Effect of metformin on serum interleukin-6 levels in polycystic ovary syndrome: a systematic review

Abstract

BackgroundMost women with polycystic ovary syndrome (PCOS) have insulin resistance, hyperinsulinemia, and elevated serum IL-6 levels. These elevated IL-6 levels may have links with insulin resistance and hyperandrogenism. Metformin may have beneficial effects on the chronic low-grade inflammatory background associated with PCOS.MethodsA systematic review was performed via PUBMED, EMBASE, and The Cochrane Library on PCOS studies published through November 30, 2013. Studies were selected that evaluated the effect of metformin on IL-6 levels in PCOS patients. Studies not containing adequate diagnosis information about PCOS or not excluding of other causes of hyperandrogenism were excluded.ResultsFive studies met the inclusion criteria. Of these, one study reported a significant decrease in IL-6 levels after metformin treatment in women with PCOS. Two studies reported that treatment-related reductions in IL-6 levels were significantly correlated with insulin metabolism. In the remaining two studies, plasma IL-6 levels did not change following metformin treatment.ConclusionsSerum IL-6 levels of PCOS patients may be influenced by metformin. Early application of metformin therapy may relieve chronic low-grade inflammation in women with PCOS. However, further investigations with larger samples are needed to better understand the effects of metformin on IL-6 levels and chronic inflammation in PCOS.

Associations between TNF-α and interleukin gene polymorphisms with polycystic ovary syndrome risk: a systematic review and meta-analysis

“…Most women with PCOS have insulin resistance, hyperinsulinemia, and elevated serum IL-6 levels. A recent meta-analysis suggested that the serum IL-6 levels of PCOS patients may be influenced by metformin, and early application of metformin therapy may relieve chronic lowgrade inflammation in women with PCOS [33]. Moreover, a similar positive association with the IL-6 -174 site was found for Alzheimer's disease and cancer, which are also recognized as inflammation-related diseases [34].…”

Effect of the Aquatic Extract of Stevia on the Serum Level of Interleukin-6 in Streptozotocin-Nicotinamide Induced Diabetic Rats

“…In a previous study, serum IL-6 level in polycystic ovary syndrome (PCOS) patients was influenced by metformin. In this study, most women with PCOS suffered from insulin resistance, hyperinsulinemia, and elevated serum IL-6 level (45).…”

PCOS and Pregnancy: Impact of Endocrine and Metabolic Factors

“…Metformin is a natural molecule (originally extracted and modifi ed from the French lilac Galega offi cinalis ), with insulin-lowering effects by improving insulin sensitivity and, in turn, decreases circulating androgen levels. A recent systematic review showed a signifi cant reduction of IL-6 by metformin in agreement with its role in improving insulin receptors damaged by low-grade infl ammation in overweight-obese women affected by PCOS [ 40 ].…”