Effect of epigallocatechin-3-gallate on radiation-induced esophagitis of rabbit

Objective To analyze the effect of epigallocatechin-3-gallate (EGCG) in radiation induced esophagitis of model rabbit. Methods Thirty male New Zealand rabbits were randomly divided into EGCG group, saline group, blank group. The rabbits in EGCG and saline groups were irradiated with 6 MV X-rays. The blank group did not receive radiation. After irradiation, rabbits were given with 440 μmol/L EGCG or saline three times a day in continuous 5 days. The scores of pathological changes of esophagus were observed by optical microscope.The serum levels of interleukine-1 beta (IL-1β), interleukine-6 (IL-6), transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α) were detected by enzyme linked immunosorbent assay. The expression levels of 67KD laminin receptor (67LR) was detected by immunohistochemistry. Results After treatment, the scores of pathological changes of esophagus in blank group, saline group, EGCG group were 0, 3.9±1.10 and 2.80±0.92, respectively. At different time points after drug treatment, the levels of serum inflammatory factors among three groups were significantly different (F=23.66-236.32, P<0.05). The expressions of 67LR in esophageal tissue of 3 groups were also significantly different (F=585.38, P<0.05). Conclusions EGCG reduced radiation-induced esophagitis in rabbits by decreasing the levels of serum inflammatory factors, which may be related to the expression of 67LR protein. Key words: Radiation injury; Epigallocatechin-3-gallate; Protection