bims-mepmim 2022-12-25 papers

bims-mepmim

Biomed News

on Metabolites in pathological microenvironments and immunometabolism

Issue of 2022–12–25
25 papers selected by
Erika Mariana Palmieri, NIH/NCI Laboratory of Cancer ImmunoMetabolism

Saturated very long-chain fatty acids regulate macrophage plasticity and invasiveness.
Dynamic partitioning of branched-chain amino acids-derived nitrogen supports renal cancer progression.
Cholesterol accumulation in macrophages drives NETosis in atherosclerotic plaques via IL-1β secretion.
Acly Deficiency Enhances Myelopoiesis through Acetyl Coenzyme A and Metabolic-Epigenetic Cross-Talk.
Widespread, Reversible Cysteine Modification by Methylglyoxal Regulates Metabolic Enzyme Function.
Effects of osteoblast-derived extracellular vesicles on aggressiveness, redox status and mitochondrial bioenergetics of MNNG/HOS osteosarcoma cells.
mTORC1 regulates a lysosome-dependent adaptive shift in intracellular lipid species.
Type 2 diabetes is associated with increased circulating levels of 3-hydroxydecanoate activating GPR84 and neutrophil migration.
Futile cycle of β-oxidation and de novo lipogenesis are associated with essential fatty acids depletion in lipoatrophy.
Microenvironmental ammonia enhances T cell exhaustion in colorectal cancer.
Kir4.2 mediates proximal potassium effects on glutaminase activity and kidney injury.
Highly expressed SERCA2 triggers tumor cell autophagy and is a druggable vulnerability in triple-negative breast cancer.
PCNA regulates primary metabolism by scaffolding metabolic enzymes.
The Aging Process: A Metabolomics Perspective.
Acute high fat diet impairs macrophage supported intestinal damage resolution.
Iron cycle disruption by heme oxygenase-1 activation leads to a reduced breast cancer cell survival.
A conformation-specific nanobody targeting the nicotinamide mononucleotide-activated state of SARM1.
Refining sugar's involvement in cholesterol synthesis.
ETV3 and ETV6 enable monocyte differentiation into dendritic cells by repressing macrophage fate commitment.
Activated B cells suppress T-cell function through metabolic competition.
scFASTCORMICS: A Contextualization Algorithm to Reconstruct Metabolic Multi-Cell Population Models from Single-Cell RNAseq Data.
Eosinophil-derived IL-4 is necessary to establish the inflammatory structure in innate inflammation.
Extracellular arginine is required but the arginine transporter CAT3 (Slc7a3) is dispensable for mouse normal and malignant hematopoiesis.
Hypoxia drives CD39-dependent suppressor function in exhausted T cells to limit antitumor immunity.
Adipose-targeted triiodothyronine therapy counteracts obesity-related metabolic complications and atherosclerosis with negligible side effects.

J Neuroinflammation. 2022 Dec 17. 19(1): 305

Saturated very long-chain fatty acids regulate macrophage plasticity and invasiveness.

Bettina Zierfuss, Agnieszka Buda, Andrea Villoria-González, Maxime Logist, Jure Fabjan, Patricia Parzer, Claire Battin, Streggi Vandersteene, Inge M E Dijkstra, Petra Waidhofer-Söllner, Katharina Grabmeier-Pfistershammer, Peter Steinberger, Stephan Kemp, Sonja Forss-Petter, Johannes Berger, Isabelle Weinhofer.

  Saturated very long-chain fatty acids (VLCFA, ≥ C22), enriched in brain myelin and innate immune cells, accumulate in X-linked adrenoleukodystrophy (X-ALD) due to inherited dysfunction of the peroxisomal VLCFA transporter ABCD1. In its severest form, X-ALD causes cerebral myelin destruction with infiltration of pro-inflammatory skewed monocytes/macrophages. How VLCFA levels relate to macrophage activation is unclear. Here, whole transcriptome sequencing of X-ALD macrophages indicated that VLCFAs prime human macrophage membranes for inflammation and increased expression of factors involved in chemotaxis and invasion. When added externally to mimic lipid release in demyelinating X-ALD lesions, VLCFAs did not activate toll-like receptors in primary macrophages. In contrast, VLCFAs provoked pro-inflammatory responses through scavenger receptor CD36-mediated uptake, cumulating in JNK signalling and expression of matrix-degrading enzymes and chemokine release. Following pro-inflammatory LPS activation, VLCFA levels increased also in healthy macrophages. With the onset of the resolution, VLCFAs were rapidly cleared in control macrophages by increased peroxisomal VLCFA degradation through liver-X-receptor mediated upregulation of ABCD1. ABCD1 deficiency impaired VLCFA homeostasis and prolonged pro-inflammatory gene expression upon LPS treatment. Our study uncovers a pivotal role for ABCD1, a protein linked to neuroinflammation, and associated peroxisomal VLCFA degradation in regulating macrophage plasticity.

Keywords:  Extracellular matrix degradation; Immune response; Lipid metabolism; Neuroinflammation; X-linked adrenoleukodystrophy

DOI:  https://doi.org/10.1186/s12974-022-02664-y
Nat Commun. 2022 Dec 20. 13(1): 7830

Dynamic partitioning of branched-chain amino acids-derived nitrogen supports renal cancer progression.

Marco Sciacovelli, Aurelien Dugourd, Lorea Valcarcel Jimenez, Ming Yang, Efterpi Nikitopoulou, Ana S H Costa, Laura Tronci, Veronica Caraffini, Paulo Rodrigues, Christina Schmidt, Dylan Gerard Ryan, Timothy Young, Vincent R Zecchini, Sabrina H Rossi, Charlie Massie, Caroline Lohoff, Maria Masid, Vassily Hatzimanikatis, Christoph Kuppe, Alex Von Kriegsheim, Rafael Kramann, Vincent Gnanapragasam, Anne Y Warren, Grant D Stewart, Ayelet Erez, Sakari Vanharanta, Julio Saez-Rodriguez, Christian Frezza.

Metabolic reprogramming is critical for tumor initiation and progression. However, the exact impact of specific metabolic changes on cancer progression is poorly understood. Here, we integrate multimodal analyses of primary and metastatic clonally-related clear cell renal cancer cells (ccRCC) grown in physiological media to identify key stage-specific metabolic vulnerabilities. We show that a VHL loss-dependent reprogramming of branched-chain amino acid catabolism sustains the de novo biosynthesis of aspartate and arginine enabling tumor cells with the flexibility of partitioning the nitrogen of the amino acids depending on their needs. Importantly, we identify the epigenetic reactivation of argininosuccinate synthase (ASS1), a urea cycle enzyme suppressed in primary ccRCC, as a crucial event for metastatic renal cancer cells to acquire the capability to generate arginine, invade in vitro and metastasize in vivo. Overall, our study uncovers a mechanism of metabolic flexibility occurring during ccRCC progression, paving the way for the development of novel stage-specific therapies.

DOI: https://doi.org/10.1038/s41467-022-35036-4
Cardiovasc Res. 2022 Dec 20. pii: cvac189. [Epub ahead of print]

Cholesterol accumulation in macrophages drives NETosis in atherosclerotic plaques via IL-1β secretion.

Mustafa Yalcinkaya, Panagiotis Fotakis, Wenli Liu, Kaori Endo-Umeda, Huijuan Dou, Sandra Abramowicz, Tong Xiao, Peter Libby, Nan Wang, Alan R Tall, Marit Westerterp.

OBJECTIVE: Neutrophil extracellular trap formation (NETosis) increases atherosclerotic plaque vulnerability and athero-thrombosis. However, mechanisms promoting NETosis during atherogenesis are poorly understood. We have shown that cholesterol accumulation due to myeloid cell deficiency of the cholesterol transporters ATP Binding Cassette A1 and G1 (ABCA1/G1) promotes NLRP3 inflammasome activation in macrophages and neutrophils and induces prominent NETosis in atherosclerotic plaques. We investigated whether NETosis is a cell intrinsic effect in neutrophils or is mediated indirectly by cellular crosstalk from macrophages to neutrophils involving IL-1β.
METHODS AND RESULTS: We generated mice with neutrophil or macrophage-specific Abca1/g1 deficiency (S100A8CreAbca1fl/flAbcg1fl/fl or CX3CR1CreAbca1fl/flAbcg1fl/fl mice, respectively), and transplanted their bone marrow into low-density lipoprotein receptor knockout mice. We then fed the mice a cholesterol-rich diet. Macrophage, but not neutrophil Abca1/g1 deficiency activated inflammasomes in macrophages and neutrophils, reflected by caspase-1 cleavage, and induced NETosis in plaques. NETosis was suppressed by administering an interleukin (IL)-1β neutralizing antibody. The extent of NETosis in plaques correlated strongly with the degree of neutrophil accumulation, irrespective of blood neutrophil counts, and neutrophil accumulation was decreased by IL-1β antagonism. In vitro, IL-1β or media transferred from Abca1/g1 deficient macrophages increased NETosis in both control and Abca1/Abcg1 deficient neutrophils. This cell-extrinsic effect of IL-1β on NETosis was blocked by an NLRP3 inhibitor.
CONCLUSIONS: These studies establish a new link between inflammasome mediated IL-1β production in macrophages and NETosis in atherosclerotic plaques. Macrophage-derived IL-1β appears to increase NETosis both by increasing neutrophil recruitment to plaques and by promoting neutrophil NLRP3 inflammasome activation.

DOI: https://doi.org/10.1093/cvr/cvac189
Immunohorizons. 2022 Dec 01. 6(12): 837-850

Acly Deficiency Enhances Myelopoiesis through Acetyl Coenzyme A and Metabolic-Epigenetic Cross-Talk.

Dalton L Greenwood, Haley E Ramsey, Phuong T T Nguyen, Andrew R Patterson, Kelsey Voss, Jackie E Bader, Ayaka Sugiura, Zachary A Bacigalupa, Samuel Schaefer, Xiang Ye, Debolanle O Dahunsi, Matthew Z Madden, Kathryn E Wellen, Michael R Savona, P Brent Ferrell, Jeffrey C Rathmell.

Hematopoiesis integrates cytokine signaling, metabolism, and epigenetic modifications to regulate blood cell generation. These processes are linked, as metabolites provide essential substrates for epigenetic marks. In this study, we demonstrate that ATP citrate lyase (Acly), which metabolizes citrate to generate cytosolic acetyl-CoA and is of clinical interest, can regulate chromatin accessibility to limit myeloid differentiation. Acly was tested for a role in murine hematopoiesis by small-molecule inhibition or genetic deletion in lineage-depleted, c-Kit-enriched hematopoietic stem and progenitor cells from Mus musculus. Treatments increased the abundance of cell populations that expressed the myeloid integrin CD11b and other markers of myeloid differentiation. When single-cell RNA sequencing was performed, we found that Acly inhibitor-treated hematopoietic stem and progenitor cells exhibited greater gene expression signatures for macrophages and enrichment of these populations. Similarly, the single-cell assay for transposase-accessible chromatin sequencing showed increased chromatin accessibility at genes associated with myeloid differentiation, including CD11b, CD11c, and IRF8. Mechanistically, Acly deficiency altered chromatin accessibility and expression of multiple C/EBP family transcription factors known to regulate myeloid differentiation and cell metabolism, with increased Cebpe and decreased Cebpa and Cebpb. This effect of Acly deficiency was accompanied by altered mitochondrial metabolism with decreased mitochondrial polarization but increased mitochondrial content and production of reactive oxygen species. The bias to myeloid differentiation appeared due to insufficient generation of acetyl-CoA, as exogenous acetate to support alternate compensatory pathways to produce acetyl-CoA reversed this phenotype. Acly inhibition thus can promote myelopoiesis through deprivation of acetyl-CoA and altered histone acetylome to regulate C/EBP transcription factor family activity for myeloid differentiation.

DOI: https://doi.org/10.4049/immunohorizons.2200086
ACS Chem Biol. 2022 Dec 23.

Widespread, Reversible Cysteine Modification by Methylglyoxal Regulates Metabolic Enzyme Function.

John S Coukos, Chris W Lee, Kavya S Pillai, Kimberly J Liu, Raymond E Moellering.

Methylglyoxal (MGO), a reactive metabolite byproduct of glucose metabolism, is known to form a variety of posttranslational modifications (PTMs) on nucleophilic amino acids. For example, cysteine, the most nucleophilic proteinogenic amino acid, forms reversible hemithioacetal and stable mercaptomethylimidazole adducts with MGO. The high reactivity of cysteine toward MGO and the rate of formation of such modifications provide the opportunity for mechanisms by which proteins and pathways might rapidly sense and respond to alterations in levels of MGO. This indirect measure of alterations in glycolytic flux would thereby allow disparate cellular processes to dynamically respond to changes in nutrient availability and utilization. Here we report the use of quantitative LC-MS/MS-based chemoproteomic profiling approaches with a cysteine-reactive probe to map the proteome-wide landscape of MGO modification of cysteine residues. This approach led to the identification of many sites of potential functional regulation by MGO. We further characterized the role that such modifications have in a catalytic cysteine residue in a key metabolic enzyme and the resulting effects on cellular metabolism.

DOI: https://doi.org/10.1021/acschembio.2c00727
Front Oncol. 2022 ;12 983254

Effects of osteoblast-derived extracellular vesicles on aggressiveness, redox status and mitochondrial bioenergetics of MNNG/HOS osteosarcoma cells.

Marco Ponzetti, Argia Ucci, Chiara Puri, Luca Giacchi, Irene Flati, Daria Capece, Francesca Zazzeroni, Alfredo Cappariello, Nadia Rucci, Stefano Falone.

  Osteosarcoma is the most common primary bone malignancy. The crosstalk between osteosarcoma and the surrounding tumour microenvironment (TME) drives key events that lead to metastasization, one of the main obstacles for definitive cure of most malignancies. Extracellular vesicles (EVs), lipid bilayer nanoparticles used by cells for intercellular communication, are emerging as critical biological mediators that permit the interplay between neoplasms and the tumour microenvironment, modulating re-wiring of energy metabolism and redox homeostatic processes. We previously showed that EVs derived from the human osteosarcoma cells influence bone cells, including osteoblasts. We here investigated whether the opposite could also be true, studying how osteoblast-derived EVs (OB-EVs) could alter tumour phenotype, mitochondrial energy metabolism, redox status and oxidative damage in MNNG/HOS osteosarcoma cells.These were treated with EVs obtained from mouse primary osteoblasts, and the following endpoints were investigated: i) cell viability and proliferation; ii) apoptosis; iii) migration and invasive capacity; iv) stemness features; v) mitochondrial function and energy metabolism; vi) redox status, antioxidant capacity and oxidative molecular damage. OB-EVs decreased MNNG/HOS metabolic activity and viability, which however was not accompanied by impaired proliferation nor by increased apoptosis, with respect to control. In addition, OB-EV-treated cells exhibited a significant reduction of motility and in vitro invasion as compared to untreated cells. Although the antioxidant N-acetyl-L-cysteine reverted the cytotoxic effect of OB-EVs, no evidence of oxidative stress was observed in treated cells. However, the redox balance of glutathione was significantly shifted towards a pro-oxidant state, even though the major antioxidant enzymatic protection did not respond to the pro-oxidant challenge. We did not find strong evidence of mitochondrial involvement or major energy metabolic switches induced by OB-EVs, but a trend of reduction in seahorse assay basal respiration was observed, suggesting that OB-EVs could represent a mild metabolic challenge for osteosarcoma cells. In summary, our findings suggest that OB-EVs could serve as important means through which TME and osteosarcoma core cross-communicate. For the first time, we proved that OB-EVs reduced osteosarcoma cells' aggressiveness and viability through redox-dependent signalling pathways, even though mitochondrial dynamics and energy metabolism did not appear as processes critically needed to respond to OB-EVs.

Keywords:  apoptosis; bioenergetics; cell communication; extracellular vesicles; mitochondria; osteosarcoma; redox status; tumour microenvironment

DOI:  https://doi.org/10.3389/fonc.2022.983254
Nat Metab. 2022 Dec;4(12): 1792-1811

mTORC1 regulates a lysosome-dependent adaptive shift in intracellular lipid species.

Aaron M Hosios, Meghan E Wilkinson, Molly C McNamara, Krystle C Kalafut, Margaret E Torrence, John M Asara, Brendan D Manning.

The mechanistic target of rapamycin complex 1 (mTORC1) senses and relays environmental signals from growth factors and nutrients to metabolic networks and adaptive cellular systems to control the synthesis and breakdown of macromolecules; however, beyond inducing de novo lipid synthesis, the role of mTORC1 in controlling cellular lipid content remains poorly understood. Here we show that inhibition of mTORC1 via small molecule inhibitors or nutrient deprivation leads to the accumulation of intracellular triglycerides in both cultured cells and a mouse tumor model. The elevated triglyceride pool following mTORC1 inhibition stems from the lysosome-dependent, but autophagy-independent, hydrolysis of phospholipid fatty acids. The liberated fatty acids are available for either triglyceride synthesis or β-oxidation. Distinct from the established role of mTORC1 activation in promoting de novo lipid synthesis, our data indicate that mTORC1 inhibition triggers membrane phospholipid trafficking to the lysosome for catabolism and an adaptive shift in the use of constituent fatty acids for storage or energy production.

DOI: https://doi.org/10.1038/s42255-022-00706-6
iScience. 2022 Dec 22. 25(12): 105683

Type 2 diabetes is associated with increased circulating levels of 3-hydroxydecanoate activating GPR84 and neutrophil migration.

Randi Bonke Mikkelsen, Tulika Arora, Kajetan Trošt, Oksana Dmytriyeva, Sune Kjærsgaard Jensen, Abraham Stijn Meijnikman, Louise Elisabeth Olofsson, Dimitra Lappa, Ömrüm Aydin, Jens Nielsen, Victor Gerdes, Thomas Moritz, Arnold van de Laar, Maurits de Brauw, Max Nieuwdorp, Siv Annegrethe Hjorth, Thue Walter Schwartz, Fredrik Bäckhed.

  Obesity and diabetes are associated with inflammation and altered plasma levels of several metabolites, which may be involved in disease progression. Some metabolites can activate G protein-coupled receptors (GPCRs) expressed on immune cells where they can modulate metabolic inflammation. Here, we find that 3-hydroxydecanoate is enriched in the circulation of obese individuals with type 2 diabetes (T2D) compared with nondiabetic controls. Administration of 3-hydroxydecanoate to mice promotes immune cell recruitment to adipose tissue, which was associated with adipose inflammation and increased fasting insulin levels. Furthermore, we demonstrate that 3-hydroxydecanoate stimulates migration of primary human and mouse neutrophils, but not monocytes, through GPR84 and Gαi signaling in vitro. Our findings indicate that 3-hydroxydecanoate is a T2D-associated metabolite that increases inflammatory responses and may contribute to the chronic inflammation observed in diabetes.

Keywords:  Cell biology; Immunology; Pathophysiology

DOI:  https://doi.org/10.1016/j.isci.2022.105683
Biochim Biophys Acta Mol Cell Biol Lipids. 2022 Dec 17. pii: S1388-1981(22)00154-8. [Epub ahead of print]1868(3): 159264

Futile cycle of β-oxidation and de novo lipogenesis are associated with essential fatty acids depletion in lipoatrophy.

Adriano B Chaves-Filho, Albert S Peixoto, Érique Castro, Tiago E Oliveira, Luiz A Perandini, Rafael J Moreira, Railmara P da Silva, Beatriz P da Silva, Eduardo H Moretti, Alexandre A Steiner, Sayuri Miyamoto, Marcos Y Yoshinaga, William T Festuccia.

  Total absence of adipose tissue (lipoatrophy) is associated with the development of severe metabolic disorders including hepatomegaly and fatty liver. Here, we sought to investigate the impact of severe lipoatrophy induced by deletion of peroxisome proliferator-activated receptor gamma (PPARγ) exclusively in adipocytes on lipid metabolism in mice. Untargeted lipidomics of plasma, gastrocnemius and liver uncovered a systemic depletion of the essential linoleic (LA) and α-linolenic (ALA) fatty acids from several lipid classes (storage lipids, glycerophospholipids, free fatty acids) in lipoatrophic mice. Our data revealed that such essential fatty acid depletion was linked to increased: 1) capacity for liver mitochondrial fatty acid β-oxidation (FAO), 2) citrate synthase activity and coenzyme Q content in the liver, 3) whole-body oxygen consumption and reduced respiratory exchange rate in the dark period, and 4) de novo lipogenesis and carbon flux in the TCA cycle. The key role of de novo lipogenesis in hepatic steatosis was evidenced by an accumulation of stearic, oleic, sapienic and mead acids in liver. Our results thus indicate that the simultaneous activation of the antagonic processes FAO and de novo lipogenesis in liver may create a futile metabolic cycle leading to a preferential depletion of LA and ALA. Noteworthy, this previously unrecognized cycle may also explain the increased energy expenditure displayed by lipoatrophic mice, adding a new piece to the metabolic regulation puzzle in lipoatrophies.

Keywords:  Fatty acid oxidation; Linoleic acid; Lipoatrophy; Peroxisome proliferator-activated receptor gamma (PPARγ); de novo lipogenesis; α-Linolenic acid

DOI:  https://doi.org/10.1016/j.bbalip.2022.159264
Cell Metab. 2022 Dec 12. pii: S1550-4131(22)00504-6. [Epub ahead of print]

Microenvironmental ammonia enhances T cell exhaustion in colorectal cancer.

Hannah N Bell, Amanda K Huber, Rashi Singhal, Navyateja Korimerla, Ryan J Rebernick, Roshan Kumar, Marwa O El-Derany, Peter Sajjakulnukit, Nupur K Das, Samuel A Kerk, Sumeet Solanki, Jadyn G James, Donghwan Kim, Li Zhang, Brandon Chen, Rohit Mehra, Timothy L Frankel, Balázs Győrffy, Eric R Fearon, Marina Pasca di Magliano, Frank J Gonzalez, Ruma Banerjee, Daniel R Wahl, Costas A Lyssiotis, Michael Green, Yatrik M Shah.

  Effective therapies are lacking for patients with advanced colorectal cancer (CRC). The CRC tumor microenvironment has elevated metabolic waste products due to altered metabolism and proximity to the microbiota. The role of metabolite waste in tumor development, progression, and treatment resistance is unclear. We generated an autochthonous metastatic mouse model of CRC and used unbiased multi-omic analyses to reveal a robust accumulation of tumoral ammonia. The high ammonia levels induce T cell metabolic reprogramming, increase exhaustion, and decrease proliferation. CRC patients have increased serum ammonia, and the ammonia-related gene signature correlates with altered T cell response, adverse patient outcomes, and lack of response to immune checkpoint blockade. We demonstrate that enhancing ammonia clearance reactivates T cells, decreases tumor growth, and extends survival. Moreover, decreasing tumor-associated ammonia enhances anti-PD-L1 efficacy. These findings indicate that enhancing ammonia detoxification can reactivate T cells, highlighting a new approach to enhance the efficacy of immunotherapies.

Keywords:  ammonia; cancer metabolism; immunotherapy; tumor microenvironment

DOI:  https://doi.org/10.1016/j.cmet.2022.11.013
Cell Rep. 2022 Dec 20. pii: S2211-1247(22)01732-6. [Epub ahead of print]41(12): 111840

Kir4.2 mediates proximal potassium effects on glutaminase activity and kidney injury.

Andrew S Terker, Yahua Zhang, Juan Pablo Arroyo, Shirong Cao, Suwan Wang, Xiaofeng Fan, Jerod S Denton, Ming-Zhi Zhang, Raymond C Harris.

  Inadequate potassium (K+) consumption correlates with increased mortality and poor cardiovascular outcomes. Potassium effects on blood pressure have been described previously; however, whether or not low K+ independently affects kidney disease progression remains unclear. Here, we demonstrate that dietary K+ deficiency causes direct kidney injury. Effects depend on reduced blood K+ and are kidney specific. In response to reduced K+, the channel Kir4.2 mediates altered proximal tubule (PT) basolateral K+ flux, causing intracellular acidosis and activation of the enzyme glutaminase and the ammoniagenesis pathway. Deletion of either Kir4.2 or glutaminase protects from low-K+ injury. Reduced K+ also mediates injury and fibrosis in a model of aldosteronism. These results demonstrate that the PT epithelium, like the distal nephron, is K+ sensitive, with reduced blood K+ causing direct PT injury. Kir4.2 and glutaminase are essential mediators of this injury process, and we identify their potential for future targeting in the treatment of chronic kidney disease.

Keywords:  CP: Metabolism; Kir4.2; aldosterone; ammoniagenesis; glutaminase; kidney injury; potassium; proximal tubule

DOI:  https://doi.org/10.1016/j.celrep.2022.111840
Acta Pharm Sin B. 2022 Dec;12(12): 4407-4423

Highly expressed SERCA2 triggers tumor cell autophagy and is a druggable vulnerability in triple-negative breast cancer.

Minmin Fan, Jian Gao, Lin Zhou, Wenwen Xue, Yixuan Wang, Jingwei Chen, Wuhao Li, Ying Yu, Bo Liu, Yan Shen, Qiang Xu.

  Chemoresistance remains a major obstacle to successful treatment of triple negative breast cancer (TNBC). Identification of druggable vulnerabilities is an important aim for TNBC therapy. Here, we report that SERCA2 expression correlates with TNBC progression in human patients, which promotes TNBC cell proliferation, migration and chemoresistance. Mechanistically, SERCA2 interacts with LC3B via LIR motif, facilitating WIPI2-independent autophagosome formation to induce autophagy. Autophagy-mediated SERCA2 degradation induces SERCA2 transactivation through a Ca2+/CaMKK/CREB-1 feedback. Moreover, we found that SERCA2-targeting small molecule RL71 enhances SERCA2-LC3B interaction and induces excessive autophagic cell death. The increase in SERCA2 expression predisposes TNBC cells to RL71-induced autophagic cell death in vitro and in vivo. This study elucidates a mechanism by which TNBC cells maintain their high autophagy activity to induce chemoresistance, and suggests increased SERCA2 expression as a druggable vulnerability for TNBC.

Keywords:  Autophagy; Chemoresistance; Druggable; LC3B; SERCA2; TNBC; Vulnerability

DOI:  https://doi.org/10.1016/j.apsb.2022.05.009
Oncogene. 2022 Dec 23.

PCNA regulates primary metabolism by scaffolding metabolic enzymes.

Lisa M Røst, Synnøve B Ræder, Camilla Olaisen, Caroline K Søgaard, Animesh Sharma, Per Bruheim, Marit Otterlei.

The essential roles of proliferating cell nuclear antigen (PCNA) as a scaffold protein in DNA replication and repair are well established, while its cytosolic roles are less explored. Two metabolic enzymes, alpha-enolase (ENO1) and 6-phosphogluconate dehydrogenase (6PGD), both contain PCNA interacting motifs. Mutation of the PCNA interacting motif APIM in ENO1 (F423A) impaired its binding to PCNA and resulted in reduced cellular levels of ENO1 protein, reduced growth rate, reduced glucose consumption, and reduced activation of AKT. Metabolome and signalome analysis reveal large consequences of impairing the direct interaction between PCNA and ENO1. Metabolites above ENO1 in glycolysis accumulated while lower glycolytic and TCA cycle metabolite pools decreased in the APIM-mutated cells; however, their overall energetic status were similar to parental cells. Treating haematological cancer cells or activated primary monocytes with a PCNA targeting peptide drug containing APIM (ATX-101) also lead to a metabolic shift characterized by reduced glycolytic rate. In addition, we show that ATX-101 treatments reduced the ENO1 - PCNA interaction, the ENO1, GAPDH and 6PGD protein levels, as well as the 6PGD activity. Here we report for the first time that PCNA acts as a scaffold for metabolic enzymes, and thereby act as a direct regulator of primary metabolism.

DOI: https://doi.org/10.1038/s41388-022-02579-1
Molecules. 2022 Dec 07. pii: 8656. [Epub ahead of print]27(24):

The Aging Process: A Metabolomics Perspective.

Alex Castro, Étore F Signini, Juliana Magalhães De Oliveira, Maria Carolina Bezerra Di Medeiros Leal, Patrícia Rehder-Santos, Juliana C Millan-Mattos, Vinicius Minatel, Camila B F Pantoni, Regina V Oliveira, Aparecida M Catai, Antônio G Ferreira.

  Aging process is characterized by a progressive decline of several organic, physiological, and metabolic functions whose precise mechanism remains unclear. Metabolomics allows the identification of several metabolites and may contribute to clarifying the aging-regulated metabolic pathways. We aimed to investigate aging-related serum metabolic changes using a metabolomics approach. Fasting blood serum samples from 138 apparently healthy individuals (20-70 years old, 56% men) were analyzed by Proton Nuclear Magnetic Resonance spectroscopy (1H NMR) and Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS), and for clinical markers. Associations of the metabolic profile with age were explored via Correlations (r); Metabolite Set Enrichment Analysis; Multiple Linear Regression; and Aging Metabolism Breakpoint. The age increase was positively correlated (0.212 ≤ r ≤ 0.370, p < 0.05) with the clinical markers (total cholesterol, HDL, LDL, VLDL, triacylglyceride, and glucose levels); negatively correlated (-0.285 ≤ r ≤ -0.214, p < 0.05) with tryptophan, 3-hydroxyisobutyrate, asparagine, isoleucine, leucine, and valine levels, but positively (0.237 ≤ r ≤ 0.269, p < 0.05) with aspartate and ornithine levels. These metabolites resulted in three enriched pathways: valine, leucine, and isoleucine degradation, urea cycle, and ammonia recycling. Additionally, serum metabolic levels of 3-hydroxyisobutyrate, isoleucine, aspartate, and ornithine explained 27.3% of the age variation, with the aging metabolism breakpoint occurring after the third decade of life. These results indicate that the aging process is potentially associated with reduced serum branched-chain amino acid levels (especially after the third decade of life) and progressively increased levels of serum metabolites indicative of the urea cycle.

Keywords:  liquid chromatography-high-resolution mass spectrometry; metabolism; metabolome; nuclear magnetic resonance

DOI:  https://doi.org/10.3390/molecules27248656
JCI Insight. 2022 Dec 20. pii: e164489. [Epub ahead of print]

Acute high fat diet impairs macrophage supported intestinal damage resolution.

Andrea A Hill, Myunghoo Kim, Daniel F Zegarra-Ruiz, Lin-Chun Chang, Kendra C Norwood, Adrien Assié, Wan-Jung H Wu, Michael C Renfroe, Hyo W Song, Angela M Major, Buck S Samuel, Joseph M Hyser, Randy S Longman, Gretchen E Diehl.

  Chronic exposure to high-fat diets (HFD) worsens intestinal disease pathology, but acute effects of HFD in tissue damage remain unclear. Here, we used short-term HFD feeding in a model of intestinal injury and found sustained damage with increased cecal dead neutrophil accumulation, along with dietary lipid accumulation. Neutrophil depletion rescued enhanced pathology. Macrophages from HFD treated mice showed reduced capacity to engulf dead neutrophils. Macrophage clearance of dead neutrophils activates critical barrier repair and anti-inflammatory pathways including IL10, which was lost after acute HFD feeding and intestinal injury. IL10 overexpression restored intestinal repair after HFD feeding and intestinal injury. Macrophage exposure to lipids from the HFD prevented tethering and uptake of apoptotic cells and Il10 induction. Milk fat globule-EGF factor-8 (MFGE8) is a bridging molecule that facilitates macrophage uptake of dead cells. MFGE8 also facilitates lipid uptake, and we demonstrate that dietary lipids interfere with MFGE8-mediated macrophage apoptotic neutrophil uptake and subsequent Il10 production. Our findings demonstrate that HFD promotes intestinal pathology by interfering with macrophage clearance of dead neutrophils, leading to unresolved tissue damage.

Keywords:  Immunology; Macrophages; Neutrophils

DOI:  https://doi.org/10.1172/jci.insight.164489
Biochim Biophys Acta Mol Basis Dis. 2022 Dec 17. pii: S0925-4439(22)00292-7. [Epub ahead of print] 166621

Iron cycle disruption by heme oxygenase-1 activation leads to a reduced breast cancer cell survival.

G Giorgi, M Mascaró, N A Gandini, M E Rabassa, G P Coló, J Arévalo, A C Curino, M M Facchinetti, M E Roque.

  Heme oxygenase-1 (HO-1), which catalyzes heme degradation releasing iron, regulates several processes related to breast cancer. Iron metabolism deregulation is also connected with several tumor processes. However the regulatory relationship between HO-1 and iron proteins in breast cancer remains unclear. Using human breast cancer biopsies, we found that high HO-1 levels significantly correlated with low DMT1 levels. Contrariwise, high HO-1 levels significantly correlated with high ZIP14 and prohepcidin expression, as well as hemosiderin storage. At mRNA level, we found that high HO-1 expression significantly correlated with low DMT1 expression but high ZIP14, L-ferritin and hepcidin expression. In In vivo experiments in mice with genetic overexpression or pharmacological activation of HO-1, we detected the same expression pattern observed in human biopsies. In In vitro experiments, HO-1 activation induced changes in iron proteins expression leading to an increase of hemosiderin, ROS levels, lipid peroxidation and a decrease of the growth rate. Such low growth rate induced by HO-1 activation was reversed when iron levels or ROS levels were reduced. Our findings demonstrate an important role of HO-1 on iron homeostasis in breast cancer. The changes in iron proteins expression when HO-1 is modulated led to the iron accumulation deregulating the iron cell cycle, and consequently, generating oxidative stress and low viability, all contributing to impair breast cancer progression.

Keywords:  Breast cancer; Heme oxygenase-1; Iron cycle; Iron importer; Oxidative stress

DOI:  https://doi.org/10.1016/j.bbadis.2022.166621
Nat Commun. 2022 Dec 22. 13(1): 7898

A conformation-specific nanobody targeting the nicotinamide mononucleotide-activated state of SARM1.

Yun Nan Hou, Yang Cai, Wan Hua Li, Wei Ming He, Zhi Ying Zhao, Wen Jie Zhu, Qiang Wang, Xinyi Mai, Jun Liu, Hon Cheung Lee, Goran Stjepanovic, Hongmin Zhang, Yong Juan Zhao.

Sterile alpha (SAM) and Toll/interleukin-1 receptor (TIR) motif containing 1 (SARM1) is an autoinhibitory NAD-consuming enzyme that is activated by the accumulation of nicotinamide mononucleotide (NMN) during axonal injury. Its activation mechanism is not fully understood. Here, we generate a nanobody, Nb-C6, that specifically recognizes NMN-activated SARM1. Nb-C6 stains only the activated SARM1 in cells stimulated with CZ-48, a permeant mimetic of NMN, and partially activates SARM1 in vitro and in cells. Cryo-EM of NMN/SARM1/Nb-C6 complex shows an octameric structure with ARM domains bending significantly inward and swinging out together with TIR domains. Nb-C6 binds to SAM domain of the activated SARM1 and stabilized its ARM domain. Mass spectrometry analyses indicate that the activated SARM1 in solution is highly dynamic and that the neighboring TIRs form transient dimers via the surface close to one BB loop. We show that Nb-C6 is a valuable tool for studies of SARM1 activation.

DOI: https://doi.org/10.1038/s41467-022-35581-y
Biochim Biophys Acta Mol Cell Biol Lipids. 2022 Dec 14. pii: S1388-1981(22)00156-1. [Epub ahead of print]1868(3): 159266

Refining sugar's involvement in cholesterol synthesis.

Nicole M Fenton, Tina B Nguyen, Laura J Sharpe, Andrew J Brown.

  Glucose metabolism and cholesterol synthesis are often regarded in isolation. Increasing evidence not only links these pathways but also suggests glucose catabolism regulates cholesterol synthesis. Uptake of glucose increases cholesterol production. However, the precise mechanism by which this occurs is not fully understood and is likely to involve many aspects of cellular pathways participating in energy sensing, cholesterol regulation, and synthesis. Here, we review some interesting links between cholesterol synthesis and glucose metabolism. Given glucose breakdown produces energy (both via glycolysis and its products through oxidative phosphorylation), and considering cholesterol synthesis is an energetically demanding process, it would seem logical that glucose metabolism impacts cholesterol synthesis. The energy sensing kinase AMPK carefully monitors energy supply to induce or suppress cholesterol synthesis as needed. Akt, activated by the insulin signalling cascade, regulates key transcription factors involved in lipid metabolism. The insulin signalling pathway also activates machinery involved in the deubiquitination of a key cholesterol synthesis enzyme. Moreover, glucose metabolites, acetyl-CoA, and GlcNAc are substrates for protein acetylation and N-glycosylation, respectively, and can stabilise proteins involved in cholesterol synthesis. As glucose and cholesterol dysregulation are both associated with numerous diseases, understanding the mechanisms of how glucose metabolism and cholesterol synthesis intersect may offer new avenues for therapeutics that make use of these findings.

Keywords:  AMPK; Acetylation; Akt; Cholesterol synthesis; Glucose uptake; Ubiquitination

DOI:  https://doi.org/10.1016/j.bbalip.2022.159266
Nat Immunol. 2022 Dec 21.

ETV3 and ETV6 enable monocyte differentiation into dendritic cells by repressing macrophage fate commitment.

Javiera Villar, Adeline Cros, Alba De Juan, Lamine Alaoui, Pierre-Emmanuel Bonte, Colleen M Lau, Ioanna Tiniakou, Boris Reizis, Elodie Segura.

In inflamed tissues, monocytes differentiate into macrophages (mo-Macs) or dendritic cells (mo-DCs). In chronic nonresolving inflammation, mo-DCs are major drivers of pathogenic events. Manipulating monocyte differentiation would therefore be an attractive therapeutic strategy. However, how the balance of mo-DC versus mo-Mac fate commitment is regulated is not clear. In the present study, we show that the transcriptional repressors ETV3 and ETV6 control human monocyte differentiation into mo-DCs. ETV3 and ETV6 inhibit interferon (IFN)-stimulated genes; however, their action on monocyte differentiation is independent of IFN signaling. Instead, we find that ETV3 and ETV6 directly repress mo-Mac development by controlling MAFB expression. Mice deficient for Etv6 in monocytes have spontaneous expression of IFN-stimulated genes, confirming that Etv6 regulates IFN responses in vivo. Furthermore, these mice have impaired mo-DC differentiation during inflammation and reduced pathology in an experimental autoimmune encephalomyelitis model. These findings provide information about the molecular control of monocyte fate decision and identify ETV6 as a therapeutic target to redirect monocyte differentiation in inflammatory disorders.

DOI: https://doi.org/10.1038/s41590-022-01374-0
J Immunother Cancer. 2022 Dec;pii: e005644. [Epub ahead of print]10(12):

Activated B cells suppress T-cell function through metabolic competition.

Nobuhiko Imahashi, Rafet Basar, Yuefan Huang, Fang Wang, Natalia Baran, Pinaki Prosad Banerjee, Junjun Lu, Ana Karen Nunez Cortes, Nadima Uprety, Emily Ensley, Luis Muniz-Feliciano, Tamara J Laskowski, Judy S Moyes, May Daher, Mayela Mendt, Lucila N Kerbauy, Mayra Shanley, Li Li, Francesca Lorraine Wei Inng Lim, Hila Shaim, Ye Li, Marina Konopleva, Michael Green, Jennifer Wargo, Elizabeth J Shpall, Ken Chen, Katayoun Rezvani.

   BACKGROUND: B cells play a pivotal role in regulating the immune response. The induction of B cell-mediated immunosuppressive function requires B cell activating signals. However, the mechanisms by which activated B cells mediate T-cell suppression are not fully understood.
METHODS: We investigated the potential contribution of metabolic activity of activated B cells to T-cell suppression by performing in vitro experiments and by analyzing clinical samples using mass cytometry and single-cell RNA sequencing.
RESULTS: Here we show that following activation, B cells acquire an immunoregulatory phenotype and promote T-cell suppression by metabolic competition. Activated B cells induced hypoxia in T cells in a cell-cell contact dependent manner by consuming more oxygen via an increase in their oxidative phosphorylation (OXPHOS). Moreover, activated B cells deprived T cells of glucose and produced lactic acid through their high glycolytic activity. Activated B cells thus inhibited the mammalian target of rapamycin pathway in T cells, resulting in suppression of T-cell cytokine production and proliferation. Finally, we confirmed the presence of tumor-associated B cells with high glycolytic and OXPHOS activities in patients with melanoma, associated with poor response to immune checkpoint blockade therapy.
CONCLUSIONS: We have revealed for the first time the immunomodulatory effects of the metabolic activity of activated B cells and their possible role in suppressing antitumor T-cell responses. These findings add novel insights into immunometabolism and have important implications for cancer immunotherapy.

Keywords:  B-lymphocytes; T-lymphocytes; immunomodulation; immunotherapy; melanoma

DOI:  https://doi.org/10.1136/jitc-2022-005644
Metabolites. 2022 Dec 02. pii: 1211. [Epub ahead of print]12(12):

scFASTCORMICS: A Contextualization Algorithm to Reconstruct Metabolic Multi-Cell Population Models from Single-Cell RNAseq Data.

Maria Pires Pacheco, Jimmy Ji, Tessy Prohaska, María Moscardó García, Thomas Sauter.

  Tumours are composed of various cancer cell populations with different mutation profiles, phenotypes and metabolism that cause them to react to drugs in diverse manners. Increasing the resolution of metabolic models based on single-cell expression data will provide deeper insight into such metabolic differences and improve the predictive power of the models. scFASTCORMICS is a network contextualization algorithm that builds multi-cell population genome-scale models from single-cell RNAseq data. The models contain a subnetwork for each cell population in a tumour, allowing to capture metabolic variations between these clusters. The subnetworks are connected by a union compartment that permits to simulate metabolite exchanges between cell populations in the microenvironment. scFASTCORMICS uses Pareto optimization to simultaneously maximise the compactness, completeness and specificity of the reconstructed metabolic models. scFASTCORMICS is implemented in MATLAB and requires the installation of the COBRA toolbox, rFASTCORMICS and the IBM CPLEX solver.

Keywords:  algorithm; metabolic modelling; metabolism; single-cell RNAseq

DOI:  https://doi.org/10.3390/metabo12121211
EMBO Mol Med. 2022 Dec 21. e16796

Eosinophil-derived IL-4 is necessary to establish the inflammatory structure in innate inflammation.

Anja Kolbinger, Tim J Schäufele, Hanna Steigerwald, Joschua Friedel, Sandra Pierre, Gerd Geisslinger, Klaus Scholich.

  Pathogen-induced inflammation comprises pro- and anti-inflammatory processes, which ensure pathogen removal and containment of the proinflammatory activities. Here, we aimed to identify the development of inflammatory microenvironments and their maintenance throughout the course of a toll-like receptor 2-mediated paw inflammation. Within 24 h after pathogen-injection, the immune cells were organized in three zones, which comprised a pathogen-containing "core-region", a bordering proinflammatory (PI)-region and an outer anti-inflammatory (AI)-region. Eosinophils were present in all three inflammatory regions and adapted their cytokine profile according to their localization. Eosinophil depletion reduced IL-4 levels and increased edema formation as well as mechanical and thermal hypersensitivities during resolution of inflammation. Also, in the absence of eosinophils PI- and AI-regions could not be determined anymore, neutrophil numbers increased, and efferocytosis as well as M2-macrophage polarization were reduced. IL-4 administration restored in eosinophil-depleted mice PI- and AI-regions, normalized neutrophil numbers, efferocytosis, M2-macrophage polarization as well as resolution of zymosan-induced hypersensitivity. In conclusion, IL-4-expressing eosinophils support the resolution of inflammation by enabling the development of an anti-inflammatory framework, which encloses proinflammatory regions.

Keywords:  eosinophil; innate inflammation; interleukin-4; macrophages; microenvironments

DOI:  https://doi.org/10.15252/emmm.202216796
Sci Rep. 2022 Dec 17. 12(1): 21832

Extracellular arginine is required but the arginine transporter CAT3 (Slc7a3) is dispensable for mouse normal and malignant hematopoiesis.

Yuhan Yan, Chao Chen, Zhiguo Li, Jing Zhang, Narin Park, Cheng-Kui Qu.

Amino acid-mediated metabolism is one of the key catabolic and anabolic processes involved in diverse cellular functions. However, the role of the semi-essential amino acid arginine in normal and malignant hematopoietic cell development is poorly understood. Here we report that a continuous supply of exogenous arginine is required for the maintenance/function of normal hematopoietic stem cells (HSCs). Surprisingly, knockout of Slc7a3 (CAT3), a major L-arginine transporter, does not affect HSCs in steady-state or under stress. Although Slc7a3 is highly expressed in naïve and activated CD8 T cells, neither T cell development nor activation/proliferation is impacted by Slc7a3 depletion. Furthermore, the Slc7a3 deletion does not attenuate leukemia development driven by Pten loss or the oncogenic Ptpn11E76K mutation. Arginine uptake assays reveal that L-arginine uptake is not disrupted in Slc7a3 knockout cells. These data suggest that extracellular arginine is critically important for HSCs, but CAT3 is dispensable for normal hematopoiesis and leukemogenesis.

DOI: https://doi.org/10.1038/s41598-022-24554-2
Nat Immunol. 2022 Dec 21.

Hypoxia drives CD39-dependent suppressor function in exhausted T cells to limit antitumor immunity.

Paolo D A Vignali, Kristin DePeaux, McLane J Watson, Chenxian Ye, B Rhodes Ford, Konstantinos Lontos, Nicole K McGaa, Nicole E Scharping, Ashley V Menk, Simon C Robson, Amanda C Poholek, Dayana B Rivadeneira, Greg M Delgoffe.

CD8+ T cells are critical for elimination of cancer cells. Factors within the tumor microenvironment (TME) can drive these cells to a hypofunctional state known as exhaustion. The most terminally exhausted T (tTex) cells are resistant to checkpoint blockade immunotherapy and might instead limit immunotherapeutic efficacy. Here we show that intratumoral CD8+ tTex cells possess transcriptional features of CD4+Foxp3+ regulatory T cells and are similarly capable of directly suppressing T cell proliferation ex vivo. tTex cell suppression requires CD39, which generates immunosuppressive adenosine. Restricted deletion of CD39 in endogenous CD8+ T cells resulted in slowed tumor progression, improved immunotherapy responsiveness and enhanced infiltration of transferred tumor-specific T cells. CD39 is induced on tTex cells by tumor hypoxia, thus mitigation of hypoxia limits tTex suppression. Together, these data suggest tTex cells are an important regulatory population in cancer and strategies to limit their generation, reprogram their immunosuppressive state or remove them from the TME might potentiate immunotherapy.

DOI: https://doi.org/10.1038/s41590-022-01379-9
Nat Commun. 2022 Dec 20. 13(1): 7838

Adipose-targeted triiodothyronine therapy counteracts obesity-related metabolic complications and atherosclerosis with negligible side effects.

Kang Chen, Lai Yee Cheong, Yuan Gao, Yaming Zhang, Tianshi Feng, Qin Wang, Leigang Jin, Eric Honoré, Karen S L Lam, Weiping Wang, Xiaoyan Hui, Aimin Xu.

Thyroid hormone (TH) is a thermogenic activator with anti-obesity potential. However, systemic TH administration has no obvious clinical benefits on weight reduction. Herein we selectively delivered triiodothyronine (T3) to adipose tissues by encapsulating T3 in liposomes modified with an adipose homing peptide (PLT3). Systemic T3 administration failed to promote thermogenesis in brown and white adipose tissues (WAT) due to a feedback suppression of sympathetic innervation. PLT3 therapy effectively obviated this feedback suppression on adrenergic inputs, and potently induced browning and thermogenesis of WAT, leading to alleviation of obesity, glucose intolerance, insulin resistance, and fatty liver in obese mice. Furthermore, PLT3 was much more effective than systemic T3 therapy in reducing hypercholesterolemia and atherosclerosis in apoE-deficient mice. These findings uncover WAT as a viable target mediating the therapeutic benefits of TH and provide a safe and efficient therapeutic strategy for obesity and its complications by delivering TH to adipose tissue.

DOI: https://doi.org/10.1038/s41467-022-35470-4