOP siRNA on mRNA expression of PERK-ATF4-CHOP pathway in diabetic peripheral neuropathy rats

目的观察C/EBP同源蛋白(CHOP)siRNA对糖尿病周围神经病变(DPN)大鼠脊髓RNA依赖的蛋白激酶样内质网激酶(PERK)-转录活化因子4(ATF4)-CHOP通路相关因子mRNA表达的影响。方法采用高脂饲料喂养联合腹腔注射STZ复制DPN大鼠模型,分为空白对照组(Con)、模型对照组(Mod)、Con+CHOP siRNA组和Mod+CHOP siRNA组,分别鞘内注射转染试剂或CHOP siRNA,取L4～5下脊髓,检测PERK、真核翻译起始因子2a(eIF2a)、ATF4、CHOP、Bcl-2和Bax mRNA表达水平。结果与Con组比较,Mod组PERK[(1. 04±0. 03)vs(1. 40±0. 10)]、eIF2a[(1. 01±0. 14)vs(1. 64±0. 13)]、ATF4[(1. 02±0. 07)vs(1. 13±0. 07)]、CHOP[(1. 06±0. 05)vs(1. 25±0. 07)]和Bax[(1. 01±0. 04)vs(1. 75±0. 09)]mRNA表达均升高(P<0. 05或P<0. 01),而Bcl-2[(1. 00±0. 16)vs(0. 55±0. 06)]表达降低(P<0. 01);与Mod组比较,Mod+CHOP siRNA组PERK、eIF2a、ATF4、CHOP和Bax的mRNA表达降低(P<0. 01),Bcl-2表达升高(P<0. 01)。结论 CHOP siRNA干预能抑制DPN大鼠脊髓中PERK-CHOP凋亡通路,从而减轻脊髓脱髓鞘,缓解神经病变。

Objective To investigate the effect of C/EBP homologous protein (CHOP) on mRNA expressions of RNA -dependent protein kinase-like ER kinase (PERK)-activating transcription factor 4 (ATF4)-C/EBP homologous protein (CHOP) pathway in diabetic peripheral neuropathy (DPN) rats. Method 48 SD male rats were fed with high-fat diet combined with intraperitoneal injection of streptozotocin to replicate DPN Model. Then all the rats were divided into control group (Con), control+CHOP siRNA group (Con+CHOPsiRNA), Model control group (Mod) and CHOP siRNA group. Transfection reagent and CHOP siRNA were intrathecal injected. The mRNA expression levels of PERK, eukaryotic translation initiation factor 2a(eIF2a), ATF4, CHOP, Bcl-2 and Bax in the spinal cord were detected. Results The mRNA of PERK[(1.04±0.03) vs (1.40±0.10)], eIF2a[(1. 01 ±0.14) vs (1. 64 土 0.⑶],ATF4[(1.02 ±0.07) vs (1.13±0.07)],CHOP[(1. 06 ±0. 05) vs (1. 25±0.07)]and Bax[(1.01 ±0. 04) vs (1. 75±0.09)]were increased(P<0.01 or P<0.05), while the Bel-2[(1. 00±0. 16) vs (0. 55±0. 06)]mRNA was decreased in Mod group than in Con group (P<0. 01). The mRNA of PERK, eIF2a, ATF4, CHOP and Bax were decreased(P<0.01), while Bcl^2 was increased in Mod-r CHOP siRNA group than in Mod group (P<0. 01). Conclusion CHOP siRNA intervention can inhibit the PERK/CHOP pathway in DPN rat spinal cord, thus reducing demyelination and improving diabetic peripheral neuropathy.