Ferritin, metabolic syndrome and NAFLD: elective attractions and dangerous liaisons

Serum Ferritin Levels and Liver-Related Events in Individuals With Steatotic Liver Disease: A Longitudinal Cohort Study

BACKGROUND

Serum ferritin has been suggested as a potential biomarker associated with disease progression in metabolic dysfunction-associated steatotic liver disease (MASLD).

AIMS

We investigated the association between serum ferritin levels and liver-related events (LREs) in individuals with steatotic liver disease (SLD).

METHODS

This cohort study included 17,560 adults with SLD (MASLD [n = 15,744], MASLD with increased alcohol intake (MetALD) [n = 1103] and cryptogenic SLD [n = 713]) without LRE at baseline. A steatotic liver was diagnosed using ultrasound, and LRE was defined as the development of decompensation (ascites, variceal bleeding and hepatic encephalopathy) or hepatocellular carcinoma. Participants were categorised into high (≥ 300 μg/L for males, ≥ 200 μg/L for females) or normal to low (< 300 μg/L for males, < 200 μg/L for females) ferritin levels.

RESULTS

During 211,425 person-years of follow-up (median: 12.3 years), 74 incident LRE cases were identified, with 63 cases in MASLD, 10 in MetALD and 1 in cryptogenic SLD. The multivariable-adjusted hazard ratio (aHR) for LRE comparing individuals with high and normal-to-low ferritin level was 3.13 (95% confidence interval [CI] 1.89-5.18). Increased risk of LRE in individuals with high serum ferritin level compared to those with normal to low serum ferritin level was consistent across SLD subtypes (aHR 2.69, 95% CI 1.55-4.67 for MASLD; aHR 5.73, 95% CI 1.31-25.0 for MetALD), and SLD severity assessed by Fibrosis-4 (FIB-4) index (aHR 2.38, 95% CI 1.34-4.21 for FIB-4 ≥ 1.3; aHR 3.13, 95% CI 1.18-8.29 for FIB-4 < 1.3).

CONCLUSIONS

Serum ferritin levels correlated with the risk of LRE in patients with SLD.

Obeticholic acid's effect on HDL function in MASH varies by diabetic status

Inflammation and oxidative stress are the key factors in the pathogenesis of both metabolic dysfunction-associated steatohepatitis (MASH) and atherosclerosis. Obeticholic acid (OCA), a farnesoid X receptor (FXR) agonist, improves hepatic inflammation and fibrosis in patients with MASH. However, it also reduces HDL cholesterol, suggesting that OCA may increase cardiovascular disease (CVD) risk in patients with MASH. We assessed HDL cholesterol efflux function, antioxidant (paraoxonase and ceruloplasmin activity), pro-inflammatory index, and particle sizes in a small group of patients with and without diabetes (n = 10/group) at baseline and after 18 months of OCA treatment. Patients on lipid-lowering medications (statins, fibrates) were excluded. At baseline, ferritin levels were higher in patients with MASH without diabetes (336.5 [157.0, 451.0] vs. 83 [36.0, 151.0] ng/mL, p < 0.005). Markers of HDL functions were similar in both groups. OCA therapy significantly improved liver histology and liver enzymes but increased alkaline phosphatase levels in nondiabetic patients with MASH (p < 0.05). However, it did not have any significant effect on cholesterol efflux and the antioxidant paraoxonase functions. In nondiabetics, ceruloplasmin (CP) antioxidant activity decreased (p < 0.005) and the pro-inflammatory index of HDL increased (p < 0.005) due to OCA therapy. In contrast, in diabetics, OCA increased levels of pre-β-HDL-the HDL particles enhanced protective capacity (p = 0.005) with no alteration in HDL functionality. In all patients, serum glucose levels were negatively correlated with OCA-induced change in pro-inflammatory function in HDL (p < 0.001), which was primarily due to diabetes (p = 0.05). These preliminary results suggest a distinct effect of OCA therapy on diabetic and nondiabetic patients with MASH and warrant a future large-scale study.

Circulating Ferritin in Patients with Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

Objectives

To synthesize data on circulating ferritin between patients with histologically confirmed nonalcoholic fatty liver disease (NAFLD) and non-NAFLD controls.

Methods

A systematic literature search was conducted in PubMed, Scopus, and the Cochrane Library. Thirty-one studies comprising data on 5631 individuals (2929 biopsy-proven NAFLD patients and 2702 controls) were included in the meta-analysis.

Results

Higher circulating ferritin levels were observed in NAFLD patients than in controls [standardized mean difference (SMD) 1.14; 95% confidence interval (95% CI) 0.73-1.55], in patients with simple nonalcoholic fatty liver (NAFL) than in controls (SMD 0.57; 95% CI 0.34-0.80), in patients with nonalcoholic steatohepatitis (NASH) than in controls (SMD 0.95; 95% CI 0.69-1.22), and in NASH than in NAFL patients (SMD 0.62; 95% CI 0.25-0.99). There was moderate-to-high heterogeneity among studies in the above pairs of comparisons (I2 = 68-97%); no risk of publication bias was observed by Egger's test (P = 0.81, P = 0.72, P = 0.59, P = 0.42, respectively). The heterogeneity was reduced in the subgroup of biopsy-proven controls in all pairs of comparisons (I2 = 0-65%). The heterogeneity was also reduced after excluding studies with the Newcastle-Ottawa Scale (NOS) score <7 (n = 10) for the comparison of NAFLD patients vs. controls (I2 = 54%, P = 0.02). The meta-regression analysis revealed that the male ratio was positively associated with ferritin SMD in the comparison between NAFLD patients and controls and accounted for 32.7% (P = 0.002) of the heterogeneity in this pair of comparison.

Conclusions

Circulating ferritin was higher in NAFLD (or NAFL or NASH) patients compared with controls. Higher levels of circulating ferritin were also associated with the severity of the disease, which, however, should be cautiously interpreted.PROSPERO registration ID: CRD42022354025.

Serum ferritin levels can predict long-term outcomes in patients with metabolic dysfunction-associated steatotic liver disease

OBJECTIVE

Hyperferritinaemia is associated with liver fibrosis severity in patients with metabolic dysfunction-associated steatotic liver disease (MASLD), but the longitudinal implications have not been thoroughly investigated. We assessed the role of serum ferritin in predicting long-term outcomes or death.

DESIGN

We evaluated the relationship between baseline serum ferritin and longitudinal events in a multicentre cohort of 1342 patients. Four survival models considering ferritin with confounders or non-invasive scoring systems were applied with repeated five-fold cross-validation schema. Prediction performance was evaluated in terms of Harrell's C-index and its improvement by including ferritin as a covariate.

RESULTS

Median follow-up time was 96 months. Liver-related events occurred in 7.7%, hepatocellular carcinoma in 1.9%, cardiovascular events in 10.9%, extrahepatic cancers in 8.3% and all-cause mortality in 5.8%. Hyperferritinaemia was associated with a 50% increased risk of liver-related events and 27% of all-cause mortality. A stepwise increase in baseline ferritin thresholds was associated with a statistical increase in C-index, ranging between 0.02 (lasso-penalised Cox regression) and 0.03 (ridge-penalised Cox regression); the risk of developing liver-related events mainly increased from threshold 215.5 µg/L (median HR=1.71 and C-index=0.71) and the risk of overall mortality from threshold 272 µg/L (median HR=1.49 and C-index=0.70). The inclusion of serum ferritin thresholds (215.5 µg/L and 272 µg/L) in predictive models increased the performance of Fibrosis-4 and Non-Alcoholic Fatty Liver Disease Fibrosis Score in the longitudinal risk assessment of liver-related events (C-indices>0.71) and overall mortality (C-indices>0.65).

CONCLUSIONS

This study supports the potential use of serum ferritin values for predicting the long-term prognosis of patients with MASLD.

Hereditary Hyperferritinemia

Ferritin is a ubiquitous protein that is present in most tissues as a cytosolic protein. The major and common role of ferritin is to bind Fe²⁺, oxidize it and sequester it in a safe form in the cell, and to release iron according to cellular needs. Ferritin is also present at a considerably low proportion in normal mammalian sera and is relatively iron poor compared to tissues. Serum ferritin might provide a useful and convenient method of assessing the status of iron storage, and its measurement has become a routine laboratory test. However, many additional factors, including inflammation, infection, metabolic abnormalities, and malignancy-all of which may elevate serum ferritin-complicate interpretation of this value. Despite this long history of clinical use, fundamental aspects of the biology of serum ferritin are still unclear. According to the high number of factors involved in regulation of ferritin synthesis, secretion, and uptake, and in its central role in iron metabolism, hyperferritinemia is a relatively common finding in clinical practice and is found in a large spectrum of conditions, both genetic and acquired, associated or not with iron overload. The diagnostic strategy to reveal the cause of hyperferritinemia includes family and personal medical history, biochemical and genetic tests, and evaluation of liver iron by direct or indirect methods. This review is focused on the forms of inherited hyperferritinemia with or without iron overload presenting with normal transferrin saturation, as well as a step-by-step approach to distinguish these forms to the acquired forms, common and rare, of isolated hyperferritinemia.

A prospective cohort study of the use of the fatty liver index and Fibroscan to determine the prevalence of fatty liver disease in an Irish population

OBJECTIVES

Rates of nonalcoholic fatty liver disease (NAFLD) are increasing worldwide. The fatty liver index (FLI) is a noninvasive predictor of NAFLD. This prospective cohort study used the FLI to estimate the prevalence of NAFLD in patients attending an Irish Acute Medical Unit (AMU), and assessed the degree of fibrosis in this group using Fibroscan.

METHODS

Patients attending the AMU over a 3-month period were invited to participate. Patients with excess alcohol consumption or pre-existing liver disease were excluded. Using established FLI cut-offs, 414 participants were grouped into low (FLI ≤ 30), medium (30 < FLI ≤ 60) and high (FLI > 60) risk of NAFLD. High-risk patients were offered review including liver stiffness measurement (LSM) and controlled attenuation parameter (CAP) score.

RESULTS

A total of 134 patients were at low-risk, 96 at medium-risk and 184 at high-risk of NAFLD. Male sex (P < 0.0001) and increasing age (P < 0.0001) were associated with higher risk. Of the 120 high-risk patients who attended follow up, 13 participants had LSM > 7 kPa. Higher FLI scores were associated with higher CAP scores (P < 0.0001) but did not predict higher LSMs. Fasting glucose and HbA1c were found to be associated with higher LSM.

CONCLUSION

About 44.4% of patients presenting to the AMU were at high risk of NAFLD according to the FLI. Only 10.8% of the high-risk group, and 3% of all those recruited had a LSM > 7 kPa suggesting development of fibrosis.

Identification of Novel Mutations by Targeted NGS Panel in Patients with Hyperferritinemia

BACKGROUND

Several inherited diseases cause hyperferritinemia with or without iron overload. Differential diagnosis is complex and requires an extensive work-up. Currently, a clinical-guided approach to genetic tests is performed based on gene-by-gene sequencing. Although reasonable, this approach is expensive and time-consuming and Next Generation Sequencing (NGS) technology may provide cheaper and quicker large-scale DNA sequencing.

METHODS

We analysed 36 patients with non-HFE-related hyperferritinemia. Liver iron concentration was measured in 33 by magnetic resonance. A panel of 25 iron related genes was designed using SureDesign software. Custom libraries were generated and then sequenced using Ion Torrent PGM.

RESULTS

We identified six novel mutations in SLC40A1, three novel and one known mutation in TFR2, one known mutation and a de-novo deletion in HJV, and a novel mutation in HAMP in ten patients. In silico analyses supported the pathogenic role of the mutations.

CONCLUSIONS

Our results support the use of an NGS-based panel in selected patients with hyperferritinemia in a tertiary center for iron metabolism disorders. However, 26 out of 36 patients did not show genetic variants that can individually explain hyperferritinemia and/or iron overload suggesting the existence of other genetic defects or gene-gene and gene-environment interactions needing further studies.

Correlation between HDL2, HDL3 and serum ferritin levels with fatty liver and NAFLD activity score (NAS) in liver histology of organ donors

Background

Nonalcoholic fatty liver disease (NAFLD) is one of the most important liver diseases. High-density lipoprotein (HDL) has anti-atherogenic properties and its reduction can be associated with fatty liver. Serum ferritin levels are usually elevated in patients with NAFLD. This study aimed to evaluate the correlation between HDL subtypes and serum ferritin levels with evidence of NAFLD in liver histology of organ donors.

Methods

One hundred organ donor patients who were eligible for the study were included in the study and ferritin; HDL2 and HDL3 were measured in blood samples. Donated liver tissue biopsy specimens were evaluated for fatty liver and NAFLD activity score (NAS). In addition, AST and ALT were measured in recipients 24 h after transplant. All data abstracted and analyzed statistically.

Results

Serum HDL2 levels and HDL2/HDL3 ratio in patients with NAS > 1 were significantly lower (P < 0.05). Serum levels of HDL3 and ferritin were not significantly associated with NAS >1 (P > 0.05). In addition, serum ferritin > 1000 ng/ml in organ donors associated with increased AST and ALT levels 24 h after transplantation in the liver organ recipient.

Conclusions

Lower HDL2 values and HDL2/HDL3 ratio were associated with increased NAFLD activity score, but HDL3 and ferritin did not show such a relationship. In addition, higher levels of ferritin in organ donors may be associated with increased AST and ALT 24 h after liver transplantation in the organ recipient.

Albuminuria Is Associated with Hepatic Iron Load in Patients with Non-Alcoholic Fatty Liver Disease and Metabolic Syndrome

Background: Increased albuminuria is associated with increased serum ferritin, insulin resistance, and non-alcoholic fatty liver disease (NAFLD). Liver iron accumulation is also related to hyperferritinemia, insulin resistance, and NAFLD; however, there is no evidence on its relationship with albuminuria. Aims: To assess the relationship between hepatic iron load and urine albumin-to-creatinine ratio (UACR) in patients with metabolic syndrome (MetS) and NAFLD. Methods: In total, 75 MetS and NAFLD patients (aged 40–60 years, BMI 27–40 kg/m²) were selected from a cohort according to available data on hepatic iron load (HepFe) by magnetic resonance imaging (MRI). Subjects underwent anthropometric measurements, biochemistry testing, and liver MRI. Increased albuminuria was defined by UACR. Results: UACR correlated with NAFLD, HepFe, triglycerides, serum ferritin, fasting insulin, insulin resistance (calculated using the homeostatic model assessment for insulin resistance—HOMA-IR- formula), and platelets (p < 0.05). Multiple regression analysis adjusted for gender, age, eGFR, HbA1c, T2DM, and stages of NAFLD, found that HepFe (p = 0.02), serum ferritin (p = 0.04), fasting insulin (p = 0.049), and platelets (p = 0.009) were associated with UACR (R² = 0.370; p = 0.007). UACR, liver fat accumulation, serum ferritin, and HOMA-IR increased across stages of HepFe (p < 0.05). Patients with severe NAFLD presented higher HepFe, fasting insulin, HOMA-IR, and systolic blood pressure as compared to patients in NAFLD stage 1 (p < 0.05). Conclusion: Hepatic iron load, serum ferritin, fasting insulin, and platelets were independently associated with albuminuria. In the context of MetS, increased stages of NAFLD presented higher levels of HepFe. Higher levels of HepFe were accompanied by increased serum ferritin, insulin resistance, and UACR. The association between iron accumulation, MetS, and NAFLD may represent a risk factor for the development of increased albuminuria.

Dietary iron to total energy intake ratio and type 2 diabetes incidence in a longitudinal 12-year analysis of the Korean Genome and Epidemiology Cohort Study

PURPOSE

Recent study found iron consumption has been associated with an increased risk of type 2 diabetes (T2DM). Even though, high iron intake is correlated with total caloric intake, most studies have evaluated the individual effect of iron and total caloric intake. The aim of this study was to investigate the effect of iron intake, in conjunction with total energy intake, on developing T2DM. We also investigated the interactions between dietary iron and energy ratios (IERs) and iron-related single nucleotide polymorphisms (SNPs) in the development of T2DM.

METHODS

The study was carried out in Ansan and Ansung, Korea, between March 2001 and December 2014. A total of 6413 participants (3073 men and 3340 women), aged 40-69 years, were enrolled in this study. The mean follow-up period was 8.4 years. The study population was divided into quartiles based on IERs with cut-off points at 4.54, 5.41, and 6.29. The odds ratios (ORs) for new-onset T2DM were calculated across each quartile of IERs and a random forest model was constructed using the default settings to predict new-onset T2DM. To confirm the interaction among IERs, SNPs, and the incidence of T2DM, we measured the predictive power of new-onset T2DM using IER and six SNPs in genes related to iron metabolism [rs855791 (TPMRSS6), rs38116479 (TF), rs1799852 (TF), rs2280673, rs1799945 (HFT), rs180562 (HFE)].

RESULTS

The prevalence of T2DM was 762 (11.8%). IERs showed a positive association with T2DM. The ORs were 1.30 (95% CI 1.02-1.67), 1.20 (95% CI 0.94-1.56), and 1.43 (95% CI 1.11-1.86) across the IER quartiles after adjusting for non-dietary and dietary metabolic risk factors. When the IER was 1.89-fold higher than the reference group, the risk of developing T2DM increased by 43% (OR 1.43; 95% CI 1.11-1.86).

CONCLUSION

A higher IER was positively associated with developing T2DM independent of dietary or non-dietary risk factors. We also found the possible interactions between the identified SNPs and iron intake in relations to T2DM.

Hyperferritinemia-A Clinical Overview

Ferritin is one of the most frequently requested laboratory tests in primary and secondary care, and levels often deviate from reference ranges. Serving as an indirect marker for total body iron stores, low ferritin is highly specific for iron deficiency. Hyperferritinemia is, however, a non-specific finding, which is frequently overlooked in general practice. In routine medical practice, only 10% of cases are related to an iron overload, whilst the rest is seen as a result of acute phase reactions and reactive increases in ferritin due to underlying conditions. Differentiation of the presence or absence of an associated iron overload upon hyperferritinemia is essential, although often proves to be complex. In this review, we have performed a review of a selection of the literature based on the authors’ own experiences and assessments in accordance with international recommendations and guidelines. We address the biology, etiology, and epidemiology of hyperferritinemia. Finally, an algorithm for the diagnostic workup and management of hyperferritinemia is proposed, and general principles regarding the treatment of iron overload are discussed.

D-Dimer and Serum ferritin as an Independent Risk Factor for Severity in COVID-19 Patients

Ferritin is an intracellular blood protein that contains iron, covid-19 diseases is an infectious disease caused by a virus called corona virus, the infected person mostly experiences mild to moderate respiratory illness ferritin level in blood mostly depend on severity of the covid-19 disease. Ferritin level could be used as an indicator for the covid-19 disease. Within 120 corona virus patients that used as individual in this study, the ferritin level in the blood were tested, also each of (D-Dimer, ESR, C.R protein) Depend on the results, the patients with over 60 years have a high ferritin level also the d-dimer were abnormal with 65% higher than normal range.

Elevated serum ferritin level effectively discriminates severity illness and liver injury of coronavirus disease 2019 pneumonia

Aim

Ferritin is a hepatic protein that plays vital roles in diagnosing and predicting diseases, but its potential in coronavirus disease 2019 (COVID-19) remains unknown.

Method

We collected clinical records from 79 COVID-19 patients at Wuhan Union hospital (China). Spearman’s correlation analysis, receiver operating characteristic (ROC) curve and Kaplan–Meier survival curves were employed.

Results

Patients with elevated ferritin levels had a higher incidence of severity illness (50.0 vs 2.9%) and liver injury (52.3 vs 20.0%) when compared with patients with normal ferritin levels (p < 0.05). Ferritin could effectively identify the severity of illness (ROC area 0.873) and liver injury (ROC area 0.752). The elevated ferritin group showed longer viral clearance time (median 16 vs 6 days, p < 0.001) and in-hospital length (median 18 vs 10 days, p < 0.001).

Conclusions

It suggests that ferritin could act as an easy-to-use tool to identify liver injury and severity illness and predict the prognosis of COVID-19 patients. Intensive surveillance is necessary for patients with abnormal ferritin levels.

Renaming NAFLD to MAFLD: Could the LDE System Assist in This Transition?

Our understanding of fatty liver syndromes and their relationship with the metabolic syndrome has improved over recent decades and, paralleling this, we are now at the dawn of the NAFLD (nonalcoholic fatty liver disease) to MAFLD (metabolic-associated fatty liver disease) transition. The pitfalls of NAFLD diagnosis, together with disappointing results in therapeutic trials, and the inconsistencies and risks inherent in a "negative" definition (such as "nonalcoholic") as opposed to a "positive" one (i.e., "metabolic") are predicted to facilitate the proposed renaming of NAFLD to MAFLD. However, a premature change of terminology would not necessarily address major unmet needs in this area, and may even become counterproductive. As an aid to selecting more homogeneous cohorts of patients, I propose the LDE (Liver, Determinants, Extra-hepatic) classification system which, in principle, may help to assess the natural course of disease as well as the efficacy of novel drugs in patients with NAFLD/MAFLD.

Evaluating the association of serum ferritin and hepatic iron with disease severity in non-alcoholic fatty liver disease

BACKGROUND & AIMS

Hyperferritinemia, with or without increased hepatic iron, represents a common finding in non-alcoholic fatty liver disease (NAFLD). However, it is unclear whether it reflects hepatic inflammation or true iron-overload and, in case the latter is confirmed, whether this influences disease progression. We therefore explored the association between serum ferritin, degree and pattern of hepatic iron deposition and liver disease severity in patients with NAFLD.

METHODS

We selected 468 patients with biopsy-proven NAFLD from 2 European centres. Iron, hepatic and metabolic parameters were collected at the time of liver biopsy. Iron deposits in hepatocytes and reticuloendothelial cells were assessed and graded. Diagnosis of non-alcoholic steatohepatitis (NASH) and fibrosis staging were performed.

RESULTS

A total of 122 (26%) patients had hyperferritinemia, whereas stainable hepatic iron was found in 116 (25%) patients (38% predominantly in hepatocytes, 20% in reticuloendothelial cells and 42% in both). Subjects with stainable hepatic iron, particularly those with a mixed pattern, had higher serum ferritin and transaminases but only a mixed pattern of iron deposition was among the variables significantly associated with presence of NASH. Serum ferritin was not associated with presence of NASH, however it increased with worsening fibrosis stage (F3 compared to F0-F1), and significantly decreased in stage F4.

CONCLUSIONS

A mixed pattern of hepatic iron deposition is associated with the presence of steatohepatitis, while serum ferritin increases with worsening fibrosis up to pre-cirrhotic stage. In individual NAFLD patients, serum ferritin could be evaluated as part of non-invasive diagnostic panels but not on its own.

Loss of RIP3 initiates annihilation of high-fat diet initialized nonalcoholic hepatosteatosis: A mechanism involving Toll-like receptor 4 and oxidative stress

Non-alcoholic fatty liver disease (NAFLD) is a prevalent and complex disease that confers a high risk of severe liver disorders. Although such public and clinical health importance, very few effective therapies are presently available for NAFLD. Here, we showed that receptor-interacting kinase-3 (RIP3) was up-regulated in liver of mouse with hepatic steatosis induced by high fat diet (HFD). After 16 weeks on a HFD, obesity, insulin resistance, metabolic syndrome, hepatic steatosis, inflammatory response and oxidative stress were significantly alleviated in liver of mice with the loss of RIP3. We provided mechanistic evidence that RIP3 knockdown attenuated hepatic dyslipidemia through preventing the expression of lipogenesis-associated genes. Furthermore, in the absence of RIP3, the transcription factor of nuclear factor-κB (NF-κB) signaling pathway activated by HFD was blocked, accompanied with the inhibition of NLRP3 inflammasome. We also found that RIP3 knockdown-induced activation of nuclear factor-erythroid 2 related factor 2/heme oxygenase-1 (Nrf-2/HO-1) led to the inhibition of oxidative stress. The detrimental effects of RIP3 on hepatic steatosis and related pathologies were confirmed in palmitate (PAL)-treated mouse liver cells. Of note, lipopolysaccharide (LPS)- or PAL-activated TLR-4 resulted in the up-regulation of RIP3 that was accompanied by the elevated inflammation and lipid deposition, and these effects were reversed in TLR-4 knockdown cells. Furthermore, promoting Nrf-2 pathway activation effectively reduced reactive oxygen species (ROS) generation and RIP3 expression in PAL-stimulated cells, consequently leading to the suppression of cellular inflammation and lipid accumulation. In contrast, blocking Nrf-2/HO-1 signaling abrogated RIP3 knockdown-reduced reactive oxygen species (ROS), inflammatory response and lipid deposition in PAL-stimulated cells. Taken together, the present study helped to elucidate how HFD-induced hepatic steatosis was regulated by RIP3, via the TLR-4/NF-κB and Nrf-2/HO-1 signaling pathways.

Vascular Damage in Patients with Nonalcoholic Fatty Liver Disease: Possible Role of Iron and Ferritin

Non Alcoholic Fatty Liver Disease (NAFLD) is the most common chronic liver disease in Western countries. Recent data indicated that NAFLD is a risk factor by itself contributing to the development of cardiovascular disease independently of classical known risk factors. Hyperferritinemia and mild increased iron stores are frequently observed in patients with NAFLD and several mechanisms have been proposed to explain the role of iron, through oxidative stress and interaction with insulin metabolism, in the development of vascular damage. Moreover, iron depletion has been shown to decrease atherogenesis in experimental models and in humans. This review presents the recent evidence on epidemiology, pathogenesis, and the possible explanation of the role of iron and ferritin in the development of cardiovascular damage in patients with NAFLD, and discusses the possible interplay between metabolic disorders associated with NAFLD and iron in the development of cardiovascular disease.

Biomarkers of Metabolic Syndrome: Biochemical Background and Clinical Significance

Biomarkers of the metabolic syndrome are divided into four subgroups. Although dividing them in groups has some limitations, it can be used to draw some conclusions. In a first part, the dyslipidemias and markers of oxidative stress are discussed, while inflammatory markers and cardiometabolic biomarkers are reviewed in a second part. For most of them, the biochemical background and clinical significance are discussed, although here also a well-cut separation cannot always be made. Altered levels cannot always be claimed as the cause, risk, or consequence of the syndrome. Several factors are interrelated to each other and act in a concerted, antagonistic, synergistic, or modulating way. Most important conclusions are summarized at the end of every reviewed subgroup. Genetic biomarkers or influences of various food components on concentration levels are not included in this review article.

Low Serum Hepcidin in Patients with Autoimmune Liver Diseases

Hepcidin, a liver hormone, is important for both innate immunity and iron metabolism regulation. As dysfunction of the hepcidin pathway may contribute to liver pathology, we analysed liver hepcidin mRNA and serum hepcidin in patients with chronic liver diseases. Hepcidin mRNA levels were determined in liver biopsies obtained from 126 patients with HCV (n = 21), HBV (n = 23), autoimmune cholestatic disease (primary biliary cirrhosis and primary sclerosing cholangitis; PBC/PSC; n = 34), autoimmune hepatitis (AIH; n = 16) and non-alcoholic fatty liver disease (NAFLD; n = 32). Sera sampled on the biopsy day from the same patients were investigated for serum hepcidin levels. Hepatic hepcidin mRNA levels correlated positively with ferritin and negatively with serum γ-GT levels. However, no correlation was found between serum hepcidin and either ferritin or liver hepcidin mRNA. Both serum hepcidin and the serum hepcidin/ferritin ratio were significantly lower in AIH and PBC/PSC patients’ sera compared to HBV, HCV or NAFLD (P<0.001 for each comparison) and correlated negatively with serum ALP levels. PBC/PSC and AIH patients maintained low serum hepcidin during the course of their two-year long treatment. In summary, parallel determination of liver hepcidin mRNA and serum hepcidin in patients with chronic liver diseases shows that circulating hepcidin and its respective ratio to ferritin are significantly diminished in patients with autoimmune liver diseases. These novel findings, once confirmed by follow-up studies involving bigger size and better-matched disease subgroups, should be taken into consideration during diagnosis and treatment of autoimmune liver diseases.

Simultaneous liver iron and fat measures by magnetic resonance imaging in patients with hyperferritinemia

OBJECTIVE

Hyperferritinemia is frequent in chronic liver diseases of any cause, but the extent to which ferritin truly reflects iron stores is variable. In these patients, both liver iron and fat are found in variable amount and association. Liver biopsy is often required to quantify liver fat and iron, but sampling variability and invasiveness limit its use. We aimed to assess single breath-hold multiecho magnetic resonance imaging (MRI) for the simultaneous lipid and iron quantification in patients with hyperferritinemia.

MATERIAL AND METHODS

We compared MRI results for both iron and fat with their respective gold standards - liver iron concentration and computer-assisted image analysis for steatosis on biopsy. We prospectively studied 67 patients with hyperferritinemia and other 10 consecutive patients were used for validation. We estimated two linear calibration equations for the prediction of iron and fat based on MRI. The agreement between MRI and biopsy was evaluated.

RESULTS

MRI showed good performances in both the training and validation samples. MRI information was almost completely in line with that obtained from liver biopsy.

CONCLUSION

Single breath-hold multiecho MRI is an accurate method to obtain a valuable measure of both liver iron and steatosis in patients with hyperferritinemia.

Noninvasive Assessment of Fibrosis in Patients with Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is prevalent in 20-25% of the general population and is associated with metabolic risk factors such as obesity, diabetes mellitus, and dyslipidemia. Histologically, NAFLD ranges from simple steatosis to nonalcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. As NASH develops in only 10-15% of patients with NAFLD, it is not practical to biopsy all patients who present with NAFLD. Noninvasive fibrosis tests have been extensively developed recently and offer alternatives for staging fibrosis. Despite their increasing use, such tests cannot adequately differentiate simple steatosis from NASH. At present, such tests can be used as first line tests to rule out patients without advanced fibrosis and thus prevent unnecessary secondary care referrals in a significant number of patients. In this review we present the evidence for the use of noninvasive fibrosis tests in patients with NAFLD.

Alimentary regimen in non-alcoholic fatty liver disease: Mediterranean diet

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. The mechanisms of the underlying disease development and progression are awaiting clarification. Insulin resistance and obesity-related inflammation status, among other possible genetic, dietary, and lifestyle factors, are thought to play the key role. There is no consensus concerning the pharmacological treatment. However, the dietary nutritional management to achieve weight loss is an essential component of any treatment strategy. On the basis of its components, the literature reports on the effectiveness of the Mediterranean diet in reducing cardiovascular risk and in preventing major chronic diseases, including obesity and diabetes. New evidence supports the idea that the Mediterranean diet, associated with physical activity and cognitive behaviour therapy, may have an important role in the prevention and the treatment of NAFLD.

Serum ferritin is an important inflammatory disease marker, as it is mainly a leakage product from damaged cells

"Serum ferritin" presents a paradox, as the iron storage protein ferritin is not synthesised in serum yet is to be found there. Serum ferritin is also a well known inflammatory marker, but it is unclear whether serum ferritin reflects or causes inflammation, or whether it is involved in an inflammatory cycle. We argue here that serum ferritin arises from damaged cells, and is thus a marker of cellular damage. The protein in serum ferritin is considered benign, but it has lost (i.e. dumped) most of its normal complement of iron which when unliganded is highly toxic. The facts that serum ferritin levels can correlate with both disease and with body iron stores are thus expected on simple chemical kinetic grounds. Serum ferritin levels also correlate with other phenotypic readouts such as erythrocyte morphology. Overall, this systems approach serves to explain a number of apparent paradoxes of serum ferritin, including (i) why it correlates with biomarkers of cell damage, (ii) why it correlates with biomarkers of hydroxyl radical formation (and oxidative stress) and (iii) therefore why it correlates with the presence and/or severity of numerous diseases. This leads to suggestions for how one might exploit the corollaries of the recognition that serum ferritin levels mainly represent a consequence of cell stress and damage.

Elevated serum ferritin level is associated with the incident type 2 diabetes in healthy Korean men: a 4 year longitudinal study

Background

Elevated ferritin concentration has been implicated in the etiology of type 2 diabetes. Accumulating evidence, mostly from studies conducted on western populations, has demonstrated a strong association between the elevated ferritin concentrations and incident type 2 diabetes. In Asian populations, however, the longitudinal studies investigating the association of elevated serum ferritin levels and type 2 diabetes are lacking. In present study, we aimed to determine whether elevated serum ferritin levels are related to the incident type 2 diabetes in healthy Korean men.

Methodology/Principal Findings

This 4 year longitudinal observational study was conducted at the Asan Medical Center, Seoul, Republic of Korea. The study population consisted of 2,029 men without type 2 diabetes who underwent routine health examination in 2007 (baseline) and 2011 (follow-up). Baseline serum ferritin concentrations were measured by chemiluminescent two-site sandwich immunoassay. In multiple-adjusted model, the relative risk (RR) for incident type 2 diabetes was significantly higher in highest compared with the lowest ferritin quartile category, even after adjusting for confounding variables including homeostasis model assessment of insulin resistance (RR = 2.17, 95% confidence interval 1.27–3.72, P for trend = 0.013).

Conclusions/Significance

These results demonstrated that elevated level of serum ferritin at baseline was associated with incident type 2 diabetes in an Asian population.

High Fat Diet Induces Liver Steatosis and Early Dysregulation of Iron Metabolism in Rats

This paper is dedicated to the memory of our wonderful colleague Professor Alfredo Colonna, who passed away the same day of its acceptance. Fatty liver accumulation, inflammatory process and insulin resistance appear to be crucial in non-alcoholic fatty liver disease (NAFLD), nevertheless emerging findings pointed an important role also for iron overload. Here, we investigate the molecular mechanisms of hepatic iron metabolism in the onset of steatosis to understand whether its impairment could be an early event of liver inflammatory injury. Rats were fed with control diet or high fat diet (HFD) for 5 or 8 weeks, after which liver morphology, serum lipid profile, transaminases levels and hepatic iron content (HIC), were evaluated. In liver of HFD fed animals an increased time-dependent activity of iron regulatory protein 1 (IRP1) was evidenced, associated with the increase in transferrin receptor-1 (TfR1) expression and ferritin down-regulation. Moreover, ferroportin (FPN-1), the main protein involved in iron export, was down-regulated accordingly with hepcidin increase. These findings were indicative of an increased iron content into hepatocytes, which leads to an increase of harmful free-iron also related to the reduction of hepatic ferritin content. The progressive inflammatory damage was evidenced by the increase of hepatic TNF-α, IL-6 and leptin, in parallel to increased iron content and oxidative stress. The major finding that emerged of this study is the impairment of iron homeostasis in the ongoing and sustaining of liver steatosis, suggesting a strong link between iron metabolism unbalance, inflammatory damage and progression of disease.

Molecular diagnosis of hemochromatosis

INTRODUCTION

The discovery of hemochromatosis genes and the availability of molecular-genetic tests considerably modified the knowledge of the disease relative to physiopathology, penetrance, and expression, and had major impact in the diagnostic settings.

AREAS COVERED

Hemochromatosis is a heterogenous disorder at both genetic and phenotypic level. The review discusses criteria to define patients' iron phenotype and to use molecular tests to diagnose HFE-related and non-HFE hemochromatosis. The material examined includes articles published in the journals covered by PubMed US National Library of Medicine. The author has been working in the field of iron overload diseases for several years and has contributed 18 of the papers cited in the references.

EXPERT OPINION

Hemochromatosis genotyping is inseparable from phenotype characterization. A full clinical assessment is needed and DNA test performed when data suggest a clear indication of suspicion of being at risk for HH. HFE testing for p.Cys282Tyr mutation and p.His63Asp variant is the first molecular diagnostic step. Genotyping for rare mutations can be offered to patients with negative first-level HFE testing who have iron overload with no other explanation and should be performed in referral centers for iron overload disorders that can provide genetic advice and in-house genotyping services.

Hepcidin expression in iron overload diseases is variably modulated by circulating factors

Hepcidin is a regulatory hormone that plays a major role in controlling body iron homeostasis. Circulating factors (holotransferrin, cytokines, erythroid regulators) might variably contribute to hepcidin modulation in different pathological conditions. There are few studies analysing the relationship between hepcidin transcript and related protein expression profiles in humans. Our aims were: a. to measure hepcidin expression at either hepatic, serum and urinary level in three paradigmatic iron overload conditions (hemochromatosis, thalassemia and dysmetabolic iron overload syndrome) and in controls; b. to measure mRNA hepcidin expression in two different hepatic cell lines (HepG2 and Huh-7) exposed to patients and controls sera to assess whether circulating factors could influence hepcidin transcription in different pathological conditions. Our findings suggest that hepcidin assays reflect hepatic hepcidin production, but also indicate that correlation is not ideal, likely due to methodological limits and to several post-trascriptional events. In vitro study showed that THAL sera down-regulated, HFE-HH and C-NAFLD sera up-regulated hepcidin synthesis. HAMP mRNA expression in Huh-7 cells exposed to sera form C-Donors, HFE-HH and THAL reproduced, at lower level, the results observed in HepG2, suggesting the important but not critical role of HFE in hepcidin regulation.

Association of serum ferritin with metabolic syndrome and diabetes mellitus in the South Korean general population according to the Korean National Health and Nutrition Examination Survey 2008

We examined the association of serum ferritin levels with metabolic syndrome (MS) and diabetes mellitus in a representative sample of the adult South Korean population using data from the 2008 Korean National Health and Nutrition Examination Survey. We conducted a cross-sectional study of 6311 adults older than 20 years who participated in the 2008 Korean National Health and Nutrition Examination Survey. Metabolic syndrome was defined as the presence of at least 3 of the following: elevated blood pressure, low high-density lipoprotein cholesterol, elevated serum triglycerides, elevated plasma glucose, and abdominal obesity. Diabetes mellitus was defined as fasting glucose of at least 126 mg/dL. Insulin resistance was determined using the homeostasis model assessment estimate of insulin resistance. In a representative sample of the adult Korean population, MS was more prevalent in the highest quartile compared with the lowest quartile of serum ferritin concentrations in women following adjustments for age, education, smoking, alcohol intake, body mass index, aspartate aminotransferase, and alanine aminotransferase. Diabetes mellitus was more prevalent in the highest quartile compared with the lowest quartile of serum ferritin concentrations in premenopausal women and men. The geometric means of fasting insulin and insulin resistance determined using the homeostasis model assessment of insulin resistance in the fourth serum ferritin quartiles of postmenopausal women and men were significantly higher compared with those in the first quartile of the respective groups. The present study demonstrates that elevated serum ferritin concentrations are associated with an increased risk of MS and diabetes mellitus in a representative sample of the adult South Korean population.

Early interplay of intra-hepatic iron and insulin resistance in children with non-alcoholic fatty liver disease

BACKGROUND & AIMS

The liver is a crucial organ at the crossroads of iron and glucose metabolism. The aim of the study was to assess intra-hepatic iron in young patients with non-alcoholic fatty liver disease (NAFLD) and its association with insulin resistance and severity of liver damage.

METHODS

Intrahepatic iron content was assessed (Pearl's stain grade) in 66 patients (41 males, age 3.3-17.6years) with biopsy-proven NAFLD. Mutations of the Hereditary Hemochromatosis (HFE) gene were determined by sequence allele-specific polymerase chain reaction. Insulin resistance was estimated by means of the Oral Glucose Tolerance Test and the Insulin Sensitivity Index (ISI); the Insulino-Genic Index was also calculated. Tumor necrosis factor-alpha and interleukin-6 were measured.

RESULTS

Low-mild intra-hepatic iron deposition was observed in one out of five children (n=15, 22%), and it was not associated with HFE mutations, carried by 17 patients (26%). Among carriers of HFE mutations, four had siderosis. No abnormalities were observed in systemic indices of iron balance. Serum ferritin was within normal adult ranges in all patients (33.6±7.6ng/ml), but it was correlated with ISI (r(o)=-0.361; p=0.003). No significant difference was observed in insulin sensitivity, iron balance, inflammatory milieu, and liver histology between patients with and without hepatic siderosis.

CONCLUSIONS

In young obese individuals with NAFLD, despite normal peripheral iron parameters, mild intra-hepatic iron deposition is a frequent finding, but it is not associated with insulin resistance or severity of liver damage. Longitudinal studies are required to define the long-term relevance of these findings.

Hepcidin response to acute iron intake and chronic iron loading in dysmetabolic iron overload syndrome

BACKGROUND

The pathogenesis of dysmetabolic iron overload syndrome (DIOS) is still unclear. Hepcidin is the key regulator of iron homeostasis controlling iron absorption and macrophage release.

AIM

To investigate hepcidin regulation by iron in DIOS.

METHODS

We analysed urinary hepcidin at baseline and 24 h after a 65 mg oral iron dose in 24 patients at diagnosis and after iron depletion (n = 13) and compared data with those previously observed in 23 healthy controls. Serum iron indices, liver histology and metabolic data were available for all patients.

RESULTS

At diagnosis, hepcidin values were significantly higher than in controls (P < 0.001). After iron depletion, hepcidin levels decreased to normal values in all patients. At baseline, a significant response of hepcidin to iron challenge was observed only in the subgroup with lower basal hepcidin concentration (P = 0.007). In iron-depleted patients, urinary hepcidin significantly increased after oral iron test (P = 0 .006).

CONCLUSIONS

Ours findings suggest that in DIOS, the progression of iron accumulation is counteracted by the increase in hepcidin production and progressive reduction of iron absorption, explaining why these patients develop a mild-moderate iron overload that tends to a plateau.

Prevalence of and risk factors for hepatic steatosis and nonalcoholic Fatty liver disease in people with type 2 diabetes: the Edinburgh Type 2 Diabetes Study

OBJECTIVE

Type 2 diabetes is an established risk factor for development of hepatic steatosis and nonalcoholic fatty liver disease (NAFLD). We aimed to determine the prevalence and clinical correlates of these conditions in a large cohort of people with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 939 participants, aged 61-76 years, from the Edinburgh Type 2 Diabetes Study (ET2DS)-a large, randomly selected population of people with type 2 diabetes-underwent liver ultrasonography. Ultrasound gradings of steatosis were compared with magnetic resonance spectroscopy in a subgroup. NAFLD was defined as hepatic steatosis in the absence of a secondary cause (screened by questionnaire assessing alcohol and hepatotoxic medication use, plasma hepatitis serology, autoantibodies and ferritin, and record linkage to determine prior diagnoses of liver disease). Binary logistic regression was used to analyze independent associations of characteristics with NAFLD.

RESULTS

Hepatic steatosis was present in 56.9% of participants. After excluding those with a secondary cause for steatosis, the prevalence of NAFLD in the study population was 42.6%. Independent predictors of NAFLD were BMI, lesser duration of diabetes, HbA(1c), triglycerides, and metformin use. These remained unchanged after exclusion of participants with evidence of hepatic fibrosis from the group with no hepatic steatosis.

CONCLUSIONS

Prevalences of hepatic steatosis and NAFLD were high in this unselected population of older people with type 2 diabetes, but lower than in studies in which ultrasound gradings were not compared with a gold standard. Associations with features of the metabolic syndrome could be used to target screening for this condition.

Association of elevated serum ferritin concentration with insulin resistance and impaired glucose metabolism in Korean men and women

Increased serum ferritin concentrations in nonpathologic conditions, reflecting subclinical iron overload, have been reported to be associated with insulin resistance and an increased risk of type 2 diabetes mellitus (DM). However, serum ferritin concentrations differ significantly according to sex and ethnicity; and data concerning the relationship between serum ferritin concentrations and glucose metabolism abnormalities in Asian men and women are conflicting. This cross-sectional study investigated the association of serum ferritin concentrations with insulin resistance and impaired glucose metabolism in a large number of subjects with normal fasting glucose (NFG) level, impaired fasting glucose (IFG) level, or type 2 DM. We analyzed clinical and laboratory data from 12 090 subjects (6378 men and 5712 women; age, 20-89 years) who underwent general medical checkups. The study population included 1054 subjects with type 2 DM, 3783 subjects with IFG level, and 7253 subjects with NFG level. Serum ferritin, hemoglobin A(1c), fasting glucose, lipid, and insulin levels were measured. Insulin resistance and β-cell function indices were derived from a homeostasis model assessment. Serum ferritin concentrations were highest in the DM group, followed by the IFG group and the NFG group, in both men and women (186 ± 127, 176 ± 108, and 156 ± 92 ng/mL, respectively, in men; 85 ± 62, 75 ± 55, and 59 ± 47 ng/mL, respectively, in women). After adjustment for other variables using multiple regression analysis, homeostasis model assessment of insulin resistance was independently associated with serum ferritin concentration in men, but not in women. When the fourth quartile of ferritin was compared with the first quartile, the age-adjusted odds ratio (OR) for type 2 DM was 1.71 (95% confidence interval, 1.38-2.12) in men and 1.50 (1.05-2.13) in women. The OR in men was attenuated to 1.27 (1.01-1.60) but remained significant after adjustment for body mass index (BMI), waist circumference, blood pressure, serum lipids, liver enzymes, and high-sensitivity C-reactive protein (hsCRP). In nondiabetic subjects, the age-adjusted OR for IFG in the fourth quartile of ferritin was 1.82 (1.56-2.13) in men and 1.68 (1.40-2.02) in women. The OR was attenuated to 1.31 (1.11-1.55) in men and 1.45 (1.19-1.78) in women after adjustment for BMI, waist circumference, blood pressure, serum lipids, liver enzymes, and hsCRP. In NFG subjects, the age-adjusted OR for metabolic syndrome in the fourth quartile of ferritin concentration was 2.85 (1.99-4.07) in men and 1.21 (0.82-1.79) in women. In men, the OR was attenuated to 1.58 (1.06-2.37) after adjustment for BMI, liver enzymes, and hsCRP. Increased serum concentrations of ferritin are associated with insulin resistance, type 2 DM, IFG, and metabolic syndrome in men, but only with IFG in women. These results suggest that iron overload is associated with insulin resistance in men, but not in women.

Characteristics of patients with sulphonurea-induced hypoglycemia

BACKGROUND/AIM

Sulphonylurea (SU) agents continue to be a cornerstone of the therapy of type 2 diabetes mellitus (T2DM). Hypoglycemia is the most dangerous side effect of SU. Identifying the characteristics of patients with SU-induced hypoglycemia (SUIH) may help in reducing its frequency.

METHODS

All consecutive admissions of patients with SUIH, between 2000 and 2008, were retrospectively reviewed.

RESULTS

Over the study period, 4702 patients with type 2 diabetes mellitus were admitted to the department of medicine. Of these, 155 patients were admitted because of SUIH. Most of these patients were elderly, had multiple comorbid situations, and were taking multiple medications. Almost a third of the patients had a history of recent changes in the use of their medications. Various infectious complications (urinary, lung, skin, and peritoneal) occurred in 43% of patients. Renal failure was a frequent finding at admission (44% of patients had creatinine plasma levels > 120 μmol/L). Poor oral intake before admission was reported by 31% of patients. Markers of malnutrition (low serum levels of albumin, iron, vitamin B-12, and folic acid) were frequently found in most patients. Mean hemoglobin A1C levels were in the low abnormal levels. A major vascular event during hospitalization co-occurred in 11% of patients. Three patients died during the hospital admission for SUIH.

CONCLUSIONS

Elderly fragile patients with multiple comorbid situations including renal failure and tight glycemic control are prone to develop SUIH. Sulphonylurea agents should be avoided in such patients. An episode of SUIH should be considered as an alarming prognostic marker.

Frequency and risk factors associated with non-alcoholic fatty liver disease in patients with type 2 diabetes mellitus

OBJECTIVE

To evaluate the frequency of non-alcoholic fatty liver disease (NAFLD) in patients with type 2 diabetes mellitus (DM2) and to describe its risk factors.

SUBJECTS AND METHODS

Blood samples of 78 patients were collected for assessment of glycemic and lipid profile, liver enzymes, TNF-alpha and HOMA-IR. The diagnosis of NAFLD was established by ultrasound.

RESULTS

NAFLD was observed in 42% of patients who had greater BMI (p < 0.001), and frequency of hypertension (p < 0.001). Metabolic syndrome was more frequent in those with NAFLD (p = 0.019). The levels of aspartate, alanine aminotransferase, gamma-glutamyl transpeptidase, uric acid, TNF-alpha, insulin and HOMA-IR were significantly higher in patients with NAFLD than those without NAFLD.

CONCLUSION

Almost half of patients with DM2 were found to have NAFLD, and they have more elevated BMI, as well as higher levels of aminotransferases, gamma-GT, uric acid, TNF-alpha, insulin and HOMA-IR than subjects without NAFLD.

Nonalcoholic fatty liver disease and HFE gene mutations: A Polish study

AIM: To describe a Polish population with nonalcoholic fatty liver disease (NAFLD) with regard to HFE gene mutations, as well as analyzing demographic and clinical data.

METHODS: Sixty-two consecutive patients with biopsy-proven NAFLD were included in the study. Demographic, clinical, and laboratory data were summarized in a database. C282Y and H63D mutations of the HFE gene were analyzed using polymerase chain reaction-restriction fragment lenght polymorphism.

RESULTS: The analyzed cohort consisted of 62 homogeneic Caucasian participants, 66.1% men and 33.9% women, with a median age of 48 years. The median body mass index was 29.05 kg/m². Hypercholesterolemia was observed in 74.2% of patients and hypertriglyceridemia in 32.2%; 16.1% had type 2 diabetes mellitus (DMt2). On liver biopsy, 22.6% of NAFLD patients were found to have severe fibrosis. There were no differences between frequencies of HFE gene mutations in subgroups of NAFLD patients with less and more severe liver fibrosis. Obesity, older age, female gender and DMt2 were associated with more advanced fibrosis in this Polish cohort, as well as higher glucose level, serum iron and transaminase aspartate aminotransferase/alanine aminotransferase ratio.

CONCLUSION: HFE mutations conferred no additional hepatic fibrosis risk in NAFLD, but higher serum iron was a risk factor for severe liver damage in NAFLD, regardless of HFE mutations.

Serum apoptotic caspase activity in chronic hepatitis C and nonalcoholic Fatty liver disease

BACKGROUND

Apoptotic caspases are substantially activated in liver and serum caspase activity has been suggested as a marker of early liver injury.

AIM

To investigate whether serum levels of caspase-generated fragments of cytokeratin-18 are associated with the severity of histologic lesions in chronic hepatitis C virus (HCV) infection and nonalcoholic fatty liver disease (NAFLD).

METHODS

We included 134 patients with chronic HCV infection and 58 patients with NAFLD, who consecutively underwent liver biopsy, and 40 healthy controls. Caspase-generated cytokeratin-18 fragment levels were blindly measured in stored serum samples.

RESULTS

Median cytokeratin-18 fragment levels were lower in HCV-positive patients with minimal/mild than patients with moderate/severe histologic lesions (174 U/L vs. 223 U/L, P<0.001) offering moderate accuracy for differentiation between the 2 groups (c-statistic: 0.74). Cytokeratin-18 fragments levels were lower in healthy subjects (148 U/L) than patients with simple fatty liver (174 U/L, P=0.013) than patients with nonalcoholic steatohepatitis (355 U/L, P<0.001) offering excellent diagnostic accuracy for differentiation between the 2 latter groups (c-statistic: 0.87).

CONCLUSIONS

Serum apoptotic caspase activity is associated with the severity of liver histologic lesions in both chronic HCV infection and NAFLD, but it has excellent diagnostic accuracy in NAFLD and moderate accuracy in chronic HCV patients.

Serum ferritin is a major determinant of lipid phenotype in familial combined hyperlipidemia and familial hypertriglyceridemia

Familial combined hyperlipidemia (FCH) and familial hypertriglyceridemia (FHTG) share pathogenic mechanisms and a high interaction with components of the metabolic syndrome. The metabolic syndrome associates increased serum ferritin concentration and high cardiovascular risk. The objective was to describe the frequency of iron overload and the relationship between serum ferritin and the phenotype in patients with FCH and FHTG. The study was composed of 211 consecutive unrelated patients aged at least 18 years with primary hypertriglyceridemia, 149 with FCH, and 62 with FHTG. The prevalence of the metabolic syndrome and hyperferritinemia was very high in both hypertriglyceridemic groups (51.7% and 20.1% in FCH and 62.9% and 16.1% in FHTG, respectively), without significant statistical differences between them. Serum ferritin concentration did not show any significant association with the number of metabolic syndrome criteria. Subjects in the highest tertile of ferritin concentration (ferritin >200 mug/L) presented higher concentrations of triglycerides and liver enzymes than subjects in the first tertile of ferritin concentration (ferritin <90 mug/L). The highest positive correlation coefficient for triglycerides was found with ferritin in FCH and in FHTG subjects (R = 0.317 [P < .001] when combined). Ferritin was also the covariate that showed the highest independent association with triglycerides in FCH and FHTG. In contrast, ferritin was not associated with carotid intima-media thickness. In summary, serum ferritin is commonly increased in FCH and in FHTG, it is not related with the presence of metabolic syndrome, and it is highly correlated with liver enzymes.

Hyperferritinemia is a risk factor for steatosis in chronic liver disease

AIM

To investigate the relationship between ferritin and steatosis in patients with chronically abnormal liver function tests (LFTs) and high ferritin level.

METHODS

One hundred and twenty-four consecutive patients with hyperferritinemia (male > 300 ng/mL, female > 200 ng/mL) were evaluated; clinical, biochemical and serological data, iron status parameters, HFE gene mutations and homeostasis model assessment score were obtained. Steatosis was graded by ultrasound as absent or present. Histology was available in 53 patients only.

RESULTS

Mean level of ferritin was 881 +/- 77 ng/mL in men and 549 +/- 82 ng/mL in women. The diagnosis was chronic hepatitis C in 53 (42.7%), non-alcoholic fatty liver disease/non-alcoholic steatohepatitis in 57 (45.9%), and cryptogenic liver damage in 14 (11.3%). None was diagnosed as hereditary hemochromatosis (HH). Hepatic siderosis on liver biopsy was present in 17 of 54 (32%) patients; grade 1 in eight and grade 2 in nine. Overall, 92 patients (74.2%) had steatosis. By logistic regression, ferritin and gamma-glutamyltransferase were independent predictors of steatosis. Ferritin levels were significantly related to low platelet count, steatosis and hepatitis C virus infection.

CONCLUSION

In a non-obese cohort of non-alcoholic patients with chronically abnormal LFTs without HH, high serum ferritin level is a risk factor for steatosis.

Glucose abnormalities in non-alcoholic fatty liver disease and chronic hepatitis C virus infection: the role of iron overload

Non-alcoholic fatty liver disease (NAFLD) and chronic hepatitis C virus (HCV) infection are major causes of liver disease frequently described in outpatient patients with glucose abnormalities. Hyperferritinemia, which suggests that iron overload plays a decisive role in the pathophysiology of insulin resistance and hyperglycemia, is a common finding in both disorders. However, the role of the hepatic iron deposition differs from one to the other. In NAFLD, a moderate liver iron accumulation has been observed and molecular mechanisms, including the downregulation of the liver iron exporter ferroportin-1, have been described. Iron overload will enhance intrahepatic oxidative stress that promotes hepatic fibrosis, interfere with insulin signalling at various levels and may hamper hepatic insulin extraction. Therefore, liver fibrosis, hyperglycemia and hyperinsulinemia will lead to increased levels of insulin resistance and the development of glucose abnormalities. Furthermore, iron depletion by phlebotomy removes liver iron content and reduces serum glucose and insulin resistance in NAFLD patients. Therefore, it seems that iron overload participates in those glucose abnormalities associated with NAFLD. Concerning chronic HCV infection, it has been classically assumed that iron overload contributes to insulin resistance associated with virus infection. However, recent evidence argues against the presence of iron overload in these patients and points to inflammation associated with diabetes as the main contributor to the elevated ferritin levels. Therefore, glucose abnormalities, and specially type 2 diabetes, should be taken into account when evaluating serum ferritin levels in patients with HCV infection.

Hyperferritinemia is a risk factor for steatosis in chronic liver disease

AIM: To investigate the relationship between ferritin and steatosis in patients with chronically abnormal liver function tests (LFTs) and high ferritin level.

METHODS: One hundred and twenty-four consecutive patients with hyperferritinemia (male > 300 ng/mL, female > 200 ng/mL) were evaluated; clinical, biochemical and serological data, iron status parameters, HFE gene mutations and homeostasis model assessment score were obtained. Steatosis was graded by ultrasound as absent or present. Histology was available in 53 patients only.

RESULTS: Mean level of ferritin was 881 ± 77 ng/mL in men and 549 ± 82 ng/mL in women. The diagnosis was chronic hepatitis C in 53 (42.7%), non-alcoholic fatty liver disease/non-alcoholic steatohepatitis in 57 (45.9%), and cryptogenic liver damage in 14 (11.3%). None was diagnosed as hereditary hemochromatosis (HH). Hepatic siderosis on liver biopsy was present in 17 of 54 (32%) patients; grade 1 in eight and grade 2 in nine. Overall, 92 patients (74.2%) had steatosis. By logistic regression, ferritin and γ-glutamyltransferase were independent predictors of steatosis. Ferritin levels were significantly related to low platelet count, steatosis and hepatitis C virus infection.

CONCLUSION: In a non-obese cohort of non-alcoholic patients with chronically abnormal LFTs without HH, high serum ferritin level is a risk factor for steatosis.

Revaluation of clinical and histological criteria for diagnosis of dysmetabolic iron overload syndrome

AIM: To re-evaluate the diagnostic criteria of insulin resistance hepatic iron overload based on clinical, biochemical and histopathological findings.

METHODS: We studied 81 patients with hepatic iron overload not explained by known genetic and acquired causes. The metabolic syndrome (MS) was defined according to ATPIII criteria. Iron overload was assessed by liver biopsy. Liver histology was evaluated by Ishak’s score and iron accumulation by Deugnier’s score; steatosis was diagnosed when present in ≥ 5% of hepatocytes.

RESULTS: According to transferrin saturation levels, we observed significant differences in the amount of hepatic iron overload and iron distribution, as well as the number of metabolic abnormalities. Using Receiving Operating Curve analysis, we found that the presence of two components of the MS differentiated two groups with a statistically significant different hepatic iron overload (P < 0.0001). Patients with ≥ 2 metabolic alterations and steatosis had lower amount of hepatic iron, lower transferrin saturation and higher sinusoidal iron than patients with < 2 MS components and absence of steatosis.

CONCLUSION: In our patients, the presence of ≥ 2 alterations of the MS and hepatic steatosis was associated with a moderate form of iron overload with a prevalent sinusoidal distribution and a normal transferrin saturation, suggesting the existence of a peculiar pathogenetic mechanism of iron accumulation. These patients may have the typical dysmetabolic iron overload syndrome. By contrast, patients with transferrin saturation ≥ 60% had more severe iron overload, few or no metabolic abnormalities and a hemochromatosis-like pattern of iron overload.

A preliminary investigation of the association between haptoglobin polymorphism, serum ferritin concentration and fatty liver disease

BACKGROUND

The genetic polymorphism of haptoglobin (HP) has been associated with cardiovascular disease and type 2 diabetes. We hypothesized that the HP polymorphism could affect the incidence of nonalcoholic fatty liver disease (NAFLD).

METHODS

This cross sectional case-control analysis included 337 Japanese participants in a health screening program. Fatty liver disease (FLD) was diagnosed by ultrasonography scanning and was classified into NAFLD based on the daily alcohol intake. The HP1 and HP2 alleles were determined using the PCR, and serum ferretin concentrations were measured.

RESULTS

FLD and NAFLD were diagnosed in 91 and 69 subjects, respectively. The adjusted odd ratio (OR) of HP2 carriers vs. non-carriers was 11.8 [95% confidence intervals (CI), 1.3-104.0] for FLD, and 11.7 (95% CI, 1.3-107.9) for NAFLD. Male FLD cases with the HP2/HP2genotype had significantly higher ferretin concentrations than those without (P=0.003). The ferritin concentrations were correlated with the alanine-aminotransferase activities (r=0.48, P<0.001 in FLD cases with the HP2/HP2 genotype). Ferritin was an independent risk factor for FLD, and the incidence of FLD significantly increased in association with ferritin.

CONCLUSIONS

This is a preliminary but the first report suggesting the HP2 allele to be a candidate risk factor for NAFLD.

Hepcidin and iron-related gene expression in subjects with Dysmetabolic Hepatic Iron Overload

BACKGROUND/AIMS

Many patients with hepatic iron overload do not have identifiable mutations and often present with metabolic disorders and hepatic steatosis. Since the pathophysiology of Dysmetabolic Hepatic Iron Overload (DHIO) is still obscure, the aim of this study was to evaluate, in these patients, possible alterations in iron-related molecule expression.

METHODS

Iron-related gene mRNA levels were determined by quantitative-PCR in liver biopsies of subjects with NAFLD without iron overload and patients with HFE-hemochromatosis, beta-thalassemia major and DHIO. Urinary hepcidin was measured by immunoblotting.

RESULTS

No alterations in mRNA expression of either iron transporters or exporters were found in DHIO. mRNA and urinary hepcidin levels normalized for the amount of iron overload showed a significantly lower ratio than in controls, although not as low as in hemochromatosis or beta-thalassemia. Differently from what observed in hemochromatosis, hepcidin mRNA did not correlate with urinary hepcidin.

CONCLUSIONS

Patients with DHIO show appropriate regulation of mRNAs encoding proteins involved in iron uptake and efflux but dysregulation of hepcidin production. The relatively elevated urinary hepcidin can explain the iron phenotype in DHIO (more macrophage iron retention and low/normal transferrin saturation).

Non-alcoholic fatty liver disease: the mist gradually clears

Non-alcoholic fatty liver disease (NAFLD) is now the commonest liver disorder in the developed world affecting up to a third of individuals. It is closely associated with features of the metabolic syndrome, particularly obesity and diabetes. It can progress to cirrhosis, hepatocellular carcinoma and liver failure and is an increasing indication for transplantation. Dietary and genetic factors determine susceptibility to NAFLD and its progression. NAFLD may also be involved in the pathogenesis of cardiovascular disease. Most patients present with incidentally found abnormal liver blood tests. Diagnosis is usually one of exclusion. Liver biopsy is required for disease staging, but new imaging modalities and biomarkers are emerging which may eventually fulfil this role. There is, as yet no firm evidence-based treatment for NAFLD. Therapy is currently directed at treating components of the metabolic syndrome which may also be beneficial for the liver. The recent elucidation of the mechanisms leading to progressive disease suggests a variety of novel targets worthy of testing in animal models of NAFLD and subsequently in pilot studies in humans.