Study On NF-κB Interaction Mechanisms Of Acute Alcoholic Liver Injure In Rats Intervened By PDTC

Objectives:This study establishes animal model of acute alcoholic liver injure by alcohol gavage in short term while giving intraperitoneal injection of NF-kB blocker PDTC, thus to explore NF-kB interaction mechanisms of acute alcoholic liver injure in rats intervened by PDTC and influence of PDTC on inflammatory mediator expression.Methodology:1.Divide Wistar rats (clean grade) into three groups, model group, PDTC intervention group and control group. For model group, give them gavage twice per day for 14 days by 55% alcohol 8g/kg.d, and began to intraperitoneal inject normal saline since the third day; for PDTC intervention group, intraperitoneal inject PDTC 30 minutes before each time of gavage from the third day on with the dosage of 50mg/kg.d, and other operations to PDTC intervention group are the same with model group; for control group, give gavage and intraperitoneal injection with the same amount of normal saline. Rats were sacrificed 12 hours later than last time of gavage and intraperitoneal injection on the seventh and fourteenth day, collect blood samples from the heart and separate the serum, get and fix hepatic tissues with 10% neutral formalin immediately after blood collecting.2.Detect serum ALT and AST value by Automatic biochemical analyzer and detect NF-kB and TNF-αlevel in serum by enzyme linked immunosorbent assay (ELISA). Hepatic tissues are embedded by normal paraffin and cut into slices for HE and immunohistochemical stains (SABC Method), and observe pathologic changes and NF-kB and TNF-αexpression and distribution in hepatic tissues. Results:1.Comparison on ALT and AST Value of Rats Serum:Comparing model group to control group and intervention group to model group on the seventh and fourteenth day of experiment, ALT value (P<0.01) and AST value (P <0.01) in serum had changed a lot; and comparing the seventh day and the fourteenth day of model group, both of its serum ALT and AST value increased sharply(P <0.01).2.Pathologic Examination:HE staining results:control group shows normal liver lobule structure on the seventh and fourteenth day; for model group, its hepatic cells began to swell since the seventh day, fatty degeneration with inequality size appeared in hepatic cells around central vein, and there were also spotty necrosis and inflammatory cell infiltration in some parts of the sample; for intervention group, its fatty degeneration of hepatic cells was eased on the seventh day, and there was no necrosis and eased inflammatory cell infiltration; for model group, there were still focal necrosis and increased inflammatory cell infiltration on the fourteenth day; on the fourteenth day of intervention group, there were occasional spotty necrosis, apparently less inflammatory cell infiltration comparing to the fourteenth day of the model group.3.Results of Immunohistochemical Stains(1) NF-kB is positive mainly in hepatic cells around central vein, percentage of positive expression (P<0.01) of the model group increased sharply comparing to the control group on the seventh and fourteenth day; percentage of positive expression (seventh day P<0.05, fourteenth day P<0.01) of intervention group lowered remarkably comparing to the model groups; percentage of positive expression of the model group was much higher (P<0.05) in the 14th day than that of the 7th day.(2) TNF-αis positive mainly in hepatic cells around central vein, percentage of positive expression (P<0.01) of the model group increased sharply comparing to the control group on the seventh and fourteenth day; percentage of positive expression (P <0.05) of intervention group lowered remarkably comparing to the model groups; percentage of positive expression of the model group was much higher (seventh day P <0.01, fourteenth day P<0.05) in the 14th day than that of the 7th day. (3) TNF-αand NF-kB expression in hepatic tissues show positive correlation (r=0.573, P<0.05).4.Comparison on NF-kB and TNF-αLevel of Rats Serum:(1) Comparing the control group to the model group and the model group to the inter- vention group on the seventh and fourteenth day of experiment, their serum NF-kB (P<0.01) and TNF-a (P<0.01) level varied obviously. Serum NF-kB and TNF-a level (P<0.01) of the model group was much higher on the fourteenth day comparing to that of the seventh day.(2) Serum NF-kB and TNF-a level of the model group shows positive correlation (r=0.874, P<0.01) on the seventh and fourteenth day.Conclusion:1.PDTC is capable of preventing NF-kB activation in acute alcoholic liver injure in rats;2.There are positive correlations between TNF-a and NF-kB in their expression in liver tissue and content in blood serum of acute alcoholic liver injure in rats;3.NF-kB plays a role in acute alcoholic liver injure in rats by activating TNF-α.