title: Caffeic Acid Inhibits UVB-induced Inflammation and Photocarcinogenesis Through Activation of Peroxisome Proliferator-activated Receptor-γ in Mouse Skin.
abstract: In this study, the effect of caffeic acid (CA) on both acute and chronic UVB-irradiation-induced inflammation and photocarcinogenesis was investigated in Swiss albino mice. Animals were exposed to 180 mJ cm(-2) of UVB once daily for 10 consecutive days and thrice weekly for 30 weeks for acute and chronic study respectively. UVB exposure for 10 consecutive days showed edema formation, increased lipid peroxidation and decreased antioxidant status with activation of inflammatory molecules such as TNF-α, IL-6, COX-2 and NF-κB. However, CA (15 mg per kg.b.wt.) administration before each UVB exposure decreased lipid peroxidation, inflammatory markers expression and enhanced antioxidant status probably through the activation of peroxisome proliferator-activated receptors (PPARγ) in the mice skin. PPARγ is considered a potential target for photochemoprevention because it inhibits UVB-mediated inflammatory responses. In this study, UVB exposure for 30 weeks caused squamous cell carcinoma and upregulation of iNOS, VEGF and TGF-β and downregulation of p53 and tumor incidence in the mice skin. Both topical (CAT) and intraperitoneal (CAIP) treatment before each UVB exposure downregulates iNOS, VEGF, TGF-β, upregulates p53 and reduces tumors multiplicity in the mice skin. Thus, CA offers protection against UVB-induced photocarcinogenesis probably through activation of anti-inflammatory transcription factor PPARγ in the mice.
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Agilan
authors: A
authors: Balupillai
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Rajendra N
authors: RN
authors: Prasad
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Karthikeyan
authors: K
authors: Ramasamy
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Ganesan
authors: G
authors: Muthusamy
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Mohana
authors: M
authors: Shanmugham
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Kanimozhi
authors: K
authors: Govindasamy
authors: Department of Biochemistry and Biotechnology, Annamalai University, Annamalainagar, Tamil Nadu, India.
authors: Srithar
authors: S
authors: Gunaseelan
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D002109:Caffeic Acids / Q000494:pharmacology*; D063646:Carcinogenesis / Q000187:drug effects*; D005260:Female; D007249:Inflammation; D051379:Mice; D008812:Mice, Hairless; D047495:PPAR gamma / Q000378:metabolism*; D012867:Skin / Q000187:drug effects*; D015533:Transcriptional Activation / Q000187:drug effects*; D014466:Ultraviolet Rays
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D002109:Caffeic Acids; D047495:PPAR gamma; C040048:caffeic acid