Study on the intervention time windows of cell apoptosis in acute liver injury in mice

Objective To study the proliferation and apoptosis of related proteins in pathological liver tissues of alcohol-induced mice,and establish a model and time-evolution rule of liver cell apoptosis,which can be used to guide the clinical treatment of acute alcoholic liver injury.Methods A total of 30 male KM mice were fed in a clean grade animal room at the Capital Medical University and then randomly (random number) separated into two groups.The 10 mice in the normal group were fed without ethanol,while the other 20 mice in the experimental group were given a one-time grant of 50％ ethanol (12 mL/kg) by gavage.The mice in the experimental group were killed at two time points,6 h for 10 mice and 12 h for the other 10,after the intragastric administration.Hematoxylin and eosin (HE) staining was used to observe the morphological changes of liver in mice.The concentrations of T-ERK,p-ERK,PKC,p-PKC and caspase-3 were determined by the Western-blot method.The data were analyzed by Analysis of variance (ANOVA) method using statistical software SPSS 11.5 and criterion P ＜ 0.05 is chosen to determine differences that are statistically significant.Results By observing the behavioral changes and morphological indexes of mice,we confirmed the success of the model for acute alcoholic liver injury.During the process of re-building the model,no mice died.The mice in the experimental group appeared in drunken states,such as sleepiness and slowness of movement.Compared to the normal group,the experimental subgroup at the 6 h point showed no difference statistical significant; while the experimental subgroup at the 12 h point showed obvious histological changes in tissues,including the disorder of hepatic lobule structure and fatty vacuolization of hepatocytes.At the same time,in the experimental subgroup at the 12 h point,both P-ERK and P-PKC significantly decreased [(2.41 ±0.38),(0.97 ±0.25),F=4.82,P＜0.05; (0.16 ±0.00),(0.08 ± 0.01),F =29.63,P ＜ 0.05],but caspase-3 significantly increased [(0.30 ± 0.02),(0.11 ± 0.01),F =34.38,P ＜ 0.05].Conclusions In mice after intragastric administration of large doses of alcohol,the hepatic cell apoptosis appeared mainly after 6 h but before 12 h,therefore 6 ～ 12 h might be the time window to inhibit the cell apoptosis of mice' s acute liver injury from alcohol induction. Key words: Mice;  Acute alcoholic liver injury;  Apoptosis;  Proliferation;  T-ERK;  P-ERK;  PKC;  P-PKC ;  caspase-3