Abstract
Epigallocatechin gallate (EGCG) has the effect to protect skin from ultraviolet B (UVB) induced damages, but it is unstable under ambient conditions, being susceptible to become brown in color. Gallocatechin gallate (GCG), an epimer counterpart of EGCG, is more stable chemically than EGCG. The potential effects of GCG against UVB-induced skin damages has not been available. The objective of this study was to investigate the protective effects of GCG against UVB-induced skin photodamages. GCG was topically applied on the skin of hairless mice at three dosage levels (LL, 12.5 mg/mL; ML 25 mg/mL; HL, 50 mg/mL), with EGCG and a commercially available baby sunscreen lotion SPF50 PA+++ as control. The mice were then irradiated by UVB (fluence rate 1.7 µmol/m2 s) for 45 min. The treatments were carried out once a day for 6 consecutive days. Skin measurements and histological studies were performed at the end of experiment. The results show that GCG treatments at ML and HL levels inhibited the increase in levels of skin oil and pigmentation induced by UVB irradiation, and improved the skin elasticity and collagen fibers. GCG at ML and HL levels inhibited the formation of melanosomes and aberrations in mitochondria of UVB-irradiated skin in hairless mice. It is concluded that GCG protected skin from UVB-induced photodamages by improving skin elasticity and collagen fibers, and inhibiting aberrations in mitochondria and formation of melanosomes.
Highlights
Skin is the body’s first line of defense and it acts as a shield to protect the body from environmental stress
Epigallocatechin gallate (EGCG) was proved to have protective effects against ultraviolet B (UVB)-induced skin damages[19], but it is susceptible to illumination, oxygen and high temperature, resulting in browning in color, which is undesirable in cosmetic products[20]
Testing results of skin quality indicators by skin analyzer show that compared to the blank control (BC), UVB irradiation (NC, negative control) induced an increase in levels of skin oil, moisture and pigmentation, accompanying with a decrease in elasticity and collagen fibers in hairless mice skin
Summary
Skin is the body’s first line of defense and it acts as a shield to protect the body from environmental stress. It consists of epidermis, dermis and the subcutaneous tissue. It is interesting to search for natural sunscreen agents to protect skin from photodamages induced by UVB irradiation. Gallocatechin gallate (GCG) is the spatial isomer of EGCG13 Both EGCG and GCG have strong radical-scavenging activity. EGCG was proved to have protective effects against UVB-induced skin damages[19], but it is susceptible to illumination, oxygen and high temperature, resulting in browning in color, which is undesirable in cosmetic products[20]. The protective effect of GCG against UVB-induced skin damages has not been available. Of GCG on skin of hairless mice, so as to provide a useful information for developing sunscreen agents against UVB-induced photodamages or photoaging using GCG as ingredient
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
