The In Vivo and In Vitro Effects of Terminalia bellirica (Gaertn.) Roxb. Fruit Extract on Testosterone-Induced Hair Loss

Can Plant Extracts Help Prevent Hair Loss or Promote Hair Growth? A Review Comparing Their Therapeutic Efficacies, Phytochemical Components, and Modulatory Targets

“…It is interesting to observe that male hormones reduced the viability of dermal papilla cells and that several plant extracts restored cell viability [66][67][68]. The camellia (Camellia japonica) extract promoted cell proliferation and alleviated the decline in cell viability caused by androgenic hormones [61,67].…”

“…Hair removal methods include shaving with clippers or applying a kind of hair-removing solution or product followed by wiping to remove [58]. Some previous studies have developed animal models that mimic hormonal hair loss conditions by topical application or subcutaneous injection of testosterone in mice [68,84] or that mimic menopause conditions by ovariectomy in female Sprague-Dawley rats [95]. The chronic restraint stress model has also been used in hair research [96].…”

“…The plant extract has been applied topically in many studies, but it has also been administered via subcutaneous injection [39,42] or oral feeding [68,95]. When applying a test substance topically, it is necessary to optimize the vehicle by considering the solubility of the drug, skin irritation, and skin absorption.…”

“…Test substances were administered once a day in most cases, yet there were also cases where they were administered twice a day or once every few days. Many studies used minoxidil as the positive control, while finasteride has also been used [68].…”

“…The entire period of test substance administration after hair removal varied depending on the study, from 2 weeks [68,82] to 7 weeks [43], and the measurement of hair growth often continued until the hairs in the hair removal area had grown to the length of the surrounding area. However, in a study that counted the number of hair follicles per unit skin area or hair shafts per follicle, the test substance was administered for 10 days [77] or 3 months [95].…”