Biologically active products of stimulated liver macrophages (Kupffer cells)

Therapeutic treatments for diabetes mellitus-induced liver injury by regulating oxidative stress and inflammation

Diabetes mellitus (DM) is a metabolic disease that affects all systems in the body, including the liver. Numerous studies have reported that chronic DM etiology and pathogenesis complications implicate oxidative stress, generating reactive oxygen species, such as superoxide anions and free radicals. In addition, pro-inflammatory reactions are also underlying functions closely related to oxidative stress that further exacerbate pathological DM states. The liver is especially susceptible to hyperglycemia-induced oxidative stress and the related inflammation. Thus, anti-oxidation and anti-inflammation therapies are promising strategies for treating liver damage. This review summarizes therapeutic treatments attenuating the generation of oxidative stress and pro-inflammation, which also cause DM-induced liver injury. Although the treatments have several impediments to be solved, these remedies may have clinically important implications under the absence of effective drugs for the damaged liver in DM patients.

Kupffer Cells as a Target for Immunotherapy

Kupffer cells (KCs) are resident macrophages in the liver. Recent studies have revealed that KCs are closely related to inflammatory liver diseases, including nonalcoholic liver diseases (NAFLD). From this point of view, KC transplantation can be a candidate for immunotherapy against inflammatory diseases. Similar to general macrophages, KCs show several different phenotypes according to their environment. Activated KCs are involved in either proinflammatory responses or anti-inflammatory responses. Thus, to manipulate KCs for immunotherapy, it is crucial to control the direction of KC activation. Here, we summarize the outlook and the issues hindering immunotherapy using KC transplantation.

Sex-specific behavioral, neurobiological, and cardiovascular responses to chronic social stress in mice

Psychosocial stress promotes and links mood and cardiovascular disorders in a sex-specific manner. However, findings in animal models are equivocal, in some cases opposing human dimorphisms. We examined central nervous system (CNS), behavioral, endocrine, cardiac, and hepatic outcomes in male or female C57Bl/6 mice subjected to chronic social stress (56 days of social isolation, with intermittent social confrontation encounters twice daily throughout the final 20 days). Females exhibited distinct physiological and behavioral changes, including relative weight loss, and increases in coronary resistance, hepatic inflammation, and thigmotaxic behavior in the open field. Males evidence reductions in coronary resistance and cardiac ischemic tolerance, with increased circulating and hippocampal monoamine levels and emerging anhedonia. Shared CNS gene responses include reduced hippocampal Maoa and increased Htr1b expression, while unique responses include repression of hypothalamic Ntrk1 and upregulation of cortical Nrf2 and Htr1b in females; and repression of hippocampal Drd1 and hypothalamic Gabra1 and Oprm in males. Declining cardiac stress resistance in males was associated with repression of cardiac leptin levels and metabolic, mitochondrial biogenesis, and anti-inflammatory gene expression. These integrated data reveal distinct biological responses to social stress in males and females, and collectively evidence greater biological disruption or allostatic load in females (consistent with propensities to stress-related mood and cardiovascular disorders in humans). Distinct stress biology, and molecular to organ responses, emphasize the importance of sex-specific mechanisms and potential approaches to stress-dependent disease.

Intercellular crosstalk of liver sinusoidal endothelial cells in liver fibrosis, cirrhosis and hepatocellular carcinoma

Intercellular crosstalk among various liver cells plays an important role in liver fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Capillarization of liver sinusoidal endothelial cells (LSECs) precedes fibrosis and accumulating evidence suggests that the crosstalk between LSECs and other liver cells is critical in the development and progression of liver fibrosis. LSECs dysfunction, a key event in the progression from fibrosis to cirrhosis, and subsequently obstruction of hepatic sinuses and increased intrahepatic vascular resistance (IHVR) contribute to development of portal hypertension (PHT) and cirrhosis. More importantly, immunosuppressive tumor microenvironment (TME), which is closely related to the crosstalk between LSECs and immune liver cells like CD8+ T cells, promotes advances tumorigenesis, especially HCC. However, the connections within the crosstalk between LSECs and other liver cells during the progression from liver fibrosis to cirrhosis to HCC have yet to be discussed. In this review, we first summarize the current knowledge of how different crosstalk between LSECs and other liver cells, including hepatocytes, hepatic stellate cells (HSCs), macrophoges, immune cells in liver and extra cellular matrix (ECM) contribute to the physiological function and the progrssion from liver fibrosis to cirrhosis, or even to HCC. Then we examine current treatment strategies for LSECs crosstalk in liver fibrosis, cirrhosis and HCC.

The Influence of Microenvironment on Survival of Intraportal Transplanted Islets

Clinical islet transplantation has the potential to cure type 1 diabetes. Despite recent therapeutic success, it is still uncommon because transplanted islets are damaged by multiple challenges, including instant blood mediated inflammatory reaction (IBMIR), inflammatory cytokines, hypoxia/reperfusion injury, and immune rejection. The transplantation microenvironment plays a vital role especially in intraportal islet transplantation. The identification and targeting of pathways that function as “master regulators” during deleterious inflammatory events after transplantation, and the induction of immune tolerance, are necessary to improve the survival of transplanted islets. In this article, we attempt to provide an overview of the influence of microenvironment on the survival of transplanted islets, as well as possible therapeutic targets.

New phthalimide analog ameliorates CCl4 induced hepatic injury in mice via reducing ROS formation, inflammation, and apoptosis

The present study aimed, for the first time, to examine the biochemical effects of new phthalimide analog, 2-[2-(2-Bromo-1-ethyl-1H-indol-3-yl) ethyl]-1H-isoindole-1,3(2H)-dione, compared to thalidomide drug against liver injury induced in mice. Carbon tetrachloride was intraperitoneal injected in mice for 6 consecutive weeks at a dose of 0.4 mL/kg twice a week for liver injury induction. Histopathological examination, levels of malondialdehyde, nitric oxide, and antioxidant enzymes were determined. Additionally, the protein levels of vascular endothelial growth factor, proliferating cell nuclear protein, tumor necrosis factor-alfa, nuclear factor kappa B-p65, B-cell lymphoma-2, and cysteine-aspartic acid protease-3 were determined. Results revealed that the treatment with phthalimide analog improved the detected liver damage and presented an obvious antioxidant activity through decreasing malondialdehyde and nitric oxide levels accompanied by increasing the levels of the antioxidant enzymes. Furthermore, the analog exhibited an effective inhibitory activity towards the studied protein expressions in liver tissues. Moreover, the B-cell lymphoma-2 protein level was increased while the cysteine-aspartic acid protease-3 level was suppressed after the treatment with phthalimide analog. Together, these results propose that phthalimide analog can ameliorate carbon tetrachloride-induced liver injury in mice through its potent inhibition mediating effect in oxidative stress, inflammation, and apoptosis mechanisms.

Functional kupffer cells migrate to the liver from the intraperitoneal cavity

We established a method of KC transplantation by intraperitoneal (i.p.) injection using EGFP-expressing cells (EGFP-KCs) and normal KCs. The novel method is easier and less invasive than conventional methods so that it is not only technically advantageous but also ethically preferable for experiments using animals. We demonstrated that KCs migrated to the liver following i.p. Injection. Engraftment in the liver was not observed for peritoneal macrophages (pMPs). This suggests that KCs migrate to the liver via a sorting mechanism. KC injection decreased the KC number at 24 h and then recovered the KCs at 10 days to a normal level. Additionally, recovery to the normal level by KC injection was observed in mice with KC depletion induced by GdCl3. These results suggest that a regulatory mechanism exists for controlling the number of KCs.

ARRB1 suppresses the activation of hepatic macrophages via modulating endoplasmic reticulum stress in lipopolysaccharide-induced acute liver injury

Acute liver injury (ALI) caused by multiple inflammatory responses is a monocyte-/macrophage-mediated liver injury that is associated with high morbidity and mortality. Liver macrophage activation is a vital event that triggers ALI. However, the mechanism of liver macrophage activation has not been fully elucidated. This study examined the role of β-arrestin1 (ARRB1) in wild-type (WT) and ARRB1-knockout (ARRB1-KO) mouse models of ALI induced by lipopolysaccharide (LPS), and ARRB1-KO mice exhibited more severe inflammatory injury and liver macrophage activation compared to WT mice. We found that LPS treatment reduced the expression level of ARRB1 in Raw264.7 and THP-1 cell lines, and mouse primary hepatic macrophages. Overexpression of ARRB1 in Raw264.7 and THP-1 cell lines significantly attenuated LPS-induced liver macrophage activation, such as transformation in cell morphology and enhanced expression of proinflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6), while downregulation of ARRB1 by small interfering RNA and ARRB1 deficiency in primary hepatic macrophages both aggravated macrophage activation. Moreover, overexpression of ARRB1 suppressed LPS-induced endoplasmic reticulum (ER) stress in liver macrophages, and inhibition of ER stress impeded excessive hepatic macrophage activation induced by downregulation of ARRB1. Our data demonstrate that ARRB1 relieves LPS-induced ALI through the ER stress pathway to regulate hepatic macrophage activation and that ARRB1 may be a potential therapeutic target for ALI.

Caffeine-induced inversion of prostaglandin E2 effects on hepatic stellate cell activation

BACKGROUND AND AIMS

Liver inflammation leads to the activation of hepatic stellate cells (HSCs), resulting in the development of liver fibrosis. The present study aimed to investigate the effects of prostaglandin E₂ (PGE₂), which is biosynthesized by Kupffer cells, hepatocytes, and HSCs during inflammation, on HSC activation, including its combinatory effect with caffeine.

METHODS

HSCs isolated from mice were activated by culturing in a medium supplemented with 10% fetal bovine serum for 7 days on plastic plates. The activation of HSCs was evaluated by immunofluorescence of α-smooth muscle actin in HSCs. Comprehensive gene expression analysis was performed using mRNA-sequencing to compare HSCs cultured for 1 or 7 days, with or without PGE₂, caffeine, or both.

RESULTS

PGE₂ (1 μM) facilitated the activation of HSCs but inhibited the HSC activation in the presence of caffeine (3 mM). Comprehensive gene expression analysis revealed that HSCs treated with PGE₂ in the presence of caffeine were classified in the same class as HSCs cultured for 1 day, i.e., quiescent HSCs. In contrast, PGE₂ did not exhibit an inhibitory effect on HSC activation when co-treated with any isoform-specific phosphodiesterase inhibitors. Although the adenylate cyclase inhibitor 2',5'-dideoxyadenosine suppressed the elevation of intracellular cAMP level induced by PGE₂ in the presence of caffeine, it had no effect on the inhibition of HSC activation by PGE₂ plus caffeine.

CONCLUSION

The effect of PGE₂ on HSC activation is changed from facilitatory to inhibitory when combined with caffeine, suggesting that caffeine may effectively suppress liver fibrosis during inflammation.

Diagnosis of mast cell activation syndrome: a global "consensus-2"

The concept that disease rooted principally in chronic aberrant constitutive and reactive activation of mast cells (MCs), without the gross MC neoplasia in mastocytosis, first emerged in the 1980s, but only in the last decade has recognition of "mast cell activation syndrome" (MCAS) grown significantly. Two principal proposals for diagnostic criteria have emerged. One, originally published in 2012, is labeled by its authors as a "consensus" (re-termed here as "consensus-1"). Another sizable contingent of investigators and practitioners favor a different approach (originally published in 2011, newly termed here as "consensus-2"), resembling "consensus-1" in some respects but differing in others, leading to substantial differences between these proposals in the numbers of patients qualifying for diagnosis (and thus treatment). Overdiagnosis by "consensus-2" criteria has potential to be problematic, but underdiagnosis by "consensus-1" criteria seems the far larger problem given (1) increasing appreciation that MCAS is prevalent (up to 17% of the general population), and (2) most MCAS patients, regardless of illness duration prior to diagnosis, can eventually identify treatment yielding sustained improvement. We analyze these proposals (and others) and suggest that, until careful research provides more definitive answers, diagnosis by either proposal is valid, reasonable, and helpful.

Alpha-1 antitrypsin suppresses macrophage activation and promotes islet graft survival after intrahepatic islet transplantation

Alpha-1 antitrypsin (AAT) has protective functions in animal islet transplantation models. While the therapeutic effect of AAT therapy is currently being tested in clinical trials, we investigated the mechanism of AAT protection in a clinically relevant marginal intrahepatic human islet transplantation model. In recipients receiving islets and AAT, 68.9% (20/29) reached normoglycemia, compared to 35.7% (10/28) in those receiving islets only, at 60 days posttransplant (PT). AAT-treated mice had lower serum levels of inflammatory cytokines immediately PT. Reduced M1 macrophages were observed in livers of AAT-treated recipients compared to controls as evidenced by flow cytometry and RNA-seq transcriptional profiling analysis. In vitro AAT suppressed IFN-γ-induced M1 macrophage activation/polarization via suppression of STAT1 phosphorylation and iNOS production. AAT inhibits macrophage activation induced by cytokines or dying islets, and consequently leads to islet cell survival. In a macrophage depletion mouse model, the presence of M1 macrophages in the liver contributed to graft death. AAT, through suppressing macrophage activation, protected transplanted islets from death and dysfunction in the human islet and NOD-SCID mouse model. The protective effect of AAT was confirmed in a major mismatch allogeneic islet transplantation model. Taken together, AAT suppresses liver macrophage activation that contributes to graft survival after transplantation.

Kupffer cell release of platelet activating factor drives dose limiting toxicities of nucleic acid nanocarriers

This work establishes that Kupffer cell release of platelet activating factor (PAF), a lipidic molecule with pro-inflammatory and vasoactive signaling properties, dictates dose-limiting siRNA nanocarrier-associated toxicities. High-dose intravenous injection of siRNA-polymer nano-polyplexes (si-NPs) elicited acute, shock-like symptoms in mice, associated with increased plasma PAF and consequently reduced PAF acetylhydrolase (PAF-AH) activity. These symptoms were completely prevented by prophylactic PAF receptor inhibition or Kupffer cell depletion. Assessment of varied si-NP chemistries confirmed that toxicity level correlated to relative uptake of the carrier by liver Kupffer cells and that this toxicity mechanism is dependent on carrier endosome disruptive function. 4T1 tumor-bearing mice, which exhibit increased circulating leukocytes, displayed greater sensitivity to these toxicities. PAF-mediated toxicities were generalizable to commercial delivery reagent in vivo-jetPEI® and an MC3 lipid formulation matched to an FDA-approved nanomedicine. These collective results establish Kupffer cell release of PAF as a key mediator of siRNA nanocarrier toxicity and identify PAFR inhibition as an effective strategy to increase siRNA nanocarrier tolerated dose.

Benefits and Detriments of Gadolinium from Medical Advances to Health and Ecological Risks

Gadolinium (Gd)-containing chelates have been established as diagnostics tools. However, extensive use in magnetic resonance imaging has led to increased Gd levels in industrialized parts of the world, adding to natural occurrence and causing environmental and health concerns. A vast amount of data shows that metal may accumulate in the human body and its deposition has been detected in organs such as brain and liver. Moreover, the disease nephrogenic systemic fibrosis has been linked to increased Gd³⁺ levels. Investigation of Gd³⁺ effects at the cellular and molecular levels mostly revolves around calcium-dependent proteins, since Gd³⁺ competes with calcium due to their similar size; other reports focus on interaction of Gd³⁺ with nucleic acids and carbohydrates. However, little is known about Gd³⁺ effects on membranes; yet some results suggest that Gd³⁺ interacts strongly with biologically-relevant lipids (e.g., brain membrane constituents) and causes serious structural changes including enhanced membrane rigidity and propensity for lipid fusion and aggregation at much lower concentrations than other ions, both toxic and essential. This review surveys the impact of the anthropogenic use of Gd emphasizing health risks and discussing debilitating effects of Gd³⁺ on cell membrane organization that may lead to deleterious health consequences.

Acute invariant NKT cell activation triggers an immune response that drives prominent changes in iron homeostasis

Iron homeostasis is an essential biological process that ensures the tissue distribution of iron for various cellular processes. As the major producer of hepcidin, the liver is central to the regulation of iron metabolism. The liver is also home to many immune cells, which upon activation may greatly impact iron metabolism. Here, we focus on the role of invariant natural killer T (iNKT) cells, a subset of T lymphocytes that, in mice, is most abundant in the liver. Activation of iNKT cells with the prototypical glycosphingolipid antigen, α-galactosylceramide, resulted in immune cell proliferation and biphasic changes in iron metabolism. This involved an early phase characterized by hypoferremia, hepcidin induction and ferroportin suppression, and a second phase associated with strong suppression of hepcidin despite elevated levels of circulating and tissue iron. We further show that these changes in iron metabolism are fully dependent on iNKT cell activation. Finally, we demonstrate that the biphasic regulation of hepcidin is independent of NK and Kupffer cells, and is initially driven by the STAT3 inflammatory pathway, whereas the second phase is regulated by repression of the BMP/SMAD signaling pathway. These findings indicate that iNKT activation and the resulting cell proliferation influence iron homeostasis.

Anti-Inflammatory Effects of Sulfated Polysaccharide from Sargassum Swartzii in Macrophages via Blocking TLR/NF-Κb Signal Transduction

This study involves enzymatic extraction of fucoidan from Sargassum swartzii and further purification via ion-exchange chromatography. The chemical and molecular characteristics of isolated fucoidan is evaluated concerning its anti-inflammatory potential in RAW 264.7 macrophages under LPS induced conditions. Structural properties of fucoidan were assessed via FTIR and NMR spectroscopy. NO production stimulated by LPS was significantly declined by fucoidan. This was witnessed to be achieved via fucoidan acting on mediators such as iNOS and COX-2 including pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), with dose dependent down-regulation. Further, the effect is exhibited by the suppression of TLR mediated MyD88, IKK complex, ultimately hindering NF-κB and MAPK activation, proposing its therapeutic applications in inflammation related disorders. The research findings provide an insight in relation to the sustainable utilization of fucoidan from marine brown algae S. swartzii as a potent anti-inflammatory agent in the nutritional, pharmaceutical, and cosmeceutical sectors.

Indole-3-Carbinol Derivative DIM Mitigates Carbon Tetrachloride-Induced Acute Liver Injury in Mice by Inhibiting Inflammatory Response, Apoptosis and Regulating Oxidative Stress

3,3'-Diindolylmethane (DIM), a metabolic product of indole-3-carbinol extracted from cruciferous vegetables exhibits anti-inflammatory and anti-cancer properties. Earlier, the product has been demonstrated to possess anti-fibrotic properties; however, its protective effects on liver injury have not been clearly elucidated. In this study, we postulated the effects and molecular mechanisms of action of DIM on carbon tetrachloride (CCl4)-induced liver injury in mice. Acute liver injury was induced by a single intraperitoneal administration of CCl4 (1 ml/kg) into mice. DIM was injected via subcutaneous route for three days at various doses (2.5, 5 and 10 mg/kg) before CCl4 injection. Mice were sacrificed and serum was collected for quantification of serum transaminases. The liver was collected and weighed. Treatment with DIM significantly reduced serum transaminases levels (AST and ALT), tumor necrosis factor-α (TNF-α) and reactive oxygen species (ROS). CCl4- induced apoptosis was inhibited by DIM treatment by the reduction in the levels of cleaved caspase-3 and Bcl2 associated X protein (Bax). DIM treated mice significantly restored Cytochrome P450 2E1, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression in CCl4 treated mice. In addition, DIM downregulated overexpression of hepatic nuclear factor kappa B (NF-κB) and inhibited CCl4 mediated apoptosis. Our results suggest that the protective effects of DIM against CCl4- induced liver injury are due to the inhibition of ROS, reduction of pro-inflammatory mediators and apoptosis.

Hepatic dysfunction after spinal cord injury: A vicious cycle of central and peripheral pathology?

The liver is essential for numerous physiological processes, including filtering blood from the intestines, metabolizing fats, proteins, carbohydrates and drugs, and regulating iron storage and release. The liver is also an important immune organ and plays a critical role in response to infection and injury throughout the body. Liver functions are regulated by autonomic parasympathetic innervation from the brainstem and sympathetic innervation from the thoracic spinal cord. Thus, spinal cord injury (SCI) at or above thoracic levels disrupts major regulatory mechanisms for hepatic functions. Work in rodents and humans shows that SCI induces liver pathology, including hepatic inflammation and fat accumulation characteristic of a serious form of non-alcoholic fatty liver disease (NAFLD) called non-alcoholic steatohepatitis (NASH). This hepatic pathology is associated with and likely contributes to indices of metabolic dysfunction often noted in SCI individuals, such as insulin resistance and hyperlipidemia. These occur at greater rates in the SCI population and can negatively impact health and quality of life. In this review, we will: 1) Discuss acute and chronic changes in human and rodent liver pathology and function after SCI; 2) Describe how these hepatic changes affect systemic inflammation, iron regulation and metabolic dysfunction after SCI; 3) Describe how disruption of the hepatic autonomic nervous system may be a key culprit in post-injury chronic liver pathology; and 4) Preview ongoing and future research that aims to elucidate mechanisms driving liver and metabolic dysfunction after SCI.

Pharmacological Benefits and Risk of Using Hormones in Organ Perfusion and Preservation Solutions in the Aspect of Minimizing Hepatic Ischemia-Reperfusion Injury during Storage

For several years, research has been carried out on the effectiveness of solutions for perfusion and preservation of organs, including the liver. There is a search for an optimal pharmacological composition of these solutions, allowing to preserve or improve vital functions of the organ for as long as possible until it is transplanted into a recipient. Hormones due to their properties, often resulting from their pleiotropic effects, may be a valuable component for optimizing the composition of liver perfusion and preservation solutions. The paper presents the current state of knowledge on liver perfusion and preservation solutions modified with hormones. It also shows the characteristics of the hormones evaluated, taking into account their physiological functions in the body.

Role of ghrelin on growth hormone/insulin-like growth factor-1 axis during endotoxemia

OBJECTIVE

To investigate the anti-inflammatory property of ghrelin treatment on the Growth Hormone (GH)/Insulin-like Growth Factor-I (IGF-1) axis in Wistar rats that have undergone endotoxemia.

DESIGN

In this randomized animal study, lipopolysaccharide (LPS) (5 mg/kg; intraperitoneal) was administered to induce endotoxemia, and ghrelin (15 nmol/kg; endovenous) was injected simultaneously. Blood and liver samples were collected 2 h, 6 h and 12 h after LPS administration for analysis.

MEASUREMENTS

Tumor necrosis factor alpha (TNF-α), interleukin (IL)-1, beta (IL-1β), and IL-6 from both blood and liver were determined by ELISA assay. Serum nitrate was determined by chemiluminescense. Growth hormone receptor (GHR) and growth hormone secretagogue receptor 1a (GHSR-1a) were determined by western blotting. GHR mRNA and IGF-1 mRNA were determined by RT-PCR.

RESULTS

LPS administration induced a decrease in IGF-1 and GH serum levels, characterizing GH/IGF-1 axis disruption. Ghrelin treatment attenuated the decrease of serum levels of IGF-1 as well as the increase of TNF-α, IL-1β, IL-6 and nitrate induced by LPS. The increase of induced GHSR-1a protein expression seen in the LPS group after 2 h remained until 6 h after ghrelin treatment. However, attenuation of the circulating IGF-1 decrease by ghrelin treatment was not accompanied by changes in GHR protein expression nor GHR and IGF-1 gene expression.

CONCLUSION

Ghrelin was able to attenuate changes in the GH/IGF-1 axis observed during systemic inflammation, which may be due to the modulation of pro-inflammatory mediators release.

Strategies to Circumvent Host Innate Immune Response by Hepatitis C Virus

Innate immune responses generate interferons, proinflammatory cytokines, complement activation, and natural killer (NK) cell response. Ultimately, this leads to the induction of a robust virus-specific adaptive immunity. Although the host innate immune system senses and responds to eliminate virus infection, hepatitis C virus (HCV) evades immune attack and establishes persistent infection within the liver. Spontaneous clearance of HCV infection is associated with a prompt induction of innate immunity generated in an infected host. In this review, we have highlighted the current knowledge of our understanding of host⁻HCV interactions, especially for endogenous interferon production, proinflammatory response, NK cell response, and complement activation, which may impair the generation of a strong adaptive immune response for establishment of chronicity. The information may provide novel strategies in augmenting therapeutic intervention against HCV.

Single versus double experimental bile duct ligation model for inducing bacterial translocation

BACKGROUND

Double common bile duct ligation plus section in rats is used as a model for bacterial translocation, a phenomenon that has been correlated with the degree of liver damage. This study analyzes whether a simpler variant of the technique is also a valid model to study bacterial translocation.

METHODS

Fifty-six male Sprague Dawley rats underwent one of three surgical interventions: a) proximal double ligation and section of the common bile duct; b) proximal simple ligation of the bile duct; and c) sham operation. Bacterial translocation was measured by cultures of mesenteric lymph nodes, blood, spleen and liver. Stool culture and histological analysis of liver damage were also performed.

RESULTS

The incidence of bacterial translocation in SBL and DBDL groups was 23,5% and 25% respectively. Mortality was similar between ligation groups (11.2% versus 10%). Liver cirrhosis developed in the group of double ligation and section (100% of the animals at 4 weeks), while portal hypertension appeared starting at week 3. None of the animals submitted to simple ligation developed liver cirrhosis.

CONCLUSIONS

Simple bile duct ligation is associated with a similar incidence of bacterial translocation as double ligation, but without cirrhosis or portal hypertension.

PPAR-gamma activation is associated with reduced liver ischemia-reperfusion injury and altered tissue-resident macrophages polarization in a mouse model

BACKGROUND

PPAR-gamma (γ) is highly expressed in macrophages and its activation affects their polarization. The effect of PPAR-γ activation on Kupffer cells (KCs) and liver ischemia-reperfusion injury (IRI) has not yet been evaluated. We investigated the effect of PPAR-γ activation on KC-polarization and IRI.

MATERIALS AND METHODS

Seventy percent (70%) liver ischemia was induced for 60mins. PPAR-γ-agonist or vehicle was administrated before reperfusion. PPAR-γ-antagonist was used to block PPAR-γ activation. Liver injury, necrosis, and apoptosis were assessed post-reperfusion. Flow-cytometry determined KC-phenotypes (pro-inflammatory Nitric Oxide +, anti-inflammatory CD206+ and anti-inflammatory IL-10+).

RESULTS

Liver injury assessed by serum AST was significantly decreased in PPAR-γ-agonist versus control group at all time points post reperfusion (1hr: 3092±105 vs 4469±551; p = 0.042; 6hr: 7041±1160 vs 12193±1143; p = 0.015; 12hr: 5746±328 vs 8608±1259; p = 0.049). Furthermore, liver apoptosis measured by TUNEL-staining was significantly reduced in PPAR-γ-agonist versus control group post reperfusion (1hr:2.46±0.49 vs 6.90±0.85%;p = 0.001; 6hr:26.40±2.93 vs 50.13±8.29%; p = 0.048). H&E staining demonstrated less necrosis in PPAR-γ-agonist versus control group (24hr:26.66±4.78 vs 45.62±4.57%; p = 0.032). The percentage of pro-inflammatory NO+ KCs was significantly lower at all post reperfusion time points in the PPAR-γ-agonist versus control group (1hr:28.49±4.99 vs 53.54±9.15%; p = 0.040; 6hr:5.51±0.54 vs 31.12±9.58%; p = 0.009; 24hr:4.15±1.50 vs 17.10±4.77%; p = 0.043). In contrast, percentage of anti-inflammatory CD206+ KCs was significantly higher in PPAR-γ-agonist versus control group prior to IRI (8.62±0.96 vs 4.88 ±0.50%; p = 0.04). Administration of PPAR-γ-antagonist reversed the beneficial effects on AST, apoptosis, and pro-inflammatory NO+ KCs.

CONCLUSION

PPAR-γ activation reduces IRI and decreases the pro-inflammatory NO+ Kupffer cells. PPAR-γ activation can become an important tool to improve outcomes in liver surgery through decreasing the pro-inflammatory phenotype of KCs and IRI.

Protective effect of an L-type calcium channel blocker, amlodipine, on paracetamol-induced hepatotoxicity in rats

Paracetamol (P), one of the most popular and commonly used analgesic and antipyretic agents, causes hepatotoxicity in overdoses. Amlodipine (AML), an L-type calcium channel blocker, has been shown to have anti-inflammatory activity by reversing the effect of calcium in the inflammation pathogenesis. In this study, the hepatoprotective activity of AML on P-induced hepatotoxicity was evaluated. Thirty male albino Wistar rats were divided into five groups: (1) control, (2) 2 g/kg of P, (3) 2 g/kg of P + 5 mg/kg of AML, (4) 2 g/kg of P + 10 mg/kg of AML, and (5) 10 mg/kg of AML. Some liver enzymes, oxidative parameters, cytokine mRNA expressions, histopathology, and immunohistochemical studies were performed in liver and blood samples. The serum levels of alanine aminotransferase and aspartate aminotransferase and the mRNA expression of tumor necrosis factor-alpha (TNF-α) and transforming growth factor-beta in the liver tissues were significantly increased in the group treated with P. The superoxide dismutase and glutathione parameters decreased and malondialdehyde levels increased in the livers of the rats treated with P. All these parameters were increased with both doses of the AML similar to the control group. A histopathological examination of the liver showed that AML administration ameliorated the P-induced inflammatory liver damage. In immunohistochemical staining, the expression of TNF-α in the cytoplasm of the hepatocytes was increased in the P group but not in other treatment groups when compared to the control. In conclusion, AML treatment showed significant protective effects against P-induced hepatotoxicity by increasing the activity of antioxidants and reducing inflammatory cytokines.

Houttuynia cordata Facilitates Metformin on Ameliorating Insulin Resistance Associated with Gut Microbiota Alteration in OLETF Rats

Metformin and Houttuynia cordata are representative anti-diabetic therapeutics in western and oriental medicine, respectively. The current study examined the synergistic anti-diabetic effect of Houttuynia cordata extraction (HCE) and metformin combination in Otsuka Long–Evans Tokushima Fatty (OLETF) rats. Fecal microbiota were analyzed by denaturing gradient gel electrophoresis (DGGE) and real-time PCR. Combining HCE + metformin resulted in significantly ameliorated glucose tolerance (oral glucose tolerance test (OGTT))—the same as metformin alone. Particularly, results of the insulin tolerance test (ITT) showed that combining HCE + metformin dramatically improved insulin sensitivity as compared to metformin treatment alone. Both fecal and serum endotoxin, as well as cytokines (tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6)) were significantly ameliorated by HCE + metformin compared to metformin alone. Meanwhile, the activation of AMPK (adenosine monophosphate-activated protein kinase) by metformin was distinctly enhanced by HCE. Both of HCE and metformin evidently changed the gut microbiota composition, causing the alteration of bacterial metabolite, like short-chain fatty acids. H. cordata, together with metformin, exerts intensive sensibilization to insulin; the corresponding mechanisms are associated with alleviation of endotoxemia via regulation of gut microbiota, particularly Roseburia, Akkermansia, and Gram-negative bacterium.

Augmented liver targeting of exosomes by surface modification with cationized pullulan

Exosomes are membrane nanoparticles containing biological substances that are employed as therapeutics in experimental inflammatory models. Surface modification of exosomes for better tissue targetability and enhancement of their therapeutic ability was recently attempted mainly using gene transfection techniques. Here, we show for the first time that the surface modification of exosomes with cationized pullulan, which has the ability to target hepatocyte asialoglycoprotein receptors, can target injured liver and enhance the therapeutic effect of exosomes. Surface modification can be achieved by a simple mixing of original exosomes and cationized pullulan and through an electrostatic interaction of both substances. The exosomes modified with cationized pullulan were internalized into HepG2 cells in vitro to a significantly greater extent than unmodified ones and this internalization was induced through the asialoglycoprotein receptor that was specifically expressed on HepG2 cells and hepatocytes. When injected intravenously into mice with concanavalin A-induced liver injury, the modified exosomes accumulated in the liver tissue, resulting in an enhanced anti-inflammatory effect in vivo. It is concluded that the surface modification with cationized pullulan promoted accumulation of the exosomes in the liver and the subsequent biological function, resulting in a greater therapeutic effect on liver injury.

STATEMENT OF SIGNIFICANCE

Exosomes have shown potentials as therapeutics for various inflammatory disease models. This study is the first to show the specific accumulation of exosomes in the liver and enhanced anti-inflammatory effect via the surface modification of exosomes using pullulan, which is specifically recognized by the asialoglycoprotein receptor (AGPR) on HepG2 cells and hepatocytes. The pullulan was expressed on the surface of PKH-labeled exosomes, and it led increased accumulation of PKH into HepG2 cells, whereas the accumulation was canceled by AGPR inhibitor. In the mouse liver injury model, the modification of PKH-labeled exosomes with pullulan enabled increased accumulation of PKH specifically in the injured liver. Furthermore the greater therapeutic effects against the liver injury compared with unmodified original exosomes was observed.

Effects of testosterone administration on liver structure and function in aging rats

Aging males have a decrease in testosterone levels, by which the testosterone treatment may influence in a negatively fashion the liver.

AIM

This study aimed to analyze the effects of aging with or without testosterone administration on the liver components of animals.

METHODS

Wistar rats were divided into three groups: 20 months' group (G20), 24 months' group (G24), group treated with testosterone for 16 weeks (GT). All groups were sacrificed at 24 months except for G20 that was sacrificed at 20 months.

RESULTS

Aging and testosterone treatment alters the body weight (BW), liver weight (LW) and relative liver weight. Besides, testosterone increased the mitogen capacity of hepatocytes. Nonetheless, we reinforce the negative effects of testosterone on old animals' liver as chronic hepatic congestion and/or cholestasis. In addition, we observed that testosterone plays an important role on hepatic glycogen stores.

CONCLUSIONS

Our study showed many implications for the knowledge about the effects of aging with or without testosterone administration on old animals' liver.

肝脏巨噬细胞及其在肝损伤中的作用

肝脏巨噬细胞来源和功能复杂, 包括肝脏固有巨噬细胞和单核细胞来源的浸润巨噬细胞, 在宿主防御机制及维持机体内环境稳定中起着重要作用, 也是参与肝脏损伤和修复的主要细胞成分. 解析不同来源肝脏巨噬细胞在不同病因导致肝损伤过程中表型分化、生物学作用的动态变化及其分子机制, 对理解肝损伤的病理过程, 探索以肝脏巨噬细胞为靶点预防和治疗肝损伤以及肝纤维化的方案具有重要意义.

Effects of purified zearalenone on selected immunological and histopathologic measurements of spleen in post-weanling gilts

The present study was aimed at investigating the adverse effects of dietary zearalenone (ZEA) on the lymphocyte proliferation rate (LPR), interleukin-2 (IL-2), mRNA expressions of pro-inflammatory cytokines, and histopathologic changes of spleen in post-weanling gilts. A total of 20 crossbred piglets (Yorkshire × Landrace × Duroc) with an initial BW of 10.36 ± 1.21 kg (21 d of age) were used in the study. Piglets were fed a basal diet with an addition of 0, 1.1, 2.0, or 3.2 mg/kg purified ZEA for 18 d ad libitum. The results showed that LPR and IL-2 production of spleen decreased linearly (P < 0.05) as dietary ZEA increased. Splenic mRNA expressions of interleukin-1β (IL-1β) and interleukin-6 (IL-6) were linearly up-regulated (P < 0.05) as dietary ZEA increased. On the contrary, linear down-regulation (P < 0.05) of mRNA expression of interferon-γ (IFN-γ) was observed as dietary ZEA increased. Swelling splenocyte in 1.1 mg/kg ZEA treatments, atrophy of white pulp and swelling of red pulp in 2.0 and 3.2 mg/kg ZEA treatments were observed. The cytoplasmic edema in 1.1 mg/kg ZEA treatments, significant chromatin deformation in 2.0 mg/kg ZEA treatment and phagocytosis in 3.2 mg/kg ZEA treatment were observed. Results suggested that dietary ZEA at 1.1 to 3.2 mg/kg can induce splenic damages and negatively affect immune function of spleen in post-weanling gilts.

HCV-induced regulatory alterations of IL-1β, IL-6, TNF-α, and IFN-ϒ operative, leading liver en-route to non-alcoholic steatohepatitis

Over the course of time, Hepatitis C has become a universal health menace. Its deleterious effects on human liver encompass a lot of physiological, genetic as well as epigenetic alterations. Fatty liver (Hepatic steatosis) is an inflammation having multifactorial ancestries; one of them is HCV (steatohepatitis). HCV boosts several cellular pathways involving up-regulation of a number of cytokines. Current study reviews the regulation of some selective key cytokines during HCV infection, to help generate an improved understanding of their role. These cytokines, IL-1β, IL-6, TNF-α, and IFN-ϒ, are inflammatory markers of the body. These particular markers along with others help hepatocytes against viral infestation. However, recently, their association has been found in degradation of liver on the trail heading to non-alcoholic steatohepatitis (NASH). Consequently, the disturbance in their equilibrium has been repeatedly reported during HCV infection. Quite a number of findings are affirming their up-regulation. Although these cell markers are stimulated by hepatocytes as their standard protection mechanism, but modern studies have testified the paradoxical nature of this defense line. Nevertheless, direct molecular or epigenetic research is needed to question the actual molecular progressions and directions commanding liver to steatosis, cirrhosis, or eventually HCC (Hepatocellular Carcinoma).

Isofraxidin, a coumarin component improves high-fat diet induced hepatic lipid homeostasis disorder and macrophage inflammation in mice

Isofraxidin (IF) is a coumarin compound produced in the functional foodsSiberian ginsengandApium graveolens.

Bone Marrow Cell Transplant From Donors With Cardiovascular Risk Factors Increases the Pro-atherosclerotic Phenotype in the Recipients

Improvement of long-term survival after hematopoietic stem cell transplantation has revealed that these patients have an increased appearance of de novo cardiovascular risk factors. Even though in these clinical studies no relation to transplant-related factors has been found, no attention has been paid to the influence of cardiovascular risk factors affecting the bone marrow donors on the cardiovascular risk of the recipients. Thus, the aim of this study was to analyze, using an animal model, whether transplantation of bone marrow from donors with cardiovascular risk factors increases cardiovascular risk in healthy recipients. Results from transplantation experiments have shown that bone marrow from donors with cardiovascular risk factors induced pro-atherogenic modifications in the cholesterol profile of healthy recipients, increasing the low-density lipoprotein cholesterol fraction in comparison to those transplanted with control bone marrow. Moreover, bone marrow from donors with cardiovascular risk factors induced significant alterations in liver pro-inflammatory state and lipid metabolism-related gene expression that could contribute to alter cholesterol homeostasis. Altogether, these results suggest that cardiovascular risk factors in the donor confer a cardiometabolic alteration to their bone marrow cells that is transferred to noncardiovascular disease transplant recipients, affecting their liver function and increasing their cardiovascular risk.

Immunosuppressive effect of mesenchymal stem cell-derived exosomes on a concanavalin A-induced liver injury model

BACKGROUND

This study aimed to evaluate the effect of mesenchymal stem cell (MSC)-derived exosomes on an immune-induced liver injury model. MSCs show a unique function to modulate immune reaction although the molecular mechanisms are still under investigation. Exosomes are a nanoparticle containing microRNA and many ligands and are recognized as important factors secreted from MSC to express their function. This research is undertaken to evaluate the effect of MSC-derived exosome on concanavalin-A (con-A)-induced liver injury.

METHODS

Exosomes were collected from the supernatant of MSC from the bone marrow of C57B6 mice with ultracentrifugation. The collected exosomes or MSCs were injected intravenously into liver injury mice that had been prepared by the intravenous con-A injection. Liver and serum samples were collected 24 h later to evaluate the macro- and microscopic images, the alanine aminotransferase (ALT), and cytokine messenger RNA (mRNA) expression levels. Phenotypical change of non-parenchymal liver cells was also evaluated by flow cytometry. Liver localization of PKH26 after the injection of PKH26-labeled exosomes or MSCs was observed by microscope. Each result was statistically analyzed with Student's t test.

RESULTS

PKH was observed in the liver after PKH-labeled exosomes were injected into mouse, whereas it was only observed in the lung in a mouse group receiving PKH-leveled MSC. There were decreases in ALT, liver necrotic areas, and the extent of apoptosis indicated by the single-stranded DNA index of groups that received multiple injections of MSC-derived exosomes, but an increase in the Ki-67 index. The mRNA expression of anti-inflammatory cytokines was enhanced. The number of Treg was increased among NPCs in a group receiving exosomes multiple times.

CONCLUSIONS

Suppression of con-A-induced liver injury by injection of exosomes was observed as same extent as MSC. Considering the advantage of exosomes as its non-living nature and dosing adjustability over MSC, exosome will be one alternative of MSC transplantation.

Mesenchymal stem cells improve mouse non-heart-beating liver graft survival by inhibiting Kupffer cell apoptosis via TLR4-ERK1/2-Fas/FasL-caspase3 pathway regulation

Background

Liver transplantation is the optimal treatment option for end-stage liver disease, but organ shortages dramatically restrict its application. Donation after cardiac death (DCD) is an alternative approach that may expand the donor pool, but it faces challenges such as graft dysfunction, early graft loss, and cholangiopathy. Moreover, DCD liver grafts are no longer eligible for transplantation after their warm ischaemic time exceeds 30 min. Mesenchymal stem cells (MSCs) have been proposed as a promising therapy for treatment of certain liver diseases, but the role of MSCs in DCD liver graft function remains elusive.

Methods

In this study, we established an arterialized mouse non-heart-beating (NHB) liver transplantation model, and compared survival rates, cytokine and chemokine expression, histology, and the results of in vitro co-culture experiments in animals with or without MSC infusion.

Results

MSCs markedly ameliorated NHB liver graft injury and improved survival post-transplantation. Additionally, MSCs suppressed Kupffer cell apoptosis, Th1/Th17 immune responses, chemokine expression, and inflammatory cell infiltration. In vitro, PGE2 secreted by MSCs inhibited Kupffer cell apoptosis via TLR4-ERK1/2-caspase3 pathway regulation.

Conclusion

Our study uncovers a protective role for MSCs and elucidates the underlying immunomodulatory mechanism in an NHB liver transplantation model. Our results suggest that MSCs are uniquely positioned for use in future clinical studies owing to their ability to protect DCD liver grafts, particularly in patients for whom DCD organs are not an option according to current criteria.

Mesenchymal stem cells improve mouse non-heart-beating liver graft survival by inhibiting Kupffer cell apoptosis via TLR4-ERK1/2-Fas/FasL-caspase3 pathway regulation

BACKGROUND

Liver transplantation is the optimal treatment option for end-stage liver disease, but organ shortages dramatically restrict its application. Donation after cardiac death (DCD) is an alternative approach that may expand the donor pool, but it faces challenges such as graft dysfunction, early graft loss, and cholangiopathy. Moreover, DCD liver grafts are no longer eligible for transplantation after their warm ischaemic time exceeds 30 min. Mesenchymal stem cells (MSCs) have been proposed as a promising therapy for treatment of certain liver diseases, but the role of MSCs in DCD liver graft function remains elusive.

METHODS

In this study, we established an arterialized mouse non-heart-beating (NHB) liver transplantation model, and compared survival rates, cytokine and chemokine expression, histology, and the results of in vitro co-culture experiments in animals with or without MSC infusion.

RESULTS

MSCs markedly ameliorated NHB liver graft injury and improved survival post-transplantation. Additionally, MSCs suppressed Kupffer cell apoptosis, Th1/Th17 immune responses, chemokine expression, and inflammatory cell infiltration. In vitro, PGE2 secreted by MSCs inhibited Kupffer cell apoptosis via TLR4-ERK1/2-caspase3 pathway regulation.

CONCLUSION

Our study uncovers a protective role for MSCs and elucidates the underlying immunomodulatory mechanism in an NHB liver transplantation model. Our results suggest that MSCs are uniquely positioned for use in future clinical studies owing to their ability to protect DCD liver grafts, particularly in patients for whom DCD organs are not an option according to current criteria.

Therapeutic potential of the immunomodulatory proteins Wuchereria bancrofti L2 and Brugia malayi abundant larval transcript 2 against streptozotocin-induced type 1 diabetes in mice

Epidemiological and experimental evidence has supported the concept of using helminths as alternative bio-therapeutic agents in the treatment of type 1 diabetes (T1D). In the current study, two filarial proteins, recombinant Wuchereria bancrofti L2 (rWbL2) and Brugia malayi abundant larval transcript 2 (rBmALT-2) have been investigated, individually and in combination, for their therapeutic potential in streptozotocin (STZ)-induced T1D. The rWbL2 and rBmALT-2 proteins, when administered individually or in combination, have resulted in lowering of the blood glucose levels and reducing the incidence of T1D in mice. In addition, these proteins have led to reduced lymphocytic infiltration and decreased islet damage and inflammation. The curative effect was found to be associated with the suppression of release of tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), and increased production of interleukin (IL)-4, IL-5 and IL-10 cytokines by the splenocytes of the diabetic mice. Insulin-specific IgG1 and antigen-specific IgE antibodies were found to be elevated in the sera of mice treated with rWbL2 and rBmALT-2 proteins. From the findings in this study, it can be envisaged that both of these filarial immunomodulatory proteins have the potential to ameliorate T1D by altering the regulatory immune responses.

Investigating the Responses of Human Epithelial Cells to Predatory Bacteria

One beguiling alternative to antibiotics for treating multi-drug resistant infections are Bdellovibrio-and-like-organisms (BALOs), predatory bacteria known to attack human pathogens. Consequently, in this study, the responses from four cell lines (three human and one mouse) were characterized during an exposure to different predatory bacteria, Bdellovibrio bacteriovorus HD100, Bacteriovorus BY1 and Bacteriovorax stolpii EB1. TNF-α levels were induced in Raw 264.7 mouse macrophage cultures with each predator, but paled in comparison to those obtained with E. coli. This was true even though the latter strain was added at an 11.1-fold lower concentration (p < 0.01). Likewise, E. coli led to a significant (54%) loss in the Raw 264.7 murine macrophage viability while the predatory strains had no impact. Tests with various epithelial cells, including NuLi-1 airway, Caco2, HT29 and T84 colorectal cells, gave similar results, with E. coli inducing IL-8 production. The viabilities of the NuLi-1 and Caco-2 cells were slightly reduced (8%) when exposed to the predators, while T84 viability remained steady. In no cases did the predatory bacteria induce actin rearrangement. These results clearly demonstrate the gentle natures of predatory bacteria and their impacts on human cells.

Hyaluronan accumulates around portal vessels in liver after endotoxin treatment of rats

Livers of normal rats and rats treated with lipopolysaccharide from Escherichia coli were isolated in situ and tested for capability to extract [3H]-hyaluronan. In control livers, excess unlabeled hyaluronan inhibited extraction of [3H]-hyaluronan both at 4°C and 37°C. Furthermore, part of the [3H]-hyaluronan extracted at 4°C could be released by subsequent perfusion with excess of unlabeled hyaluronan. This behaviour is in accordance with the well-characterized receptor-mediated uptake of hyaluronan in sinusoidal endothelial cells. However, in lipopolysaccharide-treated animals, the uptake of [3H]-hyaluronan was not inhibited by unlabelled polysaccharide, nor could [3H]-hyaluronan bound at 4°C be released from its binding sites. Both types of livers were perfused with 10 μg/ml of hyaluronan and recovered for histology. An accumulation of hyaluronan in areas around portal veins was found in endotoxin treated rats, while only traces of hyaluronan could be visualized in the vessels of normal livers. The location of hyaluronan coincided with cell infiltrates. Thus, there is a different mechanism for liver clearance of hyaluronan in the endotoxic animal.

Immune response to bovine viral diarrhea virus--looking at newly defined targets

Bovine viral diarrhea virus (BVDV) has long been associated with a wide variety of clinical syndromes and immune dysregulation, many which result in secondary bacterial infections. Current understanding of immune cell interactions that result in activation and tolerance are explored in light of BVDV infection including: depletion of lymphocytes, effects on neutrophils, natural killer cells, and the role of receptors and cytokines. In addition, we review some new information on the effect of BVDV on immune development in the fetal liver, the role of resident macrophages, and greater implications for persistent infection.

Interleukin 18 binding protein ameliorates ischemia/reperfusion-induced hepatic injury in mice

Inflammation-associated oxidative stress contributes to hepatic ischemia/reperfusion injury (IRI). Detrimental inflammatory event cascades largely depend on activated Kupffer cells (KCs) and neutrophils, as well as proinflammatory cytokines, including tumor necrosis factor α (TNF-α) and interleukin (IL) 18. The aim of our study was to evaluate the effects of IL 18 binding protein (IL 18Bp) in hepatic IRI of mice. Thirty C57BL/6 mice were allocated into 3 groups: sham operation, ischemia/reperfusion (I/R), and I/R with intravenous administration of IL 18Bp. Hepatic ischemia was induced for 30 minutes by Pringle's maneuver. After 120 minutes of reperfusion, mice were euthanized, and the liver and blood samples were collected for histological, immunohistochemical, molecular, and biochemical analyses. I/R injury induced the typical liver pathology and upregulated IL-18 expression in the liver of mice. Binding of IL 18 with IL 18Bp significantly reduced the histopathological indices of I/R liver injury and KC apoptosis. The I/R-induced increase of TNF-α, malondialdehyde, aspartate aminotransferase, and alanine aminotransferase levels was prevented in statistically significant levels because of the pretreatment with IL 18Bp. Likewise, blocking of IL 18 ablated the I/R-associated elevation of nuclear factor kappa B, c-Jun, myeloperoxidase, and IL 32 and the up-regulation of neutrophils and T-helper lymphocytes. Administration of IL 18Bp protects the mice liver from I/R injury by intervening in critical inflammation-associated pathways and KC apoptosis.

Genetic background in nonalcoholic fatty liver disease: A comprehensive review

In the Western world, nonalcoholic fatty liver disease (NAFLD) is considered as one of the most significant liver diseases of the twenty-first century. Its development is certainly driven by environmental factors, but it is also regulated by genetic background. The role of heritability has been widely demonstrated by several epidemiological, familial, and twin studies and case series, and likely reflects the wide inter-individual and inter-ethnic genetic variability in systemic metabolism and wound healing response processes. Consistent with this idea, genome-wide association studies have clearly identified Patatin-like phosholipase domain-containing 3 gene variant I148M as a major player in the development and progression of NAFLD. More recently, the transmembrane 6 superfamily member 2 E167K variant emerged as a relevant contributor in both NAFLD pathogenesis and cardiovascular outcomes. Furthermore, numerous case-control studies have been performed to elucidate the potential role of candidate genes in the pathogenesis and progression of fatty liver, although findings are sometimes contradictory. Accordingly, we performed a comprehensive literature search and review on the role of genetics in NAFLD. We emphasize the strengths and weaknesses of the available literature and outline the putative role of each genetic variant in influencing susceptibility and/or progression of the disease.

Alcoholic Liver Disease: Role of Cytokines

The present review spans a broad spectrum of topics dealing with alcoholic liver disease (ALD), including clinical and translational research. It focuses on the role of the immune system and the signaling pathways of cytokines in the pathogenesis of ALD. An additional factor that contributes to the pathogenesis of ALD is lipopolysaccharide (LPS), which plays a central role in the induction of steatosis, inflammation, and fibrosis in the liver. LPS derived from the intestinal microbiota enters the portal circulation, and is recognized by macrophages (Kupffer cells) and hepatocytes. In individuals with ALD, excessive levels of LPS in the liver affect immune, parenchymal, and non-immune cells, which in turn release various inflammatory cytokines and recruit neutrophils and other inflammatory cells. In this review, we elucidate the mechanisms by which alcohol contributes to the activation of Kupffer cells and the inflammatory cascade. The role of the stellate cells in fibrogenesis is also discussed.