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Updated: Jul 2, 2026

Studying Chronic Exposure of Mice to Ultraviolet B Radiation
Published on: August 19, 2025
Protective effect of the Baicalin against DNA damage induced by ultraviolet B irradiation to mouse epidermis
Zhou Bing-Rong1, Jin Song-Liang, Chen Xiao-E
1Department of Dermatology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Purpose:
To investigate whether topical application of Baicalin affords protecting Balb/C mice epidermis from ultraviolet (UV)B-induced DNA damage and its underlying mechanisms.
Methods:
A DNA damage model of UVB irradiation-induced mice epidermis was established. The immunohistochemical staining, Southwestern dot-blotting were used for cyclobutane pyrimidine dimers (CPDs) detection; Western blotting was used for p53 detection; reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA level of Bcl-2 and Bax; terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was used to detect apoptotic cells.
Results:
Topical application of Baicalin on Balb/C mice skin significantly decreased the amount of epidermal CPDs 1, 24 and 48 h after 180 mJ/cm(2) of UVB irradiation as compared with untreated mice. UVB-induced apoptosis was less pronounced in Baicalin-treated mice epidermis, which was accompanied by less p53 accumulation and higher Bcl-2/Bax ratio compared with that of untreated mice.
Conclusion:
Taken together, these results suggest that topical Baicalin application mitigates DNA photo-damage. Baicalin is therefore a promising protective substance against UVB radiation.
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