Abstract
Androgens are emerging as important regulators of connective tissue remodeling, but current knowledge about their role in human fascia is still limited. This study examined the expression of the androgen receptor (AR) in human deep fascia and investigated the effects of dihydrotestosterone (DHT) on collagen production by fascial fibroblasts. Fascia lata and thoracolumbar fascia samples were collected from four adult donors (two male and two female). AR expression was assessed by immunohistochemistry and immunocytochemistry. Fascial fibroblasts were treated in vitro for 24 h with DHT at concentrations reflecting physiological levels: 0.4 ng/mL (female), 4 ng/mL (male average), and 10 ng/mL (high male dose). Collagen content was quantified using Picrosirius Red staining, and collagen I and III were evaluated using immunocytochemistry and image analysis, and were compared to an untreated control group. AR was detected in all samples. Low-dose DHT (0.4 ng/mL) significantly increased collagen I (4.80 ± 1.75%) and decreased collagen III (3.32 ± 0.46%) compared to controls (2.09 ± 0.91% and 10.46 ± 0.53%, respectively; p < 0.05). Higher DHT doses induced smaller or no significant changes in collagen subtype expression (e.g., 10 ng/mL: 2.03 ± 0.81% for collagen I, 8.49 ± 1.85% for collagen III). The results demonstrated that human fascia is hormonally responsive via AR, with DHT modulating matrix composition in a dose-dependent manner. The distinct effects at male and female levels may help explain gender differences in fascial stiffness and pain.