ABSTRACT
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.
Subject(s)
DNA Damage/drug effects , Epidermis/drug effects , Epidermis/radiation effects , Flavonoids/pharmacology , Plant Extracts/pharmacology , Scutellaria baicalensis , Ultraviolet Rays/adverse effects , Administration, Cutaneous , Analysis of Variance , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , DNA/analysis , Epidermis/metabolism , Epidermis/physiology , Female , Mice , Mice, Inbred BALB C , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Pyrimidine Dimers/metabolism , RNA, Messenger/analysis , Tumor Suppressor Protein p53/metabolism , bcl-2-Associated X Protein/genetics , bcl-2-Associated X Protein/metabolismABSTRACT
Field avian infectious bronchitis virus (IBV) designated as JS/9 5/03, which was isolated from Jiangsu province of china, was cultivated in chicken emb ryo. It's single strain RNA was extracted from purified virus and worked as temp late of reverse transcription polymerase chain reaction (RT-PCR), a pair of pri mer designed according to megalign results of published IBV sequences in Genbank was used to amplify the neucleocapsid gene, the RT-PCR product was sequenced d irectly. Sequence analysis revealed that the sequence of JS/95/03 is most homolo gized with that of M41 strain.
