Chemerin, vaspin and insulin resistance in chronic hepatitis C

Circulating Chemerin and Its Kinetics May Be a Useful Diagnostic and Prognostic Biomarker in Critically Ill Patients with Sepsis: A Prospective Study

Chemerin, a novel adipokine, is a potent chemoattractant molecule with antimicrobial properties, implicated in immune responses. Our aim was to investigate circulating chemerin and its kinetics, early in sepsis in critically ill patients and its association with severity and prognosis. Serum chemerin was determined in a cohort of 102 critically ill patients with sepsis during the first 48 h from sepsis onset and one week later, and in 102 age- and gender-matched healthy controls. Patients were followed for 28 days and their outcomes were recorded. Circulating chemerin was significantly higher in septic patients at onset compared to controls (342.3 ± 108.1 vs. 200.8 ± 40.1 μg/L, p < 0.001). Chemerin decreased significantly from sepsis onset to one week later (342.3 ± 108.1 vs. 308.2 ± 108.5 μg/L, p < 0.001), but remained higher than in controls. Chemerin was higher in patients presenting with septic shock than those with sepsis (sepsis onset: 403.2 ± 89.9 vs. 299.7 ± 99.5 μg/L, p < 0.001; one week after: 374.9 ± 95.3 vs. 261.6 ± 91.9 μg/L, p < 0.001), and in nonsurvivors than survivors (sepsis onset: 427.2 ± 96.7 vs. 306.9 ± 92.1 μg/L, p < 0.001; one week after: 414.1 ± 94.5 vs. 264.2 ± 79.9 μg/L, p < 0.001). Moreover, patients with septic shock and nonsurvivors, presented a significantly lower absolute and relative decrease in chemerin one week after sepsis onset compared to baseline (p < 0.001). Based on ROC curve analyses, the diagnostic performance of chemerin (AUC 0.78, 95% CI 0.69–0.87) was similar to C-reactive protein (CRP) (AUC 0.78, 95% CI 0.68–0.87) in discriminating sepsis severity. However, increased chemerin at sepsis onset and one week later was an independent predictor of 28-day mortality (sepsis onset: HR 3.58, 95% CI 1.48–8.65, p = 0.005; one week after: HR 10.01, 95% CI 4.32–23.20, p < 0.001). Finally, serum chemerin exhibited significant correlations with the severity scores, white blood cells, lactate, CRP and procalcitonin, as well as with biomarkers of glucose homeostasis, but not with cytokines and soluble urokinase-type plasminogen activator receptor (suPAR). Circulating chemerin is increased early in sepsis and its kinetics may have diagnostic and prognostic value in critically ill patients. Further studies are needed to shed light on the role of chemerin in sepsis.

HCV Genotype Has No Influence on the Incidence of Diabetes-EpiTer Multicentre Study

HCV infection is one of the main reasons for liver cirrhosis and hepatocellular carcinoma. In recent years, one finds more and more extrahepatic manifestations of HCV infection, including its possible influence on the development of diabetes. In the presented work, one finds the frequency analysis of the incidence of diabetes among 2898 HCV infected patients treated in Poland, and the assessment of their relevance to the HCV genotype and the progression of fibrosis. The results indicate that the hepatitis C infection seems to be a risk factor for diabetes in persons with more advanced liver fibrosis, for older people, and for the male gender. Thus, one found no differences regarding the frequency of its incidence depending on HCV genotype, including genotype 3.

Anti-inflammatory adipokines: chemerin, vaspin, omentin concentrations and SARS-CoV-2 outcomes

Coronavirus disease 2019 (COVID-19) is associated with systemic inflammation. A wide range of adipokines activities suggests they influence pathogenesis and infection course. The aim was to assess concentrations of chemerin, omentin, and vaspin among COVID-19 patients with an emphasis on adipokines relationship with COVID-19 severity, concomitant metabolic abnormalities and liver dysfunction. Serum chemerin, omentin and vaspin concentrations were measured in serum collected from 70 COVID-19 patients at the moment of admission to hospital, before any treatment was applied and 20 healthy controls. Serum chemerin and omentin concentrations were significantly decreased in COVID-19 patients compared to healthy volunteers (271.0 vs. 373.0 ng/ml; p < 0.001 and 482.1 vs. 814.3 ng/ml; p = 0.01, respectively). There were no correlations of analyzed adipokines with COVID-19 severity based on the presence of pneumonia, dyspnea, or necessity of Intensive Care Unit hospitalization (ICU). Liver test abnormalities did not influence adipokines levels. Elevated GGT activity was associated with ICU admission, presence of pneumonia and elevated concentrations of CRP, ferritin and interleukin 6. Chemerin and omentin depletion in COVID-19 patients suggests that this adipokines deficiency play influential role in disease pathogenesis. However, there was no relationship between lower adipokines level and frequency of COVID-19 symptoms as well as disease severity. The only predictive factor which could predispose to a more severe COVID-19 course, including the presence of pneumonia and ICU hospitalization, was GGT activity.

Chemerin Is a Valuable Biomarker in Patients with HCV Infection and Correlates with Liver Injury

Hepatitis C virus (HCV)-induced inflammation contributes to progressive liver disease. The chemoattractant protein chemerin is associated with systemic inflammation. We hypothesized that chemerin is a biomarker that predicts the severity of liver disease in HCV patients. Furthermore, we investigated whether serum chemerin levels change during the course of HCV treatment using direct-acting antivirals (DAAs). Therefore, we measured serum concentration of chemerin in a cohort of 82 HCV-infected patients undergoing DAA treatment. Serum chemerin was positively associated with leukocyte count and negatively with markers of hepatic function and the model of end-stage liver disease (MELD) score. Low circulating chemerin levels significantly correlated with advanced liver fibrosis and cirrhosis as measured by the fibrosis-4 (FIB-4) score, the aminotransferase/platelet (AST/PLT) ratio index (APRI) score and the non-alcoholic fatty liver disease (NAFLD) score. Chemerin did not correlate with viral load or viral genotype. Treatment with DAAs did not improve MELD score and leukocyte count within the observation period, up to three months after the end of DAA treatment. Accordingly, chemerin levels remained unchanged during the treatment period. We conclude that low circulating chemerin is a noninvasive biomarker for hepatic dysfunction and advanced liver fibrosis and cirrhosis in HCV infection.

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.

Chemerin Added to Endothelin-1 Promotes Rat Pulmonary Artery Smooth Muscle Cell Proliferation and Migration

Background

While chemerin has been shown to increase proliferation and migration of systemic vascular smooth muscle cells (SMCs) contributing therefore to the development of hypertension, this remains to be clarified for the pulmonary circulation.

Methods

Expression of chemerin and its three receptors (CMKRL1, CCRL2, GPR1) was examined by immunohistochemistry and RTq-PCR in lungs, pulmonary artery, and thoracic aorta from Wistar rats. Primary cultured rat pulmonary artery and thoracic aorta SMCs treated with recombinant chemerin (tested from 5.10^–9 to 10^–7 mol/L) were assessed for proliferation and migration (both with 10^–7 mol/L endothelin-1), as well as for staurosporine-induced apoptosis.

Results

In pulmonary artery and thoracic aorta, CMKLR1 expression was detected in both endothelial cells and SMCs. In primary cultured pulmonary artery SMCs, chemerin and its three receptors were expressed, and CMKLR1 expression was higher than those of CCRL2 and GPR1. Chemerin added to endothelin-1 increased pulmonary artery SMC proliferation, while chemerin or endothelin-1 alone did not. This effect was less pronounced in thoracic aorta SMCs. Chemerin induced pulmonary artery and thoracic aorta SMC migration, which was exacerbated by endothelin-1 and more pronounced in thoracic aorta SMCs. Chemerin concentration-dependently reduced staurosporine-induced apoptosis in both pulmonary artery and thoracic aorta SMCs. In pulmonary artery SMCs, endothelin-1 treatment increased the expression of CMKLR1, CCRL2, and GPR1, while these expressions were not altered in thoracic aorta SMCs.

Conclusion

Chemerin/CMKRL1 signaling, in conjunction with a key mediator in the pathogenesis of pulmonary hypertensive diseases, endothelin-1, stimulated proliferation and migration, and increased resistance to apoptosis in rat primary cultured pulmonary artery SMCs. Our results suggest that this signaling could play a role in pulmonary artery remodeling observed in pulmonary hypertension.

Serum visfatin and vaspin levels in hepatocellular carcinoma (HCC)

Hepatocellular carcinoma (HCC) is the most common liver cancer, accountable for 90% cases. Visfatin and vaspin are adipocytokines with various suggested functions and proven significant correlations between BMI and percentage of body fat. The aim was to assess visfatin and vaspin serum levels in HCC patients and controls, compare their levels in patients with different cancer etiology and grade assessed according to the Barcelona-Clinic Liver Cancer (BCLC) staging system. The additional aim was to analyze relationship between analyzed adipokines and metabolic abnormalities and liver disfunction severity. The study was performed on 69 cirrhotic patients (54 males/15 females) with HCC, aged 59.0 ± 12.1 years, and with BMI 29.0 ± 4.5 kg/m² compared to 20 healthy volunteers. Serum visfatin and vaspin concentrations were significantly increased in HCC patients compared to controls (p = 0.01 and p = 0.02, respectively). Serum vaspin was significantly higher in HCC patients with viral compared to those with non-viral etiology (p = 0.02), with more evident increase in chronic hepatitis C patients (CHC). Serum visfatin levels were significantly higher in patients with higher insulin resistance (p = 0.04) and with platelets count > 100 000/mm³ (p<0.001). Patients with BMI >30 kg/m² had markedly up-regulated vaspin levels (p = 0.04). There was no difference in vaspin and visfatin serum levels with respect to liver dysfunction and BCLC classification. In conclusion, our study revealed serum vaspin and visfatin to be significantly increased in HCC patients independently of cancer etiology compared to controls. Additionally, serum vaspin was elevated in viral disease, especially in CHC. Vaspin up-regulation can be a compensatory mechanism against IR in HCC patients. Serum visfatin and vaspin, although up-regulated, seem not to be associated with cancer grade and cirrhosis severity.

The adipokine vaspin reduces apoptosis in human hepatocellular carcinoma (Hep-3B) cells, associated with lower levels of NO and superoxide anion

BACKGROUND

Among adipose-derived factors, adipocytokines play roles as hormones and signaling mediators for apoptotic pathway. Among of them, vaspin, regulates the metabolism of adipose tissue itself as an endocrine organ, and stimulates adipocytes to maturation, differentiation, etc. Damaged adipocytes, present in obesity and hepatocellular carcinoma (HCC) respond with over-production of inflammatory cytokines. Such pro-inflammatory stimulation remains under adipokine control. Pro-inflammatory pathways are connected to oxidative stress and apoptosis, reported as co-existing with an elevated level of some adipokines in cancer cell lines. However, some hormones, such as vaspin, reduce apoptosis, have anti-inflammatory and anti-oxidative roles in cancer cell lines.

METHODS

Hep-3B cells were cytometrically evaluated under vaspin treatment for reactive oxygen species (ROS) and apoptosiss induction. The statistical significant changes to the untreated controls was calculated by T-tests (indicated at value p < 0.05).

RESULTS

Here we studied the production of reactive oxygen and nitrogen species in cells of HCC line Hep-3B after vaspin treatment. A decreased level of nitric oxide and superoxide anion 24 h after vaspin addition at 5 ng/ml was correlated with restricted, to the physiological level, apoptosis. A protective role of vaspin was displayed as enhanced cell viability and proliferation, which could be a poor prognostic in liver cancer.

CONCLUSIONS

Apoptosis was suppressed after vaspin treatment, together with low levels of nitric oxide and superoxide anions.

Serum Chemerin Does Not Differentiate Colorectal Liver Metastases from Hepatocellular Carcinoma

The chemoattractant adipokine chemerin is related to the metabolic syndrome, which is a risk factor for different cancers. Recent studies provide evidence that chemerin is an important molecule in colorectal cancer (CRC) and hepatocellular carcinoma (HCC). Serum chemerin is high in CRC patients and low in HCC patients and may serve as a differential diagnostic marker for HCC and liver metastases from CRC. To this end, serum chemerin was measured in 36 patients with CRC metastases, 32 patients with HCC and 49 non-tumor patients by ELISA. Chemerin serum protein levels were, however, similar in the three cohorts. Serum chemerin was higher in hypertensive than normotensive tumor patients but not controls. Cancer patients with hypercholesterolemia or hyperuricemia also had increased serum chemerin. When patients with these comorbidities were excluded from the calculation, chemerin was higher in CRC than HCC patients but did not differ from controls. Chemerin did not correlate with the tumor markers carcinoembryonic antigen, carbohydrate antigen 19-9 and alpha-fetoprotein in both cohorts and was not changed with tumor-node-metastasis stage in HCC. Chemerin was not associated with hepatic fat, liver inflammation and fibrosis. To conclude, systemic chemerin did not discriminate between CRC metastases and HCC. Comorbidities among tumor patients were linked with elevated systemic chemerin.

Treatment with direct-acting antivirals improves peripheral insulin sensitivity in non-diabetic, lean chronic hepatitis C patients

BACKGROUND AND AIMS

Hepatitis C virus (HCV) infection is associated with insulin resistance, which may lead to type 2 diabetes and its complications. Although HCV infects mainly hepatocytes, it may impair insulin sensitivity at the level of uninfected extrahepatic tissues (muscles and adipose tissue). The aim of this study was to assess whether an interferon-free, antiviral therapy may improve HCV-associated hepatic vs. peripheral insulin sensitivity.

METHODS

In a single-arm exploratory trial, 17 non-diabetic, lean chronic hepatitis C patients without significant fibrosis were enrolled, and 12 completed the study. Patients were treated with a combination of sofosbuvir/ledipasvir and ribavirin for 12 weeks, and were submitted to a 2-step euglycemic hyperinsulinemic clamp with tracers, together with indirect calorimetry measurement, to measure insulin sensitivity before and after 6 weeks of antivirals. A panel of 27 metabolically active cytokines was analyzed at baseline and after therapy-induced viral suppression.

RESULTS

Clamp analysis performed in 12 patients who achieved complete viral suppression after 6 weeks of therapy showed a significant improvement of the peripheral insulin sensitivity (13.1% [4.6-36.7], p = 0.003), whereas no difference was observed neither in the endogenous glucose production, in lipolysis suppression nor in substrate oxidation. A distinct subset of hepatokines, potentially involved in liver-to-periphery crosstalk, was modified by the antiviral therapy.

CONCLUSION

Pharmacological inhibition of HCV improves peripheral (but not hepatic) insulin sensitivity in non-diabetic, lean individuals with chronic hepatitis C without significant fibrosis.

Are Vaspin and Omentin-1 Related to Insulin Resistance, Blood Pressure and Inflammation in NAFLD Patients?

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of insulin resistance, is the most common cause of chronic liver. The present study aimed to investigate the roles of vaspin and omentin-1 in the NAFLD-related pathology including IR, inflammation and elevated blood pressure.

METHODS

This cross-sectional study was conducted among 83 NAFLD patients in Jahrom, Iran. Plasma levels of omentin-1, vaspin, hs-CRP and IL-6 were measured. Anthropometric indices, lipid profiles, liver enzymes as well as abdominal ultrasonography were assessed.

RESULTS

Partial correlations controlling for age and sex showed significant positive correlation between vaspin and fasting blood sugar (FBS), insulin, HOMA-IR, and hs-CRP. It has been observed that omentin negatively correlated with glucose levels. Moreover, a marginally significant association has been found between omentin levels and systolic blood pressure (SBP).

CONCLUSIONS

This study shows that vaspin and omentin-1 are associated with inflammation, insulin resistance and serum glucose levels in patients with NAFLD.

Low circulating chemerin levels correlate with hepatic dysfunction and increased mortality in decompensated liver cirrhosis

Nutritional status, infections, inflammation and extrahepatic organ dysfunction are critical factors for the progression of chronic liver disease. Chemerin is an immune-metabolically and chemotactically active adipokine and we hypothesized that it is associated with disease severity and prognosis in patients with advanced decompensated cirrhosis. Therefore, we measured serum concentrations of chemerin in a prospectively characterized cohort of 80 patients with decompensated cirrhosis and ascites and assessed the associations with markers of disease severity and short-term outcome at 28 days. In a subset of patients (n = 40), ascitic fluid chemerin was determined. Advanced liver disease was associated with decreased serum but not ascitic chemerin levels. Serum chemerin correlated with markers of hepatic function (total bilirubin, albumin, INR) and inversely correlated with indicators of portal hypertension (platelet count, gastrointestinal bleeding) but not with extrahepatic organ failure and systemic inflammation. Patients presenting with acute-on-chronic liver failure or infection did not exhibit altered serum or ascitic fluid chemerin concentrations. However, serum chemerin levels below 87 ng/ml predicted an increased risk for mortality or liver transplantation within 28 days independently of MELD and infections. We conclude that low serum chemerin is an independent adverse prognostic factor in patients with advanced decompensated cirrhosis.

Increased serum chemerin level to predict early onset of aortic valve stenosis

Inflammation appears to be the cause of aortic valve (AoV) stenosis and identification of predictive biomarkers is therefore imperative. The aim of the current study was to evaluate the potential role of serum chemerin and fibroblast growth factor-21 (FGF-21) in the pathogenesis of the disease. A total of 102 patients were selected based on certain criteria and divided into an aortic stenosis group and a control group. Patients with AoV stenosis were subdivided into three groups depending on the severity according to the echocardiography criteria: Aortic jet velocity, Vmax (m/sec); mean pressure gradient, PG (mmHg); aortic valve area (AVA), cm²; and indexed AVA, cm²/m². Patients were graded as: Severe: Vmax >4 m/sec, PG >40 mmHg, AVA <1.0 cm², indexed AVA <0.6; moderate: Vmax 3.0–4.0 m/sec, PG 20–40 mmHg, AVA 1.0–1.5 cm², indexed AVA 0.60–0.85; mild: Vmax 2.5–2.9 m/sec, PG <20 mmHg, AVA >1.5 cm², indexed AVA >0.85. ELISA was used for the detection of chemerin and FGF-21. Post-hoc analysis with Tukey's correction was performed. The highest chemerin levels were found in mild and moderate AoV stenosis and decreased along with the grade of severity, compared with the control group. The FGF-21 level was increased in all the stenosis groups, reaching the highest level at severe stenosis. Receiver-operating characteristic analysis of chemerin in all the AoV stenosis groups without grading the severity included, area under the curve (AUC)=0.76; 0.70–0.80= fair; P<0.001 and for mild AoV stenosis was AUC=0.82; 0.80–0.90= good; P<0.001. In conclusion, chemerin is a good diagnostic biomarker for mild AoV stenosis, while FGF-21 is a moderate diagnostic marker.

Adipokines in Liver Cirrhosis

Liver fibrosis can progress to cirrhosis, which is considered a serious disease. The Child-Pugh score and the model of end-stage liver disease score have been established to assess residual liver function in patients with liver cirrhosis. The development of portal hypertension contributes to ascites, variceal bleeding and further complications in these patients. A transjugular intrahepatic portosystemic shunt (TIPS) is used to lower portal pressure, which represents a major improvement in the treatment of patients. Adipokines are proteins released from adipose tissue and modulate hepatic fibrogenesis. These proteins affect various biological processes that are involved in liver function, including angiogenesis, vasodilation, inflammation and deposition of extracellular matrix proteins. The best studied adipokines are adiponectin and leptin. Adiponectin protects against hepatic inflammation and fibrogenesis, and leptin functions as a profibrogenic factor. These and other adipokines are supposed to modulate disease severity in patients with liver cirrhosis. Consequently, circulating levels of these proteins have been analyzed to identify associations with parameters of hepatic function, portal hypertension and its associated complications in patients with liver cirrhosis. This review article briefly addresses the role of adipokines in hepatitis and liver fibrosis. Here, studies having analyzed these proteins in systemic blood in cirrhotic patients are listed to identify adipokines that are comparably changed in the different cohorts of patients with liver cirrhosis. Some studies measured these proteins in systemic, hepatic and portal vein blood or after TIPS to specify the tissues contributing to circulating levels of these proteins and the effect of portal hypertension, respectively.

Serum omentin and vaspin levels in cirrhotic patients with and without portal vein thrombosis

AIM

To investigate serum omentin and vaspin levels in cirrhotic patients; and to assess the relationship of these levels with hemostatic parameters, metabolic abnormalities, cirrhosis severity and etiology.

METHODS

Fifty-one cirrhotic patients (17 with portal vein thrombosis) were analyzed. Serum omentin and vaspin levels were measured with commercially available direct enzyme-linked immunosorbent assays (ELISAs). To assess platelet activity, the following tests were performed using a MULTIPLATE^®PLATELET FUNCTION ANALYZER: (1) an ADP-induced platelet activation test; (2) a cyclooxygenase dependent aggregation test (ASPI test); (3) a von Willebrand factor and glycoprotein Ib-dependent aggregation (using ristocetin) test (RISTO test); and (4) a test for thrombin receptor-activating peptide-6 induced activation of the thrombin receptor, which is sensitive to IIb/IIIa receptor antagonists.

RESULTS

Omentin, but not vaspin, serum concentrations were significantly decreased in patients with portal vein thrombosis (PVT) (P = 0.01). Prothrombin levels were significantly increased in patients with PVT (P = 0.01). The thrombin receptor activating peptide (TRAP) test results were significantly lower in the PVT group (P = 0.03). No significant differences in adipokines serum levels were found regarding the etiology or severity of liver cirrhosis assessed according to the Child-Pugh or Model of End-Stage Liver Disease (MELD) scores. There was a significant increase in the TRAP (P = 0.03), ASPI (P = 0.001) and RISTO high-test (P = 0.02) results in patients with lower MELD scores. Serum omentin and vaspin levels were significantly down-regulated in patients without insulin resistance (P = 0.03, P = 0.02, respectively). A positive relationship between omentin and vaspin levels were found both when all of the patients were analyzed (r = 0.41, P = 0.01) and among those with PVT (r = 0.94, P < 0.001).

CONCLUSION

Serum omentin levels are increased in patients without PVT. Cirrhosis origin and grade do not affect omentin and vaspin levels. The analyzed adipokines do not influence platelet activity.

Chemokine-Like Receptor 1 Regulates the Proliferation and Migration of Vascular Smooth Muscle Cells

Background

We aimed to explore how chemokine-like receptor 1 (CMKLR1) influences the proliferation and migration of vascular smooth muscle cells (VSMCs).

Material/Methods

Normal VSMCs, negative control VSMCs interfered by CMKLR1 gene, and VSMCs with stable knockdown of CMKLR1 gene were divided into the control group, PDGF group, negative-shRNA group, and CMKLR1-shRNA group. Both cell number counting and BrdU incorporation assays were employed to investigate the proliferation status of VSMCs. Transwell migration assay was used to measure the migration status of VSMCs. Inflammation markers, including cytokines IL-1β, IL-6, TNF-α, and chemokines MCP-1 in VSMCs, were detected by real-time quantitative RT-PCR. Western blotting assay was used to detect protein expressions of the MAPK pathway in VSMCs.

Results

The number of VSMCs and the OD value of BrdU in PDGF group were significantly higher than those in the control group (both P<0.05). Compared with the control and negative-shRNA group, the CMKLR1-shRNA group exhibited significantly reduced VSMCs number and BrdU OD value (both P<0.05). Transwell migration assay indicated that PDGF-BB promoted whereas CMKLR1-shRNA inhibited the migration of VSMCs. The expression of IL-1β, IL-6, TNF-α, and MCP-1 were up-regulated in the PDGF group but down-regulated in the CMKLR1-shRNA group. Compared with normal VSMCs, the protein level of p-ERK1/2 was up-regulated in VSMCs treated with PDGF-BB, while it was down-regulated in the CMKLR1-shRNA group.

Conclusions

CMKLR1 exacerbated the proliferation and migration of VSMCs by activating ERK1/2.

Chemerin as an independent predictor of cardiovascular event risk

Currently, coronary artery disease (CAD) is considered a major ailment in humans with widespread prevalence. CAD also accounts for high mortality rates around the world that involves several known risk factors. Chemerin is a novel adipokinine that is associated with inflammation and adipogenesis. Furthermore, experimental and clinical data indicate that localized as well as circulating chemerin expression and activation are elevated in numerous metabolic and inflammatory diseases including psoriasis, obesity, type 2 diabetes, metabolic syndrome and cardiovascular disease. Chemerin is accepted as being a strong marker because the serum chemerin levels are increased in a CAD condition. However, the chimeric characteristics of chemerin have not been fully investigated. Although chemerin is known to be responsible for CAD development among other factors, authors still investigate it at the marker level. This review focuses on chemerin expression, processing, biological function and relevance to human diseases, and on the role of chemerin in the maintenance of a cardiovascular disease.

A Dormant Microbial Component in the Development of Preeclampsia

Preeclampsia (PE) is a complex, multisystem disorder that remains a leading cause of morbidity and mortality in pregnancy. Four main classes of dysregulation accompany PE and are widely considered to contribute to its severity. These are abnormal trophoblast invasion of the placenta, anti-angiogenic responses, oxidative stress, and inflammation. What is lacking, however, is an explanation of how these themselves are caused. We here develop the unifying idea, and the considerable evidence for it, that the originating cause of PE (and of the four classes of dysregulation) is, in fact, microbial infection, that most such microbes are dormant and hence resist detection by conventional (replication-dependent) microbiology, and that by occasional resuscitation and growth it is they that are responsible for all the observable sequelae, including the continuing, chronic inflammation. In particular, bacterial products such as lipopolysaccharide (LPS), also known as endotoxin, are well known as highly inflammagenic and stimulate an innate (and possibly trained) immune response that exacerbates the inflammation further. The known need of microbes for free iron can explain the iron dysregulation that accompanies PE. We describe the main routes of infection (gut, oral, and urinary tract infection) and the regularly observed presence of microbes in placental and other tissues in PE. Every known proteomic biomarker of "preeclampsia" that we assessed has, in fact, also been shown to be raised in response to infection. An infectious component to PE fulfills the Bradford Hill criteria for ascribing a disease to an environmental cause and suggests a number of treatments, some of which have, in fact, been shown to be successful. PE was classically referred to as endotoxemia or toxemia of pregnancy, and it is ironic that it seems that LPS and other microbial endotoxins really are involved. Overall, the recognition of an infectious component in the etiology of PE mirrors that for ulcers and other diseases that were previously considered to lack one.

Chemerin15-Ameliorated Cardiac Ischemia-Reperfusion Injury Is Associated with the Induction of Alternatively Activated Macrophages

Chemerin15 (C15), an endogenous anti-inflammatory component, inhibits the activity of neutrophils and macrophages through G protein-coupled receptor ChemR23; however, its role as well as functional mechanism in mouse myocardial ischemia/reperfusion (I/R) injury remains unknown. Methods. Sham or I/R operations were performed on C57BL/6J mice. The I/R mice received an injection of C15 immediately before reperfusion. Serum troponin T levels, infarct size, cardiomyocyte apoptosis, reactive oxygen species (ROS) production, and infiltration of neutrophils were assessed 24 h after reperfusion, while the macrophage phenotypes, macrophage infiltration, and inflammatory cytokine levels were assessed 48 h after reperfusion. Results. Compared with the control group, the C15-treated mice showed an obvious amelioration of I/R injury and displayed less ROS, accompanied by reduced neutrophil recruitment. C15 decreased the tumor necrosis factor- (TNF-) α and interleukin- (IL-) 6 levels and increased the IL-10 levels in the serum of the I/R mice, which suggested a suppressed inflammatory response that could be related to elevated alternatively activated M2 macrophages with characteristic skewed expression of M2 markers and inhibition of classically activated M1 marker expression. Conclusion. C15 may induce alternatively activated M2 macrophage polarization and suppress the inflammatory response to protect against myocardial I/R injury in mice.

Angiogenesis and liver fibrosis

Recent data indicate that hepatic angiogenesis, regardless of the etiology, takes place in chronic liver diseases (CLDs) that are characterized by inflammation and progressive fibrosis. Because anti-angiogenic therapy has been found to be efficient in the prevention of fibrosis in experimental models of CLDs, it is suggested that blocking angiogenesis could be a promising therapeutic option in patients with advanced fibrosis. Consequently, efforts are being directed to revealing the mechanisms involved in angiogenesis during the progression of liver fibrosis. Literature evidences indicate that hepatic angiogenesis and fibrosis are closely related in both clinical and experimental conditions. Hypoxia is a major inducer of angiogenesis together with inflammation and hepatic stellate cells. These profibrogenic cells stand at the intersection between inflammation, angiogenesis and fibrosis and play also a pivotal role in angiogenesis. This review mainly focuses to give a clear view on the relevant features that communicate angiogenesis with progression of fibrosis in CLDs towards the-end point of cirrhosis that may be translated into future therapies. The pathogenesis of hepatic angiogenesis associated with portal hypertension, viral hepatitis, non-alcoholic fatty liver disease and alcoholic liver disease are also discussed to emphasize the various mechanisms involved in angiogenesis during liver fibrogenesis.

Insulin resistance, adipokine profile and hepatic expression of SOCS-3 gene in chronic hepatitis C

AIM

To analyze adipokine concentrations, insulin resistance and hepatic expression of suppressor of cytokine signaling 3 (SOCS-3) in patients with chronic hepatitis C genotype 1 with normal body weight, glucose and lipid profile.

METHODS

The study group consisted of 31 patients with chronic hepatitis C and 9 healthy subjects. Total levels of adiponectin, leptin, resistin, visfatin, omentin, osteopontin and insulin were measured using an ELISA kit. The hepatic expression of SOCS-3 was determined by the use of the reverse transcription polymerase chain reaction method.

RESULTS

Homeostasis model assessment for insulin resistance (HOMA-IR) values were significantly higher in hepatitis C virus (HCV) infected patients without metabolic disorders compared to healthy controls (2.24 vs 0.59, P = 0.0003). Hepatic steatosis was observed in 32.2% of patients with HCV infection and was found in patients with increased HOMA-IR index (2.81 vs 1.99, P = 0.05) and reduced adiponectin level (5.96 vs 8.37, P = 0.04). Inflammatory activity (G ≥ 2) was related to increased osteopontin concentration (34.04 vs 23.35, P = 0.03). Advanced liver fibrosis (S ≥ 2) was associated with increased levels of omentin and osteopontin (436.94 vs 360.09, P = 0.03 and 32.84 vs 20.29, P = 0.03) and reduced resistin concentration (1.40 vs 1.74, P = 0.047). No correlations were reported between adipokine profile, HOMA-IR values and hepatic expression of the SOCS-3 gene.

CONCLUSION

We speculated that no relationship between adipokines and HOMA-IR values may indicate that HCV can induce insulin resistance itself. Some adipokines appear to be biochemical markers of steatosis, inflammation and fibrosis in patients with chronic HCV infection. © 2014 Baishideng Publishing Group Inc. All rights reserved.

Hepatic chemerin and chemokine-like receptor 1 expression in patients with chronic hepatitis C

INTRODUCTION

Chemerin seems to be involved in pathogenesis of chronic hepatitis C (CHC). Hepatic expressions of chemerin and its receptor, chemokine receptor-like 1 (CMKLR1), in CHC have not been studied so far.

AIM

To evaluate chemerin and CMKLR1 hepatic expression together with serum chemerin concentration in CHC patients and to assess their relationship with metabolic and histopathological abnormalities.

METHODS

The study included 63 nonobese CHC patients. Transcription of chemerin and CMKLR1 was assessed by quantitative real-time PCR, while serum chemerin was assessed by enzyme-linked immunosorbent assay.

RESULTS

Expression of chemerin and CMKLR1 was present in the liver of all CHC patients regardless of sex or age. This expression was not associated with necroinflammatory activity and steatosis grade, fibrosis stage, and metabolic abnormalities. There was a negative association between serum chemerin and chemerin hepatic expression (r = (-0.41), P = 0.006).

CONCLUSION

The study for the first time confirmed a marked expression of chemerin and CMKLR1 in the liver of CHC patients. The study was performed using the homogenates of human liver tissue, so it is not possible to define whether hepatocytes or other cell types which are abundantly represented in the liver constitute the main source of chemerin and CMKLR1 mRNA.

Impact of serum chemerin levels on liver functional reserves and platelet counts in patients with hepatocellular carcinoma

Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis.

Angiogenesis: a phenomenon which aggravates chronic liver disease progression

It has become increasingly clear that angiogenesis occurring during chronic wound healing and fibrogenesis provides a key contribution to disease progression and complications. The association of fibrogenesis and angiogenesis should be regarded as crucial in the modern evaluation of liver disease progression and in the search for therapeutic targets. Physiological hepatic angiogenesis occurs during liver regeneration, contributing to the formation of new functional sinusoids. Pathological angiogenesis in liver is characterized by intrahepatic vascular remodeling with capillarization of the sinusoids and development of intrahepatic shunts, which lead to increased hepatic resistance and decreased effective hepatocyte perfusion. The problem of angiogenesis in chronic hepatitis C and nonalcoholic fatty liver disease has not been fully resolved. This manuscript briefly describes pathogenesis of new blood vessel formation in chronic hepatitis and potential role of angiogenesis in disease progression.

Chemerin158K protein is the dominant chemerin isoform in synovial and cerebrospinal fluids but not in plasma

Chemerin is a chemoattractant involved in immunity that may also function as an adipokine. Chemerin circulates as an inactive precursor (chem163S), and its activation requires proteolytic cleavages at its C terminus, involving proteases involved in coagulation, fibrinolysis, and inflammation. However, the key proteolytic steps in prochemerin activation in vivo remain to be established. Previously, we have shown that C-terminal cleavage of chem163S by plasmin to chem158K, followed by a carboxypeptidase cleavage, leads to the most active isoform, chem157S. To identify and quantify the in vivo chemerin isoforms in biological specimens, we developed specific ELISAs for chem163S, chem158K, and chem157S, using antibodies raised against peptides from the C terminus of the different chemerin isoforms. We found that the mean plasma concentrations of chem163S, chem158K, and chem157S were 40 ± 7.9, 8.1 ± 2.9, and 0.7 ± 0.8 ng/ml, respectively. The total level of cleaved and noncleaved chemerins in cerebrospinal fluids was ∼10% of plasma levels whereas it was elevated ∼2-fold in synovial fluids from patients with arthritis. On the other hand, the fraction of cleaved chemerins was much higher in synovial fluid and cerebrospinal fluid samples than in plasma (∼75%, 50%, and 18% respectively). Chem158K was the dominant chemerin isoform, and it was not generated by ex vivo processing, indicating that cleavage of prochemerin at position Lys-158, whether by plasmin or another serine protease, represents a major step in prochemerin activation in vivo. Our study provides the first direct evidence that chemerin undergoes extensive proteolytic processing in vivo, underlining the importance of measuring individual isoforms.

Serum levels of vaspin, obestatin, and apelin-36 in patients with nonalcoholic fatty liver disease

The novel adipokines vaspin, obestatin, and apelin-36 are associated with insulin resistance and the components of the metabolic syndrome. We assayed circulating levels of these molecules and examined their association with clinical, biochemical, and histologic phenotypes in patients with nonalcoholic fatty liver disease (NAFLD). Serum levels of vaspin, obestatin, and apelin-36 were assayed by enzyme-linked immunosorbent assay in 91 patients with biopsy-proven NAFLD and 81 controls. We analyzed associations between adipokines and the characteristics of patients with NAFLD using multivariable linear regression models. Univariable analysis showed that concentrations of vaspin and apelin-36 were significantly higher in patients with NAFLD than in controls, whereas no differences in obestatin levels were found. Serum vaspin levels showed a statistically significant association with C-reactive protein (r = 0.378, P < .001) and liver fibrosis scores (r = 0.401, P < .001), whereas apelin-36 levels showed a modest association with homeostasis model assessment of insulin resistance (r = 0.204, P < .01). After stepwise linear regression analysis, serum vaspin levels were the only independent predictor of liver fibrosis scores in patients with NAFLD (β = 0.37, t = 3.99, P < .01). Serum vaspin levels are raised in patients with NAFLD regardless of potential confounders and represent an independent predictor of liver fibrosis scores. These findings support further investigation of this novel adipokine in metabolic liver diseases.

Serum visfatin is correlated with disease severity and metabolic syndrome in chronic hepatitis C infection

BACKGROUND AND AIM

Cytokines activation is a common feature in chronic hepatitis C (CHC) infection. Visfatin, as a recently-recognized adipocytokine, may correlate with metabolic abnormalities. We aimed to elucidate the characteristics of visfatin in CHC patients.

METHODS

This retrospective study included 102 treatment-naïve CHC patients and 97 sex-/age-matched healthy adults. Serum visfatin levels were examined by an enzyme linked immunosorbent assay test. The correlation between visfatin and hepatitis C virus (HCV) infection in terms of virological, metabolic, and histopathological profiles was analyzed. The impact of visfatin on the treatment response to pegylated interferon plus ribavirin (PEGIFN/RBV) therapy was also assessed.

RESULTS

The visfatin level was correlated significantly with fibrosis scores (r = 0.23, P = 0.02) in CHC patients. A significant higher visfatin level was observed in CHC patients with histological activity index scores of mild and more (P = 0.01) and advanced fibrosis (P = 0.04). The mean visfatin level (0.81 ± 0.28 log ng/mL) of 26 CHC patients with metabolic syndrome was significantly lower than their counterparts (0.95 ± 0.30 log ng/mL) (P = 0.03). There was no significant correlation between visfatin and HCV genotypes, viral load, and treatment response to PEGIFN/RBV therapy. Multiple logistic regression analyses demonstrated that metabolic syndrome was the leading negative variable (odds ratio = 0.09, 95% confidence interval = 0.02-0.46, P = 0.004) associated with high visfatin level, followed by advanced fibrosis (odds ratio = 2.88, 95% confidence interval = 1.06-6.78, P = 0.03).

CONCLUSIONS

Serum visfatin was correlated with disease severity and metabolic syndrome in CHC patients.