Chronic Restraint Stress Inhibits Hair Growth via Substance P Mediated by Reactive Oxygen Species in Mice

The study examined the impact of chronic restraint stress (CRS) on hair growth in mice, focusing on the role of substance P (SP) and reactive oxygen species (ROS). It found that CRS inhibited hair growth by prolonging the telogen stage and delaying the anagen and catagen stages, associated with increased oxidative stress and decreased antioxidant enzyme activities. The study involved 9 mice per group and demonstrated that CRS induced psychoemotional stress, evidenced by inhibited body weight gain and increased plasma corticosterone levels. The use of an SP receptor antagonist and the antioxidant Tempol normalized the hair cycle and reduced oxidative stress, suggesting that the SP-NK1-mast cell-ROS pathway mediated these effects and highlighting the potential of antioxidants as a treatment for stress-induced hair loss.