RESUMEN
Coordination of cellular metabolism is essential for optimal T cell responses. Here, we identify cytosolic acetyl-CoA production as an essential metabolic node for CD8 T cell function in vivo. We show that CD8 T cell responses to infection depend on acetyl-CoA derived from citrate via the enzyme ATP citrate lyase (ACLY). However, ablation of ACLY triggers an alternative, acetate-dependent pathway for acetyl-CoA production mediated by acyl-CoA synthetase short-chain family member 2 (ACSS2). Mechanistically, acetate fuels both the TCA cycle and cytosolic acetyl-CoA production, impacting T cell effector responses, acetate-dependent histone acetylation, and chromatin accessibility at effector gene loci. When ACLY is functional, ACSS2 is not required, suggesting acetate is not an obligate metabolic substrate for CD8 T cell function. However, loss of ACLY renders CD8 T cells dependent on acetate (via ACSS2) to maintain acetyl-CoA production and effector function. Together, ACLY and ACSS2 coordinate cytosolic acetyl-CoA production in CD8 T cells to maintain chromatin accessibility and T cell effector function.
Asunto(s)
ATP Citrato (pro-S)-Liasa , Acetatos , Acetilcoenzima A , Linfocitos T CD8-positivos , Cromatina , Ratones Endogámicos C57BL , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Animales , Cromatina/metabolismo , Acetilcoenzima A/metabolismo , ATP Citrato (pro-S)-Liasa/metabolismo , ATP Citrato (pro-S)-Liasa/genética , Ratones , Acetatos/metabolismo , Acetato CoA Ligasa/metabolismo , Acetato CoA Ligasa/genética , Acetilación , Ratones Noqueados , Citosol/metabolismo , Histonas/metabolismoRESUMEN
An extensive phytochemical investigation on the EtOAc-soluble fraction of the 90% MeOH extract from the twigs and needles of the 'vulnerable' Chinese endemic conifer Tsuga forrestii (Forrest's hemlock) led to the isolation and characterization of 50 structurally diverse diterpenoids, including 15 unreported C-18 carboxylated ones (tsugaforrestiacids A-O, 1-15, resp.). Among them, compounds 1-7 are abieten-18-oic acids, compound 8 is an abieten-18-succinate, and compounds 10-12 are podocarpen-18-oic acids, whereas compounds 13-15 are pimarane-type, isopimarane-type, and totarane-type diterpenoid acids, respectively. Their structures and absolute configurations were determined by a combination of spectroscopic methods, GIAO NMR calculations and DP4+ probability analyses, electronic circular dichroism (ECD) data, and single crystal X-ray diffraction analyses. All the isolates were evaluated for their inhibitory activities against the ATP-citrate lyase (ACL), a key enzyme in cellular metabolism. Tsugaforrestiacids E (5) and H (8) were found to have significant inhibitory effects against ACL, with IC50 values of 5.3 and 6.2 µM, respectively. The interactions of the bioactive molecules with the ACL enzyme were examined by molecular docking studies. The isolated diterpenoids also provide chemotaxonomic evidence to support the delimitation of Tsuga from its closest sister group (Nothotsuga). The above findings highlight the importance of protecting plant species with unique and diverse secondary metabolites, which may be potential sources of new therapeutic agents for the treating ACL-associated diseases.
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ATP Citrato (pro-S)-Liasa , Diterpenos , Fitoquímicos , Diterpenos/química , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , ATP Citrato (pro-S)-Liasa/antagonistas & inhibidores , ATP Citrato (pro-S)-Liasa/metabolismo , Fitoquímicos/farmacología , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , China , Estructura Molecular , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Especies en Peligro de Extinción , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad , Hojas de la Planta/químicaRESUMEN
ATP-citrate lyase (ACLY) links carbohydrate and lipid metabolism and provides nucleocytosolic acetyl-CoA for protein acetylation. ACLY has two major splice isoforms: the full-length canonical "long" isoform and an uncharacterized "short" isoform in which exon 14 is spliced out. Exon 14 encodes 10 amino acids within an intrinsically disordered region and includes at least one dynamically phosphorylated residue. Both isoforms are expressed in healthy tissues to varying degrees. Analysis of human transcriptomic data revealed that the percent spliced in (PSI) of exon 14 is increased in several cancers and correlated with poorer overall survival in a pan-cancer analysis, though not in individual tumor types. This prompted us to explore potential biochemical and functional differences between ACLY isoforms. Here, we show that there are no discernible differences in enzymatic activity or stability between isoforms or phosphomutants of ACLY in vitro. Similarly, both isoforms and phosphomutants were able to rescue ACLY functions, including fatty acid synthesis and bulk histone acetylation, when re-expressed in Acly knockout cells. Deletion of Acly exon 14 in mice did not overtly impact development or metabolic physiology nor did it attenuate tumor burden in a genetic model of intestinal cancer. Notably, expression of epithelial splicing regulatory protein 1 (ESRP1) is highly correlated with ACLY PSI. We report that ACLY splicing is regulated by ESRP1. In turn, both ESRP1 expression and ACLY PSI are correlated with specific immune signatures in tumors. Despite these intriguing patterns of ACLY splicing in healthy and cancer tissues, functional differences between the isoforms remain elusive.
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ATP Citrato (pro-S)-Liasa , Empalme Alternativo , Neoplasias , Humanos , Animales , Ratones , ATP Citrato (pro-S)-Liasa/metabolismo , ATP Citrato (pro-S)-Liasa/genética , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Fenotipo , Exones , AcetilaciónRESUMEN
Berberine was used as the lead compound in the present study to design and synthesize novel berberine derivatives by splicing bromine bridges of different berberine carbon chain lengths coupled nitric oxide donors, and their lipid lowering activities were assessed in a variety of ways. This experiment synthesized 17 new berberine nitric oxide donor derivatives. Compared with berberine hydrochloride, most of the compounds exhibited certain glycerate inhibitory activity, and compounds 6a, 6b, 6d, 12b and 12d showed higher inhibitory activity than berberine, with 6a, 6b and 6d having significant inhibitory activity. In addition, compound 6a linked to furazolidone nitric oxide donor showed better NO release in experiments; In further mechanistic studies, we screened and got two proteins, PCSK9 and ACLY, and docked two proteins with 17 compounds, and found that most of the compounds bound better with ATP citrate lyase (ACLY), among which there may be a strong interaction between compound 6a and ACLY, and the interaction force was better than the target drug Bempedoic Acid, which meaning that 6a may exert hypolipidemic effects by inhibiting ACLY; moreover, we also found that 6a may had the better performance in gastrointestinal absorption, blood-brain barrier permeability, Egan, Muegge class drug principle model calculation and bioavailability.
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Berberina , Hipolipemiantes , Donantes de Óxido Nítrico , Berberina/farmacología , Berberina/análogos & derivados , Berberina/síntesis química , Berberina/química , Hipolipemiantes/farmacología , Hipolipemiantes/síntesis química , Hipolipemiantes/química , Donantes de Óxido Nítrico/farmacología , Donantes de Óxido Nítrico/síntesis química , Donantes de Óxido Nítrico/química , Humanos , Estructura Molecular , ATP Citrato (pro-S)-Liasa/antagonistas & inhibidores , ATP Citrato (pro-S)-Liasa/metabolismo , Proproteína Convertasa 9/metabolismo , Simulación del Acoplamiento Molecular , Animales , Barrera Hematoencefálica/efectos de los fármacos , Óxido Nítrico/metabolismo , Inhibidores de PCSK9RESUMEN
The impaired osteogenic capability of bone marrow mesenchymal stem cells (BMSCs) caused by persistent inflammation is the main pathogenesis of inflammatory bone diseases. Recent studies show that metabolism is disturbed in osteogenically differentiated BMSCs in response to Lipopolysaccharide (LPS) treatment, while the mechanism involved remains incompletely revealed. Herein, we demonstrated that BMSCs adapted their metabolism to regulate acetyl-coenzyme A (acetyl-CoA) availability and RNA acetylation level, ultimately affecting osteogenic differentiation. The mitochondrial dysfunction and impaired osteogenic potential upon inflammatory conditions accompanied by the reduced acetyl-CoA content, which in turn suppressed N4-acetylation (ac4C) level. Supplying acetyl-CoA by sodium citrate (SC) addition rescued ac4C level and promoted the osteogenic capacity of LPS-treated cells through the ATP citrate lyase (ACLY) pathway. N-acetyltransferase 10 (NAT10) inhibitor remodelin reduced ac4C level and consequently impeded osteogenic capacity. Meanwhile, the osteo-promotive effect of acetyl-CoA-dependent ac4C might be attributed to fatty acid oxidation (FAO), as evidenced by activating FAO by L-carnitine supplementation counteracted remodelin-induced inhibition of osteogenesis. Further in vivo experiments confirmed the promotive role of acetyl-CoA in the endogenous bone regeneration in rat inflammatory mandibular defects. Our study uncovered a metabolic-epigenetic axis comprising acetyl-CoA and ac4C modification in the process of inflammatory osteogenesis of BMSCs and suggested a new target for bone tissue repair in the context of inflammatory bone diseases.
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Acetilcoenzima A , Diferenciación Celular , Lipopolisacáridos , Células Madre Mesenquimatosas , Osteogénesis , Animales , Osteogénesis/efectos de los fármacos , Acetilcoenzima A/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Diferenciación Celular/efectos de los fármacos , Acetilación , Células Cultivadas , Ratas , Masculino , Ratas Sprague-Dawley , ATP Citrato (pro-S)-Liasa/metabolismo , Acetiltransferasas/metabolismo , Acetiltransferasas/genéticaRESUMEN
ATP citrate lyase, the first rate-limiting enzyme in de novo lipogenesis, plays a crucial role in tumour progression. This study explores ATP citrate lyase's potential as a tumour biomarker and its role in cutaneous squamous cell carcinoma. ATP citrate lyase expression patterns were analysed using TCGA and TIMER databases, and patient skin specimens were collected for immunohistochemistry to determine ATP citrate lyase levels. Cell proliferation, cell cycle, apoptosis, and c-Myc expression were assessed in A431 and SCL-1 cells. Stable cell lines with reduced ATP citrate lyase expression were obtained and subcutaneously implanted into nude mice to evaluate in vivo tumour growth. Ki67, c-Myc expression and TUNEL staining were analysed in subcutaneous tumours. ATP citrate lyase exhibited upregulation in various tumours, and showed significant associations with prognosis and immune infiltrate. Moreover, ATP citrate lyase was highly expressed in cutaneous squamous cell carcinoma. After ATP citrate lyase silencing, cutaneous squamous cell carcinoma cell growth decelerated, the cell cycle halted, cell apoptosis increased, and c-Myc expression decreased. Animal experiments revealed that, following ATP citrate lyase knockdown, tumour tissue growth slowed down, and there was a reduction in Ki-67 and c-Myc expression, accompanied by enhanced TUNEL staining. In conclusion, ATP citrate lyase may serve as a tumour biomarker. It is highly expressed in cutaneous squamous cell carcinoma and may serve as a therapeutic target.
Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Cutáneas , Ratones , Animales , Humanos , ATP Citrato (pro-S)-Liasa/genética , ATP Citrato (pro-S)-Liasa/metabolismo , Carcinoma de Células Escamosas/genética , Biomarcadores de Tumor/genética , Ratones Desnudos , Neoplasias Cutáneas/genéticaRESUMEN
BACKGROUND & AIMS: Hypertrophic scar (HS) is a skin fibroproliferative disorder occurring after burns, surgeries or traumatic injuries, and it has caused a tremendous economic and medical burden. Its molecular mechanism is associated with the abnormal proliferation and transition of fibroblasts and excessive deposition of extracellular matrix. Cartilage intermediate layer protein 2 (CILP2), highly homologous to cartilage intermediate layer protein 1 (CILP1), is mainly secreted predominantly from chondrocytes in the middle/deeper layers of articular cartilage. Recent reports indicate that CILP2 is involved in the development of fibrotic diseases. We investigated the role of CILP2 in the progression of HS. METHODS AND RESULTS: It was found in this study that CILP2 expression was significantly higher in HS than in normal skin, especially in myofibroblasts. In a clinical cohort, we discovered that CILP2 was more abundant in the serum of patients with HS, especially in the early stage of HS. In vitro studies indicated that knockdown of CILP2 suppressed proliferation, migration, myofibroblast activation and collagen synthesis of hypertrophic scar fibroblasts (HSFs). Further, we revealed that CILP2 interacts with ATP citrate lyase (ACLY), in which CILP2 stabilizes the expression of ACLY by reducing the ubiquitination of ACLY, therefore prompting Snail acetylation and avoiding reduced expression of Snail. In vivo studies indicated that knockdown of CILP2 or ACLY inhibitor, SB-204990, significantly alleviated HS formation. CONCLUSION: CILP2 exerts a vital role in hypertrophic scar formation and might be a detectable biomarker reflecting the progression of hypertrophic scar and a therapeutic target for hypertrophic scar.
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Cicatriz Hipertrófica , Factores de Transcripción de la Familia Snail , Adulto , Animales , Femenino , Humanos , Masculino , Ratones , Acetilación , Movimiento Celular , Proliferación Celular , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patología , Cicatriz Hipertrófica/genética , Fibroblastos/metabolismo , Fibroblastos/patología , Miofibroblastos/metabolismo , Miofibroblastos/patología , Factores de Transcripción de la Familia Snail/metabolismo , Factores de Transcripción de la Familia Snail/genética , ATP Citrato (pro-S)-Liasa/metabolismoRESUMEN
Disease-associated astrocyte subsets contribute to the pathology of neurologic diseases, including multiple sclerosis and experimental autoimmune encephalomyelitis1-8 (EAE), an experimental model for multiple sclerosis. However, little is known about the stability of these astrocyte subsets and their ability to integrate past stimulation events. Here we report the identification of an epigenetically controlled memory astrocyte subset that exhibits exacerbated pro-inflammatory responses upon rechallenge. Specifically, using a combination of single-cell RNA sequencing, assay for transposase-accessible chromatin with sequencing, chromatin immunoprecipitation with sequencing, focused interrogation of cells by nucleic acid detection and sequencing, and cell-specific in vivo CRISPR-Cas9-based genetic perturbation studies we established that astrocyte memory is controlled by the metabolic enzyme ATP-citrate lyase (ACLY), which produces acetyl coenzyme A (acetyl-CoA) that is used by histone acetyltransferase p300 to control chromatin accessibility. The number of ACLY+p300+ memory astrocytes is increased in acute and chronic EAE models, and their genetic inactivation ameliorated EAE. We also detected the pro-inflammatory memory phenotype in human astrocytes in vitro; single-cell RNA sequencing and immunohistochemistry studies detected increased numbers of ACLY+p300+ astrocytes in chronic multiple sclerosis lesions. In summary, these studies define an epigenetically controlled memory astrocyte subset that promotes CNS pathology in EAE and, potentially, multiple sclerosis. These findings may guide novel therapeutic approaches for multiple sclerosis and other neurologic diseases.
Asunto(s)
Astrocitos , Encefalomielitis Autoinmune Experimental , Memoria Epigenética , Esclerosis Múltiple , Animales , Femenino , Humanos , Masculino , Ratones , Acetilcoenzima A/metabolismo , Astrocitos/enzimología , Astrocitos/metabolismo , Astrocitos/patología , ATP Citrato (pro-S)-Liasa/metabolismo , Cromatina/genética , Cromatina/metabolismo , Ensamble y Desensamble de Cromatina , Secuenciación de Inmunoprecipitación de Cromatina , Sistemas CRISPR-Cas , Encefalomielitis Autoinmune Experimental/enzimología , Encefalomielitis Autoinmune Experimental/genética , Encefalomielitis Autoinmune Experimental/metabolismo , Encefalomielitis Autoinmune Experimental/patología , Inflamación/enzimología , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Esclerosis Múltiple/enzimología , Esclerosis Múltiple/genética , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patología , Análisis de Expresión Génica de una Sola Célula , Transposasas/metabolismoRESUMEN
Lipid metabolic reprogramming of tumor cells has been proven to play a critical role in tumor initiation and development. However, lipid metabolism in cancer-associated fibroblasts (CAFs) has rarely been studied, particularly in CAFs of oral squamous cell carcinoma (OSCC). Additionally, the molecular mechanism by which tumor cells regulate lipid metabolism in fibroblasts is unclear. In this study, we found that phosphorylated ATP citrate lyase (p-ACLY), a key lipid metabolic enzyme, was upregulated in OSCC CAFs. Compared to paracancerous normal fibroblasts, CAFs showed enhanced lipid synthesis, such as elevated cytosolic acetyl-CoA level and accumulation of lipid droplets. Conversely, reduction of p-ACLY level blocked this biological process. In addition, blocking lipid synthesis in CAFs or inhibiting fatty acid uptake by OSCC cells reduced the promotive effects of CAFs on OSCC cell proliferation, invasion, and migration. These findings suggested that CAFs are one of lipid sources required for OSCC progression. Mechanistically, AKT signaling activation was involved in the upregulation of p-ACLY level and lipid synthesis in CAFs. Interleukin-8 (IL8), an exocrine cytokine of OSCC cells, could activate AKT and then phosphorylate ACLY in fibroblasts. This study suggested that the IL8/AKT/p-ACLY axis could be considered as a potential target for OSCC treatment.
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ATP Citrato (pro-S)-Liasa , Fibroblastos Asociados al Cáncer , Carcinoma de Células Escamosas , Progresión de la Enfermedad , Interleucina-8 , Proteínas Proto-Oncogénicas c-akt , Animales , Humanos , Masculino , Ratones , ATP Citrato (pro-S)-Liasa/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Interleucina-8/metabolismo , Metabolismo de los Lípidos , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Regulación hacia ArribaRESUMEN
OBJECTIVE: Mucosal T cells play a major role in inflammatory bowel disease (IBD). However, their immunometabolism during intestinal inflammation is poorly understood. Due to its impact on cellular metabolism and proinflammatory immune cell function, we here focus on the enzyme ATP citrate lyase (ACLY) in mucosal T cell immunometabolism and its relevance for IBD. DESIGN: ACLY expression and its immunometabolic impact on colitogenic T cell function were analysed in mucosal T cells from patients with IBD and in two experimental colitis models. RESULTS: ACLY was markedly expressed in colon tissue under steady-state conditions but was significantly downregulated in lamina propria mononuclear cells in experimental dextran sodium sulfate-induced colitis and in CD4+ and to a lesser extent in CD8+ T cells infiltrating the inflamed gut in patients with IBD. ACLY-deficient CD4+ T cells showed an impaired capacity to induce intestinal inflammation in a transfer colitis model as compared with wild-type T cells. Assessment of T cell immunometabolism revealed that ACLY deficiency dampened the production of IBD-relevant cytokines and impaired glycolytic ATP production but enriched metabolites involved in the biosynthesis of phospholipids and phosphatidylcholine. Interestingly, the short-chain fatty acid butyrate was identified as a potent suppressor of ACLY expression in T cells, while IL-36α and resolvin E1 induced ACLY levels. In a translational approach, in vivo administration of the butyrate prodrug tributyrin downregulated mucosal infiltration of ACLYhigh CD4+ T cells and ameliorated chronic colitis. CONCLUSION: ACLY controls mucosal T cell immunometabolism and experimental colitis. Therapeutic modulation of ACLY expression in T cells emerges as a novel strategy to promote the resolution of intestinal inflammation.
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Colitis , Enfermedades Inflamatorias del Intestino , Linfocitos Intraepiteliales , Humanos , Animales , Linfocitos Intraepiteliales/metabolismo , ATP Citrato (pro-S)-Liasa/metabolismo , Linfocitos T CD8-positivos/metabolismo , Colitis/metabolismo , Inflamación/metabolismo , Butiratos , Mucosa Intestinal/metabolismo , Sulfato de Dextran , Modelos Animales de EnfermedadRESUMEN
The 2'3'-cyclic GMP-AMP (cGAMP) synthase (cGAS)-stimulator of IFN genes (STING) pathway can sense infection and cellular stress by detecting cytosolic DNA. Upon ligand binding, cGAS produces the cyclic dinucleotide messenger cGAMP, which triggers its receptor STING. Active STING initiates gene transcription through the transcription factors IFN regulatory factor 3 (IRF3) and NF-κB and induces autophagy, but whether STING can cause changes in the metabolism of macrophages is unknown. In this study, we report that STING signaling activates ATP-citrate lyase (ACLY) by phosphorylation in human macrophages. Using genetic and pharmacologic perturbation, we show that STING targets ACLY via its prime downstream signaling effector TANK (TRAF family member-associated NF-κB activator)-binding kinase 1 (TBK1). We further identify that TBK1 alters cellular metabolism upon cGAMP treatment. Our results suggest that STING-mediated metabolic reprogramming adjusts the cellular response to DNA sensing in addition to transcription factor activation and autophagy induction.
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FN-kappa B , Proteínas Serina-Treonina Quinasas , Humanos , ATP Citrato (pro-S)-Liasa/metabolismo , ADN , Factor 3 Regulador del Interferón/metabolismo , Macrófagos/metabolismo , Proteínas de la Membrana/metabolismo , FN-kappa B/metabolismo , Nucleotidiltransferasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismoRESUMEN
ATP citrate lyase (ACLY), a strategic metabolic enzyme that catalyzes the glycolytic to lipidic metabolism, has gained increasing attention as an attractive therapeutic target for hyperlipidemia, cancers and other human diseases. Despite of continual research efforts, targeting ACLY has been very challenging. In this field, most reported ACLY inhibitors are "substrate-like" analogues, which occupied with the same active pockets. Besides, some ACLY inhibitors have been disclosed through biochemical screening or high throughput virtual screening. In this review, we briefly summarized the cancer-related functions and the recent advance of ACLY inhibitors with a particular focus on the SAR studies and their modes of action. We hope to provide a timely and updated overview of ACLY and the discovery of new ACLY inhibitors.
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ATP Citrato (pro-S)-Liasa , Neoplasias , Humanos , ATP Citrato (pro-S)-Liasa/metabolismo , Neoplasias/metabolismo , Metabolismo de los LípidosRESUMEN
Objective To investigate the role of ATP citrate lyase(ACLY)in the development of hepatocellular carcinoma(HCC)and the impact of this enzyme on the immune microenvironment of HCC.Methods We utilized the University of Alabama at Birmingham Cancer Data Analysis Portal and the Gene Expression Profiling Interactive Analysis to identify the changes in ACLY expression and prognosis across different tumor types from The Cancer Genome Atlas.With HCC as the disease model,we analyzed the ACLY expression in HCC samples from the gene expression database.Furthermore,we collected the clinical specimens from HCC patients to verify the mRNA and protein levels of ACLY.In addition,we conducted transcriptome sequencing after knocking down the expression of ACLY to analyze the differentially expressed genes and investigated the impact of ACLY expression interference on cell proliferation and other functions.Finally,we explored the correlations of ACLY with immune cells and immune infiltration in the tumor microenvironment,new antigens,and immune checkpoint genes.Results ACLY expression was significantly up-regulated in solid tumors including HCC(all P<0.05),and high ACLY expression was associated with overall survival rate in HCC(P=0.005).Furthermore,high ACLY expression affected the presence of immune cells(e.g.,tumor-associated fibroblasts)and the expression of genes involved in lipid metabolism(all P<0.05).Conclusions ACLY is closely related to the occurrence and development of HCC and lipid metabolism abnormalities.Moreover,it has a specific impact on the immune microenvironment of HCC.
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ATP Citrato (pro-S)-Liasa , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , ATP Citrato (pro-S)-Liasa/genética , ATP Citrato (pro-S)-Liasa/metabolismo , Relevancia Clínica , Metabolismo de los Lípidos , Microambiente TumoralRESUMEN
Mounting evidence indicates the potential involvement of ATP-citrate lyase (ACLY) in the modulation of various cancer types. Nevertheless, the precise biological significance of ACLY in gastric cancer (GC) remains elusive. This study sought to elucidate the biological function of ACLY and uncover its influence on peritoneal metastasis in GC. The expression of ACLY was assessed using both real-time quantitative PCR and western blot techniques. To investigate the impact of ACLY on the proliferation of gastric cancer (GC) cells, colony formation and 5-ethynyl-2'-deoxyuridine (EdU) assays were performed. The migratory and invasive abilities of GC were evaluated using wound healing and transwell assays. Additionally, a bioinformatics analysis was employed to predict the correlation between ACLY and HIF-1A. This interaction was subsequently confirmed through a chromatin immunoprecipitation (ChIP) assay. ACLY exhibited upregulation in gastric cancer (GC) as well as in peritoneal metastasis. Its overexpression was found to facilitate the proliferation and metastasis of GC cells in both in vitro and in vivo experiments. Moreover, ACLY was observed to play a role in promoting angiogenesis and epithelial-mesenchymal transition (EMT). Notably, under hypoxic conditions, HIF-1A levels were elevated, thereby acting as a transcription factor to upregulate ACLY expression. Under the regulatory influence of HIF-1A, ACLY exerts a significant impact on the progression of gastric cancer, thereby facilitating peritoneal metastasis.
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Neoplasias Peritoneales , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patología , ATP Citrato (pro-S)-Liasa/metabolismo , Neoplasias Peritoneales/genética , Proliferación Celular/genética , Transformación Celular Neoplásica , Transición Epitelial-Mesenquimal/genética , Línea Celular TumoralRESUMEN
Inflammation-dependent changes in gene expression programs in innate immune cells, such as macrophages, involve extensive reprogramming of metabolism. This reprogramming is essential for the production of metabolites required for chromatin modifications, such as acetyl-CoA, and regulate their usage and availability impacting the macrophage epigenome. One of the most transcriptionally induced proinflammatory mediator is nitric oxide (NO), which has been shown to inhibit key metabolic enzymes involved in the production of these metabolites. Recent evidence indicates that NO inhibits mitochondrial enzymes such as pyruvate dehydrogenase (PDH) in macrophages induced by inflammatory stimulus. PDH is involved in the production of acetyl-CoA, which is essential for chromatin modifications in the nucleus, such as histone acetylation. In addition, acetyl-CoA levels in inflamed macrophages are regulated by ATP citrate lyase (ACLY) and citrate transporter SLC25A1. Interestingly, acetyl-CoA producing enzymes, such as PDH and ACLY, have also been reported to be present in the nucleus and to support the local generation of cofactors such as acetyl-CoA. Here, we will discuss the mechanisms involved in the regulation of acetyl-CoA production by metabolic enzymes, their inhibition by prolonged exposure to inflammation stimuli, their involvement in dynamic inflammatory expression changes and how these emerging findings could have significant implications for the design of novel therapeutic approaches.
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ATP Citrato (pro-S)-Liasa , Epigénesis Genética , Humanos , Acetilcoenzima A/metabolismo , ATP Citrato (pro-S)-Liasa/genética , ATP Citrato (pro-S)-Liasa/metabolismo , Inflamación/genética , Aciltransferasas/genética , CromatinaRESUMEN
Melanoma is the most lethal skin cancer originating from the malignant transformation of epidermal melanocyte. The dysregulation of cellular metabolism is a hallmark of cancer, including in melanoma. Aberrant branched-chain amino acids (BCAA) metabolism and related enzymes has been greatly implicated in the progression of multiple types of cancer, whereas remains far from understood in melanoma. Herein, we reported that the critical BCAA metabolism enzyme branched-chain amino acid transaminase 2 (BCAT2) is an oncogenic factor in melanoma by activating lipogenesis via the epigenetic regulation of fatty acid synthase (FASN) and ATP-citrate lyase (ACLY) expressions. Firstly, we found that BCAT2 expression was prominently increased in melanoma, and highly associated with clinical stage. Then, it was proved that the deficiency of BCAT2 led to impaired tumor cell proliferation, invasion and migration in vitro, and tumor growth and metastasis in vivo. Further, RNA sequencing technology and a panel of biochemical assays demonstrated that BCAT2 regulated de novo lipogenesis via the regulation of the expressions of both FASN and ACLY. Mechanistically, the inhibition of BCAT2 suppressed the generation of intracellular acetyl-CoA, mitigating P300-dependent histone acetylation at the promoter of FASN and ACLY, and thereby their transcription. Ultimately, zinc finger E-box binding homeobox 1 (ZEB1) was identified as the upstream transcriptional factor responsible for BCAT2 up-regulation in melanoma. Our results demonstrate that BCAT2 promotes melanoma progression by epigenetically regulating FASN and ACLY expressions via P300-dependent histone acetylation. Targeting BCAT2 could be exploited as a promising strategy to restrain tumor progression in melanoma.
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Melanoma , Proteínas Gestacionales , Humanos , Lipogénesis/genética , ATP Citrato (pro-S)-Liasa/genética , ATP Citrato (pro-S)-Liasa/metabolismo , Histonas/metabolismo , Epigénesis Genética , Melanoma/genética , Transaminasas/genética , Proteínas Gestacionales/genética , Proteínas Gestacionales/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Acido Graso Sintasa Tipo I/genéticaRESUMEN
The hepatic SLC13A5/SLC25A1-ATP-dependent citrate lyase (ACLY) signaling pathway, responsible for maintaining the citrate homeostasis, plays a crucial role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Bempedoic acid (BA), an ACLY inhibitor commonly used for managing hypercholesterolemia, has shown promising results in addressing hepatic steatosis. This study aimed to elucidate the intricate relationships in processes of hepatic lipogenesis among SLC13A5, SLC25A1, and ACLY and to examine the therapeutic potential of BA in NAFLD, providing insights into its underlying mechanism. In murine primary hepatocytes and HepG2 cells, the silencing or pharmacological inhibition of SLC25A1/ACLY resulted in significant upregulation of SLC13A5 transcription and activity. This increase in SLC13A5 activity subsequently led to enhanced lipogenesis, indicating a compensatory role of SLC13A5 when the SLC25A1/ACLY pathway was inhibited. However, BA effectively counteracted this upregulation, reduced lipid accumulation, and ameliorated various biomarkers of NAFLD. The disease-modifying effects of BA were further confirmed in NAFLD mice. Mechanistic investigations revealed that BA could reverse the elevated transcription levels of SLC13A5 and ACLY, and the subsequent lipogenesis induced by PXR activation in vitro and in vivo. Importantly, this effect was diminished when PXR was knocked down, suggesting the involvement of the hepatic PXR-SLC13A5/ACLY signaling axis in the mechanism of BA action. In conclusion, SLC13A5-mediated extracellular citrate influx emerges as an alternative pathway to SLC25A1/ACLY in the regulation of lipogenesis in hepatocytes, BA exhibits therapeutic potential in NAFLD by suppressing the hepatic PXR-SLC13A5/ACLY signaling axis, while PXR, a key regulator in drug metabolism may be involved in the pathogenesis of NAFLD. SIGNIFICANCE STATEMENT: This work describes that bempedoic acid, an ATP-dependent citrate lyase (ACLY) inhibitor, ameliorates hepatic lipid accumulation and various hallmarks of non-alcoholic fatty liver disease. Suppression of hepatic SLC25A1-ACLY pathway upregulates SLC13A5 transcription, which in turn activates extracellular citrate influx and the subsequent DNL. Whereas in hepatocytes or the liver tissue challenged with high energy intake, bempedoic acid reverses compensatory activation of SLC13A5 via modulating the hepatic PXR-SLC13A5/ACLY axis, thereby simultaneously downregulating SLC13A5 and ACLY.
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Enfermedad del Hígado Graso no Alcohólico , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/metabolismo , ATP Citrato (pro-S)-Liasa/metabolismo , Hígado/metabolismo , Ácidos Grasos/metabolismo , Transducción de Señal , Citratos/metabolismo , Ácido Cítrico/metabolismoRESUMEN
Importance: Adenosine triphosphate citrate lyase (ACLY) is a key regulatory enzyme of glucose metabolism, cholesterol and fatty acid synthesis, and the inflammatory cascade. Bempedoic acid, an ACLY inhibitor, significantly reduces atherogenic lipid markers, including low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol, and apolipoprotein B. Additional effects of ACLY inhibition include antitumor growth; reduction of triglycerides and proinflammatory molecules such as high-sensitivity C-reactive protein; less insulin resistance; reduction of hepatic lipogenesis; and weight loss. Observations: While numerous ACLY inhibitors have been identified, most of the clinical data have focused on bempedoic acid. The Cholesterol Lowering via Bempedoic Acid, an ACL-Inhibiting Regimen (CLEAR) program was a series of phase 3 clinical trials that evaluated its effects on lipid parameters and safety, leading to US Food and Drug Administration approval in 2020. CLEAR Outcomes was a phase 3, double-blind, randomized, placebo-controlled trial in individuals with a history of statin intolerance, serum LDL-C level of 100 mg/dL or higher, and a history of, or at high risk for, cardiovascular disease. Bempedoic acid modestly reduced the primary 4-way cardiovascular composite end point as well as the individual components of myocardial infarction and coronary revascularization but did not reduce stroke, cardiovascular death, or all-cause mortality. Rates of gout and cholelithiasis were higher with bempedoic acid, and small increases in serum creatinine, uric acid, and hepatic-enzyme levels were also observed. Conclusions and relevance: ACLY inhibition with bempedoic acid has been established as a safe and effective therapy in high-risk patients who require further LDL-C lowering, particularly for those with a history of statin intolerance. The recently published CLEAR Outcomes trial revealed modest reductions in cardiovascular events with bempedoic acid, proportional to its LDL-C lowering, in high-risk individuals with statin intolerance and LDL-C levels of 100 mg/dL or higher. The additional effects of ACLY inhibition have prompted a more thorough search for novel ACLY inhibitors for conditions such as cancer, hypertriglyceridemia, chronic inflammation, type 2 diabetes, fatty liver disease, obesity, and metabolic syndrome. Similarly, therapies that reduce fatty acid synthesis are being explored for their use in cardiometabolic conditions.
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ATP Citrato (pro-S)-Liasa , Diabetes Mellitus Tipo 2 , Ácidos Grasos , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Humanos , Colesterol , LDL-Colesterol , Ensayos Clínicos Fase III como Asunto , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Ácidos Grasos/antagonistas & inhibidores , Ácidos Grasos/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Lipogénesis , Ensayos Clínicos Controlados Aleatorios como Asunto , ATP Citrato (pro-S)-Liasa/antagonistas & inhibidores , ATP Citrato (pro-S)-Liasa/metabolismoRESUMEN
Sepsis involves endothelial cell (EC) dysfunction, which contributes to multiple organ failure. To improve therapeutic prospects, elucidating molecular mechanisms of vascular dysfunction is of the essence. ATP-citrate lyase (ACLY) directs glucose metabolic fluxes to de novo lipogenesis by generating acetyl-Co-enzyme A (acetyl-CoA), which facilitates transcriptional priming via protein acetylation. It is well illustrated that ACLY participates in promoting cancer metastasis and fatty liver diseases. Its biological functions in ECs during sepsis remain unclear. We found that plasma levels of ACLY were increased in septic patients and were positively correlated with interleukin (IL)-6, soluble E-selectin (sE-selectin), soluble vascular cell adhesion molecule 1 (sVCAM-1), and lactate levels. ACLY inhibition significantly ameliorated lipopolysaccharide challenge-induced EC proinflammatory response in vitro and organ injury in vivo. The metabolomic analysis revealed that ACLY blockade fostered ECs a quiescent status by reducing the levels of glycolytic and lipogenic metabolites. Mechanistically, ACLY promoted forkhead box O1 (FoxO1) and histone H3 acetylation, thereby increasing the transcription of c-Myc (MYC) to facilitate the expression of proinflammatory and gluco-lipogenic genes. Our findings revealed that ACLY promoted EC gluco-lipogenic metabolism and proinflammatory response through acetylation-mediated MYC transcription, suggesting ACLY as the potential therapeutic target for treating sepsis-associated EC dysfunction and organ injury.
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ATP Citrato (pro-S)-Liasa , Lipogénesis , Humanos , ATP Citrato (pro-S)-Liasa/metabolismo , Inflamación , Adenosina Trifosfato/metabolismoRESUMEN
The dysregulation of branched-chain amino acid (BCAA) metabolism and related enzymes has been greatly implicated in the progression of multiple types of cancer, whereas remains far from understood in melanoma. Here, we explored the role of the BCAA metabolism enzyme BCKDHA in melanoma pathogenesis and elucidated the underlying mechanisms. In vitro cell biology experiments and in vivo pre-clinical mice model experiments were performed to investigate the role of BCKDHA in melanoma progression. RNA sequencing, immunohistochemical/immunofluorescence staining and bioinformatics analysis were used to examine the underlying mechanism. BCKDHA expression was prominently increased in both melanoma tissues and cell lines. The up-regulation of BCKDHA promoted long-term tumour cell proliferation, invasion and migration in vitro and tumour growth in vivo. Through RNA-sequencing technology, it was found that BCKDHA regulated the expressions of lipogenic fatty acid synthase (FASN) and ATP-citrate lyase (ACLY), which was thereafter proved to mediate the oncogenic role of BCKDHA in melanoma. Our results demonstrate that BCKDHA promotes melanoma progression by regulating FASN and ACLY expressions. Targeting BCKDHA could be exploited as a promising strategy to restrain tumour progression in melanoma.