糖尿病视网膜病变患者血清Metrnl和鸢尾素水平变化及其临床意义

目的　探讨糖尿病视网膜病变（DR）患者血清Metrnl和鸢尾素（Irisin）水平变化及其临床意义，以期为DR患者的诊治提供新思路。方法　收集2020年3月至2021年9月就诊于济南市第八人民医院的2型糖尿病患者120例，根据是否合并视网膜病变和病变程度分为非DR组（NDR组，n=39）、非增生型DR组（NPDR组，n=43）、增生型DR组（PDR组，n=38）。同期选取健康体检者40人为正常对照组（NC组）。抽取各受试者的静脉血，分离血清，采用酶联免疫吸附试验检测其血清Metrnl和Irisin水平，并测量体重指数（BMI）、空腹血糖（FPG）、甘油三酯（TG）、总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（HDL-C）、糖化血红蛋白（HbA1c）、空腹胰岛素（FINS）、超敏C反应蛋白（hs-CRP）、白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、单核细胞趋化蛋白1（MCP-1）、胰岛素抵抗指数（HOMA-IR）等指标。采用Spearman相关分析法分析患者血清Metrnl与Irisin水平、糖尿病病程、BMI、FPG、TG、TC、LDL-C、HDL-C、HbA1c、FINS、hs-CRP、IL-6、TNF-α、MCP-1、HOMA-IR的相关性。采用受试者工作特征（ROC）曲线分析血清Metrnl和Irisin水平对DR的诊断价值，采用多因素logistic回归分析DR发生的影响因素。结果　NDR组、NPDR组和PDR组患者血清Metrnl和Irisin水平均低于NC组（均为P<0.05）。NPDR组和PDR组患者血清Metrnl和Irisin水平均低于NDR组（均为P<0.05），且PDR组患者血清Metrnl和Irisin水平降低更明显，NPDR组和PDR组患者血清Metrnl和Irisin水平比较差异均有统计学意义（均为P<0.05）。相关性分析显示，患者血清Metrnl水平与Irisin水平呈正相关（r=0.612，P<0.01），但与DM病程（r=-0.473，P=0.000）、TG（r=-0.286，P=0.021）、HbA1c（r=-0.347，P=0.007）、HOMA-IR（r=-0.179，P=0.034）、TNF-α（r=-0.328，P=0.018）、IL-6（r=-0.196，P=0.030）和MCP-1（r=-0.272，P=0.025）均呈负相关。ROC分析结果显示，血清Metrnl和Irisin诊断DR的ROC曲线下面积分别为0.762和0.674，而两者联合诊断DR的ROC曲线下面积为0.858，灵敏度和特异度均高于血清Metrnl或血清Irisin单独诊断。logistic回归分析结果显示，糖尿病病程、HbA1c、MCP-1、血清Irisin和Metrnl水平均为DR发生的独立影响因素。结论　DR患者血清Metrnl和Irisin水平降低，且与患者病情程度相关，可能在糖脂代谢和炎症反应方面影响DR发生发展，对DR的诊断有一定预测价值。

Changes in serum Metrnl and Irisin levels in diabetic retinopathy and their clinical significance

Objective　To explore the changes in serum Metrnl and Irisin levels in patients with diabetic retinopathy (DR) and their clinical significance, so as to provide new ideas for the diagnosis and treatment of DR. Methods　Totally 120 patients with type 2 diabetes treated in the Eighth People’s Hospital of Jinan from March 2020 to September 2021 were enrolled and divided into the non-DR group (NDR group, n=39), non-proliferative DR group (NPDR group, n=43), and proliferative DR group (PDR group, n=38). Forty healthy people in the same period were selected into the normal control group (NC group). Venous blood was drawn, and serum was separated. Metrnl and Irisin levels in the serum were detected by ELISA. Meanwhile, the body mass index (BMI), fasting plasma glucose (FPG), triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), glycosylated hemoglobin (HbA1c), fasting insulin (FINS), high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), monocyte chemotactic protein-1 (MCP-1), and homeostatic model assessment of insulin resistance (HOMA-IR) were measured. Spearman’s correlation was used to analyze the correlation between serum Metrnl and Irisin levels, diabetic duration, BMI, FPG, TG, TC, LDL-C, HDL-C, HbA1c, FINS, hs-CRP, IL-6, TNF-α, MCP-1, and HOMA-IR. The receiver operating characteristic (ROC) curve was used to analyze the value of serum Metrnl and Irisin levels for DR diagnosis, and multivariate logistic regression was used to analyze the influencing factors of DR. Results　Serum Metrnl and Irisin levels in the NDR, NPDR and PDR groups were significantly lower than those in the NC group (all P<0.05). Serum Metrnl and Irisin levels in the NPDR and PDR groups were significantly lower than those in the NDR group (all P<0.05), while in the PDR group, they decreased more significantly. There was also a significant difference in serum Metrnl and Irisin levels between the NPDR and PDR groups (both P<0.05). Correlation analysis results showed that Metrnl level was positively correlated with Irisin level (r=0.612, P<0.01), and negatively correlated with diabetic duration (r=-0.473, P=0.000), TG (r=-0.286, P=0.021), HbA1c (r=-0.347, P=0.007), HOMA-IR (r=-0.179, P=0.034), TNF-α (r=-0.328, P=0.018), IL-6 (r=-0.196, P=0.030), and MCP-1 (r=-0.272, P=0.025). ROC analysis results showed that the area under the ROC curve for DM diagnosis with single serum Metrnl and Irisin levels was 0.762 and 0.674, while that for DM diagnosis with combined serum Metrnl and Irisin levels was 0.858, and the sensitivity and specificity of the latter were higher than those of the former.Logistic regression analysis results showed that the diabetic duration, HbA1c, MCP-1, serum Irisin and Metrnl levels were all independent factors affecting the development of DR. Conclusion　Serum Metrnl and Irisin levels are decreased in patients with DR, which is related to the severity of the disease. Serum Metrnl and Irisin levels may affect the occurrence and development of DR in terms of glycolipid metabolism and inflammatory reaction; thus, they have a predictive value for the diagnosis of DR.