Metformin exerts antifibrosis effect on human lens epithelial cells through transforming growth factor-β inhibition

To investigate the antifibrosis effect of metformin human lens epithelial cells (HLECs) in vitro. HLECs were isolated from single donor of anterior capsule and treated with culture media supplemented with various doses of metformin as 0.1mM, 0.5 mM and 1mM. While the media was treated with 2% FBS as control group, with the cells stained using TGF-β FITC conjugated antibody and α-SMA used to examine the antifibrosis effect. Data were analyzed using oneway ANOVA and posthoc test with significant level of p<0.05. TGF-β antibody expression levels decreased after the administration of metformin 0.1mM (6.96 × 10⁶ pixels ± 1.03 × 10⁶ pixels), metformin 0.5mM (5.35 × 10⁶ pixels ± 1.23 × 10⁶ pixels) and metformin 1mM (1.93 × 10⁶ pixels ± 0.94 × 10⁶ pixels). The Tukey HSD post hoc test showed a significant decrease in expression levels in the 0.5mM metformin group (p = 0.027) and 1mM metformin (p = 0.000) compared to 2% FBS control. The levels of a-SMA antibody expression decreased after the administration of metformin 0.1mM (4.49 × 10⁶ pixels ± 0.74 × 10⁶ pixels), 0.5mM (3.34 × 10⁶ pixels ± 0.47 × 10⁶ pixels) and 1mM (2.26 × 10⁶ pixels ± 0.55 × 10⁶ pixels) metformin. The Games-Howell post hoc test showed a significant decrease in expression levels between the control groups compared and the three treatment groups consisting of 0.1mM (p = 0.035), 0.5mM (p = 0.008) and 1 mM (p = 0.002) metformin with 2% FBS. Metformin tends to have antifibrotic effect on HLECs through TGF-β inhibition.