Lutein May Have a Role In Visual Function And Retinal Damage In Diabetics

30 Jul 2014 --- OmniActive Health Technologies recently made public findings that examined lutein’s role on visual function and carbohydrate metabolism in STZ-induced diabetic rats. The study was conducted by leading research experts at the National Institute of Nutrition in Hyderabad, India.

Results showed that an innovative macular carotenoid formulation consisting of premium lutein and zeaxanthin isomers (Lutemax 2020) suppresses oxidative stress in tissue, can prevent free radicals from combining with retinal collagen and strengthens retinal collagen, significantly preventing reduction of retinal thickness.

Vijaya Juturu, Ph.D., F.A.C.N., Manager of Clinical and Scientific Affairs, OmniActive Health Technologies, presented the poster, “Lutein Improves Visual Function in Early Stage Streptozotocin-Induced Diabetic Rats” at this year’s International Symposium on Carotenoids in Park City, Utah (June 29-July 4). Dr. Juturu also delivered another talk, “Soluble Lutein (Lutemax 2020) Prevents Retinal Damage in Streptozotocin (STZ)-induced Diabetic Rats” at the 4th International Clinical and Experimental Ophthalmology Conference in Baltimore, Maryland (July 14-16).

“Diabetic retinopathy is the leading cause of blindness for diabetes mellitus sufferers and its worldwide prevalence is rapidly increasing as a consequence of a rise in obesity, changing patterns of diet and physical activity, and an aging population,” stated Dr. Jayant Deshpande, Chief Technical Officer, OmniActive Health Technologies. “The results of this study revealed that lutein and zeaxanthin isomers have great potential for the treatment of diabetic retinopathy, which can occur in both individuals with type 1 and type 2 diabetes.”

For this study, diabetes mellitus was induced in overnight-fasted animals by a single intra-peritoneal injection of STZ. Fasting blood glucose levels were measured 72 hours after the STZ injection. Animals having blood glucose levels higher than 150 mg/dl were considered diabetic rats. Twenty-nine male Wistar strain rats were divided into four groups: group I - control group receiving a standard diet; group II - diabetes mellitus group; group III - diabetes mellitus group plus regular lutein (RL, lutein 0.5%); and group IV - diabetes mellitus group plus soluble lutein (as Lutemax 2020 at 0.5%). All rats were housed in individual cages and maintained their respective diets for 12 weeks. Daily food intake and weekly body weights, fasting glucose and HbA1c levels were noted. ERG was performed. Lutein treatment minimized deterioration of b-wave/a-wave ratio and improved oscillatory potential (OP) in groups III and IV. Group IV showed a significant difference in sum of OP compared to Group II. These findings suggest lutein’s positive role in the eye health of individuals with diabetes mellitus.

Oxidative damage and growth factors are implicated in the pathogenesis of retinopathy in diabetes. Lutein significantly inhibits diabetes-induced retinal oxidative damage and elevation in VEGF and PDGF, and inhibits abnormalities associated with diabetic retinopathy. These findings further support the important antioxidant functions and roles that lutein and zeaxanthin isomers play in maintaining healthy vision.