Metabolic Messengers: Adiponectin

Safety and efficacy of GLP-1/FGF21 dual agonist HEC88473 in MASLD and T2DM: A randomized, double-blind, placebo-controlled study

BACKGROUND & AIMS

Glucagon-like peptide-1 (GLP-1) and fibroblast growth factor 21 (FGF21) are key regulators of glucose and lipid metabolism. In the present study, we assessed the safety and efficacy of a novel GLP-1/FGF21 dual agonist HEC88473 for the treatment of metabolic dysfunction-associated steatotic liver disease (MASLD) combined with type 2 diabetes mellitus (T2DM).

METHODS

This was a randomized, double-blind, placebo-controlled, multiple-ascending-dose phase Ib/IIa trial. Sixty patients with MASLD and T2DM were randomized (10:2) to receive HEC88473 (5.1, 15.3, 30.6, 45.9, or 68.0 mg) or placebo via weekly subcutaneous injection for 5 weeks.

RESULTS

After 5 weeks of treatment with HEC88473, MRI-proton density fat fraction (MRI-PDFF) was reduced in a dose-proportional manner. The largest relative mean change reached -47.21% (p = 0.0143) in the 30.6 mg cohort, compared with -15.05% in the placebo group, with a higher proportion of >30% relative reductions in patients with baseline PDFF >8%. The 5-week treatment with HEC88473 significantly reduced levels of HbA1c (glycated hemoglobin), as well as fasting and postprandial glucose levels. The largest mean change in HbA1c was -1.10% in the 68.0 mg cohort, compared with -0.31% in the placebo group. Improvement was also observed in participants' lipid profiles. Most adverse events were mild to moderate in severity. The most frequently reported adverse events were gastrointestinal disorders (n = 29, 48.3%).

CONCLUSIONS

Herein, we report the clinical safety and proof-of-concept data for the GLP-1/FGF21 dual agonist HEC88473. A 5-week treatment with HEC88473 was generally safe and well tolerated, with multiple positive effects observed, including reduced liver fat, and improved glycemic control, insulin resistance and lipid metabolism, together indicating comprehensive improvement in metabolic syndrome.

IMPACT AND IMPLICATIONS

In this randomized, double-blind, placebo-controlled phase Ib/IIa study, we assessed clinical safety, pharmacodynamic and pharmacokinetic data of the GLP-1/FGF21 dual agonist HEC88473 in patients with MASLD (metabolic dysfunction-associated steatotic liver disease) and T2DM (type 2 diabetes mellitus). HEC88473 was generally safe and well tolerated. The GLP-1/FGF21 dual agonist significantly reduced the hepatic fat fraction assessed using MRI-proton density fat fraction, and improved glycemic control and lipid profiles with only 5 weeks' treatment, leading to comprehensive improvement in metabolic syndrome. The present results suggest that HEC88473 could be a promising treatment option in this patient population.

CLINICAL TRIAL NUMBER

Chinese Drug Trial Identifier (http://www.chinadrugtrials.org.cn/index.html): CTR20211088.

CLINICALTRIALS

GOV: NCT05943886.

Zingiberaceae in Cardiovascular Health: A review of adipokine modulation and endothelial protection via adipocyte-endothelial crosstalk mechanism

PURPOSE OF THE REVIEW

Although adipose tissue controls metabolism and protects vital organs, its importance to general health is being highlighted by the rise in type 2 diabetes and cardiovascular disease. Adipokines produced by adipose cells are essential regulators of metabolism, glucose homeostasis, and inflammatory response. It also protects vascular endothelial cells for its potential implications for cardiovascular protection. Understanding its intricate involvement in adipose tissue-endothelial communication is critical in developing targeted therapeutics to treat cardiovascular conditions linked with obesity and metabolic dysregulation. Spices from the Zingiberaceae family, such as cardamom, turmeric, and ginger, have anti-inflammatory and anti-oxidant properties that help reduce oxidative stress, vascular dysfunction, and adipocyte-endothelial crosstalk which are all linked to the etiology of CVD. Comprehensive molecular insights into how they modulate adipokine signalling, inflammatory pathways, and ROS-induced adipocyte-vascular interactions remain unexplored, demanding additional translational and clinical validation. With an emphasis on patients with obesity and metabolic dysregulation, the investigation aims to elucidate the mechanisms by which the spice as whole/bioactive constituents of the Zingiberaceae family may provide protection against CVD by integrating previous studies.

RECENT FINDINGS

Current research continues to support the use of spices from the Zingiberaceae family, such as ginger, turmeric, cardamom, and pepper, as potential therapeutic agents for addressing metabolic complications like obesity, type II diabetes, and CVDs. These natural remedies may modulate adipocyte-endothelial crosstalk and inflammation by modulating important signalling pathways such as AMPK, AKT, PPAR, and NF-κB..

CONCLUSION

This review provides a complete summary of existing knowledge, opening the way for future research and prospective therapeutic applications of Zingiberaceae spices in cardiovascular health management.

Adiponectin receptor agonist adipoRon alleviates imiquimod-induced murine psoriasis

Psoriasis is a chronic inflammatory skin disease involving inflammation, immune responses and keratinocytes proliferation. It has been suggested that adiponectin/adiponectin receptor 1 (AdipoR1) signaling plays a role in regulating psoriatic skin inflammation. AdipoRon is a small molecule agonist of AdipoR1 and AdipoR2. The effect of adipoRon on psoriasis has not been elucidated. In this study, using a GEO database, we found that the expression of adiponectin was substantially decreased in skin lesions of psoriasis patients. This reduction was also validated in an imiquimod-induced psoriasis mouse model. Interestingly, we found that topical administration of adipoRon significantly ameliorated skin lesions induced by imiquimod. The critical pro-inflammatory cytokines (IL-6, IL-17A and IL-23) and the infiltration of macrophages, especially M1 macrophages were dramatically decreased while the infiltration of M2 macrophages were slightly increased in the skin lesions upon adipoRon treatment. Mechanistically, adipoRon inhibited macrophage inflammation and keratinocytes proliferation via activation of AMPK signaling pathway. Collectively, our study demonstrates that adipoRon displayed anti-inflammatory activity and anti-proliferation of keratinocytes, and attenuated psoriatic response. Activating AdipoR1 signaling pathway by adipoRon or others may represent a novel therapeutic approach to psoriasis.

Evaluating miR-107 and adiponectin as biomarkers in obstructive sleep apnea: Associations with neurotransmitters and metabolic regulation

This study aimed to examine the levels of microRNA-107 (miR-107) and its correlation with neurotransmitters (glutamate, serotonin, melatonin) and adiponectin in patients with obstructive sleep apnea (OSA) compared to healthy controls. The results showed that serum levels of miR107, melatonin, and adiponectin were significantly lower in OSA patients compared to controls, while serotonin and glutamate levels were significantly higher. Spearman correlation analysis revealed that in the control group, miR-107 levels were moderately correlated with glutamate (negative) and adiponectin (positive), but these associations were disrupted in the OSA group. Receiver operating characteristic (ROC) curve analysis demonstrated that miR-107 had excellent diagnostic performance, with 100% sensitivity and 89.3% specificity at a cut-off of 3.0 ng/mL. Adiponectin also showed strong diagnostic potential, with 78% sensitivity and 89% specificity. In contrast, serotonin, melatonin, and glutamate exhibited more moderate diagnostic accuracy. These findings suggest that miR-107 and adiponectin could serve as promising biomarkers for diagnosing OSA, and targeting miR-107 to modulate metabolic factors may offer novel therapeutic approaches for improving OSA management.

Obesity, White Adipose Tissue, and Adipokines Signaling in Male Reproduction

Currently, obesity is a global pandemic characterized by systemic metabolic complications that negatively impact several organs, including white adipose tissue (WAT) and the tissues of the male reproductive system. Since the discovery of leptin in 1994, WAT has been recognized as a dynamic endocrine organ for secreting a series of molecules with hormonal functions, collectively called adipokines. The link between obesity, WAT, adipokines, and the male reproductive system is direct and little explored. With changes in nutritional status, WAT undergoes morphofunctional changes, and the secretion of adipokines is altered, negatively impacting reproductive mechanisms, including steroidogenesis and spermatogenesis. In this review, we address in an updated way the structural and functional characteristics of WAT as well as the link between obesity and changes in the signaling pathways of the adipokines leptin, adiponectin, resistin, visfatin, apelin, chemerin, omentin-1, vaspin, and asprosin in male reproduction. Understanding the relationship between obesity, these adipokines, and reproductive dysfunction can contribute to new strategies for the treatment of subfertility and male infertility.

Integrin Trafficking, Fibronectin Architecture, and Glomerular Injury upon Adiponectin Receptor 1 Depletion

Key Points

Glomerular expression of adiponectin receptor 1 (AdipoR1) was lower in people with type 2 diabetes and correlates with podocyte loss. AdipoR1 knockout induced glomerular injury and fibrosis in mice, predominantly in males. AdipoR1 knockdown podocytes showed impaired trafficking of active integrin β 1, fibronectin accumulation, impaired adhesion, and increased apoptosis.

Background

Deficiency of adiponectin and its downstream signaling may contribute to the pathogenesis of kidney injury in type 2 diabetes. Adiponectin activates intracellular signaling using adiponectin receptor 1 (AdipoR1) and adiponectin receptor 2, but the role of adiponectin receptor–mediated signaling in glomerular injury in type 2 diabetes remains unknown.

Methods

The expression of AdipoR1 in the kidneys of people with type 2 diabetes and the expression of podocyte proteins or injury markers in the kidneys of AdipoR1 knockout (AdipoR1-KO) mice and immortalized AdipoR1-deficient human podocytes were investigated by immunohistochemistry and immunoblotting. The functional role of AdipoR1 was studied in AdipoR1-deficient podocytes by performing assays for apoptosis, cytokine secretion, mechanical stress, adhesion, and endocytic trafficking.

Results

Glomerular AdipoR1 expression was lower in type 2 diabetes and associated kidney disease, correlating with higher body mass index and podocyte loss. Male AdipoR1-KO mice showed typical signs of early diabetic kidney disease, including albuminuria, glomerular structural abnormalities, and lower expression of central podocyte proteins; females were less affected. Podocyte apoptosis increased in female and male AdipoR1-KO mice, and excessive podocyte loss, potentially due to detachment, was detected in males. AdipoR1 deficiency impaired the yes-associated protein–mediated mechanoresponse and induced accumulation of the extracellular matrix (ECM) protein fibronectin in the glomeruli in vivo and podocytes in vitro . Functionally, AdipoR1 deficiency impaired endocytosis of the ECM receptor active integrin β 1, disturbed focal adhesion turnover, and remodulated podocyte-derived ECM, thereby reducing podocyte adhesion.

Conclusions

AdipoR1 deficiency in mice resulted in the development of kidney injury predominantly in males. Mechanistically, AdipoR1 loss in podocytes impaired endocytosis of active integrin β 1, which plausibly compromised focal adhesion dynamics, disturbed fibronectin matrix turnover, and hindered podocyte adhesion.

The dual challenge of diabesity: pathophysiology, management, and future directions

Diabesity, the concurrent occurrence of obesity and type-2 diabetes mellitus (T2DM), represents a pressing global health challenge characterized by intricate pathophysiological mechanisms and a wide range of associated comorbidities. Central to its development are insulin resistance, metabolic syndrome, and chronic low-grade inflammation mediated by dysregulated adipokine secretion and systemic metabolic dysfunction. These mechanisms underpin the progression of diabesity and its complications, including cardiovascular disease and hypertension. Management strategies encompass lifestyle interventions focusing on tailored dietary modifications and structured physical activity, pharmacological treatments targeting both glycemic control and weight loss, and surgical interventions such as bariatric surgery, which have demonstrated efficacy in achieving durable outcomes. Clinical trials and meta-analyses underscore the comparative advantages of different treatment modalities in terms of efficacy, safety, and sustainability. Moreover, long-term follow-up studies emphasize the critical need for sustained multidisciplinary interventions to prevent relapse and enhance patient outcomes. Future advancements in management include exploring precision medicine approaches that integrate individual metabolic profiles, lifestyle factors, and emerging therapeutic innovations. A multidisciplinary approach combining advanced therapeutic strategies and patient-centered care remains pivotal for optimizing management and improving prognoses for individuals with diabesity. This review highlights the complex interplay between obesity and T2DM, offering comprehensive insights into their pathophysiology, clinical presentation, and management paradigms.

Progression in the In Vitro Macrophage Expansion

Macrophages play essential roles in homeostasis and disease, and they were considered terminally differentiated cells that cannot proliferate. However, growing evidence shows that macrophages can self-renew in homeostasis and multiple pathological states in vivo and artificial induction in vitro. With the rise of immune cell therapy based on macrophages, large-scale in vitro expansion of macrophages has become more and more urgent. However, the proliferation of macrophages in vitro is still inefficient because of the heterogeneity of macrophages, complicated crosstalk between macrophages and their microenvironments, and poor understanding of macrophage proliferation regulations. In this review, we summarized the discoveries known to stimulate macrophage proliferation in vitro, including cytokines, small molecule compounds, metabolites, the composition of pathogens and apoptotic cells, natural product extracts, gene editing, and other factors, as well as related mechanisms. It can be concluded that the promotion of macrophage proliferation in vitro covers various approaches and mechanisms. However, it is still necessary to test more strategies and learn more macrophage proliferation mechanisms to achieve large-scale engineering expansion of macrophages in vitro.

Ceramides may Play a Central Role in the Pathogenesis of Alzheimer's Disease: a Review of Evidence and Horizons for Discovery

While several hypotheses have been proposed to explain the underlying mechanisms of Alzheimer's disease, none have been entirely satisfactory. Both genetic and non-genetic risk factors, such as infections, metabolic disorders and psychological stress, contribute to this debilitating disease. Multiple lines of evidence indicate that ceramides may be central to the pathogenesis of Alzheimer's disease. Tumor necrosis factor-α, saturated fatty acids and cortisol elevate the brain levels of ceramides, while genetic risk factors, such as mutations in APP, presenilin, TREM2 and APOE ε4, also elevate ceramide synthesis. Importantly, ceramides displace sphingomyelin and cholesterol from lipid raft-like membrane patches that connect the endoplasmic reticulum and mitochondria, disturbing mitochondrial oxidative phosphorylation and energy production. As a consequence, the flattening of lipid rafts alters the function of γ-secretase, leading to increased production of Aβ42. Moreover, ceramides inhibit the insulin-signaling cascade via at least three mechanisms, resulting in the activation of glycogen synthase kinase-3 β. Activation of this kinase has multiple consequences, as it further deteriorates insulin resistance, promotes the transcription of BACE1, causes hyperphosphorylation of tau and inhibits the transcription factor Nrf2. Functional Nrf2 prevents apoptosis, mediates anti-inflammatory activity and improves blood-brain barrier function. Thus, various seemingly unrelated Alzheimer's disease risk factors converge on ceramide production, whereas the elevated levels of ceramides give rise to the well-known pathological features of Alzheimer's disease. Understanding and targeting these mechanisms may provide a promising foundation for the development of novel preventive and therapeutic strategies.

Novel insights and an updated review of metabolic syndrome in immune-mediated organ transplant rejection

Metabolic syndrome (MetS) is a group of symptoms that are characterized by abnormal changes in metabolic substances such as glucose, lipids, proteins, and bile acids. MetS is a common complication after organ transplantation and can further affect the survival and physiological function of the graft by reprograming the patient's immune environment. Additionally, MetS can influence the occurrence of post-transplant complications, such as infections. In recent years, research into the epidemiology and mechanisms of MetS has grown significantly. In this review, we summarize the mechanisms of MetS after transplantation and the mechanisms of hyperglycemia, insulin resistance, hyperlipidemia, abnormal bile acids, and abnormal amino acids on the body's immune cells as related to the effect of metabolic disorders on immune rejection after liver, kidney, heart, skin and other organ transplantation. Finally, we provide an overview of current treatment strategies and offer insights into potential future therapies for managing MetS in transplant recipients.

Psoriasis in Obese Adolescents with Diabetes-From Common Molecular Background to Vicious Circle of Metabolic Syndrome-Case Report and Review of Literature

Psoriasis and type 1 diabetes mellitus (T1DM) are chronic autoimmune diseases sharing common immunological pathways, particularly the involvement of interleukin 17 (IL-17), driving Th17-mediated inflammation. This review explores the overlap between psoriasis, obesity, T1DM, and necrobiosis lipoidica (NL), a skin condition associated with diabetes. Obesity exacerbates inflammation through immune cell activation in adipose tissue and the release of proinflammatory adipokines, such as leptin, resistin, and IL-18, which enhance autoimmune responses and insulin resistance. Leptin promotes the differentiation of Th1 and Th17 cells, which are central to autoimmune responses in both psoriasis and T1DM. The coexistence of psoriasis, T1DM, and insulin resistance further complicates metabolic control, increasing the risk of complications like diabetic nephropathy and cardiovascular disease. Biologic treatments targeting IL-17A and IL-17F offer promising therapeutic options for managing both skin and metabolic symptoms. The early identification and management of metabolic risk factors, along with personalized interventions, are essential to improve clinical outcomes in patients with psoriasis and T1DM, particularly in obese individuals. This case report and review highlight the complex interplay of these conditions and emphasize the need for integrated treatment strategies.

Adipokines: masterminds of metabolic inflammation

Adipose tissue is an immunologically active organ that controls host physiology, partly through the release of mediators termed adipokines. In obesity, adipocytes and infiltrating leukocytes produce adipokines, which include the hormones adiponectin and leptin and cytokines such as tumour necrosis factor and IL-1β. These adipokines orchestrate immune responses that are collectively referred to as metabolic inflammation. Consequently, metabolic inflammation characterizes metabolic disorders and promotes distinct disease aspects, such as insulin resistance, metabolic dysfunction-associated liver disease and cardiovascular complications. In this unifying concept, adipokines participate in the immunological cross-talk that occurs between metabolically active organs in metabolic diseases, highlighting the fundamental role of adipokines in obesity and their potential for therapeutic intervention. Here, we summarize how adipokines shape metabolic inflammation in mice and humans, focusing on their contribution to metabolic disorders in the setting of obesity and discussing their value as therapeutic targets.

Adiponectin and All-Cause Mortality in Patients with Chronic Kidney Disease: A Systematic Review and Meta-Analysis

Background/Objectives: Elevated levels of adiponectin in chronic kidney disease (CKD) have been paradoxically associated with increased mortality. This meta-analysis aimed to evaluate the association between circulating adiponectin levels and all-cause mortality in patients with CKD, in total and various subgroups. Methods: We systematically searched PubMed, Embase, and Cochrane Library from their inception to December 2024 for studies examining baseline adiponectin levels and observed mortality outcomes in patients with CKD. Studies were included if they evaluated CKD stages 2-5 patients, measured baseline circulating adiponectin levels, and reported hazard ratios (HRs) for all-cause mortality. We excluded non-original research, studies of acute conditions, normal kidney function, kidney transplantation, and those using log-transformed or standardized HRs. HRs with a 95% confidence interval (CI) for all-cause mortality risk per 1 µg/mL increase in adiponectin were extracted and analyzed using the Comprehensive Meta-Analysis Version 4. Study quality was assessed using the Newcastle-Ottawa Scale. Results: Twelve studies with 2523 subjects were included. The pooled unadjusted HR was 1.003 (95% CI: 0.981-1.025) using a random-effects model (I2 = 79%). Subgroup analyses demonstrated increased mortality risk with elevated adiponectin levels in non-Asia (HR 1.021 [95% CI: 1.006-1.037], p = 0.006), studies with female proportion <47% (HR 1.021 [95% CI: 1.009-1.033], p < 0.001), and studies with body mass index ≥25 kg/m2 (HR 1.023 [95% CI: 1.008-1.038], p = 0.003). In contrast, higher adiponectin levels were associated with decreased mortality risk in the peritoneal dialysis group (HR 0.956 [95% CI: 0.934-0.979], p < 0.001) and female proportion ≥47% group (HR 0.929 [95% CI: 0.874-0.988], p = 0.019). Discussion/Conclusions: This meta-analysis revealed that elevated adiponectin levels have varying associations with the risk of all-cause mortality across CKD patient subgroups. These findings suggest that the prognostic value of adiponectin levels in CKD may be modulated by demographic and clinical factors. Limitations include poor generalizability with underrepresentation of early-stage CKD. This research received no external funding and was not registered.

Alpha-1-Antitrypsin Enhances Fat Graft Survival in a Murine Model

Objective: Fat grafting is widely applied for various purposes, including volume restoration, improving tissue quality, and promoting wound healing, but it has poor long-term graft survival predictability. Alpha-1-antitrypsin (AAT) administration is hypothesized to improve fat graft outcomes by expediting inflammatory resolution and graft vascularity and reducing necrosis. Approach: Mice heterozygote to human AAT was grafted fat under the scalp alongside 400 µg/graft AAT or albumin (ALB) on days 0 and 3. Graft volume was determined by micro-magnetic resonance imaging, and explants were assessed for viability, histology, immunohistochemistry, and expression of selected genes. AAT expression was examined in hypoxia-exposed adipose-derived stem cells (ADSCs). Results: After 90 days, AAT-treated grafts maintained higher volumes (70.06% vs. 34.54%, n = 8, p = 0.02) and displayed improved tissue quality. On day 10 after grafting, grafts exhibited more blood vessels (mean 1.94/mm2 vs. 0.33/mm2) and 6.25-fold more adiponectin transcript levels (n = 12, p = 0.02). Although day-3 interleukin (IL)-1β expression was 5-fold greater in AAT-treated grafts (n = 6, p = 0.4), day-10 IL-1β expression was 2-fold lower compared to ALB-treated grafts (n = 22, p = 0.01). In the Methoxynitrosulfophenyl-tetrazolium carboxanilide (XTT) assay, day-3 AAT-treated grafts were 1.56-fold more metabolically functional (n = 6, p = 0.04) and exhibited greater perilipin-positive regions (18.5% versus 3.1%). Hypoxia-exposed ADSC expressed 9-fold higher AAT transcript levels (p = 0.04). Innovation: Fat grafting outcomes improved by early AAT treatment, probably by accelerating inflammatory resolution. Due to its marked safety profile, the study's findings are for adjunct clinical-grade AAT therapy. Conclusion: AAT has a promising potential to be utilized as a fat graft outcome enhancer in terms of volume retention predictability and tissue quality.

The Molecular Basis of Polycystic Ovary Syndrome and Its Cardiometabolic Correlates: Exploring the Intersection and Its Clinical Implications-A Narrative Review

Recent studies have highlighted the association between polycystic ovary syndrome (PCOS) and cardiometabolic diseases, leading to an improved understanding of the underlying mechanistic factors. PCOS significantly increases cardiovascular risk by predisposing individuals to various subclinical and clinical conditions, including atherosclerosis and type 2 diabetes mellitus. Additionally, it interacts synergistically with other traditional cardiovascular risk factors, such as obesity, hyperlipidemia, and insulin resistance. Several molecular mechanisms involving genetics, epigenetics, adipokine secretion, hyperandrogenemia, and hyperinsulinemia play a role in the relationship between PCOS and these comorbidities. For instance, androgen excess has been implicated in the development of hypertension, type 2 diabetes mellitus, endothelial dysfunction, and ultimately, broader cardiovascular disease. A deeper understanding of these underlying mechanisms facilitates the development of diagnostic, preventative, and therapeutic strategies directed at reducing cardiometabolic morbidity. This narrative review summarizes the current evidence, explores the potential clinical implications of these findings, and discusses emerging therapies to reduce cardiometabolic morbidity in women with PCOS.

The Power of Exercise: Unlocking the Biological Mysteries of Peripheral-Central Crosstalk in Parkinson's Disease

BACKGROUND

Exercise is a widely recognized non-pharmacological treatment for Parkinson's Disease (PD). The bidirectional regulation between the brain and peripheral organs has emerged as a promising area of research, with the mechanisms by which exercise impacts PD closely linked to the interplay between peripheral signals and the central nervous system.

AIM OF REVIEW

This review aims to summarize the mechanisms by which exercise influences peripheral-central crosstalk to improve PD, discuss the molecular processes mediating these interactions, elucidate the pathways through which exercise may modulate PD pathophysiology, and identify directions for future research.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review examines how exercise-induced cytokine release promotes neuroprotection in PD. It discusses how exercise can stimulate cytokine secretion through various pathways, including the gut-brain, muscle-brain, liver-brain, adipose-brain, and bone-brain axes, thereby alleviating PD symptoms. Additionally, the potential contributions of the heart-brain, lung-brain, and spleen-brain axes, as well as multi-axis crosstalk-such as the brain-gut-muscle and brain-gut-bone axes-are explored in the context of exercise therapy. The study highlights the need for further research into peripheral-central crosstalk and outlines future directions to address challenges in clinical PD therapy.

β-Sitosterol modulates osteogenic and adipogenic balance in BMSCs to suppress osteoporosis via regulating mTOR-IMP1-Adipoq axis

BACKGROUND

Osteoporosis (OP) is a prevalent global health concern, impacting millions of individuals, especially the elderly. The etiology of senile OP is associated with the imbalance of osteogenic and adipogenic differentiation in the bone marrow mesenchymal stem cells (BMSCs). The imbalance of BMSCs differentiation fate will leading to bone loss and lipids accumulation. β-sitosterol, a naturally occurring phytosterol which is abundant in plants and has a similar structure to cholesterol, demonstrates diverse bioactivities, including lipid-lowering effect and osteogenesis-inducing effects. These effects indicate that β-sitosterol might have anti-OP effects. Nevertheless, the precise mechanism underlying β-sitosterol's anti-osteoporotic efficacy via modulating BMSCs differentiation fate remains obscure.

PURPOSE

This study endeavors to elucidate whether β-sitosterol has the potential to augment the osteogenic differentiation of BMSCs while mitigating their adipogenic differentiation, thereby exerting an anti-OP effect; and to reveal its molecular mechanisms of action.

METHODS

In this study, a dosage form HP-β-cyclodextrin-coated β-sitosterol was developed for intragastric administration in mice to enhancing its bioavailability. Subsequently by using an integrative approach encompassing bioinformatics, computer molecular simulations, high-throughput sequencing, and in vitro/vivo as well as in-tube experiments, we investigated the anti-osteoporotic and bone healing effects of β-sitosterol and delineated its underlying mechanisms.

RESULTS

Our findings demonstrate that β-sitosterol exhibits anti-osteoporotic and bone healing effects both in vitro and in vivo by modulating the osteogenic and adipogenic differentiation of BMSCs. Mechanistically, these effects are mediated through the direct inhibition of mTOR's kinase activity independent of mediating autophagy, leading to the suppression of the mTOR-IMP1-Adipoq axis in BMSCs.

CONCLUSION

These results unveil β-sitosterol as a promising therapeutic agent for OP, shedding light on its underlying mechanisms. This research contributes potential candidates for diagnostic and therapeutic interventions in the realm of OP.

The role of mechanosignaling in the control of myocardial mass

Regulation of myocardial mass is key for maintaining cardiovascular health. This review highlights the complex and regulatory relationship between mechanosignaling and myocardial mass, influenced by many internal and external factors including hemodynamic and microgravity, respectively. The heart is a dynamic organ constantly adapting to changes in workload (preload and afterload) and mechanical stress exerted on the myocardium, influencing both physiological adaptations and pathological remodeling. Mechanosignaling pathways, such as the mitogen-activated protein kinases (MAPKs) and the phosphoinositide 3-kinases and serine/threonine kinase (PI3K/Akt) pathways, mediate downstream effects on gene expression and play key roles in transducing mechanical cues into biochemical signals, thereby modulating cellular processes, including control of myocardial mass. Dysregulation of these processes can lead to pathological cardiac remodeling, such as hypertrophic cardiomyopathy. Furthermore, recent studies have highlighted the importance of protein quality control mechanisms, such as the ubiquitin-proteasome system, in settings of extreme physiological conditions that alter the heart workload such as pregnancy and microgravity. Overall, this review provides a thorough insight into how mechanical signals are converted into chemical signals to regulate myocardial mass in both healthy and diseased conditions.

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.

Adiponectin targets the AMPK/mTOR signaling pathway to alleviate cognitive impairment in epilepsy

Among patients with chronic epilepsy, 70‑80% have cognitive impairment. To investigate the relationship between adiponectin (ADPN) and the cognitive level in epilepsy and its mechanism, 20 epileptic patients and 20 healthy controls were included for the assessment of the cognitive level. An ELISA was used to evaluate the serum ADPN level. An epileptic rat model was established and treated with AdipoRon, an ADPN receptor (AdipoR) agonist, which binds to AdipoR1 and AdipoR2. The Morris water maze test was used to assess the cognitive function of rats, and the expression levels of the synapsis‑associated proteins postsynaptic density protein 95 (PSD95), synaptosomal associated protein 25 (SNAP25) and synaptophysin (SYP), as well as AMP‑activated protein kinase (AMPK), mTOR, phosphorylated (p‑)AMPK and p‑mTOR were determined by immunoblotting. Serum ADPN levels were positively correlated with the Montreal cognitive assessment score. AdipoRon improved the cognitive function of epileptic rats, maintained the structural integrity of hippocampal neurons and reduced neuronal damage. It also promoted the mRNA expression of AdipoR1 and AdipoR2 in the hippocampus. Furthermore, AdipoRon increased the expression of the synapsis‑associated proteins PSD95, SNAP25 and SYP by activating the AMPK/mTOR signaling pathway. ADPN improved cognitive impairment in epilepsy by targeting the AMPK/mTOR signaling pathway, providing novel insights for the treatment of epilepsy.

AdipoRon ameliorates chronic ethanol induced cardiac necroptosis by reducing ceramide mediated mtROS

Chronic ethanol (EtOH) consumption has been widely recognized as a significant contributor to cardiotoxicity. However, no specific treatment is currently available to ameliorate chronic ethanol induced cardiotoxicity. Adiponectin receptor agonist AdipoRon exerts protective effects in multiple organs through alleviating lipotoxicity. Our previous study showed that chronic ethanol consumption increased de novo ceramide synthesis and necroptosis in myocardium. In this study, we investigated the role of AdipoRon on ceramide metabolism and necroptosis in chronic ethanol-treated myocardium. Eight-week-old C57/BL6J mice were fed with a Lieber-Decarli diet containing vehicle or AdipoRon for 12 weeks. Cardiac function, histology and oxidative stress were assessed. We found that chronic ethanol treatment decreased expression of AdipoR2 in myocardium and H9c2 cells, whereas AdipoRon improved cardiac function, reduced myocardium ceramide levels and suppressed necroptosis. By pharmacological interventions, RNA interference and point mutations in AdipoR2, we demonstrated that AdipoRon reduced ceramide levels through PPARα mediated lipid metabolism rather than AdipoR2's ceramidase activity. Using transmission electron microscope and reactive oxygen species (ROS) staining, we showed that chronic ethanol induced myocardium mitochondria damage and mitochondrial reactive oxygen species (mtROS) accumulation. Meanwhile, we found that AdipoRon ameliorated chronic ethanol induced cardiac necroptosis via the SIRT3-SOD2-mtROS pathway. Moreover, C6 ceramide treatment recapitulated chronic ethanol in inducing mtROS and necroptosis, whereas the ceramide synthesis inhibitors myriocin (MYR) and fumonisin B1 (FB1) attenuated chronic ethanol induced mtROS and necroptosis. Collectively, AdipoRon ameliorates chronic ethanol induced cardiac necroptosis by reducing ceramide de novo synthesis and mtROS, which highlights the therapeutic potential of targeting ceramide metabolism and oxidative stress pathways in treating ethanol induced cardiotoxicity.

Effect of home-based exercise with or without a Mediterranean-style diet on adiposity markers in postmenopausal women: A randomized-control trial

Advancing age and estrogen deficiency increases susceptibility of post-menopausal women (PMW) to abdominal obesity and manifestation of cardiometabolic disease. There is limited evidence on the effect of lifestyle interventions on adiposity markers within at-risk PMW. Therefore, this study aims to evaluates an 8-weeks of home-based, equipment-free, interval training (HEFIT) with or without Mediterranean-style diet (MD) on adiposity markers in physically inactive, postmenopausal women with overweight/obesity. Thirty PMW (56.7 ± 3.9 years, BMI: 30.5 ± 5.2 kg/m2) were randomly assigned to three groups: (i) Ex; HEFIT thrice weekly/week, (ii) EX + MD, or (iii) CTL; control. Visceral Adiposity Index (VAI), body weight, BMI, waist and hip circumference (WC; HC), visceral adipose tissue (VAT), total body fat percentage, leptin, and adiponectin were determined pre- and post-8-week intervention. There was no significant between group effect on VAI. Compared to CTL, a significant between group reduction was seen in weight, BMI, and WC in both EX and EX+D (p < 0.05). Leptin and adiponectin remained unchanged in all groups (p > 0.05). Adherence rates were 85% and 96% for EX and EX+MD, respectively, and 80% of EX+D of participants had optimal adherence to diet. Concluding HEFIT with or without dietary changes could improve adiposity in overweight/obese postmenopausal women.

The Interplay Between Gut Microbiota, Adipose Tissue, and Migraine: A Narrative Review

BACKGROUND

Migraine, a prevalent neurovascular disorder, affects millions globally and is associated with significant morbidity. Emerging evidence suggests a crucial role of the gut microbiota and adipose tissue in the modulation of migraine pathophysiology, particularly through mechanisms involving neuroinflammation and metabolic regulation.

MATERIAL AND METHODS

A narrative review of the literature from 2000 to 2024 was conducted using the PubMed database. Studies addressing the relationships between microbiota, adipose tissue, and migraine-including dietary interventions and their impact-were analyzed.

RESULTS

The findings highlight a bidirectional gut-brain axis, with gut microbiota influencing neuroinflammation via metabolites such as short-chain fatty acids (SCFAs). Obesity exacerbates migraine severity through chronic inflammation and the dysregulation of adipocytokines like leptin and adiponectin. Dietary patterns, such as low glycemic index diets and Mediterranean diets, and the use of prebiotics, probiotics, and postbiotics show potential in migraine management.

CONCLUSIONS

This review underscores the need for integrative approaches targeting the microbiota-gut-brain axis and adipose tissue in migraine therapy. Future studies should explore longitudinal effects and personalized interventions to optimize outcomes.

Treating Metabolic Dysregulation and Senescence by Caloric Restriction: Killing Two Birds with One Stone?

Cellular senescence is a state of permanent cell cycle arrest accompanied by metabolic activity and characteristic phenotypic changes. This process is crucial for developing age-related diseases, where excessive calorie intake accelerates metabolic dysfunction and aging. Overnutrition disturbs key metabolic pathways, including insulin/insulin-like growth factor signaling (IIS), the mammalian target of rapamycin (mTOR), and AMP-activated protein kinase. The dysregulation of these pathways contributes to insulin resistance, impaired autophagy, exacerbated oxidative stress, and mitochondrial dysfunction, further enhancing cellular senescence and systemic metabolic derangements. On the other hand, dysfunctional endothelial cells and adipocytes contribute to systemic inflammation, reduced nitric oxide production, and altered lipid metabolism. Numerous factors, including extracellular vesicles, mediate pathological communication between the vascular system and adipose tissue, amplifying metabolic imbalances. Meanwhile, caloric restriction (CR) emerges as a potent intervention to counteract overnutrition effects, improve mitochondrial function, reduce oxidative stress, and restore metabolic balance. CR modulates pathways such as IIS, mTOR, and sirtuins, enhancing glucose and lipid metabolism, reducing inflammation, and promoting autophagy. CR can extend the health span and mitigate age-related diseases by delaying cellular senescence and improving healthy endothelial-adipocyte interactions. This review highlights the crosstalk between endothelial cells and adipocytes, emphasizing CR potential in counteracting overnutrition-induced senescence and restoring vascular homeostasis.

New insights into constitutive neutrophil death

Neutrophils undergo rapid aging and death known as constitutive or spontaneous death. Constitutive neutrophil death (CND) contributes to neutrophil homeostasis and inflammation resolution. CND has long been considered to be apoptotic until our findings reveal that it was a heterogeneous combination of diverse death. Furthermore, dead neutrophils retain functional roles via multiple manners. This review provides an overview of current research on the mechanism and modulation of CND. More noteworthy, we also summarize the after-death events of neutrophils. The fate of neutrophils can be changed under pathological conditions, so the involvement of CND in diseases and CND-related therapeutic strategies are also addressed.

Iron-Mediated Regulation in Adipose Tissue: A Comprehensive Review of Metabolism and Physiological Effects

PURPOSE OF REVIEW

Review the latest data regarding the intersection of adipose tissue (AT) and iron to meet the needs of AT metabolism and the progression of related diseases.

RECENT FINDINGS

Iron is involved in fundamental biological metabolic processes and is precisely fine-tuned within the body to maintain cellular, tissue and even systemic iron homeostasis. AT not only serves as an energy storage depot but also represents the largest endocrine organ in the human body, maintaining systemic metabolic homeostasis. It is involved in physiological processes such as energy storage, insulin sensitivity regulation and lipid metabolism. As a unique iron-sensing tissue, AT expresses related regulatory factors, including the classic hepcidin, ferroportin (FPN), iron regulatory protein/iron responsive element (IRP/IRE) and ferritin. Consequently, the interaction between AT and iron is intricately intertwined. Imbalance of iron homeostasis produces the potential risks of steatosis, impaired glucose tolerance and insulin resistance, leading to AT dysfunction diseases, including obesity, type 2 diabetes and metabolic dysfunction-associated steatotic liver disease (MASLD). Despite the role of AT iron has garnered increasing attention in recent years, a comprehensive review that systematically organizes the connection between iron and AT remains lacking. Given the necessity of iron homeostasis, emphasizing its potential impact on AT function and metabolism regulation provides valuable insights into physiological effects such as adipocyte differentiation and thermogenesis. Futhermore, regulators including adipokines, mitochondria and macrophages have been mentioned, along with analyzing the novel perspective of iron as a key mediator influencing the fat-gut crosstalk.

Metabolic Syndrome and Somatic Composition: A Large Cross-sectional Analysis

BACKGROUND/AIM

To elucidate the relationship between metabolic syndrome (Mets) and somatic composition [fat mass, fat-free (FF) mass, and fat to fat-free (F-FF) ratio] among health checkup recipients (7,776 males and 10,121 females).

PATIENTS AND METHODS

We classified study subjects into four types considering Japanese criteria for Mets; Type A is for males with waist circumference (WC) <85 cm and females with WC <90 cm, Type B is for males with WC ≥85 cm and females with WC ≥90 cm, but without any metabolic abnormalities, Type C is for males with WC ≥85 cm and females with WC ≥90 cm and one metabolic disorder (pre-Mets), and Type D is Mets. We compared baseline characteristics among types of A, B, C, and D.

RESULTS

F index, FF index, and F-FF ratio showed an increasing trend with increasing risk factors for Mets in both sexes.

CONCLUSION

This study demonstrates a clear correlation between somatic composition and the severity of metabolic syndrome (Mets). As Mets risk factors increase, fat mass, fat-free mass, and the fat-to-fat-free ratio also rise, indicating that body composition shifts with disease progression. These findings emphasize the need for early intervention, such as exercise and diet, to manage somatic composition imbalances and reduce complications like insulin resistance.

Reduction of Hepatic Fat Content by Dulaglutide for the Treatment of Diabetes Mellitus: A Two-Centre Open, Single-Arm Trial

BACKGROUND

With the elevated level of NAFLD prevalence, the incidence of diabetes, hypertension, metabolic syndrome and other diseases is also significantly elevated. GLP-1RA can exert weight loss, glucose-lowering effects and various nonglycaemic effects. However, the relationship between quantitative reduction in hepatic fat content and improvement of pancreatic islet function by GLP-1RA is unclear.

METHODS

This trial was a single-arm open cohort study. A total of 38 patients with T2DM and NAFLD were enrolled in the GLP-1RA treatment group. The included patients were tested for biochemical and blood glucose levels, adiponectin and FGF21 levels, and liver fat content was measured using MRI. Measure the above indicators again after at least 3 months of GLP-1RA treatment. Divided into Q1 (average decrease of 0.37%) and Q2 (average decrease of 8.6%) groups based on the degree of reduction in liver fat content.

RESULTS

Q2 group showed an average reduction in liver fat content of 8.6%, a decrease in glycated haemoglobin of 18.17%, a weight loss of 7.29% and an increase in fasting c-peptide release by 1.03%, 1-h and 2-h postprandial c-peptide release by 28.86% and 18.28% respectively. In contrast, Q1 group had an average reduction in liver fat content of 0.37%, a decrease in glycated haemoglobin of only 6.53%, a weight loss of 3.41%, a decrease in fasting c-peptide release by 1.91% and an increase in 1-h and 2-h postprandial c-peptide release by 19.18% and 11.66% respectively.

CONCLUSION

Reduction in liver fat content effectively improves pancreatic islet function secretion, particularly postprandial c-peptide secretion, especially in the first hour after a meal. This improvement leads to a decrease in glycated haemoglobin levels and promotes better compliance with blood glucose control.

Effects of duration of high-fat diet on adipocyte hyperplasia in rat epididymis

BACKGROUND

High-fat diet (HFD) contributes to obesity and enhances the expression of mature adipocyte markers. However, the effect of HFD on adipocyte hyperplasia remains controversial. This may be due to variations in the duration of HFD. This study aimed to investigate the effects of different durations of HFD on adipocyte hyperplasia and the expression of mature adipocyte-related markers in obese rats.

METHODS

We divided 32 Sprague-Dawley rats into four groups: B (standard diet control), H1 (HFD for four weeks), H2 (HFD for eight weeks), and H3 (HFD for 12 weeks). We evaluated the morphological changes in epididymal fat cells, measured serum inflammatory markers using enzyme-linked immunosorbent assay (ELISA) kits, and quantified adipocyte hyperplasia and maturation markers using western blotting.

RESULTS

We observed progressive increases in body weight, epididymal fat weight, serum leptin, TNF-α, IL-6, irisin, PPARγ, adiponectin, and FNDC5 protein expression over 8 weeks of HFD. 12 weeks of HFD intervention resulted in significant decreases in irisin, PPARγ, adiponectin, and FNDC5. Concurrently, the expression of perilipin A and ATGL declined with prolonged HFD.

CONCLUSIONS

Our results suggest that the duration of HFD significantly affects adipocyte ability to undergo hyperplasia in the epididymis of obese rats. Specifically, 4 weeks of HFD did not change the capacity for adipocyte hyperplasia, while 8 weeks of the diet enhanced this capacity. Interestingly, a longer diet duration (12 weeks) led to a decrease in adipocyte hyperplasia.

Impaired Fibroblast Growth Factor 21 (FGF21) Associated with Visceral Adiposity Leads to Insulin Resistance: The Core Defect in Diabetes Mellitus

The Central nervous system (CNS) is the prime regulator of signaling pathways whose function includes regulation of food intake (consumption), energy expenditure, and other metabolic responses like glycolysis, gluconeogenesis, fatty acid oxidation, and thermogenesis that have been implicated in chronic inflammatory disorders. Type 2 diabetes mellitus (T2DM) and obesity are two metabolic disorders that are linked together and have become an epidemic worldwide, thus raising significant public health concerns. Fibroblast growth factor 21 (FGF21) is an endocrine hormone with pleiotropic metabolic effects that increase insulin sensitivity and energy expenditure by elevating thermogenesis in brown or beige adipocytes, thus reducing body weight and sugar intake. In contrast, during starvation conditions, FGF21 induces its expression in the liver to initiate glucose homeostasis. Insulin resistance is one of the main anomalies caused by impaired FGF21 signaling, which also causes abnormal regulation of other signaling pathways. Tumor necrosis factor alpha (TNF-α), the cytokine released by adipocytes and inflammatory cells in response to chronic inflammation, is regarded major factor that reduces the expression of FGF21 and modulates underlying insulin resistance that causes imbalanced glucose homeostasis. This review aims to shed light on the mechanisms underlying the development of insulin resistance in obese individuals as well as the fundamental flaw in type 2 diabetes, which is malfunctioning obese adipose tissue.

The evolving tumor-associated adipose tissue microenvironment in breast cancer: from cancer initiation to metastatic outgrowth

Adipocytes represent a significant proportion of breast tissue, comprising between 3.7 and 37% of stromal tissue. They play a pivotal role in metabolic regulation, energy supply, metabolic regulation, support effects, and cytokine release within the breast. In breast cancer (BC) tissue, adipocytes engage in intricate crosstalk with BC cells, playing a key role in tumor proliferation, invasion, metastasis formation, and metabolic remodeling. This is due to the provision of hormones, adipokines, and fatty acids to tumor cells by the adipocytes. With the initiation of metastatic outgrowth of BC, the peritumoral adipose tissue exhibits abundant and intricate changes based on its original construction and function, which convert it into a tumor-associated adipose tissue microenvironment (TAAME). It includes some specific adipocytes: adipose-derived stem cells (ASCs), cancer-associated adipocytes (CAAs), adipocyte-derived fibroblasts (ADFs), etc. From a mechanistic standpoint, specific adipocytes can facilitate the proliferation, invasion, metastasis, and angiogenesis of BC cells by secreting a multitude of cytokines (IL-6) and adipokines (leptin), which collectively create an environment conducive to BC progression. It is of paramount importance to recognize the TAAME as a crucial target for the diagnosis, treatment, and drug resistance of BC. Consequently, the review presents an overview of the characteristics and interactions of specific adipocytes within TAAME cell populations. This will facilitate the development of more effective personalized therapies against BC progression, relapse, and metastasis.

Adiponectin deficiency prevents chronic colitis-associated colonic fibrosis via inhibiting CXCL13 production

INTRODUCTION

Colonic fibrosis is a long-term complication of inflammatory bowel disease (IBD), often leading to functional impairment, intestinal obstruction, and surgery. Adiponectin (APN) is an adipokine derived from adipocytes that plays a pleiotropic role in fibrosis regulation, depending on tissue and cell type specific or disease context, but its role in colonic fibrosis remains unclear.

OBJECTIVE

To explore the role and involved mechanism of APN in chronic colitis-associated colonic fibrosis.

METHODS

Studies were performed in GEO database, colonic tissues of UC patients, dextran sulfate sodium (DSS)-induced colonic fibrosis in male wild-type (WT) and APN-/- mice, mouse L929 and human CCD-18Co fibroblasts treated with recombinant CXCL13 protein, and colonic fibrosis in WT mice infected with shRNA of CXCL13.

RESULTS

APN was highly expressed in the colonic tissues of UC patients and positively correlated with the colonoscopy score and colonic fibrosis markers COL1A1 and COL3A1. APN deficiency significantly improved chronic colitis-induced colonic fibrosis in mice with down-regulating collagenase accumulation and expressions of TGF-β, α-SMA, COL1A1, COL3A1, and MMP-9 in colonic tissues. Transcriptomics showed that APN deficiency mainly affected cytokine-cytokine receptor interactions, especially CXCL13 signaling. Follow-up studies showed that APN deficiency significantly decreased the number of colonic F4/80+CD206+CXCL13+ macrophages by weakening Akt phosphorylation. Additional experiments confirmed that CXCL13 notably increased the expressions of α-SMA and COL1A1 in mouse and human fibroblasts by activating p-Akt, p-p38, p-ERK, and p-JNK. Moreover, inhibiting CXCL13 with shRNA significantly ameliorated colonic fibrosis in mice with DSS-induced chronic colitis. Immunohistochemistry analysis revealed high expression of CXCL13 in the colon tissues of patients with UC, showing a positive correlation with APN, COL1A1, and COL3A1.

CONCLUSION

APN contributes to the progression of colonic fibrosis and can exacerbate this condition by regulating the secretion of CXCL13 in the colon, offering potential new perspectives on the pathophysiology of colonic 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.

Adipocyte Angptl8 deletion improves glucose and energy metabolism and obesity associated inflammation in mice

Angiopoietin-like protein 8 (Angptl8), expressed in the liver and adipocytes, forms a complex with Angptl3 or Angptl4, which regulates lipoprotein lipase and triglyceride metabolism. However, the precise functions of adipocyte Angptl8 remain elusive. Here we report that adipocyte-specific inducible Angptl8-knockout (AT-A8-KO) male mice on normal diet showed minor phenotypic changes, but after a high-fat high fructose (HFHF) diet, exhibited decreased body weight gain and glycemia, elevated rectal temperature and early dark phase energy expenditure compared to the Cre controls. AT-A8-KO mice also displayed improved glucose tolerance, a trend for better insulin sensitivity, improved insulin-stimulated glucose uptake in adipose tissues, and reduced visceral adipose tissue crown-like structures, plasma MCP-1 and leptin levels. The results indicate the importance of adipose Angptl8 in the context of nutri-stress and obesity, as its deletion in mice promotes a metabolically healthy obese phenotype by slightly ameliorating obesity, improving glucose and energy homeostasis, and mitigating inflammation.

Endocrine adaptations to demanding physiological states in ruminants

Highly productive ruminants rely on hormonally driven adaptations to prioritize the use of limiting nutrients during the demanding phases of the pregnancy-lactation cycle. Glucose, the predominant oxidative fuel of fetal life and the absolute precursor of mammary lactose synthesis, illustrates the need and benefit of such adaptations. Endocrine mechanisms such as insulin resistance and/or hypoinsulinemia favor the diversion of maternal glucose to the placenta or mammary gland where uptake is independent of insulin. Research in dairy cows in the 1980s and 1990s identified growth hormone as a peripherally acting signal opposing the effects of insulin. The following decades have seen the discovery of a new generation of signals secreted almost exclusively by adipose tissue, skeletal muscle or liver, dynamically regulated by metabolic challenges, and engaged in cross-organ communication. The understanding of these signals in the coordination of metabolism in ruminants has been limited by the availability of assays to measure their circulating concentrations and materials to perform functional studies. Nevertheless, emerging data point to their importance during demanding physiological states in ruminants, including early lactation in dairy cows and late pregnancy in sheep. Examples include modulation of insulin action by liver-derived fibroblast growth factor 21 (FGF21) and regulation of energy allocation among tissues by the action of the adipose-derived hormone leptin via its ability to control the hypothalamic-pituitary-thyroid axis. Recent studies investigating the regulation and action of FGF21 and leptin in dairy cows and sheep will be used to illustrate the potential of recently discovered signals to coordinate metabolism during physiologically demanding states such as early lactation.

Butanolides and clerodane diterpenes from the twigs of Casearia grewiifolia and their effects on adiponectin secretion

Three butanolides derivatives, grewiifolides A-C, and nine clerodane diterpenes, grewiifolins M-U, as well as a known sterol were isolated from the twigs of Casearia grewiifolia. The chemical structures and configurations of all isolates were established by various spectroscopic means and chemical derivatization. In a cell-based phenotypic assay using the adipogenesis model of human bone marrow mesenchymal stem cells (hBM-MSCs), grewiifolide B significantly promoted adiponectin-secretion with EC50 value of 24.8 µM. In target identification studies, butanolide derivatives were selectively bound to PPARγ with Ki values of 4.65, 0.55, and 17.8 µM, respectively. Further functional analysis and molecular modeling revealed that grewiifolide B promotes adiponectin-secretion through PPARγ full agonism.

FK506 binding protein 51: Its role in the adipose organ and beyond

There is a great body of evidence that the adipose organ plays a central role in the control not only of energy balance, but importantly, in the maintenance of metabolic homeostasis. Interest in the study of different aspects of its physiology grew in the last decades due to the pandemic of obesity and the consequences of metabolic syndrome. It was not until recently that the first evidence for the role of the high molecular weight immunophilin FK506 binding protein (FKBP) 51 in the process of adipocyte differentiation have been described. Since then, many new facets have been discovered of this stress-responsive FKBP51 as a central node for precise coordination of many cell functions, as shown for nuclear steroid receptors, autophagy, signaling pathways as Akt, p38 MAPK, and GSK3, as well as for insulin signaling and the control of glucose homeostasis. Thus, the aim of this review is to integrate and discuss the recent advances in the understanding of the many roles of FKBP51 in the adipose organ.

The causal impact of gut microbiota on circulating adipokine concentrations: a two-sample Mendelian randomization study

PURPOSE

Evidence from previous experimental and observational research demonstrates that the gut microbiota is related to circulating adipokine concentrations. Nevertheless, the debate as to whether gut microbiome composition causally influences circulating adipokine concentrations remains unresolved. This study aimed to take an essential step in elucidating this issue.

METHODS

We used two-sample Mendelian randomization (MR) to causally analyze genetic variation statistics for gut microbiota and four adipokines (including adiponectin, leptin, soluble leptin receptor [sOB-R], and plasminogen activator inhibitor-1 [PAI-1]) from large-scale genome-wide association studies (GWAS) datasets. A range of sensitivity analyses was also conducted to assess the stability and reliability of the results.

RESULTS

The composite results of the MR and sensitivity analyses revealed 22 significant causal associations. In particular, there is a suggestive causality between the family Clostridiaceae1 (IVW: β = 0.063, P = 0.034), the genus Butyrivibrio (IVW: β = 0.029, P = 0.031), and the family Alcaligenaceae (IVW: β=-0.070, P = 0.014) and adiponectin. Stronger causal effects with leptin were found for the genus Enterorhabdus (IVW: β=-0.073, P = 0.038) and the genus Lachnospiraceae (NK4A136 group) (IVW: β=-0.076, P = 0.01). Eight candidate bacterial groups were found to be associated with sOB-R, with the phylum Firmicutes (IVW: β = 0.235, P = 0.03) and the order Clostridiales (IVW: β = 0.267, P = 0.028) being of more interest. In addition, the genus Roseburia (IVW: β = 0.953, P = 0.022) and the order Lactobacillales (IVW: β=-0.806, P = 0.042) were suggestive of an association with PAI-1.

CONCLUSION

This study reveals a causal relationship between the gut microbiota and circulating adipokines and may help to offer novel insights into the prevention of abnormal concentrations of circulating adipokines and obesity-related diseases.

Pathological mechanisms and related markers of steroid-induced osteonecrosis of the femoral head

BACKGROUND

Osteonecrosis of the femoral head (ONFH) is a refractory orthopedic disease with a high disability rate. Long-term administration of steroids is the most common pathogenic factor for non-traumatic ONFH. Early diagnosis of steroid-induced osteonecrosis of the femoral head (SONFH) is difficult and mainly depends on imaging.

OBJECTIVES

The objectives of this review were to examine the pathological mechanisms of SONFH, summarize related markers of SONFH, and identify areas for future studies.

METHODS

We reviewed studies on pathological mechanisms and related markers of SONFH and discussed the relationship between them, as well as clinical applications and the outlook of potential markers.

RESULTS

The pathological mechanisms of SONFH included decreased osteogenesis, lipid accumulation, increased intraosseous pressure, and microcirculation disruption. Differential proteomics and genomics play crucial roles in the occurrence, progression, and outcome of SONFH, providing novel insights into SONFH. Additionally, the biological functions of mesenchymal stem cells (MSCs) and exosomes (Exos) in SONFH have attracted increasing attention.

CONCLUSIONS

The pathological mechanisms of SONFH are complex. The related markers mentioned in the current review can predict the occurrence and progression of SONFH, which will help provide effective early clinical prevention and treatment strategies for SONFH.

Ubiquitination and deubiquitination: Implications for the pathogenesis and treatment of osteoarthritis

Osteoarthritis (OA) is a degenerative disease that affects multiple cells and associated extracellular matrix (ECM). Chondrocytes and chondroextracellular matrix together constitute articular cartilage tissue. Any factors that affect the activity of chondrocytes and destroy the metabolic balance of the chondrocyte ECM will lead to the inability of articular cartilage to perform normal functions. The articular subchondral bone and articular cartilage must be coordinated to resist enough friction and mechanical stress, so the articular subchondral bone lesion will aggravate the articular cartilage defect and vice versa. Synoviocytes, including fibroblast-like synoviocytes (FLSs) and synovial macrophages at the joint, are also important factors that cause low-grade chronic progressive inflammation of OA. Regulation of phenotype transformation of synovial macrophages has become another possible target for the clinical treatment of OA. Ubiquitination and deubiquitination are the main post-translational protein modification pathways in the human body, which are widely involved in multiple signaling pathways and physiological processes. Naturally, they also play a very important regulatory role in the occurrence and development of OA. These effects are summarized in this review, including (A) regulating the aging and apoptosis of chondrocytes, FLSs and osteoblasts; (B) regulation of ECM degradation; (C) regulation of macrophage phenotypic transformation; (D) modulation of skeletal muscle and adipose tissues. Ubiquitination targeting drugs for OA treatment are also listed. Depending on the high efficiency of ubiquitination and deubiquitination, understanding OA-related ubiquitination pathways can help design more efficient drugs to treat OA and provide more potential targets for clinical treatment. The Translational Potential of This Article. In this paper, the ubiquitination-related pathways in osteoarthritis (OA), including aging, apoptosis and autophagy in chondrocytes, osteoblasts, FLSs and macrophages were investigated. In particular, several ubiquitination-related targets are expected to be effective approaches for OA clinical treatment. In addition, in the process of OA occurrence and development, the complex relationship between the local joint area and other tissues including skeletal muscle and adipose tissue is also discussed. These myokines and adipokines from musculoskeletal tissues are all expected to become efficient targets for OA treatment apart from the joint itself. In addition, those myokines secreted by cardiovascular tissues would show potential therapeutic effects as well. What if altering the contents for these ubiquitination-related targets in the serum through exercise will provide a new idea for OA therapy or prevent OA from deteriorating continuously?

6-Gingerol improves lipid metabolism disorders in skeletal muscle by regulating AdipoR1/AMPK signaling pathway

BACKGROUND

To delve into the precise mechanisms by which 6-gingerol ameliorates lipid metabolism disorders in skeletal muscle.

METHODS

The level of triglycerides (TG) was used to evaluate lipid deposition. In skeletal muscle, transmission electron microscopy (TEM) was employed to observe mitochondrial morphology. Additionally, PCR was applied to detect mitochondrial biogenesis, and levels of malondialdehyde (MDA), catalase (CAT), glutathione, r-glutamyl cysteingl+glycine (GSH) and nicotinamide adenine dinucleotide (NADH) were measured to assess mitochondrial oxidative stress levels. In vivo, flow cytometry and immunofluorescence assays were conducted to quantify reactive oxygen species (ROS) and mitochondrial membrane potential (MMP). Furthermore, the Seahorse XF assays was utilized to assess mitochondrial respiratory capacity. Fluorescence confocal microscopy and molecular docking were applied to analyze the binding of 6-gingerol and adiponectin receptor 1 (AdipoR1). The expression of AdipoR1, AMPK, PGC-1α and SIRT1 were detected by Western Blot.

RESULTS

In vivo, 6-gingerol could reduce body weight in mice induced by a high-fat diet, enhance metabolic profiles in plasma, decrease lipid accumulation in skeletal muscle and liver, and elevate adiponectin levels. In skeletal muscle, it could restore mitochondrial morphology, boost mitochondrial copy number and biogenesis, and mitigate oxidative stress. In vitro, 6-gingerol may directly interact with AdipoR1 to upregulate the expression of downstream proteins p-AMPK, SIRT1, and PGC-1α, leading to a reduction in lipid deposition, a decrease in ROS production, an increase in mitochondrial membrane potential, and an enhancement of mitochondrial respiratory capacity in C2C12 myotubes.

CONCLUSION

6-Gingerol ameliorated lipid metabolism in skeletal muscle by regulating the AdipoR1/AMPK signaling pathway.

Two-Pronged Attack: Dual Activation of Fat Reduction Using Near-Infrared-Responsive Nanosandwich for Targeted Anti-Obesity Treatment

Excessive fat accumulation and chronic inflammation are two typical characteristics of obesity. AMP-activated protein kinase (AMPK), a master regulator of energy metabolism, is involved in adipogenesis, lipogenesis, and inflammation modulation in adipose tissue (AT). Thus, effective lipid reduction and anti-inflammation through AMPK regulation play vital roles in treating obesity. Herein, an anti-obesity nanosandwich is fabricated through attaching polymetformin (PolyMet) onto photothermal agent black phosphorus nanosheets (BP). PolyMet activates AMPK to inhibit adipogenesis, promote browning, and mitigate AT inflammation by decreasing macrophage infiltration, repolarizing macrophage phenotype, and downregulating pro-inflammatory cytokines. Additionally, BP induces lipolysis and apoptosis of adipocytes and macrophages through a photothermal effect. By further functionalization using hyaluronic acid (HA) and MMP2 substrate-linking P3 peptide-modified HA (P3-HA), an enhanced anti-obesity effect is obtained by dual-targeting of P3 and HA, and HA-mediated CD44 poly-clustering after MMP2 cleavage. Upon laser irradiation, the designed nanosandwich (P3-HA/PM@BP) effectively inhibits obesity development in obese mice, increases M2/M1 ratio in AT, reduces the serum levels of cholesterol/triglyceride and improves insulin sensitivity, exhibiting promising research potential to facilitate the clinical development of modern anti-obesity therapies.

Development of a non-invasive bioassay for adiponectin target engagement in mice

Adiponectin-based therapeutic strategies are promising for managing metabolic diseases and reducing inflammation, prompting the development of adiponectin receptor agonists. However, monitoring their pharmacodynamic actions in clinical applications is challenging. This study aimed to identify peripheral biomarkers to monitor adiponectin actions using ALY688, an adiponectin receptor agonist peptide. RNA sequencing analysis of whole blood identified a cluster of genes that were significantly increased in the ALY688-treated group compared to the control. This gene cluster was validated by qPCR and further confirmed in human peripheral blood mononuclear cells treated with ALY688 ex vivo. We also confirmed a functional outcome of ALY688 action in mice as our study also demonstrated the anti-inflammatory effect of ALY688 in a sublethal LPS mouse model. In summary, a newly identified gene cluster signature is suitable for assessing the pharmacodynamic action of adiponectin or its mimetics in blood samples.

The role of AdipoQ on proliferation, apoptosis, and hormone Secretion in chicken primary adenohypophysis cells

Adiponectin (AdipoQ), an adipokine secreted by adipocytes, has been reported to exist widely in various cell types and tissues, including the adenohypophysis of chickens. However, the molecular mechanism by which AdipoQ regulates the function of chicken adenohypophysis remains elusive. In this study, we investigated the effects of AdipoQ on proliferation, apoptosis, secretion of related hormones (FSH, LH, TSH, GH, PRL and ACTH) and expression of related genes (FSHβ, LHβ, GnRHR, TSHβ, GH, PRL and ACTH) in primary adenohypophysis cells of chickens by using real-time fluorescent quantitative PCR (RT-qPCR), cell counting kit-8 (CCK-8), flow cytometry, enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) assays. Our results showed that AdipoQ promoted the proliferation of chicken primary adenohypophysis cells, up-regulated the mRNA expression of proliferation-related genes CDK1, PCNA, CCND1 and P21 (P < 0.05), as well as the increased protein expression of CDK1 and PCNA (P < 0.05). Furthermore, AdipoQ inhibited apoptosis of chicken primary adenohypophysis cells, resulting in down-regulation of pro-apoptotic genes Caspase3, Fas, and FasL mRNA expression, and decreased Caspase3 protein expression (P < 0.05). Moreover, there was an up-regulation of anti-apoptotic gene Bcl2 mRNA and protein expression (P < 0.05). Additionally, AdipoQ suppressed the secretion of FSH, LH, TSH, GH, PRL, and ACTH (P < 0.05), as well as the mRNA expression levels of related genes (P < 0.05). Treatment with AdipoRon (a synthetic substitute for AdipoQ) and co-treatment with RNA interference targeting AdipoQ receptors 1/2 (AdipoR1/2) had no effect on the secretion of FSH, LH, TSH, GH, PRL, and ACTH, as well as the mRNA expression levels of the related genes. This suggests that AdipoQ's regulation of hormone secretion and related gene expression is mediated by the AdipoR1/2 signaling axis. Importantly, we further demonstrated that the mechanism of AdipoQ on FSH, LH, TSH and GH secretion is realized through AMPK signaling pathway. In conclusion, we have revealed, for the first time the molecular mechanism by which AdipoQ regulates hormone secretion in chicken primary adenohypophysis cells.

Exercise-promoted adiponectin secretion activates autolysosomes to protect the liver of ApoE-/- mice from a high-fat diet

Fat is a "double-edged sword": while it is a necessary substance for the body, the long-term intake of excessive fat will cause obesity, with the liver subjected to lipotoxicity as it accumulates. It will then continue to deteriorate, eventually leading to liver failure, which is a negative impact of high-fat food intake. Research has shown that exercise can reverse the side effects of a chronic high-fat diet and help the body to mitigate the harmful effects of lipotoxicity. In our study, it was found that moderate-intensity cardio-training (MICT) and high-intensity interval exercise (HIIT) effectively protected the livers of high-fat diet (HFD) ApoE-/- mice against lipotoxicity. Previous results demonstrated that 12 weeks of HFD resulted in a significant elevation of CD36 in the livers of C57BL/6J mice, while knockdown of CD36 did not reduce the accumulation of fat in the liver. Therefore, we used ApoE-/- mice as experimental subjects. Although HFD caused the development of hyperlipidemia and atherosclerosis, it is interesting to note that, due to the knockdown of ApoE, the livers of ApoE-/- mice in the non-exercise group did not show significant lipid deposition; however, after 12 weeks of MICT and HIIT, the livers of ApoE-/- mice showed significant lipid deposition. After we analyzed the lipid metabolism in their livers, we found that this was caused by the promotion of transport of peripheral fat into the liver due to exercise. Moreover, 12 weeks of exercise effectively reduced atherosclerosis, and the livers of ApoE-/- mice in the exercise group were not damaged by lipotoxicity. The results showed that a 12-week exercise treatment activated AMPK in the livers of HFD ApoE-/- mice through the APN-AdipoR1 signaling pathway, improved hepatic lipid metabolism disorders, and promoted the nuclear translocation of TFEB to enhance autophagic-lysosomal lipid scavenging. After the peripheral lipid is input into the liver due to exercise, the energy generated through gluconeogenesis can be used to replenish the energy consumed by exercise and maintain the normal operation of various functions in the liver, based on which the high autophagic flux in the liver can be maintained and the lipid clearance rate can be enhanced to protect the liver from lipotoxicity.

Targeting the Epigenetic Marks in Type 2 Diabetes Mellitus: Will Epigenetic Therapy Be a Valuable Adjunct to Pharmacotherapy?

Although genetic, environmental, and lifestyle factors largely contribute to type 2 diabetes mellitus (T2DM) risk, the role of epigenetics in its pathogenesis is now well established. The epigenetic mechanisms in T2DM mainly consist of DNA methylation, histone modifications and regulation by noncoding RNAs (ncRNAs). For instance, DNA methylation at CpG islands in the promoter regions of specific genes encoding insulin signaling and glucose metabolism suppresses these genes. Modulating the enzyme mediators of these epigenetic marks aims to restore standard gene expression patterns and improve glycemic control. In targeting these epigenetic marks, using epigenetic drugs such as DNA methyltransferase (DNAMT), histone deacetylase (HDAC) and histone acetyltransferase (HAT) inhibitors has led to variable success in humans and experimental murine models. Specifically, the United States' Food and Drug Administration (US FDA) has approved DNAMT inhibitors like 5-azacytidine and 5-aza-2'-deoxycytidine for use in diabetic retinopathy: a T2DM microvascular complication. These DNAMT inhibitors block the genes for methylation of mitochondrial superoxide dismutase 2 (SOD2) and matrix metallopeptidase 9 (MMP-9): the epigenetic marks in diabetic retinopathy. Traditional pharmacotherapy with metformin also have epigenetic effects in T2DM and positively alter disease outcomes when combined with epigenetic drugs like DNAMT and HDAC inhibitors, raising the prospect of using epigenetic therapy as a valuable adjunct to pharmacotherapy. However, introducing small interfering RNAs (siRNAs) in cells to silence specific target genes remains in the exploratory phase. Future research should focus on regulating gene expression in T2DM using long noncoding RNA (lncRNA) molecules, another type of ncRNA. This review discusses the epigenetics of T2DM and that of its macro- and microvascular complications, and the potential benefits of combining epigenetic therapy with pharmacotherapy for optimal results.

Endocrine gland size is proportional to its target tissue size

Endocrine glands secrete hormones into the circulation to target distant tissues and regulate their functions. The qualitative relationship between hormone-secreting organs and their target tissues is well established, but a quantitative approach is currently limited. Quantification is important, as it could allow us to study the endocrine system using engineering concepts of optimality and tradeoffs. In this study, we collected literature data on 24 human hormones secreted from dedicated endocrine cells. We find that the number of endocrine cells secreting a hormone is proportional to the number of its target cells. A single endocrine cell serves approximately 2,000 target cells, a relationship that spans 6 orders of magnitude of cell numbers. This suggests an economic principle of cells working near their maximal capacity, and glands that are no bigger than they need to be.

Predictive etiological classification of acute ischemic stroke through interpretable machine learning algorithms: a multicenter, prospective cohort study

BACKGROUND

The prognosis, recurrence rates, and secondary prevention strategies varied significantly among different subtypes of acute ischemic stroke (AIS). Machine learning (ML) techniques can uncover intricate, non-linear relationships within medical data, enabling the identification of factors associated with etiological classification. However, there is currently a lack of research utilizing ML algorithms for predicting AIS etiology.

OBJECTIVE

We aimed to use interpretable ML algorithms to develop AIS etiology prediction models, identify critical factors in etiology classification, and enhance existing clinical categorization.

METHODS

This study involved patients with the Third China National Stroke Registry (CNSR-III). Nine models, which included Natural Gradient Boosting (NGBoost), Categorical Boosting (CatBoost), Extreme Gradient Boosting (XGBoost), Random Forest (RF), Light Gradient Boosting Machine (LGBM), Gradient Boosting Decision Tree (GBDT), Adaptive Boosting (AdaBoost), Support Vector Machine (SVM), and logistic regression (LR), were employed to predict large artery atherosclerosis (LAA), small vessel occlusion (SVO), and cardioembolism (CE) using an 80:20 randomly split training and test set. We designed an SFS-XGB with 10-fold cross-validation for feature selection. The primary evaluation metrics for the models included the area under the receiver operating characteristic curve (AUC) for discrimination and the Brier score (or calibration plots) for calibration.

RESULTS

A total of 5,213 patients were included, comprising 2,471 (47.4%) with LAA, 2,153 (41.3%) with SVO, and 589 (11.3%) with CE. In both LAA and SVO models, the AUC values of the ML models were significantly higher than that of the LR model (P < 0.001). The optimal model for predicting SVO (AUC [RF model] = 0.932) outperformed the optimal LAA model (AUC [NGB model] = 0.917) and the optimal CE model (AUC [LGBM model] = 0.846). Each model displayed relatively satisfactory calibration. Further analysis showed that the optimal CE model could identify potential CE patients in the undetermined etiology (SUE) group, accounting for 1,900 out of 4,156 (45.7%).

CONCLUSIONS

The ML algorithm effectively classified patients with LAA, SVO, and CE, demonstrating superior classification performance compared to the LR model. The optimal ML model can identify potential CE patients among SUE patients. These newly identified predictive factors may complement the existing etiological classification system, enabling clinicians to promptly categorize stroke patients' etiology and initiate optimal strategies for secondary prevention.