Evaluation of tear inflammatory cytokines concentration in diabetic patients at different stages

Abstract

Diabetic retinopathy (DR), which is one of the most important causes of blindness in Western societies, is the most common type of microvascular disease associated with diabetes and there is growing evidence of the role of inflammation in its development. This study was designed with the hypothesis that the measurement of tear cytokines in diabetic patients may predicts the ocular inflammatory status and thus facilitate control of disease progression. In this regard, tear concentrations of three types of cytokines with different angiogenic properties including IL-1RA with anti-angiogenic properties, IL-8 with pro-angiogenic properties and TNF-α with dual anti-angiogenic and pro-angiogenic properties in diabetic patients without retinopathy, With non-proliferative retinopathy and with proliferative retinopathy, were measured and compared with healthy individuals (without diabetes) as a control group. Methods: After selecting the participants, tear samples were collected from a total of 90 people including; 20 non-diabetic patients (control group), 20 diabetic patients without retinopathy (DNR), 25 diabetic patients with non-proliferative retinopathy (NPDR) and 25 diabetic patients with proliferative retinopathy (PDR), and the Concentrations of IL-1RA, IL-8 and TNF-α were measured by “enzyme-linked immunosorbent assay” method. Then, the obtained data were statistically analyzed. Results: The results showed that in the tear sample of diabetics, the concentrations of TNF-α and IL-8 were higher than the control group, while tear level of IL-1RA was significantly low in diabetics compared to healthy individuals.