Non-alcoholic fatty liver disease and thrombocytopenia IV: its association with granulocytopenia

Deep metabolic phenotyping of humans with protein-altering variants in TM6SF2 using a genome-first approach

Background & Aim

An unbiased genome-first approach can expand the molecular understanding of specific genes in disease-agnostic biobanks for deeper phenotyping. TM6SF2 represents a good candidate for this approach due to its known association with steatotic liver disease (SLD).

Methods

We screened participants with whole-exome sequences in the Penn Medicine Biobank (PMBB, n >40,000) and the UK Biobank (UKB, n >200,000) for protein-altering variants in TM6SF2 and evaluated their association with liver phenotypes and clinical outcomes.

Results

Missense variants in TM6SF2 (E167K, L156P, P216L) were associated with an increased risk of clinically diagnosed and imaging-proven steatosis, independent of the PNPLA3 I48M risk allele and hepatitis B/C (p <0.001). E167K homozygotes had significantly increased risk of SLD (odds ratio [OR] 5.38, p <0.001), steatohepatitis (OR 5.76, p <0.05) and hepatocellular carcinoma (OR 11.22, p <0.0001), while heterozygous carriers of L156P and P216L were also at an increased risk of steatohepatitis. In addition, carriers of E167K are at a 3-fold increased risk of at-risk MASH (OR 2.75, p <0.001). CT-derived liver fat scores were higher in E167K and L156P in an allele-dose manner (p <0.05). This corresponded with the UKB nuclear magnetic resonance-derived lipidomic analyses (n = 105,348), revealing all carriers to exhibit lower total cholesterol, triglycerides and total choline. In silico predictions suggested that these missense variants cause structural disruptions in the EXPERA domain, leading to reduced protein function. This hypothesis was supported by the association of rare loss-of-function variants in TM6SF2 with an increased risk of SLD (OR 4.9, p <0.05), primarily driven by a novel rare stop-gain variant (W35X) with the same directionality.

Conclusion

The functional genetic study of protein-altering variants provides insights on the association between loss of TM6SF2 function and SLD and provides the basis for future mechanistic studies.

Impact and implications

The genome-first approach expands insights into genetic risk factors for steatotic liver disease with TM6SF2 being a focal point due to its known association with plasma lipid traits. Our findings validated the association of two missense variants (E167K and L156P) with increased risk of hepatic steatosis on CT and MRI scans, as well as the risk of clinically diagnosed hepatocellular carcinoma independent of the common PNPLA3 I48M risk variant. Notably, we also identified a predicted deleterious missense variant (P216L) linked to steatotic risk and demonstrated that an aggregated gene burden of rare putative loss-of-function variants was associated with the risk of hepatic steatosis. Combined, this study sets the stage for future mechanistic investigations into the functional consequences of TM6SF2 variants in metabolic dysfunction-associated steatotic liver disease.

Prevalence of Non-Alcoholic Fatty Liver Disease and Its Impact on Fibrosis Risk in Inactive Chronic Hepatitis B Patients: Insights from a Cross-Sectional Study

Background: Chronic hepatitis B (CHB) and non-alcoholic fatty liver disease (NAFLD) are significant causes of chronic liver disease, potentially leading to liver cirrhosis and hepatocellular carcinoma. Moreover, the coexistence of CHB and NAFLD is increasingly common, although the relationship between NAFLD and inactive CHB infection remains poorly understood. Objectives: This study aimed to investigate the prevalence of NAFLD among patients with inactive CHB, identify risk factors for NAFLD, and determine predictors of significant fibrosis in these patients. Methods: This single-center cross-sectional study targeted patients with inactive CHB at Sultan Qaboos University Hospital from January 2010 to November 2021. Results: A total of 425 patients with inactive CHB were identified, of which 53.1% were male and 62.6% were aged 40-60 years. The prevalence of NAFLD was 47.8%. Various independent factors were associated with NAFLD, including type 2 diabetes mellitus, elevated low-density lipoprotein levels, high hemoglobin levels, low platelet counts, and normal alpha-fetoprotein levels. Significant associations were noted between NAFLD and significant fibrosis, with 10.5% of CHB patients with NAFLD exhibiting significant fibrosis compared to 1.4% of those without NAFLD. Other significant parameters included male gender, increased age, high alanine transaminase levels, elevated hemoglobin, and decreased platelet levels. Conclusions: The high prevalence of NAFLD in patients with inactive CHB and its associations with increased fibrosis and cirrhosis risk underscore the need for comprehensive management strategies for these patients.

Machine Learning Identifies Metabolic Dysfunction-Associated Steatotic Liver Disease in Patients With Diabetes Mellitus

CONTEXT

The presence of metabolic dysfunction-associated steatotic liver disease (MASLD) in patients with diabetes mellitus (DM) is associated with a high risk of cardiovascular disease, but is often underdiagnosed.

OBJECTIVE

To develop machine learning (ML) models for risk assessment of MASLD occurrence in patients with DM.

METHODS

Feature selection determined the discriminative parameters, utilized to classify DM patients as those with and without MASLD. The performance of the multiple logistic regression model was quantified by sensitivity, specificity, and percentage of correctly classified patients, and receiver operating characteristic (ROC) curve analysis. Decision curve analysis (DCA) assessed the model's net benefit for alternative treatments.

RESULTS

We studied 2000 patients with DM (mean age 58.85 ± 17.37 years; 48% women). Eight parameters: age, body mass index, type of DM, alanine aminotransferase, aspartate aminotransferase, platelet count, hyperuricaemia, and treatment with metformin were identified as discriminative. The experiments for 1735 patients show that 744/991 (75.08%) and 586/744 (78.76%) patients with/without MASLD were correctly identified (sensitivity/specificity: 0.75/0.79). The area under ROC (AUC) was 0.84 (95% CI, 0.82-0.86), while DCA showed a higher clinical utility of the model, ranging from 30% to 84% threshold probability. Results for 265 test patients confirm the model's generalizability (sensitivity/specificity: 0.80/0.74; AUC: 0.81 [95% CI, 0.76-0.87]), whereas unsupervised clustering identified high-risk patients.

CONCLUSION

A ML approach demonstrated high performance in identifying MASLD in patients with DM. This approach may facilitate better risk stratification and cardiovascular risk prevention strategies for high-risk patients with DM at risk of MASLD.

The role of platelets in non-alcoholic fatty liver disease: From pathophysiology to therapeutics

Platelets are one of the key mediators in thrombosis as well as in the progression of many diseases. An increase in platelet activation and a decrease in platelet count is associated with a plethora of liver diseases. In non-alcoholic fatty liver disease (NAFLD), platelets are highly activated and participate in the disease progression by enhancing the pro-thrombotic and pro-inflammatory state. Some altered platelet parameters such as mean platelet volume, plateletcrits, and platelet distribution width, aspartate transaminase to platelet ratio index, liver stiffness to platelet ratio and red cell distribution width to platelet ratio were found to be associated with NAFLD disease. Further, platelet contributes to the progression of cardiovascular complications in NAFLD is gaining the researcher's attention. An elevated mean platelet volume is known to enhance the risk of stroke, atherosclerosis, thrombosis, and myocardial infarction in NAFLD. Evidence also suggested that modulation in platelet function using aspirin, ticlopidine, and cilostazol help in controlling the NAFLD progression. Future research should focus on antiplatelet therapy as a treatment strategy that can control platelet activation in NAFLD as well as its cardiovascular risk. In the present review, we have detailed the role of platelets in NAFLD and its cardiovascular complications. We further aimed to highlight the growing need for antiplatelet therapy in NAFLD.

The Roles of Glucagon-Like Peptide 1 (GLP-1) Receptor Agonists and Sodium-Glucose Cotransporter 2 (SGLT-2) Inhibitors in Decreasing the Occurrence of Adverse Cardiorenal Events in Patients With Type 2 Diabetes

Diabetes mellitus is a metabolic disorder characterized by increased serum glucose due to errors in insulin production or response. The prevalence of diabetes mellitus has continued to rise globally over the years, with roughly 7079 persons per 100,000 expected to be impacted by 2030. A vast number of patients with diabetes mellitus experience unfavorable side effects such as weight gain, hypoglycemia, and hepatorenal toxicity from the several diabetic medications available. These adverse effects may result in life-threatening consequences with a high likelihood of occurrence; therefore, ongoing efforts continue to develop medications with improved tolerability and better glycemic control. Glucagon-like peptide-1 receptor agonists (GLP-1RA) and sodium-glucose cotransporter 2 inhibitors (SGLT-2i) are examples of new innovative targeted therapies to manage diabetes mellitus and potentially improve cardiorenal conditions. This review article details the specific mechanisms of action, potential side effects, and cardiorenal benefits of GLP-1RA and SGLT-2i therapies to fully understand their roles in combating type 2 diabetes mellitus (T2D).

Efficacy of Lipid Ratios and Platelet Distribution Width for Assessment of Liver Fibrosis in Patients With Non-alcoholic Fatty Liver Disease

Introduction The clinical course of non-alcoholic fatty liver disease (NAFLD) in its long term may follow a benign course or have an adverse outcome leading to hepatocellular carcinoma (HCC) or end-stage liver disease requiring liver transplantation. Such patients represent only a small proportion of all NAFLD cases, making case finding a real challenge. Aims This study was planned to test the efficacy of simple laboratory parameters for their ability to screen advanced cases of NAFLD who need early attention to extricate them from the cumbersome outcome. Material and method The study protocol enrolled 129 diagnosed cases of NAFLD. Patients were categorized as group I with mild/moderate fibrosis (MF) comprising of F0 to F2 and group II with advanced fibrosis (AF) comprising of F3 and F4 based on Fibroscan kPa (kilopascal) score. Results Group I consisted of 96 MF patients, while group II included 33 AF patients. Mean values of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), triglyceride (TG), triglyceride/high-density lipoprotein (TG/HDL) ratio, total cholesterol/high-density lipoprotein (TC/HDL) ratio, and platelet distribution width (PDW) were significantly higher in patients with AF (group II), while platelet count (PC) was significantly lower in group II. The area under the receiver operative characteristic (AUROC) curve was highest for PDW [0.730 (0.644-0.815)] and TG/HDL ratio [0.719 (0.612-0.827)]. TG/HDL ratio at a cut-off of >2.4 had a sensitivity and specificity of 84.85% and 34.38%, respectively, and PDW at a cut-off of >16.40 had a sensitivity and specificity of 84.85% and 54.17%, respectively. Conclusion Decent sensitivity at particular cut-offs for TG/HDL ratio and PDW makes them suitable to be applied for screening advanced cases of NAFLD that require early ministration and medication to block its further progression to its intricate form.