Objective: To investigate the possible role of pyroptosis of lens epithelial cells (LECs) in the occurrence of diabetic cataract. Methods: Experimental research. A total of 70 cataract lens anterior capsule and aqueous humor samples were obtained from 70 eyes (70 patients) with cataracts in the operation room of Tianjin Medical University Eye Hospital between March 2020 and November 2020. Patients were divided into the non-diabetic and diabetic groups, with 35 patients (35 eyes) in each group. The expressions of Nod like receptor protein 3 (NLRP3), cysteine-aspartic proteases 1 (caspase-1) and Gasdermin D protein (GSDMD) in the lens anterior capsule were detected by Western blotting, real-time quantitative PCR and immunohistochemical staining. Interleukin (IL)-1β and IL-18 inaqueous humor were detected by enzyme-linked immunosorbent assay (ELISA). The independent sample t-test was used for statistical analysis. Results: The age was (70±9) years in the diabetic group and (71±8) years in the non-diabetic group. There was no significant difference in age and gender distribution between the two groups (both P>0.05). Western blotting analysis showed that the expression levels of NLRP3, caspase-1 and GSDMD protein in the LECs of anterior capsule were 1.11±0.06, 0.95±0.04 and 0.39±0.03 in the diabetic group, significantly higher than those of the non-diabetic group (0.81±0.04, 0.33±0.11 and 0.16±0.04; t=4.38, 5.36, 4.63; all P<0.05). Real-time quantitative PCR showed that the levels of NLRP3, caspase-1 and GSDMD mRNA in the LECs of anterior capsule were 1.98±0.07, 54.36±4.88 and 6.98±1.18 in the diabetic group, significantly higher than those of the non-diabetic group (1.38±0.16, 15.31±1.51 and 2.41±0.95; t=3.49, 7.64, 3.00, all P<0.05). Immunohistochemical staining showed that the average gray values of NLRP3, caspase-1 and GSDMD in the diabetic group were higher than those of the non-diabetic group (all P˂0.01). ELISA showed that the levels of IL-1β and IL-18 in the aqueous humor were (4.178±0.028) fg/L and (20.983±0.018) fg/L in the diabetic group, significantly higher than those of the non-diabetic group [(4.063±0.017) fg/L and (20.509±0.073) fg/L; t=20.63, 37.21; both P˂0.01]. Conclusion: Caspase-1-mediated pyroptosis of LECs and the release of inflammatory mediators induced by pyroptosis may be involved in the occurrence and development of diabetic cataract.
目的： 探究晶状体上皮细胞焦亡在糖尿病性白内障发生中的可能作用。 方法： 实验研究。选择2020年3至11月就诊于天津医科大学眼科医院行白内障摘除手术的70例（70只眼）患者，收集手术中房水及晶状体前囊膜。根据是否伴有2型糖尿病，分为糖尿病组和非糖尿病组，每组35例（35只眼）。采用Western印迹分析、实时定量PCR和免疫组织化学染色检测晶状体前囊膜Nod样受体蛋白3（NLRP3）、半胱氨酸天冬氨酸蛋白酶1（caspase-1）、Gasdermin D蛋白（GSDMD）的表达，采用酶联免疫吸附测定法检测房水中白细胞介素（IL）1β和IL-18，并进行两组间比较。主要的统计学方法为独立样本t检验。 结果： 糖尿病组年龄为（70±9）岁，非糖尿病组年龄（71±8）岁，两组年龄及性别分布差异均无统计学意义（均P>0.05）。Western印迹分析显示糖尿病组前囊膜晶状体上皮细胞中NLRP3、caspase-1、GSDMD蛋白的表达水平分别为1.11±0.06、0.95±0.04、0.39±0.03，均高于非糖尿病组的0.81±0.04、0.33±0.11、0.16±0.04，差异均有统计学意义（t=4.38、5.36、4.63，均P<0.05）。实时定量PCR结果显示糖尿病组前囊膜晶状体上皮细胞中NLRP3、caspase-1、GSDMD mRNA水平分别为1.98±0.07、54.36±4.88、6.98±1.18，均高于非糖尿病组的1.38±0.16、15.31±1.51、2.41±0.95，差异均有统计学意义（t=3.49、7.64、3.00，均P<0.05）。免疫组织化学染色显示糖尿病组晶状体前囊膜中NLRP3、caspase-1、GSDMD灰度值亦均高于非糖尿病组，差异均有统计学意义（均P˂0.01）。酶联免疫吸附测定法显示糖尿病组房水中IL-1β、IL-18水平分别为（4.178±0.028）、（20.983±0.018）fg/L，均高于非糖尿病组的（4.063±0.017）、（20.509±0.073）fg/L，差异均有统计学意义（t=20.63、37.21，均P˂0.01）。 结论： caspase-1介导的晶状体上皮细胞焦亡以及焦亡导致的炎性介质释放可能参与了糖尿病性白内障的发生和发展。.