Effects of Folate Supplementation on Inflammatory Markers in Diabetes: A Systematic Review
Effects of Folate Supplementation on Inflammatory Markers in Diabetes: A Systematic Review
AmirHossein RahimBakhsh,1,*
1. Department of Comparative Biosciences, Faculty of Veterinary Medicine, University of Tehran, Tehran,Iran
Introduction: Diabetes is a chronic metabolic disorder characterized by persistent hyperglycemia, which often leads to oxidative stress and inflammation. Chronic inflammation is a key factor in the pathogenesis and progression of diabetes and its complications such as neuropathy, nephropathy, and cardiovascular diseases. High levels of inflammatory markers, such as C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukins like IL.6, are commonly observed in individuals with diabetes. Folate, a naturally occurring form of vitamin B9 that serves as an important cofactor for one-carbon (1C) transfer reactions, has been shown to modulate inflammatory pathways and reduce systemic inflammation.
Methods: We systematically searched the PubMed, Scopus, and Google Scholar databases to investigate the effect of folate supplementation on inflammatory markers between 2005 and 2024. The search terms included “folate”, “inflammation”, “diabetes”, “inflammatory markers”, and “cytokines”. Studies that investigated the effects of folate supplementation on inflammatory markers in diabetic rats, focusing on cytokines, such as TNF-α, IL-6, IL-1β, IL-10, and C-reactive protein (CRP) levels, were included. Studies without a control group or those that did not present results were excluded.
Results: Of the 18 relevant studies reviewed, out of which 5 were excluded due to insufficient data. 13 studies reported a significant reduction in inflammatory markers following folate supplementation. The results show that folate supplementation reduced the levels of important cytokines in this pathway, including TNF-α, IL-6, IL-1β, and CRP, by suppressing the activity of the NF-κB pathway. In contrast, folate decreased the levels of homocysteine, an inflammatory marker, and increased the levels of anti-inflammatory cytokines, such as IL-10.
Conclusion: Our research suggests that folate supplementation is effective in reducing systemic inflammation in diabetic rats by decreasing inflammatory markers, reducing oxidative stress, and lowering homocysteine levels. Nevertheless, further investigations are required to elucidate the optimal dosage and mechanisms of action of folate in diabetic models.