Oxidised Apolipoprotein Peptidome Characterises Metabolic Dysfunction-Associated Steatotic Liver Disease.

Background: Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) encompasses a spectrum of histological conditions ranging from simple steatosis to fibrosing steatohepatitis, and is a risk factor for cardiovascular diseases (CVD). While oxidised apolipoproteins A and B have been linked to obesity and CVD, the association between other oxidised apolipoproteins and MASLD is yet to be established. To fill this gap, we characterised the circulating serum peptidome of patients with MASLD.

Paracrine role of endothelial IGF-1 receptor in depot-specific adipose tissue adaptation in male mice.

During recent decades, changes in lifestyle have led to widespread nutritional obesity and its related complications. Remodelling adipose tissue as a therapeutic goal for obesity and its complications has attracted much attention and continues to be actively explored. The endothelium lines all blood vessels and is close to all cells, including adipocytes.

Lipid metabolism in MASLD and MASH: From mechanism to the clinic.

Metabolic dysfunction-associated steatotic liver disease/steatohepatitis (MASLD/MASH) is recognised as a metabolic disease characterised by excess intrahepatic lipid accumulation due to lipid overflow and synthesis, alongside impaired oxidation and/or export of these lipids. But where do these lipids come from? The main pathways related to hepatic lipid accumulation are lipogenesis and excess fatty acid transport to the liver (due to increased lipolysis, adipose tissue insulin resistance, as well as excess dietary fatty acid intake, in particular of saturated fatty acids). Not only triglycerides but also other lipids are secreted by the liver and are associated with a worse histological profile in MASH, as shown by lipidomics.

Breaking barriers in obesity research: 3D models of dysfunctional adipose tissue.

Obesity is a global health crisis characterised by excessive accumulation of adipose tissue (AT). Under obesogenic conditions, this metabolically active tissue undergoes fibrosis and inflammation, leading to obesity-linked comorbidities. Modelling AT is essential for understanding its pathophysiology and developing treatments to protect against metabolic complications.

Adipose Tissue Dysfunction Determines Lipotoxicity and Triggers the Metabolic Syndrome: Current Challenges and Clinical Perspectives.

The adipose tissue organ is organised as distinct anatomical depots located all along the body axis, and it is constituted of three different types of adipocytes: white, beige and brown, which are integrated with vascular, immune, neural, and extracellular stroma cells. These distinct adipocytes serve different specialised functions. The main function of white adipocytes is to ensure healthy storage of excess nutrients/energy and its rapid mobilisation to supply the demand of energy imposed by physiological cues in other organs, whereas brown and beige adipocytes are designed for heat production through uncoupling lipid oxidation from energy production.

Systemic analysis of lipid metabolism from individuals to multi-organism systems.

Lipid metabolism is recognised as being central to growth, disease and health. Lipids, therefore, have an important place in current research on globally significant topics such as food security and biodiversity loss. However, answering questions in these important fields of research requires not only identification and measurement of lipids in a wider variety of sample types than ever before, but also hypothesis-driven analysis of the resulting 'big data'.

Author Correction: Limited oxygen in standard cell culture alters metabolism and function of differentiated cells.

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The role of brown adipose tissue in branched-chain amino acid clearance in people.

Brown adipose tissue (BAT) in rodents appears to be an important tissue for the clearance of plasma branched-chain amino acids (BCAAs) contributing to improved metabolic health. However, the role of human BAT in plasma BCAA clearance is poorly understood. Here, we evaluate patients with prostate cancer who underwent positron emission tomography-computed tomography imaging after an injection of F-fluciclovine (L-leucine analog).

SMIM1 absence is associated with reduced energy expenditure and excess weight.

Background: Obesity rates have nearly tripled in the past 50 years, and by 2030 more than 1 billion individuals worldwide are projected to be obese. This creates a significant economic strain due to the associated non-communicable diseases. The root cause is an energy expenditure imbalance, owing to an interplay of lifestyle, environmental, and genetic factors.

An unbiased ranking of murine dietary models based on their proximity to human metabolic dysfunction-associated steatotic liver disease (MASLD).

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, encompasses steatosis and metabolic dysfunction-associated steatohepatitis (MASH), leading to cirrhosis and hepatocellular carcinoma. Preclinical MASLD research is mainly performed in rodents; however, the model that best recapitulates human disease is yet to be defined. We conducted a wide-ranging retrospective review (metabolic phenotype, liver histopathology, transcriptome benchmarked against humans) of murine models (mostly male) and ranked them using an unbiased MASLD 'human proximity score' to define their metabolic relevance and ability to induce MASH-fibrosis.

Maternal obesity increases hypothalamic miR-505-5p expression in mouse offspring leading to altered fatty acid sensing and increased intake of high-fat food.

In utero exposure to maternal obesity programs increased obesity risk. Animal models show that programmed offspring obesity is preceded by hyperphagia, but the mechanisms that mediate these changes are unknown. Using a mouse model of maternal obesity, we observed increased intake of a high-fat diet (HFD) in offspring of obese mothers that precedes the development of obesity.

An adipocentric perspective of pancreatic lipotoxicity in diabetes pathogenesis.

Obesity and diabetes represent two increasing and invalidating public health issues that often coexist. It is acknowledged that fat mass excess predisposes to insulin resistance and type 2 diabetes mellitus (T2D), with the increasing incidence of the two diseases significantly associated. Moreover, emerging evidence suggests that obesity might also accelerate the appearance of type 1 diabetes (T1D), which is now a relatively frequent comorbidity in patients with obesity.

Tissue-specific inflammation and insulin sensitivity in subjects with obesity.

Obesity is associated with low-grade inflammation and insulin resistance (IR). The contribution of adipose tissue (AT) and hepatic inflammation to IR remains unclear. We conducted a study across three cohorts to investigate this relationship.

Limited oxygen in standard cell culture alters metabolism and function of differentiated cells.

The in vitro oxygen microenvironment profoundly affects the capacity of cell cultures to model physiological and pathophysiological states. Cell culture is often considered to be hyperoxic, but pericellular oxygen levels, which are affected by oxygen diffusivity and consumption, are rarely reported. Here, we provide evidence that several cell types in culture actually experience local hypoxia, with important implications for cell metabolism and function.

Conjugating uncoupler compounds with hydrophobic hydrocarbon chains to achieve adipose tissue selective drug accumulation.

One potential approach for treating obesity is to increase energy expenditure in brown and white adipose tissue. Here we aimed to achieve this outcome by targeting mitochondrial uncoupler compounds selectively to adipose tissue, thus avoiding side effects from uncoupling in other tissues. Selective drug accumulation in adipose tissue has been observed with many lipophilic compounds and dyes.

RNAkines are secreted messengers shaping health and disease.

Extracellular noncoding RNAs (ncRNAs) have crucial roles in intercellular communications. The process of ncRNA secretion is highly regulated, with specific ncRNA profiles produced under different physiological and pathological circumstances. These ncRNAs are transported primarily via extracellular vesicles (EVs) from their origin cells to target cells, utilising both endocrine and paracrine pathways.

Cold-activated brown fat-derived extracellular vesicle-miR-378a-3p stimulates hepatic gluconeogenesis in male mice.

During cold exposure, activated brown adipose tissue (BAT) takes up a large amount of circulating glucose to fuel non-shivering thermogenesis and defend against hypothermia. However, little is known about the endocrine function of BAT controlling glucose homoeostasis under this thermoregulatory challenge. Here, we show that in male mice, activated BAT-derived extracellular vesicles (BDEVs) reprogram systemic glucose metabolism by promoting hepatic gluconeogenesis during cold stress.

Lipidome Profiling in Childhood Obesity Compared to Adults: A Pilot Study.

The objective is to assess the circulating lipidome of children with obesity before and after lifestyle intervention and to compare the data to the circulating lipidome of adults with obesity before and after bariatric surgery. Ten pediatric (PE) and thirty adult (AD) patients with obesity were prospectively recruited at a referral single center. The PE cohort received lifestyle recommendations.

Adipose tissue plasticity in pheochromocytoma patients suggests a role of the splicing machinery in human adipose browning.

Adipose tissue from pheochromocytoma patients acquires brown fat features, making it a valuable model for studying the mechanisms that control thermogenic adipose plasticity in humans. Transcriptomic analyses revealed a massive downregulation of splicing machinery components and splicing regulatory factors in browned adipose tissue from patients, with upregulation of a few genes encoding RNA-binding proteins potentially involved in splicing regulation. These changes were also observed in cell culture models of human brown adipocyte differentiation, confirming a potential involvement of splicing in the cell-autonomous control of adipose browning.