bims-glucam 2024-10-13 papers

bims-glucam

Biomed News

on Glutamine cancer metabolism

Issue of 2024–10–13
thirteen papers selected by
Sreeparna Banerjee, Middle East Technical University

Glutamine Oxidation in Mouse Dorsal Root Ganglia Regulates Pain Resolution and Chronification.
Identification of a novel prognostic model for gastric cancer utilizing glutamine-related genes.
Benzo(a)anthracene Targeting SLC1A5 to Synergistically Enhance PAH Mixture Toxicity.
Combination of low glucose and SCD1 inhibition impairs cancer metabolic plasticity and growth in MCF-7 cancer cells: a comprehensive metabolomic and lipidomic analysis.
Metabolic energetic adaptation of Atlantic salmon phagocytes to changes in carbon sources and exposure to PAMPs.
Metabolism and macrophages in the tumor microenvironment.
Impact of Glutamine-Enhanced Parenteral Nutrition on Postoperative Outcomes in Colorectal Cancer Patients.
Serum metabolome alterations in hyperhomocysteinemia based on targeted and non-targeted MS-platforms.
Exploiting phenotypic heterogeneity to improve production of glutathione by yeast.
Dietary glutamine supplementation improves both Th1 and Th17 responses via CARD11-mTORC1 pathway in murine model of atopic dermatitis.
Single cell atlas reveals multilayered metabolic heterogeneity across tumour types.
Glutamine synthetase accelerates re-endothelialization of vascular grafts by mitigating endothelial cell dysfunction in a rat model.
GLUT1 overexpression in CAR-T cells induces metabolic reprogramming and enhances potency.

J Neurosci. 2024 Oct 08. pii: e1442242024. [Epub ahead of print]

Glutamine Oxidation in Mouse Dorsal Root Ganglia Regulates Pain Resolution and Chronification.

Md Mamunul Haque, Panjamurthy Kuppusamy, Ohannes K Melemedjian.

Chronic pain remains a significant health challenge with limited effective treatments. This study investigates the metabolic changes underlying pain progression and resolution, uncovering a novel compensatory mechanism in sensory neurons. Using the hyperalgesic priming model in male mice, we demonstrate that nerve growth factor (NGF) initially disrupted mitochondrial pyruvate oxidation, leading to acute allodynia. Surprisingly, this metabolic disruption persisted even after the apparent resolution of allodynia. We discovered that during the resolution phase, sensory neurons exhibit increased glutamine oxidation and upregulation of the major glutamine transporter ASCT2 in dorsal root ganglia (DRGs). This compensatory response plays a crucial role in pain resolution, as demonstrated by our experiments. Knockdown of ASCT2 prevents the resolution of NGF-induced allodynia and precipitates the transition to a chronic state. Furthermore, we show that the glutamine catabolite α-ketoglutarate attenuated glycolytic flux and alleviated allodynia in both acute and chronic phases of the hyperalgesic priming model. The importance of ASCT2 is further confirmed in a translational model, where its knockdown prevented the resolution of allodynia following plantar incision. These findings highlight the pivotal role of metabolic changes in pain resolution and identify ASCT2-mediated glutamine metabolism as a potential therapeutic target for chronic pain. Understanding these endogenous mechanisms that promote pain resolution can guide the development of novel interventions to prevent the transition pain from acute to chronic.Significance Statement Chronic pain is a widespread health issue with limited effective treatments. This study unveils a critical metabolic mechanism in sensory neurons that determines whether acute pain resolves or becomes chronic. We discovered that pain resolution depends on a compensatory increase in glutamine metabolism, mediated by the transporter ASCT2, rather than normalization of initial metabolic disruptions. This finding significantly advances our understanding of pain chronification and identifies a novel therapeutic target. By elucidating how the body naturally resolves pain, we open new avenues for developing treatments that could prevent acute pain from transitioning to chronic pain or treat existing chronic pain. This research has the potential to transform pain management strategies and improve quality of life for millions of pain sufferers.

DOI: https://doi.org/10.1523/JNEUROSCI.1442-24.2024
Heliyon. 2024 Oct 15. 10(19): e37985

Identification of a novel prognostic model for gastric cancer utilizing glutamine-related genes.

Weidong Li, Qixing Zhong, Naisheng Deng, Haitao Wang, Jun Ouyang, Zhifen Guan, Xinhao Zhou, Kai Li, Xueying Sun, Yao Wang.

   Background: Glutamine metabolism presents a promising avenue for cancer prevention and treatment, but the underlying mechanisms in gastric cancer (GC) progression remain elusive.
Methods: The TCGA-STAD and GEO GSE62254 datasets, containing gene expression, clinical information, and survival outcomes of GC, were meticulously examined. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were employed to excavate a key module (MEturquoise), which was used to intersect with glutamine metabolism-related genes (GMRGs) and differentially expressed genes (DEGs) to identify differentially expressed GMRGs (DE-GMRGs). LASSO and Cox Univariate analyses were implemented to determine risk model genes. Correlation of the risk model with clinical parameters, pathways, and tumor immune microenvironments, was analyzed, and its prognostic independence was validated by Cox analyses. Finally, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to validate the expression levels of MYB, LRFN4, LMNB2, and SLC1A5 in GC and para-carcinoma tissue.
Results: The excavation of 4521 DEGs led to the discovery of the key MEturquoise module, which exhibited robust correlations with GC traits. The intersection analysis identified 42 DE-GMRGs, among which six genes showed consistency. Further LASSO analysis established MYB, LRFN4, LMNB2, and SLC1A5 as pivotal risk model genes. The risk model demonstrated associations with oncogenic and metabolism-related pathways, inversely correlating with responses to immune checkpoint blockade therapies. This risk model, together with "age", was validated to be an independent prognostic factor for GC. RT-qPCR result indicated that MYB, LRFN4, LMNB2, and SLC1A5 expressions were remarkably up-regulated in GC tissues comparison with para-carcinoma tissue.
Conclusion: The present study has generated a novel risk module containing four DE-GMRGs for predicting the prognosis and the response to immune checkpoint blockade treatments for GC. This risk model provides new insights into the involvement of glutamine metabolism in GC, warranting further investigation.

Keywords:  Bioinformatic; Gastric cancer; Glutamine metabolism; Risk model

DOI:  https://doi.org/10.1016/j.heliyon.2024.e37985
Environ Sci Technol. 2024 Oct 07.

Benzo(a)anthracene Targeting SLC1A5 to Synergistically Enhance PAH Mixture Toxicity.

Yanwei Wang, Jiahui Zhao, Yipeng Xu, Jing Miao, Keyu Pan, Yihan Li, Yong Chen, Xuesong Liu, Ailin Zhao, Jingyu Qin, Tengfei Xu, Mingliang Fang.

  Human exposure to polycyclic aromatic hydrocarbons (PAHs) as mutagenic and carcinogenic pollutants in the environment often occurs in the form of mixtures. Although the mixture effects of PAHs have been previously recognized, the toxicological mechanisms to explain them still remain quite unclear. This study combined metabolomics and chemical proteomics methods to comprehensively understand the mixture effects of a PAH mixture including benzo(a)anthracene (BaA), benzo(b)fluoranthene (BbF), benzo(a)pyrene (BaP), and chrysene (CHR). Among them, BaA has shown a strong synergistic effect with other PAHs. Interestingly, BaA alone is not a potent oxidative stress inducer in liver cells but dose-dependently amplifies oxidative damage caused by the PAH mixture. Global metabolomics analysis results revealed damage to the antioxidant glutathione synthesis, which was caused by the glutamine depletion caused by BaA in the mixture. Subsequently, the label-free chemical proteomics and cellular thermal shift analysis (CETSA) demonstrated that the PAH mixture altered the thermal shift of glutamine transporter SLC1A5. Furthermore, Western blotting and the isothermal titration calorimetry (ITC) interaction measurements showed nanomolar KD values between BaA and SLC1A5. Overall, this study showed that BaA synergistically contributed to PAH mixture induced oxidative damage by targeting SLC1A5 to inhibit glutamate transport into cells, resulting in the inhibition of glutathione synthesis.

Keywords:  PAHs; SLC1A5; benzo(a)anthracene; chemical proteomics; metabolomics; mixture effects

DOI:  https://doi.org/10.1021/acs.est.4c07053
Metabolomics. 2024 Oct 05. 20(5): 112

Combination of low glucose and SCD1 inhibition impairs cancer metabolic plasticity and growth in MCF-7 cancer cells: a comprehensive metabolomic and lipidomic analysis.

Wentao Zhu, John A Lusk, Vadim Pascua, Danijel Djukovic, Daniel Raftery.

   BACKGROUND: Cancer cells exhibit remarkable metabolic plasticity, enabling them to adapt to fluctuating nutrient conditions. This study investigates the impact of a combination of low glucose levels and inhibition of stearoyl-CoA desaturase 1 (SCD1) using A939572 on cancer metabolic plasticity and growth.
METHODS: A comprehensive metabolomic and lipidomic analysis was conducted to unravel the intricate changes in cellular metabolites and lipids. MCF-7 cells were subjected to low glucose conditions, and SCD1 was inhibited using A939572. The resulting alterations in metabolic pathways and lipid profiles were explored to elucidate the synergistic effects on cancer cell physiology.
RESULTS: The combination of low glucose and A939572-induced SCD1 inhibition significantly impaired cancer cell metabolic plasticity. Metabolomic analysis highlighted shifts in key glycolytic and amino acid pathways, indicating the cells' struggle to adapt to restricted glucose availability. Lipidomic profiling revealed alterations in lipid composition, implying disruptions in membrane integrity and signaling cascades.
CONCLUSION: Our findings underscore the critical roles of glucose availability and SCD1 activity in sustaining cancer metabolic plasticity and growth. Simultaneously targeting these pathways emerges as a promising strategy to impede cancer progression. The comprehensive metabolomic and lipidomic analysis provides a detailed roadmap of molecular alterations induced by this combination treatment, that may help identify potential therapeutic targets.

Keywords:  Cancer metabolism; Glucose deprivation; Lipidomics; Metabolic plasticity; Metabolomics; Stearoyl-CoA desaturase 1

DOI:  https://doi.org/10.1007/s11306-024-02179-y
Fish Shellfish Immunol. 2024 Oct 04. pii: S1050-4648(24)00571-0. [Epub ahead of print]154 109926

Metabolic energetic adaptation of Atlantic salmon phagocytes to changes in carbon sources and exposure to PAMPs.

Daniela Ortiz, Francisco Guajardo, Andrea Talamilla-Espinoza, Francisca Vera-Tamargo, Javiera Pérez-Valenzuela, Madelaine Mejías, Lucas Pino-Quezada, Felipe Galdames-Contreras, Dinka Mandakovic, Jurij Wacyk, Félix A Urra, Rodrigo Pulgar.

  Phagocytic cells are pivotal for host homeostasis and infection defense, necessitating metabolic adaptations in glycolysis, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS). While mammalian phagocytes shift towards glycolysis and glutaminolysis during polarization, research on fish phagocyte metabolic reprogramming is limited. To address this, the Atlantic salmon phagocytic cell line, SHK-1, serves as a valuable model. Using the Seahorse XFe96 Flux Analyzer, this study compares SHK-1 bioenergetics under glucose-restricted (L-15 medium) and glucose-supplemented (PM) conditions, providing insights into metabolic characteristics and responses to Piscirickettsia salmonis bacterium Pathogen-associated molecular patterns (PAMPs). A standardized protocol for the study of real-time changes in the metabolism study of SHK-1 in PM and L-15 media, determining oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) is shown. Exhibiting metabolic adaptations, SHK-1 cells in the PM medium have higher basal and maximal OCR and spare capacity (SRC), while those grown in the L-15 medium favor OXPHOS, showing minimal glycolytic function. Despite metabolic differences, intracellular ATP levels are comparable, highlighting the metabolic plasticity and adaptability of SHK-1 cells to various carbon sources. Exposure to PAMPs from Piscirickettsia salmonis induces a metabolic shift, increasing glycolysis and OXPHOS, influencing ATP, lactate, glutamine, and glutamate levels. These findings highlight the role of mitochondrial bioenergetics and metabolic plasticity in salmon phagocytes, offering novel nutritional strategies for host-pathogen interventions based on energy metabolism.

Keywords:  Atlantic salmon phagocytes; Immunometabolism; Metabolic plasticity; Mitochondrial bioenergetics; Seahorse XF analyzer

DOI:  https://doi.org/10.1016/j.fsi.2024.109926
Curr Opin Immunol. 2024 Oct 04. pii: S0952-7915(24)00081-5. [Epub ahead of print]91 102491

Metabolism and macrophages in the tumor microenvironment.

Hannah Yang, Chan Kim, Weiping Zou.

Tumor-associated macrophages (TAMs) constitute the primary subset of immune cells within the tumor microenvironment (TME). Exhibiting both phenotypic and functional heterogeneity, TAMs play distinct roles in tumor initiation, progression, and responses to therapy in patients with cancer. In response to various immune and metabolic cues within the TME, TAMs dynamically alter their metabolic profiles to adapt. Changes in glucose, amino acid, and lipid metabolism in TAMs, as well as their interaction with oncometabolites, not only sustain their energy demands but also influence their impact on tumor immune responses. Understanding the molecular mechanisms underlying the metabolic reprogramming of TAMs and their orchestration of metabolic processes can offer insights for the development of novel cancer immunotherapies targeting TAMs. Here, we discuss how metabolism reprograms macrophages in the TME and review clinical trials aiming to normalize metabolic alterations in TAMs and alleviate TAM-mediated immune suppression and protumor activity.

DOI: https://doi.org/10.1016/j.coi.2024.102491
Cancer Manag Res. 2024 ;16 1329-1344

Impact of Glutamine-Enhanced Parenteral Nutrition on Postoperative Outcomes in Colorectal Cancer Patients.

Yong Huang, Chunmei Yin, Jue Wang, Maijian Wang, Xingbin Zheng, Ming Xie, Jiwei Wang.

   Purpose: This study investigated the effects of parenteral glutamine (Gln) supplement immunonutrition versus conventional nutritional support on postoperative Clavien-Dindo classification complications and recovery, perioperative nutritional status, and immune, inflammation, and safety indicators in patients with colorectal cancer (CRC).
Patients and Methods: Clinical data were collected for a retrospective cohort study of 178 patients (58 and 120 patients in the observation and control groups, respectively) who underwent radical resection of CRC from January 2019 to December 2021. The incidence of postoperative complications was calculated. Postoperative recovery, nutritional indicators, inflammatory factors indicator, and the safety indicators before operation and at 1, 3, and 7 days after operation were compared. SPSS 29.0 statistical software was used for statistical analysis.
Results: The incidence of postoperative overall complications in the control group and the observation group was 22.50% (27/120) and 17.24% (10/58), respectively, and there was no significant difference between the two groups (P=0.42). The incidence of postoperative complications of Clavien-Dindo grade ≥III in the control group and the observation group was 14.17% (17/120) and 3.45% (2/58), respectively, and the difference between the two groups was statistically significant (P=0.03). Secondary outcomes (first exhaust, defecation, and liquid diet intake times) were significantly recovered earlier in the observation group than those in the control group (P<0.05), while the postoperative hospital stay was significantly shorter(P=0.04). The perioperative nutritional status did not significantly differ between the groups before and after surgery(P>0.05), although significant differences were observed in several inflammatory and safety indicators(P<0.05).
Conclusion: Unlike conventional nutritional support, postoperative parenteral Gln supplementation reduced the incidence of postoperative Clavien-Dindo complications grade ≥III in patients with CRC while increasing intestinal and immune functions, decreasing inflammation, and reducing the length of hospital stay.

Keywords:  clavien–dindo complication; colorectal cancer; glutamine; parenteral nutrition

DOI:  https://doi.org/10.2147/CMAR.S476648
J Chromatogr B Analyt Technol Biomed Life Sci. 2024 Oct 04. pii: S1570-0232(24)00345-3. [Epub ahead of print]1247 124336

Serum metabolome alterations in hyperhomocysteinemia based on targeted and non-targeted MS-platforms.

Xinshu Zhao, Xiaowei Liu, Liyan Liu, Rui Chen.

   BACKGROUND AND AIMS: Hyperhomocysteinemia (Hhcy) is a pathological condition marked by increased level of homocysteine and serves as an independent risk factor for a range of diseases including cardiovascular diseases and Alzheimer's disease. This study aims to examine alterations in Hhcy-related metabolites using serum metabolomics and unravel the distinct metabolic pathways involved, thereby offering a theoretical foundation for the early prevention and treatment of Hhcy.
METHODS: Serum samples were collected from 56 individuals with Hhcy and 44 healthy controls. Metabolic alterations in Hhcy were assessed through multi-platform serum metabolomics analyses. Through multivariate statistical analysis and regression modeling, distinct metabolites in the serum were identified, and various metabolic pathways associated with Hhcy were investigated.
RESULTS: Our findings revealed 21 significant different metabolites that distinguished Hhcy from healthy controls. These varied metabolites primarily comprised 10 organic acids, 4 amino acids, 2 fatty acids, and 5 other metabolites. The key differential metabolic pathways identified were the TCA cycle, pyruvate metabolism, arginine biosynthesis, as well as alanine, aspartate, and glutamate metabolism.
CONCLUSIONS: This study elucidated the variances in metabolic profiles between Hhcy and healthy control groups, highlighting distinct metabolic pathways that may help explain the etiology of Hhcy. These findings offer valuable insights to address the knowledge gaps related to the metabolic alterations associated with Hhcy.

Keywords:  Different metabolites; Hyperhomocysteinemia; Metabolomics; Pathway analysis

DOI:  https://doi.org/10.1016/j.jchromb.2024.124336
Microb Cell Fact. 2024 Oct 07. 23(1): 267

Exploiting phenotypic heterogeneity to improve production of glutathione by yeast.

Mingzhi Xu, Cindy Vallières, Chris Finnis, Klaus Winzer, Simon V Avery.

   BACKGROUND: Gene expression noise (variation in gene expression among individual cells of a genetically uniform cell population) can result in heterogenous metabolite production by industrial microorganisms, with cultures containing both low- and high-producing cells. The presence of low-producing individuals may be a factor limiting the potential for high yields. This study tested the hypothesis that low-producing variants in yeast cell populations can be continuously counter-selected, to increase net production of glutathione (GSH) as an exemplar product.
RESULTS: A counter-selection system was engineered in Saccharomyces cerevisiae based on the known feedback inhibition of gamma-glutamylcysteine synthetase (GSH1) gene expression, which is rate limiting for GSH synthesis: the GSH1 ORF and the counter-selectable marker GAP1 were expressed under control of the TEF1 and GSH-regulated GSH1 promoters, respectively. An 18% increase in the mean cellular GSH level was achieved in cultures of the engineered strain supplemented with D-histidine to counter-select cells with high GAP1 expression (i.e. low GSH-producing cells). The phenotype was non-heritable and did not arise from a generic response to D-histidine, unlike that with certain other test-constructs prepared with alternative markers.
CONCLUSIONS: The results corroborate that the system developed here improves GSH production by targeting low-producing cells. This supports the potential for exploiting end-product/promoter interactions to enrich high-producing cells in phenotypically heterogeneous populations, in order to improve metabolite production by yeast.

Keywords:  Bioprocess optimization; Cell individuality; Metabolic engineering; Phenotypic heterogeneity; Yeast metabolism

DOI:  https://doi.org/10.1186/s12934-024-02536-5
Int Immunopharmacol. 2024 Oct 04. pii: S1567-5769(24)01838-1. [Epub ahead of print]143(Pt 1): 113316

Dietary glutamine supplementation improves both Th1 and Th17 responses via CARD11-mTORC1 pathway in murine model of atopic dermatitis.

Junwen Fan, Xiaoming Wang, Yufei Wang, Jingjing Song, Mingxin Chen, Cuiye Weng, Lei Wang, Zailong Chi, Weixi Zhang.

  Glutamine (GLN) is considered an immunomodulatory nutrient, while caspase recruitment domain 11 (CARD11) is a susceptibility locus for atopic dermatitis (AD). T-cell antigen receptor (TCR)-stimulated GLN uptake requires CARD11. However, the specific pathogenesis of AD via GLN uptake remains unclear. This study aimed to elucidate the association between dietary GLN supplementation and the CARD11 pathway in the pathogenesis of AD, focusing on T helper type 1 (Th1) and Th17 cell expression in AD. Herein, wild-type (WT) mice with house dust mite epidermal-sensitized skin exhibited increased expression of interferon-gamma (IFN-gamma) and interleukin (IL)-17, whereas CARD11 deficiency impaired Th1 and Th17 responses at the same site. CARD11 is a key mediator of Th1 and Th17 expression in AD. Additionally, we suppressed mammalian target of rapamycin complex 1 (mTORC1) signaling, downstream of CARD11, to underscore the critical role of CARD11 in mediating Th1 and Th17 expression in AD. Further, dietary supplementation of GLN to CARD11-/- mice restored Th1 and Th17 responses, whereas inflammatory expression was reduced in WT mice, and p-CARD11 expression and mTORC1 signaling activity were increased in JPM50.6 cells and CARD11-/- mice. Upon inhibiting the GLN transporter, alanine-serine-cysteine transporter carrier 2 (ASCT2), we observed that the Th1 and Th17 response in AD was reduced. Conclusively, ASCT2-mediated GLN uptake improves the expression of Th1 and Th17 cells via CARD11-mTORC1 signaling pathway in AD, suggesting the potential of glutamine supplementation for AD treatment.

Keywords:  ASCT2; Atopic dermatitis; CARD11; Glutamine; Th1; Th17; mTORC1

DOI:  https://doi.org/10.1016/j.intimp.2024.113316
EBioMedicine. 2024 Oct 10. pii: S2352-3964(24)00425-0. [Epub ahead of print]109 105389

Single cell atlas reveals multilayered metabolic heterogeneity across tumour types.

Zhe Zhou, Di Dong, Yuyao Yuan, Juan Luo, Xiao-Ding Liu, Long-Yun Chen, Guangxi Wang, Yuxin Yin.

   BACKGROUND: Metabolic reprogramming plays a pivotal role in cancer progression, contributing to substantial intratumour heterogeneity and influencing tumour behaviour. However, a systematic characterization of metabolic heterogeneity across multiple cancer types at the single-cell level remains limited.
METHODS: We integrated 296 tumour and normal samples spanning six common cancer types to construct a single-cell compendium of metabolic gene expression profiles and identify cell type-specific metabolic properties and reprogramming patterns. A computational approach based on non-negative matrix factorization (NMF) was utilised to identify metabolic meta-programs (MMPs) showing intratumour heterogeneity. In-vitro cell experiments were conducted to confirm the associations between MMPs and chemotherapy resistance, as well as the function of key metabolic regulators. Survival analyses were performed to assess clinical relevance of cellular metabolic properties.
FINDINGS: Our analysis revealed shared glycolysis upregulation and divergent regulation of citric acid cycle across different cell types. In malignant cells, we identified a colorectal cancer-specific MMP associated with resistance to the cuproptosis inducer elesclomol, validated through in-vitro cell experiments. Furthermore, our findings enabled the stratification of patients into distinct prognostic subtypes based on metabolic properties of specific cell types, such as myeloid cells.
INTERPRETATION: This study presents a nuanced understanding of multilayered metabolic heterogeneity, offering valuable insights into potential personalized therapies targeting tumour metabolism.
FUNDING: National Key Research and Development Program of China (2021YFA1300601). National Natural Science Foundation of China (key grants 82030081 and 81874235). The Shenzhen High-level Hospital Construction Fund and Shenzhen Basic Research Key Project (JCYJ20220818102811024). The Lam Chung Nin Foundation for Systems Biomedicine.

Keywords:  Cancer metabolism; Chemotherapy resistance; Metabolic heterogeneity; Pan-cancer analysis; scRNA-seq

DOI:  https://doi.org/10.1016/j.ebiom.2024.105389
Biomaterials. 2024 Oct 05. pii: S0142-9612(24)00411-3. [Epub ahead of print]314 122877

Glutamine synthetase accelerates re-endothelialization of vascular grafts by mitigating endothelial cell dysfunction in a rat model.

Xinbo Wei, Li Wang, Zheng Xing, Peng Chen, Xi He, Xiaoye Tuo, Haoran Su, Gang Zhou, Haifeng Liu, Yubo Fan.

  Endothelial cell (EC) dysfunction within the aorta has long been recognized as a prominent contributor to the progression of atherosclerosis and the subsequent failure of vascular graft transplantation. However, the direct relationship between EC dysfunction and vascular remodeling remains to be investigated. In this study, we sought to address this knowledge gap by employing a strategy involving the release of glutamine synthetase (GS), which effectively activated endothelial metabolism and mitigates EC dysfunction. To achieve this, we developed GS-loaded small-diameter vascular grafts (GSVG) through the electrospinning technique, utilizing dual-component solutions consisting of photo-crosslinkable hyaluronic acid and polycaprolactone. Through an in vitro model of oxidized low-density lipoprotein-induced injury in human umbilical vein endothelial cells (HUVECs), we provided compelling evidence that the GSVG promoted the restoration of motility, angiogenic sprouting, and proliferation in dysfunctional HUVECs by enhancing cellular metabolism. Furthermore, the sequencing results indicated that these effects were mediated by miR-122-5p-related signaling pathways. Remarkably, the GSVG also exhibited regulatory capabilities in shifting vascular smooth muscle cells towards a contractile phenotype, mitigating inflammatory responses and thereby preventing vascular calcification. Finally, our data demonstrated that GS incorporation significantly enhanced re-endothelialization of vascular grafts in a ferric chloride-injured rat model. Collectively, our results offer insights into the promotion of re-endothelialization in vascular grafts by restoring dysfunctional ECs through the augmentation of cellular metabolism.

Keywords:  Atherosclerosis; Cellular metabolism; Endothelial cell dysfunction; Glutamine synthetase; Small-vascular graft

DOI:  https://doi.org/10.1016/j.biomaterials.2024.122877
Nat Commun. 2024 Oct 06. 15(1): 8658

GLUT1 overexpression in CAR-T cells induces metabolic reprogramming and enhances potency.

Justin A Guerrero, Dorota D Klysz, Yiyun Chen, Meena Malipatlolla, Jameel Lone, Carley Fowler, Lucille Stuani, Audre May, Malek Bashti, Peng Xu, Jing Huang, Basil Michael, Kévin Contrepois, Shaurya Dhingra, Chris Fisher, Katrin J Svensson, Kara L Davis, Maya Kasowski, Steven A Feldman, Elena Sotillo, Crystal L Mackall.

The intensive nutrient requirements needed to sustain T cell activation and proliferation, combined with competition for nutrients within the tumor microenvironment, raise the prospect that glucose availability may limit CAR-T cell function. Here, we seek to test the hypothesis that stable overexpression (OE) of the glucose transporter GLUT1 in primary human CAR-T cells would improve their function and antitumor potency. We observe that GLUT1OE in CAR-T cells increases glucose consumption, glycolysis, glycolytic reserve, and oxidative phosphorylation, and these effects are associated with decreased T cell exhaustion and increased Th17 differentiation. GLUT1OE also induces broad metabolic reprogramming associated with increased glutathione-mediated resistance to reactive oxygen species, and increased inosine accumulation. When challenged with tumors, GLUT1OE CAR-T cells secrete more proinflammatory cytokines and show enhanced cytotoxicity in vitro, and demonstrate superior tumor control and persistence in mouse models. Our collective findings support a paradigm wherein glucose availability is rate limiting for effector CAR-T cell function and demonstrate that enhancing glucose availability via GLUT1OE could augment antitumor immune function.

DOI: https://doi.org/10.1038/s41467-024-52666-y