Hypericin and Berberine Synergistically Promote Hair Follicle Elongation in Organoids via Oxytocin Signaling

Hair loss, or alopecia, affects millions globally, often leading to significant psychological distress. While oxytocin has been identified as a hormone that promotes hair growth, its large molecular weight and poor skin permeability limit its direct topical application. This creates a critical gap for developing small-molecule alternatives that can mimic or enhance oxytocin's effects on hair follicles. Understanding the specific mechanisms, such as oxytocin receptor expression and activation, is key to identifying viable therapeutic compounds.

Researchers comprehensively screened for molecules that could either increase oxytocin receptor expression or act as oxytocin receptor agonists. This involved in vitro 2D culture of dermal papilla cells and in silico screening based on binding affinity. They identified hypericin as a compound enhancing oxytocin receptor expression and berberine as an oxytocin receptor agonist. The additive effects of these compounds on hair growth promotion were then validated using hair follicle organoid-based assays, which simulate the complex structure and function of natural hair follicles.

The study successfully identified two small molecules with distinct but complementary actions on the oxytocin pathway. Hypericin was found to significantly enhance oxytocin receptor expression in dermal papilla cells, suggesting it primes hair follicles to be more responsive to oxytocin signaling. Concurrently, berberine was identified as a direct oxytocin receptor agonist, capable of activating the receptor. The most compelling finding emerged from the hair follicle organoid-based assays:

The additive effects of hypericin and berberine on hair growth promotion were clearly demonstrated, leading to enhanced elongation of hair peg-like sprouting. This synergistic action suggests a dual-pronged approach where one compound increases receptor availability while the other directly stimulates it, mimicking the natural oxytocin effect on hair follicle growth.