RESUMO
Osteoarthritis (OA) is a worldwide joint disease, leading to the physical pain, stiffness, and even disability. Lactate dehydrogenase A (LDHA) is known as a lactylation mediator that can regulate histone lactylation of its target genes. However, the role of LDHA-mediated histone H3 lysine 18 lactylation (H3K18la) in OA progression is yet to be clarified. Our study aims at revealing the role and mechanism of LDHA-mediated histone lactylation in the glycolysis of chondrocytes. In this study, we determined at first that the H3K18la level was enhanced in OA. Energy metabolism such as glycolysis is often altered in OA progress. Therefore, we further explored the mechanism mediating glycolysis and thus promoting OA progress. Moreover, glycolysis was enhanced in LPS-induced OA cell model, as evidenced by the increased glucose consumption and lactate production. Furthermore, we silenced LDHA for loss-of-function assays. The results showed that knockdown of LDHA suppressed glycolysis of LPS-induced chondrocytes. In vivo animal study demonstrated that knockout of LDHA recovered cartilage injury of OA mice. Mechanistically, we uncovered that LDHA-mediated H3K18la in TPI1 promoter enhanced the transcription activity of TPI1. Mutation of K69 site was found to ameliorate LPS-induced glycolysis in OA cell model. In conclusion, our study reveals the role of LDHA-mediated H3K18la of TPI1 promoter in OA progress.
Assuntos
Condrócitos , Glicólise , Histonas , Osteoartrite , Osteoartrite/metabolismo , Osteoartrite/genética , Osteoartrite/patologia , Animais , Camundongos , Histonas/metabolismo , Humanos , Condrócitos/metabolismo , Modelos Animais de Doenças , Lactato Desidrogenase 5/metabolismo , Masculino , Regulação da Expressão Gênica , Camundongos Knockout , Regiões Promotoras Genéticas , Transcrição GênicaRESUMO
BACKGROUND: High levels of lactate are positively associated with prognosis and mortality in pulmonary hypertension (PH). Lactate dehydrogenase A (LDHA) is a key enzyme for the production of lactate. This study is undertaken to investigate the role and molecular mechanisms of lactate and LDHA in PH. METHODS: Lactate levels were measured by a lactate assay kit. LDHA expression and localization were detected by western blot and Immunofluorescence. Proliferation and migration were determined by CCK8, western blot, EdU assay and scratch-wound assay. The right heart catheterization and right heart ultrasound were measured to evaluate cardiopulmonary function. RESULTS: In vitro, we found that lactate promoted proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) in an LDHA-dependent manner. In vivo, we found that LDHA knockdown reduced lactate overaccumulation in the lungs of mice exposed to hypoxia. Furthermore, LDHA knockdown ameliorated hypoxia-induced vascular remodeling and right ventricular dysfunction. In addition, the activation of Akt signaling by hypoxia was suppressed by LDHA knockdown both in vivo and in vitro. The overexpression of Akt reversed the inhibitory effect of LDHA knockdown on proliferation in PASMCs under hypoxia. Finally, LDHA inhibitor attenuated vascular remodeling and right ventricular dysfunction in Sugen/hypoxia mouse PH model, Monocrotaline (MCT)-induced rat PH model and chronic hypoxia-induced mouse PH model. CONCLUSIONS: Thus, LDHA-mediated lactate production promotes pulmonary vascular remodeling in PH by activating Akt signaling pathway, suggesting the potential role of LDHA in regulating the metabolic reprogramming and vascular remodeling in PH.
Assuntos
Proliferação de Células , Hipertensão Pulmonar , L-Lactato Desidrogenase , Lactato Desidrogenase 5 , Ácido Láctico , Camundongos Endogâmicos C57BL , Artéria Pulmonar , Remodelação Vascular , Animais , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Lactato Desidrogenase 5/metabolismo , Masculino , Ácido Láctico/metabolismo , L-Lactato Desidrogenase/metabolismo , Artéria Pulmonar/patologia , Artéria Pulmonar/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Movimento Celular , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Hipóxia/complicações , Hipóxia/metabolismo , Transdução de Sinais , Técnicas de Silenciamento de Genes , Camundongos , Hipóxia Celular , Ratos Sprague-Dawley , Ratos , Humanos , Pulmão/patologia , Pulmão/irrigação sanguíneaRESUMO
Aim: Although lactate supplementation at the reperfusion stage of ischemic stroke has been shown to offer neuroprotection, whether the role of accumulated lactate at the ischemia phase is neuroprotection or not remains largely unknown. Thus, in this study, we aimed to investigate the roles and mechanisms of accumulated brain lactate at the ischemia stage in regulating brain injury of ischemic stroke. Methods and Results: Pharmacological inhibition of lactate production by either inhibiting LDHA or glycolysis markedly attenuated the mouse brain injury of ischemic stroke. In contrast, additional lactate supplement further aggravates brain injury, which may be closely related to the induction of neuronal death and A1 astrocytes. The contributing roles of increased lactate at the ischemic stage may be related to the promotive formation of protein lysine lactylation (Kla), while the post-treatment of lactate at the reperfusion stage did not influence the brain protein Kla levels with neuroprotection. Increased protein Kla levels were found mainly in neurons by the HPLC-MS/MS analysis and immunofluorescent staining. Then, pharmacological inhibition of lactate production or blocking the lactate shuttle to neurons showed markedly decreased protein Kla levels in the ischemic brains. Additionally, Ldha specific knockout in astrocytes (Aldh1l1 CreERT2; Ldha fl/fl mice, cKO) mice with MCAO were constructed and the results showed that the protein Kla level was decreased accompanied by a decrease in the volume of cerebral infarction in cKO mice compared to the control groups. Furthermore, blocking the protein Kla formation by inhibiting the writer p300 with its antagonist A-485 significantly alleviates neuronal death and glial activation of cerebral ischemia with a reduction in the protein Kla level, resulting in extending reperfusion window and improving functional recovery for ischemic stroke. Conclusion: Collectively, increased brain lactate derived from astrocytes aggravates ischemic brain injury by promoting the protein Kla formation, suggesting that inhibiting lactate production or the formation of protein Kla at the ischemia stage presents new therapeutic targets for the treatment of ischemic stroke.
Assuntos
Astrócitos , AVC Isquêmico , Ácido Láctico , Neurônios , Animais , Astrócitos/metabolismo , Camundongos , Ácido Láctico/metabolismo , Masculino , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Neurônios/metabolismo , Neurônios/patologia , Modelos Animais de Doenças , Camundongos Knockout , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos Endogâmicos C57BL , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Lesões Encefálicas/metabolismo , Lactato Desidrogenase 5/metabolismo , Fármacos Neuroprotetores/farmacologiaRESUMO
Breast cancer is the most prevalent malignancy and the most significant contributor to mortality in female oncology patients. Potassium Two Pore Domain Channel Subfamily K Member 1 (KCNK1) is differentially expressed in a variety of tumors, but the mechanism of its function in breast cancer is unknown. In this study, we found for the first time that KCNK1 was significantly up-regulated in human breast cancer and was correlated with poor prognosis in breast cancer patients. KCNK1 promoted breast cancer proliferation, invasion, and metastasis in vitro and vivo. Further studies unexpectedly revealed that KCNK1 increased the glycolysis and lactate production in breast cancer cells by binding to and activating lactate dehydrogenase A (LDHA), which promoted histones lysine lactylation to induce the expression of a series of downstream genes and LDHA itself. Notably, increased expression of LDHA served as a vicious positive feedback to reduce tumor cell stiffness and adhesion, which eventually resulted in the proliferation, invasion, and metastasis of breast cancer. In conclusion, our results suggest that KCNK1 may serve as a potential breast cancer biomarker, and deeper insight into the cancer-promoting mechanism of KCNK1 may uncover a novel therapeutic target for breast cancer treatment.
Assuntos
Neoplasias da Mama , Proliferação de Células , Histonas , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glicólise/genética , Histonas/metabolismo , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/genética , Lactato Desidrogenase 5/metabolismo , Lactato Desidrogenase 5/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Canais de Potássio de Domínios Poros em Tandem/genética , Prognóstico , Regulação para Cima/genéticaRESUMO
Cardiac fibrosis is a typical feature of cardiac pathological remodeling, which is associated with adverse clinical outcomes and has no effective therapy. Nicotine is an important risk factor for cardiac fibrosis, yet its underlying molecular mechanism remains poorly understood. This study aimed to identify its potential molecular mechanism in nicotine-induced cardiac fibrosis. Our results showed nicotine exposure led to the proliferation and transformation of cardiac fibroblasts (CFs) into myofibroblasts (MFs) by impairing autophagy flux. Through the use of drug affinity responsive target stability (DARTS) assay, cellular thermal shift assay (CETSA), and surface plasmon resonance (SPR) technology, it was discovered that nicotine directly increased the stability and protein levels of lactate dehydrogenase A (LDHA) by binding to it. Nicotine treatment impaired autophagy flux by regulating the AMPK/mTOR signaling pathway, impeding the nuclear translocation of transcription factor EB (TFEB), and reducing the activity of cathepsin B (CTSB). In vivo, nicotine treatment exacerbated cardiac fibrosis induced in spontaneously hypertensive rats (SHR) and worsened cardiac function. Interestingly, the absence of LDHA reversed these effects both in vitro and in vivo. Our study identified LDHA as a novel nicotine-binding protein that plays a crucial role in mediating cardiac fibrosis by blocking autophagy flux. The findings suggest that LDHA could potentially serve as a promising target for the treatment of cardiac fibrosis.
Assuntos
Autofagia , Fibrose , Nicotina , Animais , Autofagia/efeitos dos fármacos , Ratos , Masculino , Ratos Endogâmicos SHR , Transdução de Sinais/efeitos dos fármacos , Miocárdio/patologia , Miocárdio/metabolismo , Lactato Desidrogenase 5/metabolismo , Células Cultivadas , Humanos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Ratos Sprague-DawleyRESUMO
Podocytes are crucial for regulating glomerular permeability. They have foot processes that are integral to the renal filtration barrier. Understanding their energy metabolism could shed light on the pathogenesis of filtration barrier injury. Lactate has been increasingly recognized as more than a waste product and has emerged as a significant metabolic fuel and reserve. The recent identification of lactate transporters in podocytes, the expression of which is modulated by glucose levels and lactate, highlights lactate's relevance. The present study investigated the impact of lactate on podocyte respiratory efficiency and mitochondrial dynamics. We confirmed lactate oxidation in podocytes, suggesting its role in cellular energy production. Under conditions of glucose deprivation or lactate supplementation, a significant shift was seen toward oxidative phosphorylation, reflected by an increase in the oxygen consumption rate/extracellular acidification rate ratio. Notably, lactate dehydrogenase A (LDHA) and lactate dehydrogenase B (LDHB) isoforms, which are involved in lactate conversion to pyruvate, were detected in podocytes for the first time. The presence of lactate led to higher intracellular pyruvate levels, greater LDH activity, and higher LDHB expression. Furthermore, lactate exposure increased mitochondrial DNA-to-nuclear DNA ratios and resulted in upregulation of the mitochondrial biogenesis markers peroxisome proliferator-activated receptor coactivator-1α and transcription factor A mitochondrial, regardless of glucose availability. Changes in mitochondrial size and shape were observed in lactate-exposed podocytes. These findings suggest that lactate is a pivotal energy source for podocytes, especially during energy fluctuations. Understanding lactate's role in podocyte metabolism could offer insights into renal function and pathologies that involve podocyte injury.
Assuntos
L-Lactato Desidrogenase , Ácido Láctico , Dinâmica Mitocondrial , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Podócitos , Podócitos/metabolismo , Podócitos/patologia , Animais , Ratos , Ácido Láctico/metabolismo , L-Lactato Desidrogenase/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Glucose/metabolismo , Metabolismo Energético , Lactato Desidrogenase 5/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , DNA Mitocondrial/metabolismo , DNA Mitocondrial/genética , Consumo de Oxigênio , Células Cultivadas , Ácido Pirúvico/metabolismo , IsoenzimasRESUMO
Lactate dehydrogenase A (LDHA) primarily catalyzes the conversion between lactic acid and pyruvate, serving as a key enzyme in the aerobic glycolysis pathway of sugar in tumor cells. LDHA plays a crucial role in the occurrence, development, progression, invasion, metastasis, angiogenesis, and immune escape of tumors. Consequently, LDHA not only serves as a biomarker for tumor diagnosis and prognosis but also represents an ideal target for tumor therapy. Although LDHA inhibitors show great therapeutic potential, their development has proven to be challenging. In the development of LDHA inhibitors, the key active sites of LDHA are emphasized. Nevertheless, there is a relative lack of research on the amino acid residues around the active center of LDHA. Therefore, in this study, we investigated the amino acid residues around the active center of LDHA. Through structure comparison analysis, five key amino acid residues (Ala30, Met41, Lys131, Gln233, and Ala259) were identified. Subsequently, the effects of these five residues on the enzymatic properties of LDHA were investigated using site-directed mutagenesis. The results revealed that the catalytic activities of the five mutants varied to different degrees in both the reaction from lactic acid to pyruvate and pyruvate to lactic acid. Notably, the catalytic activities of LDHAM41G and LDHAK131I were improved, particularly in the case of LDHAK131I. The results of the molecular dynamics analysis of LDHAK131I explained the reasons for this phenomenon. Additionally, the optimum temperature of LDHAM41G and LDHAQ233M increased from 35 °C to 40 °C, whereas in the reverse reaction, the optimum temperature of LDHAM41G and LDHAK131I decreased from 70 °C to 60 °C. These findings indicate that Ala30, Met41, Lys131, Gln233, and Ala259 exert diverse effects on the catalytic activity and optimum temperature of LHDA. Therefore, these amino acid residues, in addition to the key catalytic site of the active center, play a crucial role. Considering these residues in the design and screening of LDHA inhibitors may lead to the development of more effective inhibitors.
Assuntos
Domínio Catalítico , Inibidores Enzimáticos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Aminoácidos/química , Aminoácidos/metabolismo , L-Lactato Desidrogenase/antagonistas & inibidores , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/química , Lactato Desidrogenase 5/metabolismo , Lactato Desidrogenase 5/antagonistas & inibidores , Lactato Desidrogenase 5/química , Ácido Pirúvico/metabolismo , Ácido Pirúvico/química , Mutagênese Sítio-Dirigida , Simulação de Dinâmica MolecularRESUMO
BACKGROUND: The initiation of fibroblast growth factor 1 (FGF1) expression coincident with the decrease of FGF2 expression is a well-documented event in prostate cancer (PCa) progression. Lactate dehydrogenase A (LDHA) and LDHB are essential metabolic products that promote tumor growth. However, the relationship between FGF1/FGF2 and LDHA/B-mediated glycolysis in PCa progression is not reported. Thus, we aimed to explore whether FGF1/2 could regulate LDHA and LDHB to promote glycolysis and explored the involved signaling pathway in PCa progression. METHODS: In vitro studies used RTâqPCR, Western blot, CCK-8 assays, and flow cytometry to analyze gene and protein expression, cell viability, apoptosis, and cell cycle in PCa cell lines. Glycolysis was assessed by measuring glucose consumption, lactate production, and extracellular acidification rate (ECAR). For in vivo studies, a xenograft mouse model of PCa was established and treated with an FGF pathway inhibitor, and tumor growth was monitored. RESULTS: FGF1, FGF2, and LDHA were expressed at high levels in PCa cells, while LDHB expression was low. FGF1/2 positively modulated LDHA and negatively modulated LDHB in PCa cells. The depletion of FGF1, FGF2, or LDHA reduced cell proliferation, induced cell cycle arrest, and inhibited glycolysis. LDHB overexpression showed similar inhibitory effect on PCa cells. Mechanistically, we found that FGF1/2 positively regulated STAT1 and STAT1 transcriptionally activated LDHA expression while suppressed LDHB expression. Furthermore, the treatment of an FGF pathway inhibitor suppressed PCa tumor growth in mice. CONCLUSION: The FGF pathway facilitates glycolysis by activating LDHA and suppressing LDHB in a STAT1-dependent manner in PCa.
Assuntos
Fatores de Crescimento de Fibroblastos , Glicólise , L-Lactato Desidrogenase , Neoplasias da Próstata , Fator de Transcrição STAT1 , Transdução de Sinais , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/genética , Humanos , Animais , L-Lactato Desidrogenase/metabolismo , Linhagem Celular Tumoral , Fator de Transcrição STAT1/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Camundongos Nus , Proliferação de Células , Camundongos , Regulação Neoplásica da Expressão Gênica , Fator 2 de Crescimento de Fibroblastos/metabolismo , Apoptose , Lactato Desidrogenase 5/metabolismo , IsoenzimasRESUMO
PURPOSE: Intrahepatic cholangiocarcinoma (iCCA) is a highly malignant and fatal liver tumor with increasing incidence worldwide. Lactate metabolism has been recently reported as a crucial contributor to tumor progression and immune regulation in the tumor microenvironment. However, it remains poorly identified about the biological functions of lactate metabolism in iCCA, which hinders the development of prognostic tools and therapeutic interventions. METHODS: The univariate Cox regression analysis and Boruta algorithm were utilized to identify key lactate metabolism-related genes (LMRGs), and a prognostic signature was constructed based on LMRG scores. Genomic variations and immune cell infiltration were evaluated in the high and low LMRG score groups. Finally, the biological functions of key LMRGs were verified with in vitro and in vivo experiments. RESULTS: Patients in the high LMRG score group exhibit a poor prognosis compared to those in the low LMRG score group, with a high frequency of TP53 and KRAS mutations. Moreover, the infiltration and function of NK cells were compromised in the high LMRG score group, consistent with the results from two independent single-cell RNA sequencing datasets and immunohistochemistry of tissue microarrays. Experimental data revealed that lactate dehydrogenase A (LDHA) knockdown inhibited proliferation and migration in iCCA cell lines and tumor growth in immunocompetent mice. CONCLUSION: Our study revealed the biological roles of LDHA in iCCA and developed a reliable lactate metabolism-related prognostic signature for iCCA, offering promising therapeutic targets for iCCA in the clinic.
Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Animais , Camundongos , Prognóstico , Colangiocarcinoma/genética , Lactato Desidrogenase 5 , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Lactatos , Microambiente Tumoral/genéticaRESUMO
Genotoxic therapy triggers reactive oxygen species (ROS) production and oxidative tissue injury. S-nitrosylation is a selective and reversible posttranslational modification of protein thiols by nitric oxide (NO), and 5,6,7,8-tetrahydrobiopterin (BH4) is an essential cofactor for NO synthesis. However, the mechanism by which BH4 affects protein S-nitrosylation and ROS generation has not been determined. Here, we showed that ionizing radiation disrupted the structural integrity of BH4 and downregulated GTP cyclohydrolase I (GCH1), which is the rate-limiting enzyme in BH4 biosynthesis, resulting in deficiency in overall protein S-nitrosylation. GCH1-mediated BH4 synthesis significantly reduced radiation-induced ROS production and fueled the global protein S-nitrosylation that was disrupted by radiation. Likewise, GCH1 overexpression or the administration of exogenous BH4 protected against radiation-induced oxidative injury in vitro and in vivo. Conditional pulmonary Gch1 knockout in mice (Gch1fl/fl; Sftpa1-Cre+/- mice) aggravated lung injury following irradiation, whereas Gch1 knock-in mice (Gch1lsl/lsl; Sftpa1-Cre+/- mice) exhibited attenuated radiation-induced pulmonary toxicity. Mechanistically, lactate dehydrogenase (LDHA) mediated ROS generation downstream of the BH4/NO axis, as determined by iodoacetyl tandem mass tag (iodoTMT)-based protein quantification. Notably, S-nitrosylation of LDHA at Cys163 and Cys293 was regulated by BH4 availability and could restrict ROS generation. The loss of S-nitrosylation in LDHA after irradiation increased radiosensitivity. Overall, the results of the present study showed that GCH1-mediated BH4 biosynthesis played a key role in the ROS cascade and radiosensitivity through LDHA S-nitrosylation, identifying novel therapeutic strategies for the treatment of radiation-induced lung injury.
Assuntos
Biopterinas , GTP Cicloidrolase , Lesão Pulmonar , Espécies Reativas de Oxigênio , Animais , Biopterinas/análogos & derivados , Biopterinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Lesão Pulmonar/metabolismo , Lesão Pulmonar/etiologia , GTP Cicloidrolase/metabolismo , GTP Cicloidrolase/genética , Humanos , Tolerância a Radiação/genética , Lactato Desidrogenase 5/metabolismo , Camundongos Knockout , Óxido Nítrico/metabolismo , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/genética , Processamento de Proteína Pós-Traducional , Radiação IonizanteRESUMO
Oligodendrocytes and astrocytes are metabolically coupled to neuronal compartments. Pyruvate and lactate can shuttle between glial cells and axons via monocarboxylate transporters. However, lactate can only be synthesized or used in metabolic reactions with the help of lactate dehydrogenase (LDH), a tetramer of LDHA and LDHB subunits in varying compositions. Here we show that mice with a cell type-specific disruption of both Ldha and Ldhb genes in oligodendrocytes lack a pathological phenotype that would be indicative of oligodendroglial dysfunctions or lack of axonal metabolic support. Indeed, when combining immunohistochemical, electron microscopical, and in situ hybridization analyses in adult mice, we found that the vast majority of mature oligodendrocytes lack detectable expression of LDH. Even in neurodegenerative disease models and in mice under metabolic stress LDH was not increased. In contrast, at early development and in the remyelinating brain, LDHA was readily detectable in immature oligodendrocytes. Interestingly, by immunoelectron microscopy LDHA was particularly enriched at gap junctions formed between adjacent astrocytes and at junctions between astrocytes and oligodendrocytes. Our data suggest that oligodendrocytes metabolize lactate during development and remyelination. In contrast, for metabolic support of axons mature oligodendrocytes may export their own glycolysis products as pyruvate rather than lactate. Lacking LDH, these oligodendrocytes can also "funnel" lactate through their "myelinic" channels between gap junction-coupled astrocytes and axons without metabolizing it. We suggest a working model, in which the unequal cellular distribution of LDH in white matter tracts facilitates a rapid and efficient transport of glycolysis products among glial and axonal compartments.
Assuntos
Axônios , Glicólise , L-Lactato Desidrogenase , Oligodendroglia , Animais , Oligodendroglia/metabolismo , Axônios/metabolismo , L-Lactato Desidrogenase/metabolismo , L-Lactato Desidrogenase/genética , Glicólise/fisiologia , Camundongos , Regulação para Baixo/fisiologia , Camundongos Endogâmicos C57BL , Lactato Desidrogenase 5/metabolismo , Astrócitos/metabolismo , Astrócitos/ultraestrutura , Camundongos Transgênicos , Isoenzimas/metabolismo , Isoenzimas/genética , Junções Comunicantes/metabolismo , Junções Comunicantes/ultraestrutura , Camundongos KnockoutRESUMO
Metabolic reprogramming, a hallmark of cancer, is closely associated with tumor development and progression. Changes in glycolysis play a crucial role in conferring radiation resistance to tumor cells. How radiation changes the glycolysis status of cancer cells is still unclear. Here we revealed the role of TAB182 in regulating glycolysis and lactate production in cellular response to ionizing radiation. Irradiation can significantly stimulate the production of TAB182 protein, and inhibiting TAB182 increases cellular radiosensitivity. Proteomic analysis indicated that TAB182 influences several vital biological processes, including multiple metabolic pathways. Knockdown of TAB182 results in decreased lactate production and increased pyruvate and ATP levels in cancer cells. Moreover, knocking down TAB182 reverses radiation-induced metabolic changes, such as radioresistant-related lactate production. TAB182 is necessary for activating LDHA transcription by affecting transcription factors SP1 and c-MYC; its knockdown attenuates the upregulation of LDHA by radiation, subsequently suppressing lactate production. Targeted suppression of TAB182 significantly enhances the sensitivity of murine xenograft tumors to radiotherapy. These findings advance our understanding of glycolytic metabolism regulation in response to ionizing radiation, which may offer significant implications for developing new strategies to overcome tumor radioresistance.
Assuntos
L-Lactato Desidrogenase , Proteômica , Humanos , Animais , Camundongos , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5/metabolismo , Linhagem Celular Tumoral , Glicólise , Lactatos , Tolerância a Radiação/genéticaRESUMO
SET domain bifurcated 1 (SETDB1), a pivotal histone lysine methyltransferase, is transported to the cytoplasm via a chromosome region maintenance 1 (CMR1)dependent pathway, contributing to nonhistone methylation. However, the function and underlying mechanism of cytoplasmic SETDB1 in breast cancer remain elusive. In the present study, immunohistochemistry revealed that elevated cytoplasmic SETDB1 was correlated with lymph node metastasis and more aggressive breast cancer subtypes. Functionally, wound healing and Transwell assays showed that cytoplasmic SETDB1 is key for cell migration and invasion, as well as induction of epithelialmesenchymal transition (EMT), which was reversed by leptomycin B (LMB, a CMR1 inhibitor) treatment. Furthermore, RNAseq and metabolite detection revealed that cytoplasmic SETDB1 was associated with metabolism pathway and elevated levels of metabolites involved in the Warburg effect, including glucose, pyruvate, lactate and ATP. Immunoblotting and reverse transcriptionquantitative PCR verified that elevation of cytoplasmic SETDB1 contributed to elevation of cMYC expression and subsequent upregulation of lactate dehydrogenase A (LDHA) expression. Notably, gain and lossoffunction approaches revealed that LDHA overexpression in T47D cells enhanced migration and invasion by inducing EMT, while its depletion in SETDB1overexpressing MCF7 cells reversed SETDB1induced migration and invasion, as well as the Warburg effect and EMT. In conclusion, subcellular localization of cytoplasmic SETDB1 may be a pivotal factor in breast cancer progression. The present study offers valuable insight into the novel functions and mechanisms of cytoplasmic SETDB1.
Assuntos
Neoplasias da Mama , Domínios PR-SET , Feminino , Humanos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Lactato Desidrogenase 5/genética , Lactato Desidrogenase 5/metabolismoRESUMO
Abundant macrophage infiltration and altered tumor metabolism are two key hallmarks of glioblastoma. By screening a cluster of metabolic small-molecule compounds, we show that inhibiting glioblastoma cell glycolysis impairs macrophage migration and lactate dehydrogenase inhibitor stiripentol emerges as the top hit. Combined profiling and functional studies demonstrate that lactate dehydrogenase A (LDHA)-directed extracellular signal-regulated kinase (ERK) pathway activates yes-associated protein 1 (YAP1)/ signal transducer and activator of transcription 3 (STAT3) transcriptional co-activators in glioblastoma cells to upregulate C-C motif chemokine ligand 2 (CCL2) and CCL7, which recruit macrophages into the tumor microenvironment. Reciprocally, infiltrating macrophages produce LDHA-containing extracellular vesicles to promote glioblastoma cell glycolysis, proliferation, and survival. Genetic and pharmacological inhibition of LDHA-mediated tumor-macrophage symbiosis markedly suppresses tumor progression and macrophage infiltration in glioblastoma mouse models. Analysis of tumor and plasma samples of glioblastoma patients confirms that LDHA and its downstream signals are potential biomarkers correlating positively with macrophage density. Thus, LDHA-mediated tumor-macrophage symbiosis provides therapeutic targets for glioblastoma.
Assuntos
Glioblastoma , Animais , Humanos , Camundongos , Glioblastoma/genética , L-Lactato Desidrogenase/genética , Lactato Desidrogenase 5 , Ácido Láctico , Simbiose , Microambiente TumoralRESUMO
As one of the key metabolic enzymes in the glycolytic pathway, lactate dehydrogenase A (LDHA) might be linked to tumor proliferation by driving the Warburg effect. Circular RNAs (circRNAs) are widely implicated in tumor progression. Here, we report that circTATDN3, a circular RNA that interacts with LDHA, plays a critical role in proliferation and energy metabolism in CRC. We found that circTATDN3 expression was increased in CRC cells and tumor tissues and that high circTATDN3 expression was positively associated with poor postoperative prognosis in CRC patients. Additionally, circTATDN3 promoted the proliferation of CRC cells in vivo and vitro. Mechanistically, circTATDN3 was shown to function as an adaptor molecule that enhances the binding of LDHA to FGFR1, leading to increased LDHA phosphorylation and consequently promoting the Warburg effect. Moreover, circTATDN3 increased the expression of LDHA by sponging miR-511-5p, which synergistically promoted CRC progression and the Warburg effect. In conclusion, circTATDN3 may be a target for the treatment of CRC.
Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , RNA Circular/genética , Linhagem Celular Tumoral , Lactato Desidrogenase 5/genética , Lactato Desidrogenase 5/metabolismo , Neoplasias Colorretais/patologia , Proliferação de Células , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação Neoplásica da Expressão GênicaRESUMO
Due to insufficient and defective vascularization, the tumor microenvironment is often nutrient-depleted. LDHA has been demonstrated to play a tumor-promoting role by facilitating the glycolytic process. However, whether and how LDHA regulates cell survival in the nutrient-deficient tumor microenvironment is still unclear. Here, we sought to investigate the role and mechanism of LDHA in regulating cell survival and proliferation under energy stress conditions. Our results showed that the aerobic glycolysis levels, cell survival and proliferation of cervical cancer cells decreased significantly after inhibition of LDHA under normal culture condition while LDHA deficiency greatly inhibited glucose starvation-induced ferroptosis and promoted cell proliferation and tumor formation under energy stress conditions. Mechanistic studies suggested that glucose metabolism shifted from aerobic glycolysis to mitochondrial OXPHOS under energy stress conditions and LDHA knockdown increased accumulation of pyruvate in the cytosol, which entered the mitochondria and upregulated the level of oxaloacetate by phosphoenolpyruvate carboxylase (PC). Importantly, the increase in oxaloacetate production after absence of LDHA remarkably activated AMP-activated protein kinase (AMPK), which increased mitochondrial biogenesis and mitophagy, promoted mitochondrial homeostasis, thereby decreasing ROS level. Moreover, repression of lipogenesis by activation of AMPK led to elevated levels of reduced nicotinamide adenine dinucleotide phosphate (NADPH), which effectively resisted ROS-induced cell ferroptosis and enhanced cell survival under energy stress conditions. These results suggested that LDHA played an opposing role in survival and proliferation of cervical cancer cells under energy stress conditions, and inhibition of LDHA may not be a suitable treatment strategy for cervical cancer.
Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Proteínas Quinases Ativadas por AMP , Lactato Desidrogenase 5 , Oxaloacetatos , Espécies Reativas de Oxigênio , Microambiente Tumoral , Neoplasias do Colo do Útero/genéticaRESUMO
Lactate dehydrogenase A (LDHA) serves as a key regulator of the Warburg Effect by catalyzing the conversion of pyruvate to lactate in the final step of glycolysis. Both the expression level and enzyme activity of LDHA are upregulated in cancers, however, the underlying mechanism remains incompletely understood. Here, we show that LDHA is post-translationally palmitoylated by ZDHHC9 at cysteine 163, which promotes its enzyme activity, lactate production, and reduces reactive oxygen species (ROS) generation. Replacement of endogenous LDHA with a palmitoylation-deficient mutant leads to reduced pancreatic cancer cell proliferation, increased T-cell infiltration, and limited tumor growth; it also affects pancreatic cancer cell response to chemotherapy. Moreover, LDHA palmitoylation is upregulated in gemcitabine resistant pancreatic cancer cells. Clinically, ZDHHC9 is upregulated in pancreatic cancer and correlated with poor prognoses for patients. Overall, our findings identify ZDHHC9-mediated palmitoylation as a positive regulator of LDHA, with potentially significant implications for cancer etiology and targeted therapy for pancreatic cancer.
Assuntos
L-Lactato Desidrogenase , Neoplasias Pancreáticas , Humanos , L-Lactato Desidrogenase/genética , Lipoilação , Linhagem Celular Tumoral , Lactato Desidrogenase 5/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Glicólise , Proliferação de Células , LactatosRESUMO
Salvianolic acid B (Sal B) is the primary water-soluble bioactive constituent derived from the roots of Salvia miltiorrhiza Bunge. This research was designed to reveal the potential mechanism of Sal B anti-liver injury from the perspective of macrophages. In our lipopolysaccharide-induced M1 macrophage model, Sal B showed a clear dose-dependent gradient of inhibition of the macrophage trend of the M1 type. Moreover, Sal B downregulated the expression of lactate dehydrogenase A (LDHA), while the overexpression of LDHA impaired Sal B's effect of inhibiting the trend of macrophage M1 polarization. Additionally, this study revealed that Sal B exhibited inhibitory effects on the lactylation process of histone H3 lysine 18 (H3K18la). In a ChIP-qPCR analysis, Sal B was observed to drive a reduction in H3K18la levels in the promoter region of the LDHA, NLRP3, and IL-1ß genes. Furthermore, our in vivo experiments showed that Sal B has a good effect on alleviating CCl4-induced liver injury. An examination of liver tissues and the Kupffer cells isolated from those tissues proved that Sal B affects the M1 polarization of macrophages and the level of histone lactylation. Together, our data reveal that Sal B has a potential mechanism of inhibiting the histone lactylation of macrophages by downregulating the level of LDHA in the treatment of liver injury.
Assuntos
Benzofuranos , Depsídeos , Histonas , Ácido Láctico , Fígado , Macrófagos , Lactato Desidrogenase 5RESUMO
Renal cell carcinoma (RCC) is one of the three major malignant tumors of the urinary system and originates from proximal tubular epithelial cells. Clear cell renal cell carcinoma (ccRCC) accounts for approximately 80% of RCC cases and is recognized as a metabolic disease driven by genetic mutations and epigenetic alterations. Through bioinformatic analysis, we found that FK506 binding protein 10 (FKBP10) may play an essential role in hypoxia and glycolysis pathways in ccRCC progression. Functionally, FKBP10 promotes the proliferation and metastasis of ccRCC in vivo and in vitro depending on its peptidyl-prolyl cis-trans isomerase (PPIase) domains. Mechanistically, FKBP10 binds directly to lactate dehydrogenase A (LDHA) through its C-terminal region, the key regulator of glycolysis, and enhances the LDHA-Y10 phosphorylation, which results in a hyperactive Warburg effect and the accumulation of histone lactylation. Moreover, HIFα negatively regulates the expression of FKBP10, and inhibition of FKBP10 enhances the antitumor effect of the HIF2α inhibitor PT2385. Therefore, our study demonstrates that FKBP10 promotes clear cell renal cell carcinoma progression and regulates sensitivity to HIF2α blockade by facilitating LDHA phosphorylation, which may be exploited for anticancer therapy.
Assuntos
Carcinoma de Células Renais , Carcinoma , Neoplasias Renais , Humanos , Carcinoma de Células Renais/metabolismo , Lactato Desidrogenase 5/metabolismo , Fosforilação , Linhagem Celular Tumoral , Carcinoma/genética , Neoplasias Renais/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Proteínas de Ligação a Tacrolimo/genética , Proteínas de Ligação a Tacrolimo/metabolismoRESUMO
The dynamic changes of RNA N6-methyladenosine (m6A) during cancer progression participate in various cellular processes. However, less is known about a possible direct connection between upstream regulator and m6A modification, and therefore affects oncogenic progression. Here, we have identified that a key enzyme in N4-acetylcytidine (ac4C) acetylation NAT10 is highly expressed in human osteosarcoma tissues, and its knockdown enhanced m6A contents and significantly suppressed osteosarcoma cell growth, migration and invasion. Further results revealed that NAT10 silence inhibits mRNA stability and translation of m6A reader protein YTHDC1, and displayed an increase in glucose uptake, a decrease in lactate production and pyruvate content. YTHDC1 recognizes differential m6A sites on key enzymes of glycolysis phosphofructokinase (PFKM) and lactate dehydrogenase A (LDHA) mRNAs, which suppress glycolysis pathway by increasing mRNA stability of them in an m6A methylation-dependent manner. YTHDC1 partially abrogated the inhibitory effect caused by NAT10 knockdown in tumor models in vivo, lentiviral overexpression of YTHDC1 partially restored the reduced stability of YTHDC1 caused by lentiviral depleting NAT10 at the cellular level. Altogether, we found ac4C driven RNA m6A modification can positively regulate the glycolysis of cancer cells and reveals a previously unrecognized signaling axis of NAT10/ac4C-YTHDC1/m6A-LDHA/PFKM in osteosarcoma. Video Abstract.