Delayed Hair Cycle in Mnd2 Mutant Mice Lacking HtrA2 Serine Protease Activity

The study on mnd2 mutant mice lacking HtrA2 serine protease activity shows a delayed hair cycle due to a prolonged telogen phase, preventing normal transition to the anagen phase. This delay is associated with a 2-fold reduction in subcutaneous tissue thickness and impaired adipocyte growth, as confirmed by histological and molecular analyses. Elevated PPARγ expression in mnd2 mice indicates delayed adipocyte differentiation. These findings suggest that HtrA2 activity is crucial for normal hair cycle progression by regulating adipogenesis, making it a potential therapeutic target for hair loss and related conditions.