Fig. 3

Metformin suppresses splenic Th17 cell populations and enhances Treg populations. a Eleven-week-old mice were orally administered vehicle or 50 mg/kg metformin daily for 9 weeks (n = 5 per group). The spleens were removed and reacted with antibodies against CD4, IL-17, p-STAT3 (Y705), CD25 or Foxp3. CD4⁺IL-17⁺p-STAT3 (Y705)⁺ (Th17) cells and CD4⁺CD25⁺Foxp3⁺ (Treg) cells were analyzed by confocal laser microscopy (original magnification, × 200; insets, × 400). b Splenic IL-6, TNF-α, IL-17, and STAT3 mRNA levels in vehicle- and metformin-administered mice, as determined by real-time PCR. Data are means ± SEMs. Data are representative of three independent experiments (*p < 0.05, **p < 0.01, ***p < 0.001)