Nonalcoholic fatty liver disease and hepatocellular carcinoma:Insights in epidemiology, pathogenesis, imaging, prevention and therapy.

Hepatocellular carcinoma (HCC) is estimated to be the third leading cause of cancer-related mortality and is characterized by low survival rates. Nonalcoholic fatty liver disease (NAFLD) is emerging as a leading cause of HCC, whose rates are increasing, owing to the increasing prevalence of NAFLD. The pathogenesis of NAFLD-associated HCC is multifactorial: insulin resistance, obesity, diabetes and the low-grade hepatic inflammation, which characterizes NAFLD, seem to play key roles in the development and progression of HCC. The diagnosis of NAFLD-associated HCC is based on imaging in the presence of liver cirrhosis, preferably computerized tomography or magnetic resonance imaging, but liver biopsy for histological confirmation is usually required in the absence of liver cirrhosis. Some preventive measures have been recommended for NAFLD-associated HCC, including weight loss, cessation of even moderate alcohol drinking and smoking, as well as the use of metformin, statins and aspirin. However, these preventive measures are mainly based on observational studies, thus they need validation in trials of different design before introducing in clinical practice. The treatment of NAFLD should be tailored on an individual basis and should be ideally determined by a multidisciplinary team. In the last two decades, new medications, including tyrosine kinase inhibitors and immune checkpoints inhibitors, have improved the survival of patients with advanced HCC, but trials specifically designed for patients with NAFLD-associated HCC are scarce. The aim of this review was to overview evidence on the epidemiology and pathophysiology of NAFLD-associated HCC, then to comment on imaging tools for its appropriate screening and diagnosis, and finally to critically summarize the currently available options for its prevention and treatment.

The association of testosterone with sarcopenia and frailty in chronic liver disease.

BACKGROUND: Testosterone is an important anabolic hormone responsible for maintaining body composition and muscle mass and circulates mostly albumin-bound, or sex hormone binding globulin (SHBG)-bound or free in the plasma. Of these fractions, the latter is bioactive and exerts the androgenic effects on male population. Liver cirrhosis, the advanced stage of any chronic liver disease characterized by permanent distortions to the hepatic architecture, disrupts the hypothalamic-pituitary-gonadal axis, leading to diminished levels of free testosterone and hypogonadism. METHODS: We retrieved the PubMed database to provide a synopsis of testosterone's physiology and action and summarize the effect of sarcopenia in pre-cirrhotic and cirrhotic patients. Moreover, we scoped to provide insight into the relationship of testosterone levels with sarcopenia, frailty and survival in cirrhotic and non-cirrhotic population as well as to discuss the efficacy of exogenous testosterone supplementation on the anthropometric parameters and survival of those patients. RESULTS: Low testosterone levels have been associated with sarcopenia, reduced body lean mass, decreased bone mineral density and frailty, thus leading to increased morbidity and mortality especially among cirrhotic patients. Furthermore, exogenous testosterone administration significantly ameliorated body composition on patients with chronic hepatic disease, without significant adverse effects. However, the current literature does not suggest any significant effect on survival of those patients. Moreover, the long-term safety of testosterone use remains an open question. CONCLUSION: Low serum testosterone is strongly correlated with sarcopenia, frailty, higher rate of hepatic decompensation and mortality. Nonetheless, exogenous supplementation of testosterone did not ameliorate the liver-related outcomes and complications.

Glucagon-like Peptide 1, Glucose-Dependent Insulinotropic Polypeptide, and Glucagon Receptor Agonists in Metabolic Dysfunction-Associated Steatotic Liver Disease: Novel Medication in New Liver Disease Nomenclature.

Glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretins that regulate postprandial glucose regulation, stimulating insulin secretion from pancreatic ß-cells in response to food ingestion. Modified GLP-1 receptor agonists (GLP-1RAs) are being administered for the treatment of obesity and type 2 diabetes mellitus (T2DM). Strongly related to those disorders, metabolic dysfunction-associated steatotic liver disease (MASLD), especially its aggressive form, defined as metabolic dysfunction-associated steatohepatitis (MASH), is a major healthcare burden associated with high morbidity and extrahepatic complications. GLP-1RAs have been explored in MASH patients with evident improvement in liver dysfunction enzymes, glycemic control, and weight loss. Importantly, the combination of GLP-1RAs with GIP and/or glucagon RAs may be even more effective via synergistic mechanisms in amelioration of metabolic, biochemical, and histological parameters of MASLD but also has a beneficial impact on MASLD-related complications. In this current review, we aim to provide an overview of incretins' physiology, action, and signaling. Furthermore, we provide insight into the key pathophysiological mechanisms through which they impact MASLD aspects, as well as we analyze clinical data from human interventional studies. Finally, we discuss the current challenges and future perspectives pertinent to this growing area of research and clinical medicine.

Circulating cell-free DNA species affect the risk of hepatocellular carcinoma in treated chronic hepatitis B patients.

Hepatocellular carcinoma (HCC) may still develop in chronic hepatitis B (CHB) patients even under effective long-term oral antiviral therapy, but its pathogenesis in the setting of long-standing inhibition of viral replication has not been completely elucidated. We investigated whether species of circulating cell-free DNA (cfDNA) may be involved in the process of hepatocarcinogenesis in treated CHB patients. Serum samples were obtained from HBeAg-negative CHB patients with (HCC cases, n = 37) or without HCC development during the first 5 years of oral antiviral therapy (controls, n = 74). HCC cases and controls were matched 1:2 for age, sex and platelets. Determination of different circulating cfDNA species (before HCC diagnosis in HCC cases) including total cfDNA quantity, levels of Alu repeat DNA and RNase P coding DNA, copies of mitochondrial DNA and levels of 5-methyl-2'-deoxycytidine as an indicator of DNA methylation was performed. HCC cases compared with controls had higher median levels of Alu247 (123 vs 69 genomic equivalent, p = .042) and RNase P coding DNA (68 vs 15 genomic equivalent, p < .001). In contrast, median cfDNA concentration, Alu115 levels, Alu247/Alu115 ratio as an index of DNA integrity and mitochondrial DNA copies did not differ significantly between HCC cases and controls. Receiver operating characteristic curve analysis showed that levels RNase P coding DNA offered good prediction of subsequent HCC development (c-statistic: 0.80, p < .001). In conclusion, serum levels of RNase P coding DNA are increased years before HCC diagnosis and could be potentially helpful in the prediction of the HCC risk in treated HBeAg-negative CHB patients.

The Role of Senescence in the Development of Nonalcoholic Fatty Liver Disease and Progression to Nonalcoholic Steatohepatitis.

In recent years, cellular senescence has generated a lot of interest among researchers because of its involvement in both the normal aging process and common human diseases. During senescence, cells undergo alterations that include telomere shortening, nuclear area enlargement, and genomic and mitochondrial DNA damage, leading to irreversible cell cycle arrest, and secretion of proinflammatory cytokines. Evidence suggests that the complex process of senescence is involved in the development of a plethora of chronic diseases including metabolic and inflammatory disorders and tumorigenesis. Recently, several human and animal studies have emphasized the involvement of senescence in the pathogenesis and development of liver steatosis including the progression to nonalcoholic steatohepatitis (NASH) as characterized by the additional emergence of inflammation, hepatocyte ballooning, and liver fibrosis. The development of nonalcoholic fatty liver disease (NAFLD) and its progression to NASH are commonly accompanied by several pathophysiological events including metabolic dysregulation and inflammatory phenomena occurring within the liver that may contribute to or derive from cellular senescence, implying that the latter may be both a stimulus and a consequence of the disease. Conclusion: In this review, we summarize the current literature on the impact of cellular senescence in NAFLD/NASH and discuss the effectiveness and safety of novel senolytic drugs and therapeutic options available to delay or treat the disease. Finally, we identify the open questions and issues to be addressed in the near future.

The impact of sodium glucose co-transporter 2 inhibitors on non-alcoholic fatty liver disease.

Affecting one fourth of the global population, non-alcoholic fatty liver disease (NAFLD) is the commonest chronic liver disorder. It encompasses the simple liver fat accumulation to more progressive steatosis, inflammation, and fibrosis characterized as non-alcoholic steatohepatitis (NASH) and in some cases cirrhosis and hepatocellular carcinoma. NAFLD regularly coexists with metabolic disorders, such as obesity and mostly type 2 diabetes mellitus (T2DM). A relatively new class of antidiabetic drugs, the sodium glucose co-transporter 2 (SGLT2) inhibitors exert their action by increasing the urinary glucose and calorie excretion leading to ameliorated plasma glucose levels and lower bodyweight. Recently, several animal studies and human clinical trial have emphasized the possible beneficial impact of SGLT2 inhibitors on NAFLD and its progression to NASH. In this present review, we summarize the current literature regarding the efficacy of the aforementioned category of drugs on anthropometric, laboratory, and histological features of patients with NAFLD. Conclusively, as SGLT2 inhibitors seem to be an appealing therapeutic opportunity for NAFLD management, we identify the open issues and questions to be addressed in order to clarify the impact in choosing antidiabetic medication to treat NAFLD patients associated with T2DM.

Significance of Circulating Cell-Free DNA Species in Non-Alcoholic Fatty Liver Disease.

The pathogenetic mechanisms involved in the progression of non-alcoholic fatty liver disease (NAFLD) have not been completely elucidated, while the significance of circulating cell-free DNA (cf-DNA) species has been rarely evaluated in NAFLD. Herein, we assessed the serum levels of cf-DNA species in NAFLD patients and investigated their potential associations with patients' characteristics and severity of liver disease. Forty-nine adult patients with NAFLD of any stage were included in this cohort study. Cf-DNA was isolated from patients' sera and the levels of several distinct cf-DNA species including total cf-DNA, gene-coding cf-DNA, Alu repeat sequences, mitochondrial DNA copies and 5-methyl-2'-deoxycytidine were determined. Cirrhotic compared to non-cirrhotic patients had significantly lower serum levels of cf-DNA and RNAse P coding DNA as well as higher expression of 5-methyl-2'-deoxycytidine. After adjustment for the significant clinico-epidemiological factors, lower serum levels of cf-DNA or RNAse P were independently associated with the presence of cirrhosis. Serum levels of total and gene-coding DNA are associated with the presence of cirrhosis in NAFLD patients regardless of clinical or epidemiological parameters and may therefore be used as a screening tool for NAFLD progression.

Prevalence and impact on the outcome of myosteatosis in patients with cirrhosis: a systematic review and meta-analysis.

BACKGROUND: Myosteatosis in cirrhotic patients has been evaluated in limited studies with conflicting results and no systematic review or meta-analysis have been performed in this setting. METHODS: We searched for all articles published until June 2023 to evaluate the prevalence of myosteatosis in cirrhosis and chronic liver disease. RESULTS: Seventeen studies focused on cirrhosis and five studies in patients with chronic liver disease were included: the overall pooled prevalence of myosteatosis was 46% [95% Confidence Interval (CI) 36-57%] and 33% (95% CI 15-59%), respectively (p = 0.35). Among the studies with cirrhosis, the prevalence of myosteatosis was higher in those using the body mass index-based definition of myosteatosis (56%), than gender-based (36%) or other criteria (21%) (p < 0.01); was higher in women than in men (61% vs 45%), in Child-Pugh class C than A or B (57% vs 49% vs 50%), in non-alcoholic fatty liver disease (NAFLD)- than viral-associated cirrhosis (57% vs 43%), but these differences were not statistically significant (p > 0.05). Cirrhotic patients with myosteatosis, compared to those without myosteatosis, had more frequently a previous history of hepatic encephalopathy (32% vs 15%, p = 0.04), less frequently a previous history of variceal bleeding (46% vs 65%, p < 0.01), were more likely to suffer from diabetes mellitus (27% vs 18%, p < 0.01), while they had higher mortality rates (40% vs 14%, p = 0.02). CONCLUSION: Myosteatosis is highly prevalent in patients with cirrhosis, particularly in those with NAFLD-associated cirrhosis. Myosteatosis is associated with hepatic encephalopathy, while it seems to have a negative impact on the outcome.

Metabolic-Associated Fatty Liver Disease and Sarcopenia.

The current evidence indicates a strong association between sarcopenia, the loss of muscle mass and strength, and metabolic-associated fatty liver disease (MAFLD). The two entities share many common pathophysiologic mechanisms, and their coexistence may result in higher rates of morbidity and mortality. Therefore, given their increasing incidence in the modern world, there is a need for a better understanding of the liver-muscle axis for early identification of sarcopenia in patients with MAFLD and vice versa. This review aims at presenting current data regarding the correlation between sarcopenia and MAFLD, the associated comorbidities, and the need for effective therapies.

Aspartate aminotransferase-to-platelet ratio index can predict the outcome in patients with stable decompensated cirrhosis.

Background: Platelet (PLT)-based biomarkers have been studied for the evaluation of liver fibrosis and cirrhosis. There are no data regarding their prognostic significance in decompensated cirrhosis. Methods: We studied 525 stable decompensated patients from the 2 Greek transplant centers. We measured PLT values, mean PLT volume (MPV), red cell distribution width, γ-globulins, and calculated PLT-based scores: aspartate aminotransferase-to-PLT ratio index (APRI), γ-globulin-to-PLT model, and γ-glutamyl transpeptidase-to-PLT ratio (GPR). Results: We followed our cohort for 12 (range: 1-84) months. Baseline mean model for end-stage liver disease (MELD) and Child-Turcotte-Pugh (CTP) scores were 15±6 and 8±2, respectively. On univariate analysis, MPV/PLT (hazard ratio [HR] 3.75, 95% confidence interval [CI] 1-14.5; P=0.05), APRI (HR 1.03, 95%CI 1.006-1.06; P=0.016), GPR (HR 1.096, 95%CI 1.016-1.182; P=0.017) were significantly associated with our patients' outcome (survival vs. death or liver transplantation). In a multivariate model without MELD and CTP scores, APRI was the only significant factor associated with the outcome (HR 1.054, 95%CI 1.009-1.101; P=0.018). APRI had good discriminative ability for the outcome (area under the curve 0.723 vs. 0.675 and 0.656 for MELD and CTP scores, respectively). The optimal cutoff point was 1.3 (sensitivity 71%, specificity 65%). There were 200 patients (38%) with APRI scores <1.3 who had better survival than patients with APRI >1.3 (log rank 22.4, P<0.001). Conclusions: This study found a prognostic role for APRI in stable decompensated cirrhosis, regardless of the underlying etiology of chronic liver disease. This suggests new perspectives for PLT-based noninvasive scores to discriminate patients' outcomes.

Significance of Circulating Cell-Free DNA Biomarkers in HBeAg-Negative Chronic Hepatitis B Virus Infection and Their Changes after Treatment Initiation.

BACKGROUND: Chronic hepatitis B virus (HBV) infection is a common chronic liver disease that is closely associated with increased morbidity and mortality. Circulating cell-free DNA (cf-DNA) and global DNA methylation, expressed as circulating levels of 5-methyl-2'-deoxycytidine, are increasingly used to monitor chronic inflammatory diseases of several etiologies. This study attempts to investigate the serum levels of circulating cf-DNA and 5-methyl-2'-deoxycytidine in HBeAg-negative patients with chronic infection (carriers) and chronic hepatitis B (CHB), as well as their changes after treatment initiation in CHB. METHODS: Serum samples from a total of 61 HBeAg-negative patients (30 carriers and 31 CHB patients) were included in order to quantify the levels of circulating cf-DNA and 5-methyl-2'-deoxycytidine. In addition, serum samples from 17 CHB patients in complete virological and biochemical remission after initiation of treatment with a nucleos(t)ide analogue were included. RESULTS: Circulating cf-DNA concentration was significantly increased after the initiation of treatment (15 vs. 10 ng/mL, p = 0.022). There was a trend in higher mean levels of circulating 5-methyl-2'-deoxycytidine in carriers compared to CHB patients (211.02 vs. 175.66 ng/mL, p = 0.089), as well as a trend in increasing 5-methyl-2'-deoxycytidine levels after treatment initiation in CHB patients compared to pre-treatment levels (215 vs. 173 ng/mL, p = 0.079). CONCLUSIONS: Both circulating levels of cf-DNA and 5-methyl-2'-deoxycytidine might be useful biomarkers in order to monitor liver disease activity and response to antiviral treatment in HBeAg-negative chronic HBV patients, but further studies are essential in order to validate these intriguing findings.

Non-alcoholic fatty liver disease and hepatocellular carcinoma: Clinical challenges of an intriguing link.

Non-alcoholic fatty liver disease (NAFLD) has emerged as the most common liver disorder worldwide mainly attributed to the epidemic spread of obesity and type 2 diabetes mellitus. Although it is considered a benign disease, NAFLD can progress to non-alcoholic steatohepatitis, liver cirrhosis and hepatocellular carcinoma (HCC). Most data regarding the epidemiology of NAFLD-related HCC are derived from cohort and population studies and show that its incidence is increasing as well as it is likely to emerge as the leading indication for liver transplantation, especially in the Western World. Although cirrhosis constitutes the main risk factor for HCC development, in patients with NAFLD, HCC can arise in the absence of cirrhosis, indicating specific carcinogenic molecular pathways. Since NAFLD as an underlying liver disease for HCC is often underdiagnosed due to lack of sufficient surveillance in this population, NAFLD-HCC patients are at advanced HCC stage at the time of diagnosis making the management of those patients clinically challenging and affecting their prognostic outcomes. In this current review, we summarize the latest literature on the epidemiology, other than liver cirrhosis-pathogenesis, risk factors and prognosis of NAFLD-HCC patients. Finally, we emphasize the prevention of the development of NAFLD-associated HCC and we provide some insight into the open questions and issues regarding the appropriate surveillance policies for those patients.

Frailty in metabolic syndrome, focusing on nonalcoholic fatty liver disease.

In recent years, frailty has been increasingly recognized among researchers of distinct medical specialties worldwide. Frailty comprises a complex of multisystemic physiological decline, reduced physiologic reserve, and vulnerability to stressors. Frail people tend to have a shorter lifespan and greater disability, morbidity and mortality. In the field of hepatology, frailty is identified in nearly 50% of patients who have cirrhosis of any cause. The most predominant cause of chronic liver disease is nonalcoholic fatty liver disease (NAFLD), considered as the hepatic manifestation of the metabolic syndrome (MetS). Although it is viewed as a benign disease, it may progress to nonalcoholic steatohepatitis (NASH), characterized by the additional emergence of inflammation and hepatocyte ballooning, with or without fibrosis. During the progression of NAFLD to NASH and liver cirrhosis, NAFLD patients present sarcopenia along with lower skeletal muscle strength and function. Moreover, aging and the increased prevalence of comorbidities further exacerbate their physical performance. The aforementioned features are strongly associated with the frailty phenotype, implying that the latter could be associated with both MetS and NAFLD. Although it is a relatively new topic of research interest, in this review we aim to provide a synopsis of the current literature dealing with the interplay between frailty and MetS, and to shed more light on the association between NAFLD and frailty. Finally, we discuss the potential pathophysiological mechanisms linking the distinct features of MetS and NAFLD with aspects of the frailty phenotype.

The role of fibroblast growth factor 19 in the pathogenesis of nonalcoholic fatty liver disease.

INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) has emerged as the predominant cause of chronic liver injury worldwide. Bile acids and their receptors are profoundly implicated in the pathogenesis of NAFLD and its progression to nonalcoholic steatohepatitis and cirrhosis. AREAS COVERED: We conducted extensive literature search using PubMed database, and we summarized the relevant literature. We provided an overview of the fibroblast growth factor 19 (FGF-19)-farnesoid X receptor (FXR) axis and summarized the latest findings derived from animal and human studies concerning the impact of FGF-19 on NAFLD. EXPERT OPINION: FGF-19, a nutritionally regulated endocrine post-prandial hormone, governs bile acid metabolism, lipid oxidation, lipogenesis, and energy homeostasis. As no approved medication for NAFLD exists, FGF-19 seems to be a propitious therapeutic opportunity for NAFLD, since its administration was associated with ameliorated results in hepatic steatosis, liver inflammation and fibrosis. Furthermore, promising results have been derived from clinical trials concerning the beneficial efficacy of FGF-19 on histological findings and laboratory parameters of NAFLD. However, we should bear in mind the pleiotropic effects of FGF-19 on various metabolically active tissues along with its potential tumorigenic reservoir. Further clinical research is required to determine the clinical application of FGF-19-based therapies on NAFLD.

Alcohol consumption in patients with nonalcoholic fatty liver disease: yes, or no?

Excessive alcohol intake is an established risk factor for chronic liver disease. At the same time, moderate alcohol intake appears to reduce cardiovascular morbidity. Accordingly, recommendations for alcohol intake in patients with nonalcoholic fatty liver disease (NAFLD), who are at increased risk for liver-related and cardiovascular events, are a point of debate. Some studies have shown beneficial effects of alcohol on cardiovascular and overall mortality in this specific subset of patients. Nonetheless, even light alcohol intake appears to aggravate liver disease and increase the risk of hepatocellular cancer. Therefore, patients with nonalcoholic steatohepatitis or advanced fibrosis should be advised against consuming alcohol. On the other hand, only light alcohol consumption (<10 g/day) might be permitted in patients without significant hepatic fibrosis, provided that they are carefully followed-up. As the research field focusing on NAFLD keeps widening, more prospective studies regarding this specific subject are expected, and may provide a basis for less ambiguous recommendations.

Glucagon-like peptide-1 receptor agonists in non-alcoholic fatty liver disease: An update.

Non-alcoholic fatty liver disease (NAFLD) is the predominant cause of chronic liver disease worldwide. NAFLD progresses in some cases to non-alcoholic steatohepatitis (NASH), which is characterized, in addition to liver fat deposition, by hepatocyte ballooning, inflammation and liver fibrosis, and in some cases may lead to hepatocellular carcinoma. NAFLD prevalence increases along with the rising incidence of type 2 diabetes mellitus (T2DM). Currently, lifestyle interventions and weight loss are used as the major therapeutic strategy in the vast majority of patients with NAFLD. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are used in the management of T2DM and do not have major side effects like hypoglycemia. In patients with NAFLD, the GLP-1 receptor production is down-regulated. Recently, several animal and human studies have emphasized the role of GLP-1RAs in ameliorating liver fat accumulation, alleviating the inflammatory environment and preventing NAFLD progression to NASH. In this review, we summarize the updated literature data on the beneficial effects of GLP-1RAs in NAFLD/NASH. Finally, as GLP-1RAs seem to be an attractive therapeutic option for T2DM patients with concomitant NAFLD, we discuss whether GLP-1RAs should represent the first line pharmacotherapy for these patients.

Nonalcoholic fatty liver disease in lean subjects: Prognosis, outcomes and management.

Nonalcoholic fatty liver disease (NAFLD) accounts for most cases of chronic liver disease worldwide, with an estimated global prevalence of approximately 25% and ranges from simple steatosis to nonalcoholic steatohepatitis and cirrhosis. NAFLD is strongly connected to metabolic syndrome, and for many years, fatty liver was considered to be an exclusive feature of obese patients. However, recent studies have highlighted the presence of NAFLD in non-obese subjects, with or without increased visceral fat or even in lean subjects without increased waist circumference. "Lean NAFLD" is a relatively new concept and there is significant scientific interest in understanding the differences in pathophysiology, prognosis and management compared with NAFLD in overweight/obese patients. In the present editorial, we discuss the clinical and metabolic profiles and outcomes of lean NAFLD compared with both obese NAFLD and lean healthy individuals from Asian and Western countries. Moreover, we shed light to the challenging topic of management of NAFLD in lean subjects since there are no specific guidelines for this population. Finally, we discuss open questions and issues to be addressed in the future in order to categorize NAFLD patients into lean and non-lean cohorts.