A global research priority agenda to advance public health responses to fatty liver disease

Background & aims An estimated 38% of adults worldwide have non-alcoholic fatty liver disease (NAFLD). From individual impacts to widespread public health and economic consequences, the implications of this disease are profound. This study aimed to develop an aligned, prioritised fatty liver disease research agenda for the global health community. Methods Nine co-chairs drafted initial research priorities, subsequently reviewed by 40 core authors and debated during a three-day in-person meeting. Following a Delphi methodology, over two rounds, a large panel (R1 n = 344, R2 n = 288) reviewed the priorities, via Qualtrics XM, indicating agreement using a four-point Likert-scale and providing written feedback. The core group revised the draft priorities between rounds. In R2, panellists also ranked the priorities within six domains: epidemiology, models of care, treatment and care, education and awareness, patient and community perspectives, and leadership and public health policy. Results The consensus-built fatty liver disease research agenda encompasses 28 priorities. The mean percentage of ‘agree’ responses increased from 78.3 in R1 to 81.1 in R2. Five priorities received unanimous combined agreement (‘agree’ + ‘somewhat agree’); the remaining 23 priorities had >90% combined agreement. While all but one of the priorities exhibited at least a super-majority of agreement (>66.7% ‘agree’), 13 priorities had 90% combined agreement. Conclusions Adopting this multidisciplinary consensus-built research priorities agenda can deliver a step-change in addressing fatty liver disease, mitigating against its individual and societal harms and proactively altering its natural history through prevention, identification, treatment, and care. This agenda should catalyse the global health community’s efforts to advance and accelerate responses to this widespread and fast-growing public health threat. Impact and implications An estimated 38% of adults and 13% of children and adolescents worldwide have fatty liver disease, making it the most prevalent liver disease in history. Despite substantial scientific progress in the past three decades, the burden continues to grow, with an urgent need to advance understanding of how to prevent, manage, and treat the disease. Through a global consensus process, a multidisciplinary group agreed on 28 research priorities covering a broad range of themes, from disease burden, treatment, and health system responses to awareness and policy. The findings have relevance for clinical and non-clinical researchers as well as funders working on fatty liver disease and non-communicable diseases more broadly, setting out a prioritised, ranked research agenda for turning the tide on this fast-growing public health threat

Histopathology of nonalcoholic fatty liver disease

Histological analysis of liver biopsies remains a standard against which other methods of assessment for the presence and amount of hepatic injury due to nonalcoholic fatty liver disease (NAFLD) are measured. Histological evaluation remains the sole method of distinguishing steatosis from advanced forms of NAFLD, i.e. nonalcoholic steatohepatitis (NASH) and fibrosis. Included in the lesions of NAFLD are steatosis, lobular and portal inflammation, hepatocyte injury in the forms of ballooning and apoptosis, and fibrosis. However, patterns of these lesions are as distinguishing as the lesions themselves. Liver injury in adults and children due to NAFLD may have different histological patterns. In this review, the rationale for liver biopsy, as well as the histopathological lesions, the microscopically observable patterns of injury, and the differential diagnoses of NAFLD and NASH are discussed. © 2010 Baishideng

Editorial: Exercise for NAFLD: Does intensity matter

Currently, there are no established means for the prevention or treatment of non-alcoholic steatohepatitis (NASH) despite our increasing understanding of nonalcoholic fatty liver disease (NAFLD) pathogenesis implicating insulin resistance (IR) as a key factor and highlighting the central role of lipotoxic liver injury in the development of NASH. Lifestyle interventions aiming at decreasing IR and preventing lipotoxicity, including weight loss, diet, and physical exercise, are in the frontline for NASH patient management. Physical activity may ameliorate IR, maintain weight loss, and improve liver histology in NASH patients. However, there are no recognized criteria for the optimal intensity, duration, or total volume of exercise needed to obtain these beneficial effects. In this issue of the American Journal of Gastroenterology, Kistler and colleagues show that vigorous, but not moderate exercise, nor total duration or volume of physical activity, is related to decreased odds of having NASH or advanced fibrosis. Prospective studies using the objective criteria of physical activity, addressing the role of concurrent weight loss, and assessing individual histological features are needed to further clarify the effects of exercise intensity on NAFLD histology. © 2011 by the American College of Gastroenterology

E2F transcription factors and digestive system malignancies: How much do we know?

E2F family of transcription factors regulates various cellular functions related to cell cycle and apoptosis. Its individual members have traditionally been classified into activators and repressors, based on in vitro studies. However their contribution in human cancer is more complicated and difficult to predict. We review current knowledge on the expression of E2Fs in digestive system malignancies and its clinical implications for patient prognosis and treatment. E2F1, the most extensively studied member and the only one with prognostic value, exhibits a tumor-suppressing activity in esophageal, gastric and colorectal adenocarcinoma, and in hepatocellular carcinoma (HCC), whereas in pancreatic ductal adenocarcinoma and esophageal squamous cell carcinoma may function as a tumorpromoter. In the latter malignancies, E2F1 immunohistochemical expression has been correlated with higher tumor grade and worse patient survival, whereas in esophageal, gastric and colorectal adenocarcinomas is a marker of increased patient survival. E2F2 has only been studied in colorectal cancer, where its role is not considered significant. E2F4's role in colorectal, gastric and hepatic carcinogenesis is tumor-promoting. E2F8 is strongly upregulated in human HCC, thus possibly contributing to hepatocarcinogenesis. Adenoviral transfer of E2F as gene therapy to sensitize pancreatic cancer cells for chemotherapeutic agents has been used in experimental studies. Other therapeutic strategies are yet to be developed, but it appears that targeted approaches using E2F-agonists or antagonists should take into account the tissue-dependent function of each E2F member. Further understanding of E2Fs' contribution in cellular functions in vivo would help clarify their role in carcinogenesis. © 2013 Baishideng. All rights reserved

Inflammation in nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) describes a range of disorders characterized by excess accumulation of triglyceride within the liver. While simple steatosis may be clinically stable, nonalcoholic steatohepatitis (NASH) can be progressive. Inflammation is believed to be the driving force behind NASH and the progression to fibrosis and subsequent cirrhosis. This article will review and interpret the current literature in an attempt to expand our understanding of the environmental and genetic causes of inflammation and its effects in NAFLD. © 2011 Expert Reviews Ltd

Fatty liver disease and hepatocellular carcinoma: The pathologist’s view

Chronic alcohol misuse and progressed nonalcoholic fatty liver disease (NAFLD) due to the metabolic syndrome and resulting to nonalcoholic steatohepatitis (NASH) are prime causes of hepatocellular carcinoma (HCC) in Western industrialized countries. The incidence of HCC in NASH-cirrhosis is lower than that of HCC occuring in HCV-related or alcoholic cirrhosis. Up to 20% of cases of alcohol-associated HCC may develop in pre-cirrhotic liver while HCC is also increasingly recognised in pre-cirrhotic NASH raising questions on appropriate surveillance measures for these patient populations. The recently described steatohepatitic subtype of HCC presents with higher frequency in NAFLD compared to alcoholic liver disease (ALD) patients. This review will mainly focus on histopathology and summarize current data on the epidemiology, pathogenesis, diagnosis and management of NAFLD- and ALD-related HCC. © Springer Nature Switzerland AG 2018

Tityus: A forgotten myth of liver regeneration

The ancient Greek myth of Tityus is related to liver regeneration in the same way as the well known myth of Prometheus is. Depictions of the punishment of Prometheus are frequently used by lecturers on liver regeneration; however, Tityus remains unknown despite the fact that he received the same punishment and his myth could also be used as a paradigm for the organ's extraordinary ability to regenerate. Nevertheless, there is no convincing evidence that ancient Greeks had any specific knowledge about liver regeneration, a concept introduced in the early 19th century. We describe and analyze the myth of Tityus and compare it to the myth of Prometheus. We also explore artistic and literary links and summarize recent scientific data on the mechanisms of liver regeneration. Finally, we highlight links of the legend of Tityus with other sciences. © 2010 European Association for the Study of the Liver

Evaluation of liver fibrosis: “Something old, something new…”

Hepatic fibrogenesis may gradually result to cirrhosis due to the accumulation of extracellular matrix components as a response to liver injury. Thus, therapeutic decisions in chronic liver disease, regardless of the cause, should first and foremost be guided by an accurate quantification of hepatic fibrosis. Detection and assessment of the extent of hepatic fibrosis represent a challenge in modern Hepatology. Although traditional histological staging systems remain the “best standard”, they are not able to quantify liver fibrosis as a dynamic process and may not accurately substage cirrhosis. This review aims to compare the currently used non-invasive methods of measuring liver fibrosis and provide an update in current tissue-based digital techniques developed for this purpose, that may prove of value in daily clinical practice. © 2016 Hellenic Society of Gastroenterology