The Anti-Fibrotic Effects of IFN-γ on TGF-β1-Treated Endometrial Stromal Cells

Background: Endometrial fibrosis represents a distinctive pathological feature of diverse gynecological disorders, marked by the abnormal trans-differentiation of endometrial stromal cells (ESCs) and elevated deposition of extracellular matrix (ECM). Transforming growth factor-beta1 (TGF-β1) emerges as an essential driver of fibrogenesis. The present investigation sought to elucidate the regulatory pathways of Interferon-γ (IFN-γ) in driving fibrotic changes mediated by TGF-β1 within human ESCs populations. Methods: A TGF-β1-induced in vitro ESCs fibrosis model was established. ESCs were subjected to various concentrations and time durations of TGF-β1 stimulation. The fibroproteins α-smooth muscle actin (α-SMA), collagen type I alpha 1 (COL1A1), and Vimentin (VIM) were evaluated through a combination of quantitative reverse transcription-polymerase chain reaction (RT-qPCR), Western blotting, and immunofluorescent (IF) staining to assess cell fibrogenesis. IFN-γ pretreatment and intervention groups were designed to evaluate its inhibitory effects on fibrosis, with an emphasis on the TGF-β1/Smad signaling network. Results: TGF-β1 strongly induced ESCs to undergo fibrotic changes, leading to the elevation of COL1A1 and α-SMA expressions while simultaneously reducing Vimentin levels. This effect was demonstrated in both dose and timing. IFN-γ notably suppressed the production of fibrotic markers induced by TGF-β1, mitigated the reduction in Vimentin expression, and effectively dampened the phosphorylation of p-Smad3 levels. Conclusion: IFN-γ inhibits TGF-β1- mediated fibrosis in ESCs by targeting the TGF-β1/Smad signaling pathway, providing new insights into the mechanism of endometrial fibrosis and potential theoretical support for targeted therapy of related diseases.