Dihydromyricetin alleviates carbon tetrachloride-induced acute liver injury via JNK-dependent mechanism in mice

AIM: To assess the effects of dihydromyricetin(DHM) as a hepatoprotective candidate in reducing hepatic injury and accelerating hepatocyte proliferation after carbon tetrachloride(CCl4) treatment.METHODS: C57 BL/6 mice were used in this study. Mice were orally administered with DHM(150 mg/kg) for 4 d after CCl4 treatment. Serum and liver tissue samples were collected on days 1, 2, 3, 5 and 7 after CCl4 treatment. The anti-inflammatory effect of DHM was assessed directly by hepatic histology detection and indirectly by serum levels of aspartate aminotransferase(AST), alanine aminotransferase(ALT), albumin, and superoxide dismutase(SOD). Inflammatory cytokines, such as interleukin(IL)-1β, IL-6 and tumor necrosis factor-α(TNF-α), were detected using ELISA kits. Proliferating cell nuclear antigen(PCNA) staining was used to evaluate the role of DHM in promoting hepatocyte proliferation. Hepatocyte apoptosis wasmeasured by TUNEL assay.Furthermore,apoptosis proteins Caspases-3,6,8,and 9 were detected by Western blot.SP600125 were used to confirm whether DHM regulated liver regeneration through JNK/TNF-αpathways.RESULTS:DHM showed a strong anti-inflammatory effect on CCl4-induced liver injury in mice.DHM could significantly decrease serum ALT,AST,IL-1β,IL-6 and TNF-αand increase serum albumin,SOD and liver SOD compared to the control group after CCl4 treatment(P0.05).PCNA results indicated that DHM could significantly increase the number of PCNA positive cells compared to the control(348.9±56.0 vs 107.1±31.4,P0.01).TUNEL assay showed that DHM dramatically reduced the number of apoptotic cells after CCl4 treatment compared to the control(365.4±99.4 vs 90.5±13.8,P0.01).Caspase activity detection showed that DHM could reduce the activities of Caspases-8,3,6 and 9 compared to the control(P0.05).The results of Western blot showed that DHM increased the expression of JNK and decreased TNF-αexpression.However,DHM could not affect TNF-αexpression after SP600125 treatment.Furthermore,DHM could significantly improve the survival rate of acute liver failure(ALF)mice(73.3%vs 20.0%,P0.0001),and SP600125 could inhibit the effect of DHM.CONCLUSION:These findings demonstrate that DHM alleviates CCl4-induced liver injury,suggesting that DHM is a promising candidate for reversing liver injury and ALF.     

Hepatoprotective effects of baicalein against CCl4-induced acute liver injury in mice

AIM: To investigate the hepatoprotective effect of baicalein against carbon tetrachloride (CCl₄)-induced liver damage in mice.METHODS: Mice were orally administered with baicalein after CCl₄ injection, and therapeutic baicalein was given twice a day for 4 d. The anti-inflammation effects of baicalein were assessed directly by hepatic histology and serum alanine aminotranferease and aspartate aminotransferase measurement. Proliferating cell nuclear antigen was used to evaluate the effect of baicalein in promoting hepatocyte proliferation. Serum interleukin (IL)-6, IL-1β and tumor necrosis factor-α (TNF-α) levels were measured by enzyme-linked immunosorbent assay and liver IL-6, TNF-α, transforming growth factor-α (TGF-α), hepatocyte growth factor (HGF) and epidermal growth factor (EGF) genes expression were determined by quantitative real-time polymerase chain reaction.RESULTS: CCl₄-induced acute liver failure model offers a survival benefit in baicalein-treated mice. The data indicated that the mRNA levels of IL-6 and TNF-α significantly increased within 12 h after CCl₄ treatment in baicalein administration groups, but at 24, 48 and 72 h, the expression of IL-6 and TNF-α was kept at lower levels compared with the control. The expression of TGF-α, HGF and EGF was enhanced dramatically in baicalein administration group at 12, 24, 48 and 72 h. Furthermore, we found that baicalein significantly elevated the serum level of TNF-α and IL-6 at the early phase, which indicated that baicalein could facilitate the initiating events in liver regeneration.CONCLUSION: Baicalein may be a therapeutic candidate for acute liver injury. Baicalein accelerates liver regeneration by regulating TNF-α and IL-6 mediated pathways.     

I_κB kinase-beta inhibitor attenuates hepatic fibrosis in mice

AIM: To investigate the anti-fibrosis effect of IκB kinase-beta inhibitor (IKK2 inhibitor IMD0354) in liver fibrosis. METHODS: Twenty male C57BL6 mice were divided into four groups. Five high-fat fed mice were injected with lipopolysaccharide (LPS, 10 mg/kg) intraperitoneally and five high-fat fed mice were without LPS injection to build models of liver injury, and the intervention group (five mice) was injected intraperitoneally with IKK2 inhibitor (IMD 30 mg/kg for 14 d), while the remaining five mice rec...     

Hepatoprotective effect of Cichorium intybus L.,a traditional Uighur medicine,against carbon tetrachloride-induced hepatic fibrosis in rats

AIM:To investigate the hepatoprotective effect of a Cichorium intybus L.extract(CIE)on CCl4-induced hepatic fibrosis in rats.METHODS:Seventy-two male Wistar albino rats were randomly divided into six groups of twelve rats each.The normal control group was allowed free access to food and water.Liver injury was performed in the remaining five groups with an i.p.injection of a 1.0mL/kg CCl4 and olive oil(2:3 v/v)mixture,twice weekly for 8 weeks.All rats,with the exception of the injury model group,were intragastrically(i.g.,)administered quantum satis(q.s.)dosages[CIE group:6,18,and 54 mg/kg,respectively;Fu Fang Bie Jia Ruan Gan Pian(FFBJRGP)group:780 mg/kg].The oral administration of different drugs was performed on the day before CCl4 administration and subsequently once per day for8 wk.The serum levels of aspartate aminotransferase(AST),alanine aminotransferase(ALT),hexadecenoic acid(HA),laminin(LN),hydroxyproline(Hyp),and glutathione(GSH),malondialdehyde(MDA)and superoxide dismutase(SOD)in the rat livers were measured.Histopathological changes in the liver were assessed for each group using HE staining and a Masson Trichrome examination.The expression of transforming growth factor-β1(TGF-β1)andα-smooth muscle actin(α-SMA)was examined by immunohistochemical analysis.RESULTS:CIE at oral doses of 6,18,and 54 g/kg per day showed a significant hepatoprotective effect,especially at a dose of 54 g/kg per day.CIE doses reduced the levels of AST(149.04±34.44,P<0.01),ALT(100.72±27.19,P<0.01),HA(548.50±65.09,P<0.01),LN(28.69±3.32,P<0.01)and Hyp(263.33±75.82,P<0.01).With regards to hepatoprotective activity,the CIE dose of 54 g/kg per day produced the largest significant effect by increasing GSH(3.11±0.81),SOD(269.98±33.77,P<0.01)and reducing MDA(2.76±0.51,P<0.01)levels in the liver.The expressions of TGF-β1 andα-SMA were measured by immunohistology and found to be significantly reduced by CIE in a dose-dependent manner.     

Titanium dioxide induced inflammation in the small intestine

AIM: To investigate the effects of titanium dioxide (TiO₂) nanoparticles (NPTiO₂) and microparticles (MPTiO₂) on the inflammatory response in the small intestine of mice.METHODS: Bl 57/6 male mice received distilled water suspensions containing TiO₂ (100 mg/kg body weight) as NPTiO₂ (66 nm), or MPTiO₂ (260 nm) by gavage for 10 d, once a day; the control group received only distilled water. At the end of the treatment the duodenum, jejunum and ileum were extracted for assessment of cytokines, inflammatory cells and titanium content. The cytokines interleukin (IL)-1b, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13, IL-17, IL-23, tumor necrosis factor-α (TNF-α), intracellular interferon-γ (IFN-γ) and transforming growth factor-β (TGF-β) were evaluated by enzyme-linked immunosorbent assay in segments of jejunum and ileum (mucosa and underlying muscular tissue). CD4⁺ and CD8⁺ T cells, natural killer cells, and dendritic cells were evaluated in duodenum, jejunum and ileum samples fixed in 10% formalin by immunohistochemistry. The titanium content was determined by inductively coupled plasma atomic emission spectrometry.RESULTS: We found increased levels of T CD4⁺ cells (cells/mm²) in duodenum: NP 1240 ± 139.4, MP 1070 ± 154.7 vs 458 ± 50.39 (P < 0.01); jejunum: NP 908.4 ± 130.3, MP 813.8 ± 103.8 vs 526.6 ± 61.43 (P < 0.05); and ileum: NP 818.60 ± 123.0, MP 640.1 ± 32.75 vs 466.9 ± 22.4 (P < 0.05). In comparison to the control group, the groups receiving TiO₂ showed a statistically significant increase in the levels of the inflammatory cytokines IL-12, IL-4, IL-23, TNF-α, IFN-γ and TGF-β. The cytokine production was more pronounced in the ileum (mean ± SE): IL-12: NP 33.98 ± 11.76, MP 74.11 ± 25.65 vs 19.06 ± 3.92 (P < 0.05); IL-4: NP 17.36 ± 9.96, MP 22.94 ± 7.47 vs 2.19 ± 0.65 (P < 0.05); IL-23: NP 157.20 ± 75.80, MP 134.50 ± 38.31 vs 22.34 ± 5.81 (P < 0.05); TNFα: NP 3.71 ± 1.33, MP 5.44 ± 1.67 vs 0.99 ± 019 (P < 0.05); IFNγ: NP 15.85 ± 9.99, MP 34.08 ± 11.44 vs 2.81 ± 0.69 (P < 0.05); and TGF-β: NP 780.70 ± 318.50, MP 1409.00 ± 502.20 vs 205.50 ± 63.93 (P < 0.05).CONCLUSION: Our findings indicate that TiO₂ particles induce a Th1-mediated inflammatory response in the small bowel in mice.     

Effects of urotensin-Ⅱ on cytokines in early acute liver failure in mice

AIM:To investigate urotensin-Ⅱ(UⅡ) and its effects on tumor necrosis factor(TNF)-α and interleukin(IL)-1β in early acute liver failure(ALF).METHODS:We investigated the time-dependent alteration in UⅡ levels and its effects on TNF-αand IL-1β in liver and blood in the early stage of lipopolysaccharide/D-galactosamine-induced ALF.RESULTS:After lipopolysaccharide/D-galactosamine challenge,UⅡ rose very rapidly and reached a maximal level 0.5 h,and the level remained significantly elevated after 2 h(P 0.05).Six hours after challenge,UⅡ began to degrade,but remained higher than at 0 h(P 0.05).Pretreatment with urantide,an inhibitor of the UⅡ receptor,suppressed the degree of UⅡ increase in liver and blood at 6 h after challenge(P 0.05 vs paired controls).In addition,liver and blood TNF-α increased from 1 to 6 h,and reached a peak at 1 and 2 h,respectively; however,IL-1β did not rise until 6 h after challenge.Urantide pretreatment inhibited the degree of TNF-α and IL-1β increase following downregulation of UⅡ post-challenge(all P 0.05).CONCLUSION:UⅡ plays a role in the pathogenesis and priming of ALF by triggering an inflammatory cascade and driving the early release of cytokines in mice.     

Mechanism of action of gypenosides on type 2 diabetes and non-alcoholic fatty liver disease in rats

AIM:To explore the mechanism of action of gypenosides(GPs)on type 2 diabetes mellitus and non-alcoholic fatty liver disease(T2DM-NAFLD)in rats.METHODS:Sixty rats were randomly divided into a healthy group,an untreated disease model group andGP-treatment groups.The study involved the evaluation of biochemical parameters,including serum aspartate transaminase(AST),alanine transferase(ALT),blood glucose(BG),triglycerides(TG)and total cholesterol(TC).Additionally,the protective effect of the treatments were confirmed histopathologically and the expression of TNF-αand NF-κB in the rat liver was analyzed using immunohistochemistry.The expression of proliferatoractivated receptor gamma(PPARγ)and cytochrome P450(CYP450)1A1 m RNA was determined by quantitative RTPCR.RESULTS:GP treatments at oral doses of 200,400,and800 mg/kg per day significantly decreased the levels of serum AST and ALT(P0.05,P0.01),especially at the dose of 800 mg/kg per day.To a similar extent,GP at800 mg/kg per day reduced the levels of BG(4.19±0.47,P0.01),TG(80.08±10.05,P0.01),TC(134.38±16.39,P0.01)and serum insulin(42.01±5.04,P0.01).The expression of TNF-αand NF-κB measured by immunohistochemistry was significantly reduced by GPs in a dose-dependent manner,and the expression of PPARγand CYP4501A1 m RNA,as measured using quantitative real-time PCR,were significantly down-regulated by GPs.Moreover,GPs decreased the infiltration of liver fats and reversed the histopathological changes in a dosedependent manner.CONCLUSION:This study suggests that GPs have a protective effect against T2DM-NAFLD by down-regulating the expression of TNF-αand NF-κB proteins,and PPARγand CYP4501A1 m RNAs.     

Ethyl pyruvate protects against experimental acute-on-chronic liver failure in rats

AIM:To investigate the protective effects of ethyl pyruvate(EP) on acute-on-chronic liver failure(ACLF) in rats.METHODS:An ACLF model was established in rats,and animals were randomly divided into normal,model and EP treatment groups.The rats in EP treatment group received EP(40 mg/kg) at 3 h,6 h,12 h and 24 h after induction of ACLF.Serum endotoxin,high mobility group box-1(HMGB1),alanine transaminase(ALT),tumor necrosis factor-(TNF-),interferon-(IFN-),interleukin(IL)-10 and IL-18 levels,changes of liver histology and HMGB1 expressions in liver tissues were detected at 48 h after induction of ACLF.The effects of EP on the survival of ACLF rats were also observed.RESULTS:Serum levels of endotoxin(0.394 ± 0.066 EU/mL vs 0.086 ± 0.017 EU/mL,P 0.001),HMGB1(35.42 ± 10.86 g/L vs 2.14 ± 0.27 g/L,P 0.001),ALT(8415.87 ± 3567.54 IU/L vs 38.64 ± 8.82 IU/L,P 0.001),TNF-(190.77 ± 12.34 ng/L vs 124.40 ± 4.12 ng/L,P 0.001),IFN-(715.38 ± 86.03 ng/L vs 398.66 ± 32.91 ng/L,P 0.001),IL-10(6.85 ± 0.64 ng/L vs 3.49 ± 0.24 ng/L,P 0.001) and IL-18(85.19 ± 3.49 ng/L vs 55.38 ± 1.25 ng/L,P 0.001) were significantly increased,and liver tissues presented severe pathological injury in the model group compared with the normal group.However,EP administration significantly improved hepatic histopathology and reduced the serum levels of endotoxin(0.155 ± 0.045 EU/mL vs 0.394 ± 0.066 EU/mL,P 0.001) and inflammatory cytokines(11.13 ± 2.58 g/L vs 35.42 ± 10.86 g/L for HMGB1,3512.86 ± 972.67 IU/L vs 8415.87 ± 3567.54 IU/L for ALT,128.55 ± 5.76 ng/L vs 190.77 ± 12.34 ng/L for TNF-,438.16 ± 38.10 ng/L vs 715.38 ± 86.03 ng/L for IFN-,3.55 ± 0.36 ng/L vs 6.85 ± 0.64 ng/L for IL-10,and 60.35 ± 1.63 ng/L vs 85.19 ± 3.49 ng/L for IL-18,respectively,P 0.001),and the levels of HMGB1 in liver tissues regardless of treatment time after induction of ACLF.EP treatment at the four time points prolonged the median survival time of ACLF rats(60 h) to 162 h,120 h,102 h and 78 h,respectively(2 = 41.17,P 0.0001).CONCLUSION:EP administration can protect against ACLF in rats,and is a potential and novel therapeutic agent for severe liver injury.     

Inhibition of sphingosine kinase 1 ameliorates acute liver failure by reducing high-mobility group box 1 cytoplasmic translocation in liver cells

AIM: To determine the therapeutic potential of sphingosine kinase 1(Sphk1) inhibition and its underlying mechanism in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced acute liver failure(ALF).METHODS: Balb/c mice were randomly assigned to different groups,with ALF induced by intraperitoneal injection of D-Ga IN(600 mg/kg) and LPS(10 μg/kg). The Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels at different time points within one week were determined using a multi-parametric analyzer. Serum high-mobility group box 1(HMGB1),tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6,IL-10,and sphingosine-1-phosphate were detected by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after acute liver injury induction were assessed by hematoxylin and eosin staining. HMGB1 expression in hepatocytes and cytoplasmic translocation were detected by immunohistochemistry. Expression of Sphk1 in liver tissue and peripheral blood mononuclear cells(PBMCs) was analyzed by Western blot.RESULTS: The expression of Sphk1 in liver tissue and PBMCs was upregulated in Gal N/LPS-induced ALF. Upregulated Sphk1 expression in liver tissue was mainly caused by Kupffer cells,the resident macrophages of the liver. The survival rates of mice in the N,Ndimethylsphingosine(DMS,a specific inhibitor of Sph K1) treatment group were significantly higher than that of the control group(P 0.001). DMS treatment significantly decreased the levels of serum ALT and AST at 6,12,and 24 h compared with that of the control group(P 0.01 for all). Serum HMGB1 levels at 6,12,and 24 h,as well as serum TNF-α,IL-6,and IL-1β levels at 12 h,were significantly lower in the DMS treatment group than in the control group(P 0.01 for all). Furthermore,hepatic inflammation,necrosis,and HMGB1 cytoplasm translocation in liver cells were significantly decreased in the DMS treatment group compared to the control group(43.72% ± 5.51% vs 3.57% ± 0.83%,χ2 = 12.81,P 0.01).CONCLUSION: Inhibition of Sph K1 ameliorates ALF by reducing HMGB1 cytoplasmic translocation in liver cells,and so might be a potential therapeutic strategy for this disease.     

Glycyrrhizic acid inhibits apoptosis and fibrosis in carbontetrachloride-induced rat liver injury

AIM:To investigate anti-apoptotic effects of glycyrrhizic acid(GA) against fibrosis in carbon tetrachloride(CCl4)-induced liver injury and its contributing factors.METHODS:Liver fibrosis was induced by administration of CCl4 for 8 wk.Pathological changes in the liver of rats were examined by hematoxylin-eosin staining.Collagen fibers were detected by Sirius red staining.Hepatocyte apoptosis was determined by TUNEL assay and the expression levels of cleaved caspase-3,Bax,α-SMA,connective tissue growth factor(CTGF),matrix metalloproteinase(MMP) 2 and MMP9 proteins were evaluated by western blot analysis,and α-SMA m RNA,collagen type Ⅰ and Ⅲ m RNA were estimated by real-time PCR.RESULTS:Treatment with GA significantly improved the pathological changes in the liver and markedly decreased the positive area of Sirius red compared with rats in the CCl4-treated group.TUNEL assay showed that GA significantly reduced the number of TUNEL-positive cells compared with the CCl4-treated group.The expression levels of cleaved caspase-3,Bax,α-SMA,CTGF,MMP2 and MMP9 proteins,and α-SMA m RNA,collagen type Ⅰ and Ⅲ m RNA were also significantly reduced by GA compared with the CCl4-treated group(P 0.05).CONCLUSION:GA treatment can ameliorate CCl4-induced liver fibrosis by inhibiting hepatocyte apoptosis and hepatic stellate cell activation.     

Human platelets inhibit liver fibrosis in severe combined immunodeficiency mice

AIM:To investigate the role of human platelets in liver fibrosis.METHODS:Severe combined immunodeficiency(SCID)mice were administered CCl4and either phosphate-buffered saline(PBS group)or human platelet transfusions(hPLT group).Concentrations of hepatocyte growth factor(HGF),matrix metallopeptidases(MMP)-9,and transforming growth factor-β(TGF-β)in the liver tissue were compared between the PBS and the hPLT groups by enzyme-linked immunosorbent assay(ELISA)and Western blotting.The effects of a human platelet transfusion on liver fibrosis included the fibrotic area,hydroxyproline content,and-smooth muscle actin(α-SMA)expression,which were evaluated by picrosirius red staining,ELISA,and immunohistochemical staining using an anti-mouse-SMA antibody,respectively.Phosphorylations of mesenchymal-epithelial transition factor(Met)and SMAD3,downstream signals of HGF and TGF-β,were compared between the two groups by Western blotting and were quantified using densitometry.Hepatocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling.Furthermore,the accumulation of human platelets in the liver 2 h after platelet transfusion was compared between normal and fibrotic livers by immunohistochemical staining using an anti-human CD41 antibody.RESULTS:The fibrotic area and hydroxyproline content in the liver were both significantly lower in the hPLT group when compared to the PBS group(fibrotic area,1.7%±0.6%vs 2.5%±0.6%,P=0.03;hydroxyproline content,121±26 ng/g liver vs 156±47 ng/g liver,P=0.04).There was less α-smooth muscle actin staining in the hPLT group than in the PBS group(0.5%±0.1%vs 0.8%±0.3%,P=0.02).Hepatic expression levels of mouse HGF and MMP-9were significantly higher in the hPLT group than in the PBS group(HGF,109±13 ng/g liver vs 88±22 ng/g liver,P=0.03;MMP-9,113%±7%/GAPDH vs 92%±11%/GAPDH,P=0.04).In contrast,the concentration of mouse TGF-β in the liver tissue was significantly lower in the hPLT group than in the PBS group(22±5ng/g liver vs 39±6 ng/g liver,P=0.     

Effects of tetrandrine on gastric mucosa and liver in portal hypertensive rats

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Impaired balance of T helper 17/T regulatory cells in carbon tetrachloride-induced liver fibrosis in mice

AIM:To investigate the effect of T helper(Th)17/T regulatory(Treg)cells on hepatic fibrosis in mice and its possible mechanism.METHODS:Hepatic fibrosis was induced by intraperitoneal injection of carbon tetrachloride.Hepatic pathological changes were observed by hematoxylin and eosin staining;the protein levels of interleukin(IL)-6,transforming growth factor(TGF)-βandα-smooth muscle actin(SMA)in liver tissue were determined by Western blotting;and the frequency of Th17 and Treg cells in the liver was estimated by flow cytometry.In addition,hepatic stellate cells were isolated from healthy mouse liver and co-cultured with Th17 or Treg cells.Immunofluorescence staining and Western blotting were performed to determine the change in HSC activation.RESULTS:In the model group,there were different degrees of fibroplasia,degeneration and necrosis.The protein levels of IL-6,TGF-βandα-SMA in liver tissue were significantly higher than those in the control group at 12 wk(P<0.05).Compared with the control group,the frequency of Th17 cells in the model group was increased but the frequency of Treg cells decreased gradually.Furthermore,at 4,8 and 12 wk,there were significant differences in the number of Th17 cells(0.52%±0.16%,1.46%±0.24%,and2.60%±0.41%,respectively,P<0.05)and Treg cells(2.99%±0.40%,2.16%±0.50%,and 1.49%±0.34%,respectively,P<0.05).In vitro,Th17 cells promoted,whereas Treg cells inhibited the expression ofα-SMA,both in a dose-dependent manner,compared with the control group.CONCLUSION:Th17/Treg imbalance exists in mice with liver fibrosis,which potentially promotes liver fibrosis via HSC activation.     

Bone marrow progenitor cells do not contribute to liver fibrogenic cells

AIM:To investigate the contribution of bone marrow(BM) cells to hepatic fibrosis.METHODS:To establish a model of chimerism,C57Bl/6 female mice were subjected to full-body irradiation(7 Gy) resulting in BM myeloablation.BM mononuclear cells obtained from male transgenic mice expressing enhanced green fluorescent protein(GFP) were used for reconstitution.Engraftment was confirmed by flow cytometry.To induce liver injury,chimeric animals received carbon tetrachloride(CCl4) 0.5 mL/kg intraperitoneally twice a week for 30 d(CCl4 30 d) and age-matched controls received saline(Saline 30 d).At the end of this period,animals were sacrificed for post mortem analysis.Liver samples were stained with hematoxylin and eosin to observe liver architectural changes and with Sirius red for collagen quantification by morphometric analysis.α-smooth muscle actin(α-SMA) was analyzed by confocal microscopy to identify GFP+ cells with myofibroblast(MF) characteristics.Liver tissue,BM and peripheral blood were collected and prepared for flow cytometric analysis using specific markers for detection of hepatic stellate cells(HSCs) and precursors from the BM.RESULTS:Injury to the liver induced changes in the hepatic parenchymal architecture,as reflected by the presence of inflammatory infiltrate and an increase in collagen deposition(Saline 30 d = 11.10% ± 1.12% vs CCl4 30 d = 12.60% ± 0.73%,P = 0.0329).Confocal microscopy revealed increased reactivity against α-SMA in CCl4 30 d compared to Saline 30 d,but there was no co-localization with GFP+ cells,suggesting that cells from BM do not differentiate to MFs.Liver flow cytometric analysis showed a significant increase of CD45+/GFP+ cells in liver tissue(Saline 30 d = 3.2% ± 2.2% vs CCl4 30 d = 5.8% ± 1.3%,P = 0.0458),suggesting that this increase was due to inflammatory cell infiltration(neutrophils and monocytes).There was also a significant increase of common myeloid progenitor cells(CD117+/CD45+) in the livers of CCl4-treated animals(Saline 30 d = 2.16% ± 1.80% vs CCl4 30 d = 5.60% ± 1.30%,P = 0.0142).In addition the GFP-/CD38+/CD45-subpopulation was significantly increased in the CCl4 30 d group compared to the Saline 30 d group(17.5% ± 3.9% vs 9.3% ± 2.4%,P = 0.004),indicating that the increase in the activated HSC subpopulation was not of BM origin.CONCLUSION:BM progenitor cells do not contribute to fibrosis,but there is a high recruitment of inflammatory cells that stimulates HSCs and MFs of liver origin.? 2012 Baishideng.All rights reserved.     

Prophylactic uses of integrin CD18-��A peptide in a murine polymicrobial peritonitis model

AIM: To evaluate the prophylactic properties of integrin CD18-βA peptide in a murine model of abdominal polymicrobial peritonitis and sepsis.METHODS: Bacterial sepsis was induced in Institute of Cancer Research (ICR) mice by cecal ligation and puncture (CLP) surgery. Inflicted mice were then injected with either sterile saline or CD18-βA peptide intraperitoneally at 2 h after surgery, and were sacrificed at 12 and 24 h after surgery. Blood samples were immediately collected, and analyzed for endotoxin activity and tumor necrosis factor (TNF)-α and interleukin (IL)-6. Lungs and liver were studied for CD45+ leukocyte and CD3 mRNA content. Pulmonary expression of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM) and E-selectin was also determined.RESULTS: Intraperitoneal injection of CD18-βA peptide significantly suppressed circulating endotoxin activity (P < 0.01) at 24 h, as well as serum levels of TNF-α (P < 0.05 at 12 and 24 h) and IL-6 (P < 0.01 at 12 h, P < 0.05 at 24 h) in CLP-inflicted mice. CD18-βA peptide also abrogated leukocyte infiltration into liver and lungs as unveiled by reduced CD45+ leukocyte and CD3 mRNA contents. Furthermore, the peptide significantly reduced pulmonary expression of VCAM (P < 0.01 at 12 h, P < 0.001 at 24 h), E-selectin (P < 0.01 at 12 and 24 h), and ICAM-1 (P < 0.01 at 12 h, P < 0.001 at 24 h). These actions of CD18-βA peptide collectively protected septic mice against lethality (P < 0.01).CONCLUSION: CD18-βA peptide is a potent endotoxin antagonist that can protect surgical patients against sepsis-associated lethality.     

Antifibrotic effect of N-acetyl-seryl-aspartyl-lysyl-proline on bile duct ligation induced liver fibrosis in rats

AIM:To investigate the preventive effect of N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) on bile duct ligation (BDL)induced liver fibrosis in rats. METHODS:Liver fibrosis in rats was induced by BDL and AcSDKP was infused subcutaneously for 2 wkvia a osmotic minipump (Alzet 2ML4) immediately after BDL operation. After scarifying, serum and liver specimens were collected. Hematoxylin and eosin staining, Sirius red staining, enzyme linked immunosorbent assay, Western blot or real-time polymerase chain reaction were used to determinate liver functions, histological alterations, collagen deposition, mRNA expression of markers for fibroblasts, transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-7 (BMP-7). RESULTS:When compared to model rats, chronic exogenous AcSDKP infusion suppressed profibrogenicTGF-β1 signaling, α-smooth muscle actin positivity (α-SMA), fibroblast specific protein-1 (FSP-1) staining and collagen gene expression. Col Ⅰ, Col Ⅲ, matrix metalloproteinase-2, tissue inhibitors of metallopro-teinase-1 and tissue inhibitors of metalloproteinase-2 mRNA expressions were all significantly downregulated by AcSDKP infusion (2.02 ± 1.10vs 14.16 ± 6.50, 2.02 ± 0.45vs 10.00 ± 3.35, 2.91 ± 0.30vs 7.83 ± 1.10, 4.64 ± 1.25 vs 18.52 ± 7.61, 0.46 ± 0.16 vs 0.34 ± 0.12, respectively, P 0.05). Chronic exogenous AcSDKP infusion attenuated BDL-induced liver injury, inflammation and fibrosis. BDL caused a remarkable increase in alanine transaminase, aspartate transaminase, total bilirubin, and prothrombin time, all of which were reduced by AcSDKP infusion. Mast cells, collagen accumulation, α-SMA, TGF-β1, FSP-1 and BMP-7 increased. The histological appearance of liver specimens was also improved. CONCLUSION:Infusion of exogenous AcSDKP attenu-ated BDL-induced fibrosis in the rat liver. Preservation of AcSDKP may be a useful therapeutic approach in the management of liver fibrosis.