Targeting membrane contact sites to mediate lipid dynamics: innovative cancer therapies

Membrane contact sites (MCS) are specialized regions where organelles are closely interconnected through membrane structures, facilitating the transfer and exchange of ions, lipids, and other molecules. This proximity enables a synergistic regulation of cellular homeostasis and functions. The formation and maintenance of these contact sites are governed by specific proteins that bring organelle membranes into close apposition, thereby enabling functional crosstalk between cellular compartments. In eukaryotic cells, lipids are primarily synthesized and metabolized within distinct organelles and must be transported through MCS to ensure proper cellular function. Consequently, MCS act as pivotal platforms for lipid synthesis and trafficking, particularly in cancer cells and immune cells within the tumor microenvironment, where dynamic alterations are critical for maintaining lipid homeostasis. This article provides a comprehensive analysis of how these cells exploit membrane contact sites to modulate lipid synthesis, metabolism, and transport, with a specific focus on how MCS-mediated lipid dynamics influence tumor progression. We also examine the differences in MCS and associated molecules across various cancer types, exploring novel therapeutic strategies targeting MCS-related lipid metabolism for the development of anticancer drugs, while also addressing the challenges involved.

Brown Adipose Tissue undergoes pathological perturbations and shapes C2C12 myoblast homeostasis in the SOD1-G93A mouse model of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by the selective loss of motor neurons. The contribution of peripheral organs remains incompletely understood. We focused our attention on brown adipose tissue (BAT) and its secreted extracellular vesicles (EVs) given their role in regulating systemic energy balance. In this study, we employed a multi-omics approach, including RNA sequencing (GEO identifier GSE273052) and proteomics (ProteomeXchange identifier PXD054147), to investigate the alterations in BAT and its EVs in the SOD1-G93A mouse model of ALS. Our results revealed consistent changes in the proteomic and transcriptomic profiles of BAT from SOD1-G93A mice, highlighting alterations such as mitochondrial dysfunction and impaired differentiation capacity. Specifically, primary brown adipocytes (PBAs) from SOD1-G93A mice exhibited differentiation impairment, respiratory defects, and alterations in mitochondrial dynamics. Furthermore, the BAT-derived EVs from SOD1-G93A mice displayed distinct changes in size distribution and cargo content. In parallel, such EVs negatively impacted the differentiation and homeostasis of C2C12 murine myoblasts, as well as induced atrophy in C2C12-derived myotubes. These findings suggest that BAT undergoes pathological perturbations in ALS mouse model and could impact on skeletal muscle homeostasis through the secretion of dysfunctional EVs.

Mitochondrial DAMPs: Key mediators in neuroinflammation and neurodegenerative disease pathogenesis

Neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS) are increasingly linked to mitochondrial dysfunction and neuroinflammation. Central to this link are mitochondrial damage-associated molecular patterns (mtDAMPs), including mitochondrial DNA, ATP, and reactive oxygen species, released during mitochondrial stress or damage. These mtDAMPs activate inflammatory pathways, such as the NLRP3 inflammasome and cGAS-STING, contributing to the progression of neurodegenerative diseases. This review delves into the mechanisms by which mtDAMPs drive neuroinflammation and discusses potential therapeutic strategies targeting these pathways to mitigate neurodegeneration. Additionally, it explores the cross-talk between mitochondria and the immune system, highlighting the complex interplay that exacerbates neuronal damage. Understanding the role of mtDAMPs could pave the way for novel treatments aimed at modulating neuroinflammation and slowing disease progression, ultimately improving patient outcome.

Missense Mutations in FDNC5 Associated with Morphometric Traits and Meat Quality in Hainan Black Goats

Goats are widely recognized for their adaptability and resource efficiency, making them an excellent choice for sustainable farming. However, the Hainan Black goat (HNBG), a vital breed in southern China's tropical regions, faces significant challenges that threaten its productivity and economic viability. Specifically, young HNBGs exhibit stunted growth and poor muscle development, indicating the breed may have more genetic defects that cause the poor phenotypes. The FNDC5 gene, which encodes the protein irisin, plays a key role in promoting mitochondrial biogenesis and oxidative metabolism by activating critical signaling molecules such as PGC-1α, thereby enhancing muscle endurance and metabolic efficiency. This study aimed to investigate the impact of missense mutations in the FNDC5 gene on growth and meat quality traits in HNBGs. We sequenced a population of HNBGs and identified three SNPs that could lead to amino acid substitutions. Notably, SNP1 (p.119A/V) and SNP2 (p.135R/H) showed strong linkage. Predictions on the structural effects of these mutations indicated that SNP1 (p.119A/V) and SNP3 (p.170W/G) could alter the secondary structure of the FNDC5 protein. Association analyses revealed that SNP1 (p.119A/V) and SNP2 (p.135R/H) were significantly associated with morphometric traits and meat quality. The phenotypic values of SNP1 and SNP2 co-mutants were significantly lower than those of other combined genotypes. Furthermore, gene expression levels of FNDC5 varied notably across individuals with different SNP1 genotypes. These findings suggest that FNDC5-SNP1 (p.119A/V) could serve as a promising genetic marker for selecting HNBGs with improved growth and muscle development, offering a potential pathway for enhancing key economic traits in this breed.

Relaxin-2 Exhibits a Beneficial Role in Energy Metabolism to Alleviate Atrial Fibrillation Susceptibility

Atrial fibrillation (AF) is the most common cardiac arrhythmia, with energy metabolic disorder leading to severe clinical courses. Relaxin-2 (RLX), a peptide hormone, has been identified to activate crucial enzymes involved in cellular energy metabolism. However, whether relaxin-2 can improve the energy metabolism of atrial myocytes to inhibit AF pathogenesis remains unknown. Male New Zealand rabbits were randomly separated into sham, right atrial tachypacing (RAP), and RAP with a human recombinant relaxin-2 treatment (0.5 mg/kg) group for 2 weeks, and programmed intracardiac stimulation was performed to assess AF susceptibility. Ultrahigh-performance liquid chromatography (UHPLC) was performed to explore potential metabolic profiles in rabbit atria. Histology, transmission electron microscopy (TEM), Western blot, qRT-PCR, and Seahorse assays were used to explain the molecular mechanisms. The downregulated relaxin family peptide receptor 1 (RXFP1) protein was found in the atria of AF patients and rabbits, as well as in tachypacing HL-1 cells. RLX protected against RAP-induced AF with decreased atrial fibrosis and electrical remodeling in rabbits. UHPLC revealed that RLX improved fatty acid and glucose metabolism by activating the PPAR signaling pathway in rabbit atria. Mechanistically, RLX enhanced peroxisome proliferator-activated receptor-γ (PPARγ) expression via regulating RXFP1, which restored mitochondrial respiration and ATP production, along with reduced mitochondrial reactive oxygen species in both rabbit atria and HL-1 cells. Moreover, overexpression of PPARγ in tachypacing HL-1 cells prevented mitochondrial damage and alleviated energy metabolic disorder. Besides, we found that upregulated serum relaxin-2 levels with altered metabolites, including 13S-hydroxyoctadecadienoic acid, prostaglandin E2, glyceric acid, and deoxyribose 1-phosphate, were correlated with AF occurrence in patients. Our study reveals that relaxin-2 attenuates atrial energy metabolic remodeling to prevent AF pathogenesis, which could be considered a potential therapeutic approach in the clinic.

A Quantitative Approach to Mapping Mitochondrial Specialization and Plasticity

Mitochondria are a diverse family of organelles that specialize to accomplish complimentary functions 1-3. All mitochondria share general features, but not all mitochondria are created equal 4.Here we develop a quantitative pipeline to define the degree of molecular specialization among different mitochondrial phenotypes - or mitotypes. By distilling hundreds of validated mitochondrial genes/proteins into 149 biologically interpretable MitoPathway scores (MitoCarta 3.0 5) the simple mitotyping pipeline allows investigators to quantify and interpret mitochondrial diversity and plasticity from transcriptomics or proteomics data across a variety of natural and experimental contexts. We show that mouse and human multi-organ mitotypes segregate along two main axes of mitochondrial specialization, contrasting anabolic (liver) and catabolic (brain) tissues. In cultured primary human fibroblasts exhibiting robust time-dependent and treatment-induced metabolic plasticity 6-8, we demonstrate how the mitotype of a given cell type recalibrates i) over time in parallel with hallmarks of aging, and ii) in response to genetic, pharmacological, and metabolic perturbations. Investigators can now use MitotypeExplorer.org and the associated code to visualize, quantify and interpret the multivariate space of mitochondrial biology.

A Case Report of Madelung's Disease in Romania

Background: Madelung's disease is a rare lipid metabolic disorder characterized by diffuse and symmetrical adipose tissue deposits in the subcutaneous fascial spaces, presenting with multiple painless masses throughout the body. The disease is more common in middle-aged adults with a history of chronic alcohol consumption. Case Report: This article reports a case of Madelung's disease from Romania in a 67-year-old man admitted to our department for multiple adipose masses located in the neck and upper back. MRI examination of the head and neck revealed symmetrical and non-encapsulated fat deposition. Surgical intervention was performed to resect the adipose masses. The article also discusses the etiology, clinical manifestations, diagnosis, and surgical treatment of large adipose lesions. Conclusions: This case report provides insights for the diagnosis and treatment of Madelung's syndrome.

Plasma irisin levels in newly diagnosed leprosy patients: a case-control study

Leprosy is a granulomatous disease affecting the skin, mucous membrane, and peripheral nerves. Irisin, a novel protein, has been associated with several inflammatory and metabolic diseases and has been demonstrated in peripheral nerve cells. The objective of this study was to compare the plasma irisin levels of newly diagnosed leprosy patients with those of healthy individuals while also assessing the role of irisin in the pathogenesis of leprosy. This case-control study was conducted between January 2024 and July 2024 and compared 29 newly diagnosed leprosy patients with 29 healthy controls. The participants' demographic information and disease history, such as the duration of the disease and whether any additional family members had leprosy, were documented. The subjects' serum irisin levels were quantified via enzyme-linked immunosorbent assay (ELISA). The serum level of irisin was significantly lower in the patient group than in the control group (p value < 0.001). We found lower Irisin levels in leprosy patients than healthy controls, suggesting potential as role as a biomarker for leprosy. Further investigations, involving a large sample sized assessed both during and after therapy, are necessary to clarify the function and predictive significance of irisin in leprosy.

Study insights in the role of PGC-1α in neurological diseases: mechanisms and therapeutic potential

Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), which is highly expressed in the central nervous system, is known to be involved in the regulation of mitochondrial biosynthesis, metabolic regulation, neuroinflammation, autophagy, and oxidative stress. This knowledge indicates a potential role of PGC-1α in a wide range of functions associated with neurological diseases. There is emerging evidence indicating a protective role of PGC-1α in the pathogenesis of several neurological diseases. As such, a deeper and broader understanding of PGC-1α and its role in neurological diseases is urgently needed. The present review provides a relatively complete overview of the current knowledge on PGC-1α, including its functions in different types of neurons, basic structural characteristics, and its interacting transcription factors. Furthermore, we present the role of PGC-1α in the pathogenesis of various neurological diseases, such as intracerebral hemorrhage, ischemic stroke, Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis, Huntington's disease, and other PolyQ diseases. Importantly, we discuss some compounds or drug-targeting strategies that have been studied to ameliorate the pathology of these neurological diseases and introduce the possible mechanistic pathways. Based on the available studies, we propose that targeting PGC-1α could serve as a promising novel therapeutic strategy for one or more neurological diseases.

Monoclonal anti-CD38 therapy in human myeloma: retrospects and prospects

Monoclonal antibody therapy using CD38 as a target remains central to managing human multiple myeloma (MM). CD38 was selected early on as a target for mAb-mediated therapy for MM, driven by findings from an early Cluster of Differentiation (CD) Workshop. The first CD38-targeting antibody to be approved yielded strong trial results, significantly improving survival rates and earning widespread patient acceptance. However, resistance to the therapy later emerged, complicating treatment management. Despite CD38's still central role in MM therapy, too little attention has been paid to its broader roles-not only as a myeloma marker but also as an enzyme and adhesion molecule in physiology. This review, a collaborative effort between basic scientists and clinical experts, explores some of the lesser-known mechanisms of antibody action and interactions with CD38 at key stages of treatment. The review also highlights the relevance of the MM environment, focusing on the importance of the bone marrow (BM) niche. The goal is to identify new agents whose unique properties may enhance tumor eradication. By gaining a deeper understanding of interactions between therapeutic antibodies, myeloma cells, and the tumor microenvironment (TME), it is hoped that previously unrecognized vulnerabilities within the disease may be revealed, paving the way to more effective treatment strategies.

Evolutionary Insights into Irisin/FNDC5: Roles in Aging and Disease from Drosophila to Mammals

The Irisin/FNDC5 protein family has emerged as a pivotal link between exercise and the prevention of age-associated diseases. Irisin is highly expressed during exercise from skeletal and cardiac muscle cells, playing a critical role in mediating systemic health benefits through its actions on various tissues. However, Irisin levels decline with age, correlating with a heightened incidence of diseases such as muscle weakness, cardiovascular disorders, and neurodegeneration. Notably, the administration of Irisin has shown significant potential in both preventing and treating these conditions. Recently, an Irisin/FNDC5 homolog was identified in an invertebrate Drosophila model, providing valuable insights into its conserved role in exercise physiology. Importantly, Irisin/FNDC5 has been demonstrated to regulate autophagy-a process essential for clearing excessive nutrients, toxic aggregates, and dysfunctional organelles-in both flies and mammals. Dysregulated autophagy is often implicated in age-related diseases, highlighting its relevance to Irisin/FNDC5's functions. These findings deepen our understanding of Irisin/FNDC5's roles and its potential as a therapeutic target for mitigating aging-related health decline. Further studies are needed to elucidate the precise mechanisms by which Irisin regulates autophagy and its broader impact on physiological aging and related diseases.

Near-Native Imaging of Metal Ion-Initiated Cell State Transition

Metal ions are indispensable to life, as they can serve as essential enzyme cofactors to drive fundamental biochemical reactions, yet paradoxically, excess is highly toxic. Higher-order cells have evolved functionally distinct organelles that separate and coordinate sophisticated biochemical processes to maintain cellular homeostasis upon metal ion stimuli. Here, we uncover the remodeling of subcellular architecture and organellar interactome in yeast initiated by several metal ion stimulations, relying on near-native three-dimensional imaging, cryo-soft X-ray tomography. The three-dimensional architecture of intact yeast directly shows that iron or manganese triggers a hormesis-like effect that promotes cell proliferation. This process leads to the reorganization of organelles in the preparation for division, characterized by the polar distribution of mitochondria, an increased number of lipid droplets (LDs), volume shrinkage, and the formation of a hollow structure. Additionally, vesicle-like structures that detach from the vacuole are observed. Oppositely, cadmium or mercury causes stress-associated phenotypes, including mitochondrial fragmentation, LD swelling, and autophagosome formation. Notably, the organellar interactome, encompassing the interactions between mitochondria and LDs and those between the nuclear envelope and LDs, is quantified and exhibits alteration with multifaceted features in response to different metal ions. More importantly, the dynamics of organellar architecture render them more sensitive biomarkers than traditional approaches for assessing the cell state. Strikingly, yeast has a powerful depuration capacity to isolate and transform the overaccumulated cadmium in the vacuole, mitochondria, and cytoplasm as a high-value product, quantum dots. This work presents the possibility of discovering fundamental links between organellar morphological characteristics and the cell state.

Association of Serum Irisin With Severity and Prognosis in Patients With Coronavirus Disease 2019: A Prospective Cohort Study

Background

Irisin is the cleaved form of fibronectin type III domain-containing protein 5 (FNDC5), which can confer antioxidant and anti-inflammatory effects. Several studies have revealed that irisin can alleviate lung injury and affect the pathology of coronavirus disease 2019 (COVID-19). The aim of this study was to assess the relationships of serum irisin with the severity and prognosis of COVID-19.

Methods

A total of 328 COVID-19 patients were recruited. Peripheral blood samples were collected. The level of serum irisin was determined by ELISA. The associations of serum irisin with COVID-19 severity and prognosis were evaluated through linear and logistic regression models on the basis of a prospective cohort study.

Results

Serum irisin levels were lower in severe patients than in mild patients. The level of serum irisin was gradually decreased with the worsening of COVID-19. Spearman correlation analysis revealed that serum irisin concentration was inversely correlated with several clinical characteristics. Moreover, linear and logistic regression analyses revealed that serum irisin concentration was negatively correlated with the severity score. Interestingly, chronic heart and kidney diseases significantly affected the associations between serum irisin and severity scores. The results of the follow-up study suggested that the level of serum irisin upon admission was reduced in patients who died within one month of hospitalization. A lower serum irisin level at admission increased the risk of death within one month.

Conclusion

Serum irisin levels at admission were negatively correlated with disease severity and prognosis, suggesting that irisin is involved in the pathological process of COVID-19. Serum irisin may be used as a biomarker for diagnostic and prognostic assessment of COVID-19.

Fatty Acid Trafficking Between Lipid Droplets and Mitochondria: An Emerging Perspective

The current understanding of lipid droplets (LDs) in cell biology has evolved from being viewed merely as storage compartments. LDs are now recognized as metabolic hubs that act as cytosolic buffers against the detrimental effects of free fatty acids (FAs). Upon activation, FAs traverse various cellular pathways, including oxidation in mitochondria, integration into complex lipids, or storage in triacylglycerols (TGs). Maintaining a balance among these processes is crucial in cellular FA trafficking, and under metabolically challenging circumstances the routes of FA metabolism adapt to meet the current cellular needs. This typically involves an increased demand for anabolic intermediates or energy and the prevention of redox stress. Surprisingly, LDs accumulate under certain conditions such as amino acid starvation. This review explores the biochemical aspects of FA utilization in both physiological contexts and within cancer cells, focusing on the metabolism of TGs, cholesteryl esters (CEs), and mitochondrial FA oxidation. Emphasis is placed on the potential toxicity associated with non-esterified FAs in cytosolic and mitochondrial compartments. Additionally, we discuss mechanisms that lead to increased LD biogenesis due to an inhibited mitochondrial import of FAs.

Single-nucleus transcriptomes reveal the underlying mechanisms of dynamic whitening in thermogenic adipose tissue in goats

BACKGROUND

Thermogenic adipose tissue, both beige and brown, experiences whitening as animals are exposed to warmth and age, but the potential mechanisms are not fully understood. In this study, we employed single-nucleus RNA-seq to construct a cell atlas during whitening progression and identified the characteristics of thermogenic adipocytes.

RESULTS

Our histological studies and bulk transcriptome gene expression analysis confirmed that both perirenal and omental adipose tissues (pAT and oAT) exhibited progressive whitening in goats. Compared to the classic brown adipocytes in mice, goat thermogenic adipocytes were more closely related in gene expression patterns to human beige adipocytes, which was also confirmed by adipocyte type- and lineage-specific marker expression analysis. Furthermore, trajectory analysis revealed beige- and white-like adipocytes deriving from a common origin, coexisting and undergoing the transdifferentiation. In addition, differences in gene expression profiles and cell communication patterns (e.g., FGF and CALCR signaling) between oAT and pAT suggested a lower thermogenic capacity of oAT than that of pAT.

CONCLUSIONS

We constructed a cell atlas of goat pAT and oAT and descripted the characteristics of thermogenic adipocytes during whitening progression. Altogether, our results make a significant contribution to the molecular and cellular mechanisms behind the whitening of thermogenic adipocytes, and providing new insights into obesity prevention in humans and cold adaptation in animals.

A Quantitative Approach to Mapping Mitochondrial Specialization and Plasticity

Mitochondria are a diverse family of organelles that specialize to accomplish complimentary functions1-3. All mitochondria share general features, but not all mitochondria are created equal4. Here we develop a quantitative pipeline to define the degree of molecular specialization among different mitochondrial phenotypes - or mitotypes. By distilling hundreds of validated mitochondrial genes/proteins into 149 biologically interpretable MitoPathway scores (MitoCarta 3.05) the simple mitotyping pipeline allows investigators to quantify and interpret mitochondrial diversity and plasticity from transcriptomics or proteomics data across a variety of natural and experimental contexts. We show that mouse and human multi-organ mitotypes segregate along two main axes of mitochondrial specialization, contrasting anabolic (liver) and catabolic (brain) tissues. In cultured primary human fibroblasts exhibiting robust time-dependent and treatment-induced metabolic plasticity6-8, we demonstrate how the mitotype of a given cell type recalibrates i) over time in parallel with hallmarks of aging, and ii) in response to genetic, pharmacological, and metabolic perturbations. Investigators can now use MitotypeExplorer.org and the associated code to visualize, quantify and interpret the multivariate space of mitochondrial biology.

Gut microbiota-derived short chain fatty acids act as mediators of the gut-liver-brain axis

The gut microbiota plays a crucial role in the communication between the gut, liver, and brain through the production of short chain fatty acids (SCFAs). SCFAs serve as key mediators in the Gut-Liver-Brain Axis, influencing various physiological processes and contributing to overall health. SCFAs are produced by bacterial fermentation of dietary fiber in the gut, and they exert systemic effects by signaling through various pathways. In the Gut-Liver axis, SCFAs regulate liver metabolism through peroxisome proliferator-activated receptor-γ (PPAR-γ), AMP-activated protein kinase (AMPK) and other pathways, promotes fat oxidation, modulate inflammation through mTOR pathway, and impact metabolic health. In the Gut-Brain axis, SCFAs influence brain function, behavior, and may have implications for neurological disorders, in which G-protein coupled receptors (GPCRs) play an essential role, along with other pathways such as hypothalamic-pituitary-adrenal (HPA) pathway. Understanding the mechanisms by which SCFAs mediate communication between the gut, liver, and brain is crucial for elucidating the complex interplay of the Gut-Liver-Brain Axis. This review aims to provide insight into the role of gut microbiota-derived SCFAs as mediators of the Gut-Liver-Brain Axis and their potential therapeutic implications. Further research in this area will be instrumental in developing novel strategies to target the Gut-Liver-Brain Axis for the prevention and treatment of various health conditions.

Naringenin Decreases Retroperitoneal Adiposity and Improves Metabolic Parameters in a Rat Model of Western Diet-Induced Obesity

Background: Obesity is a multifactorial disease with detrimental effects on health and quality of life; unregulated satiety plays a crucial role in food intake and obesity development. Naringenin (NAR) has shown beneficial effects on lipid and carbohydrate metabolism, although its impact on adiposity and satiety remains unclear. This study reports a Western diet (WD)-induced obesity model in rats, wherein 100 mg/kg of NAR was administered as an anti-obesity agent for 8 weeks; oxidative stress, lipid profile, and satiety biomarkers were then studied, as well as in silico interaction between NAR and cholecystokinin (CCK) and ghrelin receptors. Results: NAR supplementation resulted in a significant decrease in retroperitoneal adipose tissue and liver weight, as compared to the untreated WD group (p < 0.05), potentially associated with a decreased feed efficiency. NAR also inhibited the development of dyslipidemia, particularly by reducing serum triglycerides (p < 0.05). NAR supplementation increased CCK serum levels in the basal diet group, an effect that was abolished by the WD (p < 0.05); likewise, no changes were determined on ghrelin (p > 0.05). In silico data shows that NAR is capable of interacting with the CCK and ghrelin receptors, which suggests a potential for it to modulate hunger/satiety signaling by interacting with them. Conclusions: We conclude that NAR has anti-obesogenic effects and may regulate CCK serum levels, although further research is still needed.

Impact of Mesotherapy with Sodium Deoxycholate on Liver: Metabolic- and Sex-Specific Insights in Swiss mice

Sodium deoxycholate (DC) mesotherapy is approved for submental fat reduction but lacks evidence for body contouring safety in other body regions. Thus, we studied the systemic and hepatic metabolic effects of DC mesotherapy (50 µg/twice weekly for 4 weeks) in the inguinal white adipose tissue of female and male Swiss mice on a 20% fructose diet (drinking water) for 12 weeks. DC led to adipose tissue hemorrhage, foam cells, and fibrosis, although no body weight and adiposity loss, similar to humans. In males, glucose and hepatic metabolism, hepatic morphology, and protein expression (farnesoid X receptor and fibroblast growth factor-21) did not change by DC, even under fructose feeding. In females, although DC increased hepatic total cholesterol, most changes when detected were due to fructose (e.g., hepatic weight and lipid deposition). In conclusion, chronic DC mesotherapy proved safe for systemic and hepatic metabolism, and when adverse effects are present, they are sex-specific, impacting mostly females, especially under an unhealthy diet. Overall, care must be taken to extrapolate this data to humans since further studies are required to prove its safety in other body systems.

Berberine-induced browning and energy metabolism: mechanisms and implications

Obesity has become a global pandemic. The approaches researched to prevent it include decreasing energy intake and/or enhancing energy expenditure. Therefore, research on brown adipose tissue is of great importance. Brown adipose tissue is characterized by its high mitochondrial content. Mitochondrial uncoupling protein 1 (UCP1) releases energy as heat instead of chemical energy. Thermogenesis increases energy expenditure. Berberine, a phytochemical widely used in Asian countries, has positive effects on body weight control. While the precise mechanisms behind this effect remain unclear, the adenosine monophosphate-activated protein kinase (AMPK) pathway is known to play a crucial role. Berberine activates AMPK through phosphorylation, significantly impacting brown adipose tissue by enhancing lipolytic activity and increasing the expression of UCP1, peroxisome proliferator-activated receptor γ-co-activator-1α (PGC1α), and PR domain containing 16 (PRDM16). While investigating the mechanism of action of berberine, both the AMPK pathway is being examined in more detail and alternative pathways are being explored. One such pathway is growth differentiation factor 15 (GDF15), known for its appetite-suppressing effect. Berberine's low stability and bioavailability, which are the main obstacles to its clinical use, have been improved through the development of nanotechnological methods. This review examines the potential mechanisms of berberine on browning and summarizes the methods developed to enhance its effect.

Vitamin D Enhancement of Adipose Biology: Implications on Obesity-Associated Cardiometabolic Diseases

Vitamin D is activated into 1α,25(OH)2D through two hydroxylation steps that are primarily catalyzed by 25-hydroxylase in the liver and 1α-hydroxylase in the kidneys. The active form of vitamin D regulates myriads of cellular functions through its nuclear receptor, vitamin D receptor (VDR). Vitamin D metabolizing enzymes and VDR are expressed in adipose tissues and vitamin D regulates multiple aspects of adipose biology including the recruitment and differentiation of adipose stem cells into adipocytes and metabolic, endocrine, and immune properties. Obesity is associated with low vitamin D status, which is thought to be explained by its sequestration in large mass of adipose tissues as well as dysregulated vitamin D metabolism. Low vitamin D status in obesity may negatively impact adipose biology leading to adipose tissue dysfunctions, the major pathological factors for cardiometabolic diseases in obesity. In this review, the current understanding of vitamin D metabolism and its molecular mechanisms of actions, focusing on vitamin D-VDR regulation of adipose biology with their implications on obesity-associated diseases, is discussed. Whether improving vitamin D status leads to reductions in adiposity and risks for cardiometabolic diseases is also discussed.

ATGL regulates renal fibrosis by reprogramming lipid metabolism during the transition from AKI to CKD

Acute kidney injury (AKI) can progress to chronic kidney disease (CKD) and subsequently to renal fibrosis. Poor repair of renal tubular epithelial cells (TECs) after injury is the main cause of renal fibrosis. Studies have shown that restoring damaged fatty acid β-oxidation (FAO) can reduce renal fibrosis. Adipose triglyceride lipase (ATGL) is a key enzyme that regulates lipid hydrolysis. This study, for the first time, demonstrated that ATGL was downregulated in the renal TEC in the AKI-CKD transition mouse model. Moreover, treatment with the ATGL inhibitor atglistatin exacerbated lipid accumulation and downregulated the FAO level and mitochondrial function, while it increased the level of oxidative stress injury and apoptosis, resulting in aggravated renal fibrosis. In contrast, ATGL overexpression suppressed lipid accumulation, improved the FAO level and mitochondrial function, and attenuated oxidative stress and apoptosis, thereby ameliorating fibrosis in vitro and in vivo. In summary, ATGL regulates renal fibrosis by reprogramming lipid metabolism in renal TECs. This study provided new avenues and targets for treating CKD.

A biallelically active embryonic enhancer dictates GNAS imprinting through allele-specific conformations

Genomic imprinting controls parental allele-specific gene expression via epigenetic mechanisms. Abnormal imprinting at the GNAS gene causes multiple phenotypes, including pseudohypoparathyroidism type-1B (PHP1B), a disorder of multihormone resistance. Microdeletions affecting the neighboring STX16 gene ablate an imprinting control region (STX16-ICR) of GNAS and lead to PHP1B upon maternal but not paternal inheritance. Mechanisms behind this imprinted inheritance mode remain unknown. Here, we show that the STX16-ICR forms different chromatin conformations with each GNAS parental allele and enhances two GNAS promoters in human embryonic stem cells. When these cells differentiate toward proximal renal tubule cells, STX16-ICR loses its effect, accompanied by a transition to a somatic cell-specific GNAS imprinting status. The activity of STX16-ICR depends on an OCT4 motif, whose disruption impacts transcript levels differentially on each allele. Therefore, a biallelically active embryonic enhancer dictates GNAS imprinting via different chromatin conformations, underlying the allele-specific pathogenicity of STX16-ICR microdeletions.

hBMSC-EVs alleviate weightlessness-induced skeletal muscle atrophy by suppressing oxidative stress and inflammation

BACKGROUND

Muscle disuse and offloading in microgravity are likely the primary factors mediating spaceflight-induced muscle atrophy, for which there is currently no effective treatment other than exercise. Extracellular vesicles derived from bone marrow mesenchymal stem cells (BMSC-EVs) possess anti-inflammatory and antioxidant properties, offering a potential strategy for combating weightless muscular atrophy.

METHODS

In this study, human BMSCs-EVs (hBMSC-EVs) were isolated using super-centrifugation and characterized. C2C12 myotube nutrition-deprivation and mice tail suspension models were established. Subsequently, the diameter of C2C12 myotubes, Soleus mass, cross-sectional area (CSA) of muscle fibers, and grip strength in mice were assessed to investigate the impact of hBMSC-EVs on muscle atrophy. Immunostaining, transmission electron microscopy observation, and western blot analysis were employed to assess the impact of hBMSC-EVs on muscle fiber types, ROS levels, inflammation, ubiquitin-proteasome system activity, and autophagy lysosome pathway activation in skeletal muscle atrophy.

RESULTS

The active hBMSC-EVs can be internalized by C2C12 myotubes and skeletal muscle. hBMSC-EVs can effectively reduce C2C12 myotube atrophy caused by nutritional deprivation, with a concentration of 10 × 108 particles/mL showing the best effect (P < 0.001). Additionally, hBMSC-EVs can down-regulate the protein levels associated with UPS and oxidative stress. Moreover, intravenous administration of hBMSC-EVs at a concentration of 1 × 1010 particles/mL can effectively reverse the reduction in soleus mass (P < 0.001), CSA (P < 0.01), and grip strength (P < 0.001) in mice caused by weightlessness. They demonstrate the ability to inhibit protein degradation mediated by UPS and autophagy lysosome pathway, along with the suppression of oxidative stress and inflammatory responses. Furthermore, hBMSC-EVs impede the transition of slow muscle fibers to fast muscle fibers via upregulation of Sirt1 and PGC-1α protein levels.

CONCLUSIONS

Our findings indicate that hBMSC-EVs are capable of inhibiting excessive activation of the UPS and autophagy lysosome pathway, suppressing oxidative stress and inflammatory response, reversing muscle fiber type transformation, effectively delaying hindlimb unloading-induced muscle atrophy and enhancing muscle function. Our study has further advanced the understanding of the molecular mechanism underlying muscle atrophy in weightlessness and has demonstrated the protective effect of hBMSC-EVs on muscle atrophy.

Non-canonical lysosomal lipolysis drives mobilization of adipose tissue energy stores with fasting

Physiological adaptations to fasting enable humans to survive for prolonged periods without food and involve molecular pathways that may drive life-prolonging effects of dietary restriction in model organisms. Mobilization of fatty acids and glycerol from adipocyte lipid stores by canonical neutral lipases, including the rate limiting adipose triglyceride lipase (Pnpla2/ATGL), is critical to the adaptive fasting response. Here we discovered an alternative mechanism of lipolysis in adipocytes involving a lysosomal program. We functionally tested lysosomal lipolysis with pharmacological and genetic approaches in mice and in murine and human adipocyte and adipose tissue explant culture, establishing dependency on lysosomal acid lipase (LIPA/LAL) and the microphthalmia/transcription factor E (MiT/TFE) family. Our study establishes a model whereby the canonical pathway is critical for rapid lipolytic responses to adrenergic stimuli operative in the acute stage of fasting, while the alternative lysosomal pathway dominates with prolonged fasting.

Deciphering the Role of CD36 in Gestational Diabetes Mellitus: Linking Fatty Acid Metabolism and Inflammation in Disease Pathogenesis

Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications which exerts detrimental effects on mothers and children. Emerging evidence has pointed to the important role of the fatty acid transporter protein CD36 in the pathogenesis of GDM. As a heavily glycosylated transmembrane protein, CD36 is widely expressed in diverse cell types, including placental trophoblasts, monocytes/macrophages, adipocytes, and pancreatic cells et al. CD36 plays a key role in lipid metabolism and signal transduction in the pathophysiological mechanism of GDM. The modified expression and functionality of CD36 may contribute to inflammation and oxidative stress in maternal tissues, interfere with insulin signaling, and subsequently influence maternal insulin sensitivity and fetal growth, increasing the risk for GDM. This review provides an overview of the current knowledge regarding the expression and function of CD36 in various tissues throughout pregnancy and explores how CD36 dysregulation can activate inflammatory pathways, worsen insulin resistance, and disrupt lipid metabolism, thereby complicating the necessary metabolic adjustments during pregnancy. Furthermore, the review delves into emerging therapeutic approaches targeting CD36 signaling to alleviate the impacts of GDM. Understanding the involvement of CD36 in GDM could yield crucial insights into its mechanisms and potential interventions for enhancing maternal and fetal health outcomes.

Implantation of engineered adipocytes suppresses tumor progression in cancer models

Tumors exhibit an increased ability to obtain and metabolize nutrients. Here, we implant engineered adipocytes that outcompete tumors for nutrients and show that they can substantially reduce cancer progression, a technology termed adipose manipulation transplantation (AMT). Adipocytes engineered to use increased amounts of glucose and fatty acids by upregulating UCP1 were placed alongside cancer cells or xenografts, leading to significant cancer suppression. Transplanting modulated adipose organoids in pancreatic or breast cancer genetic mouse models suppressed their growth and decreased angiogenesis and hypoxia. Co-culturing patient-derived engineered adipocytes with tumor organoids from dissected human breast cancers significantly suppressed cancer progression and proliferation. In addition, cancer growth was impaired by inducing engineered adipose organoids to outcompete tumors using tetracycline or placing them in an integrated cell-scaffold delivery platform and implanting them next to the tumor. Finally, we show that upregulating UPP1 in adipose organoids can outcompete a uridine-dependent pancreatic ductal adenocarcinoma for uridine and suppress its growth, demonstrating the potential customization of AMT.

Cellular signalling of melatonin and its role in metabolic disorders

Melatonin released from the pineal gland plays an important role in maintaining the light/dark cycle. Melatonin exerts its effects on various organs through receptor and nonreceptor pathways. Recently, the role of melatonin in various metabolic disorders has been investigated. This review focuses on the molecular pathways associated with melatonin and its role in metabolic disorders. In humans, melatonin acts through two G protein-coupled receptors (MT1 and MT2). Melatonin modulates insulin release, such as elevated insulin levels in the evening compared to morning hours, exerts cardioprotective effects through the cGMP pathway and nitric oxide production in endothelial cells, and controls oxidative stress and apoptosis in myocardial tissue. Melatonin through MT2 receptors increases lipolysis and thermogenesis, which have a positive effect on weight reduction in obese individuals. Currently, most drugs that target melatonin receptors are primarily used to treat neurological disorders. A detailed investigation to explore the role of melatonin and its signalling pathway in peripheral organs is essential to develop therapeutic molecules for managing metabolic disorders.

The kidney-skeletal muscle-heart axis in chronic kidney disease: implications for myokines

Myokines are signalling moieties released by the skeletal muscle in response to acute and/or chronic exercise, which exert their beneficial or detrimental effects through paracrine and/or autocrine pathways on the skeletal muscle and through endocrine pathways in many other organs (e.g. the heart). Interestingly, alterations in myokines have been described in patients with heart failure (HF) that are associated with adverse structural and functional left ventricular remodelling and poor cardiac outcomes. Recent experimental and clinical studies have shown that the muscle regulation of a number of myokines is altered in chronic kidney disease (CKD) thus representing a new molecular aspect of the pathophysiology of skeletal myopathy present in patients with CKD. Muscle dysregulation of myokines may contribute to a number of disorders in non-dialysis and dialysis patients with CKD, including the high risk of developing HF. This possibility would translate into a range of new diagnostic and therapeutic options. In fact, the measurement of circulating myokines opens their possible usefulness as biomarkers to personalize exercise training and pharmacological therapies for the prevention and treatment of HF in patients with CKD and skeletal myopathy. This review will analyse information on some myokines that target the heart and are altered at the level of skeletal muscle and circulation in patients with CKD.

Irisin regulates oxidative stress and mitochondrial dysfunction through the UCP2-AMPK pathway in prion diseases

Prion diseases are a group of fatal neurodegenerative disorders characterized by the abnormal folding of cellular prion proteins into pathogenic forms. The development of these diseases is intricately linked to oxidative stress and mitochondrial dysfunction. Irisin, an endogenous myokine, has demonstrated considerable neuroprotective potential due to its antioxidative properties. However, the protective effects of irisin against prion diseases have yet to be clarified. Our findings indicate that treatment with exogenous irisin can mitigate the apoptosis induced by PrP106-126. Additionally, irisin significantly reduces oxidative stress and alleviates the mitochondrial dysfunction triggered by PrP106-126. Furthermore, irisin treatment targets uncoupling protein 2 (UCP2) and activates the AMPK-Nrf2 pathway, substantially improving oxidative stress and mitochondrial dysfunction in N2a cells induced by PrP106-126. These results suggest that irisin represents a novel and promising therapeutic approach for treating prion diseases.

Neighborhood Environment, DNA Methylation, and Presence of Crown-Like Structures of the Breast

Importance

Inflammation impacts cancer risk and tumor biological processes, yet studies linking it to social and environmental risk factors are lacking.

Objective

To investigate the association of neighborhood deprivation and air pollution with breast adipose inflammation as well as the association between crown-like structures of the breast (CLS-B) and DNA methylation in Black and White women.

Design, Setting, and Participants

This cross-sectional study analyzed women with and without breast cancer participating in the National Cancer Institute-Maryland Breast Cancer Study, most of whom were recruited between January 1, 1993, and December 1, 2003, from the University of Maryland Medical Center and surrounding hospitals in the Baltimore, Maryland, area. A small subset of the sample was recruited between March 27, 2012, and November 27, 2017. Noncancerous breast tissue was collected from women who underwent reduction mammoplasty or breast cancer surgery. Statistical analyses were conducted between May and August 2024.

Exposures

Two socioenvironmental exposures were examined: air pollution (specifically, fine particulate matter less than 2.5 μm in diameter [PM2.5]) and neighborhood deprivation (measured with Neighborhood Deprivation Index [NDI]). Participant geocodes were linked to 2000 US Census data to calculate PM2.5 concentrations (total mass [μg/m3]) and NDI.

Main Outcomes and Measures

Breast tissues underwent immunohistochemical staining for pan-macrophage marker CD68 to detect 2 outcomes: CLS-B and adipose-associated macrophages. CLS-B and adipose-related macrophages were assessed by pathologists using artificial intelligence-assisted and manual approaches. Covariate-adjusted logistic regression models were used to ascertain associations between PM2.5 and NDI (exposures) and presence or absence of CLS-B (outcome); CD68-positive adipose macrophages were modeled as a dichotomous high or low variable. Covariate-adjusted linear regression was used to identify associations between CLS-B (exposure) and DNA methylation (outcome).

Results

The cohort included 205 participants (127 Black [62.0%], 78 White [38.0%] women; mean [SD] age, 48.7 [13.3] years). Women with vs without CLS-B had higher median (IQR) body mass index (calculated as weight in kilograms divided by height in meters squared; 35.5 [30.5-40.9] vs 31.8 [26.6-36.4]; P = .02). Higher levels of PM2.5 (odds ratio [OR], 2.32; 95% CI, 1.12-4.78; P = .02) and NDI (OR, 1.21; 95% CI, 1.02-1.43; P = .03) were associated with presence of CLS-B overall; findings were still significant among Black women (PM2.5: OR, 2.64 [95% CI, 1.10-6.33], P = .03; NDI: OR, 1.22 [95% CI, 1.01-1.48], P = .04) but were not statistically significant among White women (PM2.5: OR, 1.65 [95% CI, 0.45-5.99], P = .45; NDI: OR, 1.19 [95% CI, 0.83-1.70], P = .35). Higher PM2.5 concentration was associated with increased macrophage infiltration (OR, 2.11; 95% CI, 1.24-3.60; P = .006), with similar outcomes by race. The top 2 significant differentially methylated CpG sites by CLS-B status were SAR1B (β = 0.01; 95% CI, 0.01-0.02; P < .001) and IL2RB (β = -0.04; 95% CI, -0.05 to -0.02; P < .001). Significant interaction was observed between CLS-B status and race for IL2RB methylation levels (β = -0.03; 95% CI, -0.04 to -0.01; P for interaction <.001).

Conclusions and Relevance

This cross-sectional study uncovered an association between neighborhood-level social and environmental risk factors and breast tissue inflammation. The findings help inform efforts to reduce racial and socioeconomic disparities in breast cancer and improve health equity for socially vulnerable populations.

Regulation of adipocyte differentiation and lipid metabolism by novel synthetic chromenes exploring anti-obesity and broader therapeutic potential

Obesity poses a significant global health challenge, necessitating the search for novel therapeutic agents to address this epidemic. Chromenes, known for their diverse bioactivities, hold promise as potential anti-obesity compounds, yet research in this area remains limited. This pioneering study represents the first exploration of synthetic chromenes as potential anti-obesity agents, unveiling the underlying molecular pathways governing adipogenesis and lipolysis. Twenty-nine chromenes were synthesized using green chemistry approaches, resulting in five novel compounds: 1, 2, 3, 4, and 5. Among them, 14 chromenes demonstrated a lack of toxicity to pre-adipocytes (PAs) and mature adipocytes (MAs) of 3T3-L1 cells. The anti-adipogenesis and lipolysis enhancement potential of these non-toxic 14 chromenes were comprehensively evaluated using Oil Red O staining technique, LDH activity measurement, and glycerol release assays. Notably, 4, 5, 21 and 25 exhibited remarkable efficacy in reducing intracellular lipid accumulation without inducing cellular stress or cell death. Molecular analysis revealed significant alterations in the expression of key transcription factors involved in adipogenesis and lipid metabolism, including PPARγ, C/EBPα, ADD-1, Pref-1, IRS-1, GLUT-4, adiponectin, FAS, aP2, ATGL, and HSL. This suggests their potential role in anti-adipogenesis. Additionally, the treatments with 4 and 25 showed potential for enhancing lipolysis, providing further evidence of their anti-obesity properties. This study presents several promising prospects for the development of synthetic chromenes as potential anti-obesity agents, opening new avenues for drug discovery and benefitting individuals worldwide in addressing obesity-related challenges to human health. In addition, predictive in silico modeling was performed on the identified candidate chromenes. This modeling provides prospective anti-HIV activity, pharmacokinetic, metabolism, and permeability data, setting the groundwork for further investigation into these potential new chemical entities.

The Endocannabinoid System: Implications in Gastrointestinal Physiology and Pathology

The endocannabinoid system (ECS), composed of receptors, endocannabinoids, and enzymes that regulate biosynthesis and degradation, plays a fundamental role in the physiology and pathology of the gastrointestinal tract, particularly in the small and large intestine and liver. Specifically, cannabinoid receptor type 1 (CB1R) and cannabinoid receptor type 2 (CB2R), located principally in the nervous system and immune cells, orchestrate processes such as intestinal motility, intestinal and hepatic inflammation, and energy metabolism, respectively. The main endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), influence appetite, body weight regulation, and inflammatory states and thus have implications in obesity, non-alcoholic fatty liver disease (NAFLD) and irritable bowel syndrome (IBS). Recent studies have highlighted the therapeutic potential of targeting the ECS to modulate gastrointestinal and metabolic diseases. In particular, peripheral CB1R antagonists and CB2R agonists have shown efficacy in treating intestinal inflammation, reducing hepatic steatosis, and controlling IBS symptoms. Moreover, the ECS is emerging as a potential target for the treatment of colorectal cancer, acting on cell proliferation and apoptosis. This review highlights the opportunity to exploit the endocannabinoid system in the search for innovative therapeutic strategies, emphasizing the importance of a targeted approach to optimize treatment efficacy and minimize side effects.

Preparation of Morchella esculenta protein and its preventive effect on nonalcoholic fatty liver disease in mice

Morchella esculenta is a valuable edible fungus with multidimensional bioactivities; however, research on M. esculenta protein and its beneficial effects on nonalcoholic fatty liver disease (NAFLD) have been limited. In this study, M. esculenta protein (MEP) with 80.59% protein content was prepared, isolated, and characterized by the complete amino acid composition. The main molecular weight of the protein ranged from 65 to 120 kDa, with 100 kDa being the most dominant band, and it exhibited an alpha helix structure when analyzed by FT-IR and circular dichroism analysis. MEP could regulate body weight, fat accumulation, and alleviate lipid metabolism in adipose tissues in mice with high-fat diet-induced NAFLD. MEP prevented hepatic lipotoxicity, which was reflected in attenuating liver steatosis in vitro and in vivo, thereby regulating the levels of related factors involved in lipid metabolism (e.g., PPARs, HNF-4, SREBP, FASN, ACC-1, and CD36). Furthermore, it inhibited oxidative stress response, which can be attributed to the activation of the MAPK/PGC-1α pathway. Additionally, MEP exhibited probiotic effects, as demonstrated by the altered gut microbiota composition and improved the intestinal barrier integrity. Thus, this study confirmed the preventive effect of MEP against NAFLD by regulating the gut-liver cross-talk, which provided a theoretical basis for the development and utilization of M. esculenta.

The autophagy receptor Ncoa4 controls PPARγ activity and thermogenesis in brown adipose tissue

Adipose tissue dysfunction leads to a variety of deleterious systemic consequences including ectopic lipid deposition and impaired insulin sensitivity. PPARγ is a major regulator of adipocyte differentiation and functionality and is thus a determinant of systemic metabolic health. We recently reported that deletion of adipocyte fatty acid synthase (AdFasnKO) impairs autophagy in association with a striking upregulation of genes controlled by PPARγ, including thermogenic uncoupling protein 1 (Ucp1). In this present study, screening for PPARγ coactivators regulated by autophagy revealed a protein denoted as Nuclear receptor coactivator 4 (Ncoa4), known to mediate ferritinophagy and interact with PPARγ and other nuclear receptors. Indeed, we found Ncoa4 is upregulated in the early phase of adipocyte differentiation and is required for adipogenesis. Ncoa4 is also elevated in FasnKO adipocytes and necessary for full upregulation of Ucp1 expression in vitro , even in response to norepinephrine. Consistent with these findings, adipose-selective knockout of Ncoa4 (AdNcoa4KO mice) impairs Ucp1 expression in brown adipose tissue and cold-induced thermogenesis. Adipose-selective double KO of Fasn plus Ncoa4 (AdFasnNcoa4DKO mice) prevents the upregulation of classic PPARγ target genes normally observed in the white adipose tissue of AdFasnKO mice, but not thermogenic Ucp1 expression. These findings reveal Ncoa4 is a novel determinant of adipocyte PPARγ activity and regulator of white and brown adipocyte biology and suggest that manipulation of autophagy flux modulates PPARγ activity and key adipocyte functions via Ncoa4 actions.

Bone marrow mesenchymal stem cells ameliorate diet-induced obesity by activating thermogenesis and alleviating inflammation in adipose tissue

Obesity and its related metabolic disorders seriously threaten our health and significantly reduce our life expectancy. The aim of the present study was to explore the effects of bone marrow mesenchymal stem cells (BMSCs) on high-fat diet (HFD)-induced obesity mice. The results demonstrated that BMSCs significantly reduced body weight, improved glucose tolerance and insulin sensitivity in obese mice. Further analysis showed that BMSCs could promote brown adipose tissue (BAT) activity and white adipose tissue (WAT) browning by increasing the expression of mitochondrial uncouple protein 1 (UCP1). Additionally, BMSCs markedly increase mitochondrial biogenesis, activate oxidative phosphorylation (OXPHOS) in adipose tissue, further contributing to energy metabolism regulation. Moreover, BMSCs were effective in inhibiting macrophage-related inflammation in adipose tissue, thereby mitigating obesity-associated inflammatory responses. Overall, our results lay the foundation for research on the potential of BMSCs as a promising strategy in alleviating obesity and related metabolic diseases.

Genome-Wide Association Integrating a Transcriptomic Meta-Analysis Suggests That Genes Related to Fat Deposition and Muscle Development Are Closely Associated with Growth in Huaxi Cattle

Growth traits are among the most important economic phenotypes targeted in the genetic improvement of beef cattle. To understand the genetic basis of growth traits in Huaxi cattle, we performed a genome-wide association study (GWAS) on body weight, eye muscle area, and back fat thickness across five developmental stages in a population of 202 Huaxi cattle. Additionally, publicly available RNA-seq data from the longissimus dorsi muscle of both young and adult cattle were analyzed to identify key genes and genetic markers associated with growth in Huaxi cattle. In total, 7.19 million high-quality variant loci (SNPs and INDELs) were identified across all samples. In the GWAS, the three multilocus models (FarmCPU, MLMM, and BLINK) outperformed the conventional single-locus models (CMLM, GLM, and MLM). Consequently, GWAS analysis was conducted using multilocus models, which identified 99 variant loci significantly associated with growth traits and annotated a total of 83 candidate genes (CDGs). Additionally, 23 of the 83 CDGs overlapped with significantly differentially expressed genes identified from public RNA-seq datasets of longissimus dorsi muscle between young and adult cattle. Furthermore, gene functional enrichment (KEGG and GO) analyses revealed that over 30% of the pathways and GO terms were associated with muscle development and fat deposition, crucial factors for beef production. Specifically, key genes identified included MGLL, SGMS1, SNX29 and AKAP6, which are implicated in lipid metabolism, adipogenesis, and muscle growth. In summary, this study provides new insights into the genetic mechanisms underlying growth traits in Huaxi cattle and presents promising markers for future breeding improvements.

Overweight-Related Hypertension in Middle-Aged Men Is Linked to Elevated Leptin, TNF-α, IL-6, Cholesterol, and Reduced Testosterone

BACKGROUND/OBJECTIVES

One of the major causes of hypertension (HT) is the transition of normal weight (NW) status to overweight (OW) status and obesity in a population, which leads to cardiovascular disease (CVD) and other disorders. A variety of factors/variables are involved in the development of HT and OW-related hypertension (OHT). However, we planned to investigate the pathophysiological role of serum leptin (Lep), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), total cholesterol (TC) and serum testosterone (ST) in OHT in middle-aged men.

METHODS

We consulted three groups of middle-aged men (age: 51-60 years)-an HT group (n: 97, high normal weight (HNW), body mass index (BMI): 23-24.9 kg/m2); an OHT group (n: 97, high overweight (HOW), BMI: 28-29.9 kg/m2) and a normal control group (NC, n: 98, HNW)-to investigate the variations in and correlations of Lep, IL-6, TNF-α, ST, TC and other variables.

RESULTS

Significant variations were obtained for the comparisons of TNF-α, Lep, ST and TC for the patient groups. OHT vs. NC showed a significant difference for ST. OHT vs. NC and OHT vs. HT had significant variations for IL-6. Significant changes were obtained for the serum levels of TNF-α, Lep, IL-6, ST and TC among groups. Significant and positive linear associations were obtained for TNF-α, Lep, TC and IL-6. Significant and negative linear associations were found for ST plotted against Lep, TNF-α and IL-6.

CONCLUSIONS

The current report provides pathophysiological evidence of the interactive role of serum Lep, TNF-α, ST, TC and IL-6 in middle-aged men with HT and OHT. We suggest that the changes we noted in the present study would be helpful for further BMI-based studies in various subcategories of NW, OW and obese subjects with/without HT.

Pioglitazone Regulates Chondrocyte Metabolism and Attenuates Osteoarthritis by Activating Peroxisome Proliferator-Activated Receptor Gamma

Osteoarthritis presents a significant clinical challenge due to its high prevalence and the resultant impairment of patients' motor function. Osteoarthritic chondrocytes are characterised by inflammation and metabolic disturbances. Pioglitazone, an agonist of peroxisome proliferator-activated receptor γ (PPAR-γ), has been demonstrated to exert anti-inflammatory effects across various diseases. This study aims to investigate the potential protective effects of Pioglitazone on osteoarthritic chondrocytes. An in vitro chondrocyte inflammation model was established utilising IL-1β. The impact of Pioglitazone on chondrocyte inflammation and extracellular matrix synthesis was evaluated through enzyme-linked immunosorbent assay, immunofluorescence staining and Alcian blue staining. The affinity of Pioglitazone for PPAR-γ was investigated using molecular docking techniques. Alterations in chondrocyte glycolysis and oxidative phosphorylation were examined using the Seahorse XF Analyser, and the influence of Pioglitazone on glucose uptake and the mitochondrial electron transport chain was further analysed. Pioglitazone was gavaged in a mouse OA model established by anterior cruciate ligament transection to evaluate the therapeutic efficacy of Pioglitazone. Our findings indicate that Pioglitazone mitigates chondrocyte inflammation and osteoarthritis in murine models by inhibiting the expression of inflammatory mediators such as TNF-α, IL-6 and PGE2, and by preventing the degradation of aggrecan and collagen II. Furthermore, Pioglitazone significantly upregulated the expression of glucose transporter 1 and stabilised the mitochondrial proton delivery chain in a PPAR-γ-dependent manner, thereby enhancing chondrocyte glucose uptake, glycolysis, and oxidative phosphorylation. These effects were partially reversed by the PPAR-γ antagonist GW9662. Pioglitazone can confer chondroprotective benefits in osteoarthritis by activating PPAR-γ.

Modification of adipogenesis and oxidative stress by quercetin: positive or negative impact on adipose tissue metabolism of obese diabetic Zucker rats?

Reactive oxygen species (ROS) play a key role in the regulation of adipogenesis. The aim of our study was to investigate the effect of quercetin (QCT) supplement on obese adipose tissue metabolism of 30-week-old diabetic Zucker rats (ZDF), not well examined yet. QCT was administered orally at dose of 20 mg/kg body weight/day for 6 weeks. Adipocytes from subcutaneous adipose tissue (ScWAT) were isolated and their size was evaluated by light microscopy. Gene expression of adipogenic markers in subcutaneous and visceral adipose tissue was determined by real-time PCR and expression of proteins involved in lipid and glucose metabolism was determined in ScWAT by immunoblotting. Obese ZDF rats suffered from diabetes, hyperinsulinemia and had higher index HOMA-IR (Homeostatic Model Assessment for Insulin Resistance). Treatment with QCT had no significant impact on these metabolic disorders in genetic model of obesity and type 2 diabetes used in our study. Nevertheless, QCT reduced expression of inflammatory cytokine tumour necrosis factor alpha in ScWAT and also visceral adipose tissue and up-regulated expression of anti-inflammatory adiponectin in ScWAT. A shift in redox equilibrium was detected via inhibition of pro-oxidant genes by QCT. Furthermore, QCT reduced adipocyte size in ScWAT, down-regulated expression of fatty acid synthase and adipogenic markers, and moreover stimulated expression of proteolytic enzymes. These changes likely resulted in reduced fat deposition in ScWAT, which was reflected in the elevated circulated levels of free fatty acids in QCT-treated obese ZDF rats compared with obese untreated controls. This increase could, at least in part, explain why we did not observe an improvement in systemic metabolic health by QCT in our model. In conclusion, our study suggests that preventive treatment with QCT might be more effective than its administration in the stage of fully developed diabetes, and further research in this area is needed.

Serum Irisin as a Predictor for Peripheral Arterial Disease: Insights from a Clinical Study

OBJECTIVE

The purpose of this study was to investigate the correlation between serum irisin concentration and peripheral arterial disease (PAD), and to establish clinical prediction nomograms for PAD occurrence by comparing and analyzing clinical data from patients with PAD and healthy controls.

METHODS

A total of 112 patients with PAD and 90 healthy individuals were recruited for the study. Clinical data from both groups were collected and serum irisin concentration was measured using enzyme-linked immunosorbent assay (ELISA). Correlation analysis was conducted. Risk factors for PAD were identified through univariate and multivariate logistic regression. The clinical prediction nomograms were established and validated.

RESULTS

A total of 202 patients were enrolled in this study, with an average age of 63.98 ± 10.40 years. Of these, 123 were male (60.9%) and 79 were female (39.1%). Hypertension was present in 104 patients (51.5%), diabetes in 59 patients (29.2%), dyslipidemia in 94 patients (46.5%), and 105 patients (52.0%) were smokers. Among them, 112 patients were assigned to the PAD group, which included 78 males (69.6%) and 34 females (30.4%), with an average age of 67.54 ± 10.31 years. In this group, 62 patients (55.4%) had hypertension, 53 (47.3%) had diabetes, 62 (55.4%) had dyslipidemia, and 78 (69.6%) were smokers. The Rutherford classification of these patients showed that 64 (57.1%) were at stage I, 25 (22.3%) at stage II, 16 (14.3%) at stage III, and 7 (6.3%) at stage IV. Serum irisin concentration in patients with PAD showed a significant positive correlation with serum high-density lipoprotein (HDL) (r = 0.255) and a significant negative correlation with Rutherford classification (r = -0.374) and smoking status (r = -0.263). Univariate and multivariate logistic regression analyses identified irisin, age, diabetes, dyslipidemia, smoking, creatinine (CR), and neutrophil/lymphocyte ratio (NLR) as independent risk factors for the development of PAD (P < 0.05). Based on these findings, a clinical prediction nomogram was established. Internal validation of the nomogram demonstrated strong discriminatory ability, with an area under the curve (AUC) of 0.942, indicating the model's excellent performance. Calibration curves and decision curve analyses further confirmed the model's robust calibration and clinical applicability.

CONCLUSIONS

This study concluded that serum irisin concentrations were significantly lower in the PAD group compared to the healthy control group, and that serum irisin concentrations in the PAD group were significantly correlated with serum HDL, Rutherford classification, and smoking status. Additionally, Irisin level, age, diabetes, dyslipidemia, smoking, CR, and NLR were identified as independent risk factors for PAD development. The clinical prediction nomogram based on these factors may aid in accurately predicting the risk of PAD development.

Cannabinoid type-1 receptors in CaMKII neurons drive impulsivity in pathological eating behavior

OBJECTIVES

Overconsumption of palatable food and energy accumulation are evolutionary mechanisms of survival when food is scarce. These innate mechanisms becom detrimental in obesogenic environment promoting obesity and related comorbidities, including mood disorders. This study aims at elucidating the role of the endocannabinoid system in energy accumulation and hedonic feeding.

METHODS

We applied a genetic strategy to reconstitute cannabinoid type-1 receptor (CB1) expression at functional levels specifically in CaMKII+ neurons (CaMKII-CB1-RS) and adipocytes (Ati-CB1-RS), respectively, in a CB1 deficient background.

RESULTS

Rescued CB1 expression in CaMKII+ neurons, but not in adipocytes, promotes feeding behavior, leading to fasting-induced hyperphagia, increased motivation, and impulsivity to palatable food seeking. In a diet-induced obesity model, CB1 re-expression in CaMKII+ neurons, but not in adipocytes, compared to complete CB1 deficiency, was sufficient to largely restore weight gain, food intake without any effect on glucose intolerance associated with high-fat diet consumption. In a model of glucocorticoid-mediated metabolic syndrome, CaMKII-CB1-RS mice showed all metabolic alterations linked to the human metabolic syndrome except of glucose intolerance. In a binge-eating model mimicking human pathological feeding, CaMKII-CB1-RS mice showed increased seeking and compulsive behavior to palatable food, suggesting crucial roles in foraging and an enhanced susceptibility to addictive-like eating behaviors. Importantly, other contingent behaviors, including increased cognitive flexibility and reduced anxiety-like behaviors, but not depressive-like behaviors, were also observed.

CONCLUSIONS

CB1 in CaMKII+ neurons is instrumental in feeding behavior and energy storage under physiological conditions. The exposure to risk factors (hypercaloric diet, glucocorticoid dysregulation) leads to obesity, metabolic syndrome, binge-eating and food addiction.

Compound K promotes thermogenic signature and mitochondrial biogenesis via the UCP1-SIRT3-PGC1α signaling pathway

Compound K (CK), an active ingredient in ginseng, has anti-cancer, anti-inflammatory, and antioxidant properties. However, its effects on thermogenesis and mitochondrial dynamics in white adipose tissue (WAT) adipocytes are not well understood. This study explores CK's impact on thermogenesis and mitochondrial metabolism in cold-exposed mice and mouse stromal vascular fraction (SVF) cells. CK increased the expression of UCP1 and other brown/beige adipocyte markers (Cd137, Cytb, Letm1, Pgc1α, Prdm16, Tbp1, Tbx1, Uqcrc1) and mitochondrial biogenesis/dynamics factors (Cidea, Cox8b, Cycs, Dio2, Drp1, Fis1, Fgf21, Nrf1, Sirt3, Tfam) in 3T3-L1/iWAT SVF cells. CK enhanced mitochondrial respiration, reduced mitochondrial ROS levels, and restored MMP in iWAT SVF cells, leading to the differentiation of WAT into beige adipocytes, and that was also observed in cold-exposed subcutaneous tissue. CK administration to cold-exposed mice reduced fat droplet size and increased the number of mitochondria. Additionally, CK stimulated non-shivering thermogenesis, indicated by the upregulation of thermogenic and mitochondrial division proteins. The browning effect of CK was nullified by SIRT3 knockdown, suggesting that CK induces beige remodeling of WAT by regulating mitochondrial dynamics and SIRT3 expression. These findings suggest CK's potential as a therapeutic agent for obesity and metabolic disorders that promotes the transformation of WAT into a metabolically active beige phenotype.

Kdm2a inhibition in skeletal muscle improves metabolic flexibility in obesity

Skeletal muscle is a critical organ in maintaining homoeostasis against metabolic stress, and histone post-translational modifications are pivotal in those processes. However, the intricate nature of histone methylation in skeletal muscle and its impact on metabolic homoeostasis have yet to be elucidated. Here, we report that mitochondria-rich slow-twitch myofibers are characterized by significantly higher levels of H3K36me2 along with repressed expression of Kdm2a, an enzyme that specifically catalyses H3K36me2 demethylation. Deletion or inhibition of Kdm2a shifts fuel use from glucose under cold challenge to lipids under obese conditions by increasing the proportion of mitochondria-rich slow-twitch myofibers. This protects mice against cold insults and high-fat-diet-induced obesity and insulin resistance. Mechanistically, Kdm2a deficiency leads to a marked increase in H3K36me2 levels, which then promotes the recruitment of Mrg15 to the Esrrg locus to process its precursor messenger RNA splicing, thereby reshaping skeletal muscle metabolic profiles to induce slow-twitch myofiber transition. Collectively, our data support the role of Kdm2a as a viable target against metabolic stress.

Ursolic Acid Restores Redox Homeostasis and Pro-inflammatory Cytokine Production in Denervation-Induced Skeletal Muscle Atrophy

Skeletal muscle (SkM) atrophy results from metabolic disorders causing body and muscle mass loss, affecting morbidity and mortality. Increased oxidative stress, inflammation, and poor prognosis are the leading causes of involuntary weight loss. Ursolic acid (UA), known for its antioxidant and anti-inflammatory properties, can potentially reduce oxidative stress and inflammation in muscles, but its effects on muscle mass regulation are still unknown. Therefore, the present study investigated the medicinal efficacy of UA and its mode of action against the murine model of SkM atrophy over 7 days of UA supplementation. Denervation-induced SkM atrophy significantly impacts overall body weight and the weight of individual muscles (p < 0.05). However, supplementation with UA can effectively counteract these effects by promoting the synthesis of the slow-myosin heavy chain, thereby restoring body weight and myotube diameter. Moreover, UA also plays a crucial role in reducing the production levels of reactive oxygen species (ROS), lipid peroxidation (LPO), and caspase-3-like activity in atrophied muscles. UA also prevents the leakage of creatine kinase (CK) through the upregulation of superoxide dismutase (SOD) and glutathione peroxidase (GPx) expression. Furthermore, the results obtained from qRT-PCR demonstrated a significant decrease in the levels of pro-inflammatory markers, namely IL-1β, IL-6, TNF-α, and TWEAK, up to four-fold after the third day of the UA intervention. UA also upregulated PGC-1α, Bcl2, and p-Aktser473 expression towards the regulation of redox homeostasis.

Detecting white adipose tissue browning in mice with in vivo R2∗ mapping at 9.4T MRI

White adipose tissue (WAT) browning is considered a promising strategy to combat obesity and related metabolic diseases. Currently, fat-water fraction (FWF) has been used as a marker for the loss of lipids associated with WAT browning. However, FWF may not be sensitive to metabolic changes and cannot specifically reflect iron-regulated metabolism during browning. Here, we report a noninvasive preclinical imaging approach based on iron content detected by R2∗ mapping to assess in vivo WAT browning in mice. In this study, we investigated the browning of inguinal white adipose tissue (iWAT) induced by long-term CL-316,243 (CL) drug stimulation in mice. We quantified the changes in R2∗, FWF, uncoupling protein 1 (UCP1) expression, and iron content. The iWAT of all mice was dissected for H&E staining and immunohistochemistry for the absorbance of UCP1 and iron content. In in vivo experiments, a significant increase in R2∗ and a decrease in FWF were observed in iWAT after 7 days of CL administration compared with the saline-treated and the baseline groups. Accordingly, in ex vivo experiments, UCP1 expression and the total iron content in iWAT significantly increased after 7 days of CL stimulation. By pooling all mice data, the UCP1 expression level of iWAT and iron content was found to be highly correlated with R2∗ and inversely correlated with FWF. Taken together, R2∗ may serve as a potential imaging biomarker for assessing WAT browning, which provides a new diagnostic and therapeutic evaluation tool for metabolic diseases.

E3 ligase FBXW7 suppresses brown fat expansion and browning of white fat

Thermogenic fat, including brown and beige fat, dissipates heat via thermogenesis and enhances energy expenditure. Thus, its activation represents a therapeutic strategy to combat obesity. Here, we demonstrate that levels of F-box and WD repeat domain-containing 7 (FBXW7), an E3 ubiquitin protein ligase, negatively correlate with thermogenic fat functionality. FBXW7 overexpression in fat suppresses energy expenditure and thermogenesis, thus aggravates obesity and metabolic dysfunctions in mice. Conversely, FBXW7 depletion in fat leads to brown fat expansion and browning of white fat, and protects mice from diet induced obesity, hepatic steatosis, and hyperlipidemia. Mechanistically, FBXW7 binds to S6K1 and promotes its ubiquitination and proteasomal degradation, which in turn impacts glycolysis and brown preadipocyte proliferation via lactate. Besides, the beneficial metabolic effects of FBXW7 depletion in fat are attenuated by fat-specific knockdown of S6K1 in vivo. In summary, we provide evidence that adipose FBXW7 acts as a major regulator for thermogenic fat biology and energy homeostasis and serves as potential therapeutic target for obesity and metabolic diseases.

Irisin Improves Preeclampsia by Promoting Embryo Implantation and Vascular Remodeling

BACKGROUND

Preeclampsia is a pregnancy-specific disorder with unclear pathogenesis. Irisin, a recently identified exercise-induced factor, significantly influences lipid metabolism and cardiovascular function. Nonetheless, its role in trophoblast development during human placentation and the related intracellular signaling pathways remain poorly understood.

METHODS

We assessed peripheral blood irisin expression in early pregnancy among patients with preeclampsia and its correlation with key clinical indicators. In trophoblast cell lines and mice, we used exogenous irisin and viral knockdown to investigate functional changes. Phosphorylation-specific antibody arrays and dual-luciferase reporter assays were used to explore downstream molecular mechanisms, which were subsequently validated in trophoblast cell lines and relevant gene knockout mice.

RESULTS

In early pregnancy, patients with preeclampsia exhibit decreased peripheral blood irisin levels, occurring earlier than traditional predictive markers, such as PLGF (placental growth factor) and sFlt-1 (soluble fms-like tyrosine kinase-1). Furthermore, irisin concentration is positively correlated with proteinuria and abnormal blood pressure during pregnancy. Exogenous irisin significantly enhanced trophoblast cell migration, invasion, and proliferation while inhibiting apoptosis. It also increased STAT (signal transducers and activators of transcription) 4 phosphorylation and its binding to the GLUT (glucose transporter)-3 promoter, resulting in elevated GLUT-3 expression and glucose uptake in trophoblast cells. In vivo, increased peripheral irisin promoted embryo implantation, vascular remodeling, and enhanced glucose uptake, whereas reduced irisin resulted in a preeclampsia-like phenotype characterized by elevated blood pressure, proteinuria, renal-placental dysfunction, adipose accumulation, and restricted fetal growth.

CONCLUSIONS

Peripheral irisin improves preeclampsia by promoting embryo implantation and vascular remodeling through the activation of the STAT4/GLUT-3 pathway. Reduced peripheral irisin may contribute to preeclampsia-like pathologies. This study supports the advocacy for appropriate exercise during early pregnancy and provides new insights for preeclampsia prevention.