水飞蓟素对糖尿病视网膜病变视网膜的保护作用

Protective effect of silymarin on retina of diabetic retinopathy

目的通过测定糖尿病大鼠视网膜内核层(INL)、外核层(ONL)厚度,视网膜电图(ERG)a波、b波幅度,细胞凋亡率来探讨水飞蓟素对糖尿病视网膜病变(DR)的视网膜保护作用。方法30只7周龄雄性SD大鼠随机分为正常对照组、高糖组、高糖治疗组,每组10只。高糖组采用腹腔注射70mg/kg链脲佐菌素建立模型,高糖治疗组每日应用水飞蓟素150mg/kg灌胃。28周后予以ERG检测,测量a波、b波的幅度。处死大鼠后制作视网膜切片测定INL和ONL厚度,TUNEL法检测视网膜细胞凋亡率。结果INL及ONL厚度高糖组低于正常对照组(P<0.05),高糖治疗组高于高糖组(P<0.05);正常对照组a波幅度高于高糖组及高糖治疗组(P<0.05),正常对照组及高糖治疗组b波幅度高于高糖组(P<0.05);高糖治疗组的细胞凋亡率均低于高糖组(P<0.05)。结论水飞蓟素对糖尿病大鼠的视网膜组织结构、功能具有改善作用,其作用机制可能与抑制视网膜细胞凋亡有关。

Objective To investigate the protective effect of silymarin on diabetic retinopathy(DR)by measuring the thickness of retinal inner layer(INL),outer nuclear layer(ONL),electroretinogram(ERG)a wave,b wave amplitude and cell apoptosis rate in diabetic rats.Methods Thirty male rats aged 7 weeks were randomly divided into normal control group,high glucose group and high glucose treatment group,with 10 rats in each group.The high glucose group was established by intraperitoneal injection of 70 mg/kg streptozotocin.The high glucose treatment group was administered with silymarin 150 mg/kg daily.After 28 weeks,the ERG test was performed to measure the amplitude of the a wave and the b wave.After the rats were killed,retinal sections were made to measure the thickness of INL ONL,and TUNEL method was used to detect the apoptosis rate of retinal cells.Results The thickness of INL and ONL in the high glucose group was lower than the normal control group(P<0.05),and the thickness of the INL and ONL in high glucose treatment group was between the two(P<0.05).The amplitude of the a wave in the normal control group was higher than both high glucose group and the high glucose treatment group(P<0.05),the b wave amplitude of the normal control group and the high glucose treatment group was higher than the high glucose group(P<0.05).The cell apoptosis rate of the high glucose treatment group was lower than high glucose group(P<0.05).Conclusion Silymarin can improve the structure and function of retina in diabetic rats,and its mechanism may be related to inhibition of retinal cell apoptosis.