Separating the apples from the oranges: from NAFLD heterogeneity to personalized medicine

Recently, Arrese and Colleagues have published a review article entitled, "Insights into Nonalcoholic Fatty-Liver Disease (NAFLD) Heterogeneity" (Semin Liver Dis. 2021;41:421-34. doi: 10.1055/s-0041-1730927). This milestone publication clearly and exhaustively explains the multitude of pathogenic pathways involved in the development and progression of disease eventually conducive to heterogeneous clinical phenotypes and different disease outcomes. The present commentary first briefly discusses the biological grounds of NAFLD heterogeneity and then illustrates the work by Arrese et al. In conclusion, the presently adopted nomenclatures appear inadequate in rendering the complexity of disease in the individual patient. In order to adopt the principles of personalized care, what remains to be done is to propose and validate a simple and accurate classification system. This should give full consideration to the principal disease modifiers and should shape a scheme to be adopted in both clinical practice and in the research arena. Care should be taken to not neglect the systemic nature of disease

Principles of risk stratification in nonalcoholic fatty liver disease. A narrative review emphasizing non-invasive strategies

Nonalcoholic fatty liver disease (NAFLD) is an umbrella definition that describes the ectopic deposition of fat within the liver that occurs in the absence of inciting factors other than the metabolic syndrome and its individual features. NAFLD has a multi-factorial pathogenesis which determines heterogeneous clinical phenotypes and variable natural course spanning from liver-related (steatohepatitis, fibrosis, cirrhosis, hepatocellular carcinoma) to extrahepatic outcomes (cardio-metabolic and cancer). This narrative review article leverages the key aspects of disease natural history as the background information to discuss studies that may inform strategies to risk-stratify NAFLD patients. Evaluation of hepatic fibrosis with non-invasive tools, including blood-based biomarkers and imaging-based elastometry techniques, seemingly retains the core information useful to predict the heterogeneous outcomes listed above. Additionally, genetic testing and metabolomic profiles may also be utilized to this end. In conclusion, a comprehensive understanding of the variable hepatic, cardio-metabolic and cancer outcomes of NAFLD may enable physicians and researchers to risk-stratify and accurately identify the multilayered prognosis of NAFLD individuals while also defining homogeneous patient subsets to enroll in clinical trials

NAFLD in Some Common Endocrine Diseases: Prevalence, Pathophysiology, and Principles of Diagnosis and Management

Secondary nonalcoholic fatty liver disease (NAFLD) defines those complex pathophysiological and clinical consequences that ensue when the liver becomes an ectopic site of lipid storage owing to reasons other than its mutual association with the metabolic syndrome. Disorders affecting gonadal hormones, thyroid hormones, or growth hormones (GH) may cause secondary forms of NAFLD, which exhibit specific pathophysiologic features and, in theory, the possibility to receive an effective treatment. Here, we critically discuss epidemiological and pathophysiological features, as well as principles of diagnosis and management of some common endocrine diseases, such as polycystic ovary syndrome (PCOS), hypothyroidism, hypogonadism, and GH deficiency. Collectively, these forms of NAFLD secondary to specific endocrine derangements may be envisaged as a naturally occurring disease model of NAFLD in humans. Improved understanding of such endocrine secondary forms of NAFLD promises to disclose novel clinical associations and innovative therapeutic approaches, which may potentially be applied also to selected cases of primary NAFLD

Nonalcoholic fatty liver disease and COPD: is it time to cross the diaphragm?

Editorial of "Nonalcoholic fatty liver disease in chronic obstructive pulmonary disease.

NAFLD: Is There Anything New under the Sun?

Nonalcoholic fatty liver disease (NAFLD) is an "umbrella" definition that encompasses a spectrum of histological liver changes ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) with/without fibrosis, "cryptogenic" cirrhosis, and hepatocellular carcinoma (HCC), occurring in a dysmetabolic milieu, though in the absence of excessive alcohol consumption and other competing etiologies of chronic liver disease [1].[...]

The Role of Nuclear Receptors in the Pathophysiology, Natural Course, and Drug Treatment of NAFLD in Humans.

Nonalcoholic fatty liver disease (NAFLD) describes steatosis, nonalcoholic steatohepatitis with or without fibrosis, and hepatocellular carcinoma, namely the entire alcohol-like spectrum of liver disease though observed in the nonalcoholic, dysmetabolic, individual free of competing causes of liver disease. NAFLD, which is a major public health issue, exhibits intrahepatic triglyceride storage giving rise to lipotoxicity. Nuclear receptors (NRs) are transcriptional factors which, activated by ligands, are master regulators of metabolism and also have intricate connections with circadian control accounting for cyclical patterns in the metabolic fate of nutrients. Several transcription factors, such as peroxisome proliferator-activated receptors, liver X receptors, farnesoid X receptors, and their molecular cascades, finely regulate energetic fluxes and metabolic pathways. Dysregulation of such pathways is heavily implicated in those metabolic derangements characterizing insulin resistance and metabolic syndrome and in the histogenesis of progressive NAFLD forms. We review the role of selected NRs in NAFLD pathogenesis. Secondly, we analyze the role of NRs in the natural history of human NAFLD. Next, we discuss the results observed in humans following administration of drug agonists or antagonists of the NRs pathogenically involved in NAFLD. Finally, general principles of treatment and lines of research in human NAFLD are briefly examined

Sofosbuvir-based therapy cures hepatitis C virus infection after prior treatment failures in a patient with concurrent lymphoma

We report on the first well-tolerated and successful use of sofosbuvir-based therapy in a patient in whom chronic infection with hepatitis C had preceded the development of B-cell non-Hodgkin's lymphoma. The patient had previously failed numerous attempts to clear the hepatitis C virus with traditional antiviral schedules. We demonstrate that sofosbuvir-based therapy resulted in cure of hepatitis C in a patient who had relapsed during combination therapy with an NS5A inhibitor, an NS3 protease inhibitor and ribavirin, as well as treatment failures to multiple courses of interferon-based therapy. This report also suggests that eradication of hepatitis C virus may result in the short-term prevention of B-cell non-Hodgkin's lymphoma relapse. The findings from our case require further validation in future cohorts of patients

"Not all forms of NAFLD were created equal". Do metabolic syndrome-related NAFLD and PNPLA3-related NAFLD exert a variable impact on the risk of early carotid atherosclerosis?

On this background of evidence, the results of the study by Di Costanzo et al. [8] provide further support to the view that the aetiology of NAFLD is multifactorial and this disease may be caused by common genetic variants. One of these, the PNPLA-3 variant, is associated with higher liver fat content and increased risk of NASH, but is not systematically associated with insulin resistance and MetS traits [4,5]. This study adds a further critical piece of information by suggesting that the MetS-related NAFLD and the PNPLA3-related NAFLD may differentially affect the risk of subclinical atherosclerosis and perhaps of clinical CVD [8]. However, it does not detract from the notion that NAFLD, especially NASH with varying degrees of fibrosis, may directly contribute to the development and progression of CVD [2,3,9], because genetic NAFLD is a subtly different disease and less than 15% of European patients with NAFLD have the PNPLA3 GG genotype [4,5]. Furthermore, as previously mentioned, the few observational studies that have assessed the association between the PNPLA3 rs738409 gene polymorphism and risk of atherosclerosis have provided conflicting results (as summarized in Table 1

Nonalcoholic fatty liver disease: Evolving paradigms

In the last years new evidence has accumulated on nonalcoholic fatty liver disease (NAFLD) challenging the paradigms that had been holding the scene over the previous 30 years. NAFLD has such an epidemic prevalence as to make it impossible to screen general population looking for NAFLD cases. Conversely, focusing on those cohorts of individuals exposed to the highest risk of NAFLD could be a more rational approach. NAFLD, which can be diagnosed with either non-invasive strategies or through liver biopsy, is a pathogenically complex and clinically heterogeneous disease. The existence of metabolic as opposed to genetic-associated disease, notably including "lean NAFLD" has recently been recognized. Moreover, NAFLD is a systemic condition, featuring metabolic, cardiovascular and (hepatic/extrahepatic) cancer risk. Among the clinico-laboratory features of NAFLD we discuss hyperuricemia, insulin resistance, atherosclerosis, gallstones, psoriasis and selected endocrine derangements. NAFLD is a precursor of type 2 diabetes (T2D) and metabolic syndrome and progressive liver disease develops in T2D patients in whom the course of disease is worsened by NAFLD. Finally, lifestyle changes and drug treatment options to be implemented in the individual patient are also critically discussed. In conclusion, this review emphasizes the new concepts on clinical and pathogenic heterogeneity of NAFLD, a systemic disorder with a multifactorial pathogenesis and protean clinical manifestations. It is highly prevalent in certain cohorts of individuals who are thus potentially amenable to selective screening strategies, intensive follow-up schedules for early identification of liver-related and extrahepatic complications and in whom earlier and more aggressive treatment schedules should be carried out whenever possible