The effect of Medicago sativa extract and light on skin hypopigmentation disorders in C57/BL6 mice

Abstract

Vitiligo is a common depigmentation skin disease that affects the quality of life in many patients. This study aims to investigate the effect of Medicago sativa methanol extract on the treatment of skin hypopigmentation disorders. Antioxidant activity and phytochemical constituents of the extract were determined using DDPH assay, Folin-Ciocalteu, AlCl3 and HPLC-MS/MS analysis. Oil in water (o/w) creams were prepared to contain the methanolic extract, and applied to hydroquinone-induced depigmentation in vivo model and further challenged in combination with UVA light exposure. Skin and hair colors were visually scored and evaluated at different time intervals, and histopathological examinations of skin layers and hair follicles were performed. Results showed total phenolic content of 187.70 mg/g, equivalent to gallic acid, and total flavonoid content of 21.97 mg/g, equivalent to quercetin. Most interestingly, the extract showed an antioxidant percent inhibition activity of 71%. Moreover, the HPLC-MS/MS detection revealed the presence of 18 compounds including P-coumaric acid and antioxidants flavonoids, of those are 7 compounds not previously detected in this species. The in vivo study showed a remarkable skin and hair pigmentation effect on plant extract treated groups, compared to the reference, placebo and control groups. Histopathological examinations showed the growth of coloured hair follicles in the dermis and epidermis layers of the extract treated mice. In conclusion, the study suggests the use of M. sativa extract in enhancing the pigmentation process in hypopigmented skin and hair if combined with UVA light. Therefore, M. sativa extract can be considered a potential treatment for vitiligo.

Plants as Modulators of Melanogenesis: Role of Extracts, Pure Compounds and Patented Compositions in Therapy of Pigmentation Disorders

“…Data show that 200 μL of Nymphaea nouchali extract, applied on UVB-irradiated HRM-2 hairless mice at a concentration 100 µg/mL to a 3 cm × 3 cm designated area on the dorsal skin for 4 weeks exhibit antimelanogenic effects [ 107 ]. Medicago sativa extract used at 10% or 20% concentrations and administered to dorsal region of C57/BL6 mice for 4 weeks exhibit a remarkable skin and hair pigmentation [ 108 ]. A study conducted by Choi et al on UVB-irradiated brown guinea pig skin models revealed that Cyrtomium fortunei used at 3% concentration on back area and administered for 6 weeks exhibited depigmenting properties [ 109 ].…”