Hepatocyte growth factor promotes retinal pigment epithelium cell activity through MET/AKT signaling pathway

AIM:To explore the effects of hepatocyte growth factor(HGF)on retinal pigment epithelium(RPE)cell behaviors.METHODS:The human adult retinal pigment epithelial cell line-19(ARPE-19)were treated by HGF or mesenchymalepithelial transition factor(MET)inhibitor SU11274 in vitro.Cell viability was detected by a Cell Counting Kit-8 assay.Cell proliferation and motility was detected by a bromodeoxyuridine incorporation assay and a wound healing assay,respectively.The expression levels of MET,phosphorylated MET,protein kinase B(AKT),and phosphorylated AKT proteins were determined by Western blot assay.The MET and phosphorylated MET proteins were also determined by immunofluorescence assay.RESULTS:HGF increased ARPE-19 cells’viability,proliferation and migration,and induced an increase of phosphorylated MET and phosphorylated AKT proteins.SU11274 significantly reduced cell viability,proliferation,and migration and decreased the expression of MET and AKT proteins.SU11274 suppressed HGF-induced increase of viability,proliferation,and migration in ARPE-19 cells.Additionally,SU11274 also blocked HGF-induced phosphorylation of MET and AKT proteins.CONCLUSION:HGF enhances cellular viability,proliferation,and migration in RPE cells through the MET/AKT signaling pathway,whereas this enhancement is suppressed by the MET inhibitor SU11274.HGF-induced MET/AKT signaling might be a vital contributor of RPE cells survival.

Hepatocyte growth factor enhances the ability of dental pulp stem cells to ameliorate atherosclerosis in apolipoprotein E-knockout mice

BACKGROUND Atherosclerosis(AS),a chronic inflammatory disease of blood vessels,is a major contributor to cardiovascular disease.Dental pulp stem cells(DPSCs)are capable of exerting immunomodulatory and anti-inflammatory effects by secreting cytokines and exosomes and are widely used to treat autoimmune and inflam-mation-related diseases.Hepatocyte growth factor(HGF)is a pleiotropic cytokine that plays a key role in many inflammatory and autoimmune diseases.AIM To modify DPSCs with HGF(DPSC-HGF)and evaluate the therapeutic effect of DPSC-HGF on AS using an apolipoprotein E-knockout(ApoE-/-)mouse model and an in vitro cellular model.METHODS ApoE-/-mice were fed with a high-fat diet(HFD)for 12 wk and injected with DPSC-HGF or Ad-Null modified DPSCs(DPSC-Null)through tail vein at weeks 4,7,and 11,respectively,and the therapeutic efficacy and mechanisms were analyzed by histopathology,flow cytometry,lipid and glucose measurements,real-time reverse transcription polymerase chain reaction(RT-PCR),and enzyme-linked immunosorbent assay at the different time points of the experiment.An in vitro inflammatory cell model was established by using RAW264.7 cells and human aortic endothelial cells(HAOECs),and indirect co-cultured with supernatant of DPSC-Null(DPSC-Null-CM)or DPSC-HGF-CM,and the effect and mechanisms were analyzed by flow cytometry,RT-PCR and western blot.Nuclear factor-κB(NF-κB)activators and inhibitors were also used to validate the related signaling pathways.RESULTS DPSC-Null and DPSC-HGF treatments decreased the area of atherosclerotic plaques and reduced the expression of inflammatory factors,and the percentage of macrophages in the aorta,and DPSC-HGF treatment had more pronounced effects.DPSCs treatment had no effect on serum lipoprotein levels.The FACS results showed that DPSCs treatment reduced the percentages of monocytes,neutrophils,and M1 macrophages in the peripheral blood and spleen.DPSC-Null-CM and DPSC-HGF-CM reduced adhesion molecule expression in tumor necrosis factor-αstimulated HAOECs and regulated M1 polarization and inflammatory factor expression in lipopolysaccharide-induced RAW264.7 cells by inhibiting the NF-κB signaling pathway.CONCLUSION This study suggested that DPSC-HGF could more effectively ameliorate AS in ApoE-/-mice on a HFD,and could be of greater value in stem cell-based treatments for AS.

Dexamethasone potentiates the insulin-induced Srebp-1c expression in primary rat hepatocytes

The impacts of dexamethasone(Dex)and thyroid hormone T3 on the insulin-stimulated Srebp-1c expression were studied in primary rat hepatocytes. Primary hepatocytes from Sprague-Dawley rats were isolated, cultured and treated with insulin in the presence or absence of the indicated reagents over time. The mRNA levels of indicated genes were determined using real-time PCR. Insulin treatment induced the Srebp-1c expression and suppressed the Pck1 expression in a time-dependent manner. Dex treatment alone reduced the Srebp-1c expression, whereas potentiated the insulin-induced its expression, which reached to a level that was higher than the insulin alone group. On the other hand, insulin treatment completely suppressed the Dex-induced Pck1 expression in the same cells. T3 treatment did not affect the expressions of Srebp-1c and Pck1 alone or in the presence of absence of insulin or Dex. Interestingly, insulin treatment induced the Rxrg m RNA expression level in the absence or presence of T0901317, a specific agonist for the liver X receptor. Dex and insulin mutually affect each other's ability to regulate the expression levels of hepatic genes involved in glucose and fatty acid metabolism. Insulin induced Rxrg expression in primary hepatocytes, which may contribute to the induction of Srebp-1c expression in the same cells.

Cyclic feeding regime may delay aging in animals by enhancing the hepatocytes nuclei structure

Background:The liver is fundamental for keeping up the entire body’s homeostasis.The liver hepatocytes have been shown to undergo genomic instability with aging.The stability of the hepatocytes depends on its nuclear architecture.Calorie restriction has been shown to extend life-span favorably and this may be through the reorganization of the nuclear structure.Objective:To study the effect of cyclic feeding regime on the chromatin assembly anchored to the nuclear membrane scaffold of rat models hepatocytes nuclei.Method:Rats models underwent cyclic feeding regime,after which nuclei were isolated;then,we investigated the chromatin decondensation and nuclear membrane disintegration of the hepatocytes using fluorescence imaging methods.Results:In 60 seconds,protease decondensed the chromatin and disintegrated the nuclear membrane structure of controls.After the first fasting,the time increased to 145 seconds in 3-month-old rats.The first refeeding increased the time to 156 seconds with a further rise to 340 seconds following the second fasting,then dropped to 116 seconds by the second refeeding.20 months old rats showed 186 seconds increase in the time of chromatin decondensation and nuclear membrane disintegration after the first fasting,with a decrease to 140 seconds observed after first refeeding.The second fasting increased the time to 165 seconds,which then slightly decreased to 163 seconds after the second refeeding.Conclusion:These results show that intermittent fasting may have acted on chromatin histone interactions and the structural lamin networks of the nuclear membranes in bringing about nuclear stability,which is essential for normal cellular function.

Protective effects of polydatin against CCl_4-induced injury to primarily cultured rat hepatocytes

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Effects of Fuzhenghuayu decoction on collagen synthesis of cultured hepatic stellate cells,hepatocytes and fibroblasts in rats

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Assessing the anti-estrogenic activity of sodium pentachlorophenol in primary cultures of juvenile goldfish (Carassius auratus) hepatocytes using vitellogenin as a biomarker

Both pentachlorophenol and 2,3,7,8-tetrachlorodibenzo-p-dioxin （TCDD） had been studied widely because of their probable anti-estrogenic activity. Sodium pentachlorophenol （PCP-Na）, as a industrial product used in many fields, usually contains a trace of TCDD. The aim of this study was to assess the anti-estrogenic effect of PCP-Na in juvenile goldfish （Gurassius auratus） hepatocyte cultures using vitellogenin （VTG） as the biomarker. The ID50 of PCP-Na was investigated and then a series of concentrations （0.001 0.5 μg/ml） of PCP-Na were evaluated to estimate the anti-estrogenic activity. Results showed that PCP-Na was cytotoxic for hepatocytes even at very low concentration 〈1.21 μg/ml, and it could not induce VTG at any concentrations tested. Since it failed to stimulate VTG production, the possibility of its anti-estrogenic effect was tested, and a well-known anti-estrogenic compound-tamoxifen was used as positive control. PCP-Na caused a reduction in VTG synthesis in juvenile goldfish （Carassius auratus） hepatocytes at concentrations 〉0.1μg/ml when co-exposure with 1μg/ml 17β-estradiol （E2）, making its anti-estrogenic activity approximately as potent as tamoxifen. Our results indicate that PCP-Na can act as negative modulators of estrogenic function in juvenile goldfish （Carassius auratus） hepatocytes.

Reversible immortalization of human hepatocytes mediated by retroviral transfer and site-specific recombination

AIM: To establish a method for the reversible immortalization of human hepatocytes, which may offer a good and safe source of hepatocytes for practical applications.METHODS: We successfully isolated primary human hepatocytes from surgically resected liver tissue taken from a patient with liver hemangiomas. The freshly isolated cells were then immortalized with retroviral vector SSR#69 expressing simian virus 40 large T antigen(SV40T) and hygromycin-resistance genes flanked by paired loxP recombination targets.RESULTS: The freshly isolated hepatocytes with high viability(85%) were successfully immortalized using retroviral gene transfer of SV40 T. SV40 T in the immortalized cells was then excised by Cre/loxP site-specific recombination. This cell population exhibited the characteristics of differentiated hepatocytes.CONCLUSION: We successfully established reversibly immortalized human hepatocytes, which will provide an unlimited supply of cells for practical applications.

Primary porcine hepatocytes with portal vein serum cultured on microcarriers or in spheroidal aggregates

AIM To develop a culture mode providingdurable biomaterials with high yields andactivities used in bioartificial liver.METHODS Hepatocytes were isolated from awhole pig liver by Seglen’s method of orthotopicperfusion with collagenase.In culture onmicrocarriers,primary porcine hepatocyteswere inoculated at a concentration of 5×10~7/mLinto the static culture systems containing 2 g/LCytodex-3,then supplemented with 100 mL/Lfetal calf serum(FCS)or 100 mL/L porcineportal vein serum(PPVS)respectively.Inspheroidal aggregate culture hepatocytes wereinoculated into 100 mL siliconized flasks at aconcentration of 5.0×10~6/mL.RESULTS In culture on microcarriershepatocytes tended to aggregate on Cytodex-3obviously after being inoculated.Typical multi-cellular aggregated spheroids could be found inthe two systems 24 h-48 h after hepatocyteswere cultured.The morphological charact-eristics and synthetic functions were maintainedfor 5 wk in FCS culture system and 8 wk in PPVSculture system.In spheroidal aggregate cultureabout 80%-90% isolated hepatocytes becameaggregated spheroids 24h after cultured insuspension and mean diameter of the spheroidswas 100μm.The relationship among thehepatocytes resembled that in the liver in vivo.Synthetic functions of albumin and urea of the spheroids were twice those of hepatocytescultured on monolayers.CONCLUSION As high-yields and high-activitymodes of culture on microcarriers or inspheroidal aggregate culture with portal veinserum are promising to provide biomaterials forbioartificial liver(BAL)efficiently.

Human hepatocytes loaded in 3D bioprinting generate mini-liver

BACKGROUND: Because of an increasing discrepancy be-tween the number of potential liver graft recipients and the number of organs available, scientists are trying to create artiifcial liver to mimic normal liver function and therefore, to support the patient’s liver when in dysfunction. 3D printing technique meets this purpose. The present study was to test the feasibility of 3D hydrogel scaffolds for liver engineering. METHODS: We fabricated 3D hydrogel scaffolds with a bioprinter. The biocompatibility of 3D hydrogel scaffolds was tested. Sixty nude mice were randomly divided into four groups, with 15 mice in each group: control, hydrogel, hydro-gel with L02 (cell line HL-7702), and hydrogel with hepatocyte growth factor (HGF). Cells were cultured and deposited in scaffolds which were subsequently engrafted into livers after partial hepatectomy and radiation-induced liver damage (RILD). The engrafted tissues were examined after two weeks. The levels of alanine aminotransferase (ALT), aspartate amino-transferase (AST), albumin, total bilirubin, CYP1A2, CYP2C9, glutathione S-transferase (a-GST), and UDP-glucuronosyl transferase (UGT-2) were compared among the groups. He-matoxylin-eosin (HE) staining and immunohistochemistry of cKit and cytokeratin 18 (CK18) of engrafted tissues were evalu-ated. The survival time of the mice was also compared among the four groups. RESULTS: 3D hydrogel scaffolds did not impact the viability of cells. The levels of ALT, AST, albumin, total bilirubin, CY-P1A2, CYP2C9, a-GST and UGT-2 were signiifcantly improved in mice engrafted with 3D scaffold loaded with L02 compared with those in control and scaffold only (P<0.05). HE staining showed clear liver tissue and immunohistochemistry of cKit&nbsp;and CK18 were positive in the engrafted tissue. Mice treated with 3D scaffold+L02 cells had longer survival time compared with those in control and scaffold only (P<0.05). CONCLUSION: 3D scaffold has the potential of recreating liver tissue and partial liver functions and can be used in the reconstruction of liver tissues.

Prostaglandin E1 protects hepatocytes against endoplasmic reticulum stress-induced apoptosis via protein kinase A-dependent induction of glucose-regulated protein 78 expression

AIM To investigate the protective effect of prostaglandin E1(PGE1) against endoplasmic reticulum(ER) stressinduced hepatocyte apoptosis, and to explore its underlying mechanisms.METHODS Thapsigargin(TG) was used to induce ER stress in the human hepatic cell line L02 and hepatocarcinomaderived cell line Hep G2. To evaluate the effects of PGE1 on TG-induced apoptosis, PGE1 was used an hour prior to TG treatment. Activation of unfolded protein response signaling pathways were detected by western blotting and quantitative real-time RTPCR. Apoptotic index and cell viability of L02 cells and Hep G2 cells were determined with flow cytometry and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium] assay. RESULTS Pretreatment with 1 μmol/L PGE1 protected against TG-induced apoptosis in both L02 cells and Hep G2 cells. PGE1 enhanced the TG-induced expression of C/EBP homologous protein(CHOP), glucose-regulated protein(GRP) 78 and spliced X box-binding protein 1 at 6 h. However, it attenuated their expressions after 24 h. PGE1 alone induced protein and m RNA expressions of GRP78; PGE1 also induced protein expression of DNA damage-inducible gene 34 and inhibited the expressions of phospho-PKR-like ER kinase, phosphoeukaryotic initiation factor 2α and CHOP. Treatment with protein kinase A(PKA)-inhibitor H89 or KT5720 blocked PGE1-induced up-regulation of GRP78. Further, the cytoprotective effect of PGE1 on hepatocytes was not observed after blockade of GRP78 expression by H89 or small interfering RNA specifically targeted against human GRP78.CONCLUSION Our study demonstrates that PGE1 protects against ER stress-induced hepatocyte apoptosis via PKA pathwaydependent induction of GRP78 expression.

How hepatitis C virus invades hepatocytes: The mystery of viral entry

Hepatitis C virus(HCV)infection is a global health problem,with an estimated 170 million people being chronically infected.HCV cell entry is a complex multi-step process,involving several cellular factors that trigger virus uptake into the hepatocytes.The high-density lipoprotein receptor scavenger receptor class B type I,tetraspanin CD81,tight junction protein claudin-1,and occludin are the main receptors that mediate the initial step of HCV infection.In addition,the virus uses cell receptor tyrosine kinases as entry regulators,such as epidermal growth factor receptor and ephrin receptor A2.This review summarizes the current understanding about how cell surface molecules are involved in HCV attachment,internalization,and membrane fusion,and how host cell kinases regulate virus entry.The advances of the potential antiviral agents targeting this process are introduced.

Isolation and primary culture of rat hepatocytes

Objective: To find out an optimal condition for isola-tion and primary culture of hepatocytes.Method: Rat hepatocytes were isolated by a two-stepcollagenase perfusion, and cultured in hepatozyme-SFM. The reduction of MTT to formazan salt was ex-amined. Supernatant medium was collected for analy-sis of alanine aminotransferase（ALT） and ureagene-sis.Results: The two-step collagenase perfusion yielded39±12×10;cells/g liver tissue with a viability of88%±2%. Fine morphology and stable urea synthesisfor one week could be achieved when hepatocytes werecultured in Hepatozyme-SFM.Conclusion: High yield of hepatocytes can be isolatedwith two-step collagenese perfusion. Hepatozyme-SFM is suitable for sustained growth of hepatocytes.

Induction of Heme Oxygenase-1 in Human Hepatocytes to Protect Them From Ethanol-induced Cytotoxicity

Background/Aim We investigated the relationship between ethanol exposure and heme oxygenase (HO-1) in human hepatocytes in order to ascertain if induction of HO-1 can prevent ethanol induced cellular damage. Methods Dose-dependent (25-100 mmol/L) and time-dependent (0-24 h) ethanol exposure were used in the present study. HO-1 mRNA and protein expression were detected by PT-PCR and Western blot respectively. HO-1 activity was indicated by bilirubin and Fe2+ formation. Cytotoxicity was investigated by means of lactate dehydrogenate (LDH) and aspartate transaminase (AST) level in culture supernatants, as well as the intracellular formation of malondialdehyde (MDA), cellular glutathione (GSH) status and CYP 2E1 activity. Results We first demonstrated a dose-dependent response between ethanol exposure and HO-1 mRNA and protein expression in human hepatocytes. We further observed a time-dependent increase of HO-1 mRNA expression using 100 mmol/L ethanol starting 30 minutes after ethanol exposure, reaching its maximum between 3 h and 9 h. Being similar to what had been demonstrated with the mRNA level, increased protein expression started at 6 h after ethanol exposure, and kept continuous elevated over 18 h. In addition, we found that ethanol exposure to hepatocytes markedly increased HO-1 enzyme activity in a time-dependent manner measured as bilirubin and Fe2+ formation in human hepatocytes. Our results clearly showed that ethanol exposure caused a significant increase of LDH, AST, and MDA levels, while the antioxidant GSH was time-dependently reduced. Furthermore, we demonstrated that pre-administration of cobalt protoporphyrin (CoPP) induced HO-1 in human hepatocytes, and prevented an increase of MDA and a decrease of GSH. These effects could be partially reversed by zinc protoporphyrin (ZnPP), an antagonist of HO-1 induction. Conclusion HO-1 expression in cells or organs could lead to new strategies for better prevention and treatment of ethanol-induced oxidative damage in human liver.

Advances in cell sources of hepatocytes for bioartificial liver

BACKGROUND: Orthotopic liver transplantation (OLT) is the most effective therapy for liver failure. However, OLT is severely limited by the shortage of liver donors. Bioartificial liver (BAL) shows great potential as an alternative therapy for liver failure In recent years, progress has been made in BAL regarding genetically engineered cell lines, immortalized human hepatocytes, methods for preserving the phenotype of primary human hepatocytes, and other functional hepatocytes derived from stem cells. DATA SOURCES: A systematic search of PubMed and ISI Web of Science was performed to identify relevant studies in English language literature using the Key words such as liver failure bioartificial liver, hepatocyte, stem cells, differentiation, and immortalization. More than 200 articles related to the cell sources of hepatocyte in BAL were systematically reviewed. RESULTS: Methods for preserving the phenotype of primary human hepatocytes have been successfully developed. Many genetically engineered cell lines and immortalized human hepatocytes have also been established. Among these cell lines the incorporation of BAL with GS-HepG2 cells or alginate encapsulated HepG2 cells could prolong the survival time and improve pathophysiological parameters in an animal model of liver failure. The cBAL111 cells were evaluated using the AMC-BAL bioreactor, which could eliminate ammonia and lidocaine, and produce albumin. Importantly, BAL loading with HepLi-4 cells could significantly improve the blood biochemical parameters, and prolong the survival time in pigs with liver failure. Other functional hepatocytes differentiated from stem cells, such as human liver progenitor cells, have been successfully achieved. CONCLUSIONS: Aside from genetically modified liver cell lines and immortalized human hepatocytes, other functionalhepatocytes derived from stem cells show great potential as cell sources for BAL. BAL with safe and effective liver cells may be achieved for clinical liver failure in the near future.

miR-222 targets ACOX1, promotes triglyceride accumulation in hepatocytes

Background:Non-alcoholic fatty liver disease(NAFLD)is one of the most prevalent chronic liver diseases.However,the exact pathogenesis of NAFLD remains to be elucidated.Despite the association with tumors and cardiovascular diseases,the role of miR-222 in NAFLD remains unclear.The present study was to investigate the role of miR-222 in NAFLD.Methods:Wild-type C57BL/6 mice were fed a high-fat diet for 12 weeks to induce NAFLD.Normal human liver cell line(L02)was cultured with free fatty acid(FFA)-containing medium to stimulate cell steatosis.The mRNA levels of miR-222 and acyl Coenzyme A xidase 1(ACOX1)were detected by quantitative-PCR(Q-PCR).The prediction of ACOX1 as the target gene for miR-222 was conducted via TargetScan.The overexpression or inhibition of miR-222 was mediated by miR-222 mimics or antagomir,and intracellular triglyceride levels were measured using a triglyceride kit.Luciferase reporter assays verified ACOX1 as the target gene for miR-222.Results:miR-222 was significantly elevated in both the in vivo and in vitro NAFLD models.Overexpression of miR-222 significantly increased triglyceride content in the L02 cells,while inhibition of miR-222 expression restricted the accumulation of triglyceride.Overexpression of miR-222 significantly inhibited ACOX1 expression.Transient transfection assays verified that ACOX1 3-UTR luciferase reporter activity could be inhibited by miR-222 overexpression.Conclusions:The present study suggested that miR-222 promotes the accumulation of triglycerides by inhibiting ACOX1.

Senescent human hepatocytes express a unique secretory phenotype and promote macrophage migration

AIM:To develop a model of stress-induced senescence to study the hepatocyte senescence associated secretory phenotype(SASP).METHODS:Hydrogen peroxide treatment was used to induce senescence in the human Hep G2 hepatocyte cell line.Senescence was confirmed by cytochemical staining for a panel of markers including Ki67,p21,heterochromatin protein 1β,and senescence-associated-β-galactosidase activity.Senescent hepatocytes were characterised by gene expression arrays and quantitative polymerase chain reaction(q PCR),and conditioned media was used in proteomic analyses,a human chemokine protein array,and cell migration assays to characterise the composition and function of the hepatocyte SASP.RESULTS:Senescent hepatocytes induced classical markers of senescence(p21,heterochromatin protein1β,and senescence-associated-β-galactosidase activity);and downregulated the proliferation marker,Ki67.Hepatocyte senescence induced a 4.6-fold increase in total secreted protein(P=0.06)without major alterations in the protein profile.Senescence-induced genes were identified by microarray(Benjamini Hochbergcorrected P<0.05);and,consistent with the increase in secreted protein,gene ontology analysis revealed a significant enrichment of secreted proteins among inducible genes.The hepatocyte SASP included characteristic factors such as interleukin(IL)-8 and IL-6,as well as novel components such as SAA4,IL-32and Fibrinogen,which were validated by q PCR and/or chemokine protein array.Senescent hepatocyteconditioned medium elicited migration of inflammatory(granulocyte-macrophage colony stimulating factor,GM-CSF-derived),but not non-inflammatory(CSF-1-derived)human macrophages(P=0.022),which could contribute to a pro-inflammatory microenvironment in vivo,or facilitate the clearance of senescent cells.CONCLUSION:Our novel model of hepatocyte senescence provides insights into mechanisms by which senescent hepatocytes may promote chronic liver disease pathogenesis.

Lipopolysaccharide decreasing albumin expression in rat hepatocytes

The relations of the severity of hypoalbu-minemia to morbidity and mortality of patients with critical illness illustrate the need for better understanding of molecular mechanism of hypoalbuminemia. This study was undertaken to investigate the response of albumin synthesis to lipopolysaccharide(LPS)in rat hepatocytes in vitro in early acute phase of sepsis. METHODS:Hepatocytes were cultured at an initial cell density of 1.5×106 cells/well in 3 ml culture medium. There were two groups of samples which received either normal saline or 1 μg/L LPS randomly. Albumin mRNA in hepatocytes was assessed by reverse transcription-poly-merase chain reaction(RT-PCR) and albumin level in the supernatant was measured by ELISA at 0,2,8,12,24 hours after exposure. Meanwhile, the albumin precursor was evaluated at the same time points by flow cytometry. RESULTS:The quantitative changes of mRNA, albumin precursor and its protein were analogous. All of them tended to decline at 12 hours post-treatment and did not decrease significantly until 24 hours after LPS exposure. Meanwhile, albumin mRNA decreased about 30% and the levels of albumin precursor and albumin reduced approximately 50%. CONCLUSIONS: LPS can inhibit albumin synthesis in rat hepatocytes by prevention of albumin transcription. Moreover, the response of hepatic albumin synthesis to LPS changes with the stage of sepsis process. The results show that albumin metabolism in sepsis is a complicated process and further studies are required to understand the molecular mechanism of LPS-induced hypoalbuminemia in sepsis.