miR-101-3p suppresses proliferation of orbital fibroblasts by targeting pentraxin-3 in thyroid eye disease.

Background: Excessive proliferation of orbital fibroblasts (OFs) is an essential factor in the pathogenesis of thyroid eye disease (TED). While existing evidence indicates that various microRNAs (miRNAs) significantly contribute to TED development, the precise function and targets of miR-101-3p in TED pathogenesis remain unknown. This research aims to elucidate the effects of miR-101-3p on TED-OFs and identify its potential targets. Methods: Orbital adipose tissues were harvested from both TED patients and healthy controls to culture their fibroblasts. MiR-101-3p mimic or mimic negative control (mimic NC) was transfected into OFs from TED patients, with untreated OFs serving as an additional blank control group. Cell proliferation was assessed using cell counting kit-8 (CCK-8) assay, Ki-67 immunofluorescence staining, and the EdU assay, while apoptosis was evaluated Results: The results demonstrated a significant downregulation of miR-101-3p in fibroblasts and TED orbital adipose tissues. Transfection with the miR-101-3p mimic upregulated miR-101-3p levels, significantly reducing OFs proliferation without affecting apoptosis. Overexpression of miR-101-3p led to the downregulation of PTX3 in OFs. The dual-luciferase assay validated miR-101-3p binding to PTX3's 3'UTR, thereby repressing its expression. Moreover, overexpression of PTX3 partially rescued the miR-101-3p mimic's inhibitory effect on TED-OFs proliferation. Conclusion: Our findings illustrate miR-101-3p's role in targeting PTX3 to regulate TED-OFs proliferation, providing novel insights into the pathological mechanisms underlying TED development.