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Recent genome-wide association studies (GWAS) have identified a link between single-nucleotide polymorphisms (SNPs) near the MBOAT7 gene and advanced liver diseases. Specifically, the common MBOAT7 variant (rs641738) associated with reduced MBOAT7 expression is impli-cated in non-alcoholic fatty liver disease (NAFLD), alcohol-associated liver disease (ALD), and liver fibrosis. However, the precise mechanism underlying MBOAT7-driven liver disease progression remains elusive. Previously, we identified MBOAT7-driven acylation of lysophosphatidylinositol lipids as key mechanism suppressing the progression of NAFLD (Gwag et al., 2019). Here, we show that MBOAT7 loss of function promotes ALD via reorganization of lysosomal lipid homeostasis. Circu-lating levels of MBOAT7 metabolic products are significantly reduced in heavy drinkers compared to healthy controls. Hepatocyte-(Mboat7-HSKO), but not myeloid-specific (Mboat7-MSKO), deletion of Mboat7 exacerbates ethanol-induced liver injury. Lipidomic profiling reveals a reorganization of the hepatic lipidome in Mboat7-HSKO mice, characterized by increased endosomal/lysosomal lipids. Ethanol-exposed Mboat7-HSKO mice exhibit dysregulated autophagic flux and lysosomal biogen-esis, associated with impaired transcription factor EB-mediated lysosomal biogenesis and auto-phagosome accumulation. This study provides mechanistic insights into how MBOAT7 influences ALD progression through dysregulation of lysosomal biogenesis and autophagic flux, highlighting hepatocyte-specific MBOAT7 loss as a key driver of ethanol-induced liver injury. [ABSTRACT FROM AUTHOR]

Persons who inject drugs and require surgery for infective endocarditis have 2 potentially lethal diseases. Current postoperative rehabilitation efforts seem ineffective in preventing loss to follow-up, injection drug use relapse (relapse), and death. The purpose of this study was to characterize drug use, psychosocial issues, surgical outcome, and postoperative addiction management, as well as loss to follow-up, relapse, and mortality and their risk factors. From January 2010 to June 2020, 227 persons who inject drugs, age 36 ± 9.9 years, underwent surgery for infective endocarditis at a quaternary hospital having special interest in developing addiction management programs. Postsurgery loss to follow-up, relapse, and death were assessed as competing risks and risk factors identified parametrically and by machine learning. CIs are 68% (±1 SE). Heroin was the most self-reported drug injected (n = 183 [81%]). Psychosocial issues included homelessness (n = 56 [25%]), justice system involvement (n = 150 [66%]), depression (n = 118 [52%]), anxiety (n = 104 [46%]), and post-traumatic stress disorder (n = 33 [15%]). Four (1.8%) died in-hospital. Medication for opioid use disorder prescribed at discharge increased from 0% in 2010 to 100% in 2020. At 1 and 5 years, conditional probabilities of loss to follow-up were 16% (68% CI: 13%-22%) and 59% (68% CI: 44%-65%), relapse 32% (68% CI: 28%-34%) and 79% (68% CI: 74%-83%), and mortality 21% (68% CI: 18%-23%) and 68% (68% CI: 62%-72%). Younger age, heroin use, and lower education level were predictors of relapse. Infective endocarditis surgery can be performed with low mortality in persons who inject drugs, but addiction is far more lethal. Risk of loss to follow-up and relapse require more effective addiction strategies without which this major loss to society will continue. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Patients with acute alcohol‐associated hepatitis (AH) have immune dysfunction. Mitochondrial function is critical for immune cell responses and regulates senescence. Clinical translational studies using complementary bioinformatics‐experimental validation of mitochondrial responses were performed in peripheral blood mononuclear cells (PBMC) from patients with AH, healthy controls (HC), and heavy drinkers without evidence of liver disease (HD). Methods: Feature extraction for differentially expressed genes (DEG) in mitochondrial components and telomere regulatory pathways from single‐cell RNAseq (scRNAseq) and integrated 'pseudobulk' transcriptomics from PBMC from AH and HC (n = 4 each) were performed. After optimising isolation and processing protocols for functional studies in PBMC, mitochondrial oxidative responses to substrates, uncoupler, and inhibitors were quantified in independent discovery (AH n = 12; HD n = 6; HC n = 12) and validation cohorts (AH n = 10; HC n = 7). Intermediary metabolites (gas‐chromatography/mass‐spectrometry) and telomere length (real‐time PCR) were quantified in subsets of subjects (PBMC/plasma AH n = 69/59; HD n = 8/8; HC n = 14/27 for metabolites; HC n = 13; HD n = 8; AH n = 72 for telomere length). Results: Mitochondrial, intermediary metabolite, and senescence‐regulatory genes were differentially expressed in PBMC from AH and HC in a cell type–specific manner at baseline and with lipopolysaccharide (LPS). Fresh PBMC isolated using the cell preparation tube generated optimum mitochondrial responses. Intact cell and maximal respiration were lower (p ≤.05) in AH than HC/HD in the discovery and validation cohorts. In permeabilised PBMC, maximum respiration, complex I and II function were lower in AH than HC. Most tricarboxylic acid (TCA) cycle intermediates in plasma were higher while those in PBMC were lower in patients with AH than those from HC. Lower telomere length, a measure of cellular senescence, was associated with higher mortality in AH. Conclusion: Patients with AH have lower mitochondrial oxidative function, higher plasma TCA cycle intermediates, with telomere shortening in nonsurvivors. [ABSTRACT FROM AUTHOR]