The recent study involved 99 volunteers with mild to moderate non-proliferative DR, who were given either 400 mg of MaGPE —derived from Aglianico cultivar grapes—or a placebo twice daily for six months.
The MaGPE group showed a notable reduction in central retinal thickness (CRT), increased levels of reactive oxygen metabolite derivatives (dROMs) and decreased oxidized low-density lipoprotein (ox-LDL) levels.
“These findings support the potential of MaGPE supplementation as a protective strategy to mitigate the progression of DR in association with standard DR therapies, particularly through the enhancement of the anatomical and functional integrity of the retina,” the authors from Italy wrote.
Nutraceuticals for eye health
DR affects about 22% of diabetics and can lead to preventable blindness, particularly in the working-age population. It is expected to increase significantly from 103 million in 2020 to 160 million by 2045.
The pathogenesis of DR involves multiple mechanisms such as oxidative stress and vascular endothelial growth factor (VEGF) -induced issues, leading to diabetic macular edema (DME), the primary cause of vision loss in diabetics.
According to the authors, common pharmacological treatments primarily target specific pathways implicated in the disease’s pathogenesis, such as VEGF inhibition, rather than oxidative stress. However, oxidative stress is reportedly a key factor in DR, as it influences the regulation of various biochemical pathways, mitochondrial dysfunction and hypoxia-driven VEGF synthesis.
Nutraceuticals, including those derived from grape pomace, have shown promise due to their antioxidant and vascular-protective properties, and some research has found that these compounds can mitigate DR progression by reducing oxidative stress and improving visual parameters.
Grape pomace extract
To participate in the study, volunteers underwent physical examinations, laboratory tests and measurements of blood pressure and heart rate.
Serum levels of reactive oxygen metabolite derivatives (d-ROMs) and oxidized low-density lipoproteins (oxLDLs) were monitored as biomarkers related to oxidative stress at the beginning of the study, three months and six months.
Results demonstrated that MaGPE supplementation significantly benefited patients with DR, particularly by reducing CRT and improving best-corrected visual acuity (BCVA).
Additionally, MaGPE appeared to stabilize vascular perfusion and effectively reduce oxidative stress biomarkers, suggesting its potential to mitigate DR progression by targeting oxidative stress and vascular integrity.
“The significant improvements observed for CRT and BCVA values in the MaGPE group, compared to the placebo group, demonstrate its potential as an effective intervention for reducing retinal swelling and enhancing visual acuity in patients with DR,” the researchers concluded.
They added that further research is needed to gain a better understanding of the molecular and cellular mechanisms behind the effects of supplementation.
Journal: Nutrients
2024, 16(17), 2850; doi: 10.3390/nu16172850
“From Vineyard to Vision: Efficacy of Maltodextrinated Grape Pomace Extract (MaGPE) Nutraceutical Formulation in Patients with Diabetic Retinopathy.”
Authors: Schiano, E. et al.