Pre-clinical evidences of Pyrostegia venusta in the treatment of vitiligo

Abstract

Ethnopharmacological relevance: Leaves of Pyrostegia venusta are popularly used to treat vitiligo; however, none in vivo study showed its ability.

Aim of the study: The overall objective of the present study was to evaluate the antiinflammatory and hyperpigmentant activities of hydroethanolic (HE) extract of leaves from P. venusta in animal models of vitiligo induced by croton oil and monobenzone.

Materials and methods: The antiinflamatory and antioxidative effects of topical and oral administration of HE extract of P. venusta were evaluated in Swiss mice on edema model induced by croton oil, and further the N-acetyl-b-d-glucosaminidase (NAG) activity, cell infiltration, and cytokine and reactive species oxygen (ROS) levels. The involvement on mice pigmentation, cell infiltration and cytokine levels were evaluated on vitiligo model induced by monobenzone in C56BL/6 mice.

Results: HE of P. venusta by gavage (300 mg/kg) reduced NAG activity in 32.5 ± 5% on mouse ear edema induced by croton oil. Similarly, cell infiltration was lower (42.3 ± 5.9%) when compared to control group, as well as interleukin-1β (IL-1β), interleukin (IL-6) and tumor necrosis factor-α (TNF-α) levels, in 44.1 ± 9.7%, 71.9 ± 22.2% and to basal levels, respectively. Topical treatment with HE of P. venusta (10%) diminished cell infiltration (67.7 ± 7.1%) and ROS levels (total reduction). P. venusta either by gavage (300 mg/Kg) or topically (10%) increased epidermal melanin level (116.5 ± 13% and 100 ± 16.9%, respectively), diminished dermal depigmentation (36.0 ± 6.7% and 38.2 ± 6.2%, respectively), as well as tissue TNF-α levels (68.2 ± 11.6% and 99.2 ± 12.1%, respectively) and cell infiltration (basal levels and 94.3 ± 9.17%, respectively). However, only topical treatment with HE of P. venusta altered melanin specific marker in hair follicles.

Conclusions: For the first time these data show that topical and oral administrations of P. venusta have significant antiinflammatory and hyperpigmentant effects, demonstrating different topical and systemic effects through two animal models. Together these models are capable to mimic several features founded in vitiligo, and the results support the ethnopharmacological use of P. venusta.

Keywords: Croton oil; Melanogenesis; Monobenzone; Pyrostegia venusta; Vitiligo.