Long-Term Animal Feeding Trial of the Refined Konjac Meal Ⅱ. Effects of the Refined Konjac Meal on the Aging of the Brain, Liver, and Cardiovascular Tissue Cells in Rats

Rats of both sexes were fed on a basal feed containing 1% refined konjac meal (RKM) for 18 months and the effects of RKM on the cell aging were observed. A comparable group fed on the basic feed was used as the control. Results obtained demonstrate that the long-term feeding of RKM to rats can delay the course of cell aging of the gliocyte, cadiomyocyte, and the endothelial cell of the large and medium arteriases, hence it is likely to delay the occurrence of arteriosclerosis and improve the functions of the brain, heart and vascular system.

Efficacy of Bee Products(Anzer Honey,Pollen and Propolis)in Detection and Healing of Damage Induced by Antidiabetic Drug Vildagliptin/Metformin Hydrochloride in Healthy Human Pancreatic Cells:Cytotoxic,Genotoxic and Biochemical Studies

Background and Objective Although drugs are powerful therapeutic agents,they have a range of side effects.These side effects are sometimes cellular and not clinically noticeable.Vildagliptin/metformin hydrochloride is one of the most widely used oral antidiabetic drugs with two active ingredients.In this study,we investigated its harmful effects on the metabolic activation system in healthy human pancreatic cells“hTERT-HPNE”,and we aimed to improve these harmful effects by natural products.To benefit from the healing effect,we used the unique natural products produced by the bees of the Anzer Plateau in the Eastern Black Sea Region of Turkey.Methods Cytotoxic and genotoxic effects of the drug were investigated by different tests,such as MTT,flow cytometry-apoptosis and comet assays.Anzer honey,pollen and propolis were analyzed by gas chromatography/mass spectrometry(G/C-MS).A total of 19 compounds were detected,constituting 99.9%of the samples.Results The decrease in cell viability at all drug concentrations was statistically significant compared to the negative control(P<0.05).A statistically significant decrease was detected in the apoptosis caused by vildagliptin/metformin hydrochloride with the supplementation of Anzer honey,pollen and propolis in hTERT-HPNE cells(P<0.05).Conclusion This study can contribute to other studies testing the healing properties of natural products against the side effects of oral antidiabetics in human cells.In particular,Anzer honey,pollen and propolis can be used as additional foods to maintain cell viability and improve heal damage and can be evaluated against side effects in other drug studies.

Effects of Yigan Decoction on proliferation and apoptosis of hepatic stellate cells

AIM:To investigate the effects of Chinese herb Yigan Decoction on proliferation and apoptosis of the hepatic stellate cells (HSC) in vitro. METHODS: The study in vitro was carried out in the culture of HSC lines. Various concentrations of Yigan Decoction were added and incubated. Cell proliferation was detected with MTT colorimetric assay. Cell apoptosis was detected by electron microscopy, flow cytometry and TUNEL. RESULTS: The proliferation of HSC was inhibited by Yigan Decoction, which depending on dose and time significantly. The HSC proliferation rates of groups at the end concentrations 144 and 72(g.L(-1)) were 21.62% and 40.54% respectively, significantly lower than that of normal control group(P【0.01). The HSC proliferation rates of groups at the end concentrations 36, 18 and 9(g.L(-1)) were 54.05%, 45.95% and 51.35% respectively, lower than that of control group (P【0.05). When the end concentration was 4.5 g.L(-1), the proliferation rate was 83.78%, which appeared no significant differences compared with control group. At the same concentrations of 18 g.L(-1), the inhibitory effects of Yigan Decoction at 24 h, 48 h and 72 h time point were observed, the effects were time-dependent, and reached a peak at 72 h. Meanwhile, it was showed that the inducing effects of Yigan Decoction on HSC apoptosis were dose-dependent and time-dependent. The apoptosis index(AI) was detected by TUNEL. After Yigan Decoction had been incubated for 48 h at the end concentration of 18 g.L(-1), the AI (14.5+/-3.1)% was significantly higher than that of control group (4.3+/-1.3)% (P【0.01). When visualized under transmission electron microscopy, some apoptotic stellate cells were found, i.e. dilated endoplasmic reticulum, irregular nuclei, chromatin condensation and heterochromatin ranked along inside of nuclear membrane. By flow cytometry detection, after HSC was treated with Yigan Decoction at different concentrations of 36, 18 and 9(g.L(-1)) for 48 h, AI (%) were 13.3+/-3.2, 10.7+/-2.7 and 10.1+/-2.5 respectively, which were significantly higher than that of control group(4.1+/-1.9) (P【0.01). At the same concentration of 18 g. L(-1) for 24h, 48 h and 72 h, AI (%) were 9.3+/-1.8,10.7+/-2.7 and 14.6+/-4.3 respectively, which were significantly higher than that of control group (P【0.01). CONCLUSION: Yigan Decoction could significantly inhibit HSC proliferation and increase the apoptosis index of HSC dose-dependently and time-dependently, which may be related to its mechanism of antifibrosis.

Therapeutic effect of mesenchymal stem cells from different sources in the treatment of liver diseases

Hepatitis B Virus(HBV)is still one of the important problems threatening the health and safety of human life.If the virus can not be effectively controlled,it will gradually evolve into chronic hepatitis.Chronic hepatitis will not be treated for a long time,and will gradually develop into liver fibrosis,cirrhosis,liver cancer or even liver failure and other diseases with poor prognosis.However,there is no specific western medicine treatment for liver fibrosis,cirrhosis and other liver diseases.The main treatment methods are symptomatic treatment,internal medicine comprehensive treatment and prevention of complications.In recent years,the medical technology has been continuously developed and improved,scholars at home and abroad have focused on the effective ways to prevent and treat liver diseases.More and more studies have confirmed the mesenchymal stem cells Cell(MSC)plays an important role in the treatment of liver diseases.The author will describe the therapeutic effect of MSC from different sources on liver diseases.

Late Protective Effects of the Anticalmodulin Drug Fluphenazine on Carbon Tetrachloride-induced Liver Necrosis

Fluphenazine (FP) treatment (50mg/kg bw, ip in saline) 30 min before or 6 or 10 h after CCl4 administration (1 ml/kg ip in olive oil) significantly prevented the liver necrosis produced by the hepatotoxin at 24 h. FP had enhancing effects on the covalent binding of CCl4 reactive metabolites to cellular constituents and on CCl4 induced lipid peroaldation.FP lowered bOdy temperature of the CCl4-poisoned animals during the 24 h observation period. The obtained results are compatible but do not prove the hypothesis that calmodulin (CaM) had participation in late occurring events preceding necrosis. FP lowering action on body temperature, however, might also play a role in the effects of this drug on the onset of CCl4 induced liver necrosis. FP levels in liver tissue as determined by gas chromatography-mass spectrometry evidenced the presence of the drug in amounts suffi cient to inhibit CaM and that suggests that not all preventive effects of FP are due to its indirect actions on the central nervous system via decreased body temperature

Investigating the cytotoxic effect of ibuprofen concentration in liver cancer cells(HepG2)and normal fibroblast(AGO)

Objective:Although many studies have reported that nonsteroidal anti-inflammatory drugs can have anticancer effects,the results are still challenging.The aim of this research is to Mechanism and effect of anti-inflammatory drugs in cancer treatment.Methods:In this laboratory study,cell lines were randomly divided into control group(no exposure to ibuprofen and groups exposed to ibuprofen concentrations of 10,1,0.1,and 0.001 mg/mL.The cytotoxic effect of ibuprofen was measured at 24 and 72 hours using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT).Data were compared between groups using a one-way variance test.Results:The results showed that the viability rate of HepG2 cancer cells at concentrations of 1 and 10 mg/mL decreased significantly compared to the control group in 24 hours(P<0.0001).Also,the viability rate at concentrations of 1,10,0.1,and 0.001 mg/mL decreased significantly compared to the control group in 72 h(P<0.0001).Only the concentration of 10 mg/mL ibuprofen decreased the viability of normal cells compared to the control(P<0.05).Conclusion:Overall,the results of this research showed that different concentrations of ibuprofen had a cytotoxic effect on liver cancer cells,and except for the concentration of 10 mg/mL,the other concentrations did not have a cytotoxic effect on normal cells.

Hepatic cancer stem cells and drug resistance: Relevance in targeted therapies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of most common malignancies in the world. Systemic treatments for HCC, particularly for advanced stages, are limited by the drug resistance phenomenon which ultimately leads to therapy failure. Recent studies have indicated an association between drug resistance and the existence of the cancer stem cells (CSCs) as tumor initiating cells. The CSCs are resistant to conventional chemotherapies and might be related to the mechanisms of the ATP Binding Cassette (ABC) transporters and alterations in the CSCs signaling pathways. Therefore, to contribute to the development of new HCC treatments, further information on the characterization of CSCs, the modulation of the ABC transporters expression and function and the signaling pathway involved in the self renewal, initiation and maintenance of the cancer are required. The combination of transporters modulators/inhibitors with molecular targeted therapies may be a potent strategy to block the tumoral progression. This review summarizes the association of CSCs, drug resistance, ABC transporters activities and changes in signaling pathways as a guide for future molecular therapy for HCC.

Human umbilical cord mesenchymal stem cells ameliorate liver fibrosis in vitro and in vivo: From biological characteristics to therapeutic mechanisms

Liver fibrosis is a wound-healing response to chronic injuries, characterized by the excessive accumulation of extracellular matrix or scar tissue within the liver;in addition, its formation is associated with multiple cytokines as well as several cell types and a variety of signaling pathways. When liver fibrosis is not well controlled, it can progress to liver cirrhosis, but it is reversible in principle. Thus far, no efficient therapy is available for treatment of liver fibrosis. Although liver transplantation is the preferred strategy, there are many challenges remaining in this approach, such as shortage of donor organs, immunological rejection, and surgical complications. Hence, there is a great need for an alternative therapeutic strategy. Currently, mesenchymal stem cell (MSC) therapy is considered a promising therapeutic strategy for the treatment of liver fibrosis;advantageously, the characteristics of MSCs are continuous self-renewal, proliferation, multipotent differentiation, and immunomodulatory activities. The human umbilical cord-derived (hUC)-MSCs possess not only the common attributes of MSCs but also more stable biological characteristics, relatively easy accessibility, abundant source, and no ethical issues (e.g., bone marrow being the adult source), making hUC-MSCs a good choice for treatment of liver fibrosis. In this review, we summarize the biological characteristics of hUC-MSCs and their paracrine effects, exerted by secretion of various cytokines, which ultimately promote liver repair through several signaling pathways. Additionally, we discuss the capacity of hUC-MSCs to differentiate into hepatocyte-like cells for compensating the function of existing hepatocytes, which may aid in amelioration of liver fibrosis. Finally, we discuss the current status of the research field and its future prospects.

Thinking outside the liver: Induced pluripotent stem cells for hepatic applications

The discovery of induced pluripotent stem cells (iPSCs) unraveled a mystery in stem cell research, after identification of four re-programming factors for generating pluripotent stem cells without the need of embryos. This breakthrough in generating iPSCs from somatic cells has overcome the ethical issues and immune rejection involved in the use of human embryonic stem cells. Hence, iPSCs form a great potential source for developing disease models, drug toxicity screening and cell-based therapies. These cells have the potential to differentiate into desired cell types, including hepatocytes, under in vitro as well as under in vivo conditions given the proper microenvironment. iPSC-derived hepatocytes could be useful as an unlimited source, which can be utilized in disease modeling, drug toxicity testing and producing autologous cell therapies that would avoid immune rejection and enable correction of gene defects prior to cell transplantation. In this review, we discuss the induction methods, role of reprogramming factors, and characterization of iPSCs, along with hepatocyte differentiation from iPSCs and potential applications. Further, we discuss the location and detection of liver stem cells and their role in liver regeneration. Although tumor formation and genetic mutations are a cause of concern, iPSCs still form a promising source for clinical applications.

Non-steroidal anti-inflammatory drugs:What is the actual risk of liver damage?

Non-steroidal anti-inflammatory drugs (NSAIDs) constitute a family of drugs, which taken as a group, represents one of the most frequently prescribed around the world. Thus, not surprisingly NSAIDs, along with antiinfectious agents, list on the top for causes of DrugInduced Liver Injury (DILI). The incidence of liver disease induced by NSAIDs reported in clinical studies is fairly uniform ranging from 0.29/100 000 [95% confidence interval (CI): 0.17-051] to 9/100 000 (95% CI: 6-15). However, compared with these results, a higher risk of liver-related hospitalizations was reported (3-23 per 100 000 patients). NSAIDs exhibit a broad spectrum of liver damage ranging from asymptomatic, transient, hyper-transaminasemia to fulminant hepatic failure. However, under-reporting of asymptomatic, mild cases, as well as of those with transient liver-tests alteration, in conjunction with reports non-compliant with pharmacovigilance criteria to ascertain DILI and flawed epidemiological studies, jeopardize the chance to ascertain the actual risk of NSAIDs hepatotoxicity. Several NSAIDs, namely bromfenac, ibufenac and benoxaprofen, have been withdrawn from the market due to hepatotoxicity; others like nimesulide were never marketed in some countries and withdrawn in others. Indeed, the contro-versy concerning the actual risk of severe liver disease persists within NSAIDs research. The present work intends (1) to provide a critical analysis of the dissimilar results currently available in the literature concerning the epidemiology of NSAIDS hepatotoxicity; and (2) to review the risk of hepatotoxicity for each one of the most commonly employed compounds of the NSAIDs family, based on past and recently published data.

Glutamine:aprecursor of glutathione and its effect on liver

AIM To investigate the relationship between alanyl-glutamine (ALA-GLN) and glutathione (GSH) biosynthesis in hepatic protection.METHODS Twenty male Wistar rats were randomly divided into two groups: one receiving standard parenteral nutrition (STD) and the other supplemented with or without ALA-GLN for 7 days. The blood and liver tissue samples were examined after 5-fluorouracil (5-FU) was injected peritoneally.RESULTS The concentration measurements were significantly higher in ALA-GLN group than in STD group in serum GLN (687 μmol/ L±50 μmol/ L vs 505 μmol/ L±39 μmol/ L, P＜0.05), serum GSH (14 μmol/ L±5 μmol/ L vs 7 μmol/ L±3 μmol/ L, P＜0.01) and in liver GSH content (6.9 μmol/ g±2.5 μmol/ g vs 4.4 μmol/ g±1.6 μmol/ g liver tissue, P＜0.05). Rats in ALA-GLN group had lesser elevations in hepatic enzymes after 5-FU administration.CONCLUSION The supplemented nutrition ALA-GLN can protect the liver function through increasing the glutathione biosynthesis and preserving the glutathione stores in hepatic tissue.

Biochemical mechanisms in drug-induced liver injury:Certainties and doubts

Drug-induced liver injury is a significant and still unresolved clinical problem. Limitations to knowledge about the mechanisms of toxicity render incomplete the detection of hepatotoxic potential during preclinical development. Several xenobiotics are lipophilic substances and their transformation into hydrophilic compounds by the cytochrome P-450 system results in production of toxic metabolites. Aging, preexisting liver disease, enzyme induction or inhibition, genetic variances, local 02 supply and, above all, the intrinsic molecular properties of the drug may affect this process. Necrotic death follows antioxidant consumption and oxidation of intracellular proteins, which determine increased permeability of mitochondrial membranes, loss of potential, decreased ATP synthesis, inhibition of Ca^2＋-dependent ATPase, reduced capability to sequester Ca^2＋ within mitochondria, and membrane bleb formation. Conversely, activation of nucleases and energetic participation of mitochondria are the main intracellular mechanisms that lead to apoptosis. Non-parenchymal hepatic cells are inducers of hepatocellular injury and targets for damage. Activation of the immune system promotes idiosyncratic reactions that result in hepatic necrosis or cholestasis, in which different HLA genotypes might play a major role. This review focuses on current knowledge of the mechanisms of drug-induced liver injury and recent advances on newly discovered mechanisms of liver damage. Future perspectives including new frontiers for research are discussed.

Signal transducer and activator of transcription 3 promotes the Warburg effect possibly by inducing pyruvate kinase M2 phosphorylation in liver precancerous lesions

BACKGROUND Study shows that signal transducer and activator of transcription 3(STAT3) can increase the Warburg effect by stimulating hexokinase 2 in breast cancer and upregulate lactate dehydrogenase A and pyruvate dehydrogenase kinase 1 in myeloma. STAT3 and pyruvate kinase M2(PKM2) can also be activated and enhance the Warburg effect in hepatocellular carcinoma. Precancerous lesions are critical to human and rodent hepatocarcinogenesis. However, the underlying molecular mechanism for the development of liver precancerous lesions remains unknown. We hypothesized that STAT3 promotes the Warburg effect possibly by upregulating p-PKM2 in liver precancerous lesions in rats.AIM To investigate the mechanism of the Warburg effect in liver precancerous lesions in rats.METHODS A model of liver precancerous lesions was established by a modified Solt-Farber method. The liver pathological changes were observed by HE staining and immunohistochemistry. The transformation of WB-F344 cells induced with Nmethyl-N'-nitro-N-nitrosoguanidine and hydrogen peroxide was evaluated by the soft agar assay and aneuploidy. The levels of glucose and lactate in the tissue and culture medium were detected with a spectrophotometer. The protein levels of glutathione S-transferase-π, proliferating cell nuclear antigen(PCNA), STAT3,and PKM2 were examined by Western blot and immunofluorescence.RESULTS We found that the Warburg effect was increased in liver precancerous lesions in rats. PKM2 and p-STAT3 were upregulated in activated oval cells in liverprecancerous lesions in rats. The Warburg effect, p-PKM2, and p-STAT3 expression were also increased in transformed WB-F344 cells. STAT3 activation promoted the clonal formation rate, aneuploidy, alpha-fetoprotein expression,PCNA expression, G1/S phase transition, the Warburg effect, PKM2 phosphorylation, and nuclear translocation in transformed WB-F344 cells.Moreover, the Warburg effect was inhibited by stattic, a specific inhibitor of STAT3, and further reduced in transformed WB-F344 cells after the intervention for PKM2.CONCLUSION The Warburg effect is initiated in liver precancerous lesions in rats. STAT3 activation promotes the Warburg effect by enhancing the phosphorylation of PKM2 in transformed WB-F344 cells.

Experimental study on antitumor effect of arsenic trioxide in combination with cisplatin or doxorubicin on hepatocellular carcinoma

INTRODUCTIONThe main component of a traditional Chinese drug 'Pishuang'. arsenic trioxide (As2O3), has obviously selective anti-tumor effect on human hepatocellular carcinoma (HCC)in both in vitro and in vivo studies[1-5]. Due to limited effectiveness when any anti-carcinogen is used alone and obviously increased toxicity when the dose is raised, there is no exception for As2O3. Furthermore, combined chemotherapy contributes to improve therapeutic effectiveness, disperse toxicity and surmount drug-resistance,in which the combination of traditional Chinese and modern medicine has more advantages and characteristics. As a result,we made an experimental study on anti-tumor effect of As2O3in combination with cisplantin (PDD) or doxorubicin (ADM)on HCC. to investigate the possibility of AS2O3 in combination with PDD or ADM and nature of interaction between them,and to provide experimental basis for clinical application.

Effects of aminoguanidine on nitric oxide production induced by inflammatory cytokines and endotoxin in cultured rat hepatocytes

AIM: To study the effects of aminoguanidine (AG) and two L-arginine analogues N(omega)-nitro-L-arginine methyl ester (L-NAME) and N(omega)-nitro-L-arginine (L-NNA) on nitric oxide (NO) production induced by cytokines (TNF-alpha, IL-1 beta, and IFN-gamma) and bacterial lipopolysaccharide (LPS) mixture (CM) in the cultured rat hepatocytes, and examine their mechanisms action. METHODS: Rat hepatocytes were incubated with AG, L-NAME, L-NNA, Actinomycin D (ActD) and dexamethasone in a medium containing CM (LPS plus TNF-alpha, IL-1 beta, and IFN-gamma) for 24h. NO production in the cultured supernatant was measured with the Griess reaction. Intracellular cGMP level was detected with radioimmunoassy. RESULTS: NO production was markedly blocked by AG and L-NAME in a dose-dependent manner under inflammatory stimuli condition triggered by CM in vitro. The rate of the maximum inhibitory effects of L-NAME (38.9%) was less potent than that obtained with AG(53.7%, P 【 0.05). There was no significant difference between the inhibitory effects of AG and two L-arginine analogues on intracellular cGMP accumulation in rat cultured hepatocytes. Non-specific NOS expression inhibitor dexamethasone (DEX)and iNOS mRNA transcriptional inhibitor ActD also significantly inhibited CM-induced NO production. AG(0.1 mmol x L(-1)) and ActD (0.2 ng x L(-1)) were equipotent in decreasing NO production induced by inflammatory stimuli in vitro, and both effects were more potent than that induced by non-selectivity NOS activity inhibitor L-NAME (0.1 mmol x L(-1)) under similar stimuli conditions (P【0.01). CONCLUSION: AG is a potent selective inhibitor of inducible isoform of NOS,and the mechanism of action may be not only competitive inhibition in the substrate level, but also the gene expression level in rat hepatocytes.

Dissecting the molecular pathophysiology of drug-induced liver injury

Drug-induced liver injury(DILI) has become a major topic in the field of Hepatology and Gastroenterology. DILI can be clinically divided into three phenotypes: hepatocytic, cholestatic and mixed. Although the clinical manifestations of DILI are variable and the pathogenesis complicated, recent insights using improved preclinical models, have allowed a better understanding of the mechanisms that trigger liver damage. In this review, we will discuss the pathophysiological mechanisms underlying DILI. The toxicity of the drug eventually induces hepatocellular damage through multiple molecular pathways, including direct hepatic toxicity and innate and adaptive immune responses. Drugs or their metabolites, such as the common analgesic, acetaminophen, can cause direct hepatic toxicity through accumulation of reactive oxygen species and mitochondrial dysfunction. The innate and adaptive immune responses play also a very important role in the occurrence of idiosyncratic DILI. Furthermore, we examine common forms of hepatocyte death and their association with the activation of specific signaling pathways.

Liver injury associated with drug intake during pregnancy

Drug use during pregnancy is not common.Drug-induced liver injury(DILI)is a potential complication that is rare but can adversely affect both the mother and the fetus.Although many drugs can directly cause hepatotoxicity,idiosyncratic liver injury is common in pregnancy.Underreporting of adverse drug reactions,lack of adequate literature regarding drug safety in pregnancy,and the inherent difficulty in diagnosing DILI during pregnancy make the management of this condition challenging.This review attempts to describe the existing literature regarding DILI in pregnancy,which is mainly in the form of case reports;several studies have looked at the safety of antithyroid drugs,antiretroviral drugs,and paracetamol,which have an indication for use in pregnancy;the relevant data from these studies with regard to DILI has been presented.In addition,the review describes the diagnosis of DILI,grading the disease severity,assessment of causality linking the drug to the adverse event,regulatory guidelines for evaluating the potential of drugs to cause liver injury,efforts to ensure better participation of women in clinical trials and studies in pregnant women population in particular,and the challenges involved in generating adequate research evidence.The establishment of DILI registries in various countries is an encouraging development;however,there is a need for promoting active,spontaneous reporting of adverse events during pregnancy to ensure rapid generation of evidence regarding the safety of a drug in pregnant women.

Adeno-associated virus mediated endostatin gene therapy in combination with topoisomerase inhibitor effectively controls liver tumor in mouse model

AIM:rAAV mediated endostatin gene therapy has been examined as a new method for treating cancer.However, a sustained and high protein delivery is required to achieve the desired therapeutic effects.We evaluated the impact of topoisomerase inhibitors in rAAV delivered endostatin gene therapy in a liver tumor model. METHODS:rAAV containing endostatin expression cassettes were transduced into hepatoma cell lines.To test whether the topoisomerase inhibitor pretreatment increased the expression of endostatin,Western blotting and ELISA were performed.The biologic activity of endostatin was confirmed by endothelial cell proliferation and tube formation assays. The anti-tumor effects of the rAAV-endostatin vector combined with a topoisomerase inhibitor,etoposide,were evaluated in a mouse liver tumor model. RESULTS:Topoisomerase inhibitors,including camptothecin and etoposide,were found to increase the endostatin exPression level in vitro.The over-expressed endostatin, as a result of pretreatment with a topoisomerase inhibitor, was also biologically active.In animal experiments,the combined therapy of topoisomerase inhibitor,etoposide with the rAAV-endostatin vector had the best tumor- suppressive effect and tumor foci were barely observed in livers of the treated mice.Pretreatment with an etoposide increased the level of endostatin in the liver and serum of rAAV-endostatin treated mice.Finally,the mice treated With rAAV-endostatin in combination with etoposide showed the longest survival among the experimental models. CONCLUSION:rAAV delivered endostatin gene therapy in combination with a topoisomerase inhibitor pretreatment is an effective modality for anticancer gene therapy.

CD4+Foxp3+CD25+/-Tregs characterize liver tissue specimens of patients suffering from drug-induced autoimmune hepatitis:A clinical-pathological study

Background: The diagnosis of drug-induced autoimmune hepatitis(DIAIH) and its differentiation from idiopathic autoimmune hepatitis(AIH) is challenging. This study aimed to differentiate DIAIH from AIH by comparing the biochemical changes, histological features, and frequencies of CD4~+Foxp3~+CD25+/-regulatory T cells(Tregs) in liver tissues or peripheral blood lymphocytes.Methods: A total of 15 DIAIH patients and 24 AIH patients who underwent liver biopsies at initial presentation were enrolled in this study. The liver histological changes were assessed by HE staining. The phenotypic recognition and distribution of CD4~+Foxp3~+CD25+/-Tregs in liver tissues were evaluated by single/double immunostains in serial sections. The CD4~+Foxp3~+CD25+/-Tregs in peripheral blood were analyzed by flow cytometry.Results: The median values of ALT and AST were 404.50 U/L and 454.10 U/L in DIAIH patients and309.50 U/L and 315.00 U/L in AIH patients, respectively. More importantly, for the first time we found that patients with DIAIH had higher levels of serum ALT and AST, more severe degree of lobular inflammation,higher frequencies of zone 3 necrosis and higher number of lobular CD4~+Foxp3~+CD25~-Tregs compared with AIH(P < 0.05). Furthermore, there were positive correlations in DIAIH between the degree of lobular inflammation and either the AST/ALT level or the number of lobular CD4~+Foxp3~+CD25~-Tregs(P < 0.05).However, the frequency of peripheral blood CD4~+Foxp3~+CD25+/-Tregs were not significantly different between DIAIH and AIH.Conclusions: The differences of ALT, AST and the number of lobular CD4~+Foxp3~+CD25~-Tregs between patients with DIAIH and those with AIH are clinically helpful in differentiating these two diseases in their early stage.

Effects of combined use of diallyl disulfide and N-acetyl-cysteine on acetaminophen hepatotoxicity in β-naphthoflavone-pretreated mice

AIMS To assess the protective effect of diallyl disulfide (DADS) and its combined use with N-acetyl-cysteine (NAC) on acetaminophen (APAP) hepatotoxicity in C57BL/6N (B6) mice pretreated with β naphthoflavone (BNF). METHODS B6 mice were divided into six groups and all compounds used were injected intraperitoneally. Except for control and APAP group (receiving APAP only), the other groups received an injection of APAP (350mg/kg) 48 hours after BNF (200mg/kg) and either of DADS (200mg/kg), or NAC (500mg/kg) or both DADS and NAC. DADS was given 2 hours before APAP and NAC was injected with APAP. The mean survival time was recorded and livers were examined histologically. Hepatic glutathione (GSH) levels and plasma ALT were also determined at different time points. To evaluate the effect of DADS or NAC on hepatic P450 induction by BNF, liver microsomes were prepared and 7 ethoxyresorufin O dealkylase (ERD) activity was determined using spectrofluorometrical methods. In vitro effect of DADS or NAC on ERD activity was assayed by directly incubating microsomal suspension with DADS or NAC of different concentrations. RESULTS APAP was not toxic to mice without BNF pretreatment, but caused severe liver necrosis and death of all BNF treated mice in 4 hours. A sharp depletion of GSH (approximately 62% of its initial content at 2 hours and 67% at 4 hours) and a linear elevation of ALT levels (536 8±29 5 Sigma units at 2 hours and 1302 5±74 9 at 4 hours) were observed. DADS and NAC given individually produced mild protection, resulting in prolonged survival, a slower decline of GSH level and a less steeper elevation of ALT level. All mice died eventually. Co administration of DADS and NAC completely protected mice. GSH level in this group lowered by about 35% and 30% at 2 and 4 hours, and ALT was 126±18 and 157 5±36 6 Sigma units at 2 and 4 hours. ERD activity in BNF treated mice was about 5 times that of the constitutive level determined in normal mice. Neither DADS nor NAC inhibited P450 1A1/1A2 induction as determined by their effect on the induction of ERD activity. In vitro assay indicates that DADS, but not NAC, was a potent inhibitor of ERD activity (IC 50 =4 6μM). CONCLUSIONS A combined use of both DADS and NAC produced full protection in BNF treated mice against APAP hepatotoxicity. The mechanism is that DADS inhibits P450 1A1/1A2 activity, but not induction, which substantially reduces production of NAPQI, while NAC enhances liver detoxifying capability via serving as a precursor of GSH and stimulating GSH synthesis.