Expression of intrahepatic chemokine CXCL13 in a mouse model of primary biliary cholangitis / 医学研究生学报

Objective The expression of chemokine C-X-C motif ligand 13 (CXCL13) within liver in primary biliary cholangitis (PBC) patients is significantly increased, but its origin and mechanism is not clear yet.The study aimed to investigate the expression of CXCL13 in the liver of mice through establishing a mouse model of PBC.Methods C57BL/6 mice were randomly divided into experiment group (n=20) control group(n=10).The mice in the experimental group were intraperitoneally injected with polyriboinosinic polyribocytidylic acid (Poly I:C) while the mice in control group were injected with PBS of the same volume.The level of serum AMA was quantified by ELISA and intrahepatic inflammatory cells were assessed by HE staining.Kupffer cells, liver sinusoidal endothelial cells, and infiltrating lymphocytes in the liver of mice were collected by in situ perfusion enzyme digestion and magnetic bead separation methods.The transcriptional level of intrahepatic CXCL13 in liver tissues and cell subpopulations were detected by qPCR.Results The serum AMA titers of the mice in experiment group increased gradually with the prolonging of modeling time and the positive rates at the 4th, 8th, and 12th week after the first injection of Poly I:C were 5.9%, 52.9% and 76.5% respectively.While the serum AMA titers of the mice in control group were at a lower level through the modeling process, with only 2 mice presenting a little higher level above positive cutoff value at the 12th week.The results of HE staining in liver tissues of both groups showed that there were a great amount of intensely infiltrating inflammatory cells in the mice of experimental group while no inflammatory cell infiltration were found in the mice of control group.The separation purity of Kupffer cells and liver sinusoidal endothelial cells in the mice of experiment group tested by flow cytometry were 76%-80%, 68%-72% respectively.Compared with the CXCL13 mRNA level in Kupffer cells [2.34(0.22-8.64)], the expression levels in liver sinusoidal endothelial cells and infiltrating lymphocytes declined[0.27(0.03-1.64), 0.05(0-0.22), P<0.05].Conclusion The chemokine CXCL13 is predominantly produced by Kupffer cells in the liver of PBC mice established by Poly I:C injection.

Establishment of a diet-induced obesity model in zebrafish larvae / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a diet-induced obesity model in zebrafish larvae.</p><p><b>METHODS</b>At 7 days post-fertilization (dpf), 200 zebrafish larvae with normal development were randomly allocated to two groups with the feeding quantity of 30 mg per day (normal feeding group) or 180 mg per day (overfed group) for 20 days. The weight, length, BMI, triglyceride (TG) and total cholesterol (TCH) of each group were measured. Whole-mount Oil Red O staining, frozen Oil Red O staining and hematoxylin-eosin (HE) staining were used to estimate the rate of hepatic steatosis and liver histology of the zebrafish. The dynamic change of hepatic lipid droplets and distribution of adipose tissue were observed with Nile Red staining in overfed zebrafish in vivo.</p><p><b>RESULTS</b>The weight, length, BMI and TG of overfed zebrafish were significantly increased compared with those in normal feeding group. Whole-mount Oil Red O staining showed that the percent of hepatic steatosis in overfed group (89.4%) was markedly higher than that in normal feeding group (20.7%). Macrovesicular steatosis was observed in the liver of the overfed larvae. Nile Red staining visualized hepatic lipid droplets and the distribution of larval adipose tissue, which increased with feeding time in the overfed zebrafish. Starving larvae showed depletion of fat and hepatic lipid, and adipose tissue was induced after refeeding.</p><p><b>CONCLUSIONS</b>We successfully established an diet-induced obesity model in zebrafish larva, in which Nile Red staining allows in vivo observation of the adipocytes and hepatic lipid droplets.</p>

Establishment of a hepatic fibrosis model induced by diethylnitrosamine in zebrafish / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a zebrafish model of liver fibrosis via diethylnitrosamine (DEN)-induced liver injury.</p><p><b>METHODS</b>A total of 120 wild-type 3-month-old zebrafish were randomly divided into DEN-treated group and control group. The survival rate and behavioral changes of each group were observed. After treatment with DEN for 2, 4, and 6 weeks, liver index was measured, and liver fibrosis was evaluated with HE staining, Gomori staining and Sirius red staining.</p><p><b>RESULTS</b>No obvious behavioral change was observed in DEN-treated group during the experiment. Compared with that in control group, the liver index of zebrafish in DEN-treated group showed no significantly changes at the time points of observation. Proliferation of reticulate fibers was found in 30% of zebrafish treated with DEN for 4 weeks, and the rate increased to 80% at 6 weeks when reticulate fibers and collagen fibers actively proliferated to result in fiber collapse and formation of fibrotic nodules.</p><p><b>CONCLUSION</b>A stable zebrafish liver fibrosis model was successfully established by inducing liver damage to facilitate studies of the pathogenesis of liver fibrosis and screening therapeutic drugs.</p>

Effect of alpha-lipoic acid on cardiomyocyte apoptosis following renal ischemia-reperfusion injury in rats / 中华麻醉学杂志

ObjectiveTo evaluate the effect of alpha-lipoic acid (ALA) on cardiomyocyte apoptosis following renal ischemia-reperfusion injury(RIRI) in rats.MethodsThirty-six male SD rats weighing 250-280 g were randomly divided into 3 groups ( n =12 each): group sham operation (group S) ; group I/R and group I/R + ALA ( group L).The model of RIRI was produced by occlusion of renal artery and vein for 45 min followed by 24 h reperfusion,in group S the renal pedicles were exposed but not occluded.In group L ALA infusion (30 mg/kg) was given via tail vein at 20 mln before ischemia and at 20 min before reperfusion,while in group I/R the equal volume of solution (35％ polyethylene glycol + 60％ physiological saline + 5％ ethanol) was infused instead of ALA.The animals were saerificed at the end of 24 h of reperfusion,blood samples were taken for detecting concentrations of serum creatinine (Cr) and malondialdehyde (MDA).Then the hearts were immediately removed for determination of SOD activity,MDA content,cardiomyocyte apoptosis (flow cytometry) and Bcl-2/Bax ratio (immunohistology).ResultsSerum Cr concentration,serum and myocardium MDA levels and cardiomyocyte apoptosis were significantly increased after RIRI in groups I/R and L as compared with group S ( P ＜ 0.05).ALA treatment significantly decreased serum Cr concentration,serum and myocardium MDA levels,cardiomyocyte apoptosis and increased SOD activity and Bcl-2/Bax ratio ( P ＜ 0.05).ConclusionALA can attenuate myocardium injury by inhibiting cardiomyocyte apoptosis following RIRI in rats.