Response of p53, capsase 3 and gadd45 genes in the rat lens to in vivo exposure to UV‐B radiation

Abstract

Abstract Purpose To study the transcriptional induction of p53, caspase 3 and gadd45 genes in the rat lens by in vivo exposure to double threshold UVR‐B around 300 nm. Methods Forty 6‐week‐old female albino Sprague‐Dawley rats were exposed to double threshold dose (8 kJ/m2) UVR (λmax = 300 nm) unilaterally for 15 minutes. The animals were sacrificed at 1, 5, 24 and 120 h following the exposure to UVR‐B. p53, caspase 3 and gadd45 mRNA expression of the lenses was analysed by quantitative RT‐PCR. Data were analysed using one‐way ANOVA. Results p53 is downregulated in exposed lenses in 1 h and 5 h groups and upregulated in 24 h and 120 h groups. Caspase 3 is downregulated in exposed lenses in 1, 5 and 24 h groups and upregulated in 120 h group. No difference in gadd45 mRNA expression between exposed and nonexposed lenses was found in all time intervals. Conclusion p53 mRNA increased expression precedes caspase 3 mRNA increased expression in the rat lens after in vivo UVR‐B exposure. UVR‐B exposure did not induce transcription of DNA damage repair gene gadd45 in the lens up to 120 h.