Folic acid lowers homocysteine levels in diabetes patients taking metformin
MedWire News: Folic acid supplementation decreases homocysteine (Hcy) levels in individuals with Type 2 diabetes patients under metformin treatment, Iranian researchers report.
Supplementation with folic acid appears to improve glycemic control and insulin resistance (IR) as well as restoring folate and B12 levels, they say.
Led by Bahram Gagari (Tabriz University of Medical Sciences, Iran), the team evaluated the effects of folic acid supplementation on indices of glycemic control, insulin resistance, and lipid profile in overweight, diabetic men who had been under metformin treatment (at least 1500mg per day) for a minimum of six months.
As reported in the journal Diabetes Research and Clinical Practice, the researchers randomly assigned 24 of the men to a folic acid group and 24 to a placebo group where they received 5 mg per day of either folic acid or placebo for a period of eight weeks.
The researchers recorded the patients' fasting blood glucose (FBG), glycated hemoglobin (HbA1c), serum insulin and IR, serum folate and B12, and plasma Hcy levels at baseline and once more after the eighth week of the study. They used homeostasis model assessment (HOMA) to quantify IR levels (HOMA-IR).
The authors found that 8 weeks of folic acid supplementation led to a significant decrease in levels of insulin, HOMA-IR, and HbA1c (16.2%, 20.5%, and 7.5%, respectively). There was also a substantial 21.2% drop in Hcy levels and a 7.5% reduction in FBG.
In addition, the authors observed increases in serum folate and B12 levels of 19% and 17.3%, respectively, whereas no significant changes occurred in the placebo group.
They suggest that one possible mechanism by which folic acid decreases blood glucose concentration may be that the active form of Hcy (Hcy thiolactone), may inhibit phosphorylation of insulin receptor β-subunit and decrease phosphatidylinositol 3-kinase activity, resulting in a reduction in insulin-stimulated glycogen synthesis.
"This naturally leads to insulin resistance and blood glucose increase," they say.
The team say that the trial's findings suggest folic acid supplementation offers a safe and inexpensive therapy for lowering homocysteine and improving the overall management of diabetic patients.
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By Sally Robertson