Adiponectin, Leptin, and Fatty Acids in the Maintenance of Metabolic Homeostasis through Adipose Tissue Crosstalk

One-year metreleptin in Colombian sisters with congenital leptin deficiency

We discovered two adult sisters in Colombia, lineally consanguineous, with severe obesity and undetectable serum leptin levels despite markedly elevated body fat. Their clinical profile included childhood-onset extreme weight gain, intense hunger, hyperphagia, hypogonadotropic hypogonadism, and family history of obesity. Direct sequencing of the LEP gene revealed a novel homozygous missense mutation in exon 3 (c.350G>T [p.C117F]). The presence of this mutation, undetectable leptin, and severe obesity confirmed a diagnosis of monogenic leptin deficiency. Here we describe the clinical outcomes of a 12-month treatment with recombinant human leptin (metreleptin). Metabolic and endocrine assessments were conducted before and after therapy. Metreleptin therapy significantly reduced BMI: from 59 to 38 kg/m2 (OBX1, age 27) and 60 to 48 kg/m2 (OBX2, age 24). Total body fat mass decreased, serum lipids normalized, and insulin sensitivity improved. Hypogonadotropic hypogonadism reversed, and menstruation resumed. Thus, metreleptin reversed the major metabolic and endocrine abnormalities associated with leptin deficiency in these sisters. Limitations include the small sample size, absence of a control group, and lack of anti-metreleptin antibody measurements. Nevertheless, our findings support that leptin replacement with metreleptin is currently the only effective hormonal treatment for this monogenic form of human obesity.

Molecular dissection of the role of ACE2 in glucose homeostasis

Angiotensin-converting enzyme 2 (ACE2) was discovered 25 years ago as a negative regulator of the renin-angiotensin system, opposing the effects of angiotensin II. Beyond its well-demonstrated roles in cardiovascular regulation and COVID-19 pathology, ACE2 is involved in a plethora of physiopathological processes. In this review, we summarize the latest discoveries on the role of ACE2 in glucose homeostasis and regulation of metabolism. In the endocrine pancreas, ACE2 is expressed at low levels in β-cells, but loss of its expression inhibits glucose-stimulated insulin secretion and impairs glucose tolerance. Conversely, overexpression of ACE2 improved glycemia, suggesting that recombinant ACE2 might be a future therapy for diabetes. In the skeletal muscle of ACE2-deficient mice a progressive triglyceride accumulation was observed, whereas in diabetic kidney the initial increase in ACE2 is followed by a chronic reduction of expression in kidney tubules and impairment of glucose metabolism. At the intestinal level dysregulation of the enzyme alters the amino acid absorption and intestinal microbiome, whereas at the hepatic level ACE2 protects against diabetic fatty liver disease. Not least, ACE2 is upregulated in adipocytes in response to nutritional stimuli, and administration of recombinant ACE2 decreased body weight and increased thermogenesis. In addition to tissue-specific regulation of ACE2 function, the enzyme undergoes complex cellular posttranslational modifications that are changed during diabetes evolution, with at least proteolytic cleavage and ubiquitination leading to modifications in ACE2 activity. Detailed characterization of ACE2 in a cellular and tissue-specific manner holds promise for improving therapeutic outcomes in diabetes and metabolic disorders.

Changes in lipid metabolism in the visceral rather than the subcutaneous adipose tissue depot attenuate metabolic disturbances in obesity-resistant mice fed a high-fat diet

Obesity is characterized by an enlargement of white adipose tissue caused by caloric excess. The depot-specific adaptation of white adipose tissue in individuals resistant to obesity despite a high-calorie diet is crucial for understanding the pathogenesis of obesity and related metabolic disorders. Our aim was to characterize the metabolic and morphological state of obesity resistance and to investigate depot-specific changes in signaling pathways in epididymal visceral (eVAT) and inguinal subcutaneous (iSAT) white adipose tissue of C57BL/6J male mice on a high-fat diet (60 kcal% fats). After 14 weeks, the mice were categorized as obese (at least 30% higher body mass compared to the control group) or obesity-resistant (weight gain below 30%). Biochemical and morphological parameters, as well as histology, and signaling pathways involved in lipid metabolism, inflammation, and insulin sensitivity were investigated in eVAT and iSAT. The results showed unaltered body, total VAT and iSAT mass in obesity-resistant mice despite increased caloric intake. Leptin levels and glucose homeostasis were improved in these animals compared to the obese mice. In both eVAT and iSAT of the obesity-resistant mice, adipocyte size and lipolytic capacity were retained at control levels, while compared to the obese mice, preserved capacity for adipogenesis, improved local insulin sensitivity and the absence of inflammation were observed only in the eVAT. In conclusion, metabolic adaptation of eVAT rather than iSAT may have a substantial impact on the maintenance of the obesity-resistant phenotype with fewer metabolic complications, which could contribute to the improvement of existing obesity therapies.

FSH, LH, lipid and adipokines in Polycystic Ovary Syndrome: Clinical biochemistry insights for diagnosis and management

Polycystic Ovary Syndrome (PCOS) is a common endocrine syndrome characterized by hormonal imbalances, metabolic disturbances, and clinical symptoms. The pathophysiology of this syndrome involves disruptions in hormonal signaling, particularly changes in levels of luteinizing hormone (LH), and follicle-stimulating hormone (FSH) which can lead to anovulation and infertility. Additionally, insulin resistance and dysfunctional adipose tissue are other complicating factors of this condition. Biochemical markers such as FSH, LH, lipid profiles, and adipokines (like leptin and adiponectin) are crucial for diagnosing PCOS and assessing its severity. In PCOS patients, elevated LH levels relative to FSH are typically observed, and lipid abnormalities increase the risk of cardiovascular diseases. Diagnosing this syndrome usually requires comprehensive biochemical tests to confirm hyperandrogenism and insulin resistance. Management strategies include lifestyle modifications and pharmacological interventions aimed at correcting hormonal imbalances and dyslipidemia. Monitoring treatment outcomes through biochemical markers is essential for evaluating therapeutic efficacy. This review article examines the roles of FSH and LH hormones, lipids, and adipokines in the diagnosis and management of PCOS, emphasizing the importance of clinical biochemistry in improving diagnostic and treatment methods for this disorder. Furthermore, research into identifying emerging biomarkers for early diagnosis and new therapeutic targets is suggested.

The multifaceted role of agents counteracting metabolic syndrome: A new hope for gastrointestinal cancer therapy

Metabolic syndrome (MetS) is defined by the presence of at least three of five clinical parameters including abdominal obesity, insulin resistance, elevated triglycerides, reduced high-density lipoprotein (HDL) and hypertension. Major features describing MetS have been recognized risk factors for cancer onset, with an alarming impact on gastrointestinal (GI) tumors. Intriguingly, therapeutic administration of drugs to improve glycemic control and dyslipidemia (including metformin, statins) has been shown to have a preventive role in the development and in prognosis improvement of several cancer types. Overall, these observations highlight the key role of altered metabolism prevalently in cancer risk development and unveil anti-MetS agent repurposing potential beyond their conventional pharmacological action. The objective of this review is to summarize the current knowledge about the antitumor activity of anti-diabetic and anti-lipemic agents in GI cancer onset and progression. Here, pre-clinical evidence of their therapeutic potential and of their integration in novel compelling therapeutic strategies will be discussed. Possible clinical outcomes of these novel therapeutic combined protocols specifically dedicated to GI cancer patients will be put under the spotlight. In the future, these novel therapeutic options should be considered to improve conventional chemotherapy response and prognosis of this group of patients.

Adiponectin: its role in diabetic and pancreatic cancer

Adiponectin (ApN) is an antidiabetic and anti-inflammatory protein synthesized by adipose tissue. It is essential in regulating insulin sensitivity, glucose, and lipid metabolism by controlling AMPK, PPARα, and MAPK signals. It is an anti-inflammatory property that protects pancreatic β-cells. Often, low levels of ApN are linked to obesity, type II diabetes and the development of PDAC. However, changes in lifestyle and the use of certain drugs can improve ApN function and insulin sensitivity. PDAC is a highly aggressive cancer linked to obesity, type II diabetes, and insulin resistance. ApN plays a complex role in PDAC progression and can suppress PDAC development by weakening β-catenin signaling. Decreases in ApN levels are associated with increased PDAC risk in diabetic patients. PDAC and diabetes are interconnected through the development of insulin resistance, islet dysfunction, change in immunological response, inflammation, oxidative stress, and altered hormone secretion. Genetic studies highlight specific genes like HNF4G and PDX1 that influence both conditions and miRNAs such as miR-19a promote tumor progression through the PI3K/AKT pathway. This review discusses the role of ApN in diabetes and PDAC and the interrelation between diabetes and PDAC.

Obesity, white adipose tissue and cancer

White adipose tissue (WAT) is crucial for whole-body energy homeostasis and plays an important role in metabolic and hormonal regulation. While healthy WAT undergoes controlled expansion and contraction to meet the body's requirements, dysfunctional WAT in conditions like obesity is characterized by excessive tissue expansion, alterations in lipid homeostasis, inflammation, hypoxia, and fibrosis. Obesity is strongly associated with an increased risk of numerous cancers, with obesity-induced WAT dysfunction influencing cancer development through various mechanisms involving both systemic and local interactions between adipose tissue and tumors. Unhealthy obese WAT affects circulating levels of free fatty acids and factors like leptin, adiponectin, and insulin, altering systemic lipid metabolism and inducing inflammation that supports tumor growth. Similar mechanisms are observed locally in an adipose-rich tumor microenvironment (TME), where WAT cells can also trigger extracellular matrix remodeling, thereby enhancing the TME's ability to promote tumor growth. Moreover, tumors reciprocally interact with WAT, creating a bidirectional communication that further enhances tumorigenesis. This review focuses on the complex interplay between obesity, WAT dysfunction, and primary tumor growth, highlighting potential targets for therapeutic intervention.

Zein and Trimethyl Chitosan-Based Core-Shell Nanoparticles for Quercetin Oral Delivery to Enhance Absorption by Paracellular Pathway in Obesity Mice

Quercetin as a flavonoid polyphenol in nature has shown great anti-obesity effects. Due to its poor stability in chemical structure and low intestinal absorption, the in vivo bioavailability of quercetin is considered to be the main challenge for applications. To achieve the oral quercetin administration, chitosan was successfully trimethylated (TMC) to coat the quercetin-loaded zein nanoparticles (Zein-Q), which were designed as the core-shell structure for enhancing the intestinal absorption in this study. TMC-Zein-Q was demonstrated to protect quercetin from degradation and showed the sustained-release effect in an in vitro drug release experiment. The nanoparticles were found to reversibly open tight junctions between intestinal epithelial cells and help to increase quercetin uptake via the paracellular pathway in Caco-2 cells. In addition, the delivery system also showed stronger intestinal permeability and mucoadhesion in vivo, which improved the bioavailability of quercetin in cellular and animal experiments. After 10 weeks of intervention, TMC-Zein-Q could effectively suppress weight gain, improve serum lipid levels, and ameliorate hepatic steatosis and glucose tolerance in high-fat diet (HFD) mice by mediating the AMPK pathway. Consequently, this work successfully constructed TMC-Zein-Q for oral quercetin delivery, providing a novel and feasible strategy for the treatment of obesity via the oral route.

Lipid Profile Alterations in Pediatric Patients with Vitamin D Deficiency

Background/Objectives: Vitamin D deficiency in children has been linked to various metabolic disturbances, including dyslipidemia, which contributes to cardiovascular risk. This study aims to investigate the relationship between vitamin D levels and lipid profiles in children. Methods: A cohort of 332 children with either normal vitamin D or diagnosed vitamin D deficiency was recruited. Serum vitamin D levels were measured, and lipid profiles, including total cholesterol, low-density lipoproteins (LDLs), high-density lipoproteins (HDLs), and triacylglycerols (TAGs), were assessed. The data were analyzed using statistical methods. Results: This study found that children with higher serum vitamin D concentrations had significantly lower TAG (p = 0.033) and very-low-density lipoprotein (VLDL) (p = 0.038) levels and higher HDL levels (p = 0.042), indicating a more favorable lipid profile compared to those with lower vitamin D levels. Conclusions: This study demonstrates that vitamin D deficiency can be associated with dyslipidemia in children. These findings suggest that vitamin D supplementation may be an effective strategy for managing dyslipidemia and reducing cardiovascular risk in pediatric populations. Further research is needed to determine the long-term effects and optimal dosing of vitamin D in this context.

Luteolin Relieves Metabolic Dysfunction-Associated Fatty Liver Disease Caused by a High-Fat Diet in Rats Through Modulating the AdipoR1/AMPK/PPARγ Signaling Pathway

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a significant global public health issue. Luteolin possesses several beneficial biological properties, including antioxidation and anti-inflammation. This study investigated luteolin's effect and potential mechanisms on MAFLD in high-fat diet (HFD)-fed rats. Rats were administered an HFD supplemented with fructose for 12 weeks to induce MAFLD. After that, the HFD-fed rats were given either luteolin (50 or 100 mg/kg/day) or metformin (100 mg/kg/day) for 4 weeks. Luteolin improved metabolic parameters induced by the HFD, since it decreased body weight, blood pressure, fasting blood glucose, serum insulin, free fatty acids, cholesterol, and triglyceride levels (p < 0.05). Luteolin reduced hepatic injury and inflammatory markers in HFD-fed rats (p < 0.05). Additionally, HFD-fed rats treated with luteolin showed reduced malondialdehyde and raised catalase activity in plasma (p < 0.05). Luteolin attenuated hepatic steatosis compared to the untreated rats (p < 0.05). Luteolin also increased plasma adiponectin levels accompanied by upregulation of adiponectin receptor 1 (AdipoR1), AMP-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor γ (PPAR-γ) protein expression in liver (p < 0.05). These findings revealed that luteolin ameliorated HFD-induced MAFLD in rats, possibly by reducing metabolic alterations and oxidative stress and restoring AdipoR1, AMPK, and PPARγ protein expression in HFD-fed rats.

Rational Design of Site-Specific Fatty Acid Derivatives to Extend the Half-Life of Fibroblast Growth Factor 21

Fibroblast growth factor 21 (FGF21) is a crucial regulator of glucose and lipid metabolism, showing significant therapeutic promise for metabolic disorders. However, its clinical application is limited by poor pharmacokinetics. One potential strategy to improve its half-life is to facilitate albumin binding through fatty acid derivation. Despite this promise, achieving site-specific modifications of FGF21 while preserving its biological activity has been challenging. In this study, we applied a rational design approach to create site-specific fatty acid derivatives of FGF21, guided by the structure of the FGF21-receptor complex. This strategy successfully enhances albumin binding without interfering with receptor interactions. The modified FGF21 derivatives exhibited dramatically extended half-lives in mice, increasing from 0.73 h to 11.36 and 13.36 h, respectively. Furthermore, these analogues showed superior biological activity in the presence of albumin, outperforming the C-terminal-derived variant zalfermin. This rational design approach not only improves the pharmacokinetic profile of FGF21 but also provides a framework for enhancing the therapeutic potential of other small proteins.

Mycobacterium abscessus resides within lipid droplets and acquires a dormancy-like phenotype in adipocytes

Mycobacterium abscessus (M. abscessus) is an emerging, rapidly growing mycobacterium that causes chronic lung infection, particularly in patients with cystic fibrosis, as well as skin and soft tissue infections. Adipose tissue is recognized as an important niche that supports M. tuberculosis persistence. However, the dormancy, latency, and persistence mechanisms of M. abscessus in the host remain poorly understood. This study investigated how adipose tissue serves as a niche for M. abscessus using both a human adipose tissue ex vivo infection model and a murine adipose tissue in vivo infection model. M. abscessus infected not only the cytosol of adipocytes but also entered host lipid droplets, where it formed intracytoplasmic lipid inclusions in the bacterial cell. To our knowledge, this unique localization has never been reported for M. abscessus or any other mycobacterium. Within host lipid droplets, M. abscessus lost acid-fastness and gained Nile Red positivity. These results suggest that M. abscessus acquires a dormancy-like phenotype within host lipid droplets of adipocytes, potentially contributing to its persistence, virulence, and resistance to treatment. These findings provide valuable insights into mycobacterial persistence mechanisms and could offer a promising foundation for developing novel therapeutic approaches.

An Alternatively Translated Isoform of PPARG Suggests AF-1 Domain Inhibition as an Insulin Sensitization Target

ARTICLE HIGHLIGHTS

Genetic screens were performed across PPARG to study how disruptive mutations across the full coding sequence affect function. An alternative translational start site in PPARG generates a truncated isoform, peroxisome proliferator-activated receptor γ (PPARγ) M135, which lacks the N-terminal activation function 1 (AF-1) domain and shows increased agonist-induced transactivation of target genes. In human carriers of rare PPARG variants, AF-1 domain-disrupting genetic variants increase agonist-induced PPARγ activity and decrease metabolic syndrome severity. Targeting the AF-1 domain is a potential therapeutic strategy for insulin sensitization.

Physiological Fatty Acid-Stimulated Insulin Secretion and Redox Signaling Versus Lipotoxicity

Significance: Type 2 diabetes as a world-wide epidemic is characterized by the insulin resistance concomitant to a gradual impairment of β-cell mass and function (prominently declining insulin secretion) with dysregulated fatty acids (FAs) and lipids, all involved in multiple pathological development. Recent Advances: Recently, redox signaling was recognized to be essential for insulin secretion stimulated with glucose (GSIS), branched-chain keto-acids, and FAs. FA-stimulated insulin secretion (FASIS) is a normal physiological event upon postprandial incoming chylomicrons. This contrasts with the frequent lipotoxicity observed in rodents. Critical Issues: Overfeeding causes FASIS to overlap with GSIS providing repeating hyperinsulinemia, initiates prediabetic states by lipotoxic effects and low-grade inflammation. In contrast the protective effects of lipid droplets in human β-cells counteract excessive lipids. Insulin by FASIS allows FATP1 recruitment into adipocyte plasma membranes when postprandial chylomicrons come late at already low glycemia. Future Directions: Impaired states of pancreatic β-cells and peripheral organs at prediabetes and type 2 diabetes should be revealed, including the inter-organ crosstalk by extracellular vesicles. Details of FA/lipid molecular physiology are yet to be uncovered, such as complex phenomena of FA uptake into cells, postabsorptive inactivity of G-protein-coupled receptor 40, carnitine carrier substrate specificity, the role of carnitine-O-acetyltransferase in β-cells, and lipid droplet interactions with mitochondria. Antioxid. Redox Signal. 42, 566-622.

An Overview of Sarcopenia: Focusing on Nutritional Treatment Approaches

Sarcopenia is a syndrome characterized by the progressive and generalized loss of skeletal muscle mass and strength. This condition is associated with physical disability, decreased quality of life, and increased mortality. Therefore, reducing the prevalence of sarcopenia could significantly lower healthcare costs. Sarcopenia can be classified into primary and secondary sarcopenia. The former is related to aging and begins after the fourth decade of life; after that, there is a muscle loss of around 8% per decade until age 70 years, which subsequently increases to 15% per decade. On the other hand, secondary sarcopenia can affect all individuals and may result from various factors including physical inactivity, malnutrition, endocrine disorders, neurodegenerative diseases, inflammation, and cachexia. Understanding the multiple mechanisms involved in the onset and progression of sarcopenia allows for us to develop strategies that can prevent, treat, or at least mitigate muscle loss caused by increased protein breakdown. One potential treatment of sarcopenia is based on nutritional interventions, including adequate caloric and protein intake and specific nutrients that support muscle health. Such nutrients include natural food rich in whey protein and omega-3 fatty acids as well as nutritional supplements like branched-chain amino acids, β-hydroxy-β-methylbutyrate, and vitamin D along with food for special medical purposes. It is important to emphasize that physical exercises, especially resistance training, not only promote muscle protein synthesis on their own but also work synergistically with nutritional strategies to enhance their effectiveness.

Interferon regulatory factor 3 beyond innate immunity: Regulation in obesity and metabolic disorders

Interferon regulatory factor 3 (IRF3) is a transcription factor known primarily for its role in antiviral immunity via regulation of type I interferons (IFNs). Recent research has broadened its significance to encompass metabolic disorders, particularly obesity and diabetes. Obesity is characterized by chronic low-grade inflammation, insulin resistance, and metabolic dysfunction, all of which are increasingly found to be associated with immune signaling pathways. IRF3 has emerged as an important regulator in the development of obesity and type 2 diabetes (T2D), predominantly through its regulation of inflammatory cytokines production in various cells in adipose tissue. In obese individuals, IRF3 is activated in the adipocytes and adipose tissue macrophages, to promote the expression of inflammatory cytokines, thereby contributing to chronic inflammation and exacerbating insulin resistance. Moreover, IRF3 has been linked to mitochondrial dysfunction in hepatic disorders, further amplifying metabolic stress and imbalances associated with obesity. The growing evidence suggests that IRF3 is an important mediator in both immune and metabolic pathways, highlighting its potential as a target for the development of therapeutic interventions for obesity-related inflammation and metabolic dysfunction.

Chronic Obstructive Pulmonary Disease and Type 2 Diabetes Mellitus: Complex Interactions and Clinical Implications

Chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM) are highly prevalent chronic conditions, frequently coexisting due to their shared pathophysiological mechanisms and risk factors. Epidemiological studies estimate that up to 30% of COPD patients have comorbid T2DM, contributing to worsened disease progression, more hospitalizations, and higher mortality rates. Systemic inflammation in COPD contributes to insulin resistance by increasing pro-inflammatory cytokines (TNF-α, IL-6, and CRP), which impair glucose metabolism and beta-cell function. Conversely, hyperglycemia in T2DM exacerbates oxidative stress, leading to endothelial dysfunction, reduced lung function, and impaired pulmonary repair mechanisms. A comprehensive narrative review was conducted to evaluate the interplay between COPD and T2DM, examining shared pathophysiological mechanisms, clinical consequences, and management strategies. The co-occurrence of COPD and T2DM accelerates disease development, elevates hospitalization rates, and deteriorates overall prognosis. Pharmacological interactions complicate illness treatment, requiring a multidisciplinary therapy strategy. Recent data underscore the need to integrate palliative care, facilitate shared decision-making, and provide psychological support to enhance patient outcomes. Efficient therapy of COPD-T2DM comorbidity necessitates a customized, interdisciplinary strategy that targets both respiratory and metabolic health. Preliminary prognostic dialogues, palliative care, and holistic lifestyle modifications can improve patient quality of life and clinical results.

Alleviating effect of Lactobacillus fermentum E15 on hyperlipidemia and hepatic lipid metabolism in zebrafish fed by a high-fat diet through the production of short-chain fatty acids

Introduction

Hyperlipidemia is regarded as one of the crucial factors leading to atherosclerosis and other cardiovascular diseases. Gut microbiota plays an important role in regulating host lipid metabolism. Nevertheless, the exact mechanisms behind this remain unclear.

Methods

In the present study, a hyperlipidemic zebrafish model was established using a high-cholesterol diet (HCD) to evaluate the anti-hyperlipidemic effects of Lactobacillus fermentum E15 (L. fermentum E15).

Results

Results showed that L. fermentum E15 effectively reduced lipid accumulation in the blood vessels and liver of HCD-fed zebrafish larvae. Meanwhile, L. fermentum E15 improved abnormal lipid levels, and normalized liver enzyme activity. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis revealed that L. fermentum E15 downregulated the expression of sterol regulatory element-binding factor (SREBP-1), peroxisome proliferator-activated receptor-gamma (PPAR-γ), and fatty acid synthase (Fasn), while upregulated peroxisome proliferator-activated receptor-alpha (PPAR-α). Additionally, metabolomic analysis revealed that L. fermentum E15 produced a series of short-chain fatty acids (SCFAs), including acetic acid, propionic acid, butyric acid, and isovaleric acid. Notably, isovaleric acid contributed to the reduction of lipid droplet accumulation in the liver and blood vessels of HCD-fed zebrafish larvae. In contrast, blocking G-protein coupled receptor 43 (GPR43) with pertussis toxin (PTX) abolished the effects of L. fermentum E15 and isovaleric acid on reducing lipid accumulation in HCD-fed zebrafish larvae. RT-qPCR results further suggested that both L. fermentum E15 and isovaleric acid promoted the expression of GPR43 and leptin A, which was inhibited by PTX.

Conclusion

These findings suggested that L. fermentum E15 alleviates HCD-induced hyperlipidemia by activating GPR43 through SCFAs.

Regulation of adipokine and batokine secretion by dietary flavonoids, as a prospective therapeutic approach for obesity and its metabolic complications

Traditionally recognised as the energy reservoir and main site of adaptive thermogenesis, white and brown adipose tissues are complex endocrine organs regulating systemic energy metabolism via the secretion of bioactive molecules, termed "adipokines" and "batokines", respectively. Due to its significant role in regulating whole-body energy metabolism and other physiological processes, adipose tissue has been increasingly explored as a feasible therapeutic target for obesity. Flavonoids are one of the most significant plant polyphenolic compounds holding a great potential as therapeutic agents for combating obesity. However, understanding their mechanisms of action remains largely insufficient to formulate therapeutic theories. This review critically discusses scientific evidence highlighting the role of flavonoids in ameliorating obesity-related metabolic complications, including adipose tissue dysfunction, inflammation, insulin resistance, hepatic steatosis, and cardiovascular comorbidities in part by modulating the release of adipokines and batokines. Further discussion advocates for the use of therapeutics targeting these bioactive molecules as a potential avenue for developing effective treatment for obesity and its adverse metabolic diseases such as type 2 diabetes.

Adiponectin Prevents Skin Inflammation in Rosacea by Suppressing S6 Phosphorylation in Keratinocytes

Numerous recent evidence highlights epidemiological connections between rosacea and metabolic disorders. However, the precise path through which metabolic factors impact rosacea risk is still unclear. Therefore, this study aims to investigate the role of adiponectin, a crucial adipokine that regulates metabolic homeostasis, in the pathogenesis of rosacea. We elucidated a detrimental feedback loop between rosacea-like skin inflammation and decreased levels of skin adiponectin. To elaborate, rosacea lesional skin exhibits diminished adiponectin expression compared with nonlesional areas in the same patients. Induction of rosacea-like inflammation reduced adiponectin levels in the skin by generating inflammatory cytokines that suppress adiponectin production from subcutaneous adipocytes. Conversely, complete depletion of adiponectin exacerbated rosacea-like features in the mouse model. Mechanistically, adiponectin deficiency led to heightened S6 phosphorylation, a marker of the mTORC1 signaling pathway, in the epidermis. Adiponectin significantly inhibited S6 phosphorylation in cultured keratinocytes. Notably, replenishing adiponectin whole protein or topically applying an agonist for adiponectin receptor 1 successfully improved rosacea-like features in mice. This study contributes to understanding the role of adiponectin in skin inflammation associated with rosacea pathophysiology, suggesting that restoring adiponectin function in the skin could be a potential therapeutic strategy.

Emerging biomarkers in type 2 diabetes mellitus

Diabetes mellitus is a chronic condition caused by high blood glucose resulting from insufficient insulin production or cellular resistance to insulin action or both. It is one of the fastest-growing public health concerns worldwide. Development of long-term nephropathy, retinopathy, neuropathy, and cardiovascular disease are some of the complications commonly associated with poor blood glycemic control. Type 2 diabetes mellitus (T2DM), the most prevalent type of diabetes, accounts for around 95 % of all cases globally. Although middle-aged or older adults are more likely to develop T2DM, its prevalence has grown in children and young people due to increased obesity, sedentary lifestyle and poor nutrition. Furthermore, it is believed that more than 50 % of cases go undiagnosed annually. Routine screening is essential to ensure early detection and reduce risk of life-threatening complications. Herein, we review traditional biomarkers and highlight the ongoing pursuit of novel and efficacious biomarkers driven by the objective of achieving early, precise and prompt diagnoses. It is widely acknowledged that individual biomarkers will inevitably have certain limitations necessitating the need for integrating multiple markers in screening.

Effect of Polyphenol Supplementation on Adiposity: A Systematic Review of Randomized Clinical Trials

PURPOSE OF REVIEW

The obesity is a multifactorial disease, result of high adiposity and excessive body fat, with closed relation to the development of other chronic disease. The growing obesity-related costs has relevant public health impact. In turn, the polyphenol is a dietary bioactive compound with recognized antioxidant propriety and healthy benefits. The polyphenol supplementation can be a promising strategy for obesity treatment, due to its potential antiadipogenic and metabolic control effects, improving quality of life of this population. This systematic review evaluated the effect of polyphenol supplementation on adiposity in overweight adults and elderly people (Systematic Review Registration: CRD42024586193).

RECENT FINDINGS

Current research demonstrates that polyphenol supplementation resulted in a significant decrease in markers of central adiposity (percentage of body fat, fat mass, waist circumference) and visceral adiposity (visceral adipose tissue). The mechanisms may be involved in the activation of lipid turnover pathways, AMPK activation and suppression of transcription factors (SREBPs, PPAR-γ and C/EBP-α) and key enzymes in lipid synthesis in adipose tissue. Furthermore, polyphenol supplementation has also beneficial effects on controlling of blood pressure, blood glucose and lipid profile, contribute to the prevention of other chronic metabolic disorders. Adiposity refers to the distribution of body fat, closely related to cardiometabolic risk, while polyphenols are phytochemicals with potential health-promoting effects. However, the role of these bioactive compounds in controlling adiposity is not well established. This systematic review presents antiadipogenic and metabolic control effects of the dietary polyphenol supplementation. However, there is no consensus on a specific dosage or form of presentation that generates the best results. Further studies are needed to elucidate better the potential effect of these compounds and related-pathway, to perform clinical validation of their use, and to establish the benefits of their long-term use.

Revealing rutaecarpine's promise: A pathway to parkinson's disease relief through PPAR modulation

The pathological mechanisms of Parkinson's disease (PD) is complex, and no definitive cure currently exists. This study identified Rutaecarpine (Rut), an alkaloid extracted from natural plants, as a potential therapeutic agent for PD. To elucidate its mechanisms of action and specific effects in PD, network pharmacology, molecular docking, and experimental validation methods were employed. Our findings demonstrated the efficacy of Rut in ameliorating PD symptoms. Network pharmacology analysis indicated that Rut exerts its therapeutic effects through the PPAR signaling pathway and the lipid pathway. Molecular docking results revealed that Rut forms stable protein-ligand complexes with PPARα and PPARγ. Animal experiments showed that Rut improved motor function in PD mice, protected dopaminergic neurons, ameliorated lipid metabolism disorders, and reduced neuroinflammation. This study identified the critical molecular mechanisms and therapeutic targets of Rut in the treatment of PD, providing a theoretical foundation for future investigations into the pharmacodynamics of Rut as a potential anti-PD agent.

Adipose tissue-derived microRNA-450a-5p induces type 2 diabetes mellitus by downregulating DUSP10

Type 2 diabetes mellitus (T2DM) has rapidly increased worldwide, emerging as the fifth leading cause of death. The treatment of T2DM is challenging due to the side effects of oral hypoglycemic drugs and the limited efficacy of long-term insulin therapy, which can lead to insulin resistance (IR). Consequently, there is significant in discovering new drugs that have minimal side effects and a pronounced hypoglycemic effect. In obesity, microRNA levels have been implicated in glucose metabolism disorders and T2DM, although many aspects remain unresolved. Here, we confirmed that visceral adipose tissue and serum microRNA-450a-5p content increased under obesity and T2DM, and it was significantly positively associated with fasting blood glucose, triglycerides, cholesterol, low-density lipoproteins-cholesterol levels of the subjects. In high-fat diet (HFD)-induced obese mice, microRNA-450a-5p expression was increased in the serum, liver, and white adipose tissue. Moreover, the adipose Dicer-knockout mouse model was constructed to identify adipose tissue as the main source of microRNA-450a-5p. microRNA-450a-5p could inactivate the insulin signal pathway by targeting the inhibited Dual Specificity Phosphatase 10 (DUSP10) and inducing IR and glucose metabolism disorders in vitro cultured hepatocytes and adipocytes. Additionally, microRNA-450a-5p was found to regulate DUSP10 expression and insulin signaling activity, influencing glucose tolerance and insulin sensitivity across various models, including normal diet, HFD-induced obese, adipose tissue-specific microRNA-450a-5p-knockout, and db/db mice. Furthermore, gallic acid might play a potential role in inhibiting glucose levels by decreasing microRNA-450a-5p expression. Thus, microRNA-450a-5p emerges as an attractive therapeutic target for addressing obesity, IR, and T2DM.

The hidden impact of GLP-1 receptor agonists on endometrial receptivity and implantation

Increasing infertility rates represent a growing medical challenge in modern societies resulting from a complex interplay of sociocultural trends, lifestyle factors, exposure to environmental toxins, and underlying health problems. Women's fertility is particularly vulnerable to these shifts. The obesogenic lifestyle not only accelerates weight gain, but also disrupts ovulation driving the rise in infertility. Among several medications used for treating obesity and type 2 diabetes, glucagon-like peptide-1 receptor agonists (GLP-1RAs) show promising improvement in female fertility most likely by stimulating ovulation. However, the effects of GLP-1RAs on the endometrium remain unclear. Further studies are needed to investigate the impact of GLP-1RAs on endometrial receptivity and embryo implantation and early development. The aim of this study is to address the knowledge gap regarding the effects of GLP-1RAs on human reproduction, with special focus on the endometrium. Understanding these mechanisms may help to develop new strategies for improving fertility treatment, reduce implantation failure and address potential safety concerns regarding teratogenicity and adverse developmental outcomes for children born to women conceiving during or soon after GLP-1RA treatment.

Impact of obesity and diabetes on colorectal cancer in Saudi Arabia is associated with liver γ‑glutamyl transferase abnormality

Colorectal cancer (CRC) is a leading global cause of death. In Saudi Arabia, it is the most common cancer among men and the third most common among women. Obesity, diabetes and CRC have become significant health concerns. The present study aimed to explore the connection between liver function markers, obesity and diabetes in patients with CRC. In addition to exploring whether the incidence of CRC had increased in Saudi Arabia. The present study conducted a retrospective chart review based on data from the Saudi Ministry of National Guard Hospitals. Clinical laboratory assays of patients with CRC with obesity and/or diabetes between 2015 and 2021 were analysed, and various factors were considered. This study found that CRC is more prevalent in overweight and obese individuals, primarily aged 50 years and older. Diabetes was more common in patients with CRC (61.76%) compared with non-diabetic individuals (38.24%). Additionally, the protein γ-glutamyl transferase might serve as a potential biomarker for CRC in overweight and obese patients. Notably, the age of CRC diagnosis in Saudi Arabian patients in the present study was lower than previously reported. The present study provided insight into the relationship between obesity, diabetes and liver function markers in Saudi Arabian patients with CRC. It also highlighted the increasing incidence of CRC in Saudi Arabia, emphasizing the need for further attention and research.

Association between the triglyceride glucose body mass index and asthma: evidence from NHANES 2011-2018

BACKGROUND

Asthma is a common chronic respiratory disease whose increasing prevalence poses a significant burden to human health and the economy. Several studies indicate that insulin resistance (IR) is associated with asthma development. The triglyceride-glucose body mass index (TyG-BMI) is a novel biomarker used to evaluate insulin resistance; however, limited research exists on the relationship between TyG-BMI and asthma. This study aimed to investigate the relationship between TyG-BMI and asthma in U.S. adults.

METHOD

This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) database for the 2011-2018 cycles. The exposure variable was the TyG-BMI of participants at baseline, which was calculated based on triglycerides (TG), fasting blood glucose (FBG), and body mass index (BMI). The primary outcome variable was asthma status, determined via questionnaire. We analyzed participants' baseline characteristics and employed weighted multivariate logistic regression models to assess the correlation between TyG-BMI and asthma. A subgroup analysis was conducted to assess whether the relationship between TyG-BMI and asthma was influenced by other factors.

RESULTS

In total, 8,553 participants were analyzed, revealing a positive association between TyG-BMI and asthma. In the analysis of TyG-BMI as a continuous variable, after adjusting for confounding variables, the Odds ratio (OR)(95% CI) for the association between TyG-BMI and asthma was 1.003. After further dividing TyG-BMI into quartiles and adjusting for potential confounders in Model 3, the prevalence of asthma was 0.561 times higher in those with the highest TyG-BMI than in those in the lowest quartile (OR: 1.561, 95% CI: 1.181, 2.065). There was a significant interaction between asthma and TyG-BMI among subgroups defined by gender, coronary heart disease, and stroke (interaction P < 0.05).

CONCLUSIONS

This cross-sectional study found a positive association between TyG-BMI and asthma. These results suggest that TyG-BMI has the potential to be used as an indicator to monitor the prevalence of asthma, but further longitudinal studies are needed to confirm causality and to assess its utility in the management of long-term comorbidities.

CLINICAL TRIAL NUMBER

Not applicable.

Stress and Strain: Differentiating the Responses to High and Moderate Heat Loads and Subsequent Recovery in Grain-Fed Feedlot Steers-Metabolic Hormones

The extent of endocrine changes in response to various levels of heat stress and subsequent recovery is not well understood. Two cohorts of 12 Black Angus steers were housed in climate-controlled rooms (CCR) and subjected to three thermal periods: PreChallenge (5 d), Challenge (7 d) and Recovery (5 d). PreChallenge and Recovery provided thermoneutral conditions. The Challenge simulated a strong heatwave. Finally, the steers were maintained in outdoor pens for 38 d. Rumen temperature (RumT), respiration rate (RR) and panting score (PS) were intensively measured in the CCR. Dry matter intake (DMI) was determined daily. The steers were bled most days, and a rectal temperature (RecT) was taken also. Plasma concentrations of TSH, prolactin, T3, T4, insulin, leptin and adiponectin were determined. During the Challenge, RumT, RecT, RR and PS rose; DMI was reduced. Plasma T3, T4 and adiponectin levels fell also. In Recovery, RumT, RecT, RR and PS fell below the PreChallenge mean. DMI partially recovered. T4 and adiponectin levels remained suppressed alongside lowered insulin. There were linear relationships between T3 concentration and THI, and T3 and T4 levels and DMI only. We highlight comparisons with previously reported metabolic hormone responses of grain-fed Black Angus steers to a moderate-heat-load challenge.

Effects of exogenous insulin supplementation on lipid metabolism in peripartum obese dairy cows

Cows with high body condition scores experience more severe negative energy balance (NEB) and undergo mobilization of more body fat during the peripartum period, leading to more production of nonesterified fatty acids (NEFA) and β-hydroxybutyric acid (BHBA). Postpartum insulin secretion is lower, and insulin resistance is stronger in obese cows. Exogenous insulin supplementation has been hypothesized as a key approach for regulating NEFA in these cows. In this study, we assessed the effects of exogenous insulin supplementation on lipid metabolism, key genes regulated by insulin, and the underlying regulatory mechanism. We selected 181 periparturient multiparous obese dairy cows for the study. Cows in the insulin group (n = 96) received subcutaneous injections of 200 IU insulin (5 mL) on postpartum days 1 and 7, while cows in the control group (n = 85) received subcutaneous injections of 5 mL physiological saline on the same days. The incidence of ketosis was recorded and compared between the two groups. The results demonstrated that postpartum insulin injections significantly reduced the incidence of type II ketosis and delayed the onset time. Meanwhile, a cohort experiment was conducted on 20 cows selected from 181 field trial cows, with 10 cows in the insulin group and 10 cows in the control group. Blood samples were collected for biochemical indicators and subcutaneous adipose tissue was collected for paraffin-embedding and sectioning and RNA sequencing analysis. The results showed that insulin supplementation postpartum reduced concentrations of NEFA and BHBA as well as BCS loss, but did not affect glucose. Additionally, the expression of SREBF1 in insulin signaling pathway and the downstream-regulated lipogenesis network genes were successfully upregulated in insulin-treated healthy group. High expression of SREBF1 may be a key for postpartum insulin supplementation to improve insulin resistance, significantly reduce NEFA concentrations, and prevent or treat ketosis and fatty liver in obese cows. Postpartum administration of insulin could effectively decrease alterations of adipocytes size, which also fully validates that postpartum insulin supplementation promotes lipogenesis and reduces NEFA release.

Absence of MCJ/DnaJC15 promotes brown adipose tissue thermogenesis

Obesity poses a global health challenge, demanding a deeper understanding of adipose tissue (AT) and its mitochondria. This study describes the role of the mitochondrial protein Methylation-controlled J protein (MCJ/DnaJC15) in orchestrating brown adipose tissue (BAT) thermogenesis. Here we show how MCJ expression decreases during obesity, as evident in human and mouse adipose tissue samples. MCJKO mice, even without UCP1, a fundamental thermogenic protein, exhibit elevated BAT thermogenesis. Electron microscopy unveils changes in mitochondrial morphology resembling BAT activation. Proteomic analysis confirms these findings and suggests involvement of the eIF2α mediated stress response. The pivotal role of eIF2α is scrutinized by in vivo CRISPR deletion of eIF2α in MCJKO mice, abrogating thermogenesis. These findings uncover the importance of MCJ as a regulator of BAT thermogenesis, presenting it as a promising target for obesity therapy.

GSK3β Deficiency Expands Obese Adipose Vasculature to Mitigate Metabolic Disorders

BACKGROUND

Maintaining a well-developed vascular system alongside adipose tissue (AT) expansion significantly reduces the risk of metabolic complications. Although GSK3β (glycogen synthase kinase-3 beta) is known for its role in various cellular processes, its specific functions in AT and regulation of body homeostasis have not been reported.

METHODS

GSK3β-floxed and GSK3α-floxed mice were crossed with adiponectin-Cre mice to generate GSK3β or GSK3α adipocyte-specific knockout mice (GSK3βADKO and GSK3αADKO). A comprehensive whole-body metabolism analysis was performed on obese GSK3βADKO mice induced by a high-fat diet. RNA sequencing was conducted on AT of both obese GSK3βADKO and GSK3αADKO mice. Various analyses, including vessel perfusion studies, lipolysis analysis, multiplex protein assays, in vitro protein phosphorylation assays, and whole-mount histology staining, were performed on AT of obese GSK3βADKO mice. Tube-formation experiments were performed using 3B-11 endothelial cells cultured in the conditional medium of matured adipocytes under hypoxic conditions. Chromatin precipitation and immunofluorescence studies were conducted using cultured adipocytes with GSK3 inhibition.

RESULTS

Our findings provide the first evidence that adipocyte-specific knockout of GSK3β expands AT vascularization and mitigates obesity-related metabolic disorders. GSK3β deficiency, but not GSK3α, in adipocytes activates AMPK (AMP-activated protein kinase), leading to increased phosphorylation and nuclear accumulation of HIF-2α, resulting in enhanced transcriptional regulation. Consequently, adipocytes increased VEGF (vascular endothelial growth factor) expression, which engages VEGFR2 on endothelial cells, promoting angiogenesis, expanding the vasculature, and improving vessel perfusion within obese AT. GSK3β deficiency promotes AT remodeling, shifting unhealthy adipocyte function toward a healthier state by increasing insulin-sensitizing hormone adiponectin and preserving healthy adipocyte function. These effects lead to reduced fibrosis, reactive oxygen species, and ER (endoplasmic reticulum) stress in obese AT and improve metabolic disorders associated with obesity.

CONCLUSIONS

Deletion of GSK3β in adipocytes activates the AMPK/HIF-2α/VEGF/VEGFR2 axis, promoting vasculature expansion within obese AT. This results in a significantly improved local microenvironment, reducing inflammation and effectively ameliorating metabolic disorders associated with obesity.

Sarcopenia and cachexia: molecular mechanisms and therapeutic interventions

Sarcopenia is defined as a muscle-wasting syndrome that occurs with accelerated aging, while cachexia is a severe wasting syndrome associated with conditions such as cancer and immunodeficiency disorders, which cannot be fully addressed through conventional nutritional supplementation. Sarcopenia can be considered a component of cachexia, with the bidirectional interplay between adipose tissue and skeletal muscle potentially serving as a molecular mechanism for both conditions. However, the underlying mechanisms differ. Recognizing the interplay and distinctions between these disorders is essential for advancing both basic and translational research in this area, enhancing diagnostic accuracy and ultimately achieving effective therapeutic solutions for affected patients. This review discusses the muscle microenvironment's changes contributing to these conditions, recent therapeutic approaches like lifestyle modifications, small molecules, and nutritional interventions, and emerging strategies such as gene editing, stem cell therapy, and gut microbiome modulation. We also address the challenges and opportunities of multimodal interventions, aiming to provide insights into the pathogenesis and molecular mechanisms of sarcopenia and cachexia, ultimately aiding in innovative strategy development and improved treatments.

Crosstalk between fat tissue and muscle, brain, liver, and heart in obesity: cellular and molecular perspectives

A high-fat diet and physical inactivity are key contributors to obesity, predisposing individuals to various chronic diseases, such as cardiovascular disease and diabetes, which involve multiple organs and tissues. To better understand the role of multi-organ interaction mechanisms in the rising incidence of obesity and its associated chronic conditions, treatment and prevention strategies are being extensively investigated. This review examines the signaling mechanisms between different tissues and organs, with a particular focus on the crosstalk between adipose tissue and the muscle, brain, liver, and heart, and potentially offers new strategies for the treatment and management of obesity and its complications.

The effect and application of adiponectin in hepatic fibrosis

Hepatic fibrosis, a degenerative liver lesion, significantly contributes to the deterioration and mortality among patients with chronic liver diseases. The condition arises from various factors including toxins, such as alcohol, infections like different types of viral hepatitis, and metabolic diseases. Currently, there are no effective treatments available for liver fibrosis. Recent research has shown that adiponectin (ADPN) exhibits inhibitory effects on hepatic fibrosis. ADPN, an adipocytokine secreted by mature adipocytes, features receptors that are widely distributed across multiple tissues, especially the liver. In the liver, direct effects of ADPN on liver fibrosis include reducing inflammation and regulating hepatic stellate cell proliferation and migration. And its indirect effects include alleviating hepatic endoplasmic reticulum stress and reducing inflammation in hepatic lobules, thereby mitigating hepatic fibrosis. This review aims to elucidate the regulatory role of ADPN in liver fibrosis, explore how ADPN and its receptors alleviate endoplasmic reticulum stress, summarize ADPN detection methods, and discuss its potential as a novel marker and therapeutic agent in combating hepatic fibrosis.

Spotlight on the Mechanism of Action of Semaglutide

Initially intended to control blood glucose levels in patients with type 2 diabetes, semaglutide, a potent glucagon-like peptide 1 analogue, has been established as an effective weight loss treatment by controlling appetite. Integrating the latest clinical trials, semaglutide in patients with or without diabetes presents significant therapeutic efficacy in ameliorating cardiometabolic risk factors and physical functioning, independent of body weight reduction. Semaglutide may modulate adipose tissue browning, which enhances human metabolism and exhibits possible benefits in skeletal muscle degeneration, accelerated by obesity and ageing. This may be attributed to anti-inflammatory, mitochondrial biogenesis, antioxidant and autophagy-regulating effects. However, most of the supporting evidence on the mechanistic actions of semaglutide is preclinical, demonstrated in rodents and not actually confirmed in humans, therefore warranting caution in the interpretation. This article aims to explore potential innovative molecular mechanisms of semaglutide action in restoring the balance of several interlinking aspects of metabolism, pointing to distinct functions in inflammation and oxidative stress in insulin-sensitive musculoskeletal and adipose tissues. Moreover, possible applications in protection from infections and anti-aging properties are discussed. Semaglutide enhancement of the core molecular mechanisms involved in the progress of obesity and diabetes, although mostly preclinical, may provide a framework for future research applications in human diseases overall.

Inter-organ communication is a critical machinery to regulate metabolism and aging

Inter-organ communication (IOC) is a complex mechanism involved in maintaining metabolic homeostasis and healthy aging. Dysregulation of distinct forms of IOC is linked to metabolic derangements and age-related pathologies, implicating these processes as a potential target for therapeutic intervention to promote healthy aging. In this review, we delve into IOC mediated by hormonal signaling, circulating factors, organelle signaling, and neuronal networks and examine their roles in regulating metabolism and aging. Given the role of the hypothalamus as a high-order control center for aging and longevity, we particularly emphasize the importance of its communication with peripheral organs and pave the way for a better understanding of this critical machinery in metabolism and aging.

T-cadherin modulates adipogenic differentiation in mesenchymal stem cells: insights into ligand interactions

Introduction

T-cadherin, a non-canonical member of the cadherin superfamily, was initially identified for its involvement in homophilic recognition within the nervous and vascular systems. Apart from its adhesive function, T-cadherin acts as a receptor for two ligands: LDL, contributing to atherogenic processes, and HMW adiponectin, a hormone with well-known cardiovascular protective properties. However, the precise role of T-cadherin in adipose tissue remains elusive. Previously, we generated Cdh13∆Exon3 mice lacking exon 3 in the Cdh13 gene, which encodes the T-cadherin protein, and characterized their phenotype.

Methods

Using wild-type (WT) and T-cadherin-deficient mice (Cdh13ΔExon3), we isolated and cultured mesenchymal stem cells to explore the role of T-cadherin in adipogenic differentiation. The experimental approaches employed include culturing cells under standard or adipogenic conditions, performing Oil Red O and Nile Red staining followed by quantitative analysis, conducting rescue experiments to reintroduce T-cadherin using lentiviral constructs in T-cadherin-deficient cells combined with automated adipocyte differentiation quantification via a neural network. Additionally, Western blotting, ELISA assays, and statistical analysis were utilized to verify the results.

Results

In this study, we demonstrate for the first time that T-cadherin influences the adipogenic differentiation of MSCs. The presence of T-cadherin dictates distinct morphological characteristics in MSCs. Lack of T-cadherin leads to spontaneous differentiation into adipocytes with the formation of large lipid droplets. T-cadherin-deficient cells (T-/- MSCs) exhibit an enhanced adipogenic potential upon induction with differentiating factors. Western Blot, ELISA assays, and rescue experiments collectively corroborate the conclusion that T-/- MSCs are predisposed toward adipogenic differentiation. We carried out an original comparative analysis to explore the effects of T-cadherin ligands on lipid droplet accumulation. LDL stimulate adipogenic differentiation, while T-cadherin expression mitigates the impact of LDL on lipid droplet accumulation. We also examined the effects of both low molecular weight (LMW) and high molecular weight (HMW) adiponectin on lipid droplet accumulation relative to T-cadherin. LMW adiponectin suppressed lipid droplet accumulation independently of T-cadherin, while the absence of T-cadherin enhanced susceptibility to the suppressive effects of HMW adiponectin on adipogenesis.

Discussion

These findings shed light on the role of T-cadherin in adipogenic differentiation and suggest an interplay with other receptors, such as LDLR and AdipoRs, wherein downstream signaling may be modulated through lateral interactions with T-cadherin.

Sygyzium claviflorum fruit extract preadipocyte differentiation inhibition in 3T3-L1 cells

Objective

Concerns over the increasing number of obese individuals and the associated health risks have prompted therapeutic option explorations. Similarly, this study aimed to establish Sygyzium claviflorum fruit extract (SCFE) anti-adipogenic attributes in 3T3-L1 cells.

Methods

The polyphenolic compounds in SCFE were identified with Reverse phase-high performance liquid chromatography (RP-HPLC). Meanwhile, murine 3T3-L1 preadipocytes, measuring leptin levels, reactive oxygen species (ROS), and lipid and triglyceride (TG) contents were utilized during anti-adipogenic activity assessments. Concurrently, the effects of SCFE on adipogenic transcription factors were established with quantitative real-time-polymerase chain reaction (qRT-PCR).

Results

The RP-HPLC results indicated three polyphenolic compounds in SCFE, including one flavonoid (naringin) and two phenolic acids (syringic and p-coumaric). Although SCFE treatments (250-1000 μg/mL) did not result in cell toxicity, they significantly reduced dose-dependent lipid accumulation, ROS production, and TG and leptin levels relative to control-differentiated adipocytes. Moreover, SCFE suppressed sterol regulatory element binding protein-1 (SREBP-1), peroxisome proliferator-activated receptor-gamma (PPAR-γ), and CCAAT/enhancer-binding protein-alpha (C/EBP-α) gene expressions during preadipocyte differentiation into adipocytes.

Conclusion

The findings revealed the anti-adipogenic properties of SCFE, indicating its potential as a natural obesity management remedy. Nevertheless, more studies are necessary to elucidate the reactions resulting in SCFE anti-adipogenic effects and the active constituents responsible for the property.

Cross-talk between adipose tissue and microbiota-gut-brain-axis in brain development and neurological disorder

The gut microbiota is an important factor responsible for the physiological processes as well as pathogenesis of host. The communication between central nervous system (CNS) and microbiota occurs by different pathways i.e., chemical, neural, immune, and endocrine. Alteration in gut microbiota i.e., gut dysbiosis causes alteration in the bidirectional communication between CNS and gut microbiota and linked to the pathogenesis of neurological and neurodevelopmental disorder. Therefore, now-a-days microbiota-gut-brain-axis (MGBA) has emerged as therapeutic target for the treatment of metabolic disorder. But, experimental data available on MGBA from basic research has limited application in clinical study. In present study we first summarized molecular mechanism of microbiota interaction with brain physiology and pathogenesis via collecting data from different sources i.e., PubMed, Scopus, Web of Science. Furthermore, evidence shows that adipose tissue (AT) is active during metabolic activities and may also interact with MGBA. Hence, in present study we have focused on the relationship among MGBA, brown adipose tissue, and white adipose tissue. Along with this, we have also studied functional specificity of AT, and understanding heterogeneity among MGBA and different types of AT. Therefore, molecular interaction among them may provide therapeutic target for the treatment of neurological disorder.

Advances in body composition and gender differences in susceptibility to frailty syndrome: Role of osteosarcopenic obesity

There is general consensus that an improper diet negatively impacts health and that nutrition is a primary tool for the prevention of non-communicable diseases. Unfortunately, the importance of studying body composition, which can reveal early predictors of gender-related diseases, is still not well understood in this context. Currently, individuals are still classified as obese based solely on their body mass index, without considering the amount of fat, its distribution, and the quantity of muscle and bone mass. In this regard, the body composition phenotype defined as "osteosarcopenic obesity" affects approximately 6-41 % of postmenopausal women, with prevalence increasing with age due to the hormonal and metabolic changes that occur during this period. This particular phenotype arises from the strong relationship between visceral fat, muscle, bone, and gut microbiota and predispose postmenopausal women to frailty. Frailty is a complex clinical phenomenon with significant care and economic implications for our society. Recent studies suggest that women have a higher prevalence of frailty syndrome and its individual components, such as osteoporosis, fractures and sarcopenia, compared to men. Here, we provide a comprehensive overview of recent advances regarding the impact of gender on body composition and frailty. Furthermore, we reflect on the crucial importance of personalized nutritional interventions, with a focus on reducing visceral fat, increasing protein intake and optimizing vitamin D levels. A review of the scientific literature on this topic highlights the importance of studying body composition for a personalized and gender-specific approach to nutrition and dietetics, in order to identify frailty syndrome early and establish personalized treatments. This new method of researching disease predictors could likely help clarify the controversial results of studies on vitamin D, calcium and proteins, translate into practical wellness promotion across diverse elderly populations.

Evidence from clinical studies of leptin: current and future clinical applications in humans

Leptin has been established as the prototype adipose tissue secreted hormone and as a major regulator of several human physiology functions. Here, we are primarily reviewing the findings from studies in humans involving leptin administration. We are describing the metabolic, endocrine and immunologic effects of leptin replacement in conditions of leptin deficiency, such as short-term fasting in healthy individuals, relative energy deficiency in sports (REDS), congenital leptin deficiency (CLD), generalized (GL) and partial lipodystrophy (PL), HIV-associated lipodystrophy (HIV-L) and of leptin treatment in conditions of leptin excess (common obesity, type 2 diabetes, steatotic liver disease). We are comparing the results with the findings from preclinical models and present the main conclusions regarding the role of leptin in human physiology, pathophysiology and therapeutics. We conclude that, in conditions of energy deficiency, leptin substitution effectively reduces body weight and fat mass through reduction of appetite, it improves hypertriglyceridemia, insulin resistance and hepatic steatosis (especially in GL and PL), it restores neuroendocrine function (especially the gonadotropic axis), it regulates adaptive immune system cell populations and it improves bone health. On the contrary, leptin treatment in conditions of leptin excess, such as common obesity and type 2 diabetes, does not improve any metabolic abnormalities. Strategies to overcome leptin tolerance/resistance in obesity and type 2 diabetes have provided promising results in animal studies, which should though be tested in humans in randomized clinical trials.

Plasma Non-Esterified Fatty Acid Levels Throughout Childhood and Its Relationship with Leptin Levels in Children

Background/Objective: The relationship of non-esterified fatty acid (NEFA) levels with obesity and obesity-related alterations shows age-dependent variability in children. Leptin, with an important role in energy homeostasis and lipid metabolism, may be related to NEFA levels throughout the first decades of life. This cross-sectional study aims to analyse plasma NEFA levels in children of different ages and evaluate the relationship of leptin with NEFA levels depending on age. Methods: The study sample included 818 prepubertal children (age 6-8 years) and 762 adolescents (age 13-16 years). NEFA levels were measured using the Wako NEFA-C kit. Insulin and leptin levels were determined by IRMA and ELISA, respectively, using commercial kits. Results: The results of the study were found to show that NEFA levels were significantly higher (p < 0.001) in prepubertal children than in children aged 13 to 16 years (0.68 ± 0.3 mmol/L vs. 0.42 ± 0.2 mmol/L, respectively, in males; 0.71 ± 0.3 mmol/L vs. 0.44 ± 0.2 mmol/L, respectively, in females), showing a progressive decrease according to years of life in this cohort of adolescent in both sexes. Leptin and insulin correlated negatively with NEFA levels in younger children but not in older participants. The negative association between NEFA levels and leptin occurring in prepubertal children remained significant when adjusting for insulin. Conclusions: Besides reporting that NEFA levels decrease between the prepubertal age and adolescence, our findings indicate that, in children aged 6-8 years, leptin is associated with NEFA levels, independently of insulin. However, this relationship is not present in older children. Further studies analysing these associations according to pubertal status would be useful to deepen our understand of these findings.

Endurance Exercise Training Alters Lipidomic Profiles of Plasma and Eight Tissues in Rats: a MoTrPAC study

Endurance exercise training (ExT) induces metabolic, structural, and functional adaptations via lipidomic modifications, yet the systematic elucidation of lipidome alterations in response to ExT remains incomplete. As a part of the Molecular Transducers of Physical Activity Consortium (MoTrPAC), we leveraged non-targeted and targeted lipidomics for the systematic discovery of lipid alterations in the brown adipose tissue, heart, hippocampus, kidney, liver, lung, skeletal muscle gastrocnemius, subcutaneous white adipose tissue, and plasma in response to 1, 2, 4 or 8 weeks of ExT in 6-month-old male and female Fischer-344 rats. This study demonstrates that these tissues, each with distinct lipidomic features, underwent dynamic, sexually dimorphic lipid remodeling. Exercise trained animals showed reduced whole-body adiposity and improved cardiorespiratory fitness, along with enhanced utilization of lipid stores and dynamic triacylglycerol remodeling compared to sedentary controls in all tissues except hippocampus. They also showed modifications in phospholipids, lysophospholipids, oxylipins, and ceramides in several tissues. Coordinated changes across tissues reflect systemic tissue communication, with liver-plasma-heart connection potentially playing a key role in systemic lipid metabolism during ExT. These data will improve our understanding of lipid-associated biological processes underlying the health-promoting benefits of ExT.

Loss of MER Tyrosine Kinase Attenuates Adipocyte Hypertrophy and Leads to Enhanced Thermogenesis in Mice Exposed to High-Fat Diet

Obesity is characterized by low-grade inflammation that originates predominantly from the expanding visceral adipose tissue, in which adipocytes respond to lipid overload with hypertrophy, and consequently die by apoptosis. Recruited adipose tissue macrophages (ATMs) take up the excess lipids and remove the dead cells; however, long-term exposure to high concentrations of lipids alters their phenotype to M1-like ATMs that produce pro-inflammatory cytokines and resistin leading to insulin resistance and other obesity-related pathologies. Mer tyrosine kinase is expressed by macrophages and by being an efferocytosis receptor, and by suppressing inflammation, we hypothesized that it might play a protective role against obesity. To our surprise, however, the loss of Mer protected mice against high-fat diet (HFD)-induced obesity. We report in this paper that Mer is also expressed by adipocytes of both white and brown adipose tissues, and while its activity facilitates adipocyte lipid storage both in vitro and in vivo in mice exposed to HFD, it simultaneously attenuates thermogenesis in the brown adipose tissue contributing to its 'whitening'. Our data indicate that Mer is one of the adipocyte tyrosine kinase receptors, the activity of which contributes to the metabolic decision about the fate of excess lipids favoring their storage within the body.

The role of adiponectin-AMPK axis in TDP-43 mislocalization and disease severity in ALS

Hypermetabolism is a prominent characteristic of ALS patients. Aberrant activation of AMPK, an energy sensor regulated by adiponectin, is known to cause TDP-43 mislocalization, an early event in ALS pathogenesis. This study aims to evaluate the association between key energy mediators and clinical severity in ALS patients. We found that plasma adiponectin levels were significantly higher in ALS patients with ALSFRS-R scores below 38 compared to controls (p = 0.047). Additionally, adiponectin concentration was inversely correlated with ALSFRS-R scores (p = 0.021). Immunofluorescence staining of PBMCs revealed negative associations between AMPK activation, TDP-43 mislocalization, and ALSFRS-R scores. We then examined the hypothesis that adiponectin may activate the AMPK-TDP-43 axis in motor neurons. Our results demonstrated that adiponectin treatment of NSC34 cells and HiPSC-MNs induced AMPK activation and TDP-43 mislocalization in an adiponectin receptor-dependent manner. Collectively, these findings suggest that elevated plasma adiponectin may enhance AMPK activation, leading to TDP-43 mislocalization in both PBMCs and motor neurons of ALS patients. This highlights the potential involvement of the adiponectin-AMPK-TDP-43 axis in the dysregulated energy balance observed in ALS.

Visceral Adipocyte-Derived Extracellular Vesicle miR-27a-5p Elicits Glucose Intolerance by Inhibiting Pancreatic β-Cell Insulin Secretion

Pancreatic β-cell dysfunction caused by obesity can be associated with alterations in the levels of miRNAs. However, the role of miRNAs in such processes remains elusive. Here, we show that pancreatic islet miR-27a-5p, which is markedly increased in obese mice and impairs insulin secretion, is mainly delivered by visceral adipocyte-derived extracellular vesicles (EVs). Depleting miR-27a-5p significantly improved insulin secretion and glucose intolerance in db/db mice. Supporting the function of EV miR-27a-5p as a key pathogenic factor, intravenous injection of miR-27a-5p-containing EVs showed their distribution in mouse pancreatic islets. Tracing the injected adeno-associated virus (AAV)-miR-27a-5p (AAV-miR-27a) or AAV-FABP4-miR-27a-5p (AAV-FABP4-miR-27a) in visceral fat resulted in upregulating miR-27a-5p in EVs and serum and elicited mouse pancreatic β-cell dysfunction. Mechanistically, miR-27a-5p directly targeted L-type Ca2+ channel subtype CaV1.2 (Cacna1c) and reduced insulin secretion in β-cells. Overexpressing mouse CaV1.2 largely abolished the insulin secretion injury induced by miR-27a-5p. These findings reveal a causative role of EV miR-27a-5p in visceral adipocyte-mediated pancreatic β-cell dysfunction in obesity-associated type 2 diabetes mellitus.

ARTICLE HIGHLIGHTS

Effect of Aeromonas hydrophila infection on leptin receptor overlapping transcript expression in Rana amurensis

The leptin receptor overlapping transcript (LepROT) has been suggested to play several roles in immunomodulatory mechanisms; however, the understanding of its role in Rana amurensis immunity is still very limited. Here, we performed hematoxylin-eosin staining, quantitative reverse-transcription polymerase chain reaction (qRT-PCR), immunofluorescence and western blotting to investigate the roles of LepROT in the immunomodulatory mechanism and the influence of its expression on the nuclear factor-kappa B (NF-κB) signaling pathway, such as the activation of IκB kinase and NF-кB, in amphibian resistance to infection with Aeromonas hydrophila (Ah). After Ah infection, the liver, lung, kidney, skin, muscle, and stomach of R. amurensis showed cell structure disturbance, bleeding, and texture abnormalities. In addition, the relative expression levels of LepROT, NF-кB, IKKα, and IKKβ were all upregulated after Ah infection; however, they showed time-dependent differential expression. The NF-кB signaling pathway exhibited robust expression levels, which might be explained by the positive feedback regulation function of LepROT. Overall, this study provides a basis for further assessment of the biological functions of LepROT and highlights its role in the regulation of immune mechanisms.

Depot-specific mRNA expression programs in human adipocytes suggest physiological specialization via distinct developmental programs

Adipose tissue is distributed in diverse locations throughout the human body. Not much is known about the extent to which anatomically distinct adipose depots are functionally distinct, specialized organs, nor whether depot-specific characteristics result from intrinsic developmental programs, as opposed to reversible physiological responses to differences in tissue microenvironment. We used DNA microarrays to compare mRNA expression patterns of isolated human adipocytes and cultured adipose stem cells, before and after ex vivo adipocyte differentiation, from seven anatomically diverse adipose tissue depots. Adipocytes from different depots display distinct gene expression programs, which are most closely shared with anatomically related depots. mRNAs whose expression differs between anatomically diverse groups of depots (e.g., subcutaneous vs. internal) suggest important functional specializations. These depot-specific differences in gene expression were recapitulated when adipocyte progenitor cells from each site were differentiated ex vivo, suggesting that progenitor cells from specific anatomic sites are deterministically programmed to differentiate into depot-specific adipocytes. Many developmental transcription factors show striking depot-specific patterns of expression, suggesting that adipocytes in each anatomic depot are programmed during early development in concert with anatomically related tissues and organs. Our results support the hypothesis that adipocytes from different depots are functionally distinct and that their depot-specific specialization reflects distinct developmental programs.

Black Ginger Extract Suppresses Fat Accumulation by Regulating Lipid Metabolism in High-Fat Diet-Fed Mice

This study investigated the antiobesity effects of black ginger extract (BGE) in high-fat diet (HFD)-induced obese mice. Mice were divided into six groups: normal diet control (NC, AIN-93G normal diet), 60% HFD control (HFD), HFD containing metformin at 250 mg/kg b.w. (Met, positive control), and HFD containing BGE at 5, 10, or 20 mg/kg b.w. for 15 weeks. BGE administration significantly prevented HFD-induced increases in weight gain, organ weight, and adipose tissue mass. Furthermore, it resulted in decreased adipogenesis and lipogenesis-related factors, including phosphorylated mitogen-activated protein kinase, peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding proteins, sterol regulatory element-binding protein 1, phosphorylated cAMP response element-binding protein, glucose-6-phosphate dehydrogenase, fatty acid synthase, dephosphorylated ATP-citrate lyase, dephosphorylated acetyl-CoA carboxylase, and lipoprotein lipase, in white adipose tissues. Moreover, BGE administration enhanced lipolysis in white adipose tissue, as evidenced by elevated levels of adipose triglyceride lipase, phosphorylated hormone-sensitive lipase, and protein kinase A, along with reduced levels of perilipin and phosphodiesterase 3B. BGE induced thermogenesis in brown adipose tissues, as reflected by the increased expression of AMP-activated protein kinase, uncoupling protein 1, and carnitine palmitoyltransferase 1 and decreased levels of fatty acid-binding protein 4. In conclusion, this study provides comprehensive evidence supporting the antiobesity effects of BGE, elucidating the underlying molecular mechanisms involved in preventing weight gain, suppressing adipogenesis, promoting lipolysis, and stimulating thermogenesis. These findings suggest the potential therapeutic utility of BGE in combating obesity and associated metabolic disorders (KHGASP-2023-034).

Adipose Tissue Plasticity: A Comprehensive Definition and Multidimensional Insight

Adipose tissue is composed of adipocytes, stromal vascular fraction, nerves, surrounding immune cells, and the extracellular matrix. Under various physiological or pathological conditions, adipose tissue shifts cellular composition, lipid storage, and organelle dynamics to respond to the stress; this remodeling is called "adipose tissue plasticity". Adipose tissue plasticity includes changes in the size, species, number, lipid storage capacity, and differentiation function of adipocytes, as well as alterations in the distribution and cellular composition of adipose tissue. This plasticity has a major role in growth, obesity, organismal protection, and internal environmental homeostasis. Moreover, certain thresholds exist for this plasticity with significant individualized differences. Here, we comprehensively elaborate on the specific connotation of adipose tissue plasticity and the relationship between this plasticity and the development of many diseases. Meanwhile, we summarize possible strategies for treating obesity in response to adipose tissue plasticity, intending to provide new insights into the dynamic changes in adipose tissue and contribute new ideas to relevant clinical problems.