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Shizhu J Xiangwei M Xun S Mingzi H Bingrong L Dexia K Xinghong W Fenghua P 《The Turkish journal of gastroenterology》2012,23(4):344-352
Background/aims: Stem cell transplantation has theoretical potential for the treatment of certain liver diseases. However, the use of bone marrow mononuclear cells as a therapy for liver disease has received little attention. The present study was to examine whether bone marrow mononuclear cells might be useful in the management of acute liver failure in an animal model. Materials and Methots: Bone marrow mononuclear cells were harvested from BALB/c mice and then labeled with the fluorescent dye PKH26. The labeled cells were subsequently infused into the tail veins of mice in which hepatic injury had been induced by CCl4 toxicity. After transplantation, the labeled cells in the liver were studied by fluorescent microscopy, and the levels of proliferating cell nuclear antigen and albumin were quantified in bone marrow mononuclear cell-treated and untreated groups. Serum aminotransferase activity was also monitored at various time points post-liver injury. Results: Transplanted bone marrow mononuclear cells labeled with PKH26 were found to populate the damaged liver around the portal and centrolobular regions, and they appeared to differentiate into albumin-producing hepatocyte-like cells. Animals that received bone marrow mononuclear cells also showed a trend toward improved liver enzymes as well enhanced survival rates, relative to controls. Conclusions: These findings suggest that systemically delivered bone marrow mononuclear cells may relocate to and be retained by the injured liver; transplantation of bone marrow mononuclear cells showed an overall beneficial effect in a murine model of acute liver failure. 相似文献
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Zhituo Li Ming Lu Jiangtao Chu Xin Qiao Xianzhi Meng Bei Sun Weihui Zhang Dongbo Xue 《Pancreatology》2012,12(3):248-256
BackgroundBile acids are the initiating factors of biliary acute pancreatitis. Bile acids can induce the activation of intracellular zymogen, thus leading injury in pancreatic acinar cells. Pathological zymogen activation in pancreatic acinar cells is a common feature of all types of acute pancreatitis. The proteins expressed in pancreatic acinar cells during the activation of zymogen may determine the severity of acute pancreatitis. The present study aims to determine the differentially expressed proteins in taurolithocholic acid 3-sulfate-stimulated pancreatic acinar cells as an in vitro model for acute pancreatitis.MethodsRat pancreatic acinar AR42J cells were treated with taurolithocholic acid 3-sulfate for 20 min. Laser confocal scanning microscopy and flow cytometry were used to detect activated trypsinogen in pancreatic acinar AR42J cells. After the determination of trypsinogen activation, proteome analysis was performed to identify the proteins differentially expressed in taurolithocholic acid 3-sulfate-treated cells and non-treated cells.ResultsAfter treatment with taurolithocholic acid 3-sulfate for 20 min, the activation of trypsinogen in AR42J cells was concurrent with changes in the protein expression profile. Thirty-nine differentially expressed proteins were detected; among these, 23 proteins were up-regulated and 16 proteins were down-regulated. KEGG analysis indicated that these proteins are involved in cellular metabolic pathways, cellular defensive mechanisms, intracellular calcium regulation and cytoskeletal changes.ConclusionThe expression of proteins in the pancreatic acinar cell changes at the early stage of biliary acute pancreatitis. These differentially expressed proteins will provide valuable information to understand the pathophysiologic mechanism biliary acute pancreatitis and may be useful for prognostic indices of acute pancreatitis. 相似文献
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Xiaofen Jin Juanjuan Zhang Qiuzi Yi Feilong Meng Jialing Yu Yanchun Ji Jun Q. Mo Yi Tong Pingping Jiang Min-Xin Guan 《Investigative ophthalmology & visual science》2021,62(7)
PurposeTo investigate the mechanism underlying the synergic interaction between Leber''s hereditary optic neuropathy (LHON)-associated ND1 and mitochondrial tyrosyl-tRNA synthetase (YARS2) mutations.MethodsMolecular dynamics simulation and differential scanning fluorimetry were used to evaluate the structure and stability of proteins. The impact of ND1 3635G>A and YARS2 p.G191V mutations on the oxidative phosphorylation machinery was evaluated using blue native gel electrophoresis and enzymatic activities assays. Assessment of reactive oxygen species (ROS) production in cell lines was performed by flow cytometry with MitoSOX Red reagent. Analysis of effect of mutations on autophagy was undertaken via flow cytometry for autophagic flux.ResultsMembers of one Chinese family bearing both the YARS2 p.191Gly>Val and m.3635G>A mutations exhibited much higher penetrance of optic neuropathy than those pedigrees carrying only the m.3635G>A mutation. The m.3635G>A (p.Ser110Asn) mutation altered the ND1 structure and function, whereas the p.191Gly>Val mutation affected the stability of YARS2. Lymphoblastoid cell lines harboring both m.3635G>A and p.191Gly>Val mutations revealed more reductions in the levels of mitochondrion-encoding ND1 and CO2 than cells bearing only the m.3635G>A mutation. Strikingly, both m.3635G>A and p.191Gly>Val mutations exhibited decreases in the nucleus-encoding subunits of complex I and IV. These deficiencies manifested greater defects in the stability and activities of complex I and complex IV and overproduction of ROS and promoted greater autophagy in cell lines harboring both m.3635G>A and p.191Gly>Val mutations compared with cells bearing only the m.3635G>A mutation.ConclusionsOur findings provide new insights into the pathophysiology of LHON arising from the synergy between ND1 3635G>A mutation and mitochondrial YARS2 mutations. 相似文献