Effects of Poly-L-Lactic Acid on Adipogenesis and Collagen Gene Expression in Cultured Adipocytes Irradiated with Ultraviolet B Rays.

BACKGROUND: Poly-L-lactic acid (PLLA), a synthetic, biocompatible, and biodegradable polymer, has been safely used in several clinical applications. Recently, PLLA has been widely used in the field of dermatology to treat wrinkles in aging skin. Reportedly, PLLA directly acts on dermal fibroblasts causing a significant increase in the expression of type I collagen. However, little is known about the effect of PLLA on adipocytes. OBJECTIVE: This study aimed to analyze the effect of PLLA on adipocytes and examine its potential in treating deep wrinkles engendered by the loss of subcutaneous fat because of aging and photoaging. METHODS: To elucidate the effect of PLLA on skin photoaging, cultured 3T3-L1 adipocytes were irradiated with ultraviolet B (UVB) rays. Oil red O staining was used to detect lipid accumulation in the adipocytes. Real-time quantitative polymerase chain reaction and Western blotting were performed to detect types IV and VI collagen mRNA and protein levels, respectively, under different conditions. RESULTS: The differentiation of 3T3-L1 cells enhanced adipogenesis and the expression of types IV and VI collagens, both of which were inhibited by UVB irradiation. Following this irradiation, PLLA stimulated adipogenesis and the expression of types IV and VI collagens. CONCLUSION: PLLA may provide the beneficial effect on adipocytes from the aspect of adipogenesis and collagen expression in the subcutaneous adipose tissues.