Protection against hepatic ischemia/reperfusion injury via downregulation of toil-like receptor 2 expression by inhibition of Kupffer cell function

AIM: To elucidate the mechanism of liver protection by inhibition of Kupffer cells (KCs) function.METHODS: All the animals were randomly divided into three groups. Blockade group (gadolinium chloride solution (GdCl3) injection plus ischemia/reperfusion (I/R) injury):GdCl3 solution was injected once every 24 h for 2 d via the tail vein before I/R injury. Non-blockade group (saline solution injection plus I/R injury): saline instead of GdCl3 as a control was injected as in the blockade group. Sham group: saline was injected without I/R injury. Liver samples were collected 4 h after blood inflow restoration. The blockade of the function of KCs was verified by immunostaining with an anti-CD68 mAb. Toll-like receptor 2 (TLR2) was immunostained with a goat antimouse polyclonal anti-TLR2 antibody. Membrane proteins were extracted from the liver samples and TLR2 protein was analyzed by Western blot. Portal vein serum and plasma were taken respectively at the same time point for further detection of the levels of tumor necrosis factor-α (TNF-α) and alanine aminotransferase (ALT), an indicator of liver function.RESULTS: Compared to non-blockade group, CD68+ cells significantly reduced in blockade group (OPTDI, optical density integral): 32.97±10.55 vs 185.65±21.88,P＜0.01)and the liver function impairment was relieved partially (level of ALT: 435.89±178.37 U/L vs890.21±272.91 U/L,P＜0.01). The expression of TLR2 protein in blockade group significantly decreased compared to that in non-blockade group (method of immunohistochemistry, OPDTI: 75.74±17.44vs 170.58±-25.14, P＜0.01; method of Western blot,A value: 125.89±15.49 vs433.91±35.53, P＜0.01). The latter correlated with the variation of CD68 staining (r = 0.745,P＜0.05). Also the level of portal vein TNF-α decreased in blockade group compared to that in non-blockade group (84.45±14.73 ng/L vs112.32±17.56 ng/L, P＜0.05), but was still higher than that in sham group (84.45±14.73 ng/Lvs 6.07±5.33 ng/L, P＜0.01).CONCLUSION: Inhibition of the function of KCs may protect liver against I/R injury via downregulation of the expression of TLR2.     

Toll样受体参与小鼠肝脏缺血再灌注损伤

目的探讨Toll样受体是否参与小鼠肝脏缺血再灌注损伤及其机制. 方法用Toll样受体缺损小鼠(C3H/Hej,Hej组)和野生型(C3H/Heouj,Heouj组)小鼠复制部分肝脏缺血再灌注损伤模型,于缺血45min,再灌注1h和3h处死动物,检测血清天门冬氨酸氨基转移酶(AST)和血清肿瘤坏死因子α(TNFα)的含量;并以northern blot及髓过氧化物酶(MPO)试验分别检测缺血肝组织TNFα mRNA的表达和MPO的含量. 结果 (1)再灌注1、3h,与假手术组相比,小鼠血浆AST明显升高,但Hej组明显低于Heouj组(661.83U/L±106.09U/L和1215.5U/L±174.03U/L,t＝-6.65,P<0.01;1145.17U/L±132.43U/L和2958.17U/L±186.81U/L,t＝-5.57,P<0.01);(2)再灌注3h时,与假手术组相比,Hej组和Heouj组小鼠血清TNFα浓度明显升高,且前者明显低于后者(152.39pg/ml±43.3pg/ml和249.12pg/ml±51.89pg/ml,t＝-3.13,P<0.05);(3)再灌注1h,除假手术组外,Hej组和Heouj组小鼠缺血肝组织内可见TNFα mRNA的表达,但前者的表达水平明显低于后者,杂交带密度分析显示两者之间差异有显著性 (80.3±28.8与189.4±24.6,t＝-3.25,P<0.05);(4)再灌注3h,与假手术组相比,Hej组和Heouj组小鼠缺血肝组织内MPO含量明显升高,且前者含量明显低于后者(0.059±0.004和0.173±0.025,F＝33.49,P<0.01). 结论 Toll样受体可能通过其介导的炎性通路参与了小鼠肝脏缺血再灌注损伤.     

Gender differences in hepatic ischemic reperfusion injury in rats are associated with endothelial cell nitric oxide synthase-derived nitric oxide

AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated with endothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO). METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissue malondialdehyde (MDA) content, and severity of hepatic I/R injury. RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs45.3μ10.1 μmol/L, P<0.01). Although serum NO levels decreased significantly after hepatic I/R (P<0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P<0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs668.7±78.7 U/L, 1.71±0.18μg/L and 0.86±0.11 μmol/g, respectively, P<0.01). I/R induced significant injury to the liver both in M and F groups (P<0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P<0.05 and P<0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P<0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β-estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P<0.01). The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P<0.01 and P<0.05). The NOS inhibitor Nw-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOS-derived NO.     

Protection of Veratrum nigrum L. var. ussuriense Nakai alkaloids against ischemia-reperfusion injury of the rat liver

AIM： TO investigate the protective effects and possible mechanisms of Veratrum nigrum L. var. ussuriense Nakai alkaloids （VnA） on hepatic ischemia/reperfusion （I/R） injury in rats.
METHODS： Forty male Wistar rats were randomly divided into four experimental groups （n = 10 in each）： （A） Control group （the sham operation group）; （8） I/R group （pretreated with normal saline）; （C） Small-dose （10 μg/kg） VnA pretreatment group; （D） Large-dose （20 μg/kg） VnA pretreatment group. Hepatic ischemia/ reperfusion （Hepatic I/R） was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase （SOD） activity, myeloperoxidase （MPO） activity and nitric oxide （NO） content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 （ICAM-1） and E-selectin （ES） were detected by immunohistochemical examinations and Western blot analyses.
RESULTS： The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase （ALT： 74.53 ± 2.58 IU/L vs 1512.54 ± 200.76 IU/L, P 〈 0.01） and lactic dehydrogenase （LDH： 473.48 ± 52.17 IU/L vs 5821.53 ± 163.69 IU/L, P 〈 0.01）, as well as the levels of MPO （1.97 ± 0.11 U/g vs 2.57 ± 0.13 U/g, P 〈 0.01） and NO （69.37 ± 1.52 μmol/g protein vs 78.39 ± 2.28 μmol/g protein, P 〈 0.01） in the liver tissue, all of which were reduced by pretreatment with VnA, respectively （ALT： 1512.54 ± 200.76 IU/L vs 977.93 ± 89.62 IU/L, 909.81 ± 132.76 IU/L, P 〈 0.01, P 〈 0.01; LDH： 5821.53 ± 163.69 IU/L vs 3015.44 ± 253.01 IU/L, 2448.75 ± 169.4 IU/L, P 〈 0.01, P 〈 0.01; MPO： 2.57 ± 0.13 U/g vs 2.13 ± 0.13 U/g,     

Heme oxygenase-1 induction by hemin protects liver cells from ischemia/reperfusion injury in cirrhotic rats

AIM： To investigate the potential protective effect of HO-1 on cirrhotic liver cells in rats.
METHODS： Male Wistar rats included in the current study were randomly divided into 5 groups as follows： normal （N） group; liver cirrhotic （LC） group; sham （S） group; I/R group and I/R ＋ hemin group. The model for inducing liver cirrhosis in rats was established according to a previously published protocol. Following this the segmental hepatic ischemia reperfusion operation was carried out. The rats were treated with 30 l~mol/kg hemin （HO-1 inducer, ferric portoporphyrin IX chloride） i.p. or 0.9% NaCI （control） 24 h and 12 h before hepatic ischemia for 30 min or sham laparotomy. Blood was collected for serum enzymatic measurement 6 and 12 h after reperfusion or sham laparotomy. HO-1, NF-κB and caspase-3 expressions were assessed by immunohistochemical analysis.
RESULTS： The expressions of proteins are inversely correlated to the gray values. HO-1 expression in the I/R ＋ hemin group was increased significantly than I/R group at 6 h and 12 h after hepatic I/R （6 h： 112.0± 8.3 vs 125.1± 5.7, P 〈 0.01; 12 h： 120.8± 11.0 vs 132.4 ± 6.2, P 〈 0.01）. Hemin improved serum manganese superoxide dismutase （MnSOD） （6 h： 131.3 ± 17.6 vs 107.0 ± 13.9, P 〈 0.01; 12 h： 141.4 ：E 12.5 vs 118.3± 10.2, P 〈 0.01）, lessened liver cell injury, decreased caspase-3（6 h： 166.7 ± 8.1 vs 145.5 ± 14.6, P 〈 0.01; 12 h： 172.8± 3.8 vs 148.0 ±6.5, P 〈 0.01） and NF-κB expression （6 h： 150.2 ± 8.6 vs 139.7 ±6.0, P 〈 0.01; 12 h： 151.1 ± 5.9 vs 148.1± 5.3, P 〉 0.05） and serum alanine aminotransferase （ALT） （6 h： 413.3± 104.1 vs 626.8 ±208.2, P 〈 0.01; 12 h： 322.2 ± 98.8 vs 425.8 ± 115.4, P 〈 0.05）, aspartate aminotransferase （AST） （6 h： 665.2 ± 70.1 vs 864.3± 70.4, P 〈 0.01; 12 h： 531.1 ± 98.6 vs 664.4± 115.6, P 〈 0.01）, malondialdehyde （MDA） levels （6 h： 11.1 ± 2.17 vs 13.5 ±2.01, P 〈 0.01; 12 h： 9.36     

Leptin administration exacerbates thioacetamide-induced liver fibrosis in mice

AIM: To investigate the effects of leptin administration on liver fibrosis induced by thioacetamide (TAA). METHODS: Twenty-four male C57Bl/6 mice were randomly allocated into four groups, which were intra-peritoneally given saline (2 mL/kg), leptin (1 mg/kg), TAA (200 mg/kg), TAA (200 mg/kg) plus leptin (1 mg/kg) respectively, thrice a week. All mice were killed after 4 wk. The changes in biochemical markers, such as the levels of alanine aminot-ransferase (ALT) and aspartate aminotransferase (AST) in serum and superoxide dismutase (SOD), malondialdehyde (MDA) in liver were determined. For histological analysis, liver tissues were fixed with 10% buffered formalin, embedded with paraffin. Hematoxylin-eosin (HE) staining and picric acid-Sirius red dyeing were performed. The level of α1(I) procollagen mRNA in liver tissues was analyzed by RT-PCR. RESULTS: Apparent liver fibrosis was found in TAA group and TAA plus leptin group. Compared to saline group, the levels of ALT and AST in serum and MDA in liver increased in TAA group (205.67±27.69 U/L vs50.67±10.46 U/L, 177.50±23.65 U/L vs 76.33±12.27 U/L, 2.60±0.18 nmol/mg pro vs 1.91±0.14 nmol/mg pro, P<0.01) and in TAA plus leptin group (256.17±22.50 U/L vs 50.67±10.46 U/L, 234.17±27.37 U/L vs 76.33±12.27 U/L, 2.97±0.19 nmol/mg pro vs 1.91±0.14 nmol/mg pro,P<0.01). The level of SOD in livers decreased (51.80±8.36 U/mg pro vs 81.52±11.40 U/mg pro, 35.78±6.11 U/mg pro vs 81.52± 11.40 U/mg pro, P<0.01) and the level of α1(I) procollagen mRNA in liver tissues also increased (0.28±0.04 vs 0.11± 0.02, 0.54±0.07 vs 0.11±0.02, P<0.01). But no significant changes were found in leptin group and saline group. Compared to TAA group, ALT, AST, MDA, and α1(I) procollagen mRNA and grade of liver fibrosis in TAA plus leptin group increased (256.17±22.50 U/L vs 205.67± 27.69 U/L, P<0.05; 234.17±27.37 U/L vs 177.50±23.65 U/L, P<0.05; 2.97±0.19 nmol/mg pro vs 2.60±0.18 nmol/mg pro,P<0.05; 0.54±0.07 vs 0.28±0.04, P<0.01; 3.17 vs 2.00, P<0.05), and the level of SOD in liver decreased (35.78±6.11 U/mg pro vs 51.80±8.36 U/mg pro, P<0.05). There were similar changes in the degree of type I collagen deposition confirmed by picric acid-Sirius red dyeing. CONCLUSION: Leptin can exacerbate the degree of TAA-induced liver fibrosis in mice. Leptin may be an important factor in the development of liver fibrosis.     

Expression of toll-like receptor 4 and MD-2 gene and protein in Kupffer cells after ischemia-reperfusion in rat liver graft

AIM: To investigate the expression of toll-like receptor 4 (TLR4) and MD-2 gene and protein in Kupffer cells (KCs) and their role in ischemia-reperfusion (IR) injury of rat liver graft. METHODS: KCs were isolated at 0 (control group), 2, 12, 24 h (IR group) following IR in rat liver graft. mRNA expression of TLR4 and MD-2 was detected by RT-PCR analysis, protein expression of TLR4/MD-2 was detected by flow cytometric (FCM) analysis, and tumor necrosis factor-alpha (TNF-alpha) level in supernatant was measured by ELISA. Then isolated KCs were incubated with anti-TLR4 polyclonal antibody (anti-TLR4 group), and TNF-alpha level was measured again. RESULTS: The mRNA and protein expression of TLR4/MD-2 and the level of TNF-alpha in IR group increased significantly at 2 h following IR, and reached the maximum at 12 h, and slightly decreased at 24 h, but were still significantly higher than those in the control group (P<0.01). The expression of these factors was markedly decreased after anti-TLR4 antibody treatment as compared with the IR group (P<0.01). CONCLUSION: Lipopolysaccharide (LPS) following IR can up-regulate TLR4/MD-2 gene and protein expression in KCs, and synthesize cytokine TNF-alpha. Anti TLR4 antibody can inhibit the production of TNF-alpha induced by LPS. TLR4 and its partner molecule MD-2 may play an important role in Kupffer cell activation and IR injury.     

GdCl_3 abates hepatic ischemia-reperfusion injury by inhibiting apoptosis in rats

BACKGROUND:Gadolinium chloride(GdCl3)is a specific inhibitor of Kupffer cells(KCs),which are important promoters of various liver injuries.It is therefore of interest to explore the role of KCs in liver ischemia-reperfusion injury and their relations with apoptosis caused by ischemia-reperfusion injury. METHODS:One hundred male Wistar rats(190-210 g, 6-7 weeks old)were divided into two groups at random, GdCl3 group and control group.Samples were collected at 0.5,1,6,12,and 24 hours from each group after rep...     

Role of Kupffer cells in acute hemorrhagic necrotizing pancreatitis-associated lung injury of rats

AIM:To investigate the role of Kupffer cells(KCs)inacute hemorrhagic necrotizing pancreatitis-associatedlung injury(AHNP-LI).METHODS:Forty-two rats were allocated to fourgroups[sham operation,AHNP model,gadoliniumchloride(GdCl_3)pretreatment,GdCl_3 control].In GdCl_3pretreatment group,GdCl_3 was administered by caudalvein injection 24 h before the AHNP model induction.Blood from the iliac artery,alveolar macrophages andtissues from the pancreas and lung,were collected insix animals per group 3 and 6 h after acute pancreatitisinduction.TNF-α,IL-1 of serum,myeloperoxidase(MPO)of lung tissue,NF-kB activation of alveolar macrophageswere detected.Serum AST and ALT in sham operationgroup and GdCl_3 control group were tested.In addition,histopathological changes of the pancreas and lung wereobserved under light microscope.RESULTS:MPO of lung tissue and TNF-α,IL-1 levelsof serum were all reduced significantly in GdCl_3pretreatment group compared to those in AHNP group(P<0.01).NF-kB activation of alveolar macrophageswas also attenuated significantly in GdCl_3 pretreatmentgroup compared to that in AHNP group(P<0.01).Thepathological injury of the lung was ameliorated obviouslyin GdCl_3 pretreatment group compared to that in AHNPgroup.Nevertheless,the serum amylase level did notreduce and injury of the pancreas was not prevented inGdCl_3 pretreatment group.CONCLUSION:Pulmonary injury induced by AHNPis mediated by KC activation and AHNP-LI can be significantly ameliorated by pretreatment with GdCl_3 andKCs play a vital role in AHNP-LI.     

Nuclear factor-kappaB decoy oligodeoxynucleotides attenuates ischemia/reperfusion injury in rat liver graft

AIM: To evaluate the protective effect of NF-kappaB decoy oligodeoxynucleotides (ODNs) on ischemia/reperfusion (I/R) injury in rat liver graft. METHODS: Orthotopic syngeneic rat liver transplantation was performed with 3 h of cold preservation of liver graft in University of Wisconsin solution containing phosphorothioated double-stranded NF-kappaB decoy ODNs or scrambled ODNs. NF-kappaB decoy ODNs or scrambled ODNs were injected intravenously into donor and recipient rats 6 and 1 h before operation, respectively. Recipients were killed 0 to 16 h after liver graft reperfusion. NF-kappaB activity in the liver graft was analyzed by electrophoretic mobility shift assay (EMSA). Hepatic mRNA expression of TNF-alpha, IFN-gamma and intercellular adhesion molecule-1 (ICAM-1) were determined by semiquantitative RT-PCR. Serum levels of TNF-alpha and IFN-gamma were measured by enzyme-linked immunosorbent assays (ELISA). Serum level of alanine transaminase (ALT) was measured using a diagnostic kit. Liver graft myeloperoxidase (MPO) content was assessed. RESULTS: NF-kappaB activation in liver graft was induced in a time-dependent manner, and NF-kappaB remained activated for 16 h after graft reperfusion. NF-kappaB activation in liver graft was significant at 2 to 8 h and slightly decreased at 16 h after graft reperfusion. Administration of NF-kappaB decoy ODNs significantly suppressed NF-kappaB activation as well as mRNA expression of TNF-alpha, IFN-gamma and ICAM-1 in the liver graft. The hepatic NF-kappaB DNA binding activity [presented as integral optical density (IOD) value] in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (2.16+/-0.78 vs 36.78+/-6.35 and 3.06+/-0.84 vs 47.62+/- 8.71 for IOD value after 4 and 8 h of reperfusion, respectively, P<0.001). The hepatic mRNA expression level of TNF-alpha, IFN-gamma and ICAM-1 [presented as percent of beta-actin mRNA (%)] in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (8.31+/-3.48 vs 46.37+/-10.65 and 7.46+/- 3.72 vs 74.82+/-12.25 for hepatic TNF-alpha mRNA, 5.58+/-2.16 vs 50.46+/-9.35 and 6.47+/-2.53 vs 69.72+/-13.41 for hepatic IFN-gamma mRNA, 6.79+/-2.83 vs 46.23+/-8.74 and 5.28+/-2.46 vs 67.44+/-10.12 for hepatic ICAM-1 mRNA expression after 4 and 8 h of reperfusion, respectively, P<0.001). Administration of NF-kappaB decoy ODNs almost completely abolished the increase of serum level of TNF-alpha and IFN-gamma induced by hepatic ischemia/reperfusion, the serum level (pg/mL) of TNF-alpha and IFN-gamma in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (42.7+/-13.6 vs 176.7+/-15.8 and 48.4+/-15.1 vs 216.8+/-17.6 for TNF-alpha level, 31.5+/-12.1 vs 102.1+/-14.5 and 40.2+/-13.5 vs 118.6+/-16.7 for IFN-gamma level after 4 and 8 h of reperfusion, respectively, P<0.001). Liver graft neutrophil recruitment indicated by MPO content and hepatocellular injury indicated by serum ALT level were significantly reduced by NF-kappaB decoy ODNs, the hepatic MPO content (A655) and serum ALT level (IU/L) in the NF-kappaB decoy ODNs treatment group rat was significantly lower than that of the I/R group rat (0.17+/-0.07 vs 1.12+/-0.25 and 0.46+/-0.17 vs 1.46+/-0.32 for hepatic MPO content, 71.7+/-33.2 vs 286.1+/-49.6 and 84.3+/-39.7 vs 467.8+/-62.3 for ALT level after 4 and 8 h of reperfusion, respectively, P<0.001). CONCLUSION: The data suggest that NF-kappaB decoy ODNs protects against I/R injury in liver graft by suppressing NF-kappaB activation and subsequent expression of proinflammatory mediators.     

Blockage of transforming growth factor β receptors prevents progression of pig serum-induced rat liver fibrosis

AIM: To test the hypothesis that introduction of antisense TβR Ⅰ and TβR Ⅱ eukaryotic expressing plasmids into a rat model of immunologically induced liver fibrosis might block the action of TGF-β1 and halt the progression of liver fibrosis. METHODS: RT-Nest-PCR and gene recombination techniques were used to construct rat antisense TβR Ⅰ and TβR Ⅱ recombinant plasmids which could be expressed in eukaryotic cells. The recombinant plasmids and empty vector (pcDNA3) were encapsulated by glycosyl-poly-L-lysine and then transducted into rats of pig serum-induced liver fibrosis model. Expression of exogenously transfected gene was assessed by Northern blot, and hepatic expressions of TβR Ⅰ and TβR Ⅱ were evaluated by RT-PCR and Western blot.We also performed ELISA for serum TGF-β1, hydroxyproline of hepatic tissues, immunohistochemistry for collagen types Ⅰ and Ⅲ, and VG staining for pathological study of the liver tissues. RESULTS: The exogenous antisense TβR Ⅰ and TβR Ⅱ plasmids could be well expressed in vivo, and block mRNA and protein expression of TβR Ⅰ and TβR Ⅱ in the fibrotic liver at the level of mRNA respectively. These exogenous plasmid expressions reduced the level of TGF-β1 (antisense TβR Ⅰ group 23.998+3.045 ng/mL, antisense TβR Ⅱ group 23.156+3.131 ng/mL, disease control group 32.960+3.789 ng/mL; F-=-38.19, 36.73, P&lt;0.01). Compared with disease control group, the contents of hepatic hydroxyproline (antisense TβR Ⅰ group 0.169+0.015 mg/g liver, antisense TβR Ⅱ group 0.167+0.009 mg/g liver, disease control group 0.296+0.026 mg/g liver; F=14.39, 15.48, P&lt;0.01) and the deposition of collagen types Ⅰ and Ⅲ decreased in the two antisense treatment groups(antisense TβR Ⅰ group, collagen type Ⅰ 669.90+50.67, collagen type Ⅲ 657.29+49.48; antisense TβR Ⅱ group, collagen type Ⅰ 650.26+51.51, collagen type Ⅲ 661.58+55.28; disease control group, collagen type I 1209.44+116.60, collagen type Ⅲ 1175.14+121.44; F=15.48 to 74.89, P&lt;0.01). Their expression also improved the pathologic classification of liver fibrosis models (compared with disease control group, X^2=17.14, 17.24, P&lt;0.01). No difference was found in the level of TGF-β1, the contents of hepatic hydroxyproline and collagen types Ⅰ and Ⅲ and pathologic grade between pcDNA3 control group and disease control group or between the two antisense treatment groups (F=0.11 to1.06, X^2=0.13 to 0.16, P&gt;0.05). CONCLUSION: Antisense TβR Ⅰ and TβR Ⅱ recombinant plasmids have certain reverse effects on liver fibrosis and can be used as possible candidates for gene therapy.     

Inhibitory effect of Huangqi Zhechong decoction on liver fibrosis in rat

AIM: To assess the inhibitory effect of Huangqi Zhechong decoction on hepatic fibrosis in rats induced by CCl(4) plus alcohol and high fat low protein diet. METHODS: Male SD rats were randomly divided into hepatic fibrosis model group, control group and 3 treatment groups consisting of 12 rats in each group. Except for the normal control group, all the rats were subcutaneously injected with CCl(4) at a dosage of 3 mL/kg. In 3 treated groups, either high-dose group (9 mL/kg), or medium-dose group (6 mL/kg), or low-dose group (3 mL/kg) was daily gavaged with Huangqi Zhechong decoction, and saline vehicle was given to model and normal control rats. Enzyme-linked immunosorbent assay (ELISA) and biochemical examinations were used to determine the changes of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hyaluronic acid (HA), laminin (LN), type-III-procollagen-N-peptide (PIIIP), and type IV collagen content in serum, and hydroxyproline (Hyp) content in liver after sacrificing the rats. Pathologic changes, particularly fibrosis were examined by hematoxylin and eosin (HE) and Van Gieson staining. RESULTS: Compared with the model control group, serum ALT, AST, HA, LN, PIIIP and type IV collagen levels dropped markedly in Huangqi Zhechong decoction groups, especially in the medium-dose Huangqi Zhechong decoction group (1 954+/-576 U/L vs 759+/-380 U/L, 2 735+/-786 U/L vs 1 259+/-829 U/L, 42.74+/-7.04 ng/mL vs 20.68+/-5.85 ng/mL, 31.62+/-5.84 ng/mL vs 14.87+/-1.45 ng/mL, 3.26+/-0.69 ng/mL vs 1.47+/-0.46 ng/mL, 77.68+/-20.23 ng/mL vs 25.64+/-4.68 ng/mL, respectively) (P<0.05). The Hyp content in liver tissue was also markedly decreased (26.47+/-11.24 mg/mgprot vs 9.89+/-3.74 mg/mgprot) (P<0.01). Moreover, the stage of the rat liver fibrosis in Huangqi Zhechong decoction groups was lower than that in model group, and more dramatic drop was observed in medium-dose Huangqi Zhechong decoction group (P<0.01). CONCLUSION: Huangqi Zhechong decoction can inhibit hepatic fibrosis resulted from chronic liver injure, retard the development of cirrhosis, and notably ameliorate the liver function. It may be a safe and effective therapeutic drug for patients with fibrosis.     

甘氨酸对内毒素性肝损害保护作用的实验研究

目的探讨甘氨酸(Gly)对内毒素(LPS)性肝损害的保护机制。方法BABL／c小鼠随机分为两组,LPS组经腹腔注射10 mg／kg的LPS,Gly组在注射相同剂量LPS前3 d开始喂饲含5％Gly的饲料。光镜观察组织病理学改变、免疫组织化学法检测Toll样受体4(TLR4)表达水平；酶联免疫吸附法检测血浆肿瘤坏死因子(TNF)α、白细胞介素10(IL-10)浓度及逆转录聚合酶链反应检测肝组织中TNFα、IL-10及TLR4的mRNA表达水平。结果Gly能明显提高小鼠存活率,肝脏病理损害程度减轻；Gly组TNFα水平显著低于LPS组,差异有统计学意义[(1852.80±126.64)pg／ml对(708.83±51.29)pg／ml,P＜0.05]；Gly组IL-10增加且高峰前移,与LPS组比较差异有统计学意义[(418.64±38.86)pg／ml对(344.09±31.70)pg／ml,P＜0.05]；Gly组肝组织中TNFα及TLR4表达也明显减弱,IL-10表达明显增强,与LPS组比较差异均有统计学意义[分别为TNFα：A值1.59±0.14对0.91±0.11；TLR4：A值0.97±0.12对0.53±0.11；IL-10：A值0.62±0.08对1.06±0.15；P值均＜0.05]。结论Gly能明显减轻LPS所致的肝损害,其机制可能与其下调肝脏各种细胞的TLR4表达,同时上调IL-10的水平有关。     

Immunologic role of nitric oxide in acute rejection of golden hamster to rat liver xenotransplantation

AIM：To evaluate the immunologic role and expression significances of nitric oxide(NO),nitric oxide synthase(NOS),and its isoenzyme in acute erjection to liver xenografts from golden hamster in rat.METHODS:Liver transplantations were randomly divided into five groups(n=6-9):isografts(groupⅠ）;xenografts(groupⅡ）;xenografts plus cyclosporing teatment(groupⅢ）,xenografts plus cyclophosphamide treatment combined with splenectomy(groupⅣ）,and xenografts using cyclophosphamide in combination with splenectomy(groupⅣ）and xenografts using splenectomy in addition to cyclophosphamide and cyclosporine treatments(groupⅤ）.The levels of ALT,TNF-α,and nitric oxide production(NOx)in serum of reciprents were examined,and expressions of typeⅡ（iNOS)and typeⅢ（nitric oxide synthase(NOS)-inducibleNOS(iNOS)and constitutive NOS(cNOS)were observe by NADPH digphorase histochemical and immunohistochemical staining.RESULTS:The level of serum ALT,activity of serum TNF-αand systemic levels of NO metabolite in groups ⅡandⅣwere higher than those of groupsⅠandⅤ(serumALT,2416&#177;475,2540&#177;82.5)nkat&#183;L^-1vs（556.8&#177;43.5,677.30&#177;38.2)nkat&#183;L^-1,P&lt;0.01,(serumTNF-α,353.5&#177;16.1,444.6&#177;28.1)ng&#183;L^-1,vs38.5&#177;5.2,52.0&#177;5.7)ng&#183;L^-1,P&lt;0.01,(serum NOx514.6&#177;18.1,336.0&#177;43.0)nmol&#183;g^-1,vs26.1&#177;5.7,27.7&#177;6.0)nmol&#183;g^-1,P&lt;0.01.Cyclosporine in groupⅢcan repress the cellular immune response and the synthesis of nitric oxide and the expression of NO synthase,but not prolong the lives xenograft survival.The over-expression of NOS,iNOS and cDNA in liver xenograft rejection in groupsⅡandⅣwere detected by NADPH diaphorase histochemical and immunohistochemical staining.CONCLUSION:The degrees of acute rejection can be effectively repressed in golden hamster to rat liver xenografts with splenectomy and cyclosporin,Nitric oxide metabolites,and nitric oxide synthase and its isoenzymes,above all inducibleNOS(iNOS)can be used as potential diagnostic markers for acute rejection in liver transplantation.The cellular localization of nit6ric oxide varies according to the immunologic status of liver xenografts.thus thinking that hepatocyte derived nitric oxide may be protective in the hyporesponsive state,but hepatic injury is likely triggered by centrilobular iNOS expression in the superresponsive state.     

库普弗细胞Toll样受体2在小鼠肝脏缺血再灌注损伤中的表达及意义

目的探索库普弗细胞Toll样受体2(TLR2)在肝脏缺血再灌注损伤中的表达变化,分析库普弗细胞TLR2信号通路参与肝脏缺血再灌注损伤的机制。方法动物分假手术对照(SH)组、缺血再灌注(I/R)组及氯化钆处理(Gd)组,复制小鼠肝脏部分缺血1 h再灌注4 h损伤模型,结束再灌注后,取缺血叶肝脏组织及其库普弗细胞,提取总RNA及膜蛋白质分析TLR 2 mRNA及蛋白的表达,同时提取缺血肝叶组织核蛋白分析核因子(NF—κB),并检测门静脉血中肿瘤坏死因子(TNF α)、丙氨酸氨基转移酶(ALT) 及内毒素水平。结果再灌注4 h,(1)I/R组缺血肝叶TLR2 mRNA及蛋白表达水平较SH组高,△Ct值分别为1.06±0.91和5.08±1.32,t=7.80,P<0.01;A值分别为433.91±25.53和102.86±13.58,t=28.04, P<0.01。Gd组缺血肝叶TLR2 mRNA及蛋白表达水平较I/R组下降,△Ct值分别为4.22±0.84和1.06±0.91,t=7.56,P<0.01;A值分别为125.89±15.49和433.91±25.53,t=25.27,P<0.01。(2)I/R组缺血肝叶库普弗细胞中TLR2 mRNA及蛋白表达水平较SH组高,△Ct值分别为0.52±0.23和2.61±0.1 8, t=17.47,P<0.01;A值分别为379.70±34.16和114.98±21.90,t=15.98,P<0.01。Gd组缺血肝叶库普弗细胞中TLR2 mRNA及蛋白表达水平则较I/R组下降,△Ct值分别为1.90±0.14和0.52±0.23,t= 12.     

Intestinal damage mediated by Kupffer cells in rats with endotoxemia

AIM：To determine the in vivo effects of phagocytic blockade of Kupffer cell(KC)on the release of proinflammatory cytokines in small intestinal lesion and on the integrity of intestinal tract by using gadolinium chloride(GdCl3)during early endotoxemia.METHODS:Wistar rats were divided into three groups:GropA,rats were injected with endotoxin(E.coliO111:B4,adose of 12mg&#183;kg^-1)only;GroupB,rats were pretreated intravenously with 25mg of GdCl3per kg24hare given endotoxin;and Group C,sham operation only.All animals were sacrificed 4h after endotoxin injecton.In portion of the rats of three groups.bile duct was cannulated,which the bile was collected externally.Morphological changes of ileum were observed under light microscopy and electronic microscopy.The KC were isolated rfrom rats by collagenase perfusion and inKC,expression of TNF-αand IL-6mRNA were determined by RT-PCRanalysis.Plasma and bile TNF-αandIL-6Levels were determined by enzyme-linked immunosorbent assay(EISA)&gt;RESULTS:In group A,there were neutrophil infiltration and superficial epitelial necrosis of the ilealvvilli,sloughing of mucosal epithelium.and disappear ance of somevilli.In groupB.the ileal mucosal damage was much reduced.which in groupC,no significant morphological changes were seen,GdCl3pretreatment decreased significantly the expression of TNF-αand IL-6mRNA ingroupB(4.32&#177;0.47and4.05&#177;0.43)when compared to groupA(9.46&#177;1.21and9.04&#177;1.09)(P&lt;0.05).There was no significant expression of TNF-αand IL-6mRNA in groupC(1.03&#177;0.14and10.4&#177;0.13).In rats of groupA,the levels of TNF-αand IL-6in bile and plasma were 207&#177;29ng&#183;L^-1,1032&#177;107ng&#183;L^-1,213&#177;33ng&#183;L^-1,and 1185&#177;127ng&#183;L^-1,respectively.In groupB,they were113&#177;18ng&#183;L^-1,repectively.In groupC,they were 67&#177;10ng&#183;L^-1,72&#177;13ng&#183;L^-1,109&#177;18ng&#183;L^-1,and 118&#177;22ng&#183;L^-1respectively.There were significant difference between the three group(P&lt;0.05).CONCLUSION:KC release cytokinesTNF-αand IL-6causing damage to the integrity of intestinal epithelium and play a crucial role in the initiation and progression of intestinal mucosal damage during early endotoxemia.     

Blockade of Kupffer cells by gadolinium chloride reduces lipid peroxidation and protects liver from ischemia/reperfusion injury

BACKGROUND/AIMS: The implication of lipid peroxidation in the inhibitory effect of GdCl3 (gadolinium chloride) on Kupffer cells activation has not been extensively investigated. The aim of this study was to examine the effect of GdCl3 inhibition of Kupffer cells activation on lipid peroxidation after severe total hepatic ischemia/reperfusion. METHODOLOGY: Male Wistar rats (n = 40) were randomly divided into a sham-operation group, a control ischemia/reperfusion group, and two ischemia/reperfusion groups pretreated with GdCl3 (10 mg and 20 mg/kg bw intravenously, 48 and 24 h prior to operation). Following 60 min of total hepatic ischemia and 120 min of reperfusion, the rats were sacrificed, and liver samples were taken for determination of malondialdehyde and light microscopy examination. Blood samples were also taken for assay of aspartate and alanine transaminase. Additional animals (n = 60) were followed up for a 7-day survival rate determination. RESULTS: Ischemia/reperfusion decreased the survival rate to 13.3%, increased (p < 0.001) the levels of aspartate and alanine transaminase in serum to 2387 +/- 75 and 2157 +/- 87 IU/L, respectively, and increased (p < 0.001) malondialdehyde levels in liver to 1.609 +/- 0.096 nmoles/g compared with 1.164 +/- 0.060 in the sham operation group. Pretreatment with GdCl3 increased the survival rate to 60%, and decreased (p < 0.001) the levels of aspartate transaminase in serum to 1549 +/- 66 and 1496 +/- 55 IU/L, the levels of alanine transaminase in serum to 1302 +/- 48 and 1305 +/- 63 IU/L, and the levels of malondialdehyde in liver to 1.132 +/- 0.034 and 1.149 +/- 0.57 nmoles/g for the lower and the higher doses of GdCl3, respectively. Histological examination showed protection of liver parenchyma in the animals treated with GdCl3. CONCLUSIONS: Experimental data suggest that GdCl3 inhibition of Kupffer cells activation protects liver from ischemia/reperfusion injury by a mechanism that reduces lipid peroxidation.