AIM: To investigate the relationship between serum long non-coding RNA(lncRNA)without distal homeobox 6 antisense 1(DLX6-AS1)and microRNA(miR)-335-3p and microvascular damage in patients with diabetic retinopathy(DR).

METHODS: A total of 160 patients with type 2 diabetes mellitus(T2DM)in our hospital from February 2019 to December 2021 were prospectively selected and divided into non-DR group(NDR, n=69), non-proliferative DR group(NPDR, n=48)and proliferative DR group(PDR, n=43)according to DR staging criteria. The serum levels of lncRNA DLX6-AS1, miR-335-3p, vascular endothelial growth factor(VEGF), endothelial cells(ECs), and endothelial progenitor cells(EPCs)were compared among the three groups. Pearson method was used for correlation analysis. Logistic regression model was used to analyze the influencing factors of DR in patients with T2DM.

RESULTS: The expression level of serum miR-335-3p and the proportion of EPCs in NDR, NPDR and PDR groups were gradually decreased, while the expression levels of DLX6-AS1 and VEGF and the proportion of ECs were gradually increased(all P<0.05). Serum lncRNA DLX6-AS1 was negatively correlated with miR-335-3p in patients with DR(r=-0.668, P<0.01). The expression levels of serum lncRNA DLX6-AS1 and miR-335-3p in NPDR and PDR groups were negatively correlated(r=-0.647, -0.675, all P<0.01), lncRNA DLX6-AS1 was positively correlated with VEGF(r=0.619, 0.630, all P<0.01), and VEGF was negatively correlated with miR-335-3p(r=-0.625, -0.649, all P<0.01). In the PDR group, lncRNA DLX6-AS1 was positively correlated with ECs, while it was negatively correlated with EPCs(r=0.528, -0.594, all P<0.01). The miR-335-3p was negatively correlated with ECs and it was positively correlated with EPCs(r=-0.554, 0.586, all P<0.01). Multivariate regression analysis showed that lncRNA DLX6-AS1(OR=2.484, 95%CI: 1.366-4.516), miR-335-3p(OR=2.171, 95%CI: 1.218-3.871)and VEGF(OR=1.603, 95%CI: 1.115-2.304)were risk factors for DR in T2DM patients(all P<0.05).

CONCLUSION:lncRNA DLX6-AS1 is up-regulated and miR-335-3p is down-regulated in serum of DR patients. lncRNA DLX6-AS1 is negatively correlated with miR-335-3p. Abnormal expressions of both are related to microvascular damage in DR patients.