Betatrophin Levels Are Related to the Early Histological Findings in Nonalcoholic Fatty Liver Disease

Circulating angiopoietin-like protein 8 (ANGPTL8) and steatotic liver disease related to metabolic dysfunction: an updated systematic review and meta-analysis

Background

Steatotic liver disease related to metabolic dysfunction is the most common cause of chronic liver disease globally. The spectrum of this condition includes steatosis and steatohepatitis and was previously referred to as non-alcoholic fatty liver disease (NAFLD) but has been renamed as metabolic dysfunction-associated fatty liver disease (MAFLD) and more recently as metabolic dysfunction-associated steatotic liver disease (MASLD). Angiopoietin-like protein 8 (ANGPTL8), also known as betatrophin or lipasin, regulates triglycerides and has emerged as a potential novel biomarker for steatosis/steatohepatitis. Therefore, this systematic review aimed to identify and synthesize the evidence on the possible association of circulating ANGPTL8 concentrations with NAFLD, MAFLD or MASLD.

Methods

PubMed/MEDLINE, Cochrane Library, EMBASE, and Web of Science were searched for studies published in English reporting circulating ANGPTL8 concentrations in adults with NAFLD or MAFLD or MASLD and controls. A meta-analysis was performed, reporting the standardized mean difference (SMD) of circulating ANGPTL8 concentrations between these two groups. Study quality and risk of bias were assessed using the NIH quality assessment tool and RoBANS 2, respectively.

Results

Of the 104 identified publications, eight studies were eligible for this systematic review, whilst seven were also eligible for meta-analysis (543 NAFLD or MAFLD cases vs. 352 controls). Circulating ANGPTL8 concentrations were significantly higher in patients with NAFLD or MAFLD compared with controls (SMD: 0.62, 95%CI: 0.28-0.97; p<0.001). Considerable heterogeneity was noted among these studies, with six studies having high risk of bias in at least one RoBANS 2 domain.

Conclusion

These findings present up-to-date comprehensive evidence indicating that adults with steatotic liver disease related to metabolic dysfunction exhibit higher circulating ANGPTL8 concentrations compared with controls. Given the need for novel screening/diagnostic biomarkers for steatosis/steatohepatitis, as well for additional drug targets, large and prospective studies are required to confirm this association and explore its temporal direction, particularly under the new MASLD diagnosis/term.

From NAFLD to MASLD: Meta-analysis and systematic review of NAFLD patients in Turkiye in terms of metabolic profile and MASLD potential

Non-alcoholic Fatty Liver Disease (NAFLD) is both a cause and a consequence of metabolic disturbances. Consequently, the disease term has recently changed to Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD). Turkiye is one of the leading countries with high incidences of diseases such as diabetes, obesity, metabolic syndrome, and fatty liver. This study aims to identify the metabolic parameters and MASLD potential of NAFLD in Turkiye. All NAFLD studies conducted in Turkiye were systematically searched using the keywords "fatty liver disease" AND " Turkiye " on PubMed, Scopus, and Web of Science databases. A total of 2653 articles were scanned, and 120 studies were eligible for meta-analysis. The metabolic parameters were meta-analyzed from a broad perspective. According to the meta-analysis results, there were significant increases in waist circumferences (mean difference: 10.90, p<0.00001), HOMA-IR (mean difference: 2.13, p<0.00001), aspartate aminotransferase (AST) (mean difference: 17.82, p<0.00001), systolic blood pressure (SBP) (mean difference: 5.86, p<0.00001), and C-reactive protein (CRP) levels (mean difference: 0.95, p<0.00001). These parameters are representative biochemical findings of disturbed glucose metabolism, lipid profile, blood pressure, and acute phase response mechanisms. Furthermore, the analysis of all related parameters commonly found among the articles confirmed these metabolic dysfunctions. NAFLD is a metabolic disease that encompasses multiple pathways related to glucose and lipid metabolism, vascular function, inflammation, and acute phase responses. Additionally, our results suggest that Turkish NAFLD patients identified in previous studies mostly have MASLD. This is the first meta-analysis study indicating changes in metabolism-related parameters with a cumulative meta-analysis of all Turkish NAFLD studies.

Plasma insulin is required for the increase in plasma angiopoietin-like protein 8 in response to nutrient ingestion

BACKGROUND

Plasma levels of angiopoietin-like protein 8 (ANGPTL8) are regulated by feeding and they increase following glucose ingestion. Because both plasma glucose and insulin increase following food ingestion, we aimed to determine whether the increase in plasma insulin and glucose or both are responsible for the increase in ANGPTL8 levels.

METHODS

ANGPTL8 levels were measured in 30 subjects, 14 with impaired fasting glucose (IFG), and 16 with normal fasting glucose (NFG); the subjects received 75g glucose oral Glucose tolerance test (OGTT), multistep euglycaemic hyperinsulinemic clamp and hyperglycaemic clamp with pancreatic clamp.

RESULTS

Subjects with IFG had significantly higher ANGPTL8 than NGT subjects during the fasting state (p < 0.05). During the OGTT, plasma ANGPTL8 concentration increased by 62% above the fasting level (p < 0.0001), and the increase above fasting in ANGPTL8 levels was similar in NFG and IFG individuals. During the multistep insulin clamp, there was a dose-dependent increase in plasma ANGPTL8 concentration. During the 2-step hyperglycaemic clamp, the rise in plasma glucose concentration failed to cause any change in the plasma ANGPTL8 concentration from baseline.

CONCLUSIONS

In response to nutrient ingestion, ANGPTL8 level increased due to increased plasma insulin concentration, not to the rise in plasma glucose. The incremental increase above baseline in plasma ANGLPTL8 during OGTT was comparable between people with normal glucose tolerance and IFG.

Contribution of organokines in the development of NAFLD/NASH associated hepatocellular carcinoma

Globally the incidence of hepatocellular carcinoma (HCC) is on an upsurge. Evidence is accumulating that liver disorders like nonalcoholic fatty liver disease (NAFLD) and its more progressive form nonalcoholic steatohepatitis (NASH) are associated with increased risk of developing HCC. NAFLD has a prevalence of about 25% and 50%-90% in obese population. With the growing burden of obesity epidemic worldwide, HCC presents a major healthcare burden. While cirrhosis is one of the major risk factors of HCC, available literature suggests that NAFLD/NASH associated HCC also develops in minimum or noncirrhotic livers. Therefore, there is an urgent need to understand the pathogenesis and risk factors associated with NAFLD and NASH related HCC that would help in early diagnosis and favorable prognosis of HCC secondary to NAFLD. Adipokines, hepatokines and myokines are factors secreted by adipocytes, hepatocytes and myocytes, respectively, playing essential roles in cellular homeostasis, energy balance and metabolism with autocrine, paracrine and endocrine effects. In this review, we endeavor to focus on the role of these organokines in the pathogenesis of NAFLD/NASH and its progression to HCC to augment the understanding of the factors stimulating hepatocytes to acquire a malignant phenotype. This shall aid in the development of novel therapeutic strategies and tools for early diagnosis of NAFLD/NASH and HCC.

Non-alcoholic fatty liver disease, metabolic syndrome, and type 2 diabetes mellitus: where do we stand today?

Non-alcoholic fatty liver disease (NAFLD), metabolic syndrome (MetS), and type 2 diabetes (T2DM) are metabolic disorders that belong to a highly prevalent disease cluster with a significant impact on public health worldwide. MetS is a complex condition characterized by metabolism perturbations that include glucose intolerance, insulin resistance, dyslipidaemia, associated pro-inflammatory state, and arterial hypertension. Because the components of MetS commonly co-occur, the management of these disorders cannot be considered separate issues. Thus NAFLD, recognized as a hepatic manifestation of MetS, is frequently associated with T2DM. This review analyses the underlying connections between these diseases and the risks associated with their co-occurrence. The effective management of NAFLD associated with MetS and T2DM involves an early diagnosis and optimal treatment of each condition leading to improvement in glycaemic and lipid regulation, liver steatosis, and arterial hypertension. The net effect of such treatment is the prevention of atherosclerotic cardiovascular diseases and liver fibrosis.

Plasma Oxylipin Profile Discriminates Ethnicities in Subjects with Non-Alcoholic Steatohepatitis: An Exploratory Analysis

Non-alcoholic fatty liver disease (NAFLD) is a common liver pathology that includes steatosis, or non-alcoholic fatty liver (NAFL), and non-alcoholic steatohepatitis (NASH). Without a clear pathophysiological mechanism, it affects Hispanics disproportionately compared to other ethnicities. Polyunsaturated fatty acids (PUFAs) and inflammatory lipid mediators including oxylipin (OXL) and endocannabinoid (eCB) are altered in NAFLD and thought to contribute to its pathogenesis. However, the existence of ethnicity-related differences is not clear. We employed targeted lipidomic profiling for plasma PUFAs, non-esterified OXLs and eCBs in White Hispanics (HIS, n = 10) and Caucasians (CAU, n = 8) with biopsy-confirmed NAFL, compared with healthy control subjects (HC; n = 14 HIS; n = 8 CAU). NAFLD was associated with diminished long chain PUFA in HIS, independent of histological severity. Differences in plasma OXLs and eCBs characterized ethnicities in NASH, with lower arachidonic acid derived OXLs observed in HIS. The secondary analysis comparing ethnicities within NASH (n = 12 HIS; n = 17 CAU), confirms these ethnicity-related differences and suggests lower lipoxygenase(s) and higher soluble epoxide hydrolase(s) activities in HIS compared to CAU. While causes are not clear, these lipidomic differences might be with implications for NAFLD severity and are worth further investigation. We provide preliminary data indicating ethnicity-specific lipidomic signature characterizes NASH which requires further validation.