ABSTRACT
Objective To investigate the dynamic changes in intestinal alpha-defensin-5 (RD-5),beta-defensin-2 (BD-2) mRNA after acute liver failure(ALF),and to explore their role in ALF.Methods A total of 60 C57BL5 mice were divided into 4 groups by means of random number table method:normal control group,ALF group,E.coli via gavage group and ALF + E.coli via gavage group.Intraperitoneal injection of D-galactosamine (500 mg/kg) and lipopolysaccharide(10 μg/kg) to make the model,in addition,ALF mice were fed with E.coli,and the observation time was 6 hours,12 hours,and 24 hours after modeling,and each time point had 6 specimens.Real-time PCR was used to test the RD-5 mRNA and BD-2 mRNA levels in the ileum tissue.Results The levels of RD-5 and BD-2 showed dynamic change in the experiment of ALF.Compared with the levels of RD-5 and BD-2(11.25 ±0.74,23.86 ±0.39) of the normal control group,the levels of RD-5 and BD-2 in ALF group and E.coli via gavage group increased at 6 hours after modeling(14.19 ±0.39,26.79 ± 0.36 and 12.57 ± 0.68,26.45 ± 0.85),and the differences were significant(all P＜0.05);at 12 hours after modeling,the RD-5 and BD-2 reached to the maximum concentration(15.76 ±0.33,29.10 ± 0.61 and 12.90 ± 0.96,27.42 ± 0.71),and the differences were statistically signi-ficant (all P ＜ 0.05).The degree of elevation of BD-2 was higher than RD-5.Later,they gradually declined.Conclusions RD-5 and BD-2 may play an important role in the pathogenesis of intestinal endotoxemia in experimental ALF.
ABSTRACT
DNA methylation is the best studied of the epigenetic changes that influence the gene expression,and changes in genomic methylation patterns have been observed in many cancer cell lines.Nutrients as methyl donors play essential roles in DNA methylation and may modify cancer risk.This review,with an emphasis on the relationship between nutrition,DNA methylation and cancer,firstly defines methylation with a description of its correlated mechanism,then approaches the molecular mechanism of cancer initiation and development at the methylation level,and lastly summarizes the mechanism underlying the effect of methylation-related nutrients on the process of cancer initiation and development at the molecular level.It also offers some suggestions on cancer prevention at the group nutrition level.