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de Kivit S, Mensink M, Hoekstra AT, Berlin I, Derks RJE, Both D, Aslam MA, Amsen D, Berkers CR, Borst J. Stable human regulatory T cells switch to glycolysis following TNF receptor 2 costimulation. Nat Metab 2020; 2:1046-1061. [PMID: 32958937 DOI: 10.1038/s42255-020-00271-w] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 07/27/2020] [Indexed: 01/08/2023]
Abstract
Following activation, conventional T (Tconv) cells undergo an mTOR-driven glycolytic switch. Regulatory T (Treg) cells reportedly repress the mTOR pathway and avoid glycolysis. However, here we demonstrate that human thymus-derived Treg (tTreg) cells can become glycolytic in response to tumour necrosis factor receptor 2 (TNFR2) costimulation. This costimulus increases proliferation and induces a glycolytic switch in CD3-activated tTreg cells, but not in Tconv cells. Glycolysis in CD3-TNFR2-activated tTreg cells is driven by PI3-kinase-mTOR signalling and supports tTreg cell identity and suppressive function. In contrast to glycolytic Tconv cells, glycolytic tTreg cells do not show net lactate secretion and shuttle glucose-derived carbon into the tricarboxylic acid cycle. Ex vivo characterization of blood-derived TNFR2hiCD4+CD25hiCD127lo effector T cells, which were FOXP3+IKZF2+, revealed an increase in glucose consumption and intracellular lactate levels, thus identifying them as glycolytic tTreg cells. Our study links TNFR2 costimulation in human tTreg cells to metabolic remodelling, providing an additional avenue for drug targeting.
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Humphries F, Shmuel-Galia L, Ketelut-Carneiro N, Li S, Wang B, Nemmara VV, Wilson R, Jiang Z, Khalighinejad F, Muneeruddin K, Shaffer SA, Dutta R, Ionete C, Pesiridis S, Yang S, Thompson PR, Fitzgerald KA. Succination inactivates gasdermin D and blocks pyroptosis. Science 2020; 369:1633-1637. [PMID: 32820063 PMCID: PMC8744141 DOI: 10.1126/science.abb9818] [Citation(s) in RCA: 340] [Impact Index Per Article: 85.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 08/05/2020] [Indexed: 12/12/2022]
Abstract
Activated macrophages undergo a metabolic switch to aerobic glycolysis, accumulating Krebs' cycle intermediates that alter transcription of immune response genes. We extended these observations by defining fumarate as an inhibitor of pyroptotic cell death. We found that dimethyl fumarate (DMF) delivered to cells or endogenous fumarate reacts with gasdermin D (GSDMD) at critical cysteine residues to form S-(2-succinyl)-cysteine. GSDMD succination prevents its interaction with caspases, limiting its processing, oligomerization, and capacity to induce cell death. In mice, the administration of DMF protects against lipopolysaccharide shock and alleviates familial Mediterranean fever and experimental autoimmune encephalitis by targeting GSDMD. Collectively, these findings identify GSDMD as a target of fumarate and reveal a mechanism of action for fumarate-based therapeutics that include DMF, for the treatment of multiple sclerosis.
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Ogasawara E, Nakada K, Ishihara N. Distal control of mitochondrial biogenesis and respiratory activity by extracellular lactate caused by large-scale deletion of mitochondrial DNA. Pharmacol Res 2020; 160:105204. [PMID: 32946932 DOI: 10.1016/j.phrs.2020.105204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/20/2020] [Accepted: 09/09/2020] [Indexed: 12/30/2022]
Abstract
Lactate is highly produced under conditions of respiratory dysfunction such as anaerobic respiration and various types of mitochondrial diseases, and it was also known as an active molecule that plays various roles both within and between cells. High levels of extracellular lactate may lead to lactic acidosis, which has been related to pathology of the mitochondrial diseases with mutated mitochondrial DNA (mtDNA). In this study, to elucidate the poorly understood molecular roles of extracellular lactate in mitochondrial regulation, we analyzed mouse B82 cells and their cybrid cells carrying mutated mtDNA with a large-scale deletion (ΔmtDNA). Inhibition of lactate production by sodium dichloroacetate (DCA) treatment improved mitochondrial respiration in cells carrying ΔmtDNA through the activation of mitochondrial biogenesis. Chronic exposure to extracellular lactate (more than 3 days) repressed mitochondrial respiration in healthy cells via calcium and CaMK signaling, leading to a decrease in PGC1α-mediated mitochondrial biogenesis. These mitochondrial dysfunctions induced by the lactate treatment were repressed by pH buffering of the medium. These results suggest that lactate, produced in respiration-deficient cells, acts not only as an intracellular source of energy through the TCA cycle, but also as an extracellular messenger molecule regulating the respiratory activity of both cells carrying ΔmtDNA and the surrounding cells, which could cause whole-body repression of respiratory activity.
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Bencze G, Bencze S, Rivera KD, Watson JD, Hidvegi M, Orfi L, Tonks NK, Pappin DJ. Mito-oncology agent: fermented extract suppresses the Warburg effect, restores oxidative mitochondrial activity, and inhibits in vivo tumor growth. Sci Rep 2020; 10:14174. [PMID: 32843660 PMCID: PMC7447799 DOI: 10.1038/s41598-020-71118-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 08/10/2020] [Indexed: 01/15/2023] Open
Abstract
Mitochondrial dysfunction and significant changes in metabolic pathways accompany cancer development and are responsible for maintaining the tumor microenvironment. Normal mitochondria can trigger intrinsic apoptosis by releasing cytochrome c into the cytosol. The survival of malignant cells highly depends on the suppression of this function. We validated that A250, a highly purified fraction of fermented wheat germ extract (FWGE), increases the carbon flux into the mitochondria, the expression of key elements of the Krebs cycle and oxidative phosphorylation (OXPHOS). The increased respiratory chain activity is related to the mitochondria's ability to release cytochrome c into the cytosol, which triggers the apoptotic cascade. The 68% tumor growth inhibitory effect observed in the murine melanoma study is related to this effect, as proteomic analysis validated similar changes in mitochondrial protein levels in the isolated tumor tissue samples. Blood count data indicated that this effect was not accompanied by general toxicity. This study is significant, as it shows that a highly concentrated form of FWGE is an effective agent that increases normal mitochondrial functionality. The lack of hepatotoxic and general toxic effects makes A250 an excellent candidate targeting mitochondria function in cancer therapy.
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Frattaruolo L, Brindisi M, Curcio R, Marra F, Dolce V, Cappello AR. Targeting the Mitochondrial Metabolic Network: A Promising Strategy in Cancer Treatment. Int J Mol Sci 2020; 21:ijms21176014. [PMID: 32825551 PMCID: PMC7503725 DOI: 10.3390/ijms21176014] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/14/2020] [Accepted: 08/19/2020] [Indexed: 12/12/2022] Open
Abstract
Metabolic reprogramming is a hallmark of cancer, which implements a profound metabolic rewiring in order to support a high proliferation rate and to ensure cell survival in its complex microenvironment. Although initial studies considered glycolysis as a crucial metabolic pathway in tumor metabolism reprogramming (i.e., the Warburg effect), recently, the critical role of mitochondria in oncogenesis, tumor progression, and neoplastic dissemination has emerged. In this report, we examined the main mitochondrial metabolic pathways that are altered in cancer, which play key roles in the different stages of tumor progression. Furthermore, we reviewed the function of important molecules inhibiting the main mitochondrial metabolic processes, which have been proven to be promising anticancer candidates in recent years. In particular, inhibitors of oxidative phosphorylation (OXPHOS), heme flux, the tricarboxylic acid cycle (TCA), glutaminolysis, mitochondrial dynamics, and biogenesis are discussed. The examined mitochondrial metabolic network inhibitors have produced interesting results in both preclinical and clinical studies, advancing cancer research and emphasizing that mitochondrial targeting may represent an effective anticancer strategy.
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Roca-Portoles A, Rodriguez-Blanco G, Sumpton D, Cloix C, Mullin M, Mackay GM, O'Neill K, Lemgruber L, Luo X, Tait SWG. Venetoclax causes metabolic reprogramming independent of BCL-2 inhibition. Cell Death Dis 2020; 11:616. [PMID: 32792521 PMCID: PMC7426836 DOI: 10.1038/s41419-020-02867-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 07/28/2020] [Accepted: 07/29/2020] [Indexed: 11/17/2022]
Abstract
BH3-mimetics are a new class of anti-cancer drugs that inhibit anti-apoptotic Bcl-2 proteins. In doing so, BH3-mimetics sensitise to cell death. Venetoclax is a potent, BCL-2 selective BH3-mimetic that is clinically approved for use in chronic lymphocytic leukaemia. Venetoclax has also been shown to inhibit mitochondrial metabolism, this is consistent with a proposed role for BCL-2 in metabolic regulation. We used venetoclax to understand BCL-2 metabolic function. Similar to others, we found that venetoclax inhibited mitochondrial respiration. In addition, we also found that venetoclax impairs TCA cycle activity leading to activation of reductive carboxylation. Importantly, the metabolic effects of venetoclax were independent of cell death because they were also observed in apoptosis-resistant BAX/BAK-deficient cells. However, unlike venetoclax treatment, inhibiting BCL-2 expression had no effect on mitochondrial respiration. Unexpectedly, we found that venetoclax also inhibited mitochondrial respiration and the TCA cycle in BCL-2 deficient cells and in cells lacking all anti-apoptotic BCL-2 family members. Investigating the basis of this off-target effect, we found that venetoclax-induced metabolic reprogramming was dependent upon the integrated stress response and ATF4 transcription factor. These data demonstrate that venetoclax affects cellular metabolism independent of BCL-2 inhibition. This off-target metabolic effect has potential to modulate venetoclax cytotoxicity.
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Guerra ÂR, Paulino AF, Castro MM, Oliveira H, Duarte MF, Duarte IF. Triple Negative Breast Cancer and Breast Epithelial Cells Differentially Reprogram Glucose and Lipid Metabolism upon Treatment with Triterpenic Acids. Biomolecules 2020; 10:E1163. [PMID: 32784479 PMCID: PMC7464159 DOI: 10.3390/biom10081163] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 07/31/2020] [Accepted: 08/06/2020] [Indexed: 12/20/2022] Open
Abstract
Plant-derived pentacyclic triterpenic acids (TAs) have gained increasing attention due to their multiple biological activities. Betulinic acid (BA) and ursolic acid (UA) modulate diverse pathways in carcinogenesis, offering increased changes of success in refractory cancers, such as triple negative breast cancer (TNBC). The present work aimed to assess the metabolic effects of BA and UA in MDA-MB-231 breast cancer cells (TNBC model), as well as in MCF-10A non-cancer breast epithelial cells, with a view to unveiling the involvement of metabolic reprogramming in cellular responses to these TAs. Cell viability and cell cycle analyses were followed by assessment of changes in the cells exo- and endometabolome through 1H NMR analysis of cell culture medium supernatants, aqueous and organic cell extracts. In MDA-MB-231 cells, BA was suggested to induce a transient upregulation of glucose consumption and glycolytic conversion, tricarboxylic acid (TCA) cycle intensification, and hydrolysis of neutral lipids, while UA effects were much less pronounced. In MCF-10A cells, boosting of glucose metabolism by the two TAs was accompanied by diversion of glycolytic intermediates to the hexosamine biosynthetic pathway (HBP) and the synthesis of neutral lipids, possibly stored in detoxifying lipid droplets. Additionally, breast epithelial cells intensified pyruvate consumption and TCA cycle activity, possibly to compensate for oxidative impairment of pyruvate glycolytic production. This study provided novel insights into the metabolic effects of BA and UA in cancer and non-cancer breast cells, thus improving current understanding of the action of these compounds at the molecular level.
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Nagayama Y, Isoo N, Nakashima A, Suzuki K, Yamano M, Nariyama T, Yagame M, Matsui K. Renoprotective effects of paramylon, a β-1,3-D-Glucan isolated from Euglena gracilis Z in a rodent model of chronic kidney disease. PLoS One 2020; 15:e0237086. [PMID: 32764782 PMCID: PMC7413521 DOI: 10.1371/journal.pone.0237086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 07/20/2020] [Indexed: 12/25/2022] Open
Abstract
Paramylon is a novel β-glucan that is stored by Euglena gracilis Z, which is a unicellular photosynthesizing green alga with characteristics of both animals and plants. Recent studies have indicated that paramylon functions as an immunomodulator or a dietary fiber. Currently, chronic kidney disease (CKD) is a global health problem, and there is no effective preventive treatment for CKD progression. However, paramylon may suppress the progression of CKD via the elimination of uremic toxins or modulation of gut microbiota, leading to the alleviation of inflammation. The aim of this study was to evaluate the effect of paramylon in CKD rat model. Eight-week-old male Wistar rats with a 5/6 nephrectomy were given either a normal diet or a diet containing 5% paramylon for 8 weeks. Proteinuria was measured intermittently. Serum and kidney tissues were harvested after sacrifice. We performed a renal molecular and histopathological investigation, serum metabolome analysis, and gut microbiome analysis. The results showed that paramylon attenuated renal function, glomerulosclerosis, tubulointerstitial injury, and podocyte injury in the CKD rat model. Renal fibrosis, tubulointerstitial inflammatory cell infiltration, and proinflammatory cytokine gene expression levels tended to be suppressed with paramylon treatment. Further, paramylon inhibited the accumulation of uremic toxins, including tricarboxylic acid (TCA) cycle-related metabolites and modulated a part of CKD-related gut microbiota in the CKD rat model. In conclusion, we suggest that paramylon mainly inhibited the absorption of non-microbiota-derived uremic solutes, leading to protect renal injury via anti-inflammatory and anti-fibrotic effects. Paramylon may be a novel compound that can act against CKD progression.
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Jiang W, Xu S, Guo H, Lu L, Liu J, Wang G, Hao K. Magnesium isoglycyrrhizinate prevents the nonalcoholic hepatic steatosis via regulating energy homeostasis. J Cell Mol Med 2020; 24:7201-7213. [PMID: 32410294 PMCID: PMC7339216 DOI: 10.1111/jcmm.15230] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/22/2020] [Accepted: 03/06/2020] [Indexed: 12/21/2022] Open
Abstract
Non-alcoholic fatty liver disease is a public health problem worldwide associated with high morbidity and hepatic steatosis, but no effective therapeutic interventions. Magnesium isoglycyrrhizinate (MGIG), a derivative of an active component of Glycyrrhiza glabra, is widely used for the treatment of inflammatory liver diseases due to its potent anti-inflammatory and hepatoprotective activities. Hence, this study aimed to study the effects of MGIG on hepatic steatosis in mice fed a high-fat diet (HFD). Oil Red O staining and transmission electron microscopy revealed a decrease in lipid accumulation in the liver after MGIG treatment along with improved mitochondrial ultramicrostructures. Metabonomic analysis demonstrated that MGIG intervention increased glutamate utilization in mitochondria by promoting the uptake of glutamate into the tricarboxylic acid (TCA) cycle. The NAD+ /NADH ratio and the expression of other lipid-metabolism-related genes were increased in MGIG-treated livers. Transcriptome sequencing showed that the expression of TLR4, an isoform of the innate immunity Toll-like receptors (TLRs), was significantly decreased after MGIG treatment, suggesting a link between the anti-inflammatory effects of MGIG and its suppression of lipidation. Our results reveal the potent effects of MGIG on lipid metabolism and suggest that hepatic TLR4 might be a crucial therapeutic target to regulate energy homeostasis in hepatic steatosis.
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Asnani A, Shi X, Farrell L, Lall R, Sebag IA, Plana JC, Gerszten RE, Scherrer-Crosbie M. Changes in Citric Acid Cycle and Nucleoside Metabolism Are Associated with Anthracycline Cardiotoxicity in Patients with Breast Cancer. J Cardiovasc Transl Res 2020; 13:349-356. [PMID: 31278494 DOI: 10.1007/s12265-019-09897-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 06/18/2019] [Indexed: 01/04/2023]
Abstract
Anthracyclines and HER2-targeted antibodies are very effective for the treatment of breast cancer, but their use is limited by cardiotoxicity. In this nested case-control study, we assessed the role of intermediary metabolism in 38 women with breast cancer treated with anthracyclines and trastuzumab. Using targeted mass spectrometry to measure 71 metabolites in the plasma, we identified changes in citric acid and aconitic acid that differentiated patients who developed cardiotoxicity from those who did not. In patients with cardiotoxicity, the magnitude of change in citric acid at three months correlated with the change in left ventricular ejection fraction (LVEF) and absolute LVEF at nine months. Patients with cardiotoxicity also demonstrated more pronounced changes in purine and pyrimidine metabolism. Early metabolic changes may therefore provide insight into the mechanisms associated with the development of chemotherapy-associated cardiotoxicity.
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Matsumoto Y, Nakashima T, Cho O, Ohkubo T, Kato J, Sugita T. Pyruvate-triggered TCA cycle regulation in Staphylococcus aureus promotes tolerance to betamethasone valerate. Biochem Biophys Res Commun 2020; 528:318-321. [PMID: 32475641 DOI: 10.1016/j.bbrc.2020.05.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/31/2022]
Abstract
Staphylococcus aureus is a resident skin bacterium involved in the exacerbation of atopic dermatitis. Here we report that S. aureus regulates the tricarboxylic acid (TCA) cycle via the production of pyruvate for tolerance to betamethasone valerate (BV), an anti-inflammatory drug used in the treatment of atopic dermatitis. The addition of BV or clobetasol propionate to the medium among 5 different anti-inflammatory steroids delayed the growth of S. aureus. Comprehensive gene expression analysis by RNA-seq revealed that BV increased the expression of genes related to glycolysis in S. aureus. Pyruvate, a product of glycolysis, suppressed the S. aureus growth inhibition by BV. The addition of oxaloacetate, a compound in the TCA cycle biosynthesized from pyruvate, was also suppressed the inhibitory effect of BV. Malonate, an inhibitor of succinate dehydrogenase in the TCA cycle, increased the inhibitory effect of BV on the growth of S. aureus. These findings suggest that S. aureus promotes tolerance to BV, an anti-inflammatory steroid, by regulating the TCA cycle via the production of pyruvate.
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Zhao T, Yang Z, Mei X, Xu L, Fan Y. Metabolic disturbance in Korean red ginseng-induced "Shanghuo" (excessive heat). JOURNAL OF ETHNOPHARMACOLOGY 2020; 253:112604. [PMID: 31972326 DOI: 10.1016/j.jep.2020.112604] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 01/14/2020] [Accepted: 01/18/2020] [Indexed: 05/27/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Northeast China is one of the Korean Red Ginseng (KRG) producing areas. As a health care product, KRG is popular amongst Chinese people. However, few studies have reported the side effects of overusing KRG. AIM OF THE STUDY The main purpose of this study is to explore the mechanism of Korean Red Ginseng (KRG)-induced "Shanghuo" (excessive heat). MATERIALS AND METHODS After the baseline characteristics were evaluated, 30 healthy volunteers were administrated with 3g of KRG for 10-16 days and diagnosed with "Shanghuo". The volunteers prior to the administration of KRG were considered as the control group. The volunteers after being diagnosed with "Shanghuo" (excessive heat) were considered as "Shanghuo" group. The two groups were assessed by the tests of serum metabolic products, Succinate Dehydrogenase (SDH) activity, and mRNA expressions of adenosine monophosphate (AMP)-activated protein kinase (AMPK), PPARG Coactivator 1 Alpha (PGC-1α) and Nuclear Respiratory Factor 1 (NRF1). RESULTS Most of the serum metabolites in the "Shanghuo" group were increased compared with the control group, from high to low including serine, valine, heptacosane, xylose, glycerol 1-monostearate, d-glucose, 3-pyridinol, glyceryl palmitate, urea, phosphoric acid, glycerol, stearic acid, palmitic acid, cyclohexaneacetic acid. Only cholesterol was significantly reduced, The SDH activity and the mRNA expressions of AMPK, PGC-1α and NRF1 were significantly increased in the "Shanghuo" group. CONCLUSIONS Overconsumption of KRG could induce "Shanghuo", which has a close relationship with an accelerated TCA cycle and the increased AMPK activity.
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Ghosh P, Vidal C, Dey S, Zhang L. Mitochondria Targeting as an Effective Strategy for Cancer Therapy. Int J Mol Sci 2020; 21:E3363. [PMID: 32397535 PMCID: PMC7247703 DOI: 10.3390/ijms21093363] [Citation(s) in RCA: 134] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/30/2020] [Accepted: 05/06/2020] [Indexed: 12/14/2022] Open
Abstract
Mitochondria are well known for their role in ATP production and biosynthesis of macromolecules. Importantly, increasing experimental evidence points to the roles of mitochondrial bioenergetics, dynamics, and signaling in tumorigenesis. Recent studies have shown that many types of cancer cells, including metastatic tumor cells, therapy-resistant tumor cells, and cancer stem cells, are reliant on mitochondrial respiration, and upregulate oxidative phosphorylation (OXPHOS) activity to fuel tumorigenesis. Mitochondrial metabolism is crucial for tumor proliferation, tumor survival, and metastasis. Mitochondrial OXPHOS dependency of cancer has been shown to underlie the development of resistance to chemotherapy and radiotherapy. Furthermore, recent studies have demonstrated that elevated heme synthesis and uptake leads to intensified mitochondrial respiration and ATP generation, thereby promoting tumorigenic functions in non-small cell lung cancer (NSCLC) cells. Also, lowering heme uptake/synthesis inhibits mitochondrial OXPHOS and effectively reduces oxygen consumption, thereby inhibiting cancer cell proliferation, migration, and tumor growth in NSCLC. Besides metabolic changes, mitochondrial dynamics such as fission and fusion are also altered in cancer cells. These alterations render mitochondria a vulnerable target for cancer therapy. This review summarizes recent advances in the understanding of mitochondrial alterations in cancer cells that contribute to tumorigenesis and the development of drug resistance. It highlights novel approaches involving mitochondria targeting in cancer therapy.
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Stotland AB, Spivia W, Orosco A, Andres AM, Gottlieb RA, Van Eyk JE, Parker SJ. MitoPlex: A targeted multiple reaction monitoring assay for quantification of a curated set of mitochondrial proteins. J Mol Cell Cardiol 2020; 142:1-13. [PMID: 32234390 PMCID: PMC7347090 DOI: 10.1016/j.yjmcc.2020.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 12/21/2022]
Abstract
Mitochondria are the major source of cellular energy (ATP), as well as critical mediators of widespread functions such as cellular redox balance, apoptosis, and metabolic flux. The organelles play an especially important role in the maintenance of cardiac homeostasis; their inability to generate ATP following impairment due to ischemic damage has been directly linked to organ failure. Methods to quantify mitochondrial content are limited to low throughput immunoassays, measurement of mitochondrial DNA, or relative quantification by untargeted mass spectrometry. Here, we present a high throughput, reproducible and quantitative mass spectrometry multiple reaction monitoring based assay of 37 proteins critical to central carbon chain metabolism and overall mitochondrial function termed 'MitoPlex'. We coupled this protein multiplex with a parallel analysis of the central carbon chain metabolites (219 metabolite assay) extracted in tandem from the same sample, be it cells or tissue. In tests of its biological applicability in cells and tissues, "MitoPlex plus metabolites" indicated profound effects of HMG-CoA Reductase inhibition (e.g., statin treatment) on mitochondria of i) differentiating C2C12 skeletal myoblasts, as well as a clear opposite trend of statins to promote mitochondrial protein expression and metabolism in heart and liver, while suppressing mitochondrial protein and ii) aspects of metabolism in the skeletal muscle obtained from C57Bl6 mice. Our results not only reveal new insights into the metabolic effect of statins in skeletal muscle, but present a new high throughput, reliable MS-based tool to study mitochondrial dynamics in both cell culture and in vivo models.
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Fu A, Alvarez-Perez JC, Avizonis D, Kin T, Ficarro SB, Choi DW, Karakose E, Badur MG, Evans L, Rosselot C, Bridon G, Bird GH, Seo HS, Dhe-Paganon S, Kamphorst JJ, Stewart AF, James Shapiro AM, Marto JA, Walensky LD, Jones RG, Garcia-Ocana A, Danial NN. Glucose-dependent partitioning of arginine to the urea cycle protects β-cells from inflammation. Nat Metab 2020; 2:432-446. [PMID: 32694660 PMCID: PMC7568475 DOI: 10.1038/s42255-020-0199-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 03/26/2020] [Indexed: 02/07/2023]
Abstract
Chronic inflammation is linked to diverse disease processes, but the intrinsic mechanisms that determine cellular sensitivity to inflammation are incompletely understood. Here, we show the contribution of glucose metabolism to inflammation-induced changes in the survival of pancreatic islet β-cells. Using metabolomic, biochemical and functional analyses, we investigate the protective versus non-protective effects of glucose in the presence of pro-inflammatory cytokines. When protective, glucose metabolism augments anaplerotic input into the TCA cycle via pyruvate carboxylase (PC) activity, leading to increased aspartate levels. This metabolic mechanism supports the argininosuccinate shunt, which fuels ureagenesis from arginine and conversely diminishes arginine utilization for production of nitric oxide (NO), a chief mediator of inflammatory cytotoxicity. Activation of the PC-urea cycle axis is sufficient to suppress NO synthesis and shield cells from death in the context of inflammation and other stress paradigms. Overall, these studies uncover a previously unappreciated link between glucose metabolism and arginine-utilizing pathways via PC-directed ureagenesis as a protective mechanism.
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Ji J, Shi Z, Xie T, Zhang X, Chen W, Du C, Sun J, Yue J, Zhao X, Jiang Z, Shi S. Responses of GABA shunt coupled with carbon and nitrogen metabolism in poplar under NaCl and CdCl 2 stresses. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 193:110322. [PMID: 32109582 DOI: 10.1016/j.ecoenv.2020.110322] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 02/05/2020] [Accepted: 02/08/2020] [Indexed: 05/20/2023]
Abstract
The γ-aminobutyric acid (GABA) shunt is closely associated with plant tolerance; however, little is known about its mechanism. This study aimed to decipher the responses of the GABA shunt and related carbon-nitrogen metabolism in poplar seedlings (Populus alba × Populus glandulosa) treated with different NaCl and CdCl2 concentrations for 30 h. The results showed that the activities of glutamate decarboxylase (GAD) and GABA-transaminase (GABA-T) were activated, as well as α-ketoglutarate dehydrogenase (α-KGDH) and succinate dehydrogenase (SDH) activities were enhanced by NaCl and CdCl2 stresses, except for SDH under CdCl2 stress. Meanwhile, the expression levels of GADs, GABA-Ts SDHs, succinyl-CoA ligases (SCSs), and succinic acid aldehyde dehydrogenases (SSADHs) were also increased. Notably, significant increases in the key components of GABA shunt, Glu and GABA, were observed under both stresses. Soluble sugars and free amino acids were enhanced, whereas citrate, malate and succinate were almost inhibited by both NaCl and CdCl2 stresses except that citrate was not changed or just increased by 50-mM NaCl stress. Thus, these results suggested that the carbon-nitrogen balance could be altered by activating the GABA shunt when main TCA-cycle intermediates were inhibited under NaCl and CdCl2 stresses. This study can enhance the understanding about the functions of the GABA shunt in woody plants under abiotic stresses and may be applied to the genetic improvement of trees for phytoremediation.
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Park KT, Han JK, Kim SJ, Lim YH. Gamma-Aminobutyric Acid Increases Erythropoietin by Activation of Citrate Cycle and Stimulation of Hypoxia-Inducible Factors Expression in Rats. Biomolecules 2020; 10:E595. [PMID: 32290638 PMCID: PMC7226430 DOI: 10.3390/biom10040595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/04/2020] [Accepted: 04/09/2020] [Indexed: 02/07/2023] Open
Abstract
Erythropoietin (EPO) is the primary regulator of erythropoiesis in the mammalian fetus and adult. Deficiency of EPO induces anemia. In this study, we investigated the effect of gamma-aminobutyric acid (GABA) on serum EPO levels and erythropoiesis in rats. Expression levels of Epo-related genes were measured by quantitative real-time PCR (qPCR) and expression of Epo and Epo receptor (Epor) proteins were measured by immunohistochemistry. The gene and protein expression profiles of kidney tissue in GABA-treated rats were evaluated by ribonucleic acid (RNA) sequencing and two-dimensional electrophoresis (2-DE), respectively. GABA significantly increased serum EPO levels and expression levels of Epo and Epor. GABA increased expression levels of hypoxia-inducible factor (Hif)-1 and Hif-2. Seven proteins with expression levels showing >2-fold change were identified by 2-DE followed by MALDI-TOF MS in GABA-treated rat kidney. The top KEGG pathway from the identified proteins was the tricarboxylic acid cycle, and nicotinamide adenine dinucleotide (NADH) dehydrogenase, succinate dehydrogenase, and isocitrate dehydrogenase were identified as key proteins. GABA treatment significantly increased ATP levels and NADH dehydrogenase activity in a dose-dependent manner. In conclusion, GABA shows a new physiological role in EPO production, and it can thus can contribute to the prevention of anemia when used alone or in combination with other anemia treating drugs.
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Khan MA, Zubair H, Anand S, Srivastava SK, Singh S, Singh AP. Dysregulation of metabolic enzymes in tumor and stromal cells: Role in oncogenesis and therapeutic opportunities. Cancer Lett 2020; 473:176-185. [PMID: 31923436 PMCID: PMC7067140 DOI: 10.1016/j.canlet.2020.01.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/12/2019] [Accepted: 01/03/2020] [Indexed: 01/15/2023]
Abstract
Altered cellular metabolism is a hallmark of cancer. Metabolic rewiring in cancer cells occurs due to the activation of oncogenes, inactivation of tumor suppressor genes, and/or other adaptive changes in cell signaling pathways. Furthermore, altered metabolism is also reported in tumor-corrupted stromal cells as a result of their interaction with cancer cells or due to their adaptation in the dynamic tumor microenvironment. Metabolic alterations are associated with dysregulation of metabolic enzymes and tumor-stromal metabolic crosstalk is vital for the progressive malignant journey of the tumor cells. Therefore, several therapies targeting metabolic enzymes have been evaluated and/or are being investigated in preclinical and clinical studies. In this review, we discuss some important metabolic enzymes that are altered in tumor and/or stromal cells, and focus on their role in supporting tumor growth. Moreover, we also discuss studies carried out in various cancers to target these metabolic abnormalities for therapeutic exploitation.
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69
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Justinić I, Katić A, Uršičić D, Ćurko-Cofek B, Blagović B, Čanadi Jurešić G. Combining proteomics and lipid analysis to unravel Confidor stress response in Saccharomyces cerevisiae. ENVIRONMENTAL TOXICOLOGY 2020; 35:346-358. [PMID: 31696623 DOI: 10.1002/tox.22870] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 10/09/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
The yeast Saccharomyces cerevisiae is a useful model for studying the influence of different stress factors on eukaryotic cells. In this work we used the pesticide imidacloprid, in the Confidor formulation, as the stress factor and analyzed its influence on the metabolic activity, proteome and lipid content and composition of Saccharomyces cerevisiae yeast. During the cultivation of yeast, the lowest recommended application dose of Confidor (0.025%, v/v) was added to the growth media and its influence on the mitochondria, cytosol with microsomes, and the whole yeast cells was monitored. The results show that under the stress provoked by the toxic effects of Confidor, yeast cells density significantly decreased and the percentage of metabolically disturbed cells significantly increased comparing with untreated control. Also, there was a downregulation of majority of glycolytic, gluconeogenesis, and TCA cycle enzymes (Fba1, Adh1, Hxk2, Tal1, Tdh1,Tdh3, Eno1) thus providing enough acetyl-CoA for the lipid restructuring and accumulation mechanism since we have found the changes in the cell and mitochondrial lipid content and FA composition. This data suggest that lipids could be the molecules that orchestrate the answer of the cells in the stress response to the Confidor treatment.
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70
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Lu Z, Wang S, Ji C, Li F, Cong M, Shan X, Wu H. iTRAQ-based proteomic analysis on the mitochondrial responses in gill tissues of juvenile olive flounder Paralichthys olivaceus exposed to cadmium. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 257:113591. [PMID: 31744679 DOI: 10.1016/j.envpol.2019.113591] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 10/21/2019] [Accepted: 11/06/2019] [Indexed: 06/10/2023]
Abstract
Cadmium (Cd) is an important heavy metal pollutant in the Bohai Sea. Mitochondria are recognized as the key target for Cd toxicity. However, mitochondrial responses to Cd have not been fully investigated in marine fishes. In this study, the mitochondrial responses were characterized in gills of juvenile flounder Paralichthys olivaceus treated with two environmentally relevant concentrations (5 and 50 μg/L) of Cd for 14 days by determination of mitochondrial membrane potential (MMP), observation of mitochondrial morphology and quantitative proteomic analysis. Both Cd treatments significantly decreased MMPs of mitochondria from flounder gills. Mitochondrial morphologies were altered in Cd-treated flounder samples, indicated by more and smaller mitochondria. iTRAQ-based proteomic analysis indicated that a total of 128 proteins were differentially expressed in both Cd treatments. These proteins were basically involved in various biological processes in gill mitochondria, including mitochondrial morphology and import, tricarboxylic acid (TCA) cycle, oxidative phosphorylation (OXPHOS), primary bile acid biosynthesis, stress resistance and apoptosis. These results indicated that dynamic regulations of energy homeostasis, cholesterol metabolism, stress resistance, apoptosis, and mitochondrial morphology in gill mitochondria might play significant roles in response to Cd toxicity. Overall, this study provided a global view on mitochondrial toxicity of Cd in flounder gills using iTRAQ-based proteomics.
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71
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Che-Othman MH, Jacoby RP, Millar AH, Taylor NL. Wheat mitochondrial respiration shifts from the tricarboxylic acid cycle to the GABA shunt under salt stress. THE NEW PHYTOLOGIST 2020; 225:1166-1180. [PMID: 30688365 DOI: 10.1111/nph.15713] [Citation(s) in RCA: 90] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 01/21/2019] [Indexed: 05/24/2023]
Abstract
Mitochondrial respiration and tricarboxylic acid (TCA) cycle activity are required during salt stress in plants to provide ATP and reductants for adaptive processes such as ion exclusion, compatible solute synthesis and reactive oxygen species (ROS) detoxification. However, there is a poor mechanistic understanding of how salinity affects mitochondrial metabolism, particularly respiratory substrate source. To determine the mechanism of respiratory changes under salt stress in wheat leaves, we conducted an integrated analysis of metabolite content, respiratory rate and targeted protein abundance measurements. Also, we investigated the direct effect of salt on mitochondrial enzyme activities. Salt-treated wheat leaves exhibit higher respiration rate and extensive metabolite changes. The activity of the TCA cycle enzymes pyruvate dehydrogenase complex and the 2-oxoglutarate dehydrogenase complex were shown to be directly salt-sensitive. Multiple lines of evidence showed that the γ-aminobutyric acid (GABA) shunt was activated under salt treatment. During salt exposure, key metabolic enzymes required for the cyclic operation of the TCA cycle are physiochemically inhibited by salt. This inhibition is overcome by increased GABA shunt activity, which provides an alternative carbon source for mitochondria that bypasses salt-sensitive enzymes, to facilitate the increased respiration of wheat leaves.
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Kaymak I, Maier CR, Schmitz W, Campbell AD, Dankworth B, Ade CP, Walz S, Paauwe M, Kalogirou C, Marouf H, Rosenfeldt MT, Gay DM, McGregor GH, Sansom OJ, Schulze A. Mevalonate Pathway Provides Ubiquinone to Maintain Pyrimidine Synthesis and Survival in p53-Deficient Cancer Cells Exposed to Metabolic Stress. Cancer Res 2020; 80:189-203. [PMID: 31744820 DOI: 10.1158/0008-5472.can-19-0650] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 10/01/2019] [Accepted: 11/14/2019] [Indexed: 11/16/2022]
Abstract
Oncogene activation and loss of tumor suppressor function changes the metabolic activity of cancer cells to drive unrestricted proliferation. Moreover, cancer cells adapt their metabolism to sustain growth and survival when access to oxygen and nutrients is restricted, such as in poorly vascularized tumor areas. We show here that p53-deficient colon cancer cells exposed to tumor-like metabolic stress in spheroid culture activated the mevalonate pathway to promote the synthesis of ubiquinone. This was essential to maintain mitochondrial electron transport for respiration and pyrimidine synthesis in metabolically compromised environments. Induction of mevalonate pathway enzyme expression in the absence of p53 was mediated by accumulation and stabilization of mature SREBP2. Mevalonate pathway inhibition by statins blocked pyrimidine nucleotide biosynthesis and induced oxidative stress and apoptosis in p53-deficient cancer cells in spheroid culture. Moreover, ubiquinone produced by the mevalonate pathway was essential for the growth of p53-deficient tumor organoids. In contrast, inhibition of intestinal hyperproliferation by statins in an Apc/KrasG12D-mutant mouse model was independent of de novo pyrimidine synthesis. Our results highlight the importance of the mevalonate pathway for maintaining mitochondrial electron transfer and biosynthetic activity in cancer cells exposed to metabolic stress. They also demonstrate that the metabolic output of this pathway depends on both genetic and environmental context. SIGNIFICANCE: These findings suggest that p53-deficient cancer cells activate the mevalonate pathway via SREBP2 and promote the synthesis of ubiquinone that plays an essential role in reducing oxidative stress and supports the synthesis of pyrimidine nucleotide.
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73
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Huangyang P, Li F, Lee P, Nissim I, Weljie AM, Mancuso A, Li B, Keith B, Yoon SS, Simon MC. Fructose-1,6-Bisphosphatase 2 Inhibits Sarcoma Progression by Restraining Mitochondrial Biogenesis. Cell Metab 2020; 31:174-188.e7. [PMID: 31761563 PMCID: PMC6949384 DOI: 10.1016/j.cmet.2019.10.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 08/22/2019] [Accepted: 10/23/2019] [Indexed: 12/19/2022]
Abstract
The remarkable cellular and genetic heterogeneity of soft tissue sarcomas (STSs) limits the clinical benefit of targeted therapies. Here, we show that expression of the gluconeogenic isozyme fructose-1,6-bisphosphatase 2 (FBP2) is silenced in a broad spectrum of sarcoma subtypes, revealing an apparent common metabolic feature shared by diverse STSs. Enforced FBP2 expression inhibits sarcoma cell and tumor growth through two distinct mechanisms. First, cytosolic FBP2 antagonizes elevated glycolysis associated with the "Warburg effect," thereby inhibiting sarcoma cell proliferation. Second, nuclear-localized FBP2 restrains mitochondrial biogenesis and respiration in a catalytic-activity-independent manner by inhibiting the expression of nuclear respiratory factor and mitochondrial transcription factor A (TFAM). Specifically, nuclear FBP2 colocalizes with the c-Myc transcription factor at the TFAM locus and represses c-Myc-dependent TFAM expression. This unique dual function of FBP2 provides a rationale for its selective suppression in STSs, identifying a potential metabolic vulnerability of this malignancy and possible therapeutic target.
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Smith MR, Chacko BK, Johnson MS, Benavides GA, Uppal K, Go YM, Jones DP, Darley-Usmar VM. A precision medicine approach to defining the impact of doxorubicin on the bioenergetic-metabolite interactome in human platelets. Redox Biol 2020; 28:101311. [PMID: 31546171 PMCID: PMC6812033 DOI: 10.1016/j.redox.2019.101311] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 08/22/2019] [Accepted: 08/30/2019] [Indexed: 12/26/2022] Open
Abstract
Non-invasive measures of the response of individual patients to cancer therapeutics is an emerging strategy in precision medicine. Platelets offer a potential dynamic marker for metabolism and bioenergetic responses in individual patients since they have active glycolysis and mitochondrial oxidative phosphorylation and can be easily isolated from a small blood sample. We have recently shown how the bioenergetic-metabolite interactome can be defined in platelets isolated from human subjects by measuring metabolites and bioenergetics in the same sample. In the present study, we used a model system to assess test the hypothesis that this interactome is modified by xenobiotics using exposure to the anti-cancer drug doxorubicin (Dox) in individual donors. We found that unsupervised analysis of the metabolome showed clear differentiation between the control and Dox treated group. Dox treatment resulted in a concentration-dependent decrease in bioenergetic parameters with maximal respiration being most sensitive and this was associated with significant changes in over 166 features. A metabolome-wide association study of Dox was also conducted, and Dox was found to have associations with metabolites in the glycolytic and TCA cycle pathways. Lastly, network analysis showed the impact of Dox on the bioenergetic-metabolite interactome and revealed profound changes in the regulation of reserve capacity. Taken together, these data support the conclusion that platelets are a suitable platform to predict and monitor therapeutic efficacy as well as anticipate susceptibility to toxicity in the context of precision medicine.
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Leone RD, Zhao L, Englert JM, Sun IM, Oh MH, Sun IH, Arwood ML, Bettencourt IA, Patel CH, Wen J, Tam A, Blosser RL, Prchalova E, Alt J, Rais R, Slusher BS, Powell JD. Glutamine blockade induces divergent metabolic programs to overcome tumor immune evasion. Science 2019; 366:1013-1021. [PMID: 31699883 PMCID: PMC7023461 DOI: 10.1126/science.aav2588] [Citation(s) in RCA: 640] [Impact Index Per Article: 128.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 07/21/2019] [Accepted: 10/25/2019] [Indexed: 12/13/2022]
Abstract
The metabolic characteristics of tumors present considerable hurdles to immune cell function and cancer immunotherapy. Using a glutamine antagonist, we metabolically dismantled the immunosuppressive microenvironment of tumors. We demonstrate that glutamine blockade in tumor-bearing mice suppresses oxidative and glycolytic metabolism of cancer cells, leading to decreased hypoxia, acidosis, and nutrient depletion. By contrast, effector T cells responded to glutamine antagonism by markedly up-regulating oxidative metabolism and adopting a long-lived, highly activated phenotype. These divergent changes in cellular metabolism and programming form the basis for potent antitumor responses. Glutamine antagonism therefore exposes a previously undefined difference in metabolic plasticity between cancer cells and effector T cells that can be exploited as a "metabolic checkpoint" for tumor immunotherapy.
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