bims-glucam 2024-09-08 papers

bims-glucam

Biomed News

on Glutamine cancer metabolism

Issue of 2024–09–08
23 papers selected by
Sreeparna Banerjee, Middle East Technical University

A Ketogenic Diet Sensitizes Pancreatic Cancer to Inhibition of Glutamine Metabolism.
Glutamine and leukemia research: progress and clinical prospects.
Combinatorial targeting of glutamine metabolism and lysosomal-based lipid metabolism effectively suppresses glioblastoma.
Glutaminase 1 plays critical roles in myelodysplastic syndrome and acute myeloid leukemia cells.
p53 Orchestrates Cancer Metabolism: Unveiling Strategies to Reverse the Warburg Effect.
Targeting amino acid-metabolizing enzymes for cancer immunotherapy.
The disruption of NEAT1-miR-125b-5p-SLC1A5 cascade defines the oncogenicity and differential immune profile in head and neck squamous cell carcinoma.
Mechanisms governing lineage plasticity and metabolic reprogramming in cancer.
Proteo-metabolomics and patient tumor slice experiments point to amino acid centrality for rewired mitochondria in fibrolamellar carcinoma.
GABAA receptor modulation by the endocannabinoid system: insights into the regulatory mechanisms involving glutamine synthetase and MAPK mediators.
Glutathione inhibits lung cancer development by reducing interleukin-6 expression and reversing the Warburg effect.
Multi-omics profiling combined with molecular docking reveals immune-inflammatory proteins as potential drug targets in colorectal cancer.
Polarization of Macrophages in Tumor Microenvironment Using High-Throughput Single-Cell Metabolomics.
Metabolic Phenotyping of Healthy and Diseased Human RPE Cells.
Perturbations in mitochondrial metabolism associated with defective cardiolipin biosynthesis: An in-organello real-time NMR study.
Metabolomics Reveals Disturbed Amino Acid Metabolism During Different Stages of RA in Collagen-Induced Arthritis Mice.
Acidity induces durable enhancement of Treg cell suppressive functions for tumor immune evasion.
Mitochondrial damage precedes the changes of glutathione metabolism in CdCl2 treated neuronal SH-SY5Y cells.
HADH suppresses clear cell renal cell carcinoma progression through reduced NRF2-dependent glutathione synthesis.
The Role of S-Glutathionylation in Health and Disease: A Bird's Eye View.
The solute carrier transporters (SLCs) family in nutrient metabolism and ferroptosis.
Metabolic reprogramming and immune evasion: the interplay in the tumor microenvironment.
A glutathione responsive photosensitizer based on hypocrellin B for photodynamic therapy.

bioRxiv. 2024 Jul 23. pii: 2024.07.19.604377. [Epub ahead of print]

A Ketogenic Diet Sensitizes Pancreatic Cancer to Inhibition of Glutamine Metabolism.

Omid Hajihassani, Mehrdad Zarei, Asael Roichman, Alexander Loftus, Christina S Boutros, Jonathan Hue, Parnian Naji, Jacob Boyer, Soubhi Tahan, Peter Gallagher, William Beegan, James Choi, Shihong Lei, Christine Kim, Moeez Rathore, Faith Nakazzi, Ishan Shah, Kevin Lebo, Helen Cheng, Anusha Mudigonda, Sydney Alibeckoff, Karen Ji, Hallie Graor, Masaru Miyagi, Ali Vaziri-Gohar, Henri Brunengraber, Rui Wang, Peder J Lund, Luke D Rothermel, Joshua D Rabinowitz, Jordan M Winter.

Pancreatic cancer is the third leading cause of cancer death in the United States, and while conventional chemotherapy remains the standard treatment, responses are poor. Safe and alternative therapeutic strategies are urgently needed 1 . A ketogenic diet has been shown to have anti-tumor effects across diverse cancer types but will unlikely have a significant effect alone. However, the diet shifts metabolism in tumors to create new vulnerabilities that can be targeted (1). Modulators of glutamine metabolism have shown promise in pre-clinical models but have failed to have a marked impact against cancer in the clinic. We show that a ketogenic diet increases TCA and glutamine-associated metabolites in murine pancreatic cancer models and under metabolic conditions that simulate a ketogenic diet in vitro. The metabolic shift leads to increased reliance on glutamine-mediated anaplerosis to compensate for low glucose abundance associated with a ketogenic diet. As a result, glutamine metabolism inhibitors, such as DON and CB839 in combination with a ketogenic diet had robust anti-cancer effects. These findings provide rationale to study the use of a ketogenic diet with glutamine targeted therapies in a clinical context.

DOI: https://doi.org/10.1101/2024.07.19.604377
Discov Oncol. 2024 Aug 31. 15(1): 391

Glutamine and leukemia research: progress and clinical prospects.

Zexin Wang, Miao Liu, Qiang Yang.

  Leukemia is an abnormal proliferation of white blood cells that occurs in bone marrow and expands through the blood. It arises from dysregulated differentiation, uncontrolled growth, and inhibition of apoptosis. Glutamine (GLN) is a "conditionally essential" amino acid that promotes growth and proliferation of leukemic cells. Recently, details about the role of GLN and its metabolism in the diagnosis and treatment of acute myeloid, chronic lymphocytic, and acute lymphoblastic leukemia have emerged. The uptake of GLN by leukemia cells and the dynamic changes of glutamine-related indexes in leukemia patients may be able to assist in determining whether the condition of leukemia is in a state of progression, remission or relapse. Utilizing the possible differences in GLN metabolism in different subtypes of leukemia may help to differentiate between different subtypes of leukemia, thus providing a basis for accurate diagnosis. Targeting GLN metabolism in leukemia requires simultaneous blockade of multiple metabolic pathways without interfering with the normal cellular and immune functions of the body to achieve effective leukemia therapy. The present review summarizes recent advances, possible applications, and clinical perspectives of GLN metabolism in leukemia. In particular, it focuses on the prospects of GLN metabolism in the diagnosis and treatment of acute myeloid leukemia. The review provides new directions and hints at potential roles for future clinical treatments and studies.

Keywords:  Glutaminase; Glutamine; Glutamine metabolism; Glutamine transporter protein; Leukemia

DOI:  https://doi.org/10.1007/s12672-024-01245-0
Cell Rep Med. 2024 Aug 28. pii: S2666-3791(24)00427-0. [Epub ahead of print] 101706

Combinatorial targeting of glutamine metabolism and lysosomal-based lipid metabolism effectively suppresses glioblastoma.

Yaogang Zhong, Feng Geng, Logan Mazik, Xinmin Yin, Aline Paixao Becker, Shabber Mohammed, Huali Su, Enming Xing, Yongjun Kou, Cheng-Yao Chiang, Yunzhou Fan, Yongchen Guo, Qiang Wang, Pui-Kai Li, Xiaokui Mo, Etienne Lefai, Liqing He, Xiaolin Cheng, Xiang Zhang, Arnab Chakravarti, Deliang Guo.

  Antipsychotic drugs have been shown to have antitumor effects but have had limited potency in the clinic. Here, we unveil that pimozide inhibits lysosome hydrolytic function to suppress fatty acid and cholesterol release in glioblastoma (GBM), the most lethal brain tumor. Unexpectedly, GBM develops resistance to pimozide by boosting glutamine consumption and lipogenesis. These elevations are driven by SREBP-1, which we find upregulates the expression of ASCT2, a key glutamine transporter. Glutamine, in turn, intensifies SREBP-1 activation through the release of ammonia, creating a feedforward loop that amplifies both glutamine metabolism and lipid synthesis, leading to drug resistance. Disrupting this loop via pharmacological targeting of ASCT2 or glutaminase, in combination with pimozide, induces remarkable mitochondrial damage and oxidative stress, leading to GBM cell death in vitro and in vivo. Our findings underscore the promising therapeutic potential of effectively targeting GBM by combining glutamine metabolism inhibition with lysosome suppression.

Keywords:  ASCT2; GLS; SREBP-1; cholesterol; fatty acids; glioblastoma; glutamine; lipid droplets; lysosome; pimozide

DOI:  https://doi.org/10.1016/j.xcrm.2024.101706
Cancer Biomark. 2024 Aug 02.

Glutaminase 1 plays critical roles in myelodysplastic syndrome and acute myeloid leukemia cells.

Seiichi Okabe, Mitsuru Moriyama, Yuya Arai, Akihiko Gotoh.

   BACKGROUND: Myelodysplastic syndrome (MDS) features bone marrow failure and a heightened risk of evolving into acute myeloid leukemia (AML), increasing with age and reducing overall survival. Given the unfavorable outcomes of MDS, alternative treatments are necessary. Glutamine, the most abundant amino acid in the blood, is metabolized first by the enzyme glutaminase (GLS).
OBJECTIVES: To investigate whether GLS is involved in the progression of MDS. The efficacy of GLS inhibitors (CB839 or IPN60090) and BCL2 inhibitor venetoclax was also examined.
METHODS: We employed GLS inhibitors (CB839, IPN60090) and the BCL2 inhibitor venetoclax, prepared as detailed. MDS and AML cell lines were cultured under standard and modified (hypoxic, glutamine-free) conditions. Viability, proliferation, and caspase activity were assessed with commercial kits. RT-PCR quantified gene expression post-shRNA transfection. Mitochondrial potential, ATP levels, proteasome activity, and metabolic functions were evaluated using specific assays. Statistical analyses (t-tests, ANOVA) validated the findings.
RESULTS: The glutamine-free medium inhibited the growth of MDS cells. GLS1 expression was higher in AML cells than in normal control samples (GSE15061), whereas GLS2 expression was not. Treatment of MDS and AML cells for 72 h was inhibited in a dose-dependent manner by GLS inhibitors. Co-treatment with the B-cell lymphoma 2 (BCL2) inhibitor venetoclax and GLS inhibitors increased potency. Cells transfected with GLS1 short hairpin RNA showed suppressed proliferation under hypoxic conditions and increased sensitivity to venetoclax.
CONCLUSIONS: Targeting glutaminolysis and BCL2 inhibition enhances the therapeutic efficacy and has been proposed as a novel strategy for treating high-risk MDS and AML.

Keywords:  AML; BCL-2 inhibitor; GLS inhibitor; Glutaminolysis; MDS; hypoxia

DOI:  https://doi.org/10.3233/CBM-230454
Bull Math Biol. 2024 Aug 29. 86(10): 124

p53 Orchestrates Cancer Metabolism: Unveiling Strategies to Reverse the Warburg Effect.

Roba Abukwaik, Elias Vera-Siguenza, Daniel Tennant, Fabian Spill.

  Cancer cells exhibit significant alterations in their metabolism, characterised by a reduction in oxidative phosphorylation (OXPHOS) and an increased reliance on glycolysis, even in the presence of oxygen. This metabolic shift, known as the Warburg effect, is pivotal in fuelling cancer's uncontrolled growth, invasion, and therapeutic resistance. While dysregulation of many genes contributes to this metabolic shift, the tumour suppressor gene p53 emerges as a master player. Yet, the molecular mechanisms remain elusive. This study introduces a comprehensive mathematical model, integrating essential p53 targets, offering insights into how p53 orchestrates its targets to redirect cancer metabolism towards an OXPHOS-dominant state. Simulation outcomes align closely with experimental data comparing glucose metabolism in colon cancer cells with wild-type and mutated p53. Additionally, our findings reveal the dynamic capability of elevated p53 activation to fully reverse the Warburg effect, highlighting the significance of its activity levels not just in triggering apoptosis (programmed cell death) post-chemotherapy but also in modifying the metabolic pathways implicated in treatment resistance. In scenarios of p53 mutations, our analysis suggests targeting glycolysis-instigating signalling pathways as an alternative strategy, whereas targeting solely synthesis of cytochrome c oxidase 2 (SCO2) does support mitochondrial respiration but may not effectively suppress the glycolysis pathway, potentially boosting the energy production and cancer cell viability.

Keywords:  Cancer metabolism; Glycolysis; Hypoxia; Mathematical biology; Warburg effect; p53

DOI:  https://doi.org/10.1007/s11538-024-01346-5
Front Immunol. 2024 ;15 1440269

Targeting amino acid-metabolizing enzymes for cancer immunotherapy.

Yvonne Grobben.

  Despite the immune system's role in the detection and eradication of abnormal cells, cancer cells often evade elimination by exploitation of various immune escape mechanisms. Among these mechanisms is the ability of cancer cells to upregulate amino acid-metabolizing enzymes, or to induce these enzymes in tumor-infiltrating immunosuppressive cells. Amino acids are fundamental cellular nutrients required for a variety of physiological processes, and their inadequacy can severely impact immune cell function. Amino acid-derived metabolites can additionally dampen the anti-tumor immune response by means of their immunosuppressive activities, whilst some can also promote tumor growth directly. Based on their evident role in tumor immune escape, the amino acid-metabolizing enzymes glutaminase 1 (GLS1), arginase 1 (ARG1), inducible nitric oxide synthase (iNOS), indoleamine 2,3-dioxygenase 1 (IDO1), tryptophan 2,3-dioxygenase (TDO) and interleukin 4 induced 1 (IL4I1) each serve as a promising target for immunotherapeutic intervention. This review summarizes and discusses the involvement of these enzymes in cancer, their effect on the anti-tumor immune response and the recent progress made in the preclinical and clinical evaluation of inhibitors targeting these enzymes.

Keywords:  IDO1; IL4I1; amino acid metabolism; arginine; cancer immunotherapy; glutamine; immunosuppression; tryptophan

DOI:  https://doi.org/10.3389/fimmu.2024.1440269
Cell Death Discov. 2024 Sep 03. 10(1): 392

The disruption of NEAT1-miR-125b-5p-SLC1A5 cascade defines the oncogenicity and differential immune profile in head and neck squamous cell carcinoma.

Ying-Chieh Liu, So-Yu Liu, Yu-Cheng Lin, Chung-Ji Liu, Kuo-Wei Chang, Shu-Chun Lin.

Metabolic reprogramming sustains malignant head and neck squamous cell carcinoma (HNSCC) to overcome stressful microenvironments, and increased glutamine uptake is a common metabolic hallmark in cancers. Since metabolic reprogramming has been recognized as a new therapeutic target for tumor cells, understanding the regulatory axis of glutamine uptake in HNSCC and its potential downstream effects in its pathogenesis of HNSCC would be incredibly beneficial. Bioinformatic analysis of the Cancer Genome Atlas (TCGA)-HNSCC dataset and RNAseq analysis performed on HNSCC indicated that SLC1A5 was the most dysregulated transporter among the seven homologous glutamate or neutral amino acid transporters in the SLC1A family. To further clarify the role of SLC1A5 in HNSCC, we knocked down SLC1A5 expression. This knockdown decelerated cell growth, induced G0/G1 arrest, diminished tumorigenicity, and increased cleavage caspase3, LC3B, and intracellular Fe2+. Inhibitors against apoptosis, autophagy, or ferroptosis rescued the cell viability repressed by SLC1A5 knockdown. SLC1A5 knockdown also suppressed glutamine uptake, enhanced oxidative stress, and increased sensitivity to cisplatin. CRISPR/dCas9-mediated SLC1A5 induction conferred cisplatin resistance and reduced apoptosis, autophagy, and ferroptosis. Reporter assays and western blot data demonstrated that miR-125b-5p targets and attenuates SLC1A5, while the si-NEAT1 increases miR-125b-5p expression. Analysis of the TCGA-HNSCC databases showed concordant upregulation of NEAT1 and downregulation of miR-125b-5p, along with SLC1A5 upregulation in tumors. Analysis of transcriptomic data revealed that tumors harboring higher SLC1A5 expression had significantly lower immune scores in CD8+, monocytes, and dendritic cells, and higher scores in M0 and M1 macrophages. Disruptions in immune modulation, metabolism, and oxidative stress components were associated with SLC1A5 aberrations in HNSCC. This study concludes that the NEAT1/miR-125b-5p/SLC1A5 cascade modulates diverse activities in oncogenicity, treatment efficacy, and immune cell profiles in head and neck/oral carcinoma.

DOI: https://doi.org/10.1038/s41420-024-02158-1
Trends Cancer. 2024 Aug 31. pii: S2405-8033(24)00168-7. [Epub ahead of print]

Mechanisms governing lineage plasticity and metabolic reprogramming in cancer.

Lillian M Perez, Smrruthi V Venugopal, Anna St Martin, Stephen J Freedland, Dolores Di Vizio, Michael R Freeman.

  Dynamic alterations in cellular phenotypes during cancer progression are attributed to a phenomenon known as 'lineage plasticity'. This process is associated with therapeutic resistance and involves concurrent shifts in metabolic states that facilitate adaptation to various stressors inherent in malignant growth. Certain metabolites also serve as synthetic reservoirs for chromatin modification, thus linking metabolic states with epigenetic regulation. There remains a critical need to understand the mechanisms that converge on lineage plasticity and metabolic reprogramming to prevent the emergence of lethal disease. This review attempts to offer an overview of our current understanding of the interplay between metabolic reprogramming and lineage plasticity in the context of cancer, highlighting the intersecting drivers of cancer hallmarks, with an emphasis on solid tumors.

Keywords:  cancer metabolism; epigenetics; lineage plasticity; metabolic reprogramming

DOI:  https://doi.org/10.1016/j.trecan.2024.08.001
Cell Rep Med. 2024 Aug 21. pii: S2666-3791(24)00420-8. [Epub ahead of print] 101699

Proteo-metabolomics and patient tumor slice experiments point to amino acid centrality for rewired mitochondria in fibrolamellar carcinoma.

Donald Long, Marina Chan, Mingqi Han, Zeal Kamdar, Rosanna K Ma, Pei-Yin Tsai, Adam B Francisco, Joeva Barrow, David B Shackelford, Mark Yarchoan, Matthew J McBride, Lukas M Orre, Nathaniel M Vacanti, Taranjit S Gujral, Praveen Sethupathy.

  Fibrolamellar carcinoma (FLC) is a rare, lethal, early-onset liver cancer with a critical need for new therapeutics. The primary driver in FLC is the fusion oncoprotein, DNAJ-PKAc, which remains challenging to target therapeutically. It is critical, therefore, to expand understanding of the FLC molecular landscape to identify druggable pathways/targets. Here, we perform the most comprehensive integrative proteo-metabolomic analysis of FLC. We also conduct nutrient manipulation, respirometry analyses, as well as key loss-of-function assays in FLC tumor tissue slices from patients. We propose a model of cellular energetics in FLC pointing to proline anabolism being mediated by ornithine aminotransferase hyperactivity and ornithine transcarbamylase hypoactivity with serine and glutamine catabolism fueling the process. We highlight FLC's potential dependency on voltage-dependent anion channel (VDAC), a mitochondrial gatekeeper for anions including pyruvate. The metabolic rewiring in FLC that we propose in our model, with an emphasis on mitochondria, can be exploited for therapeutic vulnerabilities.

Keywords:  alpha-ketoglutarate; fibrolamellar carcinoma; glucose; glutamine; metabolomics; mitochondria; proline; proteomics; pyruvate; serine

DOI:  https://doi.org/10.1016/j.xcrm.2024.101699
Hum Cell. 2024 Aug 29.

GABAA receptor modulation by the endocannabinoid system: insights into the regulatory mechanisms involving glutamine synthetase and MAPK mediators.

Sina Pakkhesal.

DOI: https://doi.org/10.1007/s13577-024-01126-2
Mitochondrion. 2024 Aug 28. pii: S1567-7249(24)00111-9. [Epub ahead of print] 101953

Glutathione inhibits lung cancer development by reducing interleukin-6 expression and reversing the Warburg effect.

Chenchen Fan, Guojie Chen, Russel J Reiter, Yidong Bai, Tiansheng Zheng, Lihong Fan.

  Reduced glutathione (GSH) is widely used as an antioxidant in clinical practice, but whether GSH affects the development of early lung cancer remains unclear. Herein, we investigated the mechanism underlying the anticancer effect of GSH in patients with pulmonary nodules. Thirty patients with pulmonary nodules were treated with GSH intravenously for 10 days at a dose of 1.8 g/d, followed by oral administration of the drug at a dose of 0.4 g three times daily for 6 months. The results showed that GSH treatment promoted nodule absorption and reduced the IL-6 level in the peripheral blood of the patients. GSH reduced IL-6 expression in inflammatory BEAS-2B and lung cancer cells and inhibited the proliferation of lung cancer cell lines in vitro. In addition, GSH reduced IL-6 expression by decreasing ROS via down-regulating PI3K/AKT/FoxO pathways. Finally, GSH reversed the Warburg effect, restored mitochondrial function, and reduced the IL-6 expression via PI3K/AKT/FoxO pathways. The in vivo experiment confirmed that GSH inhibited lung cancer growth, improved mitochondrial function, and reduced the IL-6 expression by regulating key enzymes via the PI3K/AKT/FoxO pathway. In conclusion, we uncovered that GSH exerts an unprecedentedly potent anti-cancer effect to prevent the transformation of lung nodules to lung cancer by improving the mitochondrial function and suppressing inflammation via PI3K/AKT/FoxO pathway. This investigation innovatively positions GSH as a potentially safe and efficacious old drug with new uses, inhibiting inflammation and early lung cancer. The use of the drug offers a promising preventive strategy when administered during the early stages of lung cancer.

Keywords:  Energy metabolism; IL-6; Inflammatory cells; Lung cancer; Mitochondria; Reduced glutathione

DOI:  https://doi.org/10.1016/j.mito.2024.101953
Biochem Biophys Res Commun. 2024 Aug 23. pii: S0006-291X(24)01134-3. [Epub ahead of print]739 150598

Multi-omics profiling combined with molecular docking reveals immune-inflammatory proteins as potential drug targets in colorectal cancer.

Xiaoping Dong, Kun Zhang, Siwei Yi, Lingxiang Wang, Xingyao Wang, Mengtuo Li, Songping Liang, YongJun Wang, Yong Zeng.

  Colorectal cancer is globally ranked as the third most common malignant tumor. Its development involves a complex biological process driven by various genetic and epigenetic alterations. To elucidate the biological significance of the extensive omics data, we conducted comparative multi-omics studies on colorectal cancer patients at different clinical stages. Bioinformatics methods were applied to analyze multi-omics datasets and explore the molecular landscape. Drug prediction and molecular docking also were conducted to assess potential therapeutic interventions. In vitro experiments were used to validate the inhibitory effect on the migration and proliferation of cell lines. The results indicate up-regulated proteins involved in immune-inflammatory related pathways, while biomarkers related to muscular contraction and cell adhesion are significantly down-regulated. Drug prediction, coupled with in vitro experiments, suggests that AZ-628 may act as a potential drug to inhibit the proliferation and migration of CRC cell lines HCT-116 and HT-29 by regulating the aforementioned key biological pathways or proteins. Complementing these findings, metabolomics analysis unveiled a down-regulation of key carbon metabolism pathways, alongside an up-regulation in amino acid metabolism, particularly proline metabolism. This metabolic shift may reflect an adaptive response in cancer cells, favoring specific amino acids to support their growth. Together, these integrated results provide valuable insights into the intricate landscape of tumor development, highlighting the crossroads of immune regulation, cellular structure, and metabolic reprogramming in the tumorigenic process and providing valuable insights into cancer pathology.

Keywords:  Anti-Cancer; Colorectal cancer; Compound; Multi-omics

DOI:  https://doi.org/10.1016/j.bbrc.2024.150598
Anal Chem. 2024 Sep 02.

Polarization of Macrophages in Tumor Microenvironment Using High-Throughput Single-Cell Metabolomics.

Xuesen Hu, Xinlin Liu, Disheng Feng, Tianrun Xu, Hang Li, Chunxiu Hu, Zhizhou Wang, Xinyu Liu, Peiyuan Yin, Xianzhe Shi, Dong Shang, Guowang Xu.

Macrophages consist of a heterogeneous population of functionally distinct cells that participate in many physiological and pathological processes. They exhibit prominent plasticity by changing their different functional phenotypes represented by proinflammatory (M1) and anti-inflammatory (M2) in response to different environmental stimuli. Emerging evidence illustrates the importance of intracellular metabolic pathways in macrophage polarizations and functions. In the tumor microenvironment (TME), macrophages tend to M2 polarization, which promotes tumor growth and leads to adverse physiological effects. Due to the lack of highly specific antigens in M1 and M2 macrophages, significant challenges present in isolating these subtypes from clinical samples or in vitro coculture models of tumor-immune cells. In reverse, the single-cell technique provides the possibility to investigate the factors influencing macrophage polarization in the TME. In this research, we employed inertial microfluidic chip-mass spectrometry (IMC-MS) to conduct single-cell metabolomics analysis of macrophages polarized into the two major phenotypes, respectively, and 213 metabolites were identified in total. Subsequently, differential metabolites between macrophage phenotypes were analyzed using volcano plots and binary logistic regression models. Glutamine was pinpointed as a key metabolite for the M1 and M2 phenotypes. Experimental results from both monoculture and coculture cell models demonstrated that M1 polarization is more reliant on the presence of glutamine in the culture environment than M2 polarization. Glutamine deficiency resulted in failed M1 polarization, while its absence had a less pronounced effect on M2 polarization. Replenishing an appropriate amount of glutamine during the intermediate stages of coculture models significantly enhanced the proportion of M1 polarization and suppressed the growth of tumor cells. This research elucidated glutamine as a key factor influencing macrophage polarization in the TME via single-cell metabolomics based on IMC-MS, offering promising insights and targets for tumor therapies.

DOI: https://doi.org/10.1021/acs.analchem.4c02989
Invest Ophthalmol Vis Sci. 2024 Sep 03. 65(11): 5

Metabolic Phenotyping of Healthy and Diseased Human RPE Cells.

Saira Rizwan, Beverly Toothman, Bo Li, Abbi J Engel, Rayne R Lim, Sheldon Niernberger, Jinyu Lu, Cloe Ratliff, Yinxiao Xiang, Mark Eminhizer, Jennifer R Chao, Jianhai Du.

Purpose: Metabolic defects in the retinal pigment epithelium (RPE) underlie many retinal degenerative diseases. This study aims to identify the nutrient requirements of healthy and diseased human RPE cells.
Methods: We profiled nutrient use of various human RPE cells, including differentiated and dedifferentiated fetal RPE (fRPE), induced pluripotent stem cell-derived RPE (iPSC RPE), Sorsby fundus dystrophy (SFD) patient-derived iPSC RPE, CRISPR-corrected isogenic SFD (cSFD) iPSC RPE, and ARPE-19 cell lines using Biolog Phenotype MicroArray Assays.
Results: Differentiated fRPE cells and healthy iPSC RPE cells can use 51 and 48 nutrients respectively, including sugars, intermediates from glycolysis and tricarboxylic acid (TCA) cycle, fatty acids, ketone bodies, amino acids, and dipeptides. However, when fRPE cells lose their epithelial phenotype through dedifferentiation, nutrient use becomes restricted to 17 nutrients, primarily sugar and glutamine-related amino acids. SFD RPE cells can use 37 nutrients; however, compared to cSFD RPE and healthy iPSC RPE, they are unable to use lactate, some TCA cycle intermediates, and short-chain fatty acids. Nonetheless, they show increased use of branch-chain amino acids (BCAAs) and BCAA-containing dipeptides. Dedifferentiated ARPE-19 cells grown in traditional culture media cannot use lactate and ketone bodies. In contrast, nicotinamide supplementation promotes differentiation toward an epithelial phenotype, restoring the ability to use these nutrients.
Conclusions: Epithelial phenotype confers metabolic flexibility to healthy RPE for using various nutrients. SFD RPE cells have reduced metabolic flexibility, relying on the oxidation of BCAAs. Our findings highlight the potentially important roles of nutrient availability and use in RPE differentiation and diseases.

DOI: https://doi.org/10.1167/iovs.65.11.5
J Biol Chem. 2024 Sep 03. pii: S0021-9258(24)02247-6. [Epub ahead of print] 107746

Perturbations in mitochondrial metabolism associated with defective cardiolipin biosynthesis: An in-organello real-time NMR study.

Antonio J Rua, Wayne Mitchell, Steven M Claypool, Nathan N Alder, Andrei T Alexandrescu.

  Mitochondria are central to cellular metabolism; hence, their dysfunction contributes to a wide array of human diseases. Cardiolipin, the signature phospholipid of the mitochondrion, affects proper cristae morphology, bioenergetic functions, and metabolic reactions carried out in mitochondrial membranes. To match tissue-specific metabolic demands, cardiolipin typically undergoes an acyl tail remodeling process with the final step carried out by the phospholipid-lysophospholipid transacylase tafazzin. Mutations in tafazzin are the primary cause of Barth syndrome. Here, we investigated how defects in cardiolipin biosynthesis and remodeling impacts metabolic flux through the TCA cycle and associated yeast pathways. Nuclear magnetic resonance was used to monitor in real-time the metabolic fate of 13C3-pyruvate in isolated mitochondria from three isogenic yeast strains. We compared mitochondria from a wild-type strain to mitochondria from a Δtaz1 strain that lacks tafazzin and contains lower amounts of unremodeled cardiolipin, and mitochondria from a Δcrd1 strain that lacks cardiolipin synthase and cannot synthesize cardiolipin. We found that the 13C-label from the pyruvate substrate was distributed through twelve metabolites. Several of the metabolites were specific to yeast pathways including branched chain amino acids and fusel alcohol synthesis. While most metabolites showed similar kinetics amongst the different strains, mevalonate concentrations were significantly increased in Δtaz1 mitochondria. Additionally, the kinetic profiles of α-ketoglutarate, as well as NAD+ and NADH measured in separate experiments, displayed significantly lower concentrations for Δtaz1 and Δcrd1 mitochondria at most time points. Taken together, the results show how cardiolipin remodeling influences pyruvate metabolism, tricarboxylic acid cycle flux, and the levels of mitochondrial nucleotides.

Keywords:  3-methylglutaconic acid (3MGA); Barth syndrome (BTHS); Krebs cycle; adenosine triphosphate (ATP); metabolic disease; mitochondrial respiration; nuclear magnetic resonance (NMR); tricarboxylic acid (TCA) cycle

DOI:  https://doi.org/10.1016/j.jbc.2024.107746
Inflammation. 2024 Aug 30.

Metabolomics Reveals Disturbed Amino Acid Metabolism During Different Stages of RA in Collagen-Induced Arthritis Mice.

Xiafeng Zhang, Mengdi Yin, Dingyi Zhang, Dandan Cao, Xiaoxiao Hou, Zhenghao Xu, Chengping Wen, Jia Zhou.

  Rheumatoid arthritis (RA) is an autoimmune disease featured by chronic synovitis and progressive joint damage. Early treatment before the onset of clinical symptoms (also known as the pre-RA stage) may slow or stop the progression of the disease. We sought to discover the dynamic metabolic changes during the evolution of collagen-induced arthritis (CIA) to better characterize the disease stages. Untargeted metabolomics analysis using gas chromatography-mass spectrometry revealed that the metabolic profiles of CIA mice gradually differed from that of the control group with the progression of the disease. During the induction phase, the CIA group showed some metabolic alterations in galactose metabolism, arginine biosynthesis, tricarboxylic acid cycle (TCA cycle), pyruvate metabolism, and starch/sucrose metabolism. During the early inflammatory phase, no joint swelling was observed in CIA mice, and metabolites changed mainly involving amino acid metabolism (arginine biosynthesis, arginine/proline metabolism, phenylalanine/tyrosine/tryptophan biosynthesis), and glutathione metabolism. During the peak inflammatory phase, severe arthritis symptoms were observed in CIA mice, and there were more extensive metabolic alterations in valine/leucine/isoleucine biosynthesis, phenylalanine/tyrosine/tryptophan biosynthesis, TCA cycle, galactose metabolism, and arginine biosynthesis. Moreover, the reduction of specific amino acids, such as glycine, serine, and proline, during the early stages may result in an imbalance in macrophage polarization and enhance the inflammatory response in CIA mice. Our study confirmed that specific perturbations in amino acid metabolism have occurred in CIA mice prior to the onset of joint symptoms, which may be related to autoimmune disorders. The findings could provide insights into the metabolic mechanism and the diagnosis of pre-RA.

Keywords:  Collagen-induced arthritis; Early diagnosis; Early stages; Metabolomics; Rheumatoid arthritis

DOI:  https://doi.org/10.1007/s10753-024-02123-1
Mol Immunol. 2024 Aug 29. pii: S0161-5890(24)00160-3. [Epub ahead of print]174 57-68

Acidity induces durable enhancement of Treg cell suppressive functions for tumor immune evasion.

Nikita L Mani, Samuel E Weinberg, Shuvam Chaudhuri, Elena Montauti, Amy Tang, Radhika Iyer, Deyu Fang.

  The microenvironment within solid tumors often becomes acidic due to various factors associated with abnormal metabolism and cellular activities, including increased lactate production as a result of dysregulated tumor glycolysis. Recently, we have identified multiple tumor microenvironment (TME) factors that potentiate regulatory T (Treg) cell function in evading anti-tumor immunosurveillance. Despite the strong correlation between lactate and acidity, the potential roles of acidity in intratumoral Treg cell adaptation and underlying molecular mechanisms have gone largely unstudied. In this study, we demonstrate that acidity significantly enhances immunosuppressive functions of nTreg cells, but not iTreg cells, without altering the expression of either FoxP3 or the cell surface receptors CD25, CTLA4, or GITR in these cells. Surprisingly, the addition of lactate, often considered a major contributor to increased acidity of the TME, completely abolished the acidity-induced enhancement of nTreg suppressive functions. Consistently, metabolic flux analyses showed elevated basal mitochondrial respiratory capacity and ATP-coupled respiration in acidity-treated nTreg cells without altering glycolytic capacity. Genome-wide transcriptome and metabolomics analyses revealed alterations in multiple metabolic pathways, particularly the one-carbon folate metabolism pathway, with reduced SAM, folate, and glutathione, in nTreg cells exposed to low pH conditions. Addition of a one-carbon metabolic contributor, formate, diminished the acidity-induced enhancement in nTreg cell suppressive functions, but neither SAM nor glutathione could reverse the phenotype. Remarkably, in vitro transient treatment of nTreg cells resulted in sustained enhancement of their functions, as evidenced by more vigorous tumor growth observed in mice adoptively receiving acidity-treated nTreg cells. Further analysis of intratumoral infiltrated T cells confirmed a significant reduction in CD8+ T cell frequency and their granzyme B production. In summary, our study elucidates how acidity-mediated metabolic reprogramming leads to sustained Treg-mediated tumor immune evasion.

Keywords:  Acidity; Formate; Lactate; Oxidative phosphorylation; Suppression; T(reg) cells

DOI:  https://doi.org/10.1016/j.molimm.2024.08.004
Food Chem Toxicol. 2024 Aug 27. pii: S0278-6915(24)00519-2. [Epub ahead of print]193 114953

Mitochondrial damage precedes the changes of glutathione metabolism in CdCl2 treated neuronal SH-SY5Y cells.

Pavlina Nyvltova, Jan Capek, Jiri Handl, Filip Petira, Erika Rousarova, Lenka Ticha, Stepanka Jelinkova, Tomas Rousar.

  Cadmium crosses the blood-brain barrier inducing damage to neurons. Cell impairment is predominantly linked to oxidative stress and glutathione (GSH) depletion. On the other hand, several reports have described an increase of GSH levels in neuronal cells after CdCl2 exposure. Therefore, the aim of the present report was to investigate the relation between changes in GSH levels and mitochondrial damage in neuronal cells after CdCl2 treatment. To characterize neuronal impairment after CdCl2 treatment (0-200 μM) for 1-48 h, we used the SH-SY5Y cell line. We analyzed GSH metabolism and determined mitochondrial activity using high-resolution respirometry. CdCl2 treatment induced both the decreases and increases of GSH levels in SH-SY5Y cells. GSH concentration was significantly increased in cells incubated with up to 50 μM CdCl2 but only 100 μM CdCl2 induced GSH depletion linked to increased ROS production. The overexpression of proteins involved in GSH synthesis increased in response to 50 and 100 μM CdCl2 after 6 h. Finally, strong mitochondrial impairment was detected even in 50 μM CdCl2 treated cells after 24 h. We conclude that a significant decrease in mitochondrial activity can be observed in 50 μM CdCl2 even without the occurrence of GSH depletion in SH-SY5Y cells.

Keywords:  Cadmium toxicity; Glutathione depletion; Mitochondrial damage; Neuronal cells; Oxidative stress

DOI:  https://doi.org/10.1016/j.fct.2024.114953
Transl Oncol. 2024 Sep 02. pii: S1936-5233(24)00239-0. [Epub ahead of print]49 102112

HADH suppresses clear cell renal cell carcinoma progression through reduced NRF2-dependent glutathione synthesis.

Changbin Chu, Shangjing Liu, Zhiting He, Mingjun Wu, Jing Xia, Hongxiang Zeng, Wenhua Xie, Rui Cheng, Xueya Zhao, Xi Li.

   BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a serious threat to human life. It is very important to clarify the pathogenesis of ccRCC. In this study we evaluated the clinical value of HADH and explored its role and mechanism in the malignant progression of ccRCC.
METHODS: HADH expression and its relationship with prognosis were analyzed using bioinformatics database. RT-PCR, Western blot and immunohistochemistry were used to examine the expression of HADH in ccRCC tissues and tissue microarrays. To examine the cell proliferation, apoptosis, migration and invasion ability, ccRCC cells with HADH overexpressed were constructed. Xenograft experiments were performed to determine the role of HADH. Non-target metabolomics was applied to explore the potential metabolic pathway by which HADH inhibited ccRCC progression. Plasmid pcDNA3.1-NRF2 was used to confirm whether HADH inhibited the process of ccRCC cells through NRF2-related glutathione (GSH) synthesis.
RESULTS: Bioinformatics database analysis showed that HADH expression was significantly decreased in ccRCC tissues, and its low expression predicted a poor prognosis. Both ccRCC tissues and tissue microarrays exhibited a significantly decreased HADH level compared with adjacent normal renal tissues. HADH overexpression inhibited the malignant behaviors of ccRCC cells. Furthermore, HADH overexpression attenuated GSH synthesis and induced oxidative stress damage. Exogenously increased NRF2 effectively attenuated the inhibitive effect of HADH overexpression on ccRCC cells.
CONCLUSION: Our data revealed that HADH suppressed the malignant behaviors of ccRCC cells by attenuating GSH synthesis through inhibition of NRF2 nuclear translocation, and HADH might be a novel therapeutic target for ccRCC treatment.

Keywords:  Clear cell renal cell carcinoma; Glutathione synthesis; HADH; NRF2; Non-target metabolomics

DOI:  https://doi.org/10.1016/j.tranon.2024.102112
Nutrients. 2024 Aug 18. pii: 2753. [Epub ahead of print]16(16):

The Role of S-Glutathionylation in Health and Disease: A Bird's Eye View.

Luca Federici, Michele Masulli, Vincenzo De Laurenzi, Nerino Allocati.

  Protein glutathionylation is a reversible post-translational modification that involves the attachment of glutathione to cysteine residues. It plays a role in the regulation of several cellular processes and protection against oxidative damage. Glutathionylation (GS-ylation) modulates protein function, inhibits or enhances enzymatic activity, maintains redox homeostasis, and shields several proteins from irreversible oxidative stress. Aberrant GS-ylation patterns are thus implicated in various diseases, particularly those associated with oxidative stress and inflammation, such as cardiovascular diseases, neurodegenerative disorders, cancer, and many others. Research in the recent years has highlighted the potential to manipulate protein GS-ylation for therapeutic purposes with strategies that imply both its enhancement and inhibition according to different cases. Moreover, it has become increasingly evident that monitoring the GS-ylation status of selected proteins offers diagnostic potential in different diseases. In this review, we try to summarize recent research in the field with a focus on our current understanding of the molecular mechanisms related to aberrant protein GS-ylation.

Keywords:  GS-ylation; GSH; S-glutathionylation; glutathione; oxidative stress; post-translational modification

DOI:  https://doi.org/10.3390/nu16162753
Biomark Res. 2024 Sep 02. 12(1): 94

The solute carrier transporters (SLCs) family in nutrient metabolism and ferroptosis.

Li-Li Sun, Hai-Yan He, Wei Li, Wei-Lin Jin, Yi-Ju Wei.

  Ferroptosis is a novel form of programmed cell death caused by damage to lipid membranes due to the accumulation of lipid peroxides in response to various stimuli, such as high levels of iron, oxidative stress, metabolic disturbance, etc. Sugar, lipid, amino acid, and iron metabolism are crucial in regulating ferroptosis. The solute carrier transporters (SLCs) family, known as the "metabolic gating" of cells, is responsible for transporting intracellular nutrients and metabolites. Recent studies have highlighted the significant role of SLCs family members in ferroptosis by controlling the transport of various nutrients. Here, we summarized the function and mechanism of SLCs in ferroptosis regulated by ion, metabolic control of nutrients, and multiple signaling pathways, with a focus on SLC-related transporters that primarily transport five significant components: glucose, amino acid, lipid, trace metal ion, and other ion. Furthermore, the potential clinical applications of targeting SLCs with ferroptosis inducers for various diseases, including tumors, are discussed. Overall, this paper delves into the novel roles of the SLCs family in ferroptosis, aiming to enhance our understanding of the regulatory mechanisms of ferroptosis and identify new therapeutic targets for clinical applications.

Keywords:  Ferroptosis; Glucose; Lipid; Metal ion; Solute carrier transporters

DOI:  https://doi.org/10.1186/s40364-024-00645-2
Biomark Res. 2024 Sep 03. 12(1): 96

Metabolic reprogramming and immune evasion: the interplay in the tumor microenvironment.

Haixia Zhang, Shizhen Li, Dan Wang, Siyang Liu, Tengfei Xiao, Wangning Gu, Hongmin Yang, Hui Wang, Minghua Yang, Pan Chen.

  Tumor cells possess complex immune evasion mechanisms to evade immune system attacks, primarily through metabolic reprogramming, which significantly alters the tumor microenvironment (TME) to modulate immune cell functions. When a tumor is sufficiently immunogenic, it can activate cytotoxic T-cells to target and destroy it. However, tumors adapt by manipulating their metabolic pathways, particularly glucose, amino acid, and lipid metabolism, to create an immunosuppressive TME that promotes immune escape. These metabolic alterations impact the function and differentiation of non-tumor cells within the TME, such as inhibiting effector T-cell activity while expanding regulatory T-cells and myeloid-derived suppressor cells. Additionally, these changes lead to an imbalance in cytokine and chemokine secretion, further enhancing the immunosuppressive landscape. Emerging research is increasingly focusing on the regulatory roles of non-tumor cells within the TME, evaluating how their reprogrammed glucose, amino acid, and lipid metabolism influence their functional changes and ultimately aid in tumor immune evasion. Despite our incomplete understanding of the intricate metabolic interactions between tumor and non-tumor cells, the connection between these elements presents significant challenges for cancer immunotherapy. This review highlights the impact of altered glucose, amino acid, and lipid metabolism in the TME on the metabolism and function of non-tumor cells, providing new insights that could facilitate the development of novel cancer immunotherapies.

Keywords:  Immune evasion; Immunotherapy; Metabolic reprogramming; Tumor microenvironment

DOI:  https://doi.org/10.1186/s40364-024-00646-1
Spectrochim Acta A Mol Biomol Spectrosc. 2024 Aug 29. pii: S1386-1425(24)01218-6. [Epub ahead of print]325 125052

A glutathione responsive photosensitizer based on hypocrellin B for photodynamic therapy.

Zhe Yu, Tian Liu, Xiuli Zheng, Yanping Wang, Jie Sha, Lin Shan, Tong Mu, Wenjun Zhang, Chun Sing Lee, Weimin Liu, Pengfei Wang.

  As a typical natural photosensitizer, hypocrellin B (HB) offers the advantages of high molar extinction coefficient, high phototoxicity, low dark toxicity, and fast metabolism in vivo. However, the lack of tumor specificity hinders its clinical applications. Herein, we designed and synthesized a glutathione (GSH) responsive photosensitizer based on HB. The 7 - nitro - 2,1,3 - benzoxadiazole (NBD) covalently connected to HB not only served as a fluorescence quenching group but also as a GSH activating group. The photosensitizer HB-NBD showed almost no fluorescence and singlet oxygen generation as a result of the photoinduced electron transfer between HB and NBD. The designed photosensitizer HB-NBD can be activated by GSH in solutions and cancer cells, and then obtain recuperative fluorescence and photosensitive activity.

Keywords:  Cancer cells; Glutathione; Hypocrellin B; Photocytotoxicity; Photodynamic therapy

DOI:  https://doi.org/10.1016/j.saa.2024.125052