Related Experiment Video
Updated: Jun 28, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Effects of Coccoloba uvifera L. on UV-stimulated melanocytes
Jéssica Eleonora Pedroso Sanches Silveira1, Maria del Carmen Velazquez Pereda, Samara Eberlin
1Department of Pharmacology, São Paulo State University, Botucatu, Brazil.
Background:
Exposure to ultraviolet (UV) radiation induces generation of reactive oxygen species, production of proinflammatory cytokines and melanocyte-stimulating hormone (MSH) as well as increase in tyrosinase activity. The potential photoprotective effects of Coccoloba uvifera extract (CUE) were evaluated in UV-stimulated melanocytes.
Methods:
Human epidermal melanocytes were used as an in vitro model to evaluate the effects of CUE on the production interleukin-1alpha (IL-1alpha), tumor necrosis factor alpha (TNF-alpha), and alpha-MSH under basal and UV-stimulated conditions. Antioxidant and anti-tyrosinase activities were also evaluated in membrane lipid peroxidation and mushroom tyrosinase assay, respectively.
Results:
Coccoloba uvifera L. showed antioxidant and anti-tyrosinase activities and also inhibited the production of IL-1alpha, TNF-alpha and alpha-MSH in melanocytes subjected to UV radiation (P<0.01). Moreover, CUE inhibited the activity of tyrosine kinase in cell culture under basal and UV radiation conditions (P<0.001), corroborating the findings of the mushroom tyrosinase assay.
Conclusion:
This study supports the photoprotective potential of CUE.
Related Concept Videos
Pigmentation
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
Skin Cancer
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
Mutations
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Role of Skin in Vitamin D Synthesis
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin D3(cholecalciferol).
Changes in Skin Color: Clinical Perspectives
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...

