Omega-3 polyunsaturated fatty acids preserve retinal function in type 2 diabetic mice

Area of Science:

• Ophthalmology
• Endocrinology
• Nutritional Science

Background:

• Diabetic retinopathy (DR) involves retinal microvascular damage and neuronal compromise, often exacerbated by hyperglycemia and dyslipidemia.
• Omega-3 (ω-3) polyunsaturated fatty acids (PUFAs) have shown protective effects in other forms of retinopathy.

Purpose of the Study:

• To investigate the efficacy of ω-3 PUFAs in preserving retinal function in a mouse model of type 2 diabetes mellitus (T2DM).
• To assess the impact of ω-3 PUFA supplementation on visual function, retinal integrity, and glucose metabolism in diabetic mice.

Main Methods:

• Male leptin-receptor-deficient (db/db) mice, a model for T2DM, were fed diets enriched with either ω-3 or ω-6 PUFAs for 22 weeks.
• Visual function was evaluated using electroretinography at multiple time points.
• Retinal capillary and neuronal integrity, along with glucose challenge responses, were assessed.

Main Results:

• Mice fed an ω-3 PUFA-enriched diet exhibited preserved retinal function, comparable to non-diabetic controls.
• Conversely, retinal function deteriorated in diabetic mice fed an ω-6 PUFA-rich diet.
• ω-3 PUFA supplementation enhanced the diabetic mice's response to glucose challenge, independent of cytoprotective or anti-inflammatory mechanisms.

Conclusions:

• Dietary ω-3 PUFAs demonstrate significant benefits for visual function in T2DM.
• The findings suggest that dyslipidemia negatively impacts retinal function in diabetes.
• Increasing ω-3 PUFA intake may be a safe, inexpensive strategy to slow vision loss in diabetic patients.