AIMS:Ferroptosis shows promise as a cancer treatment due to lipid hydroperoxide accumulation in an iron-dependent manner. Isocitrate dehydrogenase 1 (IDH1) mutation is common in gliomas and D-2-hydroxyglutarate (D-2HG) sensitizes cancer cells to ferroptosis. However, the regulation of ferroptosis in IDH1 mutant gliomas remains unclear. We hypothesize that IDH1 mutations induce glioma ferroptosis by regulating iron metabolism and antioxidant systems through the heme-BACH axis. RESULTS:IDH1 mutation induces ferroptosis in astrocytes and glioma cells demonstrated by growth inhibition, mitochondrial damage, and lipid peroxidation. In IDH1-mutant gliomas, both Fe2+ and reactive oxygen species accumulate due to impaired heme biosynthesis and thus BACH activation-dependent transcriptional repression of iron homeostasis and antioxidant response-related genes. The heme analogs zinc and tin protoporphyrin IX (ZnPP and SnPP) function as competitive inhibitors to reduce heme-dependent degradation of BACH and to exacerbate ferroptosis, especially for IDH1 mutants at extremely low concentrations. Primary mouse astrocytes and human glioma cell lines were used to determine the effect of IDH1 mutation on ferroptosis, while orthotopic xenograft models were used to evaluate heme analog efficacy. The drug affinity responsive target stability assay was used to determine the interaction between heme and its analog and BACH. INNOVATION AND CONCLUSIONS:We discover that IDH1 mutation induces ferroptosis by activating the heme-BACH axis. ZnPP, previously believed to function exclusively as a heme oxygenase-1 inhibitor, can competitively bind to BACH to exacerbate ferroptosis and potently suppress IDH1-mutant gliomas. This study reveals a novel metabolic mechanism for inducing ferroptosis and provides a potential therapeutic target for IDH-mutant gliomas. Paraffin-embedded human glioma samples were collected from Xijing Hospital, the First Affiliated Hospital of the Fourth Military Medical University (China) (project number: KY20233192-1). Antioxid. Redox Signal. 44, 145-163.

Genome-wide association studies (GWAS) face critical limitations in resolving noncoding variants with functional impacts. Here, we introduce a function-first prioritization strategy that integrates SNP-SELEX-derived transcription factor binding profiles with genetic epidemiology. Applied to type 2 diabetes in the UK Biobank (n = 480,000), this approach identified 305 risk SNPs—162 novel—with significantly enhanced heritability contribution, with 91 risk SNPs co-localizing at islet enhancers. CEBPB emerged as a master regulator. Focusing on a previously uncharacterized locus (rs2643219), we demonstrated allele-specific CEBPB binding at an intestinal enhancer regulating RASGRP1—a key effector for insulin-stimulated glucose uptake. CRISPR-mediated knockout of RASGRP1 in intestinal cells ablated GLUT4 translocation and impaired glucose homeostasis in mice. Trans-ethnic validation in a Chinese cohort (n = 1718) confirmed rs2643219's clinical relevance (OR = 1.30; P = 0.023). Our strategy bridges functional genomics with pathophysiological mechanisms, establishing a blueprint for complex disease variant prioritization.

Hepatocyte damage is the initial factor in liver injury. De novo expression of inositol 1,4,5-triphosphate receptor type 3 (ITPR3) typically occurs in hepatocellular carcinoma and may contribute to its pathogenesis. However, the role of de novo expression of ITPR3 by hepatocytes in the pathological processes of liver fibrosis remains unclear. Expression analyses of ITPR3 in hepatocytes were combined with an evaluation Ca2+/nuclear factor-κB (NF-κB)/leukocyte cell-derived chemotaxin 2 (LECT2) pathway and characterization of the effect of ITPR3 expression on hepatocytes damage. The effect of ITPR3 expression on liver fibrosis were evaluated in mice. ITPR3 expression was significantly increased in fibrotic mice livers and in hepatocytes induced by carbon tetrachloride (CCl4), correlating with hepatocytes apoptosis. Data from treatment with ITPR3 siRNA and an NF-κB inhibitor demonstrated that excessive Ca2+ release mediated by ITPR3 activated NF-κB, which in turn initiated LECT2 expression and induced hepatocytes apoptosis, leading to hepatic stellate cell activation-mediated liver fibrosis. These results demonstrate that de novo expression of ITPR3 may play an essential role in hepatocytes damage and liver fibrosis via Ca2+/NF-κB/LECT2 pathway. Suppression of ITPR3 may represent a novel strategy for attenuating hepatocyte damage and liver fibrosis.

Microglial hyperactivation-induced neuroinflammation is a central driver of neurological dysfunction after traumatic brain injury (TBI). Metabolic reprogramming is essential for microglial activation, but the specific metabolic alterations following TBI and their causal relationship with activation remain poorly defined. This study investigated the role and underlying mechanisms of glutamate-ammonia ligase (GLUL) in regulating microglial activation after TBI. A murine TBI model was established using a controlled cortical impact device, and brain injury severity, neuroinflammation, and behavioral outcomes were compared between wild-type and microglia-specific GLUL knockout mice. The inflammatory cytokine expression and amino acid metabolic fluxes assessed in GLUL-deficient microglia during activation in vivo and in vitro. Results showed that post-TBI microglia downregulate the GLUL expression, redirecting glutamate metabolism toward the pro-inflammatory arginine-citrulline cycle. This metabolic shift exacerbated microglial hyperactivation and aggravated neurological dysfunction following TBI. Conversely, inhibition of arginine-citrulline cycle attenuated microglial activation and suppressed pro-inflammatory cytokine release. Collectively, these findings identify a novel pathological mechanism linking metabolic alterations to microglial activation after TBI and suggest a metabolism-targeted strategy for anti-inflammatory therapy.

BRAFV600E mutant melanomas treated with BRAF inhibitor (BRAFi) and MEK inhibitor (MEKi) almost invariably develop drug resistance, accompanied by restored glucose metabolism. How resumed glycolysis controls acquired resistance remains unknown. Here, we identify that lysine-specific demethylase 1 (LSD1) lactylation, induced by re-accumulated lactate in both human and murine BRAFi/MEKi-resistant melanoma cells, selectively drives survival via epigenetic reprogramming. Mechanistically, lactylation of LSD1 promotes its interaction with Fos-related antigen 1 (FosL1), preventing its degradation by E3 ligase tripartite-motif-containing protein 21 (TRIM21) and selectively enhancing its genomic enrichment. We further demonstrate that lactylated LSD1 co-directs gene transcription with FosL1 to repress ferroptosis via interfering with transferrin receptor protein 1 (TFRC)-mediated iron uptake. LSD1 inhibition activates ferroptosis, resulting in drastic regression of drug-resistant murine melanoma when combined with immunotherapy. Our results highlight a crucial role of metabolic rewiring-induced epigenetic reprogramming as a bypass resistance mechanism in BRAFi/MEKi-resistant melanoma, providing a therapeutically actionable strategy to overcome resistance to targeted therapy and immunotherapy.

BACKGROUND:Microglial overactivation-driven neuroinflammation exacerbates secondary damage after spinal cord injury (SCI), but the role of mitochondrial iron metabolism in this process is not well understood. This study investigates the function of the mitochondrial iron transporter solute carrier family 25 member 28 (SLC25A28) in post-SCI neuroinflammation. METHODS:Microglia-specific SLC25A28 knockout (A28-MGKO) mice were generated by crossing SLC25A28flox/flox mice with Cx3cr1-CreERT2 mice and subjected to clip-compression spinal cord injury (SCI) at the T9 level. Motor recovery was evaluated using the Basso Mouse Scale (BMS), while histological and biochemical assessments including hematoxylin-eosin and Nissl staining, Iba1 immunohistochemistry, Evans blue permeability, and tissue water content were performed to evaluate lesion severity, neuronal survival, microglial activation, and blood-spinal cord barrier integrity. In vitro, primary microglia isolated from A28-MGKO mice and BV2 cells with SLC25A28 overexpression were used to investigate mitochondrial iron homeostasis, heme biosynthesis, and NOX2-mediated oxidative stress. Mitochondrial iron content was quantified using a ferrozine-based assay and Mito-FerroGreen staining, while ROS production, cytokine release, and inflammatory signaling were analyzed by fluorescence imaging, ELISA, and Western blotting under pharmacological modulation of heme synthesis and NOX2 activity. RESULTS:We found that SLC25A28 deficiency reduced spinal cord edema, blood-spinal cord barrier disruption, and motor deficits. Mechanistically, SLC25A28 knockout suppressed mitochondrial iron accumulation, inhibited heme synthesis, and reduced NOX2-mediated oxidative stress. However, SLC25A28 overexpression enhanced mitochondrial iron overload and NOX2-driven inflammation, which could be reversed by pharmacological blockade of NOX2 or heme synthesis. Restoration of heme synthesis in A28-MGKO microglia attenuated the anti-inflammatory effects of SLC25A28 knockout. CONCLUSION:These findings demonstrate that microglial SLC25A28 regulates neuroinflammation and functional recovery after SCI by promoting mitochondrial iron-dependent heme synthesis and NOX2 activation. Targeting the SLC25A28-heme-NOX2 axis may provide a novel therapeutic approach for SCI.

Objective: Recognizing glomerular lesions is essential in diagnosing chronic kidney disease. However, deep learning faces challenges due to the lesion heterogeneity, superposition, progression, and tissue incompleteness, leading to uncertainty in model predictions. Therefore, it is crucial to analyze pathology-related predictive uncertainty in glomerular lesion recognition and unveil its relationship with pathological properties and its impact on model performance. Methods: This paper presents a novel framework for pathology-related predictive uncertainty analysis towards glomerular lesion recognition, including prototype learning based predictive uncertainty estimation, pathologycharacterized correlation analysis and weight-redistributed prediction rectification. The prototype learning based predictive uncertainty estimation includes deep prototyping, affinity embedding, and multi-dimensional uncertainty fusion. The pathology-characterized correlation analysis is the first to use expert-based and learning- based approach to construct the pathology-related characterization of lesions and tissues. The weightredistributed prediction rectification module performs reweighting- based lesion recognition. Results: To validate the performance, extensive experiments were conducted. Based on the Spearman and Pearson correlation analysis, the proposed framework enables more efficient correlation analysis, and strong correlation with pathology-related characterization can be achieved (c index > 0.6 and p < 0.01). Furthermore, the prediction rectification module demonstrated improved lesion recognition performance across most metrics, with enhancements of up to 6.36 %. Conclusion: The proposed predictive uncertainty analysis in glomerular lesion recognition offers a valuable approach for assessing computational pathology's predictive uncertainty from a pathology-related perspective. Significance: The paper provides a solution for pathology-related predictive uncertainty estimation in algorithm development and clinical practice.

IDH1/2 mutations are prevalent genetic alterations in gliomas that facilitate metabolic reprogramming and epigenetic modifications, which are essential for glioma progression. However, their exact contributions to tumorigenesis remain to be fully elucidated. Cellular senescence is a known precursor to tumorigenesis, and multiple oncogenes can initiate this senescence program. Our study demonstrated that the IDH1 mutation inhibits the proliferation of astrocytes and glioma cells, inducing cellular senescence through mechanisms involving DNA damage and increased production of reactive oxygen species (ROS). Notably, these effects were mitigated by the addition of exogenous glutamine. Within cells, glutamine synthetase (GS) serves as the sole enzyme responsible for glutamine synthesis. We found that D-2-hydroxyglutarate (D-2HG), an oncometabolite generated by mutant IDH enzymes, directly inhibits GS activity by binding to the glutamate site, substantially reducing endogenous glutamine production and exacerbating senescence in IDH1-mutant glioma cells. Additionally, in human glioma samples, a greater prevalence of GS-positive astrocytes was detected in IDH-mutant gliomas, likely providing adequate glutamine to sustain growth and mitigate senescence in these cells. Our findings suggest that D-2HG promotes senescence in IDH1-mutant glioma cells by inhibiting GS activity and that disrupting glutamine transport between astrocytes and glioma cells may constitute a promising therapeutic strategy for targeting IDH-mutant gliomas.

Hypertension is one of the leading causes of death due to target organ injury from cardiovascular disease. Although there are many treatments, only one-sixth of hypertensive patients effectively control their blood pressure. Therefore, further understanding the pathogenesis of hypertension is essential for the treatment of hypertension. Much research shows that immune cells play an important role in the pathogenesis of hypertension. Here, we discuss the roles of different immune cells in hypertension. Many immune cells participate in innate and adaptive immune responses, such as monocytes/macrophages, neutrophils, dendritic cells, NK cells, and B and T lymphocytes. Immune cells infiltrate the blood vessels, kidneys, and hearts and cause damage. The mechanism is that immune cells secrete cytokines such as interleukin, interferon, and tumor necrosis factor, which affect the inflammatory reaction, oxidative stress, and kidney sodium water retention, and finally aggravate or reduce the dysfunction, remodeling, and fibrosis of the blood vessel, kidney, and heart to participate in blood pressure regulation. This article reviews the research progress on immune cells and hypertension.

Objective To explore the effects of iron overload on neutrophil function and peritonitis, as well as the possible mechanisms. Methods C57BL/6 mice were randomly divided into a control group and an iron overload group (10 mice in each group). Acute peritonitis model was induced by intraperitoneal injection of E.coli. The iron deposition in liver and spleen was assessed using H&E staining and the iron level in neutrophils was quantified by colorimetric analysis. The proportion and morphology of neutrophils were evaluated by blood cell counting plate and MGG staining, and the cellular aging of neutrophils was determined by senescence-associated β-galactosidase (SA-β-Gal) staining. The protein expression levels of P16 in neutrophils was detected using Western blot analysis and the bactericidal function of neutrophils was detected by LB smears. The mitochondrial membrane potential and mitochondrial function of neutrophils were detected by JC-1 staining and ATP kit, respectively. Results Compared with the control group, mice in the iron overload group exhibited following effects, including significantly higher iron content in the liver and spleen, a shorter survival time, significantly reduced bactericidal ability of neutrophil with no significant differences in the quantity or morphology, aggravated aging in neutrophils (indicated by increased expression of P16 and a higher number of SA-β-Gal positive cells), and decreased mitochondrial membrane potential and ATP levels. Conclusion Iron overload aggravates peritonitis by reducing the bactericidal ability of neutrophils.

Purpose Parkinson's disease (PD) involves pathological alterations that include cortical impairments at levels of region and network. However, its microstructural abnormalities remain to be further elucidated via an appropriate diffusion neuroimaging approach. This study aimed to comprehensively demonstrate the microstructural patterns of PD as mapped by diffusion kurtosis imaging (DKI). Methods The microstructure of grey matter in both the PD group and the matched healthy control group was quantified by a DKI metric (mean kurtosis). The intergroup difference and classification performance of global microstructural complexity were analyzed in a voxelwise manner and via a machine learning approach, respectively. The patterns of information flows were explored in terms of structural connectivity, network covariance and modular connectivity. Results Patients with PD exhibited global microstructural impairments that served as an efficient diagnostic indicator. Disrupted structural connections between the striatum and cortices as well as between the thalamus and cortices were widely distributed in the PD group. Aberrant covariance of the striatocortical circuitry and thalamocortical circuitry was observed in patients with PD, who also showed disrupted modular connectivity within the striatum and thalamus as well as across structures of the cortex, striatum and thalamus. Conclusion These findings verified the potential clinical application of DKI for the exploration of microstructural patterns in PD, contributing complementary imaging features that offer a deeper insight into the neurodegenerative process.

Isocitrate dehydrogenase (IDH) mutations frequently occur in lower-grade gliomas and secondary glioblastomas. Mutant IDHs exhibit a gain-of-function activity, leading to the production of D-2-hydroxyglutarate (D-2HG) by reducing α-ketoglutarate (α-KG), a central player in metabolism and epigenetic modifications. However, the role of α-KG homeostasis in IDH-mutated gliomagenesis remains elusive. In this study, we found that low expression of oxoglutarate dehydrogenase (OGDH) was a common feature in IDH-mutated gliomas, as well as in astrocytes. This low expression of OGDH resulted in the accumulation of α-KG and promoted astrocyte maturation. However, IDH1 mutation significantly reduced α-KG levels and increased glutaminolysis and DNA/histone methylation in astrocytes. These metabolic and epigenetic alterations inhibited astrocyte maturation and led to cortical dysplasia in mice. Moreover, our results also indicated that reduced OGDH expression can promote the differentiation of glioma cells, while IDH1 mutations impeded the differentiation of glioma cells with low OGDH by reducing the accumulation of α-KG and increasing glutaminolysis. Finally, we found that l-glutamine increased α-KG levels and augmented the differentiation-promoting effects of AGI5198, an IDH1-mutant inhibitor, in IDH1-mutant glioma cells. Collectively, this study reveals that low OGDH expression is a crucial metabolic characteristic of IDH-mutant gliomas, providing a potential strategy for the treatment of IDH-mutant gliomas by targeting α-KG homeostasis.

Background:Increased inflammation contributes to pressure overload-induced myocardial remodeling. 17(R)-Resolvin D1 (17(R)-RvD1), a potent lipid mediator derived from docosahexaenoic acid, possesses anti-inflammatory and pro-resolving properties. However, the association between 17(R)-RvD1 and pressure overload-induced cardiac hypertrophy remains unclear.Methods:Transverse aortic constriction (TAC) surgery was performed to establish a cardiac hypertrophy model. C57BL/6J mice were randomly assigned to the Sham, TAC and TAC+17(R)-RvD1 groups. 17(R)-RvD1 was injected (2 μg/kg, i.p.) before TAC surgery and once every other day after surgery for 4 weeks. The same volume of saline was injected into the mice in both Sham group and TAC group. Then, cardiac function was evaluated and heart tissues were collected for biological analysis.Results:17(R)-RvD1 treatment attenuated TAC-induced increase in left ventricular diameter and decrease in left ventricular contractility, mitigated increased cardiomyocyte cross-sectional area, and downregulated the expression of hypertrophic genes. Besides, 17(R)-RvD1 attenuated myocardial fibrosis, as indicated by the decreased LV collagen volume and expression of fibrotic genes. In addition, 17(R)-RvD1 ameliorated the inflammatory response in cardiac tissue, as illustrated by the decreased infiltration of CD68+ macrophages and reduced production of pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6. 17(R)-RvD1 treatment significantly suppressed the activation of NLRP3 inflammasome after TAC surgery, which might be responsible for the attenuation of inflammation in cardiac tissue.Conclusion:17(R)-RvD1 attenuated pressure overload-induced cardiac hypertrophy and fibrosis, and the possible mechanism may be associated with the inhibition of NLRP3 inflammasome. 17(R)-RvD1 may serve as a potential drug for the treatment of cardiac hypertrophy.

Background: Metachondromatosis (MC) is a rare hereditary disease with multiple osteochondromatous exostoses at the hands or feet. PTPN11/SHP2 inactivating mutations were essential for the development of MC.However, the epigenetic target of PTPN11/SHP2 for the development of MC remains unknown.Methods: Microcomputed tomography, chondrocyte differentiation assay, RNA-Seq and Chip-Seq analysis were applied to achieve a better understanding of PTPN11/SHP2 in MC development.Findings: Here, we unexpectedly detected that heterozygous and homozygous Ezh2 inactivation produced MC-like lesion in mice. Further investigations revealed Ezh2 loss promoted proliferation but inhibited the differentiation of perichondrial mesenchymal progenitors, which was essential for circumferential cartilage growth and MC production. Mechanically, Ezh2 was found to be a critical target of Ptpn11/Shp2, which inactivation inhibited Ezh2 phosphorylation and promoted Ezh2 ubiquitination degradation, thus reducing the level of H3K27me3 on the promoter of Indian hedgehog (Ihh) and activating the expression of Ihh. Genetically, Ezh2 and Utx, an H3K27me3 demethylase, played contrasting roles during the processes of chondrocyte hypertrophy and endochondral ossification. Double knockout Ezh2/Utx mice and small molecule inhibitor experiments indicated suppression of Utx can prominently inhibit the Ihh expression, the production and growth of MC-like lesions by Ezh2 inactivation.Interpretation: EZH2 is histone lysine methyltransferase and suppresses gene transcription by establishment of H3K27me3 modification.The results revealed that EZH2 was a critical target of PTPN11/SHP2 and its inactivation was essential for the initiation of MC. Inhibition of Utx activity can ameliorate MC formation in Ezh2 deleted mice, thus providing new clues to treat the disease.Funding: The National Natural Science Foundation of China. State Key Laboratory of Cancer Biology, Fourth Military Medical University. Shaanxi Society Development Sci-Tech Research Project and Scientific and technological innovation team of Shaanxi Innovation Capability Support Plan.Declaration of Interest: The authors declare no conflict of interest.Ethical Approval: All animal experiments were reviewed and approved by the Committee on Animal Care and Use and Committee on the Ethics of Animal Experiments of Fourth Military Medical University (Xi’an, China). All procedures were followed the National Institutes of Health Guide for the Care and Use of Laboratory Animals.

Objective To construct the prokaryotic expression plasmid of human mitoferrin 2 (SLC25A28), and to express and purify the protein for preparing its rabbit polyclonal antibody. Methods The prokaryotic expression plasmid pET28a(+)-SLC25A28-His was constructed and transferred into E. coli BL21 (DE3), and induced with Isopropyl-β-D-thiogalactopyranoside (IPTG). The SLC25A28 protein was extracted in form of inclusion bodies, and was further purified by His-NTA column after dissolved in 8 mol/L urea. The anti-SLC25A28 polyclonal antibody was prepared by immunizing rabbits, and its specificity was determined by Western blot analysis. Results pET28a(+)-SLC25A28-His was constructed and SLC25A28 protein was successfully expressed in E. coli BL21 (DE3) with the purity up to 90%. The Western blot results indicated that anti-SLC25A28 polyclonal antibody was capable to recognize specifically the SLC25A28 protein in testis. Conclusion The human SLC25A28 is successfully expressed in E. Coli, and the rabbit polyclonal antibody specific to SLC25A28 is prepared.

Iron is essential for living organisms. Iron-containing proteins play a key role in cell function, while iron overload produces reactive oxygen species through electron transfer, resulting in DNA damage, oxidative stress, metabolic disorder and tissue as well as organ dysfunction. Liver is the main organ of iron storage and is related to regulating the metabolism, utilization and excretion of iron and maintaining iron homeostasis. Iron overload is common in patients with liver diseases, which is closely related to the occurrence and development of liver diseases.

Although haemoglobin is a known carrier of oxygen in erythrocytes that functions to transport oxygen over a long range, its physiological roles outside erythrocytes are largely elusive 1 , 2 . Here we found that chondrocytes produced massive amounts of haemoglobin to form eosin-positive bodies in their cytoplasm. The haemoglobin body (Hedy) is a membraneless condensate characterized by phase separation. Production of haemoglobin in chondrocytes is controlled by hypoxia and is dependent on KLF1 rather than the HIF1/2α pathway. Deletion of haemoglobin in chondrocytes leads to Hedy loss along with severe hypoxia, enhanced glycolysis and extensive cell death in the centre of cartilaginous tissue, which is attributed to the loss of the Hedy-controlled oxygen supply under hypoxic conditions. These results demonstrate an extra-erythrocyte role of haemoglobin in chondrocytes, and uncover a heretofore unrecognized mechanism in which chondrocytes survive a hypoxic environment through Hedy.

The microglia overactivation-induced neuroinflammation is a significant cause of the brain injury after intracerebral hemorrhage (ICH). Iron homeostasis is crucial for microglia activation, but the mechanism and causality still need further study. This study aimed to explore the roles and mechanism of the mitochondrial iron transporter SLC25A28 in microglia activation after ICH. Intrastriatal injection of autologous blood was used to establish ICH model, and the neuroinflammation, iron metabolism and brain injuries were assessed in wildtype or microglia-specific SLC25A28 knockout mice after ICH. Mitochondria iron levels and microglial function were determined in SLC25A28 overexpressed or deleted microglia. The extracellular acidification rate (ECAR), lactate production, and glycolytic enzyme levels were used to determine aerobic glycolysis. The results showed that ICH stimulated mitochondrial iron overload, and synchronously upregulated the SLC25A28 expression. In vitro, SLC25A28 overexpression increased mitochondrial iron levels in microglia. Interestingly, microglial SLC25A28 deficiency ameliorated neuroinflammation, brain edema, blood–brain barrier injury and ethological alterations in mice after ICH. Mechanically, SLC25A28 deficiency inhibited microglial activation by restricting the aerobic glycolysis. Moreover, zinc protoporphyrin could reduce SLC25A28 expression and mitigated brain injury. SLC25A28 plays crucial roles in mitochondrial iron homeostasis and microglia activation after ICH, and it might be a potential therapeutic target for ICH.

Background Perilipin 5 (Plin5) is well known to maintain the stability of intracellular lipid droplets (LDs) and regulate fatty acid metabolism in oxidative tissues. It is highly expressed in the heart, but its roles have yet to be fully elucidated. Methods Plin5-deficient mice and Plin5/leptin-double-knockout mice were produced, and their histological structures and myocardial functions were observed. Critical proteins related to fatty acid and glucose metabolism were measured in heart tissues, neonatal mouse cardiomyocytes and Plin5-overexpressing H9C2 cells. 2-NBDG was employed to detect glucose uptake. The mitochondria and lipid contents were observed by MitoTracker and BODIPY 493/503 staining in neonatal mouse cardiomyocytes. Results Plin5 deficiency impaired glucose utilization and caused insulin resistance in mouse cardiomyocytes, particularly in the presence of fatty acids (FAs). Additionally, Plin5 deficiency increased the NADH content and elevated the expression of lactate dehydrogenase (LDHA) in cardiomyocytes, which resulted in increased lactate production. Moreover, when fatty acid oxidation was blocked by etomoxir or LDHA was inhibited by GSK2837808A in Plin5-deficient cardiomyocytes, glucose utilization was improved. Leptin-deficient mice exhibited myocardial hypertrophy, insulin resistance and altered substrate utilization, and Plin5 deficiency exacerbated myocardial hypertrophy in leptin-deficient mice. Conclusion Our results demonstrated that Plin5 plays a critical role in coordinating fatty acid and glucose oxidation in cardiomyocytes, providing a potential target for the treatment of metabolic disorders in the heart. Graphic abstract