Hepatic steatosis: A benign disease or a silent killer

What are the common downstream molecular events between alcoholic and nonalcoholic fatty liver?

Liver fat storage, also called hepatic steatosis, is increasingly common and represents a very frequent diagnosis in the medical field. Excess fat is not without consequences. In fact, hepatic steatosis contributes to the progression toward liver fibrosis. There are two main types of fatty liver disease, alcoholic fatty liver disease (AFLD) and nonalcoholic fatty liver disease (NAFLD). Although AFLD and NAFLD are similar in their initial morphological features, both conditions involve the same evolutive forms. Moreover, there are various common mechanisms underlying both diseases, including alcoholic liver disease and NAFLD, which are commonalities. In this Review, the authors explore similar downstream signaling events involved in the onset and progression of the two entities but not completely different entities, predominantly focusing on the gut microbiome. Downstream molecular events, such as the roles of sirtuins, cytokeratins, adipokines and others, should be considered. Finally, to complete the feature, some new tendencies in the therapeutic approach are presented.

Crosstalk between autophagy and insulin resistance: evidence from different tissues

Insulin is a critical hormone that promotes energy storage in various tissues, as well as anabolic functions. Insulin resistance significantly reduces these responses, resulting in pathological conditions, such as obesity and type 2 diabetes mellitus (T2DM). The management of insulin resistance requires better knowledge of its pathophysiological mechanisms to prevent secondary complications, such as cardiovascular diseases (CVDs). Recent evidence regarding the etiological mechanisms behind insulin resistance emphasizes the role of energy imbalance and neurohormonal dysregulation, both of which are closely regulated by autophagy. Autophagy is a conserved process that maintains homeostasis in cells. Accordingly, autophagy abnormalities have been linked to a variety of metabolic disorders, including insulin resistance, T2DM, obesity, and CVDs. Thus, there may be a link between autophagy and insulin resistance. Therefore, the interaction between autophagy and insulin function will be examined in this review, particularly in insulin-responsive tissues, such as adipose tissue, liver, and skeletal muscle.

Polarity-Sensitive Probe for Two-Photon Fluorescence Lifetime Imaging of Lipid Droplets In Vitro and In Vivo

Lipid droplets (LDs) are crucial organelles used to store lipids and participate in lipid metabolism in cells. The abnormal aggregation and polarity change of LDs are associated with the occurrence of diseases, such as steatosis. Herein, the polarity-sensitive probe TBPCPP with a donor-acceptor-π-acceptor (D-A-π-A) structure was designed and synthesized. The TBPCPP has a large Stokes shift (∼220 nm), excellent photostability, high LD targeting, and considerable two-photon absorption (TPA) cross-section (∼226 GM), enabling deep two-photon imaging (∼360 μm). In addition, the fluorescence lifetime of TBPCPP decreases linearly with increasing solvent polarity. Therefore, with the assistance of two-photon fluorescence lifetime imaging microscopy (TP-FLIM), TBPCPP has successfully achieved not only the visualization of polarity changes caused by LD accumulation in HepG-2 cells but also lipid-specific imaging and visualization of different polarities in lipid-rich regions in zebrafish for the first time. Furthermore, TP-FLIM revealed that the polarity gradually decreases during steatosis in HepG-2 cells, which provided new insights into the diagnosis of steatosis.

Type 2 Diabetes Mellitus and Liver Disease: Across the Gut-Liver Axis from Fibrosis to Cancer

Type 2 diabetes mellitus is a widespread disease worldwide, and is one of the cornerstones of metabolic syndrome. The existence of a strong relationship between diabetes and the progression of liver fibrosis has been demonstrated by several studies, using invasive and noninvasive techniques. Patients with type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD) show faster progression of fibrosis than patients without diabetes. Many confounding factors make it difficult to determine the exact mechanisms involved. What we know so far is that both liver fibrosis and T2DM are expressions of metabolic dysfunction, and we recognize similar risk factors. Interestingly, both are promoted by metabolic endotoxemia, a low-grade inflammatory condition caused by increased endotoxin levels and linked to intestinal dysbiosis and increased intestinal permeability. There is broad evidence on the role of the gut microbiota in the progression of liver disease, through both metabolic and inflammatory mechanisms. Therefore, dysbiosis that is associated with diabetes can act as a modifier of the natural evolution of NAFLD. In addition to diet, hypoglycemic drugs play an important role in this scenario, and their benefit is also the result of effects exerted in the gut. Here, we provide an overview of the mechanisms that explain why diabetic patients show a more rapid progression of liver disease up to hepatocellular carcinoma (HCC), focusing especially on those involving the gut-liver axis.

An older diabetes-induced mice model for studying skin wound healing

Advances in wound treatment depend on the availability of animal models that reflect key aspects of human wound healing physiology. To this date, the accepted mouse models do not reflect defects in the healing process for chronic wounds that are associated with type two diabetic skin ulcers. The long term, systemic physiologic stress that occurs in middle aged or older Type 2 diabetes patients is difficult to simulate in preclinical animal model. We have strived to incorporate the essential elements of this stress in a manageable mouse model: long term metabolic stress from obesity to include the effects of middle age and thereafter onset of diabetes. At six-weeks age, male C57BL/6 mice were separated into groups fed a chow and High-Fat Diet for 0.5, 3, and 6 months. Treatment groups included long term, obesity stressed mice with induction of diabetes by streptozotocin at 5 months, and further physiologic evaluation at 8 months old. We show that this model results in a severe metabolic phenotype with insulin resistance and glucose intolerance associated with obesity and, more importantly, skin changes. The phenotype of this older age mouse model included a transcriptional signature of gene expression in skin that overlapped that observed with elderly patients who develop diabetic foot ulcers. We believe this unique old age phenotype contrasts with current mice models with induced diabetes.

Characterization of hepatic inflammatory changes in a C57BL/6J mouse model of alpha1-antitrypsin deficiency

Alpha-1 antitrypsin deficiency (AATD) is a genetic disease caused by a hepatic accumulation of mutant alpha-1 antitrypsin (ZAAT). Individuals with AATD are prone to develop a chronic liver disease that remains undiagnosed until late stage of the disease. Here, we sought to characterize the liver pathophysiology of a human transgenic mouse model for AATD with a manifestation of liver disease compared with normal transgenic mice model. Male and female transgenic mice for normal (Pi*M) and mutant variant (Pi*Z) human alpha-1 antitrypsin at 3 and 6 mo of age were subjected to this study. The progression of hepatic ZAAT accumulation, hepatocyte injury, steatosis, liver inflammation, and fibrotic features were monitored by performing an in vivo study. We have also performed a Next-Gene transcriptomic analysis of the transgenic mice liver tissue 16 h after lipopolysaccharide (LPS) administration to delineate liver inflammatory response in Pi*Z mice as compared with Pi*M. Our results show hepatic ZAAT accumulation, followed by hepatocyte ballooning and liver steatosis developed at 3 mo in Pi*Z mice compared with the mice carrying normal variant of human alpha-1 antitrypsin. We observed higher levels of hepatic immune cell infiltrations in both 3- and 6-mo-old Pi*Z mice compared with Pi*M as an indication of liver inflammation. Liver fibrosis was observed as accumulation of collagen in 6-mo-old Pi*Z liver tissues compared with Pi*M control mice. Furthermore, the transcriptomic analysis revealed a dysregulated liver immune response to LPS in Pi*Z mice compared with Pi*M. Of particular interest for translational work, this study aims to establish a mouse model of AATD with a strong manifestation of liver disease that will be a valuable in vivo tool to study the pathophysiology of AATD-mediated liver disease. Our data suggest that the human transgenic mouse model of AATD could provide a suitable model for the evaluation of therapeutic approaches and preventive reagents against AATD-mediated liver disease.NEW & NOTEWORTHY We have characterized a mouse model of human alpha-1 antitrypsin deficiency with a strong manifestation of liver disease that can be used as an in vivo tool to test preventive and therapeutic reagents. Our data explores the altered immunophenotype of alpha-1 antitrypsin-deficient liver macrophages and suggests a relationship between acute inflammation, immune response, and fibrosis.

Is it possible to treat nonalcoholic liver disease using a flavanol-based nutraceutical approach? Basic and clinical data

Nonalcoholic fatty liver disease (NAFLD) is characterized by a spectrum of diseases, ranging from simple steatosis to hepatocellular carcinoma. The main factors for NAFLD are closely related to obesity, insulin resistance, intestinal microbiota alterations, hyperinsulinism, low-grade systemic inflammation, nitroxidative stress, lipid peroxidation, and mitochondrial dysfunction. Currently, the treatment of NAFLD is based on diet and exercise because, to date, there is no specific pharmacological agent, already approved, that raises the need for new therapeutic strategies. Nutraceuticals, such as polyphenols, have potential beneficial effects for health. In this article, the beneficial effects of epigallocatechin-3-gallate (EGCG) and (-)-epicatechin (EC) are discussed. EGCG is the main catechin in green tea, which has shown in various studies its potential effect preventing and treating NAFLD since it has shown antihyperlipidemic, anti-inflammatory, antifibrotic, antioxidant, and improvement of liver lipid metabolism. However, it has been found that excessive consumption may cause hepatotoxicity. EC is widely distributed in nature (fruits and vegetables). This flavanol has shown many beneficial effects, including antihypertensive, anti-inflammatory, anti-hyperglycemic, antithrombotic, and antifibrotic properties. It increases mitochondrial biogenesis, and it also has effects on the regulation of synthesis and metabolism of lipids. This flavanol is a nontoxic substance; it has been classified by the United States Food and Drug Administration as harmless. The EC-induced effects can be useful for the prevention and/or treatment of NAFLD.

Uncovering the roles of dihydropyrimidine dehydrogenase in fatty-acid induced steatosis using human cellular models

Pyrimidine catabolism is implicated in hepatic steatosis. Dihydropyrimidine dehydrogenase (DPYD) is an enzyme responsible for uracil and thymine catabolism, and DPYD human genetic variability affects clinically observed toxicity following 5-Fluorouracil administration. In an in vitro model of fatty acid-induced steatosis, the pharmacologic inhibition of DPYD resulted in protection from lipid accumulation. Additionally, a gain-of-function mutation of DPYD, created through clustered regularly interspaced short palindromic repeats associated protein 9 (CRISPR-Cas9) engineering, led to an increased lipid burden, which was associated with altered mitochondrial functionality in a hepatocarcionma cell line. The studies presented herein describe a novel role for DPYD in hepatocyte metabolic regulation as a modulator of hepatic steatosis.

The CD38 glycohydrolase and the NAD sink: implications for pathological conditions

Nicotinamide adenine dinucleotide (NAD) acts as a cofactor in several oxidation-reduction (redox) reactions and is a substrate for a number of nonredox enzymes. NAD is fundamental to a variety of cellular processes including energy metabolism, cell signaling, and epigenetics. NAD homeostasis appears to be of paramount importance to health span and longevity, and its dysregulation is associated with multiple diseases. NAD metabolism is dynamic and maintained by synthesis and degradation. The enzyme CD38, one of the main NAD-consuming enzymes, is a key component of NAD homeostasis. The majority of CD38 is localized in the plasma membrane with its catalytic domain facing the extracellular environment, likely for the purpose of controlling systemic levels of NAD. Several cell types express CD38, but its expression predominates on endothelial cells and immune cells capable of infiltrating organs and tissues. Here we review potential roles of CD38 in health and disease and postulate ways in which CD38 dysregulation causes changes in NAD homeostasis and contributes to the pathophysiology of multiple conditions. Indeed, in animal models the development of infectious diseases, autoimmune disorders, fibrosis, metabolic diseases, and age-associated diseases including cancer, heart disease, and neurodegeneration are associated with altered CD38 enzymatic activity. Many of these conditions are modified in CD38-deficient mice or by blocking CD38 NADase activity. In diseases in which CD38 appears to play a role, CD38-dependent NAD decline is often a common denominator of pathophysiology. Thus, understanding dysregulation of NAD homeostasis by CD38 may open new avenues for the treatment of human diseases.

Alcoholic liver disease-from steatosis to cirrhosis - a biochemistry approach

Nowadays, chronic alcoholism and its health implications represent a global concern. Over three million deaths are linked to chronic alcohol intake every year. This article aims to spread awareness about the negative impact ethanol can have on almost every organ in the body, especially the liver. Understanding ethanol metabolism and the cellular pathways through which alcohol increases liver oxidative stress may prevent a broad spectrum of hepatic lesions such as steatosis, steatohepatitis, and, ultimately, cirrhosis. After a short review of ethanol metabolism and liver oxidative stress, each hepatic lesion will be individually discussed regarding the mechanism of apparition, treatment, and future targeted therapies.

Evaluation of NAFLD fibrosis, FIB-4 and APRI score in diabetic patients receiving exenatide treatment for non-alcoholic fatty liver disease

There is a closely relationship between the development and progression of nonalcoholic fatty liver disease (NAFLD) or metabolic associated fatty liver disease (MAFLD) and obesity and diabetes. NAFLD fibrosis scores should be routinely used to rule out patients with advanced fibrosis. High scores may help identify patients at higher risk of all causes andliverrelated morbidity and mortality. The aim of this study was to investigate the association between exenatide and fibrosis scores. The effect of exenatide treatment on fibrosis scores was evaluated in type 2 diabetes mellitus (DM) patients with MAFLD. Evaluation was made of 50 patients with type 2 DM and MAFLD. The NFS, FIB4 and APRI scores were calculated before and after 6 months of treatment. After 6 months of exenatide treatment, the NFS and APRI scores were determined to have decreased significantly. Exenatide was observed to control blood glucose, reduce body weight and improve fibrosis scores in MAFLD patients with type 2 diabetes.

Hepatoprotective and therapeutic effects of resveratrol: A focus on anti-inflammatory and anti- oxidative activities

Being the most essential organ in the body, the liver performs critical functions. Hepatic disorders, such as alcoholic liver disease, hepatic steatosis, liver fibrosis, non-alcoholic fatty liver disease, hepatocellular carcinoma and hepatic failure, have an impact on the biochemical and physiological functions of the body. The main representative of the flavonoid subgroup of flavones, Resveratrol (RES), exhibits suitable pharmacological activities for treating various liver diseases, such as fatty hepatitis, liver steatosis, liver cancer and liver fibrosis. According to various studies, grapes and red wine are good sources of RES. RES has various health properties; it is anti-inflammatory, anti-apoptotic, anti-oxidative and hepatoprotective against several hepatic diseases and hepatoxicity. Therefore, we performed a thorough research and created a summary of the distinct targets of RES in various stages of liver diseases. We concluded that RES inhibited liver inflammation essentially by causing a significant decrease in the expression of various pro-inflammatory cytokines like TNF-α, IL-1α, IL-1β, and IL-6. It also inhibits the transcription factor nuclear NF-κB that brings about the inflammatory cascade. RES also inhibits the PI3K/Akt/mTOR pathway to induce apoptosis. Additionally, it reduces oxidative stress in hepatic tissue by markedly reducing MDA and NO contents, and significantly increasing the levels of CAT, SOD and reduced GSH, in addition to AST and ALT, against toxic chemicals like CC14, As2O3 and TTA. Due to its anti-oxidant, anti-inflammatory and anti-fibrotic properties, RES reduces liver injury markers. RES is safe natural antioxidant that provides pharmacological rectification of the hepatoxicity of toxic chemicals.

Endoplasmic reticulum stress as a key mechanism in stunted growth of seawater rainbow trout (Oncorhynchus mykiss)

BACKGROUND

Rainbow trout (Oncorhynchus mykiss) is a salmonid species with a complex life-history. Wild populations are naturally divided into freshwater residents and sea-run migrants. Migrants undergo an energy-demanding adaptation for life in seawater, known as smoltification, while freshwater residents display these changes in an attenuated magnitude and rate. Despite this, in seawater rainbow trout farming all fish are transferred to seawater. Under these circumstances, weeks after seawater transfer, a significant portion of the fish die (around 10%) or experience growth stunting (GS; around 10%), which represents an important profitability and welfare issue. The underlying causes leading to GS in seawater-transferred rainbow trout remain unknown. In this study, we aimed at characterising the GS phenotype in seawater-transferred rainbow trout using untargeted and targeted approaches. To this end, the liver proteome (LC-MS/MS) and lipidome (LC-MS) of GS and fast-growing phenotypes were profiled to identify molecules and processes that are characteristic of the GS phenotype. Moreover, the transcription, abundance or activity of key proteins and hormones related to osmoregulation (Gill Na+, K + -ATPase activity), growth (plasma IGF-I, and liver igf1, igfbp1b, ghr1 and ctsl) and stress (plasma cortisol) were measured using targeted approaches.

RESULTS

No differences in Gill Na+, K + -ATPase activity and plasma cortisol were detected between the two groups. However, a significant downregulation in plasma IGF-I and liver igf1 transcription pointed at this growth factor as an important pathomechanism for GS. Changes in the liver proteome revealed reactive-oxygen-species-mediated endoplasmic reticulum stress as a key mechanism underlying the GS phenotype. From the lipidomic analysis, key observations include a reduction in triacylglycerols and elevated amounts of cardiolipins, a characteristic lipid class associated with oxidative stress, in GS phenotype.

CONCLUSION

While the triggers to the activation of endoplasmic reticulum stress are still unknown, data from this study point towards a nutritional deficiency as an underlying driver of this phenotype.

NAFLD mark: an accurate model based on microRNA-34 for diagnosis of non-alcoholic fatty liver disease patients

BACKGROUND

It remains essential for non-alcoholic fatty liver (NAFLD) patients, to develop a sensitive and specific diagnostic model. Data regarding the use of micro (mi)RNA-34 for NAFLD diagnosis are few. Routine clinical assessment, laboratory tests were done for Egyptian individuals (n = 314) were included (100 healthy individuals and 214 NAFLD patients). Quantification of miRNA-34 was done using real-time PCR. Extremely significant variables were entered into stepwise logistic regression. The diagnostic power of variables was estimated by the area under the ROC (AUC).

RESULTS

MiRNA-34 levels were higher in NAFLD patients than healthy individuals with a significant difference (P< 0.0001). The multivariate analysis was used to evaluate the NAFLD-associated variables (CRP, cholesterol, body mass index (BMI), ALT had p< 0.0001 while mRNA-34 had (p=0.0004). The AUCs (CI) of candidate NAFLD markers were in the order of miRNA-34 0.72 (0.66-0.77) < ALT 0.73 (0.67-0.79) < BMI 0.81 (0.76-0.86) < cholesterol < 0.85 (0.79-0.90) < CRP 0.88 (0.84-0.92). We developed a novel index for discriminating patients with NAFLD named NAFLD Mark. AUC was jumped to 0.98 (0.93-0.99) when five markers were combined. The AUC of NAFLD mark for NAFLD detection was higher than the AUCs of seven common NAFLD indexes (0.44-0.86).

CONCLUSIONS

The NAFLD mark is a non-invasive and highly sensitive and specific model for NAFLD diagnosis.

Profiling and targeting connective tissue remodeling in autoimmunity - A novel paradigm for diagnosing and treating chronic diseases

Connective tissue (ConT) remodeling is an essential process in tissue regeneration, where a balanced replacement of old tissue by new tissue occurs. This balance is disturbed in chronic diseases, often autoimmune diseases, usually resulting in the buld up of fibrosis and a gradual loss of organ function. During progression of liver, lung, skin, heart, joint, skeletal and kidney diseasesboth ConT formation and degradation are elevated, which is tightly linked to immune cell activation and a loss of specific cell types and extracellular matrix (ECM) structures that are required for normal organ function. Here, we address the balance of key general and organ specific components of the ECM during homeostasis and in disease, with a focus on collagens, which are emerging as both structural and signaling molecules harbouring neoepitopes and autoantigens that are released during ConT remodeling. Specific collagen molecular signatures of ConT remodeling are linked to disease activity and stage, and to prognosis across different organs. These signatures accompany and further drive disease progression, and often become detectable before clinical disease manifestation (illness). Recent advances allow to quantify and define the nature of ConT remodeling via blood-based assays that measure the levels of well-defined collagen fragments, reflecting different facets of ConT formation and degradation, and associated immunological processes. These novel serum assays are becoming important tools of precision medicine, to detect various chronic and autoimmune diseases before their clinical manifestation, and to non-invasively monitor the efficacy of a broad range of pharmacological interventions.

Non-Alcoholic Fatty Liver Disease Treatment in Patients with Type 2 Diabetes Mellitus; New Kids on the Block

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), affecting over 25% of the general population worldwide, is characterized by a spectrum of clinical and histological manifestations ranging from simple steatosis (>5% hepatic fat accumulation without inflammation) to non-alcoholic steatohepatitis (NASH) which is characterized by inflammation, and finally fibrosis, often leading to liver cirrhosis, and hepatocellular carcinoma. Up to 70% of patients with type 2 diabetes mellitus (T2DM) have NAFLD, and diabetics have much higher rates of NASH compared with the general non-diabetic population.

OBJECTIVE

The aim of this study is to report recent approaches to NAFLD/NASH treatment in T2DM patients. To-date, there are no approved treatments for NAFLD (apart from lifestyle measures).

RESULTS

Current guidelines (2016) from 3 major scientific organizations suggest that pioglitazone and vitamin E may be useful in a subset of patients for adult NAFLD/NASH patients with T2DM. Newer selective PPAR-γ modulators (SPPARMs, CHRS 131) have shown to provide even better results with fewer side effects in both animal and human studies in T2DM. Newer antidiabetic drugs might also be useful, but detailed studies with histological outcomes are largely lacking. Nevertheless, prior animal and human studies on incretin mimetics, glucagon-like peptide-1 receptor agonists (GLP-1 RA) approved for T2DM treatment, have provided indirect evidence that they may also ameliorate NAFLD/NASH, whereas dipeptidyl dipeptidase-4 inhibitors (DDP-4i) were not better than placebo in reducing liver fat in T2DM patients with NAFLD. Sodium-glucoseco-transporter-2 inhibitors (SGLT2i) have been reported to improve NAFLD/NASH. Statins, being necessary for most patients with T2DM, may also ameliorate NAFLD/NASH, and could potentially reinforce the beneficial effects of the newer antidiabetic drugs, if used in combination, but this remains to be identified.

CONCLUSION

Newer antidiabetic drugs (SPPARMs, GLP-1 RA and SGLT2i) alone or in combination and acting alone or with potent statin therapy which is recommended in T2DM, might contribute substantially to NAFLD/NASH amelioration, possibly reducing not only liver-specific but also cardiovascular morbidity. These observations warrant long term placebo-controlled randomized trials with appropriate power and outcomes, focusing on the general population and more specifically on T2DM with NAFLD/NASH. Certain statins may be useful for treating NAFLD/NASH, while they substantially reduce cardiovascular disease risk.

Association of worsening of nonalcoholic fatty liver disease with cardiometabolic function and intestinal bacterial overgrowth: A cross-sectional study

Background & aims

Non-alcoholic fatty liver disease (NAFLD) has been associated with small bowel bacterial overgrowth (SIBO) and cardiometabolic dysfunction. This cross-sectional study aimed to evaluate the cardio-metabolic parameters and SIBO in patients with different degrees of hepatic fibrosis estimated by NAFLD fibrosis score (NFS).

Methods

Subjects (n = 78) were allocated to three groups: Healthy control (n = 30), NAFLD with low risk of advanced fibrosis (NAFLD-LRAF, n = 17) and NAFLD with a high risk of advanced fibrosis (NAFLD-HRAF, n = 31). Anthropometrics, blood pressure, electrocardiogram and heart rate variability (HRV) were evaluated. Only the NAFLD-LRAF and NAFLD-HRAF groups were submitted to blood biochemical analysis and glucose hydrogen breath tests.

Results

The NAFLD-HRAF group had higher age and body mass index when compared to the control and NAFLD-LRAF groups. The prevalence of SIBO in the NAFLD group was 8.33%. The low frequency/high-frequency ratio (LF/HF ratio) was augmented in NAFLD-LRAF (p < 0.05) when compared with control group. NAFLD-HRAF group had a wide QRS complex (p < 0.05) and reduced LF/HF ratio (p < 0.05) compared to the control and NAFLD-LRAF groups. Serum levels of albumin and platelets were more reduced in the NAFLD-HRAF subjects (p < 0.05) than in the NAFLD-LRAF.

Conclusions

NAFLD impairs cardiac autonomic function. Greater impairment was found in subjects with a worse degree of hepatic fibrosis estimated by NFS. Hypoalbuminemia and thrombocytopenia were higher in subjects with a worse degree of hepatic fibrosis, whereas prevalence of SIBO positive was similar between the groups.

Systemic Nanoparticle-Mediated Delivery of Pantetheinase Vanin-1 Regulates Lipolysis and Adiposity in Abdominal White Adipose Tissue

Lipolysis in white adipose tissue (WAT) occurs in response to nutritional signals and helps to regulate lipid turnover/adiposity in animals. However, the causal relationships and the mechanisms controlling WAT morphology are not clear. In this report, Vanin-1, a pantetheinase, is shown to be a novel determinant for lipolysis and adiposity. The expression of Vanin-1 in the abdominal WAT is positively correlated with lipolysis both in mice and in humans. Mice with global Vanin-1 deficiency exhibit adipocyte hypertrophy and impaired lipolysis. Use of a nanosystem comprising P3-peptide, chitosan oligosaccharide lactate, and polyethylene glycol that controls Vanin-1 expression in the abdominal WAT shows that WAT-specific Vanin-1 knockdown blocks fasting-induced lipolysis and prevents WAT loss. However, WAT-specific Vanin-1 mRNA restoration rescues impaired lipolysis and improves glucose/insulin intolerance in diabetic db/db mice. Mechanistically, Vanin-1 induces PPARγ activity and subsequently facilitates its activation on the proximal promoters of lipolytic genes. Thus, an essential role of Vanin-1 in the regulation of lipolysis and adiposity is revealed, and a functional RNA delivering strategy for specific intervention of Vanin-1 expression in WAT is shown. These findings provide a promising approach to treat metabolic diseases caused by dysregulation of Vanin-1 and lipolysis.

A systematic review and meta-analysis estimating the population prevalence of comorbidities in children and adolescents aged 5 to 18 years

Evidence for the health impact of obesity has largely focussed on adults. We estimated the population prevalence and prevalence ratio of obesity-associated comorbidities in children and adolescents aged 5 to 18 years. Five databases were searched from inception to 14 January 2018. Population-based observational studies reporting comorbidity prevalence by weight category (healthy weight/overweight/obese) in children and adolescents aged 5 to 18 years from any country were eligible. Comorbidity prevalence, stratified by weight category, was extracted and prevalence ratios (relative to healthy weight) estimated using random effects meta-analyses. Of 9183 abstracts, 52 eligible studies (1 553 683 participants) reported prevalence of eight comorbidities or risk markers including diabetes and nonalcoholic fatty liver disease (NAFLD). Evidence for psychological comorbidities was lacking. Meta-analyses suggested prevalence ratio for prediabetes (fasting glucose ≥ 100 mg/dL) for those with obesity relative to those of a healthy weight was 1.4 (95% confidence interval [CI], 1.2-1.6) and for NAFLD 26.1 (9.4-72.3). In the general population, children and adolescents with overweight/obesity have a higher prevalence of comorbidities relative to those of a healthy weight. This review provides clinicians with information when assessing children and researchers a foundation upon which to build a comprehensive dataset to understand the health consequences of childhood obesity.

Environmental microcystin targets the microbiome and increases the risk of intestinal inflammatory pathology via NOX2 in underlying murine model of Nonalcoholic Fatty Liver Disease

With increased climate change pressures likely to influence harmful algal blooms, exposure to microcystin, a known hepatotoxin and a byproduct of cyanobacterial blooms can be a risk factor for NAFLD associated comorbidities. Using both in vivo and in vitro experiments we show that microcystin exposure in NAFLD mice cause rapid alteration of gut microbiome, rise in bacterial genus known for mediating gut inflammation and lactate production. Changes in the microbiome were strongly associated with inflammatory pathology in the intestine, gut leaching, tight junction protein alterations and increased oxidative tyrosyl radicals. Increased lactate producing bacteria from the altered microbiome was associated with increased NOX-2, an NADPH oxidase isoform. Activationof NOX2 caused inflammasome activation as shown by NLRP3/ASCII and NLRP3/Casp-1 colocalizations in these cells while use of mice lacking a crucial NOX2 component attenuated inflammatory pathology and redox changes. Mechanistically, NOX2 mediated peroxynitrite species were primary to inflammasome activation and release of inflammatory mediators. Thus, in conclusion, microcystin exposure in NAFLD could significantly alter intestinal pathology especially by the effects on microbiome and resultant redox status thus advancing our understanding of the co-existence of NAFLD-linked inflammatory bowel disease phenotypes in the clinic.

Rational arrangement of measuring shear wave speed in the liver

BACKGROUND

Shear wave speed has been widely applied to quantify a degree of liver fibrosis. However, there is no standardized procedure, which makes it difficult to utilize the speed universally.

AIM

To provide procedural standardization of shear wave speed measurement.

METHODS

Point shear wave elastography (pSWE) was measured in 781 patients, and two-dimensional shear wave elastography (2dSWE) was measured on the same day in 18 cases. Regions-of-interest were placed at 12 sites, and the median and robust coefficient-of-variation (CVR) were calculated. A residual sum-of-square (Σdi 2) was computed for bootstrap values of 1000 iterations in 18 cases with each assumption of 1 to 12 measurements. The proportion of the Σdi 2 (%Σdi 2) was calculated as the ratio of Σdi 2 to pSWE after converting it based on the correlation between pSWE and 2dSWE.

RESULTS

The CVR showed a significantly broader distribution in the left lobe (P < 0.0001), and the smallest CVR in the right anterior segment that covered 95% cases was 40.4%. pSWE was significantly higher in the left lobe than in the right lobe (1.63 ± 0.78 m/s vs 1.61 ± 0.78 m/s, P = 0.0004), and the difference between the lobes became further discrete when the subjects were limited to the cases with a CVR less than 40.4% in any segment (1.76 ± 0.80 m/s vs 1.70 ± 0.82 m/s, P < 0.0001). The highest values of the CVR in every 0.1 m/s interval were plotted in convex upward along pSWE and peaked at 1.93 m/s. pSWE and 2dSWE were significantly correlated (P < 0.0001, r = 0.95). In 216000 resamples from 18 cases, the %Σdi 2 of 12 sites was 8.0% and gradually increased as the acquisition sites decreased to reach a significant difference with a %Σdi 2 of 7 sites (P = 0.027).

CONCLUSION

These data suggest that shear wave speed should be measured at 8 or more sites of spreading in both lobes.

Non-alcoholic fatty liver disease and pregnancy complications among Sri Lankan women: A cross sectional analytical study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the commonest cause of liver disease worldwide and is the hepatic manifestation of metabolic syndrome. Effects of NAFLD on pregnancy is still unclear with few studies showing an association to gestational diabetes and pre-eclampsia. We aimed to describe the association between the NAFLD and pregnancy complications. This is the first study, to our knowledge, in a South Asian population.

METHOD

A cross sectional analytical study was done in Teaching Hospital, Ragama, Sri Lanka. Women carrying a singleton pregnancy, admitted for delivery were assessed for NAFLD with liver ultrasound scan. Data were extracted from interviewer administered questionnaire and antenatal and inpatient records. Pregnancy complications and labour outcomes were compared between the women with NAFLD and women without NAFLD (non-NAFLD).

RESULTS

Out of the 573 women who participated, 18.2% (n = 104) were found to have NAFLD. Out of them, 58 (55.8%), 32(30.8%), and 14(13.5%) had fatty liver grade 1,2 and 3 respectively. Women with NAFLD were 2 times more likely to develop gestational hypertension and pre-eclampsia compared to the women in the non-NAFLD group, after adjusting for BMI, age and Hyperglycaemia in pregnancy [Adjusted OR 2.09, (95% CI 1.07-4.10)]. There was no association between the grade of steatosis and a composite outcome of gestational hypertension and pre-eclampsia, within the NAFLD group. Composite outcome of gestational diabetes mellitus and diabetes in pregnancy diagnosed during pregnancy was a significant complication in the NAFLD group compared to non-NAFLD group in the bivariate analysis (27.2% vs 17.7%; p<0.05), but the significance disappeared after adjusting for confounders. The current study did not demonstrate a significant association between NAFLD with preterm labour, caesarean section rate, low birth weight, and Apgar score of the baby.

CONCLUSION

Women with NAFLD had a 2-fold higher risk of developing gestational hypertension and pre-eclampsia during pregnancy compared to women without NAFLD, after controlling for other confounding variables.

Evaluation of liver steatosis, measured by controlled attenuation parameter, in patients with hepatitis C-induced advanced liver fibrosis and hepatocellular carcinoma

INTRODUCTION

Steatosis is a documented feature of chronic hepatitis C (CHC). There is an association between steatosis decrease and fibrosis progression. The association between steatosis and advanced fibrosis versus hepatocellular carcinoma (HCC) development has not been precisely evaluated. The controlled attenuation parameter (CAP) was applied as an immediate and efficient process to detect and quantify hepatic steatosis with adequate accuracy.

AIMS

The aim of this study was to assess the difference in liver steatosis between patients with hepatitis C virus-related advanced hepatic fibrosis versus HCC.

PATIENTS AND METHODS

This cross-sectional study included 130 patients with HCC, attending the multidisciplinary HCC clinic, Cairo University, and 54 patients with CHC between October 2015 and June 2016. Clinical and laboratory characteristics were recorded. Liver stiffness and CAP were obtained by using the FibroScan 502, touch.

RESULTS

All included patients had genotype 4. The mean CAP value was significantly lower in HCC (209.5±57.1 dB/m) versus CHC (259.9±54.9 dB/m). Receiver operating characteristic curve revealed an area under the curve of 0.75 for the differentiation between groups. At a cutoff value of 237 dB/m, sensitivity was 72.3%, specificity was 70.7%, positive likelihood ratio was 2.5, and negative likelihood ratio was 0.4 in the differentiation between CHC versus HCC. Logistic regression analysis revealed an odds ratio of 6.4 for the diagnosis of HCC with CAP of less than 237 dB/m. Multivariate analysis, controlling for age, sex, BMI, triglycerides, and cholesterol levels, revealed a significantly increased odds for HCC diagnosis (odds ratio: 4.3, P=0.006).

CONCLUSION

The progression of CHC is associated with a decrease in steatosis, particularly toward advanced fibrosis and HCC. Steatosis reduction less than 237 dB/m is likely to be associated with HCC.

Effect of treatment with direct acting antivirals on body mass index and hepatic steatosis in chronic hepatitis C

Direct Acting Agents (DAAs) have high cure rate but still lack the knowledge of their effect on hepatic steatosis in chronic hepatitis C (CHC). Controlled Attenuation Parameter (CAP), evaluated with transient elastography, could help in assessment of steatosis grades. We aim to evaluate the effect of DAAs on BMI and steatosis in CHC using CAP. This cohort study included 155 CHC Egyptian patients divided into three groups according to the DAAs regimens. All patients were subjected to pre-treatment and 3-months post-treatment evaluation including BMI, laboratory workup and liver stiffness measurement with simultaneous CAP determination using the (FibroScan®) M probe. Patients mean age was 45.78 ± 11.6 years, 60.6% were females, mean BMI 26.63 ± 2.75 and 18.1% were cirrhotic. Baseline assessment revealed no steatosis in 43.9%, 32.9% had mild-moderate steatosis and 23.2% had severe steatosis. The overall sustained virological response 12 was 93.6%. Follow-up revealed stationary steatosis in 56.7% of patients and regression in 21.3%. Mean pre-treatment CAP were significantly lower in responders 244.9 ± 62.4 dB/m versus non-responders; 300 ±28.4 dB/m (P = 0.04). ROC curve delineated 273 dB/m as best cutoff for detection of responders with an AUC of 0.801, sensitivity 68.2%, and specificity 100%. BMI significantly increased after treatment (P = 0.004) particularly in patients with worsened steatosis (P = 0.001). Steatosis significantly correlated with BMI (r = 0.3, P value = < 0.001). DAAs causes a significant change in steatosis grade in a subset of treated patients. Pretreatment CAP was significantly lower in responders. BMI significantly increases following treatment particularly in patients with worsened steatosis.

Non-alcoholic fatty liver disease: controlling an emerging epidemic, challenges, and future directions

Non-alcoholic fatty liver disease (NAFLD) affects over 30% of the United States population and is projected to become a leading cause of chronic liver disease by 2020. As a result, the economic and societal burden of NAFLD is far-reaching. The cost of managing NAFLD complications has an estimated 10 year economic burden of $908 billion. This review provides an overview of current knowledge on NAFLD, with emphasis on identifying gaps in its diagnosis and management, and proposes future directions to address these limitations. Despite the increasing prevalence of NAFLD, there is limited knowledge and practice regarding its natural history, staging, diagnosis, and management. Though a challenging task, opportunities for bridging these gaps should focus on the development of noninvasive biomarkers, the elucidation of biological pathways, the creation of up-to-date screening guidelines, and the organization of clinical trials of longer duration to determine clinical endpoints and assess the safety of new treatment options.

Regional differences in sorafenib-treated patients with hepatocellular carcinoma: GIDEON observational study

BACKGROUND & AIMS

Treatment approaches for hepatocellular carcinoma (HCC) vary across countries, but these differences and their potential impact on outcomes have not been comprehensively assessed. Data from the multinational GIDEON (Global Investigation of therapeutic DEcisions in HCC and Of its treatment with sorafeNib) registry evaluated differences in patient characteristics, practice patterns and outcomes in HCC across geographical regions in patients who received sorafenib.

METHODS

GIDEON is a non-randomised, observational registry study conducted in 39 countries across five global regions. HCC patients in whom a decision to treat with sorafenib was made in clinical practice and according to local practices were included.

RESULTS

3202 patients were evaluable for safety analysis: Asia-Pacific (n = 928), Japan (n = 508), Europe (n = 1113), USA (n = 563) and Latin America (n = 90). Patients in Japan had earlier-stage disease at initial diagnosis compared with patients in other regions (Barcelona Clinic Liver Cancer stage A; 43.7% vs 9.1-24.3%). Use of locoregional therapies before sorafenib, including transarterial chemoembolisation, was more common in Japan (84.4%) and Asia-Pacific (67.2%) compared with the USA (49.4%) and Europe (43.5%). Treatment patterns with respect to sorafenib also differed, with a shorter duration of treatment reported in the USA and Asia-Pacific. Time from initial diagnosis to death was longer in Japan compared with other regions (median, 79.6 months vs 14.8-25.0 months).

CONCLUSIONS

Data from GIDEON highlight regional variations in the management of HCC and patient outcomes. Greater standardisation of management may help optimise outcomes for HCC patients.

Free Fatty Acids Increase Intracellular Lipid Accumulation and Oxidative Stress by Modulating PPARα and SREBP-1c in L-02 Cells

Excessive fat accumulation and increased oxidative stress contribute to the pathogenesis of nonalcoholic fatty liver disease (NAFLD). However, the mechanisms underlying the development of steatosis are not entirely understood. The present study was undertaken to establish an experimental model of hepatocellular steatosis with a fat overaccumulation profile in which the effects of oxidative stress could be studied in L-02 cells. We investigated the effects of free fatty acids (FFA) (palmitate:oleate, 1:2) on lipid accumulation and oxidative stress and their possible mechanisms in L-02 cells. High concentrations of fatty acids significantly induced excessive lipid accumulation and oxidative stress in L-02 cells, which could only be reversed with 50 μΜ WY14643 (the PPARα agonist). Immunoblotting and qPCR analyses revealed that FFA downregulated the expression of proliferator-activated receptor alpha (PPARα), which contributed to the increased activation of sterol regulatory element binding protein-1c (SREBP-1c). These results suggest that FFA induce lipid accumulation and oxidative stress in L-02 cells by upregulating SREBP-1c expression through the suppression of PPARα.

Steatosis and hepatitis C

Hepatitis C virus (HCV) infection is a common liver disease worldwide with a high rate of chronicity (75-80%) in infected individuals. The chronic form of HCV leads to steatosis, cirrhosis and hepatocellualr carcinoma. Steatosis is prevalent in HCV patients (55%) due to a combination of viral factors (effect of viral proteins on some of the intracellular pathways) and host factors (overweight, insulin resistance, diabetes mellitus, and alcohol consumption). The response rates to treatment of chronic HCV with pegylated interferon (PEG-IFN) and (in the case of genotype-1 HCV, the most common infecting genotype in the USA) ribavirin (RBV) is low, with a sustained viral response rate ≤ 40%. Adding direct-acting antiviral agents-recently approved by the FDA-to the standard protocol has increased the response rate; however HCV-related end-stage liver disease is still the primary indication for liver transplantation in the USA. The focus of this article is on the interrelation between HCV, steatosis and metabolic syndrome.

Elevated Linoleic Acid (A Pro-Inflammatory PUFA) and Liver Injury in a Treatment Naive HIV-HCV Co-Infected Alcohol Dependent Patient

HIV and HCV co-infection is a unique disease condition, and medical management of such condition is difficult due to severity and systemic complications. Added with heavy alcohol drinking, risk of liver injury increases due to several pro-inflammatory responses that subsequently get involved with alcohol metabolism. Elevated levels of fatty acids have been reported both in viral infections as well as alcoholic liver disease though such investigations have not addressed the adverse events with dual viral infection of HIV and HCV along with heavy drinking. This case report is of a patient with excessive alcohol drinking and first time diagnosis of HIV and HCV dual infection, elaborating concurrent alteration in Linoleic Acid (LA) levels and pro-inflammatory shift in ω-6/ω-3 ratio along with the elevations in liver injury markers. Elevated LA has been recently studied extensively for its role in alcoholic liver disease; and in the present case, we also found it to be clinically relevant to liver injury.

Call for standardized definitions of osteoarthritis and risk stratification for clinical trials and clinical use

Osteoarthritis (OA) is a heterogeneous disorder. The goals of this review are (1) To stimulate use of standardized nomenclature for OA that could serve as building blocks for describing OA and defining OA phenotypes, in short to provide unifying disease concepts for a heterogeneous disorder; and (2) To stimulate establishment of ROAD (Risk of OA Development) and ROAP (Risk of OA Progression) tools analogous to the FRAX™ instrument for predicting risk of fracture in osteoporosis; and (3) To stimulate formulation of tools for identifying disease in its early preradiographic and/or molecular stages - REDI (Reliable Early Disease Identification). Consensus around more sensitive and specific diagnostic criteria for OA could spur development of disease modifying therapies for this entity that has proved so recalcitrant to date. We fully acknowledge that as we move forward, we expect to develop more sophisticated definitions, terminology and tools.

Feeding soy protein isolate and n-3 PUFA affects polycystic liver disease progression in a PCK rat model of autosomal polycystic kidney disease

OBJECTIVE

In polycystic liver disease (PCLD), multiple cysts cause liver enlargement, structural damage, and loss of function. Soy protein and dietary ω-3 polyunsaturated fatty acids (n-3 PUFAs) have been found to decrease cyst proliferation and inflammation in polycystic kidney disease. Therefore, the aim of the study was to investigate whether soy protein and n-3 PUFA supplementation attenuates PCLD.

METHODS

Young (age 28 days) female PCK rats were fed (n = 12 per group) either casein + corn oil (casein + CO), casein + soybean oil (casein + SO), soy protein isolate + soybean oil (SPI + SO), or SPI + 1:1 soybean/salmon oil blend (SPI + SB) diet for 12 weeks. Liver histology, gene expression by real-time quantitative polymerase chain reaction, and serum markers of liver injury were determined.

RESULTS

Diet had no effect on PCLD progression as indicated by no significant differences in liver weight and hepatic proliferation gene expression between diet groups. PCK rats fed SPI + SB diet, however, had the greatest (P < 0.05) histological evidence of hepatic cyst obstruction, portal inflammation, steatosis, and upregulation (P = 0.03) of fibrosis-related genes. Rats fed SPI + SB diet also had the lowest (P < 0.001) serum cholesterol and higher (P < 0.05) serum alkaline phosphatase and bilirubin concentrations.

CONCLUSIONS

Feeding young female PCK rats SPI and n-3 PUFA failed to attenuate PCLD progression. Furthermore, feeding SPI + SB diet resulted in complications of hepatic steatosis attributable to cysts obstruction of bile duct and hepatic vein. Based on the results, it was concluded that diet intervention alone was not effective at attenuating PCLD associated with autosomal recessive polycystic kidney disease.

Steatosis-induced proteins adducts with lipid peroxidation products and nuclear electrophilic stress in hepatocytes

Accumulating evidence suggests that fatty livers are particularly more susceptible to several pathological conditions, including hepatic inflammation, cirrhosis and liver cancer. However the exact mechanism of such susceptibility is still largely obscure. The current study aimed to elucidate the effect of hepatocytes lipid accumulation on the nuclear electrophilic stress. Accumulation of intracellular lipids was significantly increased in HepG2 cells incubated with fatty acid (FA) complex (1 mM, 2:1 oleic and palmitic acids). In FA-treated cells, lipid droplets were localized around the nucleus and seemed to induce mechanical force, leading to the disruption of the nucleus morphology. Level of reactive oxygen species (ROS) was significantly increased in FA-loaded cells and was further augmented by treatment with moderate stressor (CoCl₂). Increased ROS resulted in formation of reactive carbonyls (aldehydes and ketones, derived from lipid peroxidation) with a strong perinuclear accumulation. Mass-spectroscopy analysis indicated that lipid accumulation per-se can results in modification of nuclear protein by reactive lipid peroxidation products (oxoLPP). 235 Modified proteins involved in transcription regulation, splicing, protein synthesis and degradation, DNA repair and lipid metabolism were identified uniquely in FA-treated cells. These findings suggest that steatosis can affect nuclear redox state, and induce modifications of nuclear proteins by reactive oxoLPP accumulated in the perinuclear space upon FA-treatment.

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Effects of fatty acids on modification of nuclear proteins in hepatocytes was studied.

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Lipid accumulation was associated with abnormal nuclear morphology.

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Lipid accumulation promoted mitochondrial activity and enhanced ROS generation.

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Nuclear proteins were modified by lipid peroxidation products.

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Data suggest nuclear stress as a mechanism for fatty liver disease progression.

Detection of hepatic steatosis using the controlled attenuation parameter: a comparative study with liver biopsy

OBJECTIVE

Measurements of controlled attenuation parameter (CAP) with transient elastography (FibroScan®; EcoSens SA, Paris, France) may provide an accurate noninvasive assessment of hepatic steatosis. Herein, we prospectively determined the accuracy of liver fat quantification with CAP values in patients with chronic liver diseases and compare the results with those of histological assessment of steatosis as reference standard.

MATERIALS AND METHODS

We enrolled 50 Turkish patients with various forms of chronic liver diseases. All patients underwent both CAP assessment and ultrasonography-guided liver biopsy.

RESULTS

On liver biopsy, 16 (32%) patients had S0, 12 (24%) had S1, 9 (18%) had S2, and 13 (26%) had S3. The CAP values increased significantly (p<0.001) for each steatosis stage on liver biopsy: S0, 222 dB/m; S1, 250 dB/m; S2, 270 dB/m; and S3, 318 dB/m. A cutoff value of 257 dB/m could distinguish significant steatosis (S2-S3) from S0 (Sn 89%, Sp 83%, positive likelihood ratio 5.33, negative likelihood ratio 0.13, AUROC=0.93). Multivariable analysis indicated that neither liver fibrosis (p=0.58) nor disease etiology (p=0.96) had a significant impact on the association between CAP and the stage of steatosis.

CONCLUSION

The determination of CAP using transient elastography can represent an important step forward toward the goal of an "imaging liver biopsy".

The impact of host metabolic factors on treatment outcome in chronic hepatitis C

Background. Recent data suggest that chronic hepatitis C has to be considered a metabolic disease further to a viral infection. The aim of this study was to elaborate on the complex interactions between hepatitis C virus, host metabolic factors, and treatment response. Methods. Demographic, virological, and histological data from 356 consecutive patients were analyzed retrospectively. Hepatic steatosis, obesity, and insulin resistance were examined in relation to their impact on treatment outcome. Comparison between genotype 1 and 3 patients was performed to identify differences in the determinants of hepatic steatosis. Results. Histological evidence of hepatic steatosis was found in 113 patients, distributed in 20.3%, 9.0%, and 2.5% for grades I, II, and III, respectively. Hepatic steatosis was associated with past alcohol abuse (P = 0.003) and histological evidence of advanced fibrosis (P < 0.001). Older age (OR 2.51, P = 0.002), genotype (OR 3.28, P < 0.001), cirrhosis (OR 4.23, P = 0.005), and hepatic steatosis (OR 2.48, P = 0.001) were independent predictors for nonresponse. Correlations of hepatic steatosis with alcohol, insulin resistance, and fibrosis stage were found similar for both genotypes 1 and 3. Conclusions. Host metabolic factors may predict treatment outcome, and this impact remains significant even in genotype 3, where steatosis has been believed to be exclusively virus related.

Multi-excitation fluorescence spectroscopy for analysis of non-alcoholic fatty liver disease

BACKGROUND AND OBJECTIVES

The increasing incidence of non-alcoholic fatty liver diseases (NAFLD) and the consequent progression to cirrhosis is expected to become a major cause of liver transplantation. This will exacerbate the organ donor shortage and mean that 'marginal' fatty liver grafts are more frequently used. Autofluorescence spectroscopy is a fast, objective, and non-destructive method to detect change in the endogenous fluorophores distribution and could prove to be a valuable tool for NAFLD diagnosis and transplant graft assessment.

MATERIALS AND METHODS

A system was constructed consisting of a fibre probe with two laser diodes that provided excitation light at 375 and 405 nm, and an imaging spectrograph system. This was used to distinguish fluorescence spectra acquired from the harvested livers from mice with NAFLD of differing severity (healthy, mild steatotic and steatohepatitic). The fluorescence data were entered into a sparse multiclass probabilistic algorithm for disease classification. Histopathology, thiobarbituric acid reactive substances (TBARS) and alanine transaminase (ALT) assays were conducted in addition to the fluorescence measurements

RESULTS

TBARS and ALT assays enabled differentiation of the steatohepatitic group from the mild steatosis and control groups (P ≤ 0.028) but failed to separate the mild steatotic group from the control group. The three groups were all clearly differentiated from each other using fluorescence spectroscopy, and classification accuracy was found to be 95%.

CONCLUSION

Fluorescence spectroscopy appears to be a promising approach for the analysis of diseased liver tissue.

Clinical characteristics associated with hepatic steatosis on ultrasonography in patients with elevated alanine aminotransferase

CONTEXT AND OBJECTIVE

The main causes of hepatic steatosis (HS) are alcoholic liver disease and nonalcoholic fatty liver disease (NAFLD). Although liver biopsy is the gold standard for NAFLD diagnosis, the finding of abnormal aminotransferases in abstinent individuals, without known liver disease, suggests the diagnosis of NAFLD in 80-90% of the cases. Identification of clinical factors associated with HS on abdominal ultrasound may enable diagnoses of fatty liver non-invasively and cost-effectively. The aim here was to identify clinical variables associated with HS in individuals with elevated alanine aminotransferase (ALT) levels.

DESIGN AND SETTING

Cross-sectional study in a single tertiary care center.

METHODS

Individuals with elevated ALT, serologically negative for hepatitis B and C, were evaluated by reviewing medical files. Patients who did not undergo abdominal ultrasonography were excluded.

RESULTS

Among 94 individuals included, 40% presented HS on ultrasonography. Compared with individuals without HS, those with fatty liver were older (P = 0.043), with higher body mass index (BMI) (P = 0.003), diabetes prevalence (P = 0.024), fasting glucose levels (P = 0.001) and triglycerides (P = 0.003). Multivariate analysis showed that BMI (odds ratio, OR = 1.186; 95% confidence interval, CI: 1.049-1.341; P = 0.006) and diabetes mellitus (OR = 12.721; 95% CI: 1.380-117.247; P = 0.025) were independently associated with HS.

CONCLUSIONS

Simple clinical findings such as history of diabetes and high BMI may predict the presence of HS on ultrasonography in individuals with elevated ALT and negative serological tests for hepatitis.

Fatty liver and global cardiometabolic risk

A nem alkoholos zsírmáj betegség (NAFLD = nonalcoholic fatty liver disease) az „iparilag fejlett” országok felnőtt lakosságának 30%-ában észlelhető. Előrehaladott, súlyosabb formája a nem alkoholos steatohepatitis (NASH = nonalcoholic steatohepatitis), amelyből az esetek 20%-ában cirrhosis alakul ki, a kialakult cirrhosis mintegy 30–40%-a májeredetű halálhoz, elsősorban hepatocellularis carcinomához vezethet. Az NAFLD-t sokan a metabolikus szindróma májbeli manifesztációjának tartják, e két jelenség kapcsolatát tekintjük át, különös tekintettel a hasi elhízás, az inzulinrezisztencia, az oxidatív stressz és a csökkent antioxidáns védelem kóroki szerepére. A májsejtek trigliceridtartalmának növekedése együtt jár az egész szervezet, illetve a máj inzulinrezisztenciájával. Klasszikus tyúk–tojás probléma: a lipidlerakódás oka az inzulinrezisztencia, vagy az inzulinrezisztencia az ectopiás lipidfelhalmozódás következménye? A patogenetikai történések egy lehetséges sorrendje: megnövekedett zsírsavfluxus, a májbeli zsírsavkínálat növekedése → VLDL-túltermelődés, atherogen dyslipidaemia → a zsírsavak fokozott oxidációja és peroxidációja, enormis szabadgyök-terhelés → az antioxidáns védekezőrendszer kimerülése → a gyulladást és az immunválaszt kiváltó mediátorok „cunamiszerű” kiáramlása → a fibrosis progresszióját elősegítő transzkripciós és transzlációs változások → carcinogenesis. Az NAFLD és a metabolikus szindróma egyaránt része a globális kardiometabolikus kockázatnak, így lényeges a korai felismerés, és – amennyiben lehetséges a kezelés – ez ma a metabolikus szindróma részelemeinek kezelési ajánlásaiban testesül meg. Orv. Hetil., 2010, 47, 1946–1950.

Endosulfan in vitro toxicity in Atlantic salmon hepatocytes obtained from fish fed either fish oil or vegetable oil

The composition of the feed may alter the cellular composition of an organism and thus has the potential to influence a xenobiotic response. The main aim of this study was to see if the fatty acid composition of primary hepatocytes isolated from Atlantic salmon (Salmo salar L.) obtained from fish fed either a fish oil or a vegetable oil based diet, influenced the response to endosulfan exposure in vitro. The primary cultures were exposed to six different concentrations of endosulfan (0.001, 0.01, 0.1, 1, 10 and 100 microM) for 48 h. Cell morphology as well as a molecular toolbox of 16 genes encoding stress responsive and biotransformation proteins was examined. Endosulfan exposure caused moderate cytotoxicity and steatosis in a dose-dependent manner in the hepatocytes. In general, endosulfan hepatoxicity seems to be unaffected by the fatty acid composition of the hepatocytes. Exceptions were general stress (HSP70) and markers for estrogen exposure (ZP and VTG), which appeared to be slightly less responsive in hepatocytes isolated from the vegetable oil fed fish.

Geriatric veterinary care for fish patients

There is little evidence-based research and scientific literature available for providing geriatric care for fish patients. Fish can have tremendous longevity. Although the average life span for most fish species can be only a few days to weeks for the beginning hobbyist, it is becoming more common for clients to have animals for several decades with the advent and continued development of improved life-support systems, husbandry, water quality additives, and fish nutrition. This article discusses fish longevity for several popular species, addresses environmental quality issues for geriatric patients, and provides information on the most common challenges, from a veterinary perspective, to maintain fish over the years.

Insulin resistance and not steatosis is associated with modifications in oxidative stress markers in chronic hepatitis C, non-3 genotype

BACKGROUND

Modifications of oxidative stress are reported in hepatitis C. The relationship between insulin resistance (IR), steatosis and oxidative stress is not established.

MATERIALS AND METHODS

One hundred and eighty-seven HCV-RNA patients were assessed by determination of biochemical, metabolic and viral features, HOMA-IR and morphological alterations. In the 52-non-3 genotypes sub-group and 35 healthy individuals, thiobarbituric acid (TBARS), total glutathione (total-GSH), vitamins C and E, lycopene, beta-carotene, glutathione peroxidase (GPx), catalase and superoxide dismutase were determined.

RESULTS

In non-3 genotype patients, steatosis was associated with higher values of BMI, HOMA-IR and triglycerides. In the 52-HCV sub-group, values of TBARS, GPx and total-GSH differ from the control group. Despite these, differences could not be observed according to the presence of steatosis, patients with IR presented significant differences regarding total-GSH (p=0.019), beta-carotene (p=0.006), lycopene (p=0.005) and GPx (p=0.009).

CONCLUSION

In non-3 genotype HCV carries, IR, and not steatosis, is associated with modifications in serum levels of oxidative stress.

Independent predictors of fibrosis in patients with nonalcoholic fatty liver disease

BACKGROUND & AIMS

Nonalcoholic fatty liver disease (NAFLD) is a common cause of chronic liver disease. We investigated factors associated with advanced fibrosis in NAFLD.

METHODS

The study included 432 patients with histologically proven NAFLD (26.8% with nonalcoholic steatohepatitis [NASH] and 17.4% with moderate-to severe fibrosis). NASH was defined as steatosis, lobular inflammation, and ballooning degeneration with or without Mallory-Denk bodies and/or fibrosis. Fibrosis was classified into 2 groups: those with no or minimal fibrosis and those with moderate-to-severe fibrosis. Groups were compared using Mann-Whitney and chi-square method analyses. A model was constructed using a stepwise bidirectional method; its predictive power was measured using a 10-fold cross-validation technique.

RESULTS

Patients with NASH were more likely to be male (P < .0001); have lower hip-to-waist ratios (P = .03); were less likely to be African American (P = .06); have higher levels of alanine aminotransferase (ALT; P < .0001), aspartate aminotransferase (AST; P < .0001), and serum triglycerides (P = .0154), but lower levels of high-density lipoprotein cholesterol (P < .0001). Patients with moderate-to-severe fibrosis were older (P = .0245); more likely to be male (P = .0189), Caucasian (P = .0382), have diabetes mellitus (P = .0238), and hypertension (P = .0375); and have a lower hip-to-waist ratio (P = .0077) but higher serum AST (P < .0001) and ALT (P < .0001) levels. The multivariate analysis model to predict moderate-to-severe fibrosis included male sex, Caucasian ethnicity, diabetes mellitus, and increased AST and ALT levels (model P value < .0001).

CONCLUSIONS

In patients with NAFLD, diabetes mellitus and aminotransferase levels are independent predictors of moderate-to-severe fibrosis. They can be used to identify NAFLD patients at risk for advanced fibrosis.

Imaging-based quantification of hepatic fat: methods and clinical applications

Fatty liver disease comprises a spectrum of conditions (simple hepatic steatosis, steatohepatitis with inflammatory changes, and end-stage liver disease with fibrosis and cirrhosis). Hepatic steatosis is often associated with diabetes and obesity and may be secondary to alcohol and drug use, toxins, viral infections, and metabolic diseases. Detection and quantification of liver fat have many clinical applications, and early recognition is crucial to institute appropriate management and prevent progression. Histopathologic analysis is the reference standard to detect and quantify fat in the liver, but results are vulnerable to sampling error. Moreover, it can cause morbidity and complications and cannot be repeated often enough to monitor treatment response. Imaging can be repeated regularly and allows assessment of the entire liver, thus avoiding sampling error. Selection of appropriate imaging methods demands understanding of their advantages and limitations and the suitable clinical setting. Ultrasonography is effective for detecting moderate or severe fatty infiltration but is limited by lack of interobserver reliability and intraobserver reproducibility. Computed tomography allows quantitative and qualitative evaluation and is generally highly accurate and reliable; however, the results may be confounded by hepatic parenchymal changes due to cirrhosis or depositional diseases. Magnetic resonance (MR) imaging with appropriate sequences (eg, chemical shift techniques) has similarly high sensitivity, and MR spectroscopy provides unique advantages for some applications. However, both are expensive and too complex to be used to monitor steatosis.

Lipid aldehyde-mediated cross-linking of apolipoprotein B-100 inhibits secretion from HepG2 cells

Hepatic oxidative stress and lipid peroxidation are common features of several prevalent disease states, including alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD), a common component of the metabolic syndrome. These conditions are characterized in part by excessive accumulation of lipids within hepatocytes, which can lead to autocatalytic degradation of cellular lipids giving rise to electrophilic end products of lipid peroxidation. The pathobiology of reactive lipid aldehydes remains poorly understood. We therefore sought to investigate the effects of 4-hydroxynonenal (4-HNE) and 4-oxononenal (4-ONE) on the transport and secretion of very low-density lipoprotein using HepG2 cells as a model hepatocyte system. Physiologically relevant concentrations of 4-HNE and 4-ONE rapidly disrupted cellular microtubules in a concentration-dependent manner. Interestingly, 4-ONE reduced apolipoprotein B-100 (ApoB) secretion while 4-HNE did not significantly impair secretion. Both 4-HNE and 4-ONE formed adducts with ApoB protein, but 4-HNE adducts were detectable as mono-adducts, while 4-ONE adducts were present as protein-protein cross-links. These results demonstrate that reactive aldehydes generated by lipid peroxidation can differ in their biological effects, and that these differences can be mechanistically explained by the structures of the protein adducts formed.

Endocrine manifestations of hepatitis C virus infection

Chronic infection with hepatitis C virus (HCV) can result in both hepatic and extrahepatic disease and endocrine dysfunction represents an important class of HCV-related extrahepatic disease. The most frequently occurring--and clinically important--of these endocrine disorders are thyroid disease and type 2 diabetes mellitus. In this Review, we evaluate the evidence in support of a link between HCV infection and endocrine-system dysfunction, and discuss potential pathophysiological mechanisms. A meta-analysis of the literature has revealed significant associations between chronic HCV infection, thyroid autoimmunity and hypothyroidism. Furthermore, a high prevalence of thyroid cancer has been reported in HCV-positive patients. Several clinicoepidemiological studies have demonstrated that chronic HCV infection could lead to the development of type 2 diabetes mellitus, possibly as a result of HCV-induced metabolic disturbances. Some researchers have postulated that a type 1 T-helper -cell mediated immune response underpins the association of chronic HCV infection with endocrine disease. Indeed, the available data suggest that a common immunological, type 1 T-helper cell pattern of cytokine expression and activation (via interferon-gamma) could provide the pathophysiological basis for this association. Nonetheless, additional studies will be necessary to elucidate fully all the mechanisms involved in HCV-related endocrine dysfunction.

Rosiglitazone aggravates nonalcoholic Fatty pancreatic disease in C57BL/6 mice fed high-fat and high-sucrose diet

OBJECTIVES

Evaluate the effect of fenofibrate, bezafibrate, and rosiglitazone on nonalcoholic fatty pancreatic disease and islet peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and PPAR-beta immunostain in mice fed high-fat high-sucrose (HFHS) diet.

METHODS

Two-month-old male mice were fed standard chow (n = 10) or HFHS chow (n = 40) for 6 weeks. Afterward, HFHS mice were grouped by treatment: untreated HFHS and HFHS treated with rosiglitazone (HFHS-Ro), fenofibrate (HFHS-Fe), or bezafibrate (HFHS-Bz). Medications were administered for 5 weeks. After treatment, the pancreas was removed and analyzed by morphometry, stereology, and immunohistochemistry.

RESULTS

The HFHS-fed mice showed altered fasting glucose (+33%) and insulin (+138%); increased body (+20%) and pancreas (+28%) masses, pancreatic fat (+700%), islet hypertrophy (+38%); and decreased GLUT2 immunostain (-60%). Rosiglitazone reduced fasting glucose and insulin but induced weight gain. Fibrates impeded weight gain, but only bezafibrate prevented islet hypertrophy. The GLUT2 stain was improved in all treatments, and there were no alterations in PPAR-alpha. There were morphological signs of pancreatitis with fenofibrate, although there were no alterations in amylase and lipase. Rosiglitazone exacerbated pancreatic fat infiltration (+75% vs HFHS group), and bezafibrate increased PPAR-beta expression in pancreatic islets.

CONCLUSIONS

Rosiglitazone is shown for the first time to exacerbate pancreatic fat infiltration; therefore, precaution has to be taken when rosiglitazone is prescribed to obese patients.