L-Cystine-Containing Hair-Growth Formulation Supports Protection, Viability, and Proliferation of Keratinocytes

The study from August 2020 examined the effects of a hair-growth formulation containing L-cystine, thiamine, calcium D-pantothenate, and folic acid on human hair follicle keratinocytes (HHFKs). It found that this combination increased HHFKs' metabolic activity, proliferation, and DNA synthesis, suggesting improved cell viability and protection against oxidative stress. L-cystine was particularly important for oxidative stress protection. The combination of all compounds was necessary for the maximal effect on cell proliferation. The study, which did not specify the number of participants or samples, was supported by Merz Pharmaceuticals GmbH, with some authors affiliated with the company. It concluded that the formulation could be beneficial for hair growth and protection against stress factors, potentially aiding in the treatment of hair loss conditions like diffuse telogen effluvium.