Contents of chemokines in lacrimal fluid of the patients with diabetic retinopathy and type 2 diabetes mellitus

Abstract

Diabetic retinopathy is a serious microvascular complication of diabetes mellitus with chemokines playing an important pathogenetic role. However, the studies of chemokines in lacrimal fluid of the patients with diabetic retinopathy and type 2 diabetes mellitus (T2DM) are rarely performed. The aim of the study was to analyze the content of chemokines in lacrimal fluid of patients suffering from diabetic retinopathy and T2DM. When determining the concentration of chemokines in the lacrimal fluid, two clinical groups were formed: the main group of 56 elderly patients suffering from diabetic retinopathy and T2DM, and a control group of 48 age-matched persons with T2DM, however, without diabetic retinopathy. The diagnosis of diabetic retinopathy was performed after comprehensive ophthalmological examination using various modern techniques and applying the criteria of the All-Russian Association of Ophthalmologists “Diabetes mellitus: diabetic retinopathy, diabetic macular edema”. The chemokine levels in the lacrimal fluid were determined in the morning on the MAGPIX device (USA). The changed contents of chemokines was shown in lacrimal fluid of patients with diabetic retinopathy and T2DM, in comparison with patients suffering from T2DM in absence of diabetic retinopathy. In elderly patients with diabetic retinopathy and T2DM, a decreased content of GROα/ CXCL1, RANTES/CCL5 and MIP-1α/CCL3 was revealed in lacrimal fluid, at a statistically significant difference as related to controls. At the same time, the content of GROα/CXCL1 chemokine in lacrimal fluid was decreased most significantly, (38.24±2.57 in the main group versus 13.61±1.74 pg/mL in the comparison group). The level of RANTES/CCL5 decreased to 0.92±0.16 pg/mL versus 1.69±0.18 pg/mL (p < 0.001); MIP-1α/CCL3, to 2.06±0.71pg/mL versus 3.79±0.64 pg/mL, respectively. However, the proportion of chemokines in the lacrimal fluid of patients with diabetic retinopathy and T2DM was significantly inceased in all cases. This finding concerns MCP-1/CCL2, IP-10/CXCL10, and SDF1α/CXCL12. The content of IP-10/CXCL10 in lacrimal fluid increased to maximal values of 38.24±2.57 pg/mL in the patients with diabetic retinopathy and T2DM compared with 13.61±1.74 pg/mL in patients with diabetes mellitus without diabetic retinopathy, MCP-1/CCL2 to 742.34±0.89 pg/mL compared to 633.72±0.64 pg/mL, respectively; SDF1α/ CXCL12, to 264.78±7.82 pg/mL compared to 213.49±6.08 pg/mL. In addition, the interrelations between studied chemokines in patients with diabetic retinopathy and type 2 diabetes mellitus are more pronounced than in comparison group as confirmed by large number of correlations in the main group. The results obtained expand the knowledge on the effects of chemokines in lacrimal fluid upon development of diabetic retinopathy.