Ageratum conyzoides Extract Promotes Hair Shaft Thickness Accompanied by Increased Growth Factor Levels and Enhanced Antioxidant Status in C57BL/6 Mice

Hair loss results from disrupted hair follicle cycling, age-related hormonal imbalance, and oxidative stress, and remains a significant psychological burden for which safe, evidence-based interventions are limited. This study evaluated the effects of a standardized Ageratum conyzoides extract (ACE) on hair follicle growth, hair shaft thickness, and hair shaft morphology in C57BL/6 mice. Mice received oral ACE (10, 20, or 50 mg/kg) for 21 days, and hair regrowth, follicle and shaft characteristics, antioxidant-related responses, serum IGF-1 and VEGF levels, and cuticle morphology were evaluated. ACE accelerated hair regrowth at 20 and 50 mg/kg, increased hair shaft thickness and follicle diameter across all tested doses, and increased follicle number at 20 and 50 mg/kg compared with vehicle, with effects most consistent at 50 mg/kg. ACE upregulated Nrf2, HO-1, SOD2, and GPx1 expression in dorsal skin, increased serum IGF-1 and VEGF levels and dorsal skin superoxide dismutase (SOD) activity, and reduced dorsal skin malondialdehyde (MDA). Scanning electron microscopy revealed reduced hair shaft cuticle damage scores in ACE-treated mice, indicating improved cuticle surface integrity. These findings indicate that ACE promotes hair follicle growth and increases hair shaft thickness, accompanied by increased growth factor levels and enhanced antioxidant status, thereby extending prior findings and supporting further investigation of ACE for hair health.