OBJECTIVETo investigate the influence of genetic polymorphism in NF-E2-related factor-2 (nrf2) gene promoter locus at 336 in alcoholic liver disease (ALD) with Vibrio vulnificus (VV) sepsis.

METHODSThrough the simple random sampling method, C57B6 male mice were divided into normal feeding group (group A, 10 mice), alcoholic liver disease group (group B, 10 mice), normal feeding group infected with VV through intraperitoneal injection (group C, 8 mice), alcoholic liver disease group infected with VV (group D, 110 mice). Through gene sequencing method, nrf2 gene promoter 336 polymorphism in D group was analyzed and grouped into: non-mutation group (336T) (group D1, 7 mice) and mutation group (336C) (group D2, 10 mice). Through RT-PCR, Western-blotting and ELISA method, expressions of nrf2, tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), high mobility group protein 1 (HMGB(1)) gene and protein of liver were measured. The pathological changes in liver were recorded with light microscope.

RESULTSAfter infected with VV for 48 hours for A, B, C, D1, D2 group, the expression medians of nrf2 mRNA in liver were 0.115, 0.173, 0.211, 0.764, 0.352, respectively (χ(2) = 40.64, P < 0.05), the expression medians of IL-10 mRNA in liver were 0.338, 0.637, 1.002, 1.825, 1.403, respectively (χ(2) = 41.05, P < 0.05), the expression medians of TNF-α mRNA in liver were 0.140, 0.254, 0.372, 0.399, 0.699, respectively (χ(2) = 38.16, P < 0.05), the expression medians of HMGB(1) mRNA in liver were 0.230, 0.410, 0.668, 0.508, 1.021, respectively (χ(2) = 31.45, P < 0.05). After infected with VV 48 hours for mice in A, B, C, D1, D2 group, the expression medians of nrf2 protein in liver were 0.908, 1.461, 2.061, 3.982, 2.243, respectively (χ(2) = 33.72, P < 0.05), the expression medians of IL-10 protein in liver were 13.97, 22.54, 30.14, 57.98, 41.53, respectively (χ(2) = 37.31, P < 0.05), the expression medians of TNF-α protein in liver were 114.07, 142.94, 175.44, 174.60, 266.11, respectively (χ(2) = 32.29, P < 0.05), the expression medians of HMGB(1) protein in liver were 2.01, 6.05, 9.62, 6.24, 12.89, respectively (χ(2) = 36.94, P < 0.05). Compared with group A, there were large amount of fat drops, fatty changes in group B, inflammatory cell infiltration, disorder of hepatic cell in group C, and extension of hepatic duct and vein, edema of liver cells and disorder of hepatic cells in group D.

CONCLUSIONThe nrf2 gene promoter of T336C mutation in C57B6 mouse of ALD can significantly decrease the expression of nrf2, and intensify organ inflammation and damage when they were infected by VV.