Reduced adipocyte glutaminase activity promotes energy expenditure and metabolic health.

Glutamine and glutamate are interconverted by several enzymes and alterations in this metabolic cycle are linked to cardiometabolic traits. Herein, we show that obesity-associated insulin resistance is characterized by decreased plasma and white adipose tissue glutamine-to-glutamate ratios. We couple these stoichiometric changes to perturbed fat cell glutaminase and glutamine synthase messenger RNA and protein abundance, which together promote glutaminolysis.

Unraveling Adipose Tissue Dysfunction: Molecular Mechanisms, Novel Biomarkers, and Therapeutic Targets for Liver Fat Deposition.

Adipose tissue (AT), once considered a mere fat storage organ, is now recognized as a dynamic and complex entity crucial for regulating human physiology, including metabolic processes, energy balance, and immune responses. It comprises mainly two types: white adipose tissue (WAT) for energy storage and brown adipose tissue (BAT) for thermogenesis, with beige adipocytes demonstrating the plasticity of these cells. WAT, beyond lipid storage, is involved in various metabolic activities, notably lipogenesis and lipolysis, critical for maintaining energy homeostasis.

Isthmin-1 (ISM1), a novel adipokine that reflects abdominal adipose tissue distribution in individuals with obesity.

Background: The assessment of obesity-related health risks has traditionally relied on the Body Mass Index and waist circumference, but their limitations have propelled the need for a more comprehensive approach. The differentiation between visceral (VIS) and subcutaneous (SC) fat provides a finer-grained understanding of these risks, yet practical assessment methods are lacking. We hypothesized that combining the SC-VIS fat ratio with non-invasive biomarkers could create a valuable tool for obesity-related risk assessment.

CRISPR/Cas9-mediated deletion of adipocyte genes associated with NAFLD alters adipocyte lipid handling and reduces steatosis in hepatocytes in vitro.

Obesity is a major risk factor for the development of nonalcoholic fatty liver disease (NAFLD), and the subcutaneous white adipose tissue (scWAT) is the primary lipid storage depot and regulates lipid fluxes to other organs. Our previous work identified genes upregulated in scWAT of patients with NAFLD: , , and . Herein, we knocked down (KD) their expression in human adipose-derived mesenchymal stem cells (hADMSCs) using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology and characterized their phenotype.

Triglyceride-rich lipoproteins and insulin resistance in patients with chronic hepatitis C receiving direct-acting antivirals.

Background & Aims: Hepatitis C virus (HCV) interferes with carbohydrate and lipid metabolism causing cardiovascular disease and insulin resistance (IR). Direct-acting antivirals (DAAs) are highly effective for the eradication of HCV, with positive effects on metabolic health although paradoxically associated with increased total and LDL-cholesterol. The aims of this study were 1) to characterize dyslipidemia (lipoprotein content, number, and size) in naive HCV-infected individuals and 2) to evaluate the longitudinal association of metabolic changes and lipoparticle characteristics after DAA therapy.

Gene Therapy Based on Mesenchymal Stem Cells Derived from Adipose Tissue for the Treatment of Obesity and Its Metabolic Complications.

Obesity is a highly prevalent condition often associated with dysfunctional adipose tissue. Stem cell-based therapies have become a promising tool for therapeutic intervention in the context of regenerative medicine. Among all stem cells, adipose-derived mesenchymal stem cells (ADMSCs) are the most easily obtained, have immunomodulatory properties, show great ex vivo expansion capacity and differentiation to other cell types, and release a wide variety of angiogenic factors and bioactive molecules, such as growth factors and adipokines.

Identification of novel targets in adipose tissue involved in non-alcoholic fatty liver disease progression.

Obesity is a major risk factor for the development of Nonalcoholic fatty liver disease (NAFLD). We hypothesize that a dysfunctional subcutaneous white adipose tissue (scWAT) may lead to an accumulation of ectopic fat in the liver. Our aim was to investigate the molecular mechanisms involved in the causative role of scWAT in NALFD progression.

Amino Acid Profile in Malnourished Patients with Liver Cirrhosis and Its Modification with Oral Nutritional Supplements: Implications on Minimal Hepatic Encephalopathy.

Low plasma levels of branched chain amino acids (BCAA) in liver cirrhosis are associated with hepatic encephalopathy (HE). We aimed to identify a metabolic signature of minimal hepatic encephalopathy (MHE) in malnourished cirrhotic patients and evaluate its modification with oral nutritional supplements (ONS) enriched with ß-Hydroxy-ß-methylbutyrate (HMB), a derivative of the BCAA leucine. Post hoc analysis was conducted on a double-blind placebo-controlled trial of 43 individuals with cirrhosis and malnutrition, who were randomized to receive, for 12 weeks, oral supplementation twice a day with either 220 mL of Ensure Plus Advance (HMB group, = 22) or with 220 mL of Ensure Plus High Protein (HP group, = 21).

Regulation of p27 and Cdk2 Expression in Different Adipose Tissue Depots in Aging and Obesity.

Aging usually comes associated with increased visceral fat accumulation, reaching even an obesity state, and favoring its associated comorbidities. One of the processes involved in aging is cellular senescence, which is highly dependent on the activity of the regulators of the cell cycle. The aim of this study was to analyze the changes in the expression of and in different adipose tissue depots during aging, as well as their regulation by obesity in mice.

Adiponectin overexpression in C2C12 myocytes increases lipid oxidation and myofiber transition.

Metabolic syndrome and obesity have detrimental effects on the metabolic function of the skeletal muscle. Mounting evidence indicates that patients with those conditions may present an increased ratio of glycolytic to oxidative fibers associated with a decrease in oxidative capacity. In this regard, adiponectin, a hormone mainly secreted by adipocytes that regulates glucose and lipid metabolism, has emerged as a myokine that could play an important role in this process.