The influence of KGF on CTGF and Bcl-2 gene in duodenal tissue induced by radiation

Abstract

Objective To observe the effects of keratinocyte growth factor (KGF) on connective tissue growth factor (CTGF) and B-cell lymphoma 2 (Bcl-2) gene expressions in radiation-induced duodenal tissue, and to investigate the molecular mechanism of KGF in radiation-induced intestinal injuries. Methods Using the stochastic indicator method, Kunming mice were randomly divided into control, radiation, and treatment groups, each with 10 mice. The control group did not undergo the radiation process. The radiation group and treatment group underwent abdominal cavity irradiation with a dose rate of 0.678 Gy/min and an absorbed dose of 8 Gy with γ-ray. For 2 d before and 3 d after irradiation, KGF with a dose of 6 mg/kg was administered via intraperitoneal injection to the KGF treatment group. All mice were executed 15 d after irradiation, after which the duodenal tissue pathological slices were captured. Quantitative polymerase chain reaction was used to detect the KGF, CTGF, and Bcl-2 gene relative expressions in duodenal tissue. The measurement data were ±s. The two groups were compared using independent samples t-test, and P<0.05 indicated that the difference was statistically significant. Results For the control group, the duodenum intestinal villus and crypt structure were complete. For the radiation group, villi atrophy was shorter or fell off, and parts of the crypt and villi were observed in few apoptotic cells. For the treatment group, the organizational structure was complete, and a small amount of crypt can be seen in apoptotic cells. Compared with the control group, KGF, CTGF, and Bcl-2 gene expressions significantly increased after irradiation (t=-125.55, -6.55, -6.69, all P<0.05) . Compared with the radiation group, the gene expression of CTGF was significantly down-regulated (t=4.89, P<0.05) , and that of Bcl-2 was significantly up-regulated in the treatment group (t=-20.96, P<0.05) . Conclusions The model of acute radioactive duodenitis was successfully established. KGF repair damage was caused by ionizing radiation through down-regulating CTGF gene, and reduce apoptosis was caused by the regulation of the expression levels of the apoptosis-related Bcl-2 gene. Key words: Radiation, ionizing; Gene, bcl-2; Connective tissue growth factor; Keratinocyte growth factor; Radiation enteritis