Do Nutrients and Nutraceuticals Play a Role in Diabetic Retinopathy? A Systematic Review

Abstract

Diabetic retinopathy (DR) is a multifactorial neuro-microvascular disease, whose prevalence ranges from 25% to 60% of subjects affected by diabetes mellitus, representing the main cause of legal blindness in adults of industrialized countries. The treatment of advanced stage of DR is based on invasive and expensive therapies, while few strategies are available for the early stage or prevention. The mechanisms underlying DR involve a complex interplay between the detrimental effects of hyperglycemia, dyslipidemia, hypoxia, and oxidative stress, providing several pathways potentially targeted by nutrients and nutraceuticals. In this study, we conducted a systematic review of observational and interventional studies, evaluating the effect of nutrients and/or nutraceuticals on the risk of DR and their potential use for the treatment of patients with DR. The analysis of the 41 included studies (27 observational and 14 interventional studies) suggests a promising preventive role of some nutrients, in particular for vitamins B (i.e., B1 and B12), D, and E. However, further investigations are necessary to clarify the potential clinical application of nutraceuticals in the prevention and treatment of DR.

Semaglutide-eye-catching results

“…Despite United Kingdom Prospective Diabetes Study results showing that each 1% reduction in HbA1c was associated with a 37% reduction in the development of retinopathy in patients with T2DM[ 14 ], conflicting results were also reported concerning the association of tight glucose control with the worsening of previously identified DR signs[ 15 ]. However, along with persistent hyperglycemia, risk factors for DR onset include the patient’s age, diabetes duration, and high blood pressure, together with genetic predisposition, smoking habits, anemia, non-Caucasian ethnicity, and hyperlipidemia[ 16 - 19 ]. Indeed, pre-existing DR progression can also be related to the magnitude of HbA1c reduction, where data support the evidence of temporary, paradoxical DR worsening during the first three to 36 mo of initiation of intensive glucose lowering before the long-term benefits of glucose optimization become apparent[ 13 , 20 , 21 ].…”

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

“…Despite obvious limitations, preclinical and clinical studies strongly support the role of nutraceuticals in the management of sight-threatening retinopathies [ 25 , 88 , 89 ], as thoroughly reviewed in other recent publications [ 87 , 90 , 91 ]. Differently, in the present review, we aim to provide a pragmatic overview of the intersection between the use of pharmaceutical drugs and food supplements intended as nutraceuticals.…”

Antioxidant Activity of Cyanidin-3-O-Glucoside and Verbascoside in an in Vitro Model of Diabetic Retinopathy

“…Currently, the International Classification of Diabetic Retinopathy and Diabetic Macular Edema considers the use of antioxidants as potentially effective in the treatment of mild forms of NPDR and DME, while no indications are given for their use in the treatment of PDR [60]. Studies from in vitro and in vivo models suggest that nutraceuticals may relieve the pathophysiological complications of DR such as inflammation and neurodegeneration, by an enhancement of the antioxidant defense systems and the consequent reduction of ROS accumulation [61,62]. The main dietary antioxidants are found in colored foods, and are represented by polyphenols and carotenoids (Fig.…”