Objective To study the protective effect of vitamin C on UV-induced photoaged skin structure in rats and provide a basis for clinical medicine and health care.Methods Photoaging skin models were set up by chronic ultraviolet radiation in 24 SPF female Sprague-Dawley rats, irradiated twice weekly for 4 weeks.The rat photoaged skin was induced by exposure to a total dose of 123 J/cm2 UVA and 5 J/cm2 UVB for 4 weeks.Vitamin C was administered by gastric gavage in a dose of 50 mg/kg once daily for 30 days during the model development.We compared the pathological changes in the irradiated skin using HE, Masson’ s trichrome and Victoria blue B staining, and compared the ultrastructural changes by electron microscopy.Results Rat models with photoaged skin were developed successfully.The vitamin C group showed significant reduction of pathological severity including erythema, ulcers, epidermal cell proliferation, epidermal thickness, dermis vasodilation, inflammatory cell infiltration, fibroblast proliferation, endoplasmic reticulum dilatation, mitochondrial swelling and vacuolization, elastic fibers degeneration and focal accumulation, collagen fibers swelling with uneven thickness,compared with the rats of model group at the irradiation site.Conclusions Vitamin C is effective in reducing the structural damage of UV-induced photoaged skin in rats.

Laccases (benzenediol: oxygen oxidoreductases; EC 1.10.3.2) are copper-containing polyphenol oxidases that can oxidize a wide range of aromatic compounds, concomitantly with the transfer of four electrons and the reduction of molecular oxygen to water. The progress on the research of laccases structure and function is reviewed. Their three-dimensional structures and catalytic mechanism, as well as their applications in different fields are emphasized.
Catalysis ; Hydrocarbons, Aromatic ; isolation & purification ; metabolism ; Laccase ; chemistry ; metabolism ; Oxidation-Reduction