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Cell Research Sep 2023The sarcomeric interaction of α-myosin heavy chain (α-MHC) with Titin is vital for cardiac structure and contraction. However, the mechanism regulating this...
The sarcomeric interaction of α-myosin heavy chain (α-MHC) with Titin is vital for cardiac structure and contraction. However, the mechanism regulating this interaction in normal and failing hearts remains unknown. Lactate is a crucial energy substrate of the heart. Here, we identify that α-MHC undergoes lactylation on lysine 1897 to regulate the interaction of α-MHC with Titin. We observed a reduction of α-MHC K1897 lactylation in mice and patients with heart failure. Loss of K1897 lactylation in α-MHC K1897R knock-in mice reduces α-MHC-Titin interaction and leads to impaired cardiac structure and function. Furthermore, we identified that p300 and Sirtuin 1 act as the acyltransferase and delactylase of α-MHC, respectively. Decreasing lactate production by chemical or genetic manipulation reduces α-MHC lactylation, impairs α-MHC-Titin interaction and worsens heart failure. By contrast, upregulation of the lactate concentration by administering sodium lactate or inhibiting the pivotal lactate transporter in cardiomyocytes can promote α-MHC K1897 lactylation and α-MHC-Titin interaction, thereby alleviating heart failure. In conclusion, α-MHC lactylation is dynamically regulated and an important determinant of overall cardiac structure and function. Excessive lactate efflux and consumption by cardiomyocytes may decrease the intracellular lactate level, which is the main cause of reduced α-MHC K1897 lactylation during myocardial injury. Our study reveals that cardiac metabolism directly modulates the sarcomeric structure and function through lactate-dependent modification of α-MHC.
Topics: Animals; Mice; Connectin; Myosin Heavy Chains; Heart Failure; Myocytes, Cardiac; Lactates
PubMed: 37443257
DOI: 10.1038/s41422-023-00844-w -
Autophagy Jan 2024Bevacizumab plays an important role in the first and second line treatment for metastatic colorectal cancer (CRC). And induction of hypoxia and the tumors response to it...
Tumor-derived lactate promotes resistance to bevacizumab treatment by facilitating autophagy enhancer protein RUBCNL expression through histone H3 lysine 18 lactylation (H3K18la) in colorectal cancer.
Bevacizumab plays an important role in the first and second line treatment for metastatic colorectal cancer (CRC). And induction of hypoxia and the tumors response to it plays an important role in determining the efficacy of antiangiogenic therapy while the connection between them remains unclear. Here, we found that lactate accumulated in the tumor environment of CRC and acted as substrates for histone lactylation, and this process was further induced by cellular enhanced glycolysis in hypoxia. We determined that CRC patients resistant to bevacizumab treatment presented with elevated levels of histone lactylation and inhibition of histone lactylation efficiently suppressed CRC tumorigenesis, progression and survival in hypoxia. Histone lactylation promoted the transcription of RUBCNL/Pacer, facilitating autophagosome maturation through interacting with BECN1 (beclin 1) and mediating the recruitment and function of the class III phosphatidylinositol 3-kinase complex, which had a crucial role in hypoxic cancer cells proliferation and survival. Moreover, combining inhibition of histone lactylation and macroautophagy/autophagy with bevacizumab treatment demonstrated remarkable treatment efficacy in bevacizumab-resistance patients-derived pre-clinical models. These findings delivered a new exploration and important supplement of metabolic reprogramming-epigenetic regulation, and provided a new strategy for improving clinical efficacy of bevacizumab in CRC by inhibition of histone lactylation. 2-DG: 2-deoxy-D-glucose; BECN1: beclin 1; CQ: chloroquine; CRC: colorectal cancer; DMOG: dimethyloxalylglycine; H3K18la: histone H3 lysine 18 lactylation; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; Nala: sodium lactate; PDO: patient-derived orgnoid; PDX: patient-derived xenograft; RUBCNL/Pacer: rubicon like autophagy enhancer; SQSTM1/p62: sequestosome 1.
Topics: Humans; Autophagy; Beclin-1; Bevacizumab; Colorectal Neoplasms; Epigenesis, Genetic; Histones; Hypoxia; Lactic Acid; Lysine
PubMed: 37615625
DOI: 10.1080/15548627.2023.2249762 -
Nature Communications Sep 2022Lactate is a key metabolite produced from glycolytic metabolism of glucose molecules, yet it also serves as a primary carbon fuel source for many cell types. In the...
Lactate is a key metabolite produced from glycolytic metabolism of glucose molecules, yet it also serves as a primary carbon fuel source for many cell types. In the tumor-immune microenvironment, effect of lactate on cancer and immune cells can be highly complex and hard to decipher, which is further confounded by acidic protons, a co-product of glycolysis. Here we show that lactate is able to increase stemness of CD8 T cells and augments anti-tumor immunity. Subcutaneous administration of sodium lactate but not glucose to mice bearing transplanted MC38 tumors results in CD8 T cell-dependent tumor growth inhibition. Single cell transcriptomics analysis reveals increased proportion of stem-like TCF-1-expressing CD8 T cells among intra-tumoral CD3 cells, a phenotype validated by in vitro lactate treatment of T cells. Mechanistically, lactate inhibits histone deacetylase activity, which results in increased acetylation at H3K27 of the Tcf7 super enhancer locus, leading to increased Tcf7 gene expression. CD8 T cells in vitro pre-treated with lactate efficiently inhibit tumor growth upon adoptive transfer to tumor-bearing mice. Our results provide evidence for an intrinsic role of lactate in anti-tumor immunity independent of the pH-dependent effect of lactic acid, and might advance cancer immune therapy.
Topics: Animals; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Glycolysis; Lactic Acid; Mice; Neoplasms; Tumor Microenvironment
PubMed: 36068198
DOI: 10.1038/s41467-022-32521-8 -
European Journal of Applied Physiology Apr 2020The purpose of this paper is to review the physiological mechanisms determining eccrine sweat composition to assess the utility of sweat as a proxy for blood or as a... (Review)
Review
PURPOSE
The purpose of this paper is to review the physiological mechanisms determining eccrine sweat composition to assess the utility of sweat as a proxy for blood or as a potential biomarker of human health or nutritional/physiological status.
METHODS
This narrative review includes the major sweat electrolytes (sodium, chloride, and potassium), other micronutrients (e.g., calcium, magnesium, iron, copper, zinc, vitamins), metabolites (e.g., glucose, lactate, ammonia, urea, bicarbonate, amino acids, ethanol), and other compounds (e.g., cytokines and cortisol).
RESULTS
Ion membrane transport mechanisms for sodium and chloride are well established, but the mechanisms of secretion and/or reabsorption for most other sweat solutes are still equivocal. Correlations between sweat and blood have not been established for most constituents, with perhaps the exception of ethanol. With respect to sweat diagnostics, it is well accepted that elevated sweat sodium and chloride is a useful screening tool for cystic fibrosis. However, sweat electrolyte concentrations are not predictive of hydration status or sweating rate. Sweat metabolite concentrations are not a reliable biomarker for exercise intensity or other physiological stressors. To date, glucose, cytokine, and cortisol research is too limited to suggest that sweat is a useful surrogate for blood.
CONCLUSION
Final sweat composition is not only influenced by extracellular solute concentrations, but also mechanisms of secretion and/or reabsorption, sweat flow rate, byproducts of sweat gland metabolism, skin surface contamination, and sebum secretions, among other factors related to methodology. Future research that accounts for these confounding factors is needed to address the existing gaps in the literature.
Topics: Acclimatization; Eccrine Glands; Electrolytes; Humans; Micronutrients; Physical Conditioning, Human; Sodium Chloride, Dietary; Specimen Handling; Sweat; Sweating
PubMed: 32124007
DOI: 10.1007/s00421-020-04323-7 -
Rheumatology (Oxford, England) May 2017Hyperuricaemia is a common clinical condition that can be defined as a serum uric acid level >6.8 mg/dl (404 µmol/l). Gout, a recognized complication of hyperuricaemia,... (Review)
Review
Hyperuricaemia is a common clinical condition that can be defined as a serum uric acid level >6.8 mg/dl (404 µmol/l). Gout, a recognized complication of hyperuricaemia, is the most common inflammatory arthritis in adults. Drug-induced hyperuricaemia and gout present an emergent and increasingly prevalent problem in clinical practice. Diuretics are one of the most important causes of secondary hyperuricaemia. Drugs raise serum uric acid level by an increase of uric acid reabsorption and/or decrease in uric acid secretion. Several drugs may also increase uric acid production. In this review, drugs leading to hyperuricaemia are summarized with regard to their mechanism of action and clinical significance. Increased awareness of drugs that can induce hyperuricaemia and gout, and monitoring and prevention are key elements for reducing the morbidity related to drug-induced hyperuricaemia and gout.
Topics: Androgens; Antitubercular Agents; Aspirin; Carbohydrates; Cytotoxins; Diuretics; Gout; Humans; Hyperuricemia; Immunosuppressive Agents; Niacin; Sodium Lactate; Testosterone; Uric Acid
PubMed: 27498351
DOI: 10.1093/rheumatology/kew293 -
Frontiers in Physiology 2022Elevated circulating lactate has been associated with obesity and insulin resistance. The aim of the current study was to determine if lactate-induced lysine lactylation...
Elevated circulating lactate has been associated with obesity and insulin resistance. The aim of the current study was to determine if lactate-induced lysine lactylation (kla), a post-translational modification, was present in human skeletal muscle and related to insulin resistance. Fifteen lean (Body Mass Index: 22.1 ± 0.5 kg/m) and fourteen obese (40.6 ± 1.4 kg/m) adults underwent a muscle biopsy and 2-h oral glucose tolerance test. Skeletal muscle lactylation was increased in obese compared to lean females (19%, < 0.05) and associated with insulin resistance (r = 0.37, < 0.05) in the whole group. Skeletal muscle lactylation levels were significantly associated with markers of anaerobic metabolism (plasma lactate and skeletal muscle lactate dehydrogenase [LDH], < 0.05) and negatively associated with markers of oxidative metabolism (skeletal muscle cytochrome c oxidase subunit 4 and Complex I [pyruvate] OXPHOS capacity, < 0.05). Treatment of primary human skeletal muscle cells (HSkMC) with sodium lactate for 24 h increased protein lactylation and IRS-1 serine 636 phosphorylation in a similar dose-dependent manner ( < 0.05). Inhibition of glycolysis (with 2-deoxy-d-glucose) or LDH-A (with sodium oxamate or LDH-A siRNA) for 24 h reduced HSkMC lactylation which paralleled reductions in culture media lactate accumulation. This study identified the existence of a lactate-derived post-translational modification in human skeletal muscle and suggests skeletal muscle lactylation could provide additional insight into the regulation of skeletal muscle metabolism, including insulin resistance.
PubMed: 36111162
DOI: 10.3389/fphys.2022.951390 -
Cell Metabolism Nov 2016Elevated lactate dehydrogenase A (LDHA) expression is associated with poor outcome in tumor patients. Here we show that LDHA-associated lactic acid accumulation in...
Elevated lactate dehydrogenase A (LDHA) expression is associated with poor outcome in tumor patients. Here we show that LDHA-associated lactic acid accumulation in melanomas inhibits tumor surveillance by T and NK cells. In immunocompetent C57BL/6 mice, tumors with reduced lactic acid production (Ldha) developed significantly slower than control tumors and showed increased infiltration with IFN-γ-producing T and NK cells. However, in Rag2γc mice, lacking lymphocytes and NK cells, and in Ifng mice, Ldha and control cells formed tumors at similar rates. Pathophysiological concentrations of lactic acid prevented upregulation of nuclear factor of activated T cells (NFAT) in T and NK cells, resulting in diminished IFN-γ production. Database analyses revealed negative correlations between LDHA expression and T cell activation markers in human melanoma patients. Our results demonstrate that lactic acid is a potent inhibitor of function and survival of T and NK cells leading to tumor immune escape.
Topics: Animals; Apoptosis; CD8-Positive T-Lymphocytes; Cell Count; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cytokines; Glycolysis; Humans; Immunologic Surveillance; Interferon-gamma; Isoenzymes; Killer Cells, Natural; L-Lactate Dehydrogenase; Lactate Dehydrogenase 5; Lactic Acid; Male; Melanoma; Mice, Inbred C57BL; NFATC Transcription Factors; Phenotype; Sodium Lactate; T-Lymphocytes; Up-Regulation
PubMed: 27641098
DOI: 10.1016/j.cmet.2016.08.011 -
Journal of Neuroinflammation Dec 2022Brain lactate concentrations are enhanced in response to cerebral ischemia and promote the formation of reactive astrocytes, which are major components of the...
BACKGROUND
Brain lactate concentrations are enhanced in response to cerebral ischemia and promote the formation of reactive astrocytes, which are major components of the neuroinflammatory response and functional recovery, following cerebral ischemia. NDRG2 is upregulated during reactive astrocyte formation. However, its regulation and function are unclear. We studied the relationship between lactate and NDRG2 in astrocytes under conditions of ischemia or oxygen-glucose deprivation (OGD).
METHODS
We examined astrocytic NDRG2 expression after middle cerebral artery occlusion (MCAO) using western blot and immunofluorescence staining. Under hypoxia conditions, we added exogenous L-lactate sodium (lactate) to cultured primary astrocytes to explore the effects of lactate on the ubiquitination modification of NDRG2. We profiled the transcriptomic features of NDRG2 silencing in astrocytes after 8 h of OGD conditions as well as exogenous lactate treatment by performing RNA-seq. Finally, we evaluated the molecular mechanisms of NDRG2 in regulating TNFα under OGD conditions using western blot and immunohistochemistry.
RESULTS
Reactive astrocytes strongly expressed NDRG2 in a rat model of MCAO. We also showed that lactate stabilizes astrocytic NDRG2 by inhibiting its ubiquitination. NDRG2 inhibition in astrocytes increased inflammation and upregulated immune-associated genes and signaling pathways. NDRG2 knockdown induced TNFα expression and secretion via c-Jun phosphorylation.
CONCLUSIONS
We revealed that under OGD conditions, lactate plays an important anti-inflammatory role and inhibits TNFα expression by stabilizing NDRG2, which is beneficial for neurological functional recovery. NDRG2 may be a new therapeutic target for cerebral ischemia.
Topics: Animals; Rats; Astrocytes; Tumor Necrosis Factor-alpha; Lactic Acid; Glucose; Brain Ischemia; Oxygen; Infarction, Middle Cerebral Artery; Inflammation; Ubiquitination; Nerve Tissue Proteins
PubMed: 36572898
DOI: 10.1186/s12974-022-02678-6 -
PLoS Pathogens May 2023Senecavirus A (SVA)-induced porcine idiopathic vesicular disease has caused huge economic losses worldwide. Glucose metabolism in the host cell is essential for SVA...
Senecavirus A (SVA)-induced porcine idiopathic vesicular disease has caused huge economic losses worldwide. Glucose metabolism in the host cell is essential for SVA proliferation; however, the impact of the virus on glucose metabolism in host cells and the subsequent effects are still unknown. Here, glycolysis induced by SVA is shown to facilitate virus replication by promoting lactate production, which then attenuates the interaction between the mitochondrial antiviral-signaling protein (MAVS) and retinoic acid-inducible gene I (RIG-I). SVA induces glycolysis in PK-15 cells, as indicated by significantly increased expression of hexokinase 2 (HK2), 6-phosphofructokinase (PFKM), pyruvate kinase M (PKM), phosphoglycerate kinase 1 (PGK1), hypoxia-inducible factor-1 alpha (HIF-1α), and superoxide dismutase-2 (SOD2) in a dose-and replication-dependent manner, and enhanced lactate production, while reducing ATP generation. Overexpression of PKM, PGK1, HIF-1α, and PDK3 in PK-15 cells and high glucose concentrations promote SVA replication, while glycolytic inhibitors decrease it. Inhibition of RLR signaling allowed better replication of SVA by promoting lactate production to attenuate the interaction between MAVS and RIG-I, and regulatory effect of glycolysis on replication of SVA was mainly via RIG-I signaling. SVA infection in mice increased expression of PKM and PGK1 in tissues and serum yields of lactate. Mice treated with high glucose and administered sodium lactate showed elevated lactate levels and better SVA replication, as well as suppressed induction of RIG-I, interferon beta (IFNβ), IFNα, interferon-stimulated gene 15 (ISG15), and interleukin 6 (IL-6). The inhibitory effect on interferons was lower in mice administered sodium oxamate and low glucose compared to the high glucose, indicating that RLR signaling was inhibited by SVA infection through lactate in vitro and in vivo. These results provide a new perspective on the relationship between metabolism and innate immunity of the host in SVA infection, suggesting that glycolysis or lactate may be new targets against the virus.
Topics: Swine; Mice; Animals; Lactic Acid; Glycolysis; Virus Replication; Glucose
PubMed: 37126525
DOI: 10.1371/journal.ppat.1011371