Aqueous humor DEL-1 and IL-17 levels unchanged in diabetic cataract patients without retinopathy

Early detection of diabetic retinopathy (DR) is crucial for preventing vision loss in diabetes patients. IL-17 is a known proinflammatory cytokine implicated in diabetes-related microvascular and ocular inflammatory processes, particularly in DR. Conversely, DEL-1 is an endogenous anti-inflammatory molecule that counter-regulates IL-17-mediated immune responses and contributes to vascular and immune homeostasis. Current diagnostic methods often detect DR only after significant damage has occurred, highlighting a need for early biomarkers to identify subclinical ocular inflammation before overt retinopathy develops.

This case-control study collected aqueous humor samples during cataract surgery from two groups: type 2 diabetic cataract patients without diabetic retinopathy (n=33) and non-diabetic cataract patients (n=28) as controls. Concentrations of DEL-1 and IL-17 in the aqueous humor were precisely measured using enzyme-linked immunosorbent assay (ELISA). Researchers also performed correlation analyses to investigate associations between biomarker levels and various clinical parameters, including age, duration of diabetes, fasting blood glucose, HbA1c, and macular thickness.

Mean aqueous humor DEL-1 levels were 0.27 ± 0.21 pg/mL in diabetic cataract patients without retinopathy and 0.36 ± 0.30 pg/mL in non-diabetic controls. For IL-17, mean levels were 59.82 ± 22.16 pg/mL and 59.78 ± 20.73 pg/mL, respectively. Crucially, no statistically significant differences were observed between the groups for either biomarker, with p-values of p=0.305 for DEL-1 and p=0.839 for IL-17. Correlation analyses also found no significant associations between these biomarker levels and clinical parameters such as diabetes duration or HbA1c.