叔丁基对苯二酚对糖尿病大鼠视网膜的保护作用及其机制研究

目的　探讨叔丁基对苯二酚（tert-Butylhydroquinone，tBHQ）对糖尿病大鼠视网膜的保护作用及其机制，为DR防治提供新靶点。方法　18只雄性SD大鼠随机分成3组:正常组、糖尿病组（高脂高糖饮食）和tBHQ干预组（高脂高糖饮食中加入质量分数1%tBHQ），后两组饮食干预4周后建立糖尿病大鼠模型，饮食干预3个月后处死各组大鼠。采集大鼠空腹血用于测定生化和胰岛素相关指标，HE染色观察大鼠视网膜各层组织变化，使用miRNA表达谱芯片测量大鼠视网膜差异性miRNA，实时定量PCR验证特定miRNA在3组大鼠视网膜的表达水平，分析差异性miRNA的相关通路。结果　tBHQ干预组［（15.073±7.079）mmol·L^-1］较正常组［（7.635±1.421）mmol·L^-1］空腹血糖升高（P<0.05），较糖尿病组［（22.331±1.824）mmol·L^-1］降低（P<0.05）。tBHQ干预组［（47.961±15.256）μU·L^-1］血清胰岛素较正常组［（78.090±20.974）μU·L^-1］减少，而较糖尿病组［（17.533±3.959）μU·L^-1］增多（均为P<0.01）。HE染色结果示，糖尿病组大鼠视网膜出现严重水肿，各层结构不清，tBHQ干预组视网膜改变相对轻微。与糖尿病组大鼠相比，tBHQ干预组视网膜中miR-325-3p（>2.0倍）和miR-551b-3p（>1.5倍）上调，miR-652-3p（>2.0倍）下调。实时定量PCR验证miR-325-3p和miR-551b-3p为差异性miRNA，靶基因预测分析示miR-325-3p可介导21条信号通路。结论　tBHQ可能通过miR-325-3p介导的信号通路对2型糖尿病大鼠视网膜起保护作用。

Protective effects of tert-butylhydroquinone on the retina of diabetic rats and its mechanisms

Objective　To investigate the protective effect and mechanism of tert-butylhydroquinone (tBHQ) on the retina of diabetic rats and provide new targets for prevention of DR.Methods　Totally 18 male SD rats were randomly divided into three groups:normal group，diabetic group (high-glucose-high-fat diet) and tBHQ intervention group (addition of mass fraction of 1% tBHQ to a high-glucose-high-fat diet).After dietary intervention for 4 weeks of the last two groups，diabetic rat models were established.Rats in each group were sacrificed after 3 months of dietary intervention.The rats were sacrificed to collect the fasting blood for measuring the biochemical and insulin-related indicators.HE staining was used to observe the pathological changes of retinal tissue.The miRNA expression profile microarray was used to measure the differential miRNAs of rat retinas.The expression levels of specific miRNAs in the three groups of rat retinas were verified by PCR.The relevant pathways of differential miRNAs were analyzed.Results　The fasting blood glucose in the tBHQ intervention group ［(15.073 ±7.079)mmol·L^-1］was higher than that in the normal group［(7.635±1.421)mmol·L^-1］，which was lower than that in the diabetic group ［(22.331±1.824)mmol·L^-1］ (both P＜0.05).The serum insulin in the tBHQ intervention group ［(47.961±15.256)μU·L^-1］ was lower than that in the normal group ［(78.090±20.974)μU·L^-1］，but it was higher than that in the diabetic group［(17.533±3.959)μU·L^-1］ (both P＜0.01).Severe retinal edema appeared in the retina of the diabetic group，and the structural layer was unclear based on HE staining.The pathological changes of the retina in the tBHQ intervention group were slight.Compared with diabetic rats，miR-325-3p and miR-551b-3p were up-regulated (>1.5-fold) and miR-652-3p was down-regulated (>2.0-fold) in the tBHQ group.MiR-325-3p and miR-551b-3p were identified as differential miRNAs after PCR verification.By combining the results of the microarray experiments，we found that 21 pathways might be subject to miR-325-3p regulation from tBHQ treatment.Conclusion　tBHQ has protective effects on diabetic retina through miR-325-3p and its mediated signaling pathways.