López-Gambero AJ, Vargas A, Del Mar Fernández-Arjona M
… +10 more, Rubio L, de Ceglia M, Vera-Fernández C, Campillo-Calatayud A, Rivera P, Rodríguez de Fonseca F, Barrios V, Chowen JA, Argente J, Suárez J
BACKGROUND: The growth hormone (GH)/insulin-like growth factor (IGF-1) axis determines optimal growth and affects metabolism and energy homeostasis. Pregnancy-associated plasma protein-A2 (PAPPA2) regulates bioactive IGF...BACKGROUND: The growth hormone (GH)/insulin-like growth factor (IGF-1) axis determines optimal growth and affects metabolism and energy homeostasis. Pregnancy-associated plasma protein-A2 (PAPPA2) regulates bioactive IGF-1 availability and patients with PAPPA2 deficiency have impaired growth and glucose metabolism. This axis is altered in metabolic disturbances such as obesity and anorexia nervosa in a sex-specific manner, but the mechanisms involved are not completely understood. Here we evaluated how Pappa2 deficiency affects energy homeostasis, focusing on male and female differences. METHODS: Growth and energy homeostasis were determined in male and female Pappa2 mice and control Pappa2 littermates, as well as their response to recombinant human (rh)PAPPA2, rhIGF-1 and rhIBFBP5. Effects of a high-carbohydrate diet (HCHD) on glucose tolerance, fuel partitioning, de novo lipogenesis and energy homeostasis were determined. RESULTS: Pappa2 mice had reduced body weight, bone length and lipid deposition associated with higher energy expenditure and intake. Male Pappa2 mice had mild glucose intolerance, altered bone mineral properties and higher energy costs for locomotor activity possibly due to inefficient muscle mitochondrial activity; whereas female Pappa2 mice had enhanced fatty acid oxidation on a normal diet, but not on a HCHD. All Pappa2 mice had lower hepatic fat deposition associated with lower IGF-1 activity in the liver, while fatty acid metabolism dysregulation in adipose tissue was found only in females. CONCLUSION: These data reinforce the importance of the GH/IGF-1 axis in metabolic control and emphasize the relevance of its fine-tuned control by Pappa2. Moreover, the differences between sexes in metabolic imbalances underscore the relevance of sex-specific strategies for treatment of metabolic imbalances.
Podocyte injury is a major determinant of diabetic nephropathy (DN). Critical structural proteins such as synaptopodin play an important role in maintaining podocyte morphology and function. Herein, we uncover a protecti...Podocyte injury is a major determinant of diabetic nephropathy (DN). Critical structural proteins such as synaptopodin play an important role in maintaining podocyte morphology and function. Herein, we uncover a protective role of Flotillin-2 (Flot2), a lipid microdomain-associated protein, in the development of DN by maintaining the stability of synaptopodin. We found that Flot2 was downregulated in podocytes and its expression was correlated with glomerular filtration rate and proteinuria in patients with DN. Functionally, Flot2 is protective in DN as global and podocyte-specific Flot2 knockout (KO) worsened podocyte injury and aggravated the disease as demonstrated by increasing albuminuria, thickening of glomerular basement membrane, and expansion of mesangium matrix in diabetic mice. In contrast, podocyte-specific Flot2 overexpression ameliorated diabetes-induced renal dysfunction and pathology. Mechanistically, we found that Flot2 directly interacted with synaptopodin and protected synaptopodin from ubiquitin degradation via the K48-linked polyubiquitination mediated proteasome pathway. Thus, our findings demonstrate that Flot2 is protective in DN and exerts its protective role by stabilizing synaptopodin. Targeting Flot2 may be a potential therapeutic approach in DN.
Kasahara K, Ichikawa Y, Hironaka J
… +11 more, Shinozaki T, Okada H, Nakajima H, Ushigome E, Hamaguchi M, Kurogi K, Murata H, Tsuda E, Yoshida N, Ito M, Fukui M
BACKGROUND: The obesity criteria for Japanese population are defined based on a cross-sectional study conducted 30 years ago. We aimed to examine the validity of a BMI of 25 kg/m as a determinant of obesity in the Japane...BACKGROUND: The obesity criteria for Japanese population are defined based on a cross-sectional study conducted 30 years ago. We aimed to examine the validity of a BMI of 25 kg/m as a determinant of obesity in the Japanese population by assessing the association between BMI and the lifestyle-related diseases in a large and long-term cohort. METHODS: This cohort study included 162,136 individuals aged ≥40 years who participated in a medical health checkup program at Panasonic Corporation covering 166 operational sites from 2008 to 2023. The associations between BMI and the development of lifestyle-related diseases during the follow-up period were assessed using a multivariate Cox proportional hazards model. A restricted cubic spline function was applied to model the associations between BMI and disease risk. The BMI values associated with the doubling of HRs (compared with a reference BMI of 22 kg/m) were examined. FINDINGS: The average follow-up duration ranged from 6 to 8 years depending on the outcome. Restricted cubic spline curves showed BMI values (kg/m) associated with an HR of 2 (vs. 22 kg/m): 24.6 for diabetes, 26.8 for hypertension, 32.3 for hypertriglyceridemia, 26.4 for low high-density lipoprotein cholesterol, 25 for high low-density lipoprotein cholesterol, 30.8 for coronary artery disease, 32.0 for stroke, and 25 for CKD after adjusting for covariates. Similar results were observed in subgroup analyses stratified by gender and age. CONCLUSION: The appropriateness of the conventional BMI threshold of 25 kg/m in Japan warrants reconsideration.
Many innate and adaptive immune cells are resident in non-lymphoid tissues and do not participate in peripheral circulation. These tissue-resident immune cells not only rapidly recognize and respond to local infections o...Many innate and adaptive immune cells are resident in non-lymphoid tissues and do not participate in peripheral circulation. These tissue-resident immune cells not only rapidly recognize and respond to local infections or injuries but also contribute to the maintenance of tissue homeostasis and immune balance. Immune cell function is closely associated with their metabolic state. Recent studies reveal that tissue-resident immune cells undergo unique metabolic reprogramming to adapt to their specific tissue microenvironment. This metabolic adaptation is crucial for their long-term survival, differentiation, and function. In this review, we systematically elaborate on the metabolic characteristics and tissue-specific regulatory mechanisms of CD8 tissue-resident memory T cells (T) and tissue-resident macrophages (TRMφs). Based on an in-depth analysis of the critical role of immunometabolic pathways in infection, cancer, and autoimmune diseases, we further summarize therapeutic strategies targeting these metabolic pathways and discuss their efficacy, potential side effects, and the challenges facing clinical translation.
BACKGROUND: The pathogenesis of type 2 diabetes mellitus (T2DM) is closely related to skeletal muscle insulin resistance (IR). Currently, there is still a lack of relevant treatments. Summary-data-based Mendelian randomi...BACKGROUND: The pathogenesis of type 2 diabetes mellitus (T2DM) is closely related to skeletal muscle insulin resistance (IR). Currently, there is still a lack of relevant treatments. Summary-data-based Mendelian randomization (SMR) is a vital tool for identifying druggable targets in skeletal muscle to develop T2DM treatments. METHODS: Potential causative genetic factors in skeletal muscle and blood causally associated with T2DM were identified by SMR analysis. Bayesian colocalisation were used to validate causality. Pleiotropic impact of drug targets was assessed using phenome-wide MR (Phe-MR). Then, targeted overexpression or knockdown of AEBP1 in mouse myoblast cell lines (C2C12) and human skeletal muscle cells (HSkMCs) further validated the functional phenotype. Protein docking, co-IP and SPR were used to demonstrate protein-protein interactions. RESULTS: Both European and Asian populations revealed that AEBP1 was significantly associated with T2DM and its glycemic profile in blood and skeletal muscle, and was identified as a risk factor. Co-localisation analyses suggest that AEBP1 and T2DM originate from the same genetic variants. Meanwhile, targeted AEBP1 therapy has no potential adverse effects. Furthermore, AEBP1 was significantly expressed in in vivo and in vitro IR models and was consistent with the SMR results. Overexpression of AEBP1 further impaired insulin signalling and glucose transport mechanisms, exacerbating skeletal muscle IR. Targeting AEBP1 knockdown reversed these changes. Protein interaction experiments revealed that PI3K (p110β) is a direct target protein for AEBP1 to exert molecular functions. CONCLUSION: Targeting AEBP1 therapy is expected to be a pivotal approach for the prevention and treatment of T2DM.
Cancer cells reprogram their metabolism to favor aerobic glycolysis and enhance carboxylic acid metabolism, supporting their energy needs and promoting tumor progression. This review explores the role of carboxylic acids...Cancer cells reprogram their metabolism to favor aerobic glycolysis and enhance carboxylic acid metabolism, supporting their energy needs and promoting tumor progression. This review explores the role of carboxylic acids, such as lactate, fatty acids, and amino acids, in cancer through four key pathways: (1) lactate-mediated tumor microenvironment acidification and immune suppression, (2) fatty acid metabolism driving tumorigenesis, (3) amino acid regulation of cancer cell survival, and (4) the crosstalk between these metabolic networks. These pathways contribute to immune evasion, proliferation, and drug resistance by modulating key enzymes, transporters, and signaling mechanisms. Despite their therapeutic potential, targeting carboxylic acid metabolism remains challenging owing to tumor adaptability and metabolic heterogeneity. Future research directions include the development of isoform-specific inhibitors, combination therapies, and precision medicine approaches based on metabolic profiling. Understanding these interconnected pathways may reveal new vulnerabilities for innovative cancer treatments.
BACKGROUND: Hypoparathyroidism (HypoPT) is characterized by low serum calcium due to insufficient parathyroid hormone (PTH). This manuscript builds upon the 2022 international HypoPT guidelines and three systematic revie...BACKGROUND: Hypoparathyroidism (HypoPT) is characterized by low serum calcium due to insufficient parathyroid hormone (PTH). This manuscript builds upon the 2022 international HypoPT guidelines and three systematic reviews, which have been further informed by updated narrative reviews and expert consensus. This paper presents current best practice consensus recommendations for the diagnosis and management of HypoPT. METHODS: An International Panel of Experts updated the previous systematic reviews (SR's), conducted narrative reviews, developed, and subsequently approved these best practice recommendations at the Parathyroid Summit, held as a pre-Endocrine Society meeting in May 2024 (Boston, USA). RESULTS: Diagnostic criteria for chronic HypoPT require hypocalcemia with inappropriately normal or low PTH levels. Conventional therapy is recommended as first line therapy and includes calcium supplementation, active vitamin D, correction of vitamin D inadequacy and correction of abnormalities in serum magnesium. Monitoring is required to achieve optimal serum calcium while avoiding hyperphosphatemia, hypercalciuria and declines in renal function. Assessment of HypoPT complications is required including skeletal health assessment in postmenopausal women and men over the age of 50 years. Specific strategies are provided for managing HypoPT during pregnancy and lactation as well as in children. PTH replacement with palopegteriparatide has been approved and is an important therapeutic option, especially when conventional therapy is inadequate or not tolerated. CONCLUSION: These best practice recommendations provide a framework for HypoPT diagnosis and management, emphasizing individualized care, role of DNA analysis in the diagnosis of nonsurgical HypoPT, and role of PTH or PTH analogue therapy as appropriate. They complement the 2022 international guidelines and incorporate updated therapeutic recommendations from the past 3 years including the positioning of the newly approved molecule palopegteriparatide based on recent clinical trial data and expert consensus.
This review investigates the emerging role of exosomal microRNAs (miRNAs) as pivotal mediators of bidirectional communication between the skeletal muscle and bone tissue, with significant implications for age-related mus...This review investigates the emerging role of exosomal microRNAs (miRNAs) as pivotal mediators of bidirectional communication between the skeletal muscle and bone tissue, with significant implications for age-related musculoskeletal disorders. In aging populations, sarcopenia often coexists with osteoporosis, forming osteosarcopenia, which markedly increases fracture risk, disability, and mortality. While traditional paradigms emphasize mechanical loading and endocrine pathways, emerging evidence has revealed that exosomes carrying bioactive miRNAs represent a novel class of paracrine factors in the muscle-bone axis. We examined how muscle-derived exosomal miRNAs (miR-34a and miR-27a-3p) influence bone metabolism, while bone-derived exosomal miRNAs (miR-486-5p) modulate muscle physiology. For each miRNA, we identified the target messenger RNAs (mRNAs) and signaling mechanisms. Importantly, exercise has emerged as a potent modulator of this crosstalk, altering exosomal miRNA profiles to promote anabolic outcomes in both tissues. This bidirectional communication contributes to osteosarcopenia pathophysiology, leading us to propose a novel "Exosomal miRNA Regulatory Network" for diagnosis and pathogenesis. Exosomal miRNAs show promise as early biomarkers for subclinical deterioration and therapeutic targets. However, methodological challenges in exosome isolation, incomplete characterization of miRNA networks, and aging complexity must be addressed before clinical implementation.
Cardiovascular diseases (CVDs), the leading cause of global mortality, are now understood to be profoundly influenced by the endocrine regulatory functions of the skeletal system. Emerging evidence suggests that osteocri...Cardiovascular diseases (CVDs), the leading cause of global mortality, are now understood to be profoundly influenced by the endocrine regulatory functions of the skeletal system. Emerging evidence suggests that osteocrine factors, including fibroblast growth factor-23 (FGF23), lipocalin-2 (LCN2), Dickkopf-1 (DKK1), myeloid-derived growth factor (MYDGF), osteocalcin (OCN), and sclerostin (SOST), establish bidirectional regulatory networks with the cardiovascular system, termed the "bone-heart axis". This axis regulates critical pathological processes, including mineral metabolism, vascular calcification, and myocardial energy homeostasis. Dysregulation of this crosstalk accelerates the progression of atherosclerosis (AS), heart failure (HF), and other CVDs. Therefore, current research necessitates a paradigm shift from univariate analyses to elucidating the spatiotemporal dynamics of interorgan communication, thereby facilitating the development of precision therapeutic strategies for integrated skeletal and cardiovascular protection.
Glycine is a conditionally essential amino acid obtained from food and synthesized in the body, primarily from l-serine. Glycine deficiency has been reported due to inadequate protein intake, malnutrition, late gestation...Glycine is a conditionally essential amino acid obtained from food and synthesized in the body, primarily from l-serine. Glycine deficiency has been reported due to inadequate protein intake, malnutrition, late gestation, diabetes, insulin resistance, and increased exposure to xenobiotics. Because of the close links in glycine and l-serine metabolism mediated by serine hydroxymethyltransferase (SHMT), decreased concentrations of both amino acids coincide in most glycine-deficient states. The consequence is a widespread impact on metabolism, including altered synthesis of glutathione, collagen, nucleotides, and one‑carbon units, impaired antioxidant defense, cytoprotection, conjugation, and neurotransmission and increased levels of homocysteine and deoxysphingolipids. It can, therefore, be assumed that, rather than glycine alone, its coadministration with l-serine is more appropriate in glycine-deficient conditions. Replacing a part of the glycine with l-serine should avoid (i) glycine flux through SHMT towards l-serine associated with the loss of methylenetetrahydrofolate, a substance essential for methylation reactions, and (ii) ammonia formation due to glycine flux through the glycine cleavage system. Unfortunately, studies comparing the effects of separate administration of glycine and its coadministration with l-serine do not exist. Well-controlled studies in subjects without glycine deficit are required to examine the potential benefits of high doses of glycine as a pharmaconutrient.
Mitochondrial dysfunction is a hallmark of aging and has been implicated in aging-related diseases. NIPSNAP1 and NIPSNAP2 are functionally redundant homologs involved in mitochondrial quality control, yet their roles in...Mitochondrial dysfunction is a hallmark of aging and has been implicated in aging-related diseases. NIPSNAP1 and NIPSNAP2 are functionally redundant homologs involved in mitochondrial quality control, yet their roles in healthy aging and longevity remain unclear. Here, we generated a Nipsnap1/2 double knockout (DKO) mouse line and examined its impacts on mitochondrial physiology and natural aging. We demonstrated that the loss of Nipsnap1/2 impaired mitochondrial function and enhanced glycolysis activity, but it did not affect mitophagy despite the significant accumulation of Parkin. Compared with wild-type mice, DKO mice exhibited reduced body weight, deteriorated muscle strength, and pronounced fragility at 24 months of age. Moreover, Nipsnap1/2 depletion exacerbates aging-associated fibrosis and inflammation in the heart, liver and kidney. RNA-seq revealed a pro-aging transcriptome reprogramming toward energy exhaustion in DKO mice, eventually leading to cachexia-like adverse metabolic remodeling. Our findings demonstrate an anti-aging role of NIPSNAP1/2 via the surveillance of mitochondrial health.
Ubiquitin-specific protease 48 (USP48) plays an important role in the regulation of DNA repair and immune signaling in health and diseases. Nonetheless, its implication in the development of diabetes-accelerated myocardi...Ubiquitin-specific protease 48 (USP48) plays an important role in the regulation of DNA repair and immune signaling in health and diseases. Nonetheless, its implication in the development of diabetes-accelerated myocardial ischemia/reperfusion (I/R) injury (MI/RI) has yet to be clarified. Diabetic mice were constructed by streptozotocin (STZ) injection, and MI/RI was then induced by coronary artery occlusion and reperfusion. H9c2 cells were exposed to high glucose (HG) for 24 h, followed by hypoxia/reoxygenation (H/R) for 4 and 2 h, respectively. USP48 protein and mRNA levels were downregulated in MI/RI mice or H/R-exposed cardiomyocytes, but were unexpectedly upregulated in diabetic mice following MI/RI and H9c2 cells exposed to HG and H/R. Cardiac-specific deficiency of USP48 worsened cardiac dysfunction, increased post-ischemic infarction size, promoted mitochondrial damage in myocardial cells, accelerated cardiomyocyte inflammation, oxidative stress, and apoptosis in diabetic mice. Conversely, such pathological conditions were ameliorated by cardiac-specific overexpression of USP48. Proteomics and experimental validation showed that USP48 stabilized and upregulated calponin 1 (CNN1) to confer cardioprotection, since silencing CNN1 minimized the benefits of USP48 in diabetes-aggravated cardiomyocyte injury. RNA sequencing and experimental data demonstrated that the USP48/CNN1 axis inhibited the release of CXC motif chemokine ligand 1 (CXCL1) and CXCL2 through inactivating the ERK1/2 pathway. Eventually, blockade of CXCL1/2 with specific antibodies protected against diabetes-exacerbated MI/RI, akin to USP48 overexpression. Together, these results highlight USP48 as a potential therapeutic target for managing diabetes-aggravated MI/RI by regulating the CNN1/ERK1/2/CXCL1/2 signaling pathway.
Katsarou A, Papadopoulos G, Moustakas II
… +13 more, Papadopetraki A, Moustogiannis A, Legaki AI, Giannousi E, Agrogiannis G, Pantelis P, Veroutis D, Evangelou K, Kotsinas A, Gorgoulis VG, Philippou A, Koutsilieris M, Chatzigeorgiou A
BACKGROUND: The present study aims at deciphering the individual or combined benefits of aerobic exercise and dietary restriction on liver senescence, a state characterized by cell cycle arrest and simultaneous resistanc...BACKGROUND: The present study aims at deciphering the individual or combined benefits of aerobic exercise and dietary restriction on liver senescence, a state characterized by cell cycle arrest and simultaneous resistance to apoptosis, which is considered an established hallmark of metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: C57BL6 mice were subjected to a normal diet (ND) for 20 weeks or a high-fat diet (HFD) supplemented with 5 % High-fructose Corn Syrup (HFCS) for 12 weeks, followed by eight-week interventions, including dietary restriction (DR), aerobic exercise (EX), a combination of both (DREX) or continuation of a HFD-HFCS diet without intervention. Biomarkers of senescence were analyzed in terms of their liver mRNA expression levels, while GL13 and p21 immunohistochemical stainings were conducted to examine the levels of senescence-associated lipofuscin and p21 respectively, to finally investigate their relationship with the grade of hepatic steatosis and fibrosis observed in the studied mice. RESULTS: DR and DREX groups exhibited significantly reduced features of obesity and MASLD-related hepatic steatosis and fibrosis, to a greater extent than the respective amelioration driven by aerobic exercise only in HFDEX animals. A statistically significant increase of mRNA expression was detected for cyclin-dependent kinase p21 in HFD livers as compared to ND, which was also reversed upon DR-inclusive interventions. Immunohistochemical stainings for GL13 and p21, as well as for p16 confirmed the aforementioned alterations of p21 at the tissular level while also revealed a p16 elevation in HFD livers which was reversed only upon DR/DREX. CONCLUSION: Liver senescence is responsive both to exercise and dietary restriction, but its amelioration in the context of MASLD is more robust upon DR-inclusive interventions.
BACKGROUND: Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive hepatic disorder characterized by its association with metabolic abnormalities, including obesity, hyperlipidemia, and type 2 diabetes...BACKGROUND: Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive hepatic disorder characterized by its association with metabolic abnormalities, including obesity, hyperlipidemia, and type 2 diabetes mellitus. Characterized by hepatic steatosis, inflammation, and fibrosis, MASH presents a significant global health challenge, with limited pharmacological options available. There is a critical need for novel therapeutic strategies targeting key molecular pathways involved in MASH pathogenesis. Combination therapy with these two drugs is expected to provide complementary preventive and therapeutic effects against MASH. METHODS: This study examined the therapeutic efficacy of a C-C chemokine receptor 2 (CCR2) inhibitor (RS-102895) in combination with a TGF-β type I receptor kinase inhibitor (vactosertib) in preclinical MASH models. Histological analysis, serum biomarker quantification, and gene expression profiling were performed to assess hepatic lipid accumulation, inflammation, fibrosis, and metabolic regulatory pathways. RESULTS: Combination therapy significantly improved histological parameters and reduced liver inflammation and fibrosis markers compared with monotherapy. Notably, it led to reductions in lipid accumulation and inflammatory cytokines, alongside the restoration of AMP-activated protein kinase (AMPK) activation, a key regulator of metabolic regulator. The study also identified the Rho-associated protein kinase 1 (ROCK1)/AMPK axis as a central mediator of MASH progression. CONCLUSIONS: These findings indicate that dual inhibition of CCR2 and TGF-β signaling pathways could serve as an effective therapeutic approach for MASH. By addressing lipid accumulation, inflammation, and fibrosis while promoting metabolic balance, this strategy holds promise for improved clinical applications in treating this complex disease.