Hepatic steatosis and insulin resistance are associated with serum imbalance of adiponectin/tumour necrosis factor-alpha in chronic hepatitis C patients

Immunosenescence in atherosclerosis: A role for chronic viral infections

Immune system is a versatile and dynamic body organ which offers survival and endurance of human beings in their hostile living environment. However, similar to other cells, immune cells are hijacked by senescence. The ageing immune cells lose their beneficial functions but continue to produce inflammatory mediators which draw other immune and non-immune cells to the senescence loop. Immunosenescence has been shown to be associated with different pathological conditions and diseases, among which atherosclerosis has recently come to light. There are common drivers of both immunosenescence and atherosclerosis; e.g. inflammation, reactive oxygen species (ROS), chronic viral infections, genomic damage, oxidized-LDL, hypertension, cigarette smoke, hyperglycaemia, and mitochondrial failure. Chronic viral infections induce inflammaging, sustained cytokine signaling, ROS generation and DNA damage which are associated with atherogenesis. Accumulating evidence shows that several DNA and RNA viruses are stimulators of immunosenescence and atherosclerosis in an interrelated network. DNA viruses such as CMV, EBV and HBV upregulate p16, p21 and p53 senescence-associated molecules; induce inflammaging, metabolic reprogramming of infected cells, replicative senescence and telomere shortening. RNA viruses such as HCV and HIV induce ROS generation, DNA damage, induction of senescence-associated secretory phenotype (SASP), metabolic reprogramming of infected cells, G1 cell cycle arrest, telomere shortening, as well as epigenetic modifications of DNA and histones. The newly emerged SARS-CoV-2 virus is also a potent inducer of cytokine storm and SASP. The spike protein of SARS-CoV-2 promotes senescence phenotype in endothelial cells by augmenting p16, p21, senescence-associated β-galactosidase (SA-β-Gal) and adhesion molecules expression. The impact of SARS-CoV-2 mega-inflammation on atherogenesis, however, remains to be investigated. In this review we focus on the common processes in immunosenescence and atherogenesis caused by chronic viral infections and discuss the current knowledge on this topic.

Impact of direct-acting antiviral regimens on hepatic and extrahepatic manifestations of hepatitis C virus infection

Hepatitis C virus (HCV) is a common cause of liver disease and is associated with various extrahepatic manifestations (EHMs). This mini-review outlines the currently available treatments for HCV infection and their prognostic effect on hepatic manifestations and EHMs. Direct-acting antiviral (DAA) regimens are considered pan-genotypic as they achieve a sustained virological response (SVR) > 85% after 12 wk through all the major HCV genotypes, with high percentages of SVR even in advanced fibrosis and cirrhosis. The risk factors for DAA failure include old males, cirrhosis, and the presence of resistance-associated substitutions (RAS) in the region targeted by the received DAAs. The effectiveness of DAA regimens is reduced in HCV genotype 3 with baseline RAS like A30K, Y93H, and P53del. Moreover, the European Association for the Study of the Liver recommended the identification of baseline RAS for HCV genotype 1a. The higher rate of hepatocellular carcinoma (HCC) after DAA therapy may be related to the fact that DAA regimens are offered to patients with advanced liver fibrosis and cirrhosis, where interferon was contraindicated to those patients. The change in the growth of pre-existing subclinical, undetectable HCC upon DAA treatment might be also a cause. Furthermore, after DAA therapy, the T cell-dependent immune response is much weaker upon HCV clearance, and the down-regulation of TNF-α or the elevated neutrophil to lymphocyte ratio might increase the risk of HCC. DAAs can result in reactivation of hepatitis B virus (HBV) in HCV co-infected patients. DAAs are effective in treating HCV-associated mixed cryoglobulinemia, with clinical and immunological responses, and have rapid and high effectiveness in thrombocytopenia. DAAs improve insulin resistance in 90% of patients, increase glomerular filtration rate, and decrease proteinuria, hematuria and articular manifestations. HCV clearance by DAAs allows a significant improvement in atherosclerosis and metabolic and immunological conditions, with a reduction of major cardiovascular events. They also improve physical function, fatigue, cognitive impairment, and quality of life. Early therapeutic approach with DAAs is recommended as it cure many of the EHMs that are still in a reversible stage and can prevent others that can develop due to delayed treatment.

Dengue virus is involved in insulin resistance via the downregulation of IRS-1 by inducing TNF-α secretion

During the epidemic, the individuals with underlying diseases usually have a higher rate of mortality. Diabetes is highly prevalent worldwide, making it a frequent comorbidity in dengue fever patients. Therefore, understanding the relationship between dengue virus (DENV) infection and diabetes is important. We first demonstrated that DENV-3 infection down-regulated the expression of IRS-1. In vitro, treatment of HepG2 cells with TNF-α inhibitors and siRNA proved that after DENV-3 infection in HepG2 cells, cellular TNF-α secretion was increased, which negatively regulated IRS-1, thereby leading to an insulin-resistant state. In vivo, DENV-3 induced insulin resistance (IR) in hepatocytes by promoting the secretion of TNF-α and inhibiting the expression of IRS-1 was proved. In vivo approaches also showed that after DENV-3 infection, TNF-α levels in the serum of C57BL/6 mice with insulin resistance increased, and upon TNF-α antagonist III treatment, IRS-1 expression in the liver, reduced by infection, was upregulated. In addition, transcriptomic analysis revealed more negative regulatory events in the insulin receptor signaling pathway after DENV-3 infection. This is the first report of a link between DENV-3 infection and insulin resistance, and it lays a foundation for further research.

Cardiovascular Implications of Immune Disorders in Women

Immune responses differ between men and women, with women at higher risk of developing chronic autoimmune diseases and having more robust immune responses to many viruses, including HIV and hepatitis C virus. Although immune dysregulation plays a prominent role in chronic systemic inflammation, a key driver in the development of atherosclerotic cardiovascular disease (ASCVD), standard ASCVD risk prediction scores underestimate risk in populations with immune disorders, particularly women. This review focuses on the ASCVD implications of immune dysregulation due to disorders with varying global prevalence by sex: autoimmune disorders (female predominant), HIV (male-female equivalent), and hepatitis C virus (male predominant). Factors contributing to ASCVD in women with immune disorders, including traditional risk factors, dysregulated innate and adaptive immunity, sex hormones, and treatment modalities, are discussed. Finally, the need to develop new ASCVD risk stratification tools that incorporate variables specific to populations with chronic immune disorders, particularly in women, is emphasized.

Heart Failure in Chronic Infectious and Inflammatory Conditions: Mechanistic Insights from Clinical Heterogeneity

PURPOSE OF REVIEW

The balance between inflammation and its resolution plays an important and increasingly appreciated role in heart failure (HF) pathogenesis. In humans, different chronic inflammatory conditions and immune-inflammatory responses to infection can lead to diverse HF manifestations. Reviewing the phenotypic and mechanistic diversity of these HF presentations offers useful clinical and scientific insights.

RECENT FINDINGS

HF risk is increased in patients with chronic inflammatory and autoimmune disorders and relates to disease severity. Inflammatory condition-specific HF manifestations exist and underlying pathophysiologic causes may differ across conditions. Although inflammatory disease-specific presentations of HF differ, chronic excess in inflammation and auto-inflammation relative to resolution of this inflammation is a common underlying contributor to HF. Further studies are needed to phenotypically refine inflammatory condition-specific HF pathophysiologies and prognoses, as well as potential targets for intervention.

Impact of sustained virological response on metabolic disorders in diabetic chronic hepatitis C virus patients after treatment with generic sofosbuvir and daclatasvir

OBJECTIVES

To evaluate the effect of generic sofosbuvir and daclatasvir (SOF/DCV) treatment on the glycemic state and insulin resistance as well as lipid profiles of those who achieved sustained virological response (SVR) in diabetic chronic hepatitis C virus (CHC) patients.

METHODS

We retrospectively reviewed 114 CHC patients with evidence of type 2 diabetes that were treated with generic SOF/DCV between May 2016 and August 2017. Baseline demographic and laboratory data were recorded. At 12-week post end of therapy (SVR12), glycemic state and insulin resistance as well as lipid profiles were re-evaluated and compared with baseline.

RESULTS

A total of 98 diabetic CHC patients were finally included and were responders. A significant decline in the glycemic state as well as Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) values (P ≤ 0.0001) was observed, but HOMA-S showed a statistically significant increase (P ≤ 0.0001) at SVR12 in comparison to baseline values. Also, a significant increase in serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol levels was observed at SVR12 compared to baseline, but serum triglycerides levels showed a significant decrease. Logistic regression showed that the higher baseline HOMA-IR was a significant predictive variable of a decrease ≥20% of HOMA-IR, while higher baseline HOMA-IR and baseline triglycerides emerged as the only significant predictors of the Δ increase LDL-C level at SVR12.

CONCLUSION

SOF/DCV-based therapy led to an improvement of glycemic state associated with a global worsening of lipid profile. Further studies are strongly warranted to evaluate the cardiovascular balance between amelioration of insulin resistance and negative changes of the lipid profile.

Metabolic complications of hepatitis C virus infection

Hepatitis C virus (HCV) infection is a systemic disease that is implicated in multiple extrahepatic organ dysfunction contributing to its protean manifestations. HCV is associated with diverse extrahepatic disorders including atherosclerosis, glucose and lipid metabolic disturbances, alterations in the iron metabolic pathways, and lymphoproliferative diseases over and above the traditional liver manifestations of cirrhosis and hepatocellular carcinoma. The orchestration between HCV major proteins and the liver-muscle-adipose axis, poses a major burden on the global health of human body organs, if not adequately addressed. The close and inseparable associations between chronic HCV infection, metabolic disease, and cardiovascular disorders are specifically important considering the increasing prevalence of obesity and metabolic syndrome, and their economic burden to patients, the healthcare systems, and society. Cellular and molecular mechanisms governing the interplay of these organs and tissues in health and disease are therefore of significant interest. The coexistence of metabolic disorders and chronic hepatitis C infection also enhances the progression to liver fibrosis and hepatocellular carcinoma. The presence of metabolic disorders is believed to influence the chronicity and virulence of HCV leading to liver disease progression. This comprehensive review highlights current knowledge on the metabolic manifestations of hepatitis C and the potential pathways in which these metabolic changes can influence the natural history of the disease.

Roles of Adipokines in Digestive Diseases: Markers of Inflammation, Metabolic Alteration and Disease Progression

Adipose tissue is a highly dynamic endocrine tissue and constitutes a central node in the interorgan crosstalk network through adipokines, which cause pleiotropic effects, including the modulation of angiogenesis, metabolism, and inflammation. Specifically, digestive cancers grow anatomically near adipose tissue. During their interaction with cancer cells, adipocytes are reprogrammed into cancer-associated adipocytes and secrete adipokines to affect tumor cells. Moreover, the liver is the central metabolic hub. Adipose tissue and the liver cooperatively regulate whole-body energy homeostasis via adipokines. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, is currently considered a global epidemic and is related to low-grade systemic inflammation characterized by altered adipokine regulation. Obesity-related digestive diseases, including gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyps and cancer, non-alcoholic fatty liver disease, viral hepatitis-related diseases, cholelithiasis, gallbladder cancer, cholangiocarcinoma, pancreatic cancer, and diabetes, might cause specific alterations in adipokine profiles. These patterns and associated bases potentially contribute to the identification of prognostic biomarkers and therapeutic approaches for the associated digestive diseases. This review highlights important findings about altered adipokine profiles relevant to digestive diseases, including hepatic, pancreatic, gastrointestinal, and biliary tract diseases, with a perspective on clinical implications and mechanistic explorations.

The Effect of Viral Clearance Achieved by Direct-Acting Antiviral Agents on Hepatitis C Virus Positive Patients with Type 2 Diabetes Mellitus: A Word of Caution after the Initial Enthusiasm

The causal link between chronic hepatitis C and glycometabolic alterations has been confirmed by much biochemical, clinical, and epidemiological research work, but what is still controversial is the long-term clinical impact of sustained virologic response (SVR) achieved by direct-acting antiviral agents (DAAs) on patients with type 2 diabetes mellitus (DM). The aim of this paper is to summarize the biochemical and clinical consequences to DM of DAA-based therapy for hepatitis C virus (HCV) infection. An electronic search of Embase, PubMed, MEDLINE, Ovid, and the Cochrane Database of Systematic Reviews was conducted for publications assessing whether clearance of HCV achieved by interferon (IFN)-free antiviral therapy determines significant changes in glycometabolic control and clinical outcomes of diabetic patients. A beneficial effect of SVR obtained by DAA therapy on DM prevention and the short-term outcome of glycometabolic alterations are acknowledged by most of the studies. Whether this effect is maintained over the long term with a significant clinical impact on diabetic and liver disease is still a matter of debate.

Hepatitis C, systemic inflammation and oxidative stress: correlations with metabolic diseases

Introduction: Hepatitis C chronic infection has long been correlated with numerous systemic diseases, such as diabetes mellitus and hepatic steatosis. Recent studies have also revealed an association with atherosclerosis.Areas covered: An analysis is presented on the mechanisms through which the hepatitis C viral infection can lead to a systemic increase in pro-inflammatory markers, especially tumor necrosis factor-a and interleukin-6. The immunological imbalance created may, through different mechanisms, act on the metabolic pathways that contribute to the development of insulin resistance, the accumulation of lipids in the liver, and even the formation of atherosclerotic plaques. Moreover, an additional contributing factor to the above-mentioned metabolic derangements is the unopposed oxidative stress observed in chronic hepatitis C viral infection. The virus itself contributes to the formation of oxidative stress, through alterations in the trace metal homeostasis and its effect on pro-inflammatory cytokines, such as tumor necrosis factor-a.Expert opinion: The scope of this review is to emphasize the importance of the metabolic manifestations of hepatitis C viral infection and to elucidate the pathophysiological mechanisms behind their emergence.

Systematic review: chronic viral hepatitis and metabolic derangement

BACKGROUND

The liver has a critical role in the metabolism of glucose and lipids. Chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection leads to a spectrum of liver disease including chronic hepatitis, cirrhosis and hepatocellular carcinoma. Metabolic syndrome (MetS) has a rising incidence owing to an epidemic of type 2 diabetes mellitus (T2DM) and obesity. Non-alcoholic fatty liver disease is a liver manifestation of MetS and has become the most common cause of chronic liver disease worldwide.

AIM

To summarise the interplay among hepatitis viruses, MetS and its components.

METHODS

We searched the literature about HBV, HCV infection, MetS, fatty liver and its components from PubMed.

RESULTS

With respect to the viral replication cycle, lipids are important mediators between viral entry and hepatocyte in HCV infection, but not in HBV infection. Thus, HCV infection is inversely associated with hyperlipidaemia and lipid rebound occurs following sustained viral response induced by interferon-based therapy or direct antiviral agents. In addition, HCV infection is positively associated with insulin resistance, hepatic steatosis, MetS and the risk of T2DM and atherosclerosis. In contrast, HBV infection may protect infected subjects from the development of MetS and hepatic steatosis. Accumulating evidence suggests that HBV infection is inversely associated with lipid metabolism, and exhibits no conclusive association with insulin resistance or the risk of T2DM and arteriosclerosis.

CONCLUSIONS

In patients with viral hepatitis and concurrent metabolic diseases, a multidisciplinary approach should be given rather than simply antiviral treatment.

Serum cytokines, adipokines and ferritin for non-invasive assessment of liver fibrosis in chronic liver disease: a systematic review

Chronic liver disease (CLD) is a major health problem worldwide. Non-alcoholic fatty liver disease (NAFLD), chronic hepatitis C (CHC), chronic hepatitis B (CHB), and alcoholic liver disease (ALD) are the most common etiologies of CLD. Liver biopsy is the gold standard for assessment of liver fibrosis, however, it is an invasive method. This review attempts to evaluate the usefulness of serum adiponectin, serum leptin, serum ferritin, serum transforming growth factor-β1 (TGF-β1), and serum platelet derived growth factor-BB (PDGF-BB) as non-invasive markers in the diagnosis of liver fibrosis/cirrhosis. A systematic search in MEDLINE, Web of Science, Scopus, and local databases was performed to identify articles published in English or Persian as of November 2017. Studies conducted among CLD patients, with biopsy proven fibrosis/cirrhosis, and providing sufficient details of patients' clinicopathological characteristics were included. In the 95 studies included, there were a total of 15,548 CLD patients. More than 83% of studies were carried out in Asia and Europe. The relationship between liver fibrosis/cirrhosis and serum levels of ferritin, adiponectin, leptin, TGF-β1, and PDGF-BB was assessed in 42, 33, 27, nine, and three studies, respectively. Serum levels of the markers, particularly ferritin, could successfully predict liver fibrosis/cirrhosis, however, these data might not be clinically replicated and further studies are needed.

Liraglutide Inhibits Hepatitis C Virus Replication Through an AMP Activated Protein Kinase Dependent Mechanism

Insulin resistance and diabetes are both associated with chronic hepatitis C virus (HCV) infection, and the glucagon-like peptide-1(GLP-1) receptor agonist, liraglutide, is a common therapy for diabetes. Our aim was to investigate whether liraglutide treatment can inhibit HCV replication. A cell culture-produced HCV infectious system was generated by transfection of in vitro-transcribed genomic JFH-1 ribonucleic acid (RNA) into Huh-7.5 cells. Total RNA samples were extracted to determine the efficiency of HCV replication. The Ava5 cells were treated with liraglutide and cell viability was calculated. A Western blot analysis of the protein expression was performed. The immunoreactive blot signals were also detected. Liraglutide activated GLP-1 receptors in the HCV infectious system, and inhibited subgenomic HCV RNA replication in the HuH-7.5 cells. The Western blot analysis revealed both HCV protein and replicon RNA were reduced after treatment with liraglutide in a dose-dependent manner. Liraglutide decreased the cell viability of HCV RNA at an optimum concentration of 120 μg/mL, activated the 5′ adenosine monophosphate-activated protein kinase (AMPK) and the phosphorylated- transducer of regulated cyclic adenosine monophosphate (CAMP) response element-binding protein 2 (TORC2), thereby decreasing the cell viability of phosphoenolpyruvate carboxykinase (PEPCK) and G6pase RNA Therefore, we conclude that liraglutide can inhibit HCV replication via an AMPK/TORC2-dependent pathway.

Clinical outcomes in chronic hepatitis C long-term responders to pre-direct antiviral agents: a single-center retrospective study

BACKGROUND

Obesity, type 2 diabetes (T2D), dyslipidemia, arterial hypertension as well as hepatic steatosis (HS) are common conditions that can affect clinical outcomes of patients with chronic hepatitis C (CHC) who achieved sustained virologic response (SVR). The aim of this study was to assess the impact of metabolic cofactors on the occurrence of clinical events during follow-up (FU) in a group of CHC long-term responders (LTRs) to interferon- (IFN) based therapy.

METHODS

A total of 5172 medical records of CHC patients enrolled from 1990 to 2011 were examined; 1034 of 5172 (20%) patients were treated with IFN-based therapy and 382 of 1034 (37%) of them achieved SVR. A total of 188 (49%) LTRs underwent liver biopsy before antiviral treatment. Data on liver and cardiometabolic events such as cirrhosis and its complications, hepatocellular carcinoma, coronary artery disease, arterial hypertension, impaired fasting glucose (IFG)/type 2 diabetes (T2D) and dyslipidemia, were collected over time.

RESULTS

The mean age of the whole cohort was 46±12 years and 114/188 (61%) patients were males. HS was found in 82 of 188 (43.6%) patients and most of them were infected by HCV genotype 3a. The prevalence of obesity, IFG/T2D, dyslipidemia and arterial hypertension was 4.3%, 6.9%, 37.2%, and 5.9%, and was similarly distributed among patients with and without HS. Cirrhosis was histologically diagnosed in 18 of 188 (9.6%) patients. After a median follow-up of 11 years (range 3-21 years), the cumulative incidence of cardiovascular events, IFG/T2D and dyslipidemia was higher in CHC-LTRs who had HS at baseline compared to those without HS (1.2%, 2.3%, and 3.0% vs. 0.4%, 0.8%, and 2.5%, respectively). At multivariable Cox regression analysis, HS was significantly associated to the development of cardiovascular events and IFG/T2D (HR=5.2, 95% CI: 1.3-20.7, P=0.019, and HR=2.6, 95% CI: 1.1-6.2, P=0.027, respectively).

CONCLUSIONS

In CHC-LTRs, HS at baseline may predispose to the development of cardiovascular events and T2D during follow-up emphasizing the importance of an accurate counseling in order to prevent extra-hepatic complications.

Classic and Novel Adipocytokines at the Intersection of Obesity and Cancer: Diagnostic and Therapeutic Strategies

PURPOSE OF REVIEW

In this review, we investigate the role of classic and novel adipocytokines in cancer pathogenesis synopsizing the mechanisms underlying the association between adipocytokines and malignancy. Special emphasis is given on novel adipocytokines as new evidence is emerging regarding their entanglement in neoplastic development.

RECENT FINDINGS

Recent data have emphasized the role of the triad of overweight/obesity, insulin resistance and adipocytokines in cancer. In the setting of obesity, classic and novel adipocytokines present independent and joint effects on activation of major intracellular signaling pathways implicated in cell proliferation, expansion, survival, adhesion, invasion, and metastasis. Until now, more than 15 adipocytokines have been associated with cancer, and this list continues to expand. While the plethora of circulating pro-inflammatory adipocytokines, such as leptin, resistin, extracellular nicotinamide phosphoribosyl transferase, and chemerin are elevated in malignancies, some adipocytokines such as adiponectin and omentin-1 are generally decreased in cancers and are considered protective against carcinogenesis. Elucidating the intertwining of inflammation, cellular bioenergetics, and adiposopathy is significant for the development of preventive, diagnostic, and therapeutic strategies against cancer. Novel more effective and safe adipocytokine-centered therapeutic interventions may pave the way for targeted oncotherapy.

Chronic hepatitis C, atherosclerosis and cardiovascular disease: What impact of direct-acting antiviral treatments?

Hepatitis C virus (HCV) infection is associated with extrahepatic manifestations, among these there is an increased risk of atherosclerosis and cardiovascular disease as well as an increased cardiovascular mortality. Several direct and indirect HCV pro-atherogenic mechanisms have been proposed. HCV lives and replicates within carotid plaques, promoting a local environment of pro-atherogenic factors. In addition, it causes conditions such as insulin resistance, diabetes, hepatic steatosis, cryoglobulinemia and endotoxinemia that are associated with the development of atherosclerosis and cardiovascular disease. Therapeutic regimens based on direct-acting antiviral agents (DAA) are currently available with high efficacy in HCV clearance and improvement of liver disease, but does HCV eradication also improve atherosclerosis and the risk of cardiovascular disease? Recently, a multi-center study has shown that elimination of HCV improves carotid atherosclerosis. Two studies have shown that DAA treatments significantly reduce the risk of cardiovascular events. Several studies have assessed the impact of HCV clearance on pro-atherosclerosis metabolic conditions showing improvement in cardiovascular risk biomarkers, disappearance or improvement of insulin resistance, reduction of risk of developing diabetes and improvement of glycemic control. There are also evidences that HCV clearance promotes the recovery of cytokines and inflammatory markers associated with atherosclerosis and the disappearance of cryoglobulinemia. Available data show that clearance of HCV by DAAs is associated with an improvement in atherosclerosis and metabolic and immunological conditions that promote the development of cardiovascular disease. However, the data are not sufficient to allow definitive conclusions and further studies will be needed to definitively clarify the impact of HCV clearance on atherosclerosis and cardiovascular disease.

Endotoxinemia contributes to steatosis, insulin resistance and atherosclerosis in chronic hepatitis C: the role of pro-inflammatory cytokines and oxidative stress

PURPOSE

Endotoxin is a component of the outer membrane of gram-negative bacteria that live in the intestine. Endotoxinemia is reported in non-alcoholic fatty liver disease and in cirrhotic patients, causing various biological and clinical effects in the host. It is not known whether endotoxinemia occurs in chronic hepatitis C patients (CHC), therefore we evaluated the occurrence of endotoxinemia and its effect on inflammation, liver damage, insulin resistance (IR) and atherosclerosis.

METHODS

Consecutive CHC patients assessed by liver biopsy were enrolled. Endotoxinemia was evaluated by LAL test. IR was estimated by HOMA-IR. Serum TNF-α, IL-8, adiponectin and MCP-1 were measured with ELISA tests. Oxidative stress was estimated by circulating IgG against malondialdehyde adducts with human serum albumin (MDA-HAS). Carotid atherosclerosis was assessed by ultrasonography.

RESULTS

Endotoxinemia was found in 60% of the 126 patients enrolled. A serum level-dependent association between endotoxinemia, steatosis (p < 0.001) and HOMA-IR (p < 0.006) was observed. Patients with endotoxinemia showed significant increase in TNF-α and IL8 levels. TNF-α correlated with steatosis (p <  0.001) and HOMA-IR (p < 0.03), whereas IL8 correlated with steatosis (p =  <0.001), TNF-α (p < 0.04) and atherosclerosis (p < 0.01). The highest levels of endotoxinemia were associated with oxidative stress and a higher prevalence of carotid atherosclerosis. Multivariate logistic regression analysis showed that the independent factors associated with endotoxinemia were hepatic steatosis, HOMA-IR, IL8 and MDA-HAS.

CONCLUSIONS

Endotoxinemia occurs with high frequency in CHC patients and contributes to the development of hepatic steatosis, IR and atherosclerosis through increased pro-inflammatory cytokines and oxidative stress. Anti-endotoxin treatment could be of clinical relevance.

Hepatitis C virus eradication by direct-acting antiviral agents improves carotid atherosclerosis in patients with severe liver fibrosis

BACKGROUND AND AIMS

Recent studies suggest an association between hepatitis C virus (HCV) infection and cardiovascular damage, including carotid atherosclerosis, with a possible effect of HCV clearance on cardiovascular outcomes. We aimed to examine whether HCV eradication by direct-acting antiviral agents (DAA) improves carotid atherosclerosis in HCV-infected patients with advanced fibrosis/compensated cirrhosis.

MATERIALS AND METHODS

One hundred eighty-two consecutive patients with HCV and advanced fibrosis or compensated cirrhosis were evaluated. All patients underwent DAA-based antiviral therapy according to AISF/EASL guidelines. Intima-media thickness (IMT), carotid thickening (IMT ≥1 mm) and carotid plaques, defined as focal thickening of ≥1.5 mm at the level of the common carotid, were evaluated by ultrasonography (US) at baseline and 9-12 months after the end of therapy. Fifty-six percent of patients were male, mean age 63.1 ± 10.4 years, and 65.9% had compensated cirrhosis. One in five had diabetes, 14.3% were obese, 41.8% had arterial hypertension and 35.2% were smokers. At baseline, mean IMT was 0.94 ± 0.29 mm, 42.8% had IMT ≥1 mm, and 42.8% had carotid plaques.

RESULTS

All patients achieved a 12-week sustained virological response. IMT significantly decreased from baseline to follow-up (0.94 ± 0.29 mm vs. 0.81 ± 0.27, p <0.001). Consistently, a significant reduction in the prevalence of patients with carotid thickening from baseline to follow-up was observed (42.8% vs. 17%, p <0.001), while no changes were reported for carotid plaques (42.8% vs. 47.8%, p = 0.34). These results were confirmed in subgroups of patients stratified for cardiovascular risk factors and liver disease severity.

CONCLUSION

HCV eradication by DAA improves carotid atherosclerosis in patients with severe fibrosis with or without additional metabolic risk factors. The impact of this improvement in the atherosclerotic burden in terms of reduction of major cardiovascular outcomes is worth investigating in the long term.

LAY SUMMARY

Hepatitis C virus eradication by direct-acting antiviral agents improves carotid atherosclerosis in patients with advanced fibrosis/compensated cirrhosis. The improvement in intima-media thickness and carotid thickening was confirmed after stratification for severity of liver disease and cardiovascular risk factors. Hepatitis C virus eradication by direct-acting antiviral agents also lead to improvement in glucose homeostasis and increased cholesterol levels.

Hepatitis C virus clearance by direct-acting antiviral treatments and impact on insulin resistance in chronic hepatitis C patients

BACKGROUND AND AIM

Chronic hepatitis C virus (HCV), particularly genotype 1, is associated with insulin resistance (IR) and diabetes. This study evaluated the impact of HCV clearance by all-oral direct-acting antiviral treatments on IR and glycemic control.

METHODS

Included in this prospective case-control study were 133 consecutive HCV-genotype 1 patients with advance liver fibrosis (F3-F4) without type 2 diabetes. Sixty eight were treated with direct-acting antiviral and 65 were untreated. Liver fibrosis was assessed by transient elastography. Pre-treatment, end-treatment, and 3 months post-treatment withdrawal IR homeostasis was assessed by homeostatic model assessment (HOMA)-IR, HOMA-S, and HOMA-B.

RESULTS

At baseline, treated, and untreated patients showed similar liver fibrosis levels, HOMA-IR was 4.90 ± 4.62 and 4.64 ± 5.62, respectively. HOMA-IR correlated with HCV RNA levels. At the end of treatment, all patients cleared HCV RNA, regardless of liver fibrosis and body mass index, and a reduction in HOMA-IR at 2.42 ± 1.85 was showed (P < 0.001); in addition, increased insulin sensitivity, decreased insulin secretion, reduction of serum glucose, and insulin levels were observed. Data were confirmed 3 months after treatment withdrawal in the 65 patients who cleared HCV. No variation occurred in untreated patients. Overall, 76.5% of sustained virologic response patients showed IR improvements, of which 41.2% normalized IR. Improvement of IR was strictly associated with HCV clearance; however, patients with the highest levels of fibrosis remain associated with some degree of IR.

CONCLUSIONS

The data underline a role of HCV in development of IR and that viral eradication reverses IR and improves glycemic control and this could prevent IR-related clinical manifestations and complications.

Effects and mechanisms of caffeine to improve immunological and metabolic abnormalities in diet-induced obese rats

In obesity, there are no effective therapies for parallel immune and metabolic abnormalities, including systemic/tissue insulin-resistance/inflammation, adiposity and hepatic steatosis. Caffeine has anti-inflammation, antihepatic steatosis, and anti-insulin resistance effects. In this study, we evaluated the effects and molecular mechanisms of 6 wk of caffeine treatment (HFD-caf) on immunological and metabolic abnormalities of high-fat diet (HFD)-induced obese rats. Compared with HFD vehicle (HFD-V) rats, in HFD-caf rats the suppressed circulating immune cell inflammatory [TNFα, MCP-1, IL-6, intercellular adhesion molecule 1 (ICAM-1), and nitrite] profiles were accompanied by decreased liver, white adipose tissue (WAT), and muscle macrophages and their intracellular cytokine levels. Metabolically, the increase in metabolic rates reduced lipid accumulation in various tissues, resulting in reduced adiposity, lower fat mass, decreased body weight, amelioration of hepatic steatosis, and improved systemic/muscle insulin resistance. Further mechanistic approaches revealed an upregulation of tissue lipogenic [(SREBP1c, fatty acid synthase, acetyl-CoA carboxylase)/insulin-sensitizing (GLUT4 and p-IRS1)] markers in HFD-caf rats. Significantly, ex vivo experiments revealed that the cytokine release by the cocultured peripheral blood mononuclear cell (monocyte) and WAT (adipocyte), which are known to stimulate macrophage migration and hepatocyte lipogenesis, were lower in HFD-V groups than HFD-caf groups. Caffeine treatment simultaneously ameliorates immune and metabolic pathogenic signals present in tissue to normalize immunolgical and metabolic abnormalities found in HFD-induced obese rats.

Metabolic and Cardiovascular Complications in HIV/HCV-Co-infected Patients

PURPOSE OF REVIEW

Fifteen to thirty percent of HIV-infected persons in North America and Europe are co-infected with chronic hepatitis C (HCV). The latter is associated with a significant number of extra-hepatic metabolic complications that could compound HIV-associated increased cardiovascular risk. This article reviews the basic science and epidemiologic and clinical evidence for increased cardio-metabolic risk among HIV/HCV-co-infected patients and discusses potential underlying mechanisms. We will finally review the impact of control of HCV viremia on the cardio-metabolic morbidity and mortality of HIV/HCV-co-infected patients.

RECENT FINDINGS

HCV infection is associated with a number of immune-related complications such as cryoglobulinemia but also metabolic complications including dyslipidemias, hepatic steatosis, insulin resistance, diabetes, and chronic kidney disease. The incidence of these complications is higher among HIV-co-infected patients and might contribute to increased mortality. The potential mechanisms of increased cardiovascular risk among HIV/HCV-co-infected subjects include endothelial dysfunction, chronic inflammation and immune activation, the cardio-metabolic effects of HCV-induced hepatic steatosis and fibrosis or insulin resistance, and chronic kidney disease. However, epidemiologic studies show discordant findings as to whether HCV co-infection further increases the risk of atherosclerotic cardiovascular diseases (acute myocardial infarctions and strokes) among HIV-infected patients. Nonetheless, successful treatment of HCV is associated with significant improvements in cardio-metabolic risk factors including diabetes mellitus. HCV co-infection is associated with a higher incidence of metabolic complications-and likely increased risk of cardiovascular events-that might contribute to increased mortality in HIV. These appear to improve with successful HCV therapy.

Chronic Hepatitis C Virus Infection and Depression

Hepatitis C virus (HCV) infection is a systemic disease with hepatic and extrahepatic manifestations, including neuropsychiatric conditions. Depression is a frequent disorder, which has been reported in one-third of patients with HCV infection and has an estimated prevalence of 1.5 to 4.0 times higher than that observed in patients with chronic hepatitis B virus infection or the general population. HCV seems to play a direct and indirect role in the development of depression. Impaired quality of life and increasing health care costs have been reported for patients with HCV infection with depression. Treatment-induced HCV clearance has been associated with improvement of depression and quality of life.

Metabolic Manifestations of Hepatitis C Virus: Diabetes Mellitus, Dyslipidemia

Metabolic disorders are common in patients with chronic hepatitis C virus (HCV) infection. Epidemiologic and clinical data indicate an overprevalence of lipids abnormalite, steatosis, insuline resistance (IR) and diabetes mellitus in HCV patients, suggesting that HCV itself may interact with glucido-lipidic metabolism. HCV interacts with the host lipid metabolism by several mechanisms leading to hepatic steatosis and hypolipidemia which are reversible after viral eradication. Liver and peripheral IR are HCV genotype/viral load dependent and improved after viral eradication. This article examines examine the relationship between HCV, lipid abnormalities, steatosis, IR, and diabetes and the pathogenic mechanisms accounting for these events in HCV-infected patients.

Adipokines, insulin resistance, hepatic steatosis, and necroinflammation in patients with chronic viral hepatitis

Background: Hypoadiponectinemia and hyperleptinemia, and reductions in the ratio of adiponectin to leptin (A/L ratio) are associated with the development of hepatic necroinflammation in nonalcoholic fatty liver, but the association of the adipokines with hepatic steatosis in chronic viral hepatitis is unclear.

Objective: To investigate the relationship between serum A/L ratio, insulin resistance, degree of hepatic steatosis, and necroinflammation in patients with chronic viral hepatitis.

Methods: We measured serum adiponectin, leptin, and resistin levels, insulin resistance, and analyzed the association between liver histopathology and the level of the adipokines in 44 patients with chronic viral hepatitis before they started treatment.

Results: We found that insulin resistance, leptin, and resistin levels tended to increase in the group with a greater degree of hepatic steatosis and necroinflammation, but that the increase was not significant. The adiponectin/leptin ratio (A/L ratio) in a group with a low degree of hepatic steatosis was significantly higher than it was in the group with a high degree of hepatic steatosis (3.1 ± 3.1 vs 1.2 ± 0.8; P = 0.008). The A/L ratio in a group with low histological activity index (HAI) scores was significantly higher than in the group with high HAI scores (3.7 ± 3.4 vs 1.1 ± 1.1; P = 0.006). Abdominal obesity was the only variable that showed a significant association with the HAI score (P = 0.03).

Conclusion: The serum A/L ratio in patients with chronic viral hepatitis showed a significant inverse association with their degree of hepatic steatosis and necroinflammation.

Metabolic Dysregulation in Hepacivirus Infection of Common Marmosets (Callithrix jacchus)

Chronic hepatitis C has been associated with metabolic syndrome that includes insulin resistance, hepatic steatosis and obesity. These metabolic aberrations are risk factors for disease severity and treatment outcome in infected patients. Experimental infection of marmosets with GBV-B serves as a tangible, small animal model for human HCV infection, and while virology and pathology are well described, a full investigation of clinical disease and the metabolic milieu is lacking. In this study six marmosets were infected intravenously with GBV-B and changes in hematologic, serum biochemical and plasma metabolic measures were investigated over the duration of infection. Infected animals exhibited signs of lymphocytopenia, but platelet and RBC counts were generally stable or even increased. Although most animals showed a transient decline in blood glucose, infection resulted in several fold increases in plasma insulin, glucagon and glucagon-like peptide 1 (GLP-1). All infected animals experienced transient weight loss within the first 28 days of infection, but also became hypertriglyceridemic and had up to 10-fold increases in adipocytokines such as resistin and plasminogen activator inhibitor 1 (PAI-1). In liver, moderate to severe cytoplasmic changes associated with steatotic changes was observed microscopically at 168 days post infection. Collectively, these results suggest that GBV-B infection is accompanied by hematologic, biochemical and metabolic abnormalities that could lead to obesity, diabetes, thrombosis and atherosclerosis, even after virus has been cleared. Our findings mirror those found in HCV patients, suggesting that metabolic syndrome could be conserved among hepaciviruses, and both mechanistic and interventional studies for treating HCV-induced metabolic complications could be evaluated in this animal model.

Interrelationship between insulin resistance and portal haemodynamic abnormality in cirrhosis

Background: There are only limited data regarding the effect of impaired portal circulation on the glucose metabolism. The study prospectively examined the interrelationship between insulin resistance (IR) and portal haemodynamic abnormality in cirrhosis. Methods: There were 53 cirrhosis patients (61.6 ± 13.0 years) all presenting gastroesophageal varices. Portal haemodynamics by both hepatic venous catheterisation and Doppler ultrasound were examined with respect to the homeostasis model assessment (HOMA)-IR and HOMA2-IR. The IR was defined by HOMA-IR > 3.0 or HOMA2-IR > 2.0. Results: Forty-two patients (79.2%) had collateral vessels, 38 with left gastric vein, 12 with short/posterior gastric vein, 9 with splenorenal shunt, and 3 with inferior mesenteric vein. Multivariate analysis provided significant factors; wedged hepatic venous pressure (HR1.183, 95% CI 1.012-1.383, p=0.035) for HOMA-IR > 3.0, body mass index for HOMA2-IR > 2.0 (HR1.490, 95% CI 1.176-1.888, p=0.001), and collateral flow volume for both HOMA-IR > 3.0 (HR1.007, 95% CI 1.001-1.014, p=0.015) and HOMA2-IR > 2.0 (HR 1.007, 95% CI 1.002-1.013, p=0.009). The best cut-off value of collateral flow volume was 165 ml/min for detecting the HOMA-IR > 3.0 showing area under the receiver operating characteristic curve (AUROC) 0.688 (Odds ratio, 5.33) with sensitivity 70% and specificity 69.6%, and was 165 ml/min for detecting median value of HOMA2-IR > 2.0 showing AUROC 0.698 (odds ratio, 5.7) with sensitivity 75% and specificity 65.5%. Conclusion: There is a close linkage between the IR and impaired portal haemodynamics presented by the collateral development, suggesting the underlying pathogenesis of portal hypertension in cirrhosis patients.

Influence of insulin resistance on the development of hepatocellular carcinoma after antiviral treatment for non-cirrhotic patients with chronic hepatitis C

Background

Insulin resistance is considered to be an important factor in the progression of fibrosis and the enhancement of the risk of hepatocellular carcinoma (HCC) for chronic hepatitis C patients. The aim of this study was to assess the effect of insulin resistance on the development of HCC by non-cirrhotic chronic hepatitis C patients treated with pegylated interferon alpha-2b (PEG-IFNα2b) and ribavirin.

Methods

This retrospective study consisted of 474 Japanese non-cirrhotic patients with chronic hepatitis C. The cumulative incidence of HCC was estimated using the Kaplan-Meier method, according to insulin resistance by the homeostasis model assessment of insulin resistance (HOMA-IR) and treatment outcome.

Results

The overall sustained virological response (SVR) rate was 45.1 % (214/474, genotype 1: 35.4 % [129/364] and genotype 2: 77.3 % [85/110]). Twenty-one (4.4 %) patients developed HCC during the follow-up period. The 5-year cumulative incidence of HCC of the SVR group (2.6 %) was significantly lower than that of the non-SVR group (9.7 %) (log-rank test: P = 0.025). In multivariable logistic regression analysis, HOMA-IR (≥2.5) (hazard ratio [HR] 12.8, P = 0.0006), fibrosis status (F3) (HR 8.85, P < 0.0001), and post-treatment alanine aminotransferase (ALT) level (≥40 U/L) (HR 4.33, P = 0.036) were independently correlated to the development of HCC. Receiver operating characteristic analysis to determine the optimal threshold value of HOMA-IR for predicting the development of HCC in the non-SVR group showed that the areas under the curve was high (0.80, cutoff value: 3.0). Only three patients (1.4 %) who achieved SVR developed HCC. Two of them had severe insulin resistance and did not show improvement in HOMA-IR after achieving SVR.

Conclusions

Insulin resistance has a strong impact on the development of HCC by non-cirrhotic patients who have PEG-IFNα2b and ribavirin treatment failure.

Extrahepatic manifestations in chronic hepatitis C virus carriers

Patients with chronic hepatitis C virus (HCV) infection frequently present with extrahepatic manifestations covering a large spectrum, involving different organ systems leading to the concept of systemic HCV infection. These manifestations include autoimmune phenomena and frank autoimmune and/or rheumatic diseases and may dominate the course of chronic HCV infection. Chronic HCV infection causes liver inflammation affecting the development of hepatic diseases. HCV is also a lymphotropic virus that triggers B cells and promotes favorable conditions for B lymphocyte proliferation, including mixed cryoglobulinemia (MC) and MC vasculitis, which is the most prominent extrahepatic manifestation of chronic HCV infection. HCV may also promote a low-grade chronic systemic inflammation that may affect the development of some extrahepatic manifestations, particularly cardiovascular and cerebral vascular diseases. Recognition of extrahepatic symptoms of HCV infection could facilitate early diagnosis and treatment. The development of direct-acting antiviral agents (DDAs) has revolutionized HCV treatment. DDAs, as well as new B-cell-depleting or B-cell-modulating monoclonal antibodies, will expand the panorama of treatment options for HCV-related extrahepatic manifestations including cryoglobulinemic vasculitis. In this context, a proactive, integrated approach to HCV therapy should maximize the benefits of HCV therapy, even when liver disease is mild.

Adiponectin: A biomarker for chronic hepatitis C?

Adiponectin, a hormone primarily synthesized and secreted by adipose tissue, plays a pivotal role in lipid metabolism. Chronic hepatitis C (CHC) infection is characterized by disordered lipid metabolism, which may potentially evolve into steatosis over a period of time. A growing body of evidence appears to link decreased adiponectin plasma levels with severe CHC-related steatosis, which suggests a potential role of this adipokine as a diagnostic and therapeutic target for clinical application. In this review, we have attempted to summarize the current status of adiponectin research in the context of CHC, concentrating predominantly on its roles in CHC, and its potential relevance as a biomarker for CHC.

Association between IL28B polymorphism, TNFα and biomarkers of insulin resistance in chronic hepatitis C-related insulin resistance

TNFα has been shown to play a role in hepatitis C virus (HCV)-induced insulin resistance (IR). Polymorphism of the IL28B gene that encodes IFN-lambda 3 may be associated with IR through modulation of TNFα. The aim of this study was to investigate the relationship between IL28B rs12979860 genotype, the level of TNFα activation and the degree of IR in patients with chronic hepatitis C. One hundred and thirty-three nondiabetic genotype 1 HCV-infected patients with biopsy proven noncirrhotic hepatitis C were investigated for IR (using HOMA index), IL28B rs12979860 genotype and fasting circulating levels of soluble receptor 1 of TNFα (sTNFR1) and adipokines: leptin, adiponectin and IL-6. The HOMA-IR was positively correlated with serum levels of leptin (r = 0.35, P < 0.0001) and sTNFR1 (r = 0.35, P < 0.0001) but not with IL-6 or adiponectin. IL28B rs12979860 CC genotype was observed in 35% patients. Genotype CC and nongenotype CC patients were similar in terms of HOMA-IR (means 1.6 ± 0.9 vs 1.7 ± 1.4) and had similar circulating levels of sTNFR1 and adipokines. Independent factors associated with IR were ferritin (OR = 1.002, P = 0.02), leptin (OR = 1.06, P = 0.02) and sTNFR1 (OR = 7.9, P = 0.04). This study suggests that in nondiabetic, noncirrhotic, HCV genotype 1-infected patients, there is no relationship between IL28B rs12979860 genotype and HOMA-IR or sTNFR1 level. HCV-related IR may be mediated through TNFα independent of IL28B genotype.

Substitution in Amino Acid 70 of Hepatitis C Virus Core Protein Changes the Adipokine Profile via Toll-Like Receptor 2/4 Signaling

Background & Aims

It has been suggested that amino acid (aa) substitution at position 70 from arginine (70R) to glutamine (70Q) in the genotype 1b hepatitis C virus (HCV) core protein is associated with insulin resistance and worse prognosis. However, the precise mechanism is still unclear. The aim of this study was to investigate the impact of the substitution at position 70 in HCV core protein on adipokine production by murine and human adipocytes.

Methods

The influence of treatment with HCV core protein (70R or 70Q) on adipokine production by both 3T3-L1 and human adipocytes were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and triglyceride content was also analyzed. The effects of toll-like receptor (TLR)2/4 inhibition on IL-6 production by 3T3-L1 induced by HCV core protein were examined.

Results

IL-6 production was significantly increased and adiponectin production was reduced without a change in triglyceride content by treatment with 70Q compared to 70R core protein in both murine and human adipocytes. IL-6 induction of 3T3-L1 cells treated by 70Q HCV core protein was significantly inhibited with anti-TLR2 antibody by 42%, and by TLR4 inhibitor by 40%.

Conclusions

Our study suggests that extracellular HCV core protein with substitution at position 70 enhanced IL-6 production and reduced adiponectin production from visceral adipose tissue, which can cause insulin resistance, hepatic steatosis, and ultimately development of HCC.

Insulin resistance and its consequences in chronic hepatitis C

Chronic hepatitis C (CHC) is generally a slowly progressive disease, but some factors associated with rapid progression have been identified. Hepatitis C virus (HCV) may contribute to a broad spectrum of metabolic disturbances - namely, steatosis, insulin resistance (IR), increased prevalence of impaired glucose tolerance, type 2 diabetes mellitus (T2DM), lipid metabolism abnormalities and atherosclerosis. HCV can directly or indirectly cause both IR and steatosis, but it is still not resolved whether this viral impact bears the same prognostic value as the metabolic counterparts. As the population exposed to HCV ages, the morbidity due to this disease is increasing. The rising epidemic of obesity contributes to higher prevalence of IR and T2DM. Our understanding of the mutual association between both disease states continues to grow, but is still far from complete. This review briefly discusses the most probable mechanisms involved in IR development in the course of CHC. Molecular mechanisms for the direct and indirect influence of HCV on intracellular insulin signaling are described. Subsequently, the consequences of IR/T2DM for disease progression and management are summarized.

Adiponectin serum level in chronic hepatitis C infection and therapeutic profile

Hepatic steatosis is commonly seen in the patients with chronic hepatitis C virus (HCV) infection. HCV is closely associated with lipid metabolism, and viral steatosis is more common in genotype 3 infection owing to a direct cytopathic effect of HCV core protein. In non-genotype 3 infection, hepatic steatosis is considered largely to be the result of the alterations in host metabolism; metabolic steatosis is primarily linked with HCV genotype 1. Adipose tissue secretes different hormones involved in glucose and lipid metabolisms. It has been demonstrated that adipocytokines are involved in the pathogenesis of non-alcoholic fatty liver disease, as the decreased plasma adiponectin levels, a soluble matrix protein expressed by adipoctyes and hepatocyte, are associated with liver steatosis. Various studies have shown that steatosis is strongly correlated negatively with adiponectin in the patients with HCV infection. The role of adiponectin in hepatitis C virus induced steatosis is still not completely understood, but the relationship between adiponectin low levels and liver steatosis is probably due to the ability of adiponectin to protect hepatocytes from triglyceride accumulation by increasing β-oxidation of free fatty acid and thus decreasing de novo free fatty acid production.

Diabetes and Hepatitis C: A Two-Way Association

Diabetes and hepatitis C infection are both prevalent diseases worldwide, and are associated with increased morbidity and mortality. Most studies, but not all, have shown that patients with chronic hepatitis C are more prone to develop type 2 diabetes (T2D) compared to healthy controls, as well as when compared to patients with other liver diseases, including hepatitis B. Furthermore, epidemiological studies have revealed that patients with T2D may also be at higher risk for worse outcomes of their hepatitis C infection, including reduced rate of sustained virological response, progression to fibrosis and cirrhosis, and higher risk for development of hepatocellular carcinoma. Moreover, hepatitis C infection and mainly its treatment, interferon α, can trigger the development of type 1 diabetes. In this review, we discuss the existing data on this two-way association between diabetes and hepatitis C infection with emphasis on possible mechanisms. It remains to be determined whether the new curative therapies for chronic hepatitis C will improve outcomes in diabetic hepatitis C patients, and conversely whether treatment with Metformin will reduce complications from hepatitis C virus infection. We propose an algorithm for diabetes screening and follow-up in hepatitis C patients.

Recurrent HCV after liver transplantation-mechanisms, assessment and therapy

Chronic HCV infection is the leading indication for liver transplantation. However, as a result of HCV recurrence, patient and graft survival after liver transplantation are inferior compared with other indications for transplantation. HCV recurrence after liver transplantation is associated with considerable mortality and morbidity. The development of HCV-related fibrosis is accelerated after liver transplantation, which is influenced by a combination of factors related to the virus, donor, recipient, surgery and immunosuppression. Successful antiviral therapy is the only treatment that can attenuate fibrosis. The advent of direct-acting antiviral agents (DAAs) has changed the therapeutic landscape for the treatment of patients with HCV. DAAs have improved tolerability, and can potentially be used without PEG-IFN for a shorter time than previous therapies, which should result in better outcomes. In this Review, we describe the important risk factors that influence HCV recurrence after liver transplantation, highlighting the mechanisms of fibrosis and the integral role of hepatic stellate cells. Indirect and direct assessment of fibrosis, in addition to new antiviral therapies, are also discussed.

Chronic hepatitis C virus infection and atherosclerosis: Clinical impact and mechanisms

Hepatitis C virus (HCV) infection represents a major health issue worldwide due to its burden of chronic liver disease and extrahepatic manifestations including cardiovascular diseases, which are associated with excess mortality. Analysis of published studies supports the view that HCV infection should be considered a risk factor for the development of carotid atherosclerosis, heart failure and stroke. In contrast, findings from studies addressing coronary artery disease and HCV have yielded conflicting results. Therefore, meta-analytic reviews and prospective studies are warranted. The pathogenic mechanisms connecting HCV infection, chronic liver disease, and atherogenesis are not completely understood. However, it has been hypothesized that HCV may promote atherogenesis and its complications through several direct and indirect biological mechanisms involving HCV colonization and replication within arterial walls, liver steatosis and fibrosis, enhanced and imbalanced secretion of inflammatory cytokines, oxidative stress, endotoxemia, mixed cryoglobulinemia, perturbed cellular and humoral immunity, hyperhomocysteinemia, hypo-adiponectinaemia, insulin resistance, type 2 diabetes and other components of the metabolic syndrome. Understanding these complex mechanisms is of fundamental importance for the development of novel therapeutic approaches to prevent and to treat vascular complications in patients with chronic HCV infection. Currently, it seems that HCV clearance by interferon and ribavirin treatment significantly reduces non-liver-related mortality; moreover, interferon-based treatment appears to decrease the risk of ischemic stroke.

Hepatitis C and lipid metabolism, hepatic steatosis, and NAFLD: still important in the era of direct acting antiviral therapy?

Chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) have an individual prevalence of 1.8-3% and at least 30%, respectively, in the United States. It is therefore not surprising that there is overlap between these two common chronic liver diseases, although the relationship appears to go beyond isolated co-existence. Hepatic steatosis is a common feature of CHC infection and can be related to both metabolic and viral specific factors. Steatosis in the setting of nongenotype 3 CHC has been predictive of response to therapy prior to the advent of the direct acting antiviral medications (DAAs). Similarly, lipid metabolism appears important in response to CHC treatment. The pathways for both lipid homeostasis and NAFLD as it pertains to CHC infection as well as the utilization of statin therapy in CHC infection will be reviewed with a focus on the relevance of these topics in the era of DAA therapy.

Helicobacter pylori infection does not promote hepatocellular cancer in a transgenic mouse model of hepatitis C virus pathogenesis

Helicobacter pylori (H. pylori) and hepatitis C virus (HCV) infect millions of people and can induce cancer. We investigated if H. pylori infection promoted HCV-associated liver cancer. Helicobacter-free C3B6F1 wild-type (WT) and C3B6F1-Tg(Alb1-HCVN)35Sml (HT) male and female mice were orally inoculated with H. pylori SS1 or sterile media. Mice were euthanized at ~12 mo postinoculation and samples were collected for analyses. There were no significant differences in hepatocellular tumor promotion between WT and HT mice; however, HT female mice developed significantly larger livers with more hepatic steatosis than WT female mice. H. pylori did not colonize the liver nor promote hepatocellular tumors in WT or HT mice. In the stomach, H. pylori induced more corpus lesions in WT and HT female mice than in WT and HT male mice, respectively. The increased corpus pathology in WT and HT female mice was associated with decreased gastric H. pylori colonization, increased gastric and hepatic interferon gamma expression, and increased serum Th1 immune responses against H. pylori. HT male mice appeared to be protected from H. pylori-induced corpus lesions. Furthermore, during gastric H. pylori infection, HT male mice were protected from gastric antral lesions and hepatic steatosis relative to WT male mice and these effects were associated with increased serum TNF-α. Our findings indicate that H. pylori is a gastric pathogen that does not promote hepatocellular cancer and suggest that the HCV transgene is associated with amelioration of specific liver and gastric lesions observed during concurrent H. pylori infection in mice.

Chronic HCV infection and inflammation: Clinical impact on hepatic and extra-hepatic manifestations

The liver has a central role in regulating inflammation by its capacity to secrete a number of proteins that control both local and systemic inflammatory responses. Chronic inflammation or an exaggerated inflammatory response can produce detrimental effects on target organs. Chronic hepatitis C virus (HCV) infection causes liver inflammation by complex and not yet well-understood molecular pathways, including direct viral effects and indirect mechanisms involving cytokine pathways, oxidative stress and steatosis induction. An increasing body of evidence recognizes the inflammatory response in chronic hepatitis C as pathogenically linked to the development of both liver-limited injury (fibrosis, cirrhosis and hepatocellular carcinoma) and extrahepatic HCV-related diseases (lymphoproliferative disease, atherosclerosis, cardiovascular and brain disease). Defining the complex mechanisms of HCV-induced inflammation could be crucial to determine the global impact of infection, to estimate progression of the disease, and to explore novel therapeutic approaches to avert HCV-related diseases. This review focuses on HCV-related clinical conditions as a result of chronic liver and systemic inflammatory states.

Chronic HCV infection is a risk factor of ischemic stroke

OBJECTIVES

Cerebrovascular diseases are leading cause of death worldwide. Plaque rupture and embolization account for one-third of ischemic stroke. The causes are not fully known, but inflammation plays a pathogenic role. Recently, HCV infection has been identify as risk of atherosclerosis. HCV replicates within carotid plaques and brain endothelia cells; moreover, HCV patients showed higher levels of inflammation. Thus, we hypothesized that subjects carrying HCV are at higher risk of stroke. Accordingly, we evaluated prevalence and role of HCV infection in patients with stroke.

METHODS

A priori sample size was calculated. Overall, 820 consecutive patients were enrolled, 123 with stroke and, as control, 697 age- and gender-matched (295 with COPD; 402 with diseases other than HCV-associated). Patients were evaluated for HCV and conventional risk of stroke.

RESULTS

Prevalence of HCV was higher in patients with stroke than that observed in control (26.8% vs. 6.6%, p = 0.0001). An analysis of stroke patients showed that those HCV positive were younger (p = 0.017) had lower serum levels of cholesterol (p = 0.001), triglycerides (p = 0.045), and higher serum levels of inflammation markers (ESR, p = 0.001; CRP, p = 0.0001; fibrinogen, p = 0.012). A multivariate analysis showed that HCV infection was an independent risk factor of stroke (O.R. 2.04, 95% C.I. 1.69-2.46; p = 0.0001). A secondary analysis showed that HCV patients had higher (p = 0.031) prevalence of past ischemic heart disease.

CONCLUSIONS

HCV infected patients are at higher and earlier risk of stroke. Inflammation is a key mediator. Clinicians in clinical practice and researchers in future trials should take into account these new findings.

Nonalcoholic fatty liver disease following liver transplantation

Post-transplant, nonalcoholic hepatic steatosis and steatohepatitis are increasingly recognized as a complication of liver transplantation, and the progression of the latter through fibrosis to cirrhosis has been clearly shown. Non-alcoholic steatohepatitis (NASH) is independently associated with an increased risk of death from cardiovascular and liver diseases. While optimal therapy is not yet available in the post-liver transplant setting, knowledge gained in the therapy of NASH in the non-transplant setting can be used to design therapeutic interventions. In addition, early recognition with protocol liver biopsies and an effective preventive strategy by modifying known risk factors implicated in the recurrence of NASH would be the most effective way to curtail the progression of NASH before an effective treatment can be found. Additional rigorous research aimed at elucidating the pathogenesis, natural history, and selection of immunosuppressants for NASH is clearly warranted.

The predictive value of steatosis in hepatitis C virus infection

Steatosis is a complication of hepatitis C virus (HCV) infection and the mechanisms of its development are complex, involving viral and host factors. Steatosis that is prevalently viral is associated with HCV genotype 3, and steatosis that is prevalently metabolic is associated with non-3 genotypes. Viral steatosis is correlated with the level of HCV replication, whereas metabolic steatosis is related to insulin resistance. The two types of steatosis have a different impact on HCV disease and may have an additive effect. HCV infection is a multifaceted disease with hepatic and extrahepatic manifestations. There is a body of evidence indicating that HCV-related steatosis plays a role in many HCV manifestations and, thus, the presence of steatosis is a predictive factor for the development of such events. The current data show that HCV-related steatosis predicts an advanced liver disease and a more rapid progression of fibrosis, as well as an increased risk of development of hepatocellular carcinoma. Moreover, the presence of steatosis in a HCV patient has a high predictive value that the subject may have or may develop insulin resistance, diabetes and metabolic syndrome. Recently, a strict association between HCV-related steatosis and development of atherosclerosis has been demonstrated. In addition, steatosis negatively impacts response rate to interferon-based treatment, even in HCV genotype-3 infection. Therapeutic strategies to improve steatosis and, consequently, response to standard antiviral therapy and outcome of disease are wanted. The authors summarize current knowledge of impact of steatosis on the above reported clinical conditions associated with HCV infection.

The role of adiponectin in cancer: a review of current evidence

Excess body weight is associated not only with an increased risk of type 2 diabetes and cardiovascular disease (CVD) but also with various types of malignancies. Adiponectin, the most abundant protein secreted by adipose tissue, exhibits insulin-sensitizing, antiinflammatory, antiatherogenic, proapoptotic, and antiproliferative properties. Circulating adiponectin levels, which are determined predominantly by genetic factors, diet, physical activity, and abdominal adiposity, are decreased in patients with diabetes, CVD, and several obesity-associated cancers. Also, adiponectin levels are inversely associated with the risk of developing diabetes, CVD, and several malignancies later in life. Many cancer cell lines express adiponectin receptors, and adiponectin in vitro limits cell proliferation and induces apoptosis. Recent in vitro studies demonstrate the antiangiogenic and tumor growth-limiting properties of adiponectin. Studies in both animals and humans have investigated adiponectin and adiponectin receptor regulation and expression in several cancers. Current evidence supports a role of adiponectin as a novel risk factor and potential diagnostic and prognostic biomarker in cancer. In addition, either adiponectin per se or medications that increase adiponectin levels or up-regulate signaling pathways downstream of adiponectin may prove to be useful anticancer agents. This review presents the role of adiponectin in carcinogenesis and cancer progression and examines the pathophysiological mechanisms that underlie the association between adiponectin and malignancy in the context of a dysfunctional adipose tissue in obesity. Understanding of these mechanisms may be important for the development of preventive and therapeutic strategies against obesity-associated malignancies.

Chronic HCV infection is a risk of atherosclerosis. Role of HCV and HCV-related steatosis

OBJECTIVES

HCV and NAFLD are associated with atherosclerosis in general population. The prevalence of atherosclerosis in chronic hepatitis C (CHC) patients is unknown. We hypothesized that HCV per se and HCV-related steatosis could favour atherosclerosis. Thus, in CHC patients we assessed: (a) the prevalence of atherosclerosis; (b) the role of HCV, cardio-metabolic risk factors and hepatic histology.

METHODS

Overall, 803 subjects were enrolled: (A) 326 patients with liver biopsy-proven treatment naive CHC (175 with and 151 without steatosis); (B) 477 age and gender matched controls, including 292 healthy subjects without steatosis (B1) and 185 with NAFLD (B2). Carotid atherosclerosis (CA), assessed by high-resolution B-mode ultrasonography, was categorized as either intima-media thickness (IMT: >1mm) or plaques (≥ 1.5mm).

RESULTS

CHC patients had a higher prevalence of CA than controls (53.7% vs 34.3%; p<0.0001). Younger CHC (<50 years) had a higher prevalence of CA than controls (34.0% vs 16.0%; p<0.04). CHC patients without steatosis had a higher prevalence of CA than B1 controls (26.0% vs 14.8%; p<0.02). CHC with steatosis had a higher prevalence of CA than NAFLD patients (77.7% vs 57.8%, p<0.0001). Viral load was associated with serum CRP and fibrinogen levels; steatosis with metabolic syndrome, HOMA-IR, hyperhomocysteinemia and liver fibrosis. Viral load and steatosis were independently associated with CA. Diabetes and metabolic syndrome were associated with plaques.

CONCLUSION

HCV infection is a risk factor for earlier and facilitated occurrence of CA via viral load and steatosis which modulate atherogenic factors such as inflammation and dysmetabolic milieu.

HOMA-AD in Assessing Insulin Resistance in Lean Noncirrhotic HCV Outpatients

Introduction. There is an association between HCV and insulin resistance (IR), which is currently assessed by HOMA-IR. There is evidence that HOMA-adiponectin (HOMA-AD) is more accurate, but its role in HCV patients is unknown. The purpose of this study was to evaluate IR in an HCV sample and controls, in order to compare the accuracy of HOMA-IR and HOMA-AD. Methods. Ninety-four HCV outpatients aged <60 years who met the criteria of nondiabetic, nonobese, noncirrhotic, and nonalcohol abusers were included and compared to 29 controls. Fasting glucose, insulin, adiponectin, and lipid profiles were determined. IR was estimated by HOMA-IR and HOMA-AD. Results. The groups were similar regarding sex and BMI, but the HCV patients were older. The median insulin level was higher in the HCV group (8.6 mU/mL (6.5-13.7) versus 6.5 (4.3-10.7), P = 0.004), as was median HOMA-IR (1.94 (1.51 to 3.48) versus 1.40 (1.02 to 2.36), P = 0.002) and the prevalence of IR (38.3% versus 10.3% (P = 0.009)). No differences were found in adiponectin levels (P = 0.294) and HOMA-AD (P = 0.393). Conclusion. IR is highly prevalent even in low-risk HCV outpatients. Adiponectin is not influenced by the presence of HCV. HOMA-AD does not seem to be useful in assessing IR in HCV patients.

Nonalcoholic Fatty liver disease in chronic hepatitis B and C patients from Western Amazon

Nonalcoholic fatty liver disease (NAFLD) includes a wide spectrum of histological conditions, extending from simple steatosis to end-stage liver failure. The aim of this study was to examine the prevalence of NAFLD and its associations in chronic hepatitis B and C patients. Methods. We included all patients diagnosed with chronic hepatitis B and C who underwent a liver biopsy between January 2010 and October 2011 (n = 104). Parameters studied included hepatitis type, anthropometric data, histologic, hepatic, metabolic and lipid assessments, presence of hypertension and viral load. Results. Hepatitis B was presented in 28.8% (n = 30) of patients, while hepatitis C was presented in 71.2% (n = 74). In addition, hepatic steatosis was present in 25% (n = 26) of the patients. Steatosis was frequently found in hepatitis C patients (31.1%; 25% n = 23), but infrequently in hepatitis B patients (10%; n = 3) (P = 0.024). It was also found that steatosis was frequently present in hepatitis C patients with intense fibrosis (52.94%) (P = 0.025). Discussion. Our results suggest that steatosis is a common feature in patients with viral chronic hepatitis, and that it plays a different role in each type of hepatitis.

Adiponectin attenuates lipopolysaccharide-induced acute lung injury through suppression of endothelial cell activation

Adiponectin (APN) is an adipose tissue-derived factor with anti-inflammatory and vascular protective properties whose levels paradoxically decrease with increasing body fat. In this study, APN's role in the early development of ALI to LPS was investigated. Intratracheal LPS elicited an exaggerated systemic inflammatory response in APN-deficient (APN(-/-)) mice compared with wild-type (wt) littermates. Increased lung injury and inflammation were observed in APN(-/-) mice as early as 4 h after delivery of LPS. Targeted gene expression profiling performed on immune and endothelial cells isolated from lung digests 4 h after LPS administration showed increased proinflammatory gene expression (e.g., IL-6) only in endothelial cells of APN(-/-) mice when compared with wt mice. Direct effects on lung endothelium were demonstrated by APN's ability to inhibit LPS-induced IL-6 production in primary human endothelial cells in culture. Furthermore, T-cadherin-deficient mice that have significantly reduced lung airspace APN but high serum APN levels had pulmonary inflammatory responses after intratracheal LPS that were similar to those of wt mice. These findings indicate the importance of serum APN in modulating LPS-induced ALI and suggest that conditions leading to hypoadiponectinemia (e.g., obesity) predispose to development of ALI through exaggerated inflammatory response in pulmonary vascular endothelium.