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.

Pyrrolidine dithiocarbamate alleviates the anti-tuberculosis drug-induced liver injury through JAK2/STAT3 signaling pathway:An experimental study

Objective:To study the effect of pyrrolidine dithiocarbamate(PDTC) on the anti-tuberculosis drug-induced liver injury and the molecular mechanism. Methods:Clean male SD rats were selected as experimental animals and randomly divided into normal group,model group,PDTC group and AG490 group. Animal model of anti-tuberculosis drug-induced liver injury was established by intragastric administration isoniazid + rifampicin. PDTC group received intraperitoneal injection of PDTC,and AG490 group received intraperitoneal injection of AG490. Twenty-eight days after intervention,the rats were executed,and the liver injury indexes,inflammation indexes and oxidative stress indexes in serum as well as JAK2/STAT3 expression,liver injury indexes,inflammation indexes and oxidative stress indexes in liver tissue were determined. Results:p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissue as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of model group were significantly higher than those of normal group while p-JAK2,p-STAT3,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA expression in liver tissu as well as TBIL,ALT,AST,γ-GT,TNF-α,IL-1β,IL-6,ROS,8-OHdG and MDA levels in serum of PDTC group and AG490 group were significantly lower than those of model group. Conclusions:PDTC can inhibit the inflammation and oxidative stress mediated by JAK2/STAT3 signaling pathway to alleviate the anti-tuberculosis drug-induced liver injury.

Immune formulation-assisted conventional therapy on anti-infective effectness of multidrug-resistant Mycobacterium tuberculosis infection mice

Objective:To study the effect of immune formulation-assisted conventional therapy on antiinfective ability of multidrug-resistant Mycobacterium tuberculous infection mice.Methods:BALB/c mice were used as experimental animals,multidrug-resistant Mycobacterium tuberculosis infection models were built,randomly divided into model group,moxifloxacin group,thymopentin group and combined treatment group and given corresponding drug intervention,and then colony numbers in the spleen and lung,T lymphocyte subset contents and programmed death-1(PD-1) expression levels in peripheral blood were detected.Results:Colony numbers in lung and spleen of moxifloxacin group and thymopentin group were significantly lower than those of model group and colony numbers in lung and spleen of combined treatment group were significantly lower than those of moxifloxacin group and thymopentin group:contents of CD3^+CD4^+T cells,Thl and Thl7 in peripheral blood of moxifloxacin group and thymopentin group were higher than dtose of model group,and contents of CD3^+CD8^+T cells.Th2 and Treg were lower than those of model group;contents of CD3^+CD4^+T cells.Th 1 and Th 17 in peripheral blood of combined treatment group were higher than those of moxifloxacin group and thymopentin group,and contents of CD3^+CD8^+T cells.Th2 and Treg were lower than those of moxifloxacin group and thymopentin group:PD-I expression levels on T lymphocyte,B lymphocyte and monocyte surface in peripheral blood of moxifloxacin group and thymopentin group were lower than those of model group,and PD-I expression levels on T lymphocyte.B lymphocyte and monocyte surface in peripheral blood of combined treatment group were lower than those of moxifloxacin group and thymopentin group.Conclusions:Immune formulation thymopentin can enhance the anti-infective ability of multidrug-resistant Mycobacterium tuberculosis infection mice,decrease bacterial load in lung and spleen,and enhance immune function.

Ethyl pyruvate prevents inflammatory factors release and decreases intestinal permeability in rats with D-galactosamine-induced acute liver failure

BACKGROUND: The pathogenesis and progression of acute liver failure (ALF) are closely associated with intestinal endotoxemia because of the high permeability of the intestinal wall. Treatment with ethyl pyruvate (EP) has been shown to protect liver failure effectively. The current study aimed to explore the relationship between proinflammatory cytokines and intestinal permeability, and to investigate whether EP administration might prevent the release of multiple proinflammatory cytokines and decrease intestinal permeability and therefore, protect the liver from injury. METHODS: The ALF model was induced by D-galactosamine in rats. The rats were randomly divided into control (saline i.p.), model (D-galactosamine, 1.2 g/kg, i.p.), prevention [EP injection (40 mg/kg) 2 hours ahead of D-galactosamine] and treatment groups (EP injection 2 hours after D-galactosamine) Samples were obtained at 12 and 24 hours after ALF induction respectively. The histology of liver and intestinal tissue was accessed. Serum alanine aminotransferase, endotoxin, D(-) lactate, diamine oxidase (DAO), tumor necrosis factor-alpha (TNF-α), interferon-γ (IFN-γ) and high mobility group box-1 (HMGB1) were evaluated. The survival of rats was also recorded. RESULTS: The rats in model group showed severe damage to liver tissue and intestinal mucosa 12 and 24 hours after ALF induction. EP significantly improved liver or intestinal injury In addition, serum endotoxin, D(-)-lactate, DAO, TNF-α IFN-γ and HMGB1 levels were significantly increased in the model group compared with the control group. There was a positive correlation between intestinal permeability andproinflammatory cytokines. EP significantly reduced serum endotoxin, D(-)-lactate, DAO, TNF-α, IFN-γ and HMGB1 levels. The median survival time was significantly prolonged in both prevention and treatment groups (126 and 120 hours compared with 54 hours in the model group). CONCLUSIONS: EP has protective and therapeutic effects on intestinal mucosa. EP decreases intestinal permeability, and inhibits the release of multiple proinflammatory cytokines in rats with ALF.

Sodium butyrate protects against toxin-induced acute liver failure in rats

BACKGROUND: Acute liver failure(ALF) is a serious clinical syndrome with high mortality. Sodium butyrate has been shown to alleviate organ injury in a wide variety of preclinical models of critical diseases. The aim of this study was to investigate the protective effect of sodium butyrate on ALF in rats.METHODS: All rats were randomly divided into control,model and sodium butyrate treatment groups. Except the control group, the rats were induced ALF animal model by subcutaneous injection of human serum albumin+D- galactosamine+lipopolysaccharide. After induction of ALF,the rats in the treatment group received sodium butyrate(500mg/kg) at 12-hour or 24-hour time point. Fourty-eight hours after ALF induction, the animals were sacrificed and samples were harvested. Serum endotoxin, high mobility group box-1(HMGB1), liver function parameters, tumor necrosis factoralpha(TNF-α) and interferon-gamma(IFN-γ) were measured.The expression of HMGB1 and nuclear factor-kappa B(NF-κB)p65 protein in liver tissue was detected by Western blotting. The histological changes of liver and intestine were examined. The survival duration was also observed.RESULTS: Serum endotoxin, alanine aminotransferase, HMGB1,TNF-α and IFN-γ were significantly increased and the liver histology showed more severe histopathological injury in the model group compared with the control group(P<0.05).Compared to the model group, sodium butyrate treatment significantly improved the histopathological changes in the liver and intestine, reduced serum endotoxin and inflammatory cytokines, suppressed HMGB1 and NF-кB p65 proteins in liver tissue, and prolonged the survival duration regardless of treatment at 12 hours or 24 hours after induction of ALF(P<0.05).CONCLUSIONS: Sodium butyrate protected the liver from toxin-induced ALF in rats. The mechanisms may be due to direct hepatoprotection and decreased intestinal permeability.

Activating PPARy Increases NQO1 and γ-GCS Expression via Nrf2 in Thrombin-activated Microglia

The present study aimed to explore the molecular mechanisms underlying the increase of nicotinamide adenine dinucleotide phosphate:quinine oxidoreductase 1(NQO1)and y-glutamylcysteine synthetase(γ-GCS)in brain tissues after intracerebral hemorrhage(ICH).The microglial cells obtained from newborn rats were cultured and then randomly divided into the normal control group(NC group),model control group(MC group),rosiglitazone(RSG)intervention group(RSG group),retinoic-acid intervention group(RSG+RA group),and sulfbraphane group(RSG+SF group).The expression levels of NQO1,γ-GCS,and nuclear factor E2-related factor 2(Nrf2)were measured by real-time polymerase chain reaction(RT-PCR)and Western blotting,respectively.The results showed that the levels of NQO1,γ-GCS and Nrf2 were significantly increased in the MC group and the RSG group as compared with those in the NC group(P<0.01).They were found to be markedly decreased in the RSG+RA group and increased in the RSG+SF group when compared with those in the MC group or the RSG group(P<0.01).The RSG+SF group displayed the highest levels of NQO1,γ-GCS,and Nrf2 among the five groups.In conclusion,a medium dose of RSG increased the anti-oxidative ability of thrombinactivated microglia by increasing the expression of NQO1 and γ-GCS.The molecular mechanisms underlying the increase of NQO1 and γ-GCS in thrombin-activated microglia may be associated with the activation of Nrf2.

Correlation of caveolin-1 expression with microlymphatic vessel density in colorectal adenocarcinoma tissues and its correlation with prognosis

Objective: To study the expression of caveolin-1 in colorectal adenocarcinoma tissues and its correlation with microlymphatic vessel density(LMVD), and to investigate the clinical pathological prognostic significance of caveolin-1 and LMVD in patients with colorectal cancer. Methods: The expression of caveolin-1 and LMVD in 45 specimens of normal colorectal tissues, and 90 specimens of colorectal adenocarcinoma tissues were detected by immunohistochemistry technique. The correlation between their expression and the clinicopathologic features was analyzed. Muhivariable Cox regression was used to analyze the association between the laboratory indices and overall survival time. Results: The positive rates of caveolin-1 in colorectal adenocarcinoma tissues were significantly higher than those in normal colorectal tissues(P<0.01). LMVD in colorectal adenocarcinoma tissues were significantly higher than those in normal colorectal tissues(P<0.01). Mean LMVD in group with caveolin-1 positive was significantly higher than in that with caveolin-1 negative. The median survival time was 26.7 months. Cox regression analysis showed that the caveolin-1 expression, invation depth, lymph nodemetastasis, TNM stage, liver metastasis and LMVD were independent risk factors of overall survival time of patients with colorectal carcinoma. Conclusions: Caveolin-1 may contribute to the lymphangiogenesis in the tumor. During the occurrence and development of colorectal adenocarcinoma, there is a close relationship between the expression of caveolin-1 and lymphatic microvessel of tumor. Caveolin-1 expression and microlymphatic vessel density are significant prognostic value of colorectal carcinoma.

Factors affecting the production and regeneration of protoplasts: the case of the mycorrhizal fungus Tulasnella calospora from roots of orchids

Protoplast isolation is relevant for many different applications and has been principally used in proceduresnvolving genetic manipulation. In this study, the age of mycelium, osmotic stabilizers, enzyme, incubation temperature and incubation time were evaluated in terms of their effects on protoplast yield. The young mycelia （3 d） of Tulasnella calospora were digested for 6 h at 30℃ in a mixture of 1.2 mol·L-1 MgSO_4 ＋ 10 mmoI·L-1 K2HPO4 as the osmotic stabilizer, with a 1.0% lysing enzyme and 1.5% driselase： more than 106 protoplasts mL-1 were obtained. When collected 3y density gradient centrifugation, the concentration of protoplasts can reach 107-108 protoplasts mL-1, an amount suitable enough for experiments of transformation in fungi. For every 10_5 protoplasts, about 15-25 protoplasts can egenerate after 24-36 h cultivation in a liquid medium and after 8-10 d in an agar medium. This study produced an efficient method for protoplast production, reverting them into a typical mycelia morphology using a Tulasnella calospora solate.

Role of digestive protease enzymes and related genes in host plant adaptation of a polyphagous pest,Spodoptera frugiperda

The evolutionary success of phytophagous insects depends on their ability toefficiently exploit plants as a source of energy for survival.Herbivorous insects largelydepend on the efficiency,flexibility,and diversity of their digestive physiology and sophistication of their detoxification system to use chemically diverse host plants as foodsources.The fall armyworm,Spodoptera frugiperda(J.E.Smith),is a polyphagous pest ofmany commercially important crops.To elucidate the ability of this insect pest to adaptto host plant mechanisms,we evaluated the impact of primary(corn)and alternate(rice)host plants after 1l generations on gut digestive enzymatic activity and expression profiles of related genes.Results indicated that the total protease and classspecific trypsinand chymotrypsinlike protease activity of S.frugiperda significantly differed among hostplant treatments.The classspecifiq protease profiles greatly differed in S.frugiperdamidguts upon larval exposure to different treatments with inhibitors compared with treatments without inhibitors.Similarly,the single and cumulative effects of the enzymespecific inhibitors TLCK,TPCK,and E64 significantly increased larval mortality and reduced larval growth/mass across different plant treatments.Furthermore,the quantitativereverse transcription polymerase chain reaction results revealed increased transcription oftwo trypsin(SfTry3,SfTry7)and one chymotrypsin gene(Sfchym9),which indicatedthat they have roles in host plant adaptation.Knockdown of these genes resulted in significantly reduced mRNA expression levels of the trypsin genes.This was related to theincreased mortality observed in treatments compared with the dsRED control.This resultindicates possible roles of S.frugiperda gut digestive enzymes and related genes in hostplant adaptation.