BACKGROUND:At present, liver transplantation is the best method to treat end-stage liver disease. UW solution is recognized as the best liver preservation solution, but it is expensive. Moreover, the extracel ular fluid of high K+condition is inconsistent with human physiology. Because transient hyperkalemia of UW solution often causes cardiac arrest, research and development of the new liver preservation solution already brook no delay. OBJECTIVE:To study the protective effect of self-designed KYL solution on ischemia reperfusion injury in macaque donor liver. METHODS:A total of eight recipient macaques and eight donor macaques were selected in this study. Each group contained KYL solution group (n=4) and UW solution group (n=4). Donor liver was perfused and cryopreserved for 4 hours and subjected to al ogenic orthotopic liver transplantation. At 30 minutes and 6 hours after transplantation, bile production was recorded. Blood was obtained and used to detect concentrations of aspartate aminotransferase, alanine aminotransferase, nitric oxide, endothelin-1 and tumor necrosis factor-α. Liver tissue was col ected and detected under the light microscope. RESULTS AND CONCLUSION:Bile secretion was found in both groups. Bile secretion production increased as time went on (P<0.05). At 30 minutes and 6 hours after donor liver reperfusion, serum aspartate aminotransferase and alanine aminotransferase concentrations were lower in the KYL solution group than in the UW solution group (P<0.05). No significant difference was found in levels of serum nitric oxide, endothelin 1 and tumor necrosis factor alpha between the two groups (P>0.05). Under light microscope, morphological observation of liver tissue revealed that cel ular edema was evident in the UW solution group than in the KYL solution group. Results suggest that the effect of KYL solution on preventing ischemia/reperfusion injury was identical to the UW solution, and partial effect was better than UW solution.

BACKGROUND:At present, liver transplantation is the only way to cure end-stage liver disease, but the complications after transplantation is stil an important factor of affecting the long-term survival of patients who received orthotopic liver transplantation, therefore it is necessary to establish a stable animal transplantation model. OBJECTIVE:To establish rat models of orthotopic liver transplantation. METHODS:After inhalation anesthesia with ether, 204 SD rats were perfused with 2-4℃ Ringer’s solution through the abdominal aorta. In order to reduce warm ischemia of the liver, the liver was not turned over before perfusion. The suprahepatic inferior vena cava was cut off along the phrenic ring after perfusion. No further trimming was needed when dressing, so as not to damage the vena cava. The donor liver was removed and preserved in 4℃Ringer’s liquid. The receptor liver was cut off and alogeneic orthotopic liver transplantation was performed using modified two-cuff method. After transplantation, rats could automaticaly turn over and drink water. Surviving more than 3 days is regarded as a successful transplantation. RESULTS AND CONCLUSION:102 liver transplantations were performed in 204 rats, with 86 rats surviving more than 3 days. The success rate of transplantation was 84%. The results demonstrate that rat models of orthotropic liver transplantation can be constructed successfuly through improving techniques.

BACKGROUND:Acelular dermal matrix is a cel-free natural tissue scaffold similar to human soft tissue, which is easy to shape and has non-toxic side effects. It has been used to repair the urethra and ureter. OBJECTIVE:To investigate the effect of acelular dermal matrix on the repair of bile duct injury. METHODS:Thirty Diannan miniature pigs were randomly divided into three groups: in blank group, the bile duct was resected folowed by end to end anastomosis; in experimental group, bile duct defect model was made folowed by repair with acelular dermal matrix; in control group, bile duct defect model was made folowed by repair with expanded polytetrafluoroethylene. At 6 and 24 weeks after repair, bile duct patches and surrounding tissues were taken for immunohistochemical observation and RT-PCR detection. RESULTS AND CONCLUSION: Compared with the control and blank group, the expression of cytokeratin was higher, but the expression of transforming growth factor β1 was lower in the experimental group. Within 24 weeks after repair, the total mRNA level of transforming growth factor β1 was lower in the experimental group than the other two groups (P < 0.05), but the total mRNA levels of insulin-like growth factor 2 and vascular endothelial growth factor were higher in the experimental group (P < 0.05). These findings indicate that the acelular dermal matrix for repair of bile duct injury can promote angiogenesis and bile duct epithelial regeneration, but not increase the formation of scars.

OBJECTIVETo investigate whether RNA interference (RNAi) of LXRα gene in donor rats with fatty liver improves liver graft function after transplantation.

METHODSFifty donor SD rats were fed a high-fat diet and 56% alcohol to induce macrovesicular steatosis exceeding 60% in the liver. The donor rats were injected via the portal veins with 7 × 10⁷ TU LXRα-RNAi-LV mixture (n=25) or negative control-LV (NC-LV) vector (n=25) 72 h before orthotopic liver transplantation. At 2, 24, and 72 h after the transplantation, the recipient rats were sacrificed to examine liver transaminases, liver graft histology, immunostaining (TUNEL), and protein and mRNA levels of LXRα.

RESULTSLentivirus-LXRα RNAi inhibited LXRα gene expression at both the mRNA and protein levels in the liver graft and reduced the expressions of SREBP-1c and CD36 as compared with the controls, resulting also in reduced fatty acid accumulation in the hepatocytes. The recipient rats receiving RNAi-treated grafts showed more obvious reduction in serum ALT, AST, IL-1β and TNF-α levels, and exhibited milder hepatic pathologies than the control rats after the transplantation. TUNEL assay demonstrated a significant reduction in cell apoptosis in LXRα-RNAi-LV-treated liver grafts, and the rats receiving treated liver grafts had a prolonged mean overall survival time.

CONCLUSIONLXRα-RNAi-LV treatment of the donor rats with fatty liver can significantly down-regulate LXRα gene expression in the liver graft and improve the graft function and recipient rat survival after liver transplantation.

Animals ; Fatty Liver ; genetics ; surgery ; Gene Expression Regulation ; Hepatocytes ; cytology ; Lentivirus ; Liver ; physiology ; Liver Transplantation ; Liver X Receptors ; Orphan Nuclear Receptors ; genetics ; RNA Interference ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the optimal approach of lentiviral vector transfection for effective delivery of exogenous gene into the liver.

METHODSThe lentiviral vector was delivered via the ileocolic vein of the ileocecus (portal vein group) or via the caudal vein of SD rats. The effect gene transfection into the liver was assessed by observing the expression of green fluorescence protein expression carried by the lentiviral vector, silencing of LXRα mRNA expression mediated by RNA interference, and liver transaminase changes. The efficiency and safety of the two approaches of transfection were evaluated.

RESULTSAll the rats receiving lentiviral transfection survived. In the portal vein group, abundant green fluorescence was detected in the liver at 96 h following the transfection and lasted till 14 days, whereas only weak fluorescence was observed in the caudal vein group. The results of RT-PCR demonstrated a significant higher rate of LXRα knock-down in portal vein group than in caudal vein group (0.135∓0.002 vs 0.713∓0.036, P<0.05). No significant difference in ALT levels found between the two groups.

CONCLUSIONSInfusion via the potal vein is effective for gene transfection into the liver, and puncture from the ileocolic vein of ileocecus can guarantee the survival of rats and improve the transfection efficiency without causing liver injury.

Animals ; Gene Expression ; Genetic Vectors ; Lentivirus ; genetics ; Liver ; metabolism ; Male ; RNA Interference ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley ; Transfection

Autophagy is a highly conserved cellular self-regulatory mechanism， which primarily occurs in the lysosomes or vacuoles of mammalian and yeast cells and plays a critical role in maintaining cellular homeostasis and metabolic balance. When cells encounter stress conditions like nutrient deprivation， physical or chemical stimuli， infections， and oxidative stress， or when damaged or aging organelles accumulate in the cytoplasm， the autophagic process is activated. This process degrades and recycles damaged proteins and organelles， removes potentially harmful substances， in which the degradation products are used for energy supply and macromolecule resynthesis， thereby help maintain the cellular homeostasis. Autophagy activators are compounds or drugs that can promote the cellular self-clearance process （such as mTOR inhibitors， AMPK activators， SIRT1 activators， lysosome enhancers， etc.）. They enhance autophagy activity by acting on autophagy-related signaling pathways or proteins， thereby regulating cellular and metabolic processes， and consequently exerting an impact on the organism. With the deepening of research， more and more small molecule compounds with autophagic activity have been discovered. As autophagy activators， these small molecule compounds have shown great application potential in the treatment of malignant tumors， nervous system diseases， metabolic diseases， etc. Some related drugs have even entered the clinical trial stage and achieved good efficacy. This article discusses the mechanisms of various types of autophagy activators and their potential applications in diseases， aiming to provide a reference for the further development and application of autophagy activators in diseases.

Objective To investigate the optimal approach of lentiviral vector transfection for effective delivery of exogenous gene into the liver. Methods The lentiviral vector was delivered via the ileocolic vein of the ileocecus (portal vein group) or via the caudal vein of SD rats. The effect gene transfection into the liver was assessed by observing the expression of green fluorescence protein expression carried by the lentiviral vector, silencing of LXRα mRNA expression mediated by RNA interference, and liver transaminase changes. The efficiency and safety of the two approaches of transfection were evaluated. Results All the rats receiving lentiviral transfection survived. In the portal vein group, abundant green fluorescence was detected in the liver at 96 h following the trasnfection and lasted till 14 days, whereas only weak fluorescence was observed in the caudal vein group. The results of RT-PCR demonstrated a significant higher rate of LXRαknock-down in portal vein group than in caudal vein group (0.135 ± 0.002 vs 0.713 ± 0.036, P<0.05). No significant difference in ALT levels found between the two groups. Conclusion Infusion via the potal vein is effective for gene transfection into the liver, and puncture from the ileocolic vein of ileocecus can guarantee the survival of rats and improve the transfection efficiency without causing liver injury.

Objective To investigate whether RNA interference (RNAi) of LXRα gene in donor rats with fatty liver improves liver graft function after transplantation. Methods Fifty donor SD rats were fed a high-fat diet and 56% alcohol to induce macrovesicular steatosis exceeding 60% in the liver. The donor rats were injected via the portal veins with 7 × 107 TU LXRα-RNAi-LV mixture (n=25) or negative control-LV (NC-LV) vector (n=25) 72 h before orthotopic liver transplantation. At 2, 24, and 72 h after the transplantation, the recipient rats were sacrificed to examine liver transaminases, liver graft histology, immunostaining (TUNEL), and protein and mRNA levels of LXRα. Results Lentivirus-LXRα RNAi inhibited LXRα gene expression at both the mRNA and protein levels in the liver graft and reduced the expressions of SREBP-1c and CD36 as compared with the controls, resulting also in reduced fatty acid accumulation in the hepatocytes. The recipient rats receiving RNAi-treated grafts showed more obvious reduction in serum ALT, AST, IL-1βand TNF-αlevels, and exhibited milder hepatic pathologies than the control rats after the transplantation. TUNEL assay demonstrated a significant reduction in cell apoptosis in LXRα-RNAi-LV-treated liver grafts, and the rats receiving treated liver grafts had a prolonged mean overall survival time. Conclusion LXRα-RNAi-LV treatment of the donor rats with fatty liver can significantly down-regulate LXRαgene expression in the liver graft and improve the graft function and recipient rat survival after liver transplantation.

Background/Aims: Liver cirrhosis involves chronic inflammation and progressive fibrosis.Among various immune cells, CD8+ T cells are considered a major contributor to hepatic inflammation and fibrosis. However, the exact molecular pathways governing CD8+ T-cell-mediated effects in cirrhosis remain unclear. Methods: This study analyzed transcriptomic and single-cell sequencing data to elucidate CD8+ T-cell heterogeneity and implications in cirrhosis. Results: Weighted gene co-expression analysis of bulk RNA-seq data revealed an association between cirrhosis severity and activated T-cell markers like HLA and chemokine genes. Furthermore, single-cell profiling uncovered eight CD8+ T-cell subtypes, notably, effector memory (Tem) and exhausted (Tex) T cells. Tex cells, defined by PDCD1, LAG3, and CXCL13 expression, were increased in cirrhosis, while Tem cells were decreased. Lineage tracing and differential analysis highlighted CXCL13+ Tex cells as a terminal, exhausted subtype of cells with roles in PD-1 signaling, glycolysis, and T-cell regulation. CXCL13+ Tex cells displayed T-cell exhaustion markers like PDCD1, HAVCR2, TIGIT, and TNFRSF9. Functional analysis implicated potential roles of these cells in immunosuppression. Finally, a CXCL13+ Tex-cell gene signature was found that correlated with cirrhosis severity and poorer prognosis of liver cancer. Conclusions In summary, this comprehensive study defines specialized CD8+ T-cell subpopulations in cirrhosis, with CXCL13+ Tex cells displaying an exhausted phenotype associated with immune dysregulation and advanced disease. Key genes and pathways regulating these cells present potential therapeutic targets.

Background/Aims: Liver cirrhosis involves chronic inflammation and progressive fibrosis.Among various immune cells, CD8+ T cells are considered a major contributor to hepatic inflammation and fibrosis. However, the exact molecular pathways governing CD8+ T-cell-mediated effects in cirrhosis remain unclear. Methods: This study analyzed transcriptomic and single-cell sequencing data to elucidate CD8+ T-cell heterogeneity and implications in cirrhosis. Results: Weighted gene co-expression analysis of bulk RNA-seq data revealed an association between cirrhosis severity and activated T-cell markers like HLA and chemokine genes. Furthermore, single-cell profiling uncovered eight CD8+ T-cell subtypes, notably, effector memory (Tem) and exhausted (Tex) T cells. Tex cells, defined by PDCD1, LAG3, and CXCL13 expression, were increased in cirrhosis, while Tem cells were decreased. Lineage tracing and differential analysis highlighted CXCL13+ Tex cells as a terminal, exhausted subtype of cells with roles in PD-1 signaling, glycolysis, and T-cell regulation. CXCL13+ Tex cells displayed T-cell exhaustion markers like PDCD1, HAVCR2, TIGIT, and TNFRSF9. Functional analysis implicated potential roles of these cells in immunosuppression. Finally, a CXCL13+ Tex-cell gene signature was found that correlated with cirrhosis severity and poorer prognosis of liver cancer. Conclusions In summary, this comprehensive study defines specialized CD8+ T-cell subpopulations in cirrhosis, with CXCL13+ Tex cells displaying an exhausted phenotype associated with immune dysregulation and advanced disease. Key genes and pathways regulating these cells present potential therapeutic targets.