【Animal modeling】-Defensive effects of curcumin and tea polyphenols on UVB-induced acute light damage in hairless rats at different times

  Objective: To investigate the protective effects of curcumin and tea polyphenols on UVB-induced acute light damage in hairless rats at different times.

  METHODS: Thirty-six clean-grade hairless rats were randomly divided into control group and drug group (0 s, 30 s, 60 s, 120 s, 240 s); 2 mice in each group. Curcumin or tea polyphenols were smeared on the back of hairless mice 30 minutes before irradiation, the irradiation distance was 15 cm, and UVB with 3 times the minimum erythema dose (MED) of about 200-540 mJ/cm2 was used to irradiate each group respectively, and the skin tissue was collected. , made into paraffin sections and observed by light microscope.

  RESULTS: The skin of the hairless mice in the control group had different degrees of scales, and scattered lymphocytes were found between the collagens. At 120 s and 240 s, collagen red staining, disordered arrangement, and homogenization appeared. The infiltration of inflammatory cells in the dermis of hairless mice in the drug group was reduced, and the collagen damage was improved.

  Conclusion: Topical application of curcumin and tea polyphenols can protect against UVB-induced acute photodamage of hairless rat skin by reducing inflammatory cell infiltration and reducing collagen damage.