Ameliorated Liver Damage Research Articles

Beneficial effects of mineralocorticoid receptor blockade in experimental non-alcoholic steatohepatitis.

Therapeutic options to treat Non-alcoholic steatohepatitis (NASH) are limited. Mineralocorticoid receptor (MR) activation could play a role in hepatic fibrogenesis and its modulation could be beneficial for NASH. To investigate whether eplerenone, a specific MR antagonist, ameliorates liver damage in experimental NASH. C57bl6 mice were fed a choline-deficient and amino acid-defined (CDAA) diet for 22 weeks with or without eplerenone supplementation. Serum levels of aminotransferases and aldosterone were measured and hepatic steatosis, inflammation and fibrosis scored histologically. Hepatic triglyceride content (HTC) and hepatic mRNA levels of pro-inflammatory pro-fibrotic, oxidative stress-associated genes and of MR were also assessed. CDAA diet effectively induced fibrotic NASH, and increased the hepatic expression of pro-inflammatory, pro-fibrotic and oxidative stress-associated genes. Hepatic MR mRNA levels significantly correlated with the expression of pro-inflammatory and pro-fibrotic genes and were significantly increased in hepatic stellate cells obtained from CDAA-fed animals. Eplerenone administration was associated to a reduction in histological steatosis and attenuation of liver fibrosis development, which was associated to a significant decrease in the expression of collagen-α1, collagen type III, alpha 1 and Matrix metalloproteinase-2. The expression of MR correlates with inflammation and fibrosis development in experimental NASH. Specific MR blockade with eplerenone has hepatic anti-steatotic and anti-fibrotic effects. These data identify eplerenone as a potential novel therapy for NASH. Considering its safety and FDA-approved status, human studies are warranted.

Effects of dietary supplementation with palygorskite on nutrient utilization in weaned piglets

The objective of this study was to investigate the effects of dietary palygorskite supplementation on nutrient utilization in weaned piglets. Twenty-seven weaned piglets (age, 24 days; weight, 7.32±0.12kg) were allocated to three treatment groups (n=9 each) and each pig was considered to be a replicate. The control group was fed a basal diet and the two palygorskite treatments groups were fed a basal diet supplemented with either 2000 or 3000mg/kg palygorskite for 42 days. On days 21 and 42, blood samples were collected for measurement of serum biochemical parameters, and three piglets from each group were sacrificed to collect intestinal digesta to assess the activities of gastrointestinal tract digestive enzymes. Titanium dioxide was added to all diets at 0.3% and used as a marker to determine nutrient digestibility at the end of the trial. The feed/gain and diarrhea index were decreased in the 2000mg/kg palygorskite group (P<0.05), as compared with controls, between days 1 and 21. Aspartate aminotransferase activity and serum triglyceride concentration of the two palygorskite groups were lower than those of the control group on day 21 (P<0.05). Digestibility of dry matter and gross energy in the 2000mg/kg palygorskite group were higher than those of the control group (P<0.05). Compared with the 2000mg/kg palygorskite group, digestibility of dry matter was reduced in the 3000mg/kg group (P<0.05). Crude fat digestibility was decreased in both palygorskite-treatment groups and a significant difference was observed between the 3000mg/kg palygorskite group and control group (P<0.05). The results showed that dietary supplementation with palygorskite improved growth performance, ameliorated liver damage, increased dry matter, energy and crude protein utilization, while a lower dose (2000mg/kg) seemed to be more effective than a higher dose (3000mg/kg) to decrease crude fat digestibility in weaned piglets.

Ameliorative Role and Antioxidant Effect of Propolis against Hepatotoxicity of Fenvalerate in Albino Rats

The present work studied the effect of Pyrethroid Insecticidefenvalerate on albino rats' liver and possible ameliorative roles played by Propolis. In this study the Fenvalerate treatment has confirmed to induce many histological changes in the liver of albino rats including congestion of blood vessels, cytoplasmic vacuolization of the hepatocytes, necrosis and fatty degeneration. Biochemical results showed that fenvalerate caused marked elevation in serum ALT and AST. It also caused an increase in malondialdehyde and depletion in activity of the antioxidant enzymes, catalase and superoxide dismutase in the liver organ. Treating animals with fenvalerate and Propolis led to an improvement in both histological and biochemical alterations induced by fenvalerate. Moreover, Propolis was found to reduced the level of malondialdehyde and increased the activity level of antioxidant enzymes, SOD and CAT. These results indicated that Propolis ameliorated liver damage induced by fenvalerate and this could attribute to Propolis antioxidant activity and free radicals scavenging properties.

Recombinant Trichinella spiralis-53000 protein alleviates liver damage due to lipopolysaccharides via M2 macrophage activation

To evaluate if recombinant Trichinella spiralis-53 000 protein (rTsP53) could alleviate liver damage caused by lipopolysaccharides (LPS) via M2 macrophage activation. Sixty male BALB/c mice were randomly divided into LPS group, LPS + phosphate buffer saline (PBS) group and rTsP53 intervention group by random number table, with 20 mice in each group. Intraperitoneal injection of 15 μg/kg LPS was performed for all the mice in the three groups after 8 hours of fasting. The mice in LPS + PBS group were injected with PBS after 1 hour of LPS injection. The mice in the rTsP53 intervention group were injected with rTsP53 (5 mg/kg) after 1 hour of LPS injection. After 48 hours all the mice were sacrificed. Peritoneal macrophages were harvested and flow cytometry (FCM) was used to detect markers CCR7 (M1) and CD206 (M2) of macrophages. Hepatic tissue was harvested for pathological study after hematoxylin-eosin (HE) staining, and double staining immunofluorescence was used to detect F4/80⁺ HLA-DR⁺ and F4/80⁺ CD163⁺. Peripheral blood serum was harvested to detect the levels of aspartate transaminase (AST) and alanine transaminase (ALT). Compared with LPS and LPS + PBS groups, survival rate of mice of rTsP53 intervention group was significantly elevated (90% vs. 25%, 30%, both P<0.01), and the pathological injury of the liver was significantly ameliorated, and the hepatic structure was better preserved. The transaminase in rTsP53 intervention group was significantly lower than that of LPS and LPS + PBS groups (ALT: 97.7 ± 8.5 U/L vs. 181.7 ± 19.5 U/L, 173.7 ± 17.2 U/L; AST: 142.7 ± 12.1 U/L vs. 235.7 ± 9.9 U/L, 213.7 ± 6.7 U/L, all P<0.05), FITC-CD206⁺ proportion of peritoneal macrophage was significantly higher [(17.75 ± 0.30)% vs. (1.38 ± 0.13)%, (1.36 ± 0.05)%, both P<0.05] while PE-CCR7(+) proportion [(6.89 ± 0.11)% vs. (15.30 ± 0.64)%, (14.96 ± 0.93)%, both P<0.05] was significantly lower. Fluorescence intensity of macrophages with F4/80⁺ CD163⁺ double staining for liver sections was significantly increased (0.36 ± 0.01 vs. 0.29 ± 0.02, 0.31 ± 0.01, both P<0.05), while there was no significant difference in the fluorescence intensity of macrophages with F4/80⁺ HLA-DR⁺ double staining (0.30 ± 0.01 vs. 0.30 ± 0.02, 0.31 ±0.01, both P>0.05). There was no significant difference of above results between LPS group and LPS + PBS group (all P>0.05). rTsP53 could ameliorate liver damage caused by LPS and improve animal's survival via the activation of M2 macrophage.

L-carnitine prevents progression of non-alcoholic steatohepatitis in a mouse model with upregulation of mitochondrial pathway.

Non-alcoholic steatohepatitis (NASH) is a severe form of non-alcoholic fatty liver disease characterized by lobular inflammation, hepatocellular ballooning, and fibrosis with an inherent risk for progression to cirrhosis and hepatocellular carcinoma (HCC). Mitochondrial dysfunction appears to play a role in the progression from simple steatosis to NASH. L-carnitine (L-b-hydroxy-g-N-trimethylaminobutyric acid), an essential nutrient that converts fat into energy in mitochondria, has been shown to ameliorate liver damage. The aim of the present study was to explore the preventive and therapeutic effect of L-carnitine in NASH model mice. Eight-week-old male STAM mice, a NASH-cirrhosis-hepatocarcinogenic model, were divided into 3 experimental groups and fed as follows: 1) high-fat diet (HFD) (control group); 2) HFD mixed with 0.28% L-carnitine (L-carnitine group); and 3) HFD mixed with 0.01% α-tocopherol (α-tocopherol group). After 4 or 8 weeks, mice were sacrificed. Blood samples and livers were collected, and hepatic tumors were counted and measured. Livers were subjected to histological study, immunohistochemical staining of 4-hydroxynonenal and ferritin, determination of 8-OHdG levels, mRNA and protein expressions for multiple genes, and metabolomic analysis. The intestinal microbiome was also analyzed. L-carnitine increased hepatic expression of genes related to long-chain fatty acid transport, mitochondrial β-oxidation, and antioxidant enzymes following suppression of hepatic oxidative stress markers and inflammatory cytokines in NASH, and mice treated with L-carnitine developed fewer liver tumors. Although α-tocopherol resulted in NASH improvement in the same manner as L-carnitine, it increased periodontitis-related microbiotic changes and hepatic iron transport-related gene expression and led to less effective for anti-hepatocarcinogenesis.ConclusionL-carnitine prevents progression of non-alcoholic steatohepatitis in a mouse model by upregulating the mitochondrial β-oxidation and redox system.

Hepatoprotective bioactivity of the glycoprotein, antrodan, isolated from Antrodia cinnamomea mycelia.

Antrodan, a protein-bound polysaccharide isolated from Antrodia cinnamomea mycelia, was demonstrated to exhibit significant anti-inflammatory bioactivity in vitro. However, its role in hepatic injury in vivo still remains unclear. We hypothesized that antrodan may have beneficial hepatoprotective effects. To verify this, a lipopolysaccharide (LPS)-Sprague-Dawley rat model was used. Antrodan protected against liver damage by suppressing LPS-stimulated serum glutamine-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), interleukin (IL)-6, hepatic thiobarbituric acid reactive substances (TBARS), nitric oxide (NO), inducible NO synthase (iNOS) and nuclear factor (NF)-κB, and by effectively alleviating the downregulated hepatic superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH-Px). Hematoxylin-eosin staining revealed that antrodan at a dosage of 40 mg/kg was able to alleviate LPS-induced liver damage to a normal status. In addition, we identified the partial main architectural backbone of antrodan to have a 1→3 linear β-glycosidic backbone of mannan linked by β-1→3 glucosidic branches. Conclusively, antrodan can potentially ameliorate liver damage in vivo by suppressing oxidative stress induced by LPS.

Potential Approaches to Ameliorate Hepatic Fat Accumulation Seen with MTP Inhibition

Microsomal triglyceride transfer protein (MTP) is one of the promising targets for the therapy of dyslipidemia and MTP inhibition can lead to robust plasma low-density lipoprotein cholesterol (LDL-C) reduction. Lomitapide, a small-molecule MTP inhibitor, was recently approved by the US FDA as an additional treatment for homozygous familial hypercholesterolemia (hoFH). However, liver-related side effects, including hepatic fat accumulation and transaminase elevations, are the main safety concerns associated with MTP inhibitors. Here, we review recent knowledge on the mechanisms underlying liver toxicity of MTP inhibitors. The contribution of altered levels of intracellular triglycerides, cholesteryl esters, and free cholesterols toward cellular dysfunction is specifically addressed. On this basis, therapies targeted to attenuate cellular lipid accumulation, to reduce risk factors for non-alcoholic fatty liver disease (NAFLD) (i.e., insulin resistance and oxidative stress) and to specifically inhibit intestinal MTP may be useful for ameliorating liver damage induced by MTP inhibitors. In particular, weight loss through lifestyle interventions is expected to be the most effective and safest way to minimize the undesirable side effects. Specific dietary supplementation might also have protective effects against hepatosteatosis. Despite that, to date, few clinical data support these therapeutic options in MTP inhibition-related liver damage, such proposed approaches may be further explored in the future for their use in preventing unwanted effects of MTP inhibitors.

Ginsenoside Rg1 attenuates concanavalin A-induced hepatitis in mice through inhibition of cytokine secretion and lymphocyte infiltration

The effect of ginsenoside Rg1 (Rg1) on hepatic damage caused by concanavalin A (Con A) has not been fully elucidated. This study was designed to evaluate the protective effect of Rg1 on Con A-induced hepatitis in mice and explore the potential mechanisms of this effect. C57BL/6 mice were divided randomly into the following four experimental groups: phosphate-buffered saline group, Rg1 group, Con A group, Con A + Rg1 group. Mice received Rg1 (20 mg/kg) 3 h before intravenous administration of Con A (15 mg/kg). Levels of alanine transaminase, aspartate transaminase and cytokine production were measured, the amount of phosphorylated IκBα and p65 were tested, the numbers of CD4(+) and CD8(+) T lymphocytes infiltrated in the blood, spleen and liver were calculated, intercellular adhesion molecule-1 (ICAM-1) and interferon-inducible chemokine-10 (CXCL-10) levels were measured and histological examination of the livers was conducted. Pretreatment with Rg1 markedly reduced the elevated levels of serum aminotransferase, ameliorated liver damage and suppressed proinflammatory cytokines secretion via inhibition NF-κB activity following Con A injection of mice. Furthermore, Rg1 administration reduced ICAM-1 and CXCL-10 mRNA expression in the liver as well as the number of CD4(+) and CD8(+) T lymphocytes infiltrating in the liver. Rg1 reduced the incidence of liver damage through inhibition of the proinflammatory response and suppressed the recruitment of CD4(+) and CD8(+) T lymphocytes to the liver. These data indicate that Rg1 represents a novel agent for the treatment of T lymphocyte-dependent liver injury.

Targeting TIM-1 on CD4 T Cells Depresses Macrophage Activation and Overcomes Ischemia-Reperfusion Injury in Mouse Orthotopic Liver Transplantation

Hepatic injury due to cold storage followed by reperfusion remains a major cause of morbidity and mortality after orthotopic liver transplantation (OLT). CD4 T cell TIM-1 signaling costimulates a variety of immune responses in allograft recipients. This study analyzes mechanisms by which TIM-1 affects liver ischemia-reperfusion injury (IRI) in a murine model of prolonged cold storage followed by OLT. Livers from C57BL/6 mice, preserved at 4°C in the UW solution for 20 h, were transplanted to syngeneic recipients. There was an early (1 h) increased accumulation of TIM-1+ activated CD4 T cells in the ischemic OLTs. Disruption of TIM-1 signaling with a blocking mAb (RMT1-10) ameliorated liver damage, evidenced by reduced sALT levels and well-preserved architecture. Unlike in controls, TIM-1 blockade diminished OLT expression of Tbet/IFN-γ, but amplified IL-4/IL-10/IL-22; abolished neutrophil and macrophage infiltration/activation and inhibited NF-κB while enhancing Bcl-2/Bcl-xl. Although adoptive transfer of CD4 T cells triggered liver damage in otherwise IR-resistant RAG(-/-) mice, adjunctive TIM-1 blockade reduced Tbet transcription and abolished macrophage activation, restoring homeostasis in IR-stressed livers. Further, transfer of TIM-1(Hi) CD4+, but not TIM-1(Lo) CD4+ T cells, recreated liver IRI in RAG(-/-) mice. Thus, TIM-1 expressing CD4 T cells are required in the mechanism of innate immune-mediated hepatic IRI in OLTs.

Effects of transplanted bone-marrow-derived mesenchymal stem cells in animal models of acute hepatitis

Our aim was to evaluate the therapeutic effects of bone-marrow-derived mesenchymal stem cells (BMMSCs) on ConA-induced hepatitis and to elucidate the possible mechanism involved. MSCs were isolated from bone marrow and their characteristics and anti-apoptotic effects on the L02 cell line were analyzed. The effect of intravenous infusion of BMMSCs on liver damage was also tested. Furthermore, the recruitment of donor BMMSCs to the liver of recipient animals and their effects on the activity of intrahepatic natural killer T (NKT) cells were investigated. BMMSCs ameliorated liver damage in a time- and dose-dependent manner. Donor BMMSCs were detected in the livers of recipient animals, suggesting that tissue damage stimulated the migration of BMMSCs. Transplanted BMMSCs also suppressed the activity of intrahepatic NKT cells, not only in the liver but throughout the body. The general infusion of BMMSCS ameliorated immunoregulatory activities by the suppression of intrahepatic NKT cells.

Glycine ameliorates liver injury and vitamin D deficiency induced by bile duct ligation

BackgroundPatients with chronic liver disease had lower serum concentrations 25-hydroxyvitamin D (25OHD). Glycine, a nonessential amino acid, exerts anti-inflammatory, cytoprotective, and immunomodulatory properties. This study aimed to establish a tandem mass spectrometry assay to measure 25OHD in guinea pigs serum and to investigate the effects of glycine against the liver damage induced by bile duct ligation (BDL). MethodsBDL was performed on male guinea pigs. Glycine, alanine, serine or tyrosine was given by intraperitoneal injection. The animals were sacrificed and examined at 7 and 14days after BDL. Serum concentrations of total bilirubin and aminotransferase were measured. Serum concentrations of 25OHD2 and 25OHD3 were measured by API 5000 mass spectrometer. In addition, oxidative stress was assessed by serum ischemia-modified albumin (IMA) and hepatic malondialdehyde (MDA), and apoptosis by hepatic caspase 3 activities. ResultsSerum 25OHD concentrations were decreased around 50% in the BDL group at days 7 and 14 post ligation, compared to sham (mean 65.3ng/ml, p<0.005). Glycine but not other amino acid treatment blunted the reduced serum 25OHD (52.6ng/ml, p<0.05) resulting from BDL. The concentrations of 25OHD were negatively associated with concentrations of IMA (r=−0.305, p<0.05) and caspase 3 (r=−0.562, p<0.0001). At day-14 post ligation, glycine treatment also ameliorated liver damage indicated by serum AST (p<0.005), ALT (p<0.05) and hepatic caspase 3 activities (p<0.05) and oxidative stress. ConclusionOur results indicate that glycine may protect against BDL-induced liver injury through attenuation of oxidative stress, apoptosis and the vitamin D deficiency.

Protective effect of fucoidan against acetaminophen-induced liver injury

Fucoidan, a sulfated polysaccharide extracted from various brown seaweeds, possesses a wide range of pharmacological properties. In this study, we investigated the protective effect of fucoidan on acetaminophen-induced acute liver injury in rats. Liver injury was induced by administration of acetaminophen (800 mg/kg, i.p.) and fucoidan was administered (100 mg kg, p.o.) 2 h before and after acetaminophen administration. After 24 h, co-treatment of fucoidan ameliorated liver damage and cell death induced by acetaminophen. Acetaminophen induced the overexpression of CYP2E1, one of the metabolizing enzymes of acetaminophen, but cotreatment with fucoidan suppressed its increased expression of CYP2E1. Fucoidan also reduced the hepatic apoptosis induced by acetaminophen exposure as shown in the protein expression of Bax, Bcl-2, and cleaved caspase-3. The anti-oxidative effect of fucoidan was observed from the increase of the production and expression of glutathione, superoxide dismutase, and glutathione peroxidase, both of which were decreased by acetaminophen. Also, fucoidan decreased the expression of inflammatory mediators, including tumor necrosis factoralpha, interleukin 1 beta, and inducible nitric oxide synthase. Taken together, the data demonstrate the hepato-protective effects of fucoidan against acetaminophen-induced liver injury via anti-oxidant, anti-inflammatory, and anti-apoptotic mechanisms.

Chemokine Cxcl9 attenuates liver fibrosis-associated angiogenesis in mice

Recent data suggest that the chemokine receptor CXCR3 is functionally involved in fibroproliferative disorders, including liver fibrosis. Neoangiogenesis is an important pathophysiological feature of liver scarring, but a functional role of angiostatic CXCR3 chemokines in this process is unclear. We therefore investigated neoangiogenesis in carbon tetrachloride (CCl(4))-induced liver fibrosis in Cxcr3(-/-) and wildtype mice by histological, molecular, and functional imaging methods. Furthermore, we assessed the direct role of vascular endothelial growth factor (VEGF) overexpression on liver angiogenesis and the fibroproliferative response using a Tet-inducible bitransgenic mouse model. The feasibility of attenuation of angiogenesis and associated liver fibrosis by therapeutic treatment with the angiostatic chemokine Cxcl9 was systematically analyzed in vitro and in vivo. The results demonstrate that fibrosis progression in Cxcr3(-/-) mice was strongly linked to enhanced neoangiogenesis and VEGF/VEGFR2 expression compared with wildtype littermates. Systemic VEGF overexpression led to a fibrogenic response within the liver and was associated with a significantly increased Cxcl9 expression. In vitro, Cxcl9 displayed strong antiproliferative and antimigratory effects on VEGF-stimulated endothelial cells and stellate cells by way of reduced VEGFR2 (KDR), phospholipase Cγ (PLCγ), and extracellular signal-regulated kinase (ERK) phosphorylation, identifying this chemokine as a direct counter-regulatory molecule of VEGF signaling within the liver. Accordingly, systemic administration of Cxcl9 led to a strong attenuation of neoangiogenesis and experimental liver fibrosis in vivo. The results identify direct angiostatic and antifibrotic effects of the Cxcr3 ligand Cxcl9 in a model of experimental liver fibrosis. The amelioration of liver damage by systemic application of Cxcl9 might offer a novel therapeutic approach for chronic liver diseases associated with increased neoangiogenesis.

Beneficial effects of Jamaican bitter yam biomaterials in hypercholesterolemic mice

The Jamaican bitter yam (Dioscorea polygonoides) is one of the wild yam varieties found in Jamaica and is a rich source of saponins, a wide variety of phytochemicals known to possess potent hypocholesterolemic properties with associated lipoprotein redistribution. These phytochemicals have also been shown to display hepatoprotective properties. The study therefore examined the hypolipidemic and hepatoprotective effects of bitter yam biomaterials (BYB) supplementation. Hypercholesterolemic mice were placed in four groups of eight mice each while normocholesterolemic mice were placed in two groups of eight mice each. They were then fed diets with or without BYB supplementation. Hypercholesterolemic controls had significantly higher (P&lt;0.05) liver weights, serum total and LDL cholesterol, atherogenic index, lipid peroxidation in the livers and alkaline phosphatase and gamma glutaryl transferase activities when compared with normocholesterolemic controls. BYB supplementation led to significant reductions in all parameters except for the hepatomegaly experienced by the hypercholesterolemic controls. These results suggest that BYB supplementation may be beneficial in reversing the devastating effects of hypercholesterolemia and ameliorating liver damage.

The dopamine agonist piribedil exerts hepatoprotective effects on carbon tetrachloride-induced hepatic damage

This study aimed to investigate the effect of piribedil, a drug used for the treatment of Parkinson’s disease and which has direct dopaminergic stimulating action, on the acute hepatic injury in mice. Hepatotoxicity was induced by CCl4 orally (0.28 ml/kg). Piribedil at three dose levels (4.5, 9, or 18 mg/kg) or silymarin (25 mg/kg) was given orally daily for 7 days, starting at time of administration of CCl4. Liver damage was assessed by determining liver serum enzyme activities and by hepatic histopathology. Piribedil administration lessened the increases in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) and also prevented the development of hepatic necrosis caused by CCl4. The effect of piribedil was dose-dependent one. Piribedil administered at the above doses caused significant reduction in the elevated plasma ALT by −36.3%, −42.8%, and −52.4% and ALP by −25%, −36.9%, and −57.1%, respectively. AST decreased by −36.4% and −46.2% by piribedil at 9 or 18 mg/kg, respectively. In comparison, the elevated serum ALT, AST, and ALP levels decreased to −69.6%, −64.2%, and −68.5% of control values, respectively, by silymarin. Histopathologic examination of the livers of CCl4-treated mice administered piribedil at 9 mg/kg showed noticeable amelioration of the liver tissue damage, while piribedil at 18 mg/kg resulted in restoration of the normal architecture of the liver tissue as well as noticeable increase in the protein content of hepatocytes. It is concluded that administration of the dopaminergic agonist piribedil in a model of liver injury induced by CCl4 results in amelioration of liver damage.

Apoptosis: A barrier against cancer no more?

Apoptosis: A barrier against cancer no more?

Autophagy Suppresses Age-Dependent Ischemia and Reperfusion Injury in Livers of Mice

As life expectancy increases, there are greater numbers of patients with liver diseases who require surgery or transplantation. Livers of older patients have significantly less reparative capacity following ischemia and reperfusion (I/R) injury, which occurs during these operations. There are no strategies to reduce the age-dependent I/R injury. We investigated the role of autophagy in the age dependence of sensitivity to I/R injury. Hepatocytes and livers from 3- and 26-month-old mice were subjected to in vitro and in vivo I/R, respectively. We analyzed changes in autophagy-related proteins (Atg). Mitochondrial dysfunction was visualized using confocal and intravital multi-photon microscopy of isolated hepatocytes and livers from anesthetized mice, respectively. Immunoblot, autophagic flux, genetic, and imaging analyses all associated the increase in sensitivity to I/R injury with age with decreased autophagy and subsequent mitochondrial dysfunction due to calpain-mediated loss of Atg4B. Overexpression of either Atg4B or Beclin-1 recovered Atg4B, increased autophagy, blocked the onset of the mitochondrial permeability transition, and suppressed cell death after I/R in old hepatocytes. Coimmunoprecipitation analysis of hepatocytes and Atg3-knockout cells showed an interaction between Beclin-1 and Atg3, a protein required for autophagosome formation. Intravital multi-photon imaging revealed that overexpression of Beclin-1 or Atg4B attenuated autophagic defects and mitochondrial dysfunction in livers of older mice after I/R. Loss of Atg4B in livers of old mice increases their sensitivity to I/R injury. Increasing autophagy might ameliorate liver damage and restore mitochondrial function after I/R.

ANTIDIABETIC, ANTIATHEROSCLEROTIC AND HEPATOPROTECTIVE PROPERTIES OF DECALEPIS HAMILTONII IN STREPTOZOTOCIN-INDUCED DIABETIC RATS

ABSTRACT Decalepis root is consumed as ingredient in pickles and is a common ingredient in many of the ayurvedic preparation. Streptozotocin (STZ) is a potential source of oxidative stress that induces diabetes. In the present study, we have investigated the effect of Decalepis root extract (DRE) on antioxidant defence system in the body and other diabetic complications in rats. Rats were prefed with DRE (0.05 and 0.1%) and then injected with STZ (50 mg/kg bodyweight, i.p.). The results demonstrated that STZ injection lead to increased oxidation of tissue lipids apart from diabetic changes, decreased activities of the antioxidant enzymes causing liver and DNA damage. In rats, which were prefed with DRE, peroxidation of lipids was prevented to a significant level (heart 19%, kidney 42% and liver 88%). DRE protected the rats against STZ induced oxidative stress, reduced the risk of oxidative stress, DNA damage and ameliorated liver damage and diabetic condition. PRACTICAL APPLICATIONS The results obtained in this study clearly demonstrated that Decalepis root extract is plant-derived and nontoxic, it could be introduced in the cancer therapy regime in combination with conventional therapeutic agents, after some more detailed investigation. This extract could be used not only as food preservative (to replace for the toxic butylated hydroxyanisole and butylated hydroxytoluene currently under use) but also can be used in the preparation of nutraceutical and pharmaceutical products. Reactive oxygen species-mediated oxidative stress is now regarded as a major factor leading to degenerative diseases such as ageing, cardiovascular disease, cancer, diabetes, stroke, osteoporosis, diseases of the brain and nervous system and eye diseases such as cataract and age-related macular degeneration; a suitable antioxidant therapies with the extract could be one of the medicine to control these degenerative diseases. This study presents cost effective source of highly potent antioxidants that is safe and natural with antidiabetic, anti-atherosclerotic and hepatoprotective properties.

Essential Role for IL-27 Receptor Signaling in Prevention of Th1-Mediated Immunopathology during Malaria Infection

Successful resolution of malaria infection requires induction of proinflammatory immune responses that facilitate parasite clearance; however, failure to regulate this inflammation leads to immune-mediated pathology. The pathways that maintain this immunological balance during malaria infection remain poorly defined. In this study, we demonstrate that IL-27R-deficient (WSX-1(-/-)) mice are highly susceptible to Plasmodium berghei NK65 infection, developing exacerbated Th1-mediated immune responses, which, despite highly efficient parasite clearance, lead directly to severe liver pathology. Depletion of CD4(+) T cells---but not CD8(+) T cells---prevented liver pathology in infected WSX-1(-/-) mice. Although WSX-1 signaling was required for optimal IL-10 production by CD4(+) T cells, administration of rIL-10 failed to ameliorate liver damage in WSX-1(-/-) mice, indicating that additional, IL-10-independent, protective pathways are modulated by IL-27R signaling during malaria infection. These data are the first to demonstrate the essential role of IL-27R signaling in regulating effector T cell function during malaria infection and reveal a novel pathway that might be amenable to manipulation by drugs or vaccines.

Focal liver necrosis appears early after partial hepatectomy and is dependent on T cells and antigen delivery from the gut

Progressive liver failure may develop following removal of a large part of the liver or transplantation of a small for size liver graft. The pathophysiology of this clinical syndrome is only partially understood. We assessed liver damage and hepatocyte 5-bromo-2'-deoxyuridine (BrdU) incorporation following partial hepatectomy (PH) in C57BL/6, BALB/C and immune-deficient mice. Hepatic lymphocyte subpopulations were characterized. Lipopolysaccharide (LPS) treatment and bowel decontamination determined the role of gut antigens. Discrete, round necrotic lesions were observed as early as 2 h following 70%, but not 30% PH. In immune competent mice the extent of hepatocyte necrosis inversely correlated with BrdU incorporation. T, natural killer and natural killer T cells were recruited to the liver early after PH; however, only T-cell depletion abrogated hepatic necrosis. Hepatic injury was significantly reduced in non-obese diabetic/severe combined immunodeficient mice undergoing PH, while BrdU incorporation was not affected. Liver injury was augmented by LPS injection and reduced by gut decontamination. A distinct pattern of early focal hepatic necrosis is observed following extensive PH in mice. T cells infiltrating the liver immediately after PH and gut-derived antigens are indispensable for the observed liver necrosis and may thus provide therapeutic targets to ameliorate liver damage following PH.