Search Results (43)

Hepatocellular carcinoma (HCC) is the most prevalent subtype of liver cancer with an increasing incidence worldwide. Single nucleotide polymorphisms (SNPs) may influence disease risk and serve as predictive markers. This study aimed to evaluate the association of PNPLA3 (rs738409 and rs2294918), GCKR (rs780094), MBOAT7 (rs641738), NCAN (rs2228603), and TM6SF2 (rs58542926) SNPs with the risk of developing HCC in a Mexican population. A case-control study was conducted in unrelated Mexican individuals. Cases were 173 adults with biopsy-confirmed HCC and 346 were healthy controls. Genotyping was performed using TaqMan allelic discrimination assay. Logistic regression was applied to evaluate associations under codominant, dominant, and recessive inheritance models. p-values were corrected using the Bonferroni test (pC). Haplotype and gene–gene interaction were also analyzed. The GG homozygous of rs738409 and rs2294918 of PNPLA3, TT, and TC genotypes of GCKR, as well as the TT genotype of MBOAT7, were associated with a significant increased risk to HCC under different inheritance models (~Two folds in all cases). The genotypes of NCAN and TM6SF2 did not show differences. The haplotype G-G of rs738409 and rs2294918 of PNPLA3 was associated with an increased risk of HCC [OR (95% CI) = 2.2 (1.7–2.9)]. There was a significant gene–gene interaction between PNPLA3 (rs738409), GCKR (rs780094), and MBOAT7 (rs641738) (Cross-validation consistency (CVC): 10/10; Testing accuracy = 0.6084). This study demonstrates for the first time that PNPLA3 (rs738409 and rs2294918), GCKR (rs780094), and MBOAT7 (rs641738) are associated with an increased risk of developing HCC from multiple etiologies in Mexican patients. Full article

Previous large-scale genetic studies identified single-nucleotide polymorphisms (SNPs) of the membrane bound O-acyltransferase domain containing 7 (MBOAT7) and patatin-like phospholipase domain containing 3 (PNPLA3) genes as risk factors for metabolic dysfunction-associated steatotic liver disease (MASLD). However, this has not yet been investigated in Brazilian patients. In this study, we evaluated the association between the PNPLA3 variant rs738409 and MBOAT7 variant rs641738 and the risk of hepatic fibrosis or liver cirrhosis in MASLD etiology. In parallel, we also aimed to evaluate a protective SNP of the mitochondrial amidoxime-reducing component 1 (MTARC1) gene. We also evaluated TM6SF2 rs58542926, GCKR rs1260326 and rs780094, and HSD17B13 rs72613567 and they were not associated with liver fibrosis. The study was conducted at the Department of Gastroenterology and Nutrology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), and included 113 patients with liver fibrosis (F0–F1), 99 patients with significant liver fibrosis (F2–F4), and 90 controls. SNPs were genotyped by quantitative PCR, using TaqMan allelic discrimination assays. Overall, the PNPLA3 GG genotype was more frequent in F2–F4 (23%) and F0–F1 (22%) patients than in controls (9%; p = 0.02). The MBOAT7 TT genotype was significantly associated with fibrosis, with a prevalence of 23% in F2–F4 patients versus 10% in F0–F1 and 11% in controls (p = 0.01). This association was confirmed by regression analysis (OR = 5.01 95% CI: 1.86–13.49; p = 1.41 × 10⁻³). The protective MTARC1 AA genotypes were more frequent in controls (52%) when compared to patients with fibrosis (5% p = 2.76 × 10⁻²⁰). Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are spreading worldwide as the most critical causes of cirrhosis and hepatocellular carcinoma (HCC). Thus, improving the screening and managing strategies for patients with MASLD or MASH is necessary. A traditional non-systemic review provided this narrative. Genetic variations associated with the development of MASLD and MASH, such as PNPLA3, TM6SF2, GCKR, MBOAT7, MERTK, and HSD17B13, were initially reviewed. PNPLA3 genetic variants appeared to be strongly associated with the increased pathogenesis of MASLD, MASH, cirrhosis, and HCC. We also reviewed the useful polygenic risk score (PRS) for the development of MASLD, MASH, their related cirrhosis, and the occurrence of HCC. PRSs appeared to be better predictors of MASLD, MASH, the development of cirrhosis, and the occurrence of HCC in patients with MASLD or MASH than any single-nucleotide polymorphisms. RNA interference and antisense nucleotides against the genetic variations of PNPLA3 and HSD17B13 are also being developed. Multidisciplinary collaboration and cooperation involving hepatologists, geneticists, pharmacologists, and pathologists should resolve complicated problems in MASLD and MASH. This narrative review highlights the importance of the genetic susceptibility and PRS as predictive markers and personalized medicine for patients with MASLD or MASH in the future. Full article

Genetics and mitochondrial (mt) dysfunction contribute to metabolic dysfunction-associated steatotic liver disease (MASLD). Recently, we demonstrated that the co-presence of PNPLA3, TM6SF2 and MBOAT7 polymorphisms predisposes to disease progression in MASLD patients and that their deletion triggers mt maladaptation in vitro. Here, we deepened the impact of the silencing of these genes on mt dynamism and respiration by reintroducing TM6SF2 and/or MBOAT7 wild-type proteins in deleted cells through lentiviral infection. Since hepatic mt bioenergetics is impaired in MASLD, in the attempt to identify a non-invasive signature, we then compared the enzymatic mt activity of seahorses, which was assessed in liver biopsies and peripheral blood mononuclear cells (PBMCs) of biopsy-proven MASLD patients (n = 44; Discovery cohort) stratified according to the number of the three at-risk variants (3NRV). Concerning the in vitro results, the rescue of MBOAT7 and/or TM6SF2 wild-type proteins resulted in the assembly of spaghetti-shaped mitochondria with improved oxidative phosphorylation (OXPHOS) capacity. In the Discovery cohort, the hepatic bioenergetic profile fully reflected that in PBMCs and was impaired especially in 3NRV carriers. A lowered serum respiration rate was confirmed in noninvasively assessed MASLD (n = 45; Fibroscan-MASLD cohort), while it did not change in unrelated liver disease patients (n = 45). In summary, we firstly demonstrated that mt circulating respirometry reflects that in liver and is specific in defining genetic MASLD. Full article

Ghrelin is a 28 amino acid peptide hormone that impacts a wide range of biological processes, including appetite regulation, glucose metabolism, growth hormone regulation, and cognitive function. To bind and activate its cognate receptor, ghrelin must be acylated on a serine residue in a post-translational modification performed by ghrelin O-acyltransferase (GOAT). GOAT is a membrane-bound O-acyltransferase (MBOAT) responsible for the catalysis of the addition of an octanoyl fatty acid to the third serine of desacyl ghrelin. Beyond its canonical role for ghrelin maturation in endocrine cells within the stomach, GOAT was recently reported to be overexpressed in prostate cancer (PCa) cells and detected at increased levels in the serum and urine of PCa patients. This suggests GOAT can serve as a potential route for the detection and therapeutic targeting of PCa and other diseases that exhibit GOAT overexpression. Building upon a ghrelin mimetic peptide with nanomolar affinity for GOAT, we developed an antibody-conjugate-inspired system for customizable ligand-conjugate (LC) synthesis allowing for the attachment of a wide range of cargoes. The developed synthetic scheme allows for the easy synthesis of the desired LCs and demonstrates that our ligand system tolerates an extensive palette of cargoes while maintaining nanomolar affinity against GOAT. Full article

Background/Objectives: Whether an increased genetic risk of steatotic liver disease (SLD) can be offset by maintaining a healthy weight remains unknown. We aimed to clarify the associations among the body mass index (BMI) and its change patterns with SLD and assess whether genetic susceptibility can modify these associations in Chinese people. Methods: A total of 10,091 and 6124 participants from the Health Omics Preventive Examination (HOPE) Program were enrolled in cross-sectional and follow-up analyses, respectively. BMI change patterns were defined according to the BMI at baseline and the last follow-up visit. Genetic risk was estimated using the polygenic risk score (PRS) derived from variants in PNPLA3, TM6SF2, MBOAT7, and GCKR. Data were analyzed using logistic regression models and Cox proportional-hazards models. Results: The analyses of the BMI and genetic risk simultaneously showed a dose–response association with the risk of SLD (p-trend < 0.001). Significant interactions between BMI and PRS were found for alanine aminotransferase (ALT) elevation (p = 0.007) and aspartate aminotransferase (AST) elevation (p < 0.001). Weight loss led to a 71%, 60%, and 67% lower risk of SLD, ALT elevation, and AST elevation, compared with stable overweight/obesity. A significant interaction between the genetic risk and BMI change patterns in ALT elevation was observed (p = 0.008). The absolute risk reductions associated with weight loss were greater for participants at a high genetic risk (26.60, 12.29, and 9.31 per 100 person years for SLD, ALT elevation, and AST elevation, respectively). Conclusions: Maintaining a healthy weight reduces the liver injury risk among all individuals, and the risk reduction is greater among the subset with a high genetic risk of SLD. Full article

Cognitive impairment (CI) causes severe impairment of brain function and quality of life of patients, which brings a great burden to society. Cerebral hypoxia is an important factor in the pathogenesis of CI. Hyperbaric oxygen (HBO) therapy may mitigate hypoxia-induced CI, but its efficacy and mechanisms are not fully understood. In this study, a mice model of CI induced by hypoxia environment was established, then behavioral tests, pathological examination, metabolomic and lipidomic analyses, and molecular biology were used to assess the impact of HBO on hypoxia-induced CI. HBO was found to alleviate CI and pathological damage of hypoxia mice. Metabolomic, lipidomic, and molecular biology analyses showed that HBO increased the levels of oleic acid (OA) and membrane-bound O-acyltransferase 2 (MBOAT2), thereby altering the composition of membrane phospholipids (PLs) and reducing hypoxia-induced neuronal ferroptosis (FPT) to interfere with cognitive function in mice. In vitro experiments confirmed that OA and MBOAT2 led to membrane PL remodeling in a mutually dependent manner, affecting cell resistance to hypoxia-FPT. The results emphasized the combined effect value of OA and MBOAT2 in HBO for hypoxia-induced CI, and provided a novel perspective for the treatment of CI by HBO. Full article

Metabolic and bariatric surgery (MBS) effectively treats obesity and related comorbidities, though individual responses vary. This systematic review examines how genetic variants influence MBS outcomes in morbidly obese patients. A comprehensive search in PubMed, Embase, Medline, and the Cochrane Library identified 1572 studies, with 52 meeting the inclusion criteria. Two reviewers independently filtered and selected studies, including relevant cross-references. Research focused on polymorphisms in genes such as UCP2, UCP3, 5-HT2C, MC4R, FKBP5, FTO, CAT haplotypes, LYPAL-1, PTEN, FABP-2, CNR1, LEP656, LEP223, GLP-1R, APOA-1, APOE, ADIPOQ, IL-6, PGC1a, TM6SF2, MBOAT7, PNPLA3, TCF7L2, ESR1, GHSR, GHRL, CD40L, DIO2, ACSL5, CG, TAS2R38, CD36, OBPIIa, NPY, BDNF, CLOCK, and CAMKK2. Most studies explored associations with post-surgery weight loss, while some examined metabolic, cardiovascular, taste, and eating behavior effects as well. Understanding the role of genetic factors in weight loss and metabolic outcomes post-MBS can help tailor personalized treatment plans for improved efficacy and long-term success. Further research with larger sample sizes and extended follow-up is needed to clarify the effects of many genetic variants on MBS outcomes in morbidly obese patients. Full article

Cardiometabolic disease (CMD), which encompasses metabolic-associated fatty liver disease (MAFLD), chronic kidney disease (CKD) and cardiovascular disease (CVD), has been increasing considerably in the past 50 years. CMD is a complex disease that can be influenced by genetics and environmental factors such as diet. With the increased reliance on processed foods containing saturated fats, fructose and cholesterol, a mechanistic understanding of how these molecules cause metabolic disease is required. A major pathway by which excessive nutrients contribute to CMD is through oxidative stress. In this review, we discuss how oxidative stress can drive CMD and the role of aberrant nutrient metabolism and genetic risk factors and how they potentially interact to promote progression of MAFLD, CVD and CKD. This review will focus on genetic mutations that are known to alter nutrient metabolism. We discuss the major genetic risk factors for MAFLD, which include Patatin-like phospholipase domain-containing protein 3 (PNPLA3), Membrane Bound O-Acyltransferase Domain Containing 7 (MBOAT7) and Transmembrane 6 Superfamily Member 2 (TM6SF2). In addition, mutations that prevent nutrient uptake cause hypercholesterolemia that contributes to CVD. We also discuss the mechanisms by which MAFLD, CKD and CVD are mutually associated with one another. In addition, some of the genetic risk factors which are associated with MAFLD and CVD are also associated with CKD, while some genetic risk factors seem to dissociate one disease from the other. Through a better understanding of the causative effect of genetic mutations in CMD and how aberrant nutrient metabolism intersects with our genetics, novel therapies and precision approaches can be developed for treating CMD. Full article

Revascularization of coronary chronic total occlusion (CTO) still remains controversial. The factors that impact collateral circulation and myocardial perfusion are of interest. Circular RNA (circRNA) has been shown to regulate the process of angiogenesis. However, the effects of circ-membrane-bound O-acyltransferase domain containing 2 (circ-MBOAT2) on angiogenesis in patients with CTO were unclear. In this study, we evaluated circulating circRNAs and miRNAs in patients with CTO and stable coronary artery disease using high-throughput sequencing. Another cohort of patients were selected to verify the expressions of circ-MBOAT2 and miR-495. The role and mechanism of circ-MBOAT2 in the process of angiogenesis were explored through in vitro and vivo studies. Finally, we came back to a clinical perspective and investigated whether circ-MBOAT2 and miR-495 were associated with the improvement of myocardial perfusion evaluated by single-photon emission computed tomography (SPECT). We found that the expression of circ-MBOAT2 was significantly up-regulated while miR-495 was significantly down-regulated in patients with CTO. The expression of circ-MBOAT2 was negatively correlated with miR-495 in patients with CTO. In an in vitro study, we found that circ-MBOAT2 promoted tube formation and cell migration via the miR-495/NOTCH1 axis in endothelial cells. In an in vivo study, we showed that the inhibition of miR-495 caused the increase in collateral formation in mice after hindlimb ischemia. In a human study, we showed the expressions of circ-MBOAT2 and miR-495 were associated with myocardial perfusion improvement after revascularization of CTO. In conclusion, circ-MBOAT2 regulates angiogenesis via the miR-495/NOTCH1 axis and associates with myocardial perfusion in patients with CTO. Our findings suggest that circ-MBOAT2 and miR-495 may be potential therapeutic targets and prognostic factors for patients with CTO. Full article

Non-alcoholic fatty liver disease (NAFLD) is a common and prevalent disorder affecting 25 percent of the adults in the United States and 32 percent of adults globally. It is one of the common causes of chronic liver disease characterized by steatosis, which can lead to inflammation, fibrosis, and cirrhosis. NAFLD is strongly associated with obesity and insulin resistance. Multiple genetic variants have been consistently found to be associated with NAFLD; one of them is found in the TMC4-MBOAT7 loci. One variant (rs641738 C>T) within MBOAT7 encoding lysophosphatidyl inositol acyltransferase increases the risk for NAFLD development and triggers hepatic inflammation by regulating arachidonic acid levels. This review provides an overview of the MBOAT7 gene, pathogenesis of NAFLD, understanding the regulation of MBOAT7 and mechanistic link between MBOAT7 and NAFLD. It further summarizes pathophysiologically relevant in vivo and in vitro studies on MBOAT7 and challenges in treating complex NAFLD with recent progress made in the treatment of NAFLD. As such, this review provides useful information on MBOAT7 and NAFLD interrelation, which has the potential of deciphering novel therapeutic targets rather than well-known genetic variants such as PNPLA3 and TM6SF2. Full article

Non-alcoholic fatty liver disease (NAFLD) describes a steatotic (or fatty) liver occurring as a consequence of a combination of metabolic, environmental, and genetic factors, in the absence of significant alcohol consumption and other liver diseases. NAFLD is a spectrum of conditions. Steatosis in the absence of inflammation is relatively benign, but the disease can progress into more severe forms like non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. NAFLD onset and progression are complex, as it is affected by many risk factors. The interaction between genetic predisposition and other factors partially explains the large variability of NAFLD phenotype and natural history. Numerous genes and variants have been identified through large-scale genome-wide association studies (GWAS) that are associated with NAFLD and one or more subtypes of the disease. Among them, the largest effect size and most consistent association have been patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2), and membrane-bound O-acyltransferase domain containing 7 (MBOAT7) genes. Extensive in vitro and in vivo studies have been conducted on these variants to validate these associations. The focus of this review is to highlight the genetics underpinning the molecular mechanisms driving the onset and progression of NAFLD and how they could potentially be used to improve genetic-based diagnostic testing of the disease and develop personalized, targeted therapeutics. Full article

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive fat accumulation in the livers of patients without a history of alcohol abuse. It is classified as either simple steatosis (nonalcoholic fatty liver) or nonalcoholic steatohepatitis (NASH), which can progress to liver cirrhosis and hepatocellular carcinoma (HCC). Recently, it was suggested that the terms “metabolic dysfunction-associated steatotic liver disease (MASLD)” and “metabolic dysfunction-associated steatohepatitis (MASH)” should replace the terms “nonalcoholic fatty liver disease (NAFLD)” and “nonalcoholic steatohepatitis (NASH)”, respectively, with small changes in the definitions. MASLD, a hepatic manifestation of metabolic syndrome, is rapidly increasing in incidence globally, and is becoming an increasingly important cause of HCC. Steatohepatitic HCC, a histological variant of HCC, is characterized by its morphological features resembling non-neoplastic steatohepatitis and is closely associated with underlying steatohepatitis and metabolic syndrome. Variations in genes including patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily 2 (TM6SF2), and membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7) are associated with the natural history of MASLD, including HCC development. The mechanisms of HCC development in MASLD have not been fully elucidated; however, various factors, including lipotoxicity, inflammation, reactive oxygen species, insulin resistance, and alterations in the gut bacterial flora, are important in the pathogenesis of MASLD-associated HCC. Obesity and MASLD are also recognized as risk factors for hepatocellular adenomas, and recent meta-analyses have shown an association between MASLD and intrahepatic cholangiocarcinoma. In this review, we outline the pathology and pathogenesis of MASLD-associated liver tumors. Full article

Metabolic-dysfunction-associated steatotic liver disease (MASLD), which affects 30 million people in the US and is anticipated to reach over 100 million by 2030, places a significant financial strain on the healthcare system. There is presently no FDA-approved treatment for MASLD despite its public health significance and financial burden. Understanding the connection between point mutations, liver enzymes, and MASLD is important for comprehending drug toxicity in healthy or diseased individuals. Multiple genetic variations have been linked to MASLD susceptibility through genome-wide association studies (GWAS), either increasing MASLD risk or protecting against it, such as PNPLA3 rs738409, MBOAT7 rs641738, GCKR rs780094, HSD17B13 rs72613567, and MTARC1 rs2642438. As the impact of genetic variants on the levels of drug-metabolizing cytochrome P450 (CYP) enzymes in human hepatocytes has not been thoroughly investigated, this study aims to describe the analysis of metabolic functions for selected phase I and phase II liver enzymes in human hepatocytes. For this purpose, fresh isolated primary hepatocytes were obtained from healthy liver donors (n = 126), and liquid chromatography–mass spectrometry (LC–MS) was performed. For the cohorts, participants were classified into minor homozygotes and nonminor homozygotes (major homozygotes + heterozygotes) for five gene polymorphisms. For phase I liver enzymes, we found a significant difference in the activity of CYP1A2 in human hepatocytes carrying MBOAT7 (p = 0.011) and of CYP2C8 in human hepatocytes carrying PNPLA3 (p = 0.004). It was also observed that the activity of CYP2C9 was significantly lower in human hepatocytes carrying HSD17B13 (p = 0.001) minor homozygous compared to nonminor homozygous. No significant difference in activity of CYP2E1, CYP2C8, CYP2D6, CYP2E1, CYP3A4, ECOD, FMO, MAO, AO, and CES2 and in any of the phase II liver enzymes between human hepatocytes carrying genetic variants for PNPLA3 rs738409, MBOAT7 rs641738, GCKR rs780094, HSD17B13 rs72613567, and MTARC1 rs2642438 were observed. These findings offer a preliminary assessment of the influence of genetic variations on drug-metabolizing cytochrome P450 (CYP) enzymes in healthy human hepatocytes, which may be useful for future drug discovery investigations. Full article

The membrane-bound O-acyltransferase domain-containing 7 (MBOAT7) protein is an acyltransferase catalyzing arachidonic acid incorporation into lysophosphatidylinositol. Patients with rare, biallelic loss-of-function variants of the MBOAT7 gene display intellectual disability with neurodevelopmental defects. The rs641738 inherited variant associated with reduced hepatic MBOAT7 expression has been linked to steatotic liver disease susceptibility. However, the impact of biallelic loss-of-function MBOAT7 variants on liver disease is not known. We report on a 2-year-old girl with MBOAT7-related intellectual disability and steatotic liver disease, confirming that MBOAT7 loss-of-function predisposes to liver disease. Full article