BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its me...BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its mechanisms of expanding inflammatory responses in ALF are unclear.AIM To investigate the role and mechanisms of GSDMD-mediated hepatocyte pyroptosis through in vitro and in vivo experiments.METHODS The expression of pyroptosis pathway-associated proteins in liver tissues from ALF patients and a hepatocyte injury model was examined by Western blot.GSDMD short hairpin RNA(shRNA)was used to investigate the effects of downregulation of GSDMD on monocyte chemotactic protein 1(MCP1)and its receptor CC chemokine receptor-2(CCR2)in vitro.For in vivo experiments,we used GSDMD knockout mice to investigate the role and mechanism of GSDMD in a D-galactose/lipopolysaccharide(D-Galn/LPS)-induced ALF mouse model.RESULTS The levels of pyroptosis pathway-associated proteins in liver tissue from ALF patients and a hepatocyte injury model increased significantly.The level of GSDMD-N protein increased most obviously(P<0.001).In vitro,downregulation of GSDMD by shRNA decreased the cell inhibition rate and the levels of MCP1/CCR2 proteins(P<0.01).In vivo,GSDMD knockout dramatically eliminated inflammatory damage in the liver and improved the survival of DGaln/LPS-induced ALF mice(P<0.001).Unlike the mechanism of immune cell pyroptosis that involves releasing interleukin(IL)-1βand IL-18,GSDMDmediated hepatocyte pyroptosis recruited macrophages via MCP1/CCR2 to aggravate hepatocyte death.However,this pathological process was inhibited after knocking down GSDMD.CONCLUSION GSDMD-mediated hepatocyte pyroptosis plays an important role in the pathogenesis of ALF,recruiting macrophages to release inflammatory mediators by upregulating MCP1/CCR2 and leading to expansion of the inflammatory responses.GSDMD knockout can reduce hepatocyte death and inflammatory responses,thus alleviating ALF.展开更多
Objective:To investigate the regulatory mechanism in liver fibrosis progression by nuclear receptor of farnesoid X receptor(FXR)and the lipid droplet-associated protein of perilipin 5(PLIN5).Methods:FXR response eleme...Objective:To investigate the regulatory mechanism in liver fibrosis progression by nuclear receptor of farnesoid X receptor(FXR)and the lipid droplet-associated protein of perilipin 5(PLIN5).Methods:FXR response element(FXRE)upstream of PLIN5 gene was found by bioinformatics,and confirmed by a dual luciferase reporter gene system;a hepatic fibrosis model based on human hepatic stellate cell LX-2 was established by induction of transforming growth factor-β1(TGF-β1);mRNA and protein levels ofα-smooth muscle actin(α-SMA)and collagen栺were measured by qPCR and Western blot after transient overexpression of FXR or PLIN5;Oil red O staining was used to study the formation of lipid droplets.Results:The promoter region of the PLIN5 gene contained a known reverse repeats-1(IR-1);the gene expression of PLIN5 in LX-2 cells was up-regulated after FXR activation(P<0.01);overexpression of PLIN5 promoted the formation of lipid droplets and significantly reduced the TGF-β1 induced fibrosis gene expression(P<0.05);FXR activation showed no effects on the inhibition of LX-2 cells activation.Conclusion:Overexpression of PLIN5 promotes the formation of lipid droplets and inhibits activation of LX-2 cells.FXR might bind to the FXRE site upstream of PLIN5 gene and regulate its gene expression.In summary,FXR may prevent liver fibrosis progression partially by regulating lipid droplet-associated protein of PLIN5.展开更多
Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary tangles.Although amyloid plaques are the primar...Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary tangles.Although amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease treatment.Metabolic abnormalities are commonly observed in patients with Alzheimer's disease.The liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's disease.Notably,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's disease.In this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol metabolism.Furthermore,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.展开更多
Non-alcoholic fatty liver disease(NAFLD)is the main cause of chronic liver disease worldwide.Bupleurum is widely used in the treatment of non-alcoholic fatty liver,and saikosaponin D(SSD)is one of the main active comp...Non-alcoholic fatty liver disease(NAFLD)is the main cause of chronic liver disease worldwide.Bupleurum is widely used in the treatment of non-alcoholic fatty liver,and saikosaponin D(SSD)is one of the main active components of Bupleurum.The purpose of this study was to investigate the efficacy of SSD in the treatment of NAFLD and to explore the mechanism of SSD in the improvement of NAFLD based on“gut-liver axis”.Our results showed that SSD dose-dependently alleviated high fat diet-induced weight gain in mice,improved insulin sensitivity,and also reduced liver lipid accumulation and injury-related biomarkers aspartate aminotransferase(AST)and alanine aminotransferase(ALT).Further exploration found that SSD inhibited the mRNA expression levels of farnesoid X receptor(Fxr),small heterodimer partner(Shp),recombinant fibroblast growth factor 15(Fgf15)and apical sodium dependent bile acid transporter(Asbt)in the intestine,suggesting that SSD improved liver lipid metabolism by inhibiting intestinal FXR signaling.SSD can significantly reduce the gut microbiota associated with bile salt hydrolase(BSH)expression,such as Clostridium.Decreased BSH expression reduced the ratio of unconjugated to conjugated bile acids,thereby inhibiting the intestinal FXR.These data demonstrated that SSD ameliorated NAFLD potentially through the gut microbiota-bile acidintestinal FXR pathway and suggested that SSD is a promising therapeutic agent for the treatment of NAFLD.展开更多
Nogo-B受体(Nogo-B receptor,NgBR)参与脂肪肝和胰岛素敏感性的形成,但是并不清楚肝X受体(liver X receptor,LXR)激动剂是否能够调控NgBR的表达。文章使用人工合成的LXR激动剂(T0901317和GW3965)分析其对肝源细胞系中NgBR表达的影响,构...Nogo-B受体(Nogo-B receptor,NgBR)参与脂肪肝和胰岛素敏感性的形成,但是并不清楚肝X受体(liver X receptor,LXR)激动剂是否能够调控NgBR的表达。文章使用人工合成的LXR激动剂(T0901317和GW3965)分析其对肝源细胞系中NgBR表达的影响,构建正常或突变NgBR启动子,通过双荧光素酶报告基因系统检测LXR激动剂对启动子活性的影响;采用CRISPR-CAS9方法建立LXRα或LXRβ基因敲除的HepG2细胞系,通过Western Blot检测相关基因的表达变化;向ApoE-/-小鼠腹腔注射LXR激动剂T0901317,分析小鼠肝脏中NgBR的表达变化。结果发现,LXR激动剂能够通过激活LXR促进NgBR蛋白的表达,该诱导作用是以LXRE依赖的方式进行的,并且LXR的表达发挥着重要作用。在体内实验中,也证明了LXR激动剂T0901317上调NgBR蛋白表达。结果表明,NgBR是LXR的靶蛋白,LXR通过结合NgBR启动子LXRE序列促进其转录和翻译。展开更多
Nutrient metabolism is regulated by several factors.Social determinants of health with or without genetics are the primary regulator of metabolism,and an unhealthy lifestyle affects all modulators and mediators,leadin...Nutrient metabolism is regulated by several factors.Social determinants of health with or without genetics are the primary regulator of metabolism,and an unhealthy lifestyle affects all modulators and mediators,leading to the adaptation and finally to the exhaustion of cellular functions.Hepatic steatosis is defined by presence of fat in more than 5%of hepatocytes.In hepatocytes,fat is stored as triglycerides in lipid droplet.Hepatic steatosis results from a combination of multiple intracellular processes.In a healthy individual nutrient metabolism is regulated at several steps.It ranges from the selection of nutrients in a grocery store to the last step of consumption of ATP as an energy or as a building block of a cell as structural component.Several hormones,peptides,and genes have been described that participate in nutrient metabolism.Several enzymes participate in each nutrient metabolism as described above from ingestion to generation of ATP.As of now several publications have revealed very intricate regulation of nutrient metabolism,where most of the regulatory factors are tied to each other bidirectionally,making it difficult to comprehend chronological sequence of events.Insulin hormone is the primary regulator of all nutrients’metabolism both in prandial and fasting states.Insulin exerts its effects directly and indirectly on enzymes involved in the three main cellular function processes;metabolic,inflammation and repair,and cell growth and regeneration.Final regulators that control the enzymatic functions through stimulation or suppression of a cell are nuclear receptors in especially farnesoid X receptor and peroxisome proliferator-activated receptor/RXR ligands,adiponectin,leptin,and adiponutrin.Insulin hormone has direct effect on these final modulators.Whereas blood glucose level,serum lipids,incretin hormones,bile acids in conjunction with microbiota are intermediary modulators which are controlled by lifestyle.The purpose of this review is to overview the key players in the pathogenesis of metabolic dysfunction-associated steatotic liver disease(MASLD)that help us understand the disease natural course,risk stratification,role of lifestyle and pharmacotherapy in each individual patient with MASLD to achieve personalized care and target the practice of precision medicine.PubMed and Google Scholar databases were used to identify publication related to metabolism of carbohydrate and fat in states of health and disease states;MASLD,cardiovascular disease and cancer.More than 1000 publications including original research and review papers were reviewed.展开更多
目的·分析癌-睾丸抗原(cancer-testis antigen,CTA)家族成员SPANXB(sperm protein associated with the nucleus on the X chromosome B)在肝癌中的表达及其与肝癌患者预后之间的相关性,并探究SPANXB对肝癌细胞增殖的影响及其潜在...目的·分析癌-睾丸抗原(cancer-testis antigen,CTA)家族成员SPANXB(sperm protein associated with the nucleus on the X chromosome B)在肝癌中的表达及其与肝癌患者预后之间的相关性,并探究SPANXB对肝癌细胞增殖的影响及其潜在机制。方法·利用癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中的肝癌样本数据,分析SPANXB在肝癌组织中的表达及其与患者生存期的相关性。构建稳定敲低SPANXB与稳定过表达SPANXB的肝癌细胞系,利用活细胞成像实验、EdU细胞增殖实验和平板克隆形成实验评估SPANXB对肝癌细胞增殖的影响。通过RNA测序(RNA-sequence,RNA-seq)探究SPANXB调控肝癌细胞增殖的相关通路,并利用细胞周期实验验证SPANXB对肝癌细胞周期的影响。采用免疫沉淀-质谱联用技术(immunoprecipitation-mass spectrometry,IP-MS)探索与SPANXB相互作用的蛋白,并使用免疫共沉淀(co-immunoprecipitation,Co-IP)进行验证。结果·SPANXB mRNA在肝癌组织中的表达高于正常组织(P=0.003),且与肝癌患者的生存期呈负相关。稳定敲低SPANXB可降低肝癌细胞的增殖能力、克隆形成能力,而稳定过表达SPANXB则可促进这些过程。RNA-seq的结果显示,SPANXB的敲低可下调DNA复制与G1/S细胞周期转换相关通路,细胞周期实验的结果显示SPANXB的敲低可导致肝癌细胞周期发生改变。IP-MS和Co-IP结果显示,SPAXNB与有丝分裂停滞缺陷2样蛋白1(mitotic arrest deficient 2-like protein 1,MAD2L1)、WD重复域蛋白5(WD repeat domain 5,WDR5)等细胞周期相关蛋白存在相互作用。结论·SPANXB的高表达与肝癌的预后呈负相关,其可能通过与MAD2L1、WDR5相互作用调控细胞周期并增强肝癌细胞的增殖活性。展开更多
非酒精性脂肪性肝炎(Non-alcoholic steatohepatitis,NASH),又称代谢性脂肪性肝炎,是病理变化与酒精性肝炎相似但无过量饮酒史的临床综合征,好发于中年特别是超重肥胖个体。非酒精性脂肪性肝炎与肥胖、胰岛素抵抗、2型糖尿病、高脂血症...非酒精性脂肪性肝炎(Non-alcoholic steatohepatitis,NASH),又称代谢性脂肪性肝炎,是病理变化与酒精性肝炎相似但无过量饮酒史的临床综合征,好发于中年特别是超重肥胖个体。非酒精性脂肪性肝炎与肥胖、胰岛素抵抗、2型糖尿病、高脂血症等代谢紊乱关系密切,主要特征为肝细胞大泡性脂肪变伴肝细胞损伤和炎症,严重者可发展为肝硬化,但至今NASH尚无得到批准的治疗方案。在寻找有效的治疗方法时,解决代谢失调、炎症和抗纤维化的新策略不断涌现。法尼类X受体(Farnesoid X receptor,FXR)除了是胆汁酸代谢和肠肝循环的关键调节剂外,还参与调节代谢稳态,使其成为NASH中有吸引力的治疗靶点。本文综述了FXR激动剂对NASH治疗的研究进展。展开更多
Non-alcoholic fatty liver disease(NAFLD) is the hepatic manifestation of metabolic syndrome and is one of the most prevalent liver disorders worldwide. NAFLD can gradually progress to liver inflammation, fibrosis, cir...Non-alcoholic fatty liver disease(NAFLD) is the hepatic manifestation of metabolic syndrome and is one of the most prevalent liver disorders worldwide. NAFLD can gradually progress to liver inflammation, fibrosis, cirrhosis and even hepatocellular carcinoma. However, the pathogenesis of NAFLD is complex, and no efficient pharmaceutic treatments have yet been established for NAFLD. Accumulating data have shown that the farnesoid X receptor(FXR) plays important roles not only in bile acid metabolism, but also in lipid and carbohydrate homeostasis, inflammatory responses, among others. In this review, we aim to highlight the role of FXR in the pathogenesis and treatment of NAFLD.展开更多
The present study attempted to examine the effects of bile acid pool size on liver regeneration after hepatectomy.The rats were fed on 0.2% cholic acid(CA)or 2% cholestyramine for 7 days to induce a change in the bile...The present study attempted to examine the effects of bile acid pool size on liver regeneration after hepatectomy.The rats were fed on 0.2% cholic acid(CA)or 2% cholestyramine for 7 days to induce a change in the bile acid size,and then a partial hepatectomy(PH)was performed.Rats fed on the normal diet served as the controls.Measurements were made on the rate of liver regeneration,the labeling indices of PCNA,the plasma total bile acids(TBA),and the mRNA expression of cholesterol 7alpha-hydroxylase(CYP7A1),...展开更多
AIM To investigate the role of CXC chemokine receptor (CXCR)-7 and CXCL12 in lymph node and liver metastasis of gastric carcinoma. METHODS In 160 cases of gastric cancer, the expression of CXCR7 and CXCL12 in tumor an...AIM To investigate the role of CXC chemokine receptor (CXCR)-7 and CXCL12 in lymph node and liver metastasis of gastric carcinoma. METHODS In 160 cases of gastric cancer, the expression of CXCR7 and CXCL12 in tumor and matched tumoradjacent non-cancer tissues, in the lymph nodes around the stomach and in the liver was detected using immunohistochemistry to analyze the relationship between CXCR7/CXCL12 expression and clinicopathological features and to determine whether CXCR7 and CXCL12 constitute a biological axis to promote lymph node and liver metastasis of gastric cancer. Furthermore, the CXCR7 gene was silenced and overexpressed in human gastric cancer SGC-7901 cells, and cell proliferation, migration and invasiveness were measured by the MTT, wound healing and Transwell assays, respectively. RESULTS CXCR7 expression was up-regulated in gastric cancer tissues (P = 0.011). CXCR7/CXCL12 expression was significantly related to high tumor stage and lymph node (r = 0.338, P = 0.000) and liver metastasis (r = 0.629, P = 0.000). The expression of CXCL12 in lymph node and liver metastasis was higher than that in primary gastric cancer tissues (chi(2) = 6.669, P = 0.010; chi(2) = 25379, P = 0.000), and the expression of CXCL12 in lymph node and liver metastasis of gastric cancer was consistent with the positive expression of CXCR7 in primary gastric cancer (r = 0.338, P = 0.000; r = 0.629, P = 0.000). Overexpression of the CXCR7 gene promoted cell proliferation, migration and invasion. Silencing of the CXCR7 gene suppressed SGC-7901 cell proliferation, migration and invasion. Human gastric cancer cell lines expressed CXCR7 and showed vigorous proliferation and migratory responses to CXCL12. CONCLUSION The CXCR7/CXCL12 axis is involved in lymph node and liver metastasis of gastric cancer. CXCR7 is considered a potential therapeutic target for the treatment of gastric cancer.展开更多
AIM: To investigate the role of hepatic peroxisome proliferator-activated receptor-γ (PPAR-γ) in increased susceptibility to endotoxin-induced toxicity in rats with bile duct ligation during endotoxemia.METHODS: Mal...AIM: To investigate the role of hepatic peroxisome proliferator-activated receptor-γ (PPAR-γ) in increased susceptibility to endotoxin-induced toxicity in rats with bile duct ligation during endotoxemia.METHODS: Male Sprague-Dawley rats were subjected to bile duct ligation (BDL). Sham-operated animals served as controls. DNA binding were determined by polymerase chain reaction, Western blotting analysis,and electrophoretic mobility shift assay, respectively.BDL and sham-operated rats received a non-lethal dose of intraperitoneal lipopolysaccharide (LPS) injection (3 mg/kg, i.p.). Additionally, the potential beneficial effects of the PPAR-γ agonist rosiglitazone were determined in BDL and sham-operated rats treated with a non-lethal dose of LPS. Survival was assessed in BDL rats treated with a non-lethal dose of LPS and in sham-operatedrats treated at a lethal dose of LPS (6 mg/kg, i.p.).RESULTS: PPAR-γ activity in rats undergoing BDL wassignificantly lower than in the sham-controls. Hepatic PPAR-γ gene expression was downregulated at both them RNA and protein levels. In a parallel group, serumlevels of pro-inflammatory cytokines were nearly unde-tectable in the sham-operated rats. When challenged with a non-lethal dose of LPS (3 mg/kg), the BDL ratshad approximately a 2.4-fold increase in serum IL-6,a 2.7 fold increase in serum TNF-α, 2.2-fold increasein serum IL-1 and 4.2-fold increase in serum ALT. Thesurvival rate was significantly lower as compared with that in sham-operated group. Additionally, rosiglitazone significantly reduced the concentration of TNF-α, IL-1β, IL-6 and ALT in sham-operated rats, but not in BDL rats, in response to LPS (3 mg/kg). Also, the survival was improved by rosiglita zone in sham-operated rats challenged with a lethal dose of LPS, but not in BDL rats, even with a non-lethal dose of LPS (3 mg/kg).CONCLUSION: Obstructive jaundice downregulates hepatic PPAR-γ expression, which in turn may contributeto hypersensitivity towards endotoxin.展开更多
Acute liver failure (ALF) is a devastating clinical syndrome characterised by progressive encephalopathy, coagulopathy, and circulatory dysfunction, which commonly leads to multiorgan failure and death. Central to the...Acute liver failure (ALF) is a devastating clinical syndrome characterised by progressive encephalopathy, coagulopathy, and circulatory dysfunction, which commonly leads to multiorgan failure and death. Central to the pathogenesis of ALF is activation of the immune system with mobilisation of cellular effectors and massive production of cytokines. As key components of the innate immune system, monocytes and macrophages are postulated to play a central role in the initiation, progression and resolution of ALF. ALF in humans follows a rapidly progressive clinical course that poses inherent difficulties in delineating the role of these pivotal immune cells. Therefore, a number of experimental models have been used to study the pathogenesis of ALF. Here we consider the evidence from experimental and human studies of ALF on the role of monocytes and macrophages in acute hepatic injury and the ensuing extrahepatic manifestations, including functional monocyte deactivation and multiple organ failure.展开更多
BACKGROUND: Statins are suggested to preserve gallbladder function by suppressing pro-inflammatory cytokines and preventing cholesterol accumulation in gallbladder epithelial cells. They also affect cross-talk among t...BACKGROUND: Statins are suggested to preserve gallbladder function by suppressing pro-inflammatory cytokines and preventing cholesterol accumulation in gallbladder epithelial cells. They also affect cross-talk among the nuclear hormone receptors that regulate cholesterol-bile acid metabolism in the nuclei of hepatocytes. However, there is controversy over whether or how statins change the expression of peroxisome proliferator-activated receptor(PPAR)α, PPARγ, liver X receptor α(LXRα), farnesoid X receptor(FXR), ABCG5, ABCG8, and 7α-hydroxylase(CYP7A1) which are directly involved in the cholesterol saturation index in bile. METHODS: Human Hep3B cells were cultured on dishes. MTT assays were performed to determine the appropriate concentrations of reagents to be used. The protein expression of PPARα and PPARγ was measured by Western blotting analysis, and the mRNA expression of LXRα, FXR, ABCG5, ABCG8 and CYP7A1 was estimated by RT-PCR. RESULTS: In cultured Hep3B cells, pravastatin activated PPARα and PPARγ protein expression, induced stronger expression of PPARγ than that of PPARα, increased LXRα mRNA expression, activated ABCG5 and ABCG8 mRNA expression mediated by FXR as well as LXRα, enhanced FXR mRNA expression, and increased CYP7A1 mRNA expression mediated by the PPARγ and LXRα pathways, together or independently. CONCLUSION: Our data suggested that pravastatin prevents cholesterol gallstone diseases via the increase of FXR, LXRαand CYP7A1 in human hepatocytes.展开更多
基金Supported by the National Natural Science Foundation of China,No.81570543 and No.81560104
文摘BACKGROUND Massive hepatocyte death is the core event in acute liver failure(ALF).Gasdermin D(GSDMD)-mediated pyroptosis is a type of highly inflammatory cell death.However,the role of hepatocyte pyroptosis and its mechanisms of expanding inflammatory responses in ALF are unclear.AIM To investigate the role and mechanisms of GSDMD-mediated hepatocyte pyroptosis through in vitro and in vivo experiments.METHODS The expression of pyroptosis pathway-associated proteins in liver tissues from ALF patients and a hepatocyte injury model was examined by Western blot.GSDMD short hairpin RNA(shRNA)was used to investigate the effects of downregulation of GSDMD on monocyte chemotactic protein 1(MCP1)and its receptor CC chemokine receptor-2(CCR2)in vitro.For in vivo experiments,we used GSDMD knockout mice to investigate the role and mechanism of GSDMD in a D-galactose/lipopolysaccharide(D-Galn/LPS)-induced ALF mouse model.RESULTS The levels of pyroptosis pathway-associated proteins in liver tissue from ALF patients and a hepatocyte injury model increased significantly.The level of GSDMD-N protein increased most obviously(P<0.001).In vitro,downregulation of GSDMD by shRNA decreased the cell inhibition rate and the levels of MCP1/CCR2 proteins(P<0.01).In vivo,GSDMD knockout dramatically eliminated inflammatory damage in the liver and improved the survival of DGaln/LPS-induced ALF mice(P<0.001).Unlike the mechanism of immune cell pyroptosis that involves releasing interleukin(IL)-1βand IL-18,GSDMDmediated hepatocyte pyroptosis recruited macrophages via MCP1/CCR2 to aggravate hepatocyte death.However,this pathological process was inhibited after knocking down GSDMD.CONCLUSION GSDMD-mediated hepatocyte pyroptosis plays an important role in the pathogenesis of ALF,recruiting macrophages to release inflammatory mediators by upregulating MCP1/CCR2 and leading to expansion of the inflammatory responses.GSDMD knockout can reduce hepatocyte death and inflammatory responses,thus alleviating ALF.
基金National Natural Science Foundation of China(81973376)。
文摘Objective:To investigate the regulatory mechanism in liver fibrosis progression by nuclear receptor of farnesoid X receptor(FXR)and the lipid droplet-associated protein of perilipin 5(PLIN5).Methods:FXR response element(FXRE)upstream of PLIN5 gene was found by bioinformatics,and confirmed by a dual luciferase reporter gene system;a hepatic fibrosis model based on human hepatic stellate cell LX-2 was established by induction of transforming growth factor-β1(TGF-β1);mRNA and protein levels ofα-smooth muscle actin(α-SMA)and collagen栺were measured by qPCR and Western blot after transient overexpression of FXR or PLIN5;Oil red O staining was used to study the formation of lipid droplets.Results:The promoter region of the PLIN5 gene contained a known reverse repeats-1(IR-1);the gene expression of PLIN5 in LX-2 cells was up-regulated after FXR activation(P<0.01);overexpression of PLIN5 promoted the formation of lipid droplets and significantly reduced the TGF-β1 induced fibrosis gene expression(P<0.05);FXR activation showed no effects on the inhibition of LX-2 cells activation.Conclusion:Overexpression of PLIN5 promotes the formation of lipid droplets and inhibits activation of LX-2 cells.FXR might bind to the FXRE site upstream of PLIN5 gene and regulate its gene expression.In summary,FXR may prevent liver fibrosis progression partially by regulating lipid droplet-associated protein of PLIN5.
基金financially supported by the Science and Technology Innovation Program of Hunan Province,No.2022RC1220(to WP)China Postdoctoral Science Foundation,No.2022M711733(to ZZ)+2 种基金the National Natural Science Foundation of China,No.82160920(to ZZ)Hebei Postdoctoral Scientific Research Project,No.B2022003040(to ZZ)Hunan Flagship Department of Integrated Traditional Chinese and Western Medicine(to WP)。
文摘Alzheimer's disease,the primary cause of dementia,is characterized by neuropathologies,such as amyloid plaques,synaptic and neuronal degeneration,and neurofibrillary tangles.Although amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs,targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease treatment.Metabolic abnormalities are commonly observed in patients with Alzheimer's disease.The liver is the primary peripheral organ involved in amyloid-beta metabolism,playing a crucial role in the pathophysiology of Alzheimer's disease.Notably,impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's disease.In this review,we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol metabolism.Furthermore,we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.
基金supported by National Natural Science Foundation of China (82222071, 82273990, 82104253)the opening project of State Key Laboratory of Natural Medicines (SKLNMKF202208)
文摘Non-alcoholic fatty liver disease(NAFLD)is the main cause of chronic liver disease worldwide.Bupleurum is widely used in the treatment of non-alcoholic fatty liver,and saikosaponin D(SSD)is one of the main active components of Bupleurum.The purpose of this study was to investigate the efficacy of SSD in the treatment of NAFLD and to explore the mechanism of SSD in the improvement of NAFLD based on“gut-liver axis”.Our results showed that SSD dose-dependently alleviated high fat diet-induced weight gain in mice,improved insulin sensitivity,and also reduced liver lipid accumulation and injury-related biomarkers aspartate aminotransferase(AST)and alanine aminotransferase(ALT).Further exploration found that SSD inhibited the mRNA expression levels of farnesoid X receptor(Fxr),small heterodimer partner(Shp),recombinant fibroblast growth factor 15(Fgf15)and apical sodium dependent bile acid transporter(Asbt)in the intestine,suggesting that SSD improved liver lipid metabolism by inhibiting intestinal FXR signaling.SSD can significantly reduce the gut microbiota associated with bile salt hydrolase(BSH)expression,such as Clostridium.Decreased BSH expression reduced the ratio of unconjugated to conjugated bile acids,thereby inhibiting the intestinal FXR.These data demonstrated that SSD ameliorated NAFLD potentially through the gut microbiota-bile acidintestinal FXR pathway and suggested that SSD is a promising therapeutic agent for the treatment of NAFLD.
文摘Nogo-B受体(Nogo-B receptor,NgBR)参与脂肪肝和胰岛素敏感性的形成,但是并不清楚肝X受体(liver X receptor,LXR)激动剂是否能够调控NgBR的表达。文章使用人工合成的LXR激动剂(T0901317和GW3965)分析其对肝源细胞系中NgBR表达的影响,构建正常或突变NgBR启动子,通过双荧光素酶报告基因系统检测LXR激动剂对启动子活性的影响;采用CRISPR-CAS9方法建立LXRα或LXRβ基因敲除的HepG2细胞系,通过Western Blot检测相关基因的表达变化;向ApoE-/-小鼠腹腔注射LXR激动剂T0901317,分析小鼠肝脏中NgBR的表达变化。结果发现,LXR激动剂能够通过激活LXR促进NgBR蛋白的表达,该诱导作用是以LXRE依赖的方式进行的,并且LXR的表达发挥着重要作用。在体内实验中,也证明了LXR激动剂T0901317上调NgBR蛋白表达。结果表明,NgBR是LXR的靶蛋白,LXR通过结合NgBR启动子LXRE序列促进其转录和翻译。
文摘Nutrient metabolism is regulated by several factors.Social determinants of health with or without genetics are the primary regulator of metabolism,and an unhealthy lifestyle affects all modulators and mediators,leading to the adaptation and finally to the exhaustion of cellular functions.Hepatic steatosis is defined by presence of fat in more than 5%of hepatocytes.In hepatocytes,fat is stored as triglycerides in lipid droplet.Hepatic steatosis results from a combination of multiple intracellular processes.In a healthy individual nutrient metabolism is regulated at several steps.It ranges from the selection of nutrients in a grocery store to the last step of consumption of ATP as an energy or as a building block of a cell as structural component.Several hormones,peptides,and genes have been described that participate in nutrient metabolism.Several enzymes participate in each nutrient metabolism as described above from ingestion to generation of ATP.As of now several publications have revealed very intricate regulation of nutrient metabolism,where most of the regulatory factors are tied to each other bidirectionally,making it difficult to comprehend chronological sequence of events.Insulin hormone is the primary regulator of all nutrients’metabolism both in prandial and fasting states.Insulin exerts its effects directly and indirectly on enzymes involved in the three main cellular function processes;metabolic,inflammation and repair,and cell growth and regeneration.Final regulators that control the enzymatic functions through stimulation or suppression of a cell are nuclear receptors in especially farnesoid X receptor and peroxisome proliferator-activated receptor/RXR ligands,adiponectin,leptin,and adiponutrin.Insulin hormone has direct effect on these final modulators.Whereas blood glucose level,serum lipids,incretin hormones,bile acids in conjunction with microbiota are intermediary modulators which are controlled by lifestyle.The purpose of this review is to overview the key players in the pathogenesis of metabolic dysfunction-associated steatotic liver disease(MASLD)that help us understand the disease natural course,risk stratification,role of lifestyle and pharmacotherapy in each individual patient with MASLD to achieve personalized care and target the practice of precision medicine.PubMed and Google Scholar databases were used to identify publication related to metabolism of carbohydrate and fat in states of health and disease states;MASLD,cardiovascular disease and cancer.More than 1000 publications including original research and review papers were reviewed.
文摘目的·分析癌-睾丸抗原(cancer-testis antigen,CTA)家族成员SPANXB(sperm protein associated with the nucleus on the X chromosome B)在肝癌中的表达及其与肝癌患者预后之间的相关性,并探究SPANXB对肝癌细胞增殖的影响及其潜在机制。方法·利用癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据库中的肝癌样本数据,分析SPANXB在肝癌组织中的表达及其与患者生存期的相关性。构建稳定敲低SPANXB与稳定过表达SPANXB的肝癌细胞系,利用活细胞成像实验、EdU细胞增殖实验和平板克隆形成实验评估SPANXB对肝癌细胞增殖的影响。通过RNA测序(RNA-sequence,RNA-seq)探究SPANXB调控肝癌细胞增殖的相关通路,并利用细胞周期实验验证SPANXB对肝癌细胞周期的影响。采用免疫沉淀-质谱联用技术(immunoprecipitation-mass spectrometry,IP-MS)探索与SPANXB相互作用的蛋白,并使用免疫共沉淀(co-immunoprecipitation,Co-IP)进行验证。结果·SPANXB mRNA在肝癌组织中的表达高于正常组织(P=0.003),且与肝癌患者的生存期呈负相关。稳定敲低SPANXB可降低肝癌细胞的增殖能力、克隆形成能力,而稳定过表达SPANXB则可促进这些过程。RNA-seq的结果显示,SPANXB的敲低可下调DNA复制与G1/S细胞周期转换相关通路,细胞周期实验的结果显示SPANXB的敲低可导致肝癌细胞周期发生改变。IP-MS和Co-IP结果显示,SPAXNB与有丝分裂停滞缺陷2样蛋白1(mitotic arrest deficient 2-like protein 1,MAD2L1)、WD重复域蛋白5(WD repeat domain 5,WDR5)等细胞周期相关蛋白存在相互作用。结论·SPANXB的高表达与肝癌的预后呈负相关,其可能通过与MAD2L1、WDR5相互作用调控细胞周期并增强肝癌细胞的增殖活性。
文摘非酒精性脂肪性肝炎(Non-alcoholic steatohepatitis,NASH),又称代谢性脂肪性肝炎,是病理变化与酒精性肝炎相似但无过量饮酒史的临床综合征,好发于中年特别是超重肥胖个体。非酒精性脂肪性肝炎与肥胖、胰岛素抵抗、2型糖尿病、高脂血症等代谢紊乱关系密切,主要特征为肝细胞大泡性脂肪变伴肝细胞损伤和炎症,严重者可发展为肝硬化,但至今NASH尚无得到批准的治疗方案。在寻找有效的治疗方法时,解决代谢失调、炎症和抗纤维化的新策略不断涌现。法尼类X受体(Farnesoid X receptor,FXR)除了是胆汁酸代谢和肠肝循环的关键调节剂外,还参与调节代谢稳态,使其成为NASH中有吸引力的治疗靶点。本文综述了FXR激动剂对NASH治疗的研究进展。
基金Supported by National Nature Science Foundation of China,No.81273727 and No.81302927Innovation Program of Shanghai Municipal Education Commission,No.14YZ054
文摘Non-alcoholic fatty liver disease(NAFLD) is the hepatic manifestation of metabolic syndrome and is one of the most prevalent liver disorders worldwide. NAFLD can gradually progress to liver inflammation, fibrosis, cirrhosis and even hepatocellular carcinoma. However, the pathogenesis of NAFLD is complex, and no efficient pharmaceutic treatments have yet been established for NAFLD. Accumulating data have shown that the farnesoid X receptor(FXR) plays important roles not only in bile acid metabolism, but also in lipid and carbohydrate homeostasis, inflammatory responses, among others. In this review, we aim to highlight the role of FXR in the pathogenesis and treatment of NAFLD.
文摘The present study attempted to examine the effects of bile acid pool size on liver regeneration after hepatectomy.The rats were fed on 0.2% cholic acid(CA)or 2% cholestyramine for 7 days to induce a change in the bile acid size,and then a partial hepatectomy(PH)was performed.Rats fed on the normal diet served as the controls.Measurements were made on the rate of liver regeneration,the labeling indices of PCNA,the plasma total bile acids(TBA),and the mRNA expression of cholesterol 7alpha-hydroxylase(CYP7A1),...
基金Supported by the Tianjin Binhai New Area Health Industry Medical and Health Science Project,No.2011BHKY021Tianjin Binhai New Area Science and Technology Development Strategy Research Project,No.2012DK15W007Tianjin Binhai New Area Port Area Social Development Science and Technology Project,No.20120211
文摘AIM To investigate the role of CXC chemokine receptor (CXCR)-7 and CXCL12 in lymph node and liver metastasis of gastric carcinoma. METHODS In 160 cases of gastric cancer, the expression of CXCR7 and CXCL12 in tumor and matched tumoradjacent non-cancer tissues, in the lymph nodes around the stomach and in the liver was detected using immunohistochemistry to analyze the relationship between CXCR7/CXCL12 expression and clinicopathological features and to determine whether CXCR7 and CXCL12 constitute a biological axis to promote lymph node and liver metastasis of gastric cancer. Furthermore, the CXCR7 gene was silenced and overexpressed in human gastric cancer SGC-7901 cells, and cell proliferation, migration and invasiveness were measured by the MTT, wound healing and Transwell assays, respectively. RESULTS CXCR7 expression was up-regulated in gastric cancer tissues (P = 0.011). CXCR7/CXCL12 expression was significantly related to high tumor stage and lymph node (r = 0.338, P = 0.000) and liver metastasis (r = 0.629, P = 0.000). The expression of CXCL12 in lymph node and liver metastasis was higher than that in primary gastric cancer tissues (chi(2) = 6.669, P = 0.010; chi(2) = 25379, P = 0.000), and the expression of CXCL12 in lymph node and liver metastasis of gastric cancer was consistent with the positive expression of CXCR7 in primary gastric cancer (r = 0.338, P = 0.000; r = 0.629, P = 0.000). Overexpression of the CXCR7 gene promoted cell proliferation, migration and invasion. Silencing of the CXCR7 gene suppressed SGC-7901 cell proliferation, migration and invasion. Human gastric cancer cell lines expressed CXCR7 and showed vigorous proliferation and migratory responses to CXCL12. CONCLUSION The CXCR7/CXCL12 axis is involved in lymph node and liver metastasis of gastric cancer. CXCR7 is considered a potential therapeutic target for the treatment of gastric cancer.
基金Supported by China Postdoctoral Science Foundation, No.20080440626National Natural Science Foundation of China,No. 30700788 and No. 81001545Shanghai Leading Academic Discipline Project, No. S30203
文摘AIM: To investigate the role of hepatic peroxisome proliferator-activated receptor-γ (PPAR-γ) in increased susceptibility to endotoxin-induced toxicity in rats with bile duct ligation during endotoxemia.METHODS: Male Sprague-Dawley rats were subjected to bile duct ligation (BDL). Sham-operated animals served as controls. DNA binding were determined by polymerase chain reaction, Western blotting analysis,and electrophoretic mobility shift assay, respectively.BDL and sham-operated rats received a non-lethal dose of intraperitoneal lipopolysaccharide (LPS) injection (3 mg/kg, i.p.). Additionally, the potential beneficial effects of the PPAR-γ agonist rosiglitazone were determined in BDL and sham-operated rats treated with a non-lethal dose of LPS. Survival was assessed in BDL rats treated with a non-lethal dose of LPS and in sham-operatedrats treated at a lethal dose of LPS (6 mg/kg, i.p.).RESULTS: PPAR-γ activity in rats undergoing BDL wassignificantly lower than in the sham-controls. Hepatic PPAR-γ gene expression was downregulated at both them RNA and protein levels. In a parallel group, serumlevels of pro-inflammatory cytokines were nearly unde-tectable in the sham-operated rats. When challenged with a non-lethal dose of LPS (3 mg/kg), the BDL ratshad approximately a 2.4-fold increase in serum IL-6,a 2.7 fold increase in serum TNF-α, 2.2-fold increasein serum IL-1 and 4.2-fold increase in serum ALT. Thesurvival rate was significantly lower as compared with that in sham-operated group. Additionally, rosiglitazone significantly reduced the concentration of TNF-α, IL-1β, IL-6 and ALT in sham-operated rats, but not in BDL rats, in response to LPS (3 mg/kg). Also, the survival was improved by rosiglita zone in sham-operated rats challenged with a lethal dose of LPS, but not in BDL rats, even with a non-lethal dose of LPS (3 mg/kg).CONCLUSION: Obstructive jaundice downregulates hepatic PPAR-γ expression, which in turn may contributeto hypersensitivity towards endotoxin.
文摘Acute liver failure (ALF) is a devastating clinical syndrome characterised by progressive encephalopathy, coagulopathy, and circulatory dysfunction, which commonly leads to multiorgan failure and death. Central to the pathogenesis of ALF is activation of the immune system with mobilisation of cellular effectors and massive production of cytokines. As key components of the innate immune system, monocytes and macrophages are postulated to play a central role in the initiation, progression and resolution of ALF. ALF in humans follows a rapidly progressive clinical course that poses inherent difficulties in delineating the role of these pivotal immune cells. Therefore, a number of experimental models have been used to study the pathogenesis of ALF. Here we consider the evidence from experimental and human studies of ALF on the role of monocytes and macrophages in acute hepatic injury and the ensuing extrahepatic manifestations, including functional monocyte deactivation and multiple organ failure.
文摘BACKGROUND: Statins are suggested to preserve gallbladder function by suppressing pro-inflammatory cytokines and preventing cholesterol accumulation in gallbladder epithelial cells. They also affect cross-talk among the nuclear hormone receptors that regulate cholesterol-bile acid metabolism in the nuclei of hepatocytes. However, there is controversy over whether or how statins change the expression of peroxisome proliferator-activated receptor(PPAR)α, PPARγ, liver X receptor α(LXRα), farnesoid X receptor(FXR), ABCG5, ABCG8, and 7α-hydroxylase(CYP7A1) which are directly involved in the cholesterol saturation index in bile. METHODS: Human Hep3B cells were cultured on dishes. MTT assays were performed to determine the appropriate concentrations of reagents to be used. The protein expression of PPARα and PPARγ was measured by Western blotting analysis, and the mRNA expression of LXRα, FXR, ABCG5, ABCG8 and CYP7A1 was estimated by RT-PCR. RESULTS: In cultured Hep3B cells, pravastatin activated PPARα and PPARγ protein expression, induced stronger expression of PPARγ than that of PPARα, increased LXRα mRNA expression, activated ABCG5 and ABCG8 mRNA expression mediated by FXR as well as LXRα, enhanced FXR mRNA expression, and increased CYP7A1 mRNA expression mediated by the PPARγ and LXRα pathways, together or independently. CONCLUSION: Our data suggested that pravastatin prevents cholesterol gallstone diseases via the increase of FXR, LXRαand CYP7A1 in human hepatocytes.
