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Ha CP, Hua TNM, Vo VTA, Om J, Han S, Cha SK, Park KS, Jeong Y. Humanin activates integrin αV-TGFβ axis and leads to glioblastoma progression. Cell Death Dis 2024; 15:464. [PMID: 38942749 PMCID: PMC11213926 DOI: 10.1038/s41419-024-06790-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 05/28/2024] [Accepted: 05/29/2024] [Indexed: 06/30/2024]
Abstract
The role of mitochondria peptides in the spreading of glioblastoma remains poorly understood. In this study, we investigated the mechanism underlying intracranial glioblastoma progression. Our findings demonstrate that the mitochondria-derived peptide, humanin, plays a significant role in enhancing glioblastoma progression through the intratumoral activation of the integrin alpha V (ITGAV)-TGF beta (TGFβ) signaling axis. In glioblastoma tissues, humanin showed a significant upregulation in the tumor area compared to the corresponding normal region. Utilizing multiple in vitro pharmacological and genetic approaches, we observed that humanin activates the ITGAV pathway, leading to cellular attachment and filopodia formation. This process aids the subsequent migration and invasion of attached glioblastoma cells through intracellular TGFβR signaling activation. In addition, our in vivo orthotopic glioblastoma model provides further support for the pro-tumoral function of humanin. We observed a correlation between poor survival and aggressive invasiveness in the humanin-treated group, with noticeable tumor protrusions and induced angiogenesis compared to the control. Intriguingly, the in vivo effect of humanin on glioblastoma was significantly reduced by the treatment of TGFBR1 inhibitor. To strengthen these findings, public database analysis revealed a significant association between genes in the ITGAV-TGFβR axis and poor prognosis in glioblastoma patients. These results collectively highlight humanin as a pro-tumoral factor, making it a promising biological target for treating glioblastoma.
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Affiliation(s)
- Cuong P Ha
- Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
| | - Tuyen N M Hua
- Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Department of Pharmacology - Clinical Pharmacy, Faculty of Pharmacy, Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
| | - Vu T A Vo
- Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
| | - Jiyeon Om
- Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
| | - Sangwon Han
- Department of Ophthalmology, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
| | - Seung-Kuy Cha
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Department of Physiology, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Institutes of Lifestyle Medicine, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
- Mitochondrial Medicine, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea
| | - Kyu-Sang Park
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Department of Physiology, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Institutes of Lifestyle Medicine, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Mitochondrial Medicine, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
| | - Yangsik Jeong
- Department of Biochemistry, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Department of Global Medical Science, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Mitohormesis Research Center, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Institutes of Lifestyle Medicine, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
- Mitochondrial Medicine, Wonju College of Medicine, Yonsei University, Wonju, 26426, Republic of Korea.
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2
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Aleshina YA, Aleshin VA. Evolutionary Changes in Primate Glutamate Dehydrogenases 1 and 2 Influence the Protein Regulation by Ligands, Targeting and Posttranslational Modifications. Int J Mol Sci 2024; 25:4341. [PMID: 38673928 PMCID: PMC11050691 DOI: 10.3390/ijms25084341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 04/10/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
There are two paralogs of glutamate dehydrogenase (GDH) in humans encoded by the GLUD1 and GLUD2 genes as a result of a recent retroposition during the evolution of primates. The two human GDHs possess significantly different regulation by allosteric ligands, which is not fully characterized at the structural level. Recent advances in identification of the GDH ligand binding sites provide a deeper perspective on the significance of the accumulated substitutions within the two GDH paralogs. In this review, we describe the evolution of GLUD1 and GLUD2 after the duplication event in primates using the accumulated sequencing and structural data. A new gibbon GLUD2 sequence questions the indispensability of ancestral R496S and G509A mutations for GLUD2 irresponsiveness to GTP, providing an alternative with potentially similar regulatory features. The data of both GLUD1 and GLUD2 evolution not only confirm substitutions enhancing GLUD2 mitochondrial targeting, but also reveal a conserved mutation in ape GLUD1 mitochondrial targeting sequence that likely reduces its transport to mitochondria. Moreover, the information of GDH interactors, posttranslational modification and subcellular localization are provided for better understanding of the GDH mutations. Medically significant point mutations causing deregulation of GDH are considered from the structural and regulatory point of view.
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Affiliation(s)
- Yulia A. Aleshina
- Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov First Moscow State Medical University, 119435 Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Vasily A. Aleshin
- Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
- Department of Biochemistry, Sechenov First Moscow State Medical University, 119048 Moscow, Russia
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3
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Moedas MF, Simões RJM, Silva MFB. Mitochondrial targets in hyperammonemia: Addressing urea cycle function to improve drug therapies. Biochem Pharmacol 2024; 222:116034. [PMID: 38307136 DOI: 10.1016/j.bcp.2024.116034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 12/27/2023] [Accepted: 01/25/2024] [Indexed: 02/04/2024]
Abstract
The urea cycle (UC) is a critically important metabolic process for the disposal of nitrogen (ammonia) produced by amino acids catabolism. The impairment of this liver-specific pathway induced either by primary genetic defects or by secondary causes, namely those associated with hepatic disease or drug administration, may result in serious clinical consequences. Urea cycle disorders (UCD) and certain organic acidurias are the major groups of inherited rare diseases manifested with hyperammonemia (HA) with UC dysregulation. Importantly, several commonly prescribed drugs, including antiepileptics in monotherapy or polytherapy from carbamazepine to valproic acid or specific antineoplastic agents such as asparaginase or 5-fluorouracil may be associated with HA by mechanisms not fully elucidated. HA, disclosing an imbalance between ammoniagenesis and ammonia disposal via the UC, can evolve to encephalopathy which may lead to significant morbidity and central nervous system damage. This review will focus on biochemical mechanisms related with HA emphasizing some poorly understood perspectives behind the disruption of the UC and mitochondrial energy metabolism, namely: i) changes in acetyl-CoA or NAD+ levels in subcellular compartments; ii) post-translational modifications of key UC-related enzymes, namely acetylation, potentially affecting their catalytic activity; iii) the mitochondrial sirtuins-mediated role in ureagenesis. Moreover, the main UCD associated with HA will be summarized to highlight the relevance of investigating possible genetic mutations to account for unexpected HA during certain pharmacological therapies. The ammonia-induced effects should be avoided or overcome as part of safer therapeutic strategies to protect patients under treatment with drugs that may be potentially associated with HA.
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Affiliation(s)
- Marco F Moedas
- Research Institute for Medicines-iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal; Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden; Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Ricardo J M Simões
- Research Institute for Medicines-iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Margarida F B Silva
- Research Institute for Medicines-iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal.
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4
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Cholico GN, Fling RR, Sink WJ, Nault R, Zacharewski T. Inhibition of the urea cycle by the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin increases serum ammonia levels in mice. J Biol Chem 2024; 300:105500. [PMID: 38013089 PMCID: PMC10731612 DOI: 10.1016/j.jbc.2023.105500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/26/2023] [Accepted: 11/18/2023] [Indexed: 11/29/2023] Open
Abstract
The aryl hydrocarbon receptor is a ligand-activated transcription factor known for mediating the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds. TCDD induces nonalcoholic fatty liver disease (NAFLD)-like pathologies including simple steatosis that can progress to steatohepatitis with fibrosis and bile duct proliferation in male mice. Dose-dependent progression of steatosis to steatohepatitis with fibrosis by TCDD has been associated with metabolic reprogramming, including the disruption of amino acid metabolism. Here, we used targeted metabolomic analysis to reveal dose-dependent changes in the level of ten serum and eleven hepatic amino acids in mice upon treatment with TCDD. Bulk RNA-seq and protein analysis showed TCDD repressed CPS1, OTS, ASS1, ASL, and GLUL, all of which are associated with the urea cycle and glutamine biosynthesis. Urea and glutamine are end products of the detoxification and excretion of ammonia, a toxic byproduct of amino acid catabolism. Furthermore, we found that the catalytic activity of OTC, a rate-limiting step in the urea cycle was also dose dependently repressed. These results are consistent with an increase in circulating ammonia. Collectively, the repression of the urea and glutamate-glutamine cycles increased circulating ammonia levels and the toxicity of TCDD.
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Affiliation(s)
- Giovan N Cholico
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Russell R Fling
- Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA; Microbiology & Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Warren J Sink
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Rance Nault
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA
| | - Tim Zacharewski
- Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Institute for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA.
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5
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Wang XP, Sun SP, Li YX, Wang L, Dong DJ, Wang JX, Zhao XF. 20-hydroxyecdysone reprograms amino acid metabolism to support the metamorphic development of Helicoverpa armigera. Cell Rep 2023; 42:112644. [PMID: 37310862 DOI: 10.1016/j.celrep.2023.112644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 04/16/2023] [Accepted: 05/27/2023] [Indexed: 06/15/2023] Open
Abstract
Amino acid metabolism is regulated according to nutrient conditions; however, the mechanism is not fully understood. Using the holometabolous insect cotton bollworm (Helicoverpa armigera) as a model, we report that hemolymph metabolites are greatly changed from the feeding larvae to the wandering larvae and to pupae. Arginine, alpha-ketoglutarate (α-KG), and glutamate (Glu) are identified as marker metabolites of feeding larvae, wandering larvae, and pupae, respectively. Arginine level is decreased by 20-hydroxyecdysone (20E) regulation via repression of argininosuccinate synthetase (Ass) expression and upregulation of arginase (Arg) expression during metamorphosis. α-KG is transformed from Glu by glutamate dehydrogenase (GDH) in larval midgut, which is repressed by 20E. The α-KG is then transformed to Glu by GDH-like in pupal fat body, which is upregulated by 20E. Thus, 20E reprogrammed amino acid metabolism during metamorphosis by regulating gene expression in a stage- and tissue-specific manner to support insect metamorphic development.
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Affiliation(s)
- Xiao-Pei Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Shu-Peng Sun
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Yan-Xue Li
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Lin Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Du-Juan Dong
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Jin-Xing Wang
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China
| | - Xiao-Fan Zhao
- Shandong Provincial Key Laboratory of Animal Cells and Developmental Biology, School of Life Sciences, Shandong University, Qingdao 266237, China.
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Tang Q, Li W, Ren Z, Ding Q, Peng X, Tang Z, Pang J, Xu Y, Sun Z. Different Fatty Acid Supplementation in Low-Protein Diets Regulate Nutrient Utilization and Lipid and Amino Acid Metabolism in Weaned Pigs Model. Int J Mol Sci 2023; 24:ijms24108501. [PMID: 37239844 DOI: 10.3390/ijms24108501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/21/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023] Open
Abstract
This study was conducted to evaluate the effects of a low-protein (LP) diet supplemented with sodium butyrate (SB), medium-chain fatty acids (MCFAs) and n-3 polyunsaturated fatty acids (PUFAs) on nutrient utilization and lipid and amino acid metabolism in weaned pigs. A total of 120 Duroc × Landrace × Yorkshire pigs (initial body weight: 7.93 ± 0.65 kg) were randomly assigned to five dietary treatments, including the control diet (CON), LP diet, LP + 0.2% SB diet (LP + SB), LP + 0.2% MCFA diet (LP + MCFA) and LP + 0.2% n-3 PUFA diet (LP + PUFA). The results show that the LP + MCFA diet increased (p < 0.05) the digestibility of dry matter and total P in pigs compared with the CON and LP diets. In the liver of the pigs, the metabolites involved in sugar metabolism and oxidative phosphorylation significantly changed with the LP diet compared with the CON diet. Compared with the LP diet, the altered metabolites in the liver of the pigs fed with the LP + SB diet were mainly associated with sugar metabolism and pyrimidine metabolism; the altered metabolites in the liver of pigs fed with the LP + MCFA and LP + PUFA diets were mainly associated with lipid metabolism and amino acid metabolism. In addition, the LP + PUFA diet increased (p < 0.05) the concentration of glutamate dehydrogenase in the liver of pigs compared with the LP diet. Furthermore, the LP + MCFA and LP + PUFA diets increased (p < 0.05) the mRNA abundance of sterol regulatory element-binding protein 1 and acetyl-CoA carboxylase in the liver compared with the CON diet. The LP + PUFA diet increased (p < 0.05) mRNA abundances of fatty acid synthase in the liver compared with the CON and LP diets. Collectively, the LP diet supplemented with MCFAs improved nutrient digestibility, and the LP diet supplemented with MCFAs and n-3 PUFAs promoted lipid and amino acid metabolisms.
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Affiliation(s)
- Qingsong Tang
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Wenxue Li
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Zhongxiang Ren
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Qi Ding
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Xie Peng
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Zhiru Tang
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Jiaman Pang
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Yetong Xu
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
| | - Zhihong Sun
- Laboratory for Bio-Feed and Molecular Nutrition, College of Animal Science and Technology, Southwest University, Chongqing 400715, China
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Chuang HJ, Chiu L, Yan JJ, Chang CY, Tang YH, Chou MY, Yu HT, Hwang PP. Responses of medaka (Oryzias latipes) ammonia production and excretion to overcome acidified environments. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130539. [PMID: 36502720 DOI: 10.1016/j.jhazmat.2022.130539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/28/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Anthropogenic acidification of water is an on-going environmental disaster for freshwater fishes. Fishes rely on ammonia excretion to eliminate the excess acid and mitigate the harmful effects; however, it remains largely unknown how ammoniagenesis occurs and is coordinated with ammonia excretion upon acidic stress. Medaka (Oryzias latipes) was used to examine the effects of acidic stress on ammonia production and excretion. We reveal an undiscovered ammonia-producing cell type that is rich in glutaminase (GLS) and located adjacent to the ammonia-excreting ionocytes, Na+/H+ exchanger (NHE) cells, in the gills. The gills, comparing with other ammoniagenetic organs, is the quickest to respond to the acidic stress by triggering GLS-dependent ammonia production. The unique division of labor between GLS and NHE cells in the gills allows medaka to simultaneously upregulate GLS activity and ammonia excretion shortly after exposure to acidic environments. Pharmacological experiment with a GLS inhibitor abolished the activated ammonia excretion, further suggesting the essential role of the unique feature in the responses to acidic stress. Our study shades light on a novel physiological mechanism to timely and efficiently mitigate adverse effects of acidification, providing a new way to assess the impact of on-going environmental acidification on fish.
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Affiliation(s)
- Hsin-Ju Chuang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan; Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Ling Chiu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan; Institute of Oceanography, National Taiwan University, Taipei 10617, Taiwan
| | - Jia-Jiun Yan
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Chun-Yung Chang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Yu-Hsin Tang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Ming-Yi Chou
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Hon-Tsen Yu
- Department of Life Science, National Taiwan University, Taipei 10617, Taiwan
| | - Pung-Pung Hwang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan.
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8
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Aliakbarzadeh F, Rafiee M, Khodagholi F, Khorramizadeh MR, Manouchehri H, Eslami A, Sayehmiri F, Mohseni-Bandpei A. Adverse effects of polystyrene nanoplastic and its binary mixtures with nonylphenol on zebrafish nervous system: From oxidative stress to impaired neurotransmitter system. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 317:120587. [PMID: 36336178 DOI: 10.1016/j.envpol.2022.120587] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
Micro(nano)plastics generally co-exist with other chemicals in the environment, resulting in inevitable interaction and combined toxic effects on biota. Nevertheless, little is known regarding the interaction of nanoplastics (NPs) with other co-occurring insults. Hereby, we investigated single and combined effects of chronic exposure (45 days) to polystyrene nanoplastic particulates (PS-NPs) and nonylphenol (4-NP) on zebrafish nervous system. Multiple biomarkers concerning with oxidative-stress [catalase (CAT) activity and reduced glutathione (GSH) level], cholinergic system [Acetylcholinesterase (AchE) activity], glutamatergic system [glutamine synthetase (GS) and glutamate dehydrogenase (GDH) activities], energy metabolism [a-ketoglutarate dehydrogenase (a-KGDH) activity], and histological alterations were assessed. Both single and binary exposure to PS-NPs and 4-NP induced oxidative stress through reducing CAT activity and GSH level, in which a more sever effect was noticed in combined exposure. The AchE activity was significantly inhibited only in single treatment groups demonstrating antagonistic interaction between PS-NPs and 4-NP. Effects on GS activity was also alleviated in binary exposure as compared with single exposure to each contaminant. In addition, an increase in GDH activity was noticed in PS-NPs at 10 and 100 μg/L, and simultaneous presence of PS-NPs and 4-NP with a greater response were observed in combined treatments. PS-NPs and 4-NP either in separate or binary mixtures disrupted energy metabolism by deficiency of α-KGDH activity; however, co-exposure to PS-NPs and 4-NP induced more intense adverse impacts on this parameter. Furthermore, histological analysis revealed that 4-NP and PS-NPs, alone or in combination, reduced neural cells. These findings provide new insight into the neurotoxic effects of binary exposure to PS-NPs and 4-NP at environmentally relevant concentrations. Overall, our findings raise concerns about the presence and toxicity of nano-scale plastic particulates and highlight the importance of investigating the interaction of Micro(nano)plastics with other environmental irritants.
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Affiliation(s)
- Faezeh Aliakbarzadeh
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Air Quality and Climate Change Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Rafiee
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Air Quality and Climate Change Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fariba Khodagholi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Khorramizadeh
- Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, and Zebra Fish Core Facility (ZFIN ID: ZDB-LAB-190117-2), Endocrinology and Metabolism Research Institute, Tehran University of Medical Science, Tehran, Iran
| | - Hamed Manouchehri
- Department of Aquaculture Science, Babol Branch, Islamic Azad University, Babol, Iran
| | - Akbar Eslami
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Environmental and Occupational Hazards Control Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Sayehmiri
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Anoushiravan Mohseni-Bandpei
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Air Quality and Climate Change Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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9
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Zukov RA, Slepov EV, Kurtasova LM, Inzhevatkin EV. [Lymphocytes enzymatic status and peripheral blood neutrophils oxygen-dependent metabolism in patients with renal cancer]. BIOMEDITSINSKAIA KHIMIIA 2022; 68:470-476. [PMID: 36573413 DOI: 10.18097/pbmc20226806470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The immune system, one of the most important homeostatic organism systems, is actively involved in the protection against malignant tumors. The earliest sighs of immune homeostasis disorders should be invetigated at the cellular level, because of cell functional manifestations depend on the state of intracellular metabolic reactions. The study of lymphocyte NAD(P)-dependent dehydrogenases activity and peripheral blood neutrophils oxygen-dependent metabolism in patients with renal cellular carcinoma (RCC) showed a decrease in the intensity of ribose-5-phosphate and NADH-dependent synthetic processes, inhibition of terminal reactions of glycolysis. Altered activities of the studied enzymes favor an increase in outflow of intermediates of the Krebs cycle on the reaction of amino acid metabolism in peripheral blood lymphocytes. Radical nephrectomy was accompanied by increased activity of glycolysis. The basal level chemiluminescent of peripheral neutrophils of RCC patients response was higher both before and after operations. Stimulation of neutrophils by opsonized zymosan in vitro leads to increase in oxidative metabolism activity, most in 14 days after surgery period. Before and 30 days after surgery, adaptive metabolic capabilities of neutrophilic granulocytes decreased.
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Affiliation(s)
- R A Zukov
- Prof. V.F. Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia; A.I. Kryzhanovsky Krasnoyarsk Regional Clinical Oncology Center, Krasnoyarsk, Russia
| | - E V Slepov
- A.I. Kryzhanovsky Krasnoyarsk Regional Clinical Oncology Center, Krasnoyarsk, Russia
| | - L M Kurtasova
- Prof. V.F. Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia
| | - E V Inzhevatkin
- Prof. V.F. Voino-Yasenetsky Krasnoyarsk State Medical University, Krasnoyarsk, Russia; International Scientific Center of Extremal Organism State Research, Federal Research Center Krasnoyarsk Science Center, Siberian Division of the Russian Academy of Sciences, Krasnoyarsk, Russia
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10
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Wei P, Bott AJ, Cluntun AA, Morgan JT, Cunningham CN, Schell JC, Ouyang Y, Ficarro SB, Marto JA, Danial NN, DeBerardinis RJ, Rutter J. Mitochondrial pyruvate supports lymphoma proliferation by fueling a glutamate pyruvate transaminase 2-dependent glutaminolysis pathway. SCIENCE ADVANCES 2022; 8:eabq0117. [PMID: 36179030 PMCID: PMC9524954 DOI: 10.1126/sciadv.abq0117] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 08/04/2022] [Indexed: 06/14/2023]
Abstract
The fate of pyruvate is a defining feature in many cell types. One major fate is mitochondrial entry via the mitochondrial pyruvate carrier (MPC). We found that diffuse large B cell lymphomas (DLBCLs) consume mitochondrial pyruvate via glutamate-pyruvate transaminase 2 to enable α-ketoglutarate production as part of glutaminolysis. This led us to discover that glutamine exceeds pyruvate as a carbon source for the tricarboxylic acid cycle in DLBCLs. As a result, MPC inhibition led to decreased glutaminolysis in DLBCLs, opposite to previous observations in other cell types. We also found that MPC inhibition or genetic depletion decreased DLBCL proliferation in an extracellular matrix (ECM)-like environment and xenografts, but not in a suspension environment. Moreover, the metabolic profile of DLBCL cells in ECM is markedly different from cells in a suspension environment. Thus, we conclude that the synergistic consumption and assimilation of glutamine and pyruvate enables DLBCL proliferation in an extracellular environment-dependent manner.
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Affiliation(s)
- Peng Wei
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Alex J. Bott
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Ahmad A. Cluntun
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jeffrey T. Morgan
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Corey N. Cunningham
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - John C. Schell
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Yeyun Ouyang
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Scott B. Ficarro
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Blais Proteomics Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Jarrod A. Marto
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Blais Proteomics Center, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Nika N. Danial
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Ralph J. DeBerardinis
- Children’s Medical Center Research Institute, University of Texas (UT) Southwestern Medical Center, Dallas, TX 75390, USA
- Howard Hughes Medical Institute, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jared Rutter
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
- Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
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11
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Bian Y, Hou W, Chen X, Fang J, Xu N, Ruan BH. Glutamate Dehydrogenase as a Promising Target for Hyperinsulinism Hyperammonemia Syndrome Therapy. Curr Med Chem 2021; 29:2652-2672. [PMID: 34525914 DOI: 10.2174/0929867328666210825105342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 11/22/2022]
Abstract
Hyperinsulinism-hyperammonemia syndrome (HHS) is a rare disease characterized by recurrent hypoglycemia and persistent elevation of plasma ammonia, and it can lead to severe epilepsy and permanent brain damage. It has been demonstrated that functional mutations of glutamate dehydrogenase (GDH), an enzyme in the mitochondrial matrix, are responsible for the HHS. Thus, GDH has become a promising target for the small molecule therapeutic intervention of HHS. Several medicinal chemistry studies are currently aimed at GDH, however, to date, none of the compounds reported has been entered clinical trials. This perspective summarizes the progress in the discovery and development of GDH inhibitors, including the pathogenesis of HHS, potential binding sites, screening methods, and research models. Future therapeutic perspectives are offered to provide a reference for discovering potent GDH modulators and encourage additional research that will provide more comprehensive guidance for drug development.
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Affiliation(s)
- Yunfei Bian
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hantgzhou 310014. China
| | - Wei Hou
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hantgzhou 310014. China
| | - Xinrou Chen
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hantgzhou 310014. China
| | - Jinzhang Fang
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hantgzhou 310014. China
| | - Ning Xu
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hantgzhou 310014. China
| | - Benfang Helen Ruan
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Hantgzhou 310014. China
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12
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Yao K, Liu H, Yin J, Yuan J, Tao H. Synthetic lethality and synergetic effect: the effective strategies for therapy of IDH-mutated cancers. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:263. [PMID: 34425876 PMCID: PMC8383362 DOI: 10.1186/s13046-021-02054-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 07/28/2021] [Indexed: 12/23/2022]
Abstract
Mutant isocitrate dehydrogenase 1/2 (mIDH1/2) gain a novel function for the conversion of α-ketoglutarate (α-KG) to oncometabolite R-2-hydroxyglutarate (R-2-HG). Two molecular entities namely enasidenib (AG-221) and ivosidenib (AG-120) targeting mIDH2 and mIDH1 respectively, have already been approved by FDA for the treatment of relapsed/refractory acute myeloid leukemia (R/R AML). However, the low responses, drug-related adverse effects, and most significantly, the clinically-acquired resistance of AG-221 and AG-120 has shown great influence on their clinical application. Therefore, searching for novel therapeutic strategies to enhance tumor sensitivity, reduce drug-related side effects, and overcome drug resistance have opened a new research field for defeating IDH-mutated cancers. As the effective methods, synthetic lethal interactions and synergetic therapies are extensively investigated in recent years for the cure of different cancers. In this review, the molecules displaying synergetic effects with mIDH1/2 inhibitors, as well as the targets showing relevant synthetic lethal interactions with mIDH1/2 are described emphatically. On these foundations, we discuss the opportunities and challenges for translating these strategies into clinic to combat the defects of existing IDH inhibitors.
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Affiliation(s)
- Kun Yao
- Brain Science Basic Laboratory, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi, 214151, Jiangsu, China.,Department of Clinical Psychology, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi, 214151, Jiangsu, China
| | - Hua Liu
- Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, Jiangsu, China
| | - Jiajun Yin
- Brain Science Basic Laboratory, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi, 214151, Jiangsu, China
| | - Jianmin Yuan
- Brain Science Basic Laboratory, The Affiliated Wuxi Mental Health Center with Nanjing Medical University, Wuxi, 214151, Jiangsu, China.
| | - Hong Tao
- Department of Pharmacy, The Second Affiliated Hospital of Soochow University, Suzhou, 215004, Jiangsu, China.
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13
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Sun G, Dong Y, Sun C, Yao H, Lin Z. Vital Role of Glutamate Dehydrogenase Gene in Ammonia Detoxification and the Association Between its SNPs and Ammonia Tolerance in Sinonovacula constricta. Front Physiol 2021; 12:664804. [PMID: 34025453 PMCID: PMC8131826 DOI: 10.3389/fphys.2021.664804] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 03/22/2021] [Indexed: 11/17/2022] Open
Abstract
Increasing evidence has revealed accumulated ammonia will cause adverse effects on the growth, reproduction, and survival of aquatic animals. As a marine benthic mollusk, the razor clam Sinonovacula constricta shows better growth and survival under high ammonia nitrogen environment. However, little is known about its adaptation mechanisms to high ammonia stress in an integrated mariculture system. In this study, we analyzed the association between the polymorphism of glutamate dehydrogenase gene (GDH), a key gene involved in ammonia nitrogen detoxification, and ammonia tolerance. The results showed that 26 and 22 single-nucleotide polymorphisms (SNPs) of GDH in S. constricta (denoted as Sc-GDH) were identified from two geographical populations, respectively. Among them, two SNPs (c.323T > C and c.620C > T) exhibited a significant and strong association with ammonia tolerance, suggesting that Sc-GDH gene could serve as a potential genetic marker for molecular marker–assisted selection to increase survival rate and production of S. constricta. To observe the histological morphology and explore the histocellular localization of Sc-GDH, by paraffin section and hematoxylin–eosin staining, the gills were divided into gill filament (contains columnar and flattened cells) and gill cilia, whereas hepatopancreas was made up of individual hepatocytes. The results of immunohistochemistry indicated that the columnar cells of gill filaments and the endothelial cells of hepatocytes were the major sites for Sc-GDH secretion. Under ammonia stress (180 mg/L), the expression levels of Sc-GDH were extremely significantly downregulated at 24, 48, 72, and 96 h (P < 0.01) after RNA interference. Thus, we can speculate that Sc-GDH gene may play an important role in the defense process against ammonia stress. Overall, these findings laid a foundation for further research on the adaptive mechanisms to ammonia–nitrogen tolerance for S. constricta.
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Affiliation(s)
- Gaigai Sun
- College of Fisheries, Henan Normal University, Xinxiang, China
| | - Yinghui Dong
- Ninghai Institute of Mariculture Breeding and Seed Industry, Zhejiang Wanli University, Ninghai, China.,Key Laboratory of Aquatic Germplasm Resources of Zhejiang, College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, China
| | - Changsen Sun
- Ninghai Institute of Mariculture Breeding and Seed Industry, Zhejiang Wanli University, Ninghai, China
| | - Hanhan Yao
- Key Laboratory of Aquatic Germplasm Resources of Zhejiang, College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, China
| | - Zhihua Lin
- Ninghai Institute of Mariculture Breeding and Seed Industry, Zhejiang Wanli University, Ninghai, China.,Key Laboratory of Aquatic Germplasm Resources of Zhejiang, College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, China
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14
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Gonzalez-Riano C, Tapia-González S, Perea G, González-Arias C, DeFelipe J, Barbas C. Metabolic Changes in Brain Slices over Time: a Multiplatform Metabolomics Approach. Mol Neurobiol 2021; 58:3224-3237. [PMID: 33651263 DOI: 10.1007/s12035-020-02264-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 12/15/2020] [Indexed: 01/01/2023]
Abstract
Brain slice preparations are widely used for research in neuroscience. However, a high-quality preparation is essential and there is no consensus regarding stable parameters that can be used to define the status of the brain slice preparation after its collection at different time points. Thus, it is critical to fully characterize the experimental conditions for ex vivo studies using brain slices for electrophysiological recording. In this study, we used a multiplatform (LC-MS and GC-MS) untargeted metabolomics-based approach to shed light on the metabolome and lipidome changes taking place at different time intervals during the brain slice preparation process. We have found significant modifications in the levels of 300 compounds, including several lipid classes and their derivatives, as well as metabolites involved in the GABAergic pathway and the TCA cycle. All these preparation-dependent changes in the brain biochemistry related to the time interval should be taken into consideration for future studies to facilitate non-biased interpretations of the experimental results.
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Affiliation(s)
- Carolina Gonzalez-Riano
- Centro de Metabolómica y Bioanálisis (CEMBIO), Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, 28660, Boadilla del Monte, Spain
| | - Silvia Tapia-González
- Laboratorio Cajal de Circuitos Corticales (CTB), Universidad Politécnica de Madrid, Madrid, Spain
- Instituto Cajal (CSIC), Avenida Doctor Arce 37, 28002, Madrid, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), ISCIII, Madrid, Spain
| | - Gertrudis Perea
- Instituto Cajal (CSIC), Avenida Doctor Arce 37, 28002, Madrid, Spain
| | | | - Javier DeFelipe
- Laboratorio Cajal de Circuitos Corticales (CTB), Universidad Politécnica de Madrid, Madrid, Spain
- Instituto Cajal (CSIC), Avenida Doctor Arce 37, 28002, Madrid, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), ISCIII, Madrid, Spain
| | - Coral Barbas
- Centro de Metabolómica y Bioanálisis (CEMBIO), Facultad de Farmacia, Universidad San Pablo-CEU, CEU Universities, Urbanización Montepríncipe, 28660, Boadilla del Monte, Spain.
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15
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Iranmanesh Y, Jiang B, Favour OC, Dou Z, Wu J, Li J, Sun C. Mitochondria's Role in the Maintenance of Cancer Stem Cells in Glioblastoma. Front Oncol 2021; 11:582694. [PMID: 33692947 PMCID: PMC7937970 DOI: 10.3389/fonc.2021.582694] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/08/2021] [Indexed: 12/14/2022] Open
Abstract
Glioblastoma (GBM), one of the deadliest primary brain malignancies, is characterized by a high recurrence rate due to its limited response to existing therapeutic strategies such as chemotherapy, radiation therapy, and surgery. Several mechanisms and pathways have been identified to be responsible for GBM therapeutic resistance. Glioblastoma stem cells (GSCs) are known culprits of GBM resistance to therapy. GSCs are characterized by their unique self-renewal, differentiating capacity, and proliferative potential. They form a heterogeneous population of cancer stem cells within the tumor and are further divided into different subpopulations. Their distinct molecular, genetic, dynamic, and metabolic features distinguish them from neural stem cells (NSCs) and differentiated GBM cells. Novel therapeutic strategies targeting GSCs could effectively reduce the tumor-initiating potential, hence, a thorough understanding of mechanisms involved in maintaining GSCs' stemness cannot be overemphasized. The mitochondrion, a regulator of cellular physiological processes such as autophagy, cellular respiration, reactive oxygen species (ROS) generation, apoptosis, DNA repair, and cell cycle control, has been implicated in various malignancies (for instance, breast, lung, and prostate cancer). Besides, the role of mitochondria in GBM has been extensively studied. For example, when stressors, such as irradiation and hypoxia are present, GSCs utilize specific cytoprotective mechanisms like the activation of mitochondrial stress pathways to survive the harsh environment. Proliferating GBM cells exhibit increased cytoplasmic glycolysis in comparison to terminally differentiated GBM cells and quiescent GSCs that rely more on oxidative phosphorylation (OXPHOS). Furthermore, the Warburg effect, which is characterized by increased tumor cell glycolysis and decreased mitochondrial metabolism in the presence of oxygen, has been observed in GBM. Herein, we highlight the importance of mitochondria in the maintenance of GSCs.
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Affiliation(s)
| | - Biao Jiang
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University Medical School, Hangzhou, China
| | - Okoye C Favour
- School of Medicine, Zhejiang University, Hangzhou, China
| | - Zhangqi Dou
- Department of Neurosurgery, The 2nd Affiliated Hospital of Zhejiang University Medical School, Hangzhou, China
| | - Jiawei Wu
- Department of Neurosurgery, The 2nd Affiliated Hospital of Zhejiang University Medical School, Hangzhou, China
| | - Jinfan Li
- Department of Pathology, The 2nd Affiliated Hospital of Zhejiang University Medical School, Hangzhou, China
| | - Chongran Sun
- Department of Neurosurgery, The 2nd Affiliated Hospital of Zhejiang University Medical School, Hangzhou, China
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16
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Rice SA, Ten Have GAM, Reisz JA, Gehrke S, Stefanoni D, Frare C, Barati Z, Coker RH, D'Alessandro A, Deutz NEP, Drew KL. Nitrogen recycling buffers against ammonia toxicity from skeletal muscle breakdown in hibernating arctic ground squirrels. Nat Metab 2020; 2:1459-1471. [PMID: 33288952 PMCID: PMC7744440 DOI: 10.1038/s42255-020-00312-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 10/15/2020] [Indexed: 02/06/2023]
Abstract
Hibernation is a state of extraordinary metabolic plasticity. The pathways of amino acid metabolism as they relate to nitrogen homeostasis in hibernating mammals in vivo are unknown. Here we show, using pulse isotopic tracing, evidence of increased myofibrillar (skeletal muscle) protein breakdown and suppressed whole-body production of metabolites in vivo throughout deep torpor. As whole-body production of metabolites is suppressed, amino acids with nitrogenous side chains accumulate during torpor, while urea cycle intermediates do not. Using 15N stable isotope methodology in arctic ground squirrels (Urocitellus parryii), we provide evidence that free nitrogen is buffered and recycled into essential amino acids, non-essential amino acids and the gamma-glutamyl system during the inter-bout arousal period of hibernation. In the absence of nutrient intake or physical activity, our data illustrate the orchestration of metabolic pathways that sustain the provision of essential and non-essential amino acids and prevent ammonia toxicity during hibernation.
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Affiliation(s)
- Sarah A Rice
- Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, AK, USA
- Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Gabriella A M Ten Have
- Center for Translational Research in Aging and Longevity, Department of Health and Kinesiology, Texas A&M University, College Station, TX, USA
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Sarah Gehrke
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Davide Stefanoni
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Carla Frare
- Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, AK, USA
- Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Zeinab Barati
- Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Robert H Coker
- Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Nicolaas E P Deutz
- Center for Translational Research in Aging and Longevity, Department of Health and Kinesiology, Texas A&M University, College Station, TX, USA
| | - Kelly L Drew
- Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, AK, USA.
- Institute of Arctic Biology, Center for Transformative Research in Metabolism, University of Alaska Fairbanks, Fairbanks, AK, USA.
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17
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Functional validation of a human GLUD2 variant in a murine model of Parkinson's disease. Cell Death Dis 2020; 11:897. [PMID: 33093440 PMCID: PMC7582183 DOI: 10.1038/s41419-020-03043-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/17/2020] [Accepted: 09/21/2020] [Indexed: 02/06/2023]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disease characterized by Lewy body formation and progressive dopaminergic neuron death in the substantia nigra (SN). Genetic susceptibility is a strong risk factor for PD. Previously, a rare gain-of-function variant of GLUD2 glutamate dehydrogenase (T1492G) was reported to be associated with early onset in male PD patients; however, the function and underlying mechanism of this variant remains elusive. In the present study, we generated adeno-associated virus expressing GLUD2 and its mutant under the control of the glial fibrillary acidic protein promotor and injected the virus into the SN pars compacta of either untreated mice or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD model mice. Our results demonstrate that GLUD2 mutation in MPTP-induced PD mice exacerbates movement deficits and nigral dopaminergic neuron death and reduces glutamate transporters expression and function. Using GC-Q-TOF/MS-based metabolomics, we determined that GLUD2 mutation damages mitochondrial function by decreasing succinate dehydrogenase activity to impede the tricarboxylic acid cycle in the SN of MPTP-induced PD mice. Accordingly, GLUD2 mutant mice had reduced energy metabolism and increased apoptosis, possibly due to downregulation of brain-derived neurotrophic factor/nuclear factor E2-related factor 2 signaling in in vitro and in vivo PD models. Collectively, our findings verify the function of GLUD2 in PD and unravel a mechanism by which a genetic variant in human GLUD2 may contribute to disease onset.
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18
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Zhang J, Xie J, Gan Y, Coulter JA, Dawuda MM, Yu J, Lv J, Li J, Zhang X, Tang C, Wang C, Niu T, Calderón-Urrea A. Promoting pepper (Capsicum annuum) photosynthesis via chloroplast ultrastructure and enzyme activities by optimising the ammonium to nitrate ratio. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 47:303-317. [PMID: 32122461 DOI: 10.1071/fp19149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 11/16/2019] [Indexed: 05/26/2023]
Abstract
Optimal plant growth in many species is achieved when the two major forms of N are supplied at a particular ratio. In this pot experiment, the effects of five different ammonium:nitrate ratios (ANRs) (0:100, 12.5:87.5, 25:75, 37.5:62.5, and 50:50) on photosynthesis efficiency in chilli pepper (Capsicum annuum L.) plants were evaluated. The results showed that an ANR of 25:75 increased the contents of chl a, leaf area and dry matter, whereas chl b content was not affected by the ANRs. Regarding chlorophyll fluorescence, an ANR of 25:75 also enhanced the actual photochemical efficiency, photochemical quenching and maximum photosynthetic rate. However, the 0:100 and 50:50 ANRs resulted in higher values for nonphotochemical quenching. An inhibition of maximal photochemical efficiency was found when 50% NH4+ was supplied at the later stage of plant growth. The addition of 25% or 37.5% NH4+ was beneficial for gas exchange parameters and the 25% NH4+ optimised the thylakoid of chloroplasts. Compared with nitrate alone, 12.5–50% NH4+ upregulated glutamate dehydrogenase (GDH), the large subunit and the small subunit of Rubisco. It can be concluded that the 25:75 ANR accelerated N assimilation through active GDH, which provides a material basis for chloroplast and Rubisco formation, resulting in the increased photosynthetic rate and enhanced growth in chilli pepper.
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Affiliation(s)
- Jing Zhang
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Jianming Xie
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China; and Corresponding Author.
| | - Yantai Gan
- Agriculture and Agri-Food Canada, Swift Current Research and Development Centre, Swift Current, SK, S9H 3X2, Canada
| | - Jeffrey A Coulter
- Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA
| | - Mohammed Mujitaba Dawuda
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China; and Department of Horticulture, Faculty of Agriculture, University for Development Studies, Post Office Box TL 1882, Tamale, Ghana
| | - Jihua Yu
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Jian Lv
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Jing Li
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Xiaodan Zhang
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Chaonan Tang
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Cheng Wang
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Tianhang Niu
- College of Horticulture, Gansu Agricultural University, Yingmen Village, Anning District, Lanzhou, 730070, P.R. China
| | - Alejandro Calderón-Urrea
- College of Plant Protection, Gansu Agricultural University, Lanzhou 730070, P.R. China; and Department of Biology, College of Science and Mathematics, California State University, Fresno, Fresno, CA, USA
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19
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Pan L, Han P, Ma S, Peng R, Wang C, Kong W, Cong L, Fu J, Zhang Z, Yu H, Wang Y, Jiang J. Abnormal metabolism of gut microbiota reveals the possible molecular mechanism of nephropathy induced by hyperuricemia. Acta Pharm Sin B 2020; 10:249-261. [PMID: 32082971 PMCID: PMC7016297 DOI: 10.1016/j.apsb.2019.10.007] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 10/05/2019] [Accepted: 10/08/2019] [Indexed: 12/12/2022] Open
Abstract
The progression of hyperuricemia disease is often accompanied by damage to renal function. However, there are few studies on hyperuricemia nephropathy, especially its association with intestinal flora. This study combines metabolomics and gut microbiota diversity analysis to explore metabolic changes using a rat model as well as the changes in intestinal flora composition. The results showed that amino acid metabolism was disturbed with serine, glutamate and glutamine being downregulated whilst glycine, hydroxyproline and alanine being upregulated. The combined glycine, serine and glutamate could predict hyperuricemia nephropathy with an area under the curve of 1.00. Imbalanced intestinal flora was also observed. Flavobacterium, Myroides, Corynebacterium, Alcaligenaceae, Oligella and other conditional pathogens increased significantly in the model group, while Blautia and Roseburia, the short-chain fatty acid producing bacteria, declined greatly. At phylum, family and genus levels, disordered nitrogen circulation in gut microbiota was detected. In the model group, the uric acid decomposition pathway was enhanced with reinforced urea liver-intestine circulation. The results implied that the intestinal flora play a vital role in the pathogenesis of hyperuricemia nephropathy. Hence, modulation of gut microbiota or targeting at metabolic enzymes, i.e., urease, could assist the treatment and prevention of this disease.
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Affiliation(s)
- Libin Pan
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Pei Han
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Shurong Ma
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Ran Peng
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Can Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Weijia Kong
- Insitute of Medicinal Biotechnology, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Lin Cong
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Jie Fu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Zhengwei Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Hang Yu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
| | - Yan Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
- Corresponding authors. Tel.: +86 10 63165238, Fax: +86 10 63165238; Tel.: +86 10 83160005, Fax: +86 10 63017757.
| | - Jiandong Jiang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences/Peking Union Medical College, Beijing 100050, China
- Corresponding authors. Tel.: +86 10 63165238, Fax: +86 10 63165238; Tel.: +86 10 83160005, Fax: +86 10 63017757.
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Petraki Z, Droubogiannis S, Mylonaki K, Chlouverakis G, Plaitakis A, Spanaki C. Transgenic expression of the positive selected human GLUD2 gene improves in vivo glucose homeostasis by regulating basic insulin secretion. Metabolism 2019; 100:153958. [PMID: 31400387 DOI: 10.1016/j.metabol.2019.153958] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 07/24/2019] [Accepted: 08/04/2019] [Indexed: 12/19/2022]
Abstract
Glutamate dehydrogenase 1 (GDH1) contributes to glucose-stimulated insulin secretion in murine β-cells, but not to basic insulin release. The implications of these findings for human biology are unclear as humans have two GDH-specific enzymes: hGDH1 (GLUD1-encoded) and hGDH2 (GLUD2-encoded), a novel enzyme that is highly activated by ADP and L-leucine. Here we studied in vivo glucose homeostasis in transgenic (Tg) mice generated by inserting the GLUD2 gene and its putative regulatory elements into their genome. Using specific antibodies, we observed that hGDH2 was co-expressed with the endogenous murine GDH1 in pancreatic β-cells of Tg mice. Fasting blood glucose (FBG) levels were lower and of a narrower range in Tg (95% CI: 90.6-96.8 mg/dl; N = 26) than in Wt mice (95% CI: 136.2-151.4 mg/dl; N = 23; p < 0.0001), closely resembling those of healthy humans. GLUD2 also protected the host mouse from developing diabetes with advancing age. Tg animals maintained 2.6-fold higher fasting serum insulin levels (mean ± SD: 1.63 ± 0.15 ng/ml; N = 12) than Wt mice (0.63 ± 0.05 ng/ml; N = 12; p < 0.0001). Glucose loading (1 mg/g, given i.p.) induced comparable serum insulin increases in Tg and Wt mice, suggesting no significant GLUD2 effect on glucose-stimulated insulin release. L-leucine (0.25 mg/g given orally) induced a 2-fold increase in the serum insulin of the Wt mice, implying significant activation of the endogenous GDH1. However, L-leucine had little effect on the high insulin levels of the Tg mice, suggesting that, under the high ADP levels that prevail in β-cells in the fasting state, glutamate flux through hGDH2 is close to maximal. Hence, the present data, showing that GLUD2 expression in Tg mice improves in vivo glucose homeostasis by boosting fasting serum insulin levels, suggest that evolutionary adaptation of hGDH2 has enabled humans to achieve narrow-range euglycemia by regulating glutamate-mediated basal insulin secretion.
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Affiliation(s)
- Zoe Petraki
- Department of Neurology, School of Medicine, University of Crete, Voutes Place, 71500 Heraklion, Crete, Greece
| | - Stavros Droubogiannis
- Department of Neurology, School of Medicine, University of Crete, Voutes Place, 71500 Heraklion, Crete, Greece
| | - Konstantina Mylonaki
- Department of Neurology, School of Medicine, University of Crete, Voutes Place, 71500 Heraklion, Crete, Greece
| | - Gregory Chlouverakis
- Department of Social Medicine, Biostatistics Lab, School of Medicine, University of Crete, Voutes Place, 71500 Heraklion, Crete, Greece
| | - Andreas Plaitakis
- Department of Neurology, School of Medicine, University of Crete, Voutes Place, 71500 Heraklion, Crete, Greece
| | - Cleanthe Spanaki
- Department of Neurology, School of Medicine, University of Crete, Voutes Place, 71500 Heraklion, Crete, Greece.
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21
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Medrano E, Merselis DG, Bellantuono AJ, Rodriguez-Lanetty M. Proteomic Basis of Symbiosis: A Heterologous Partner Fails to Duplicate Homologous Colonization in a Novel Cnidarian- Symbiodiniaceae Mutualism. Front Microbiol 2019; 10:1153. [PMID: 31214134 PMCID: PMC6554683 DOI: 10.3389/fmicb.2019.01153] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 05/06/2019] [Indexed: 12/29/2022] Open
Abstract
Reef corals and sea anemones form symbioses with unicellular symbiotic dinoflagellates. The molecular circumventions that underlie the successful intracellular colonization of hosts by symbionts are still largely unknown. We conducted proteomic analyses to determine molecular differences of Exaiptasia pallida anemones colonized by physiologically different symbiont species, in comparison with symbiont-free (aposymbiotic) anemones. We compared one homologous species, Symbiodinium linucheae, that is natively associated with the clonal Exaiptasia strain (CC7) to another heterologous species, Durusdinium trenchii, a thermally tolerant species that colonizes numerous coral species. This approach allowed the discovery of a core set of host genes that are differentially regulated as a function of symbiosis regardless of symbiont species. The findings revealed that symbiont colonization at higher densities requires circumvention of the host cellular immunological response, enhancement of ammonium regulation, and suppression of phagocytosis after a host cell in colonized. Furthermore, the heterologous symbionts failed to duplicate the same level of homologous colonization within the host, evidenced by substantially lower symbiont densities. This reduced colonization of D. trenchii correlated with its inability to circumvent key host systems including autophagy-suppressing modulators, cytoskeletal alteration, and isomerase activity. The larger capability of host molecular circumvention by homologous symbionts could be the result of a longer evolutionary history of host/symbiont interactions, which translates into a more finely tuned symbiosis. These findings are of great importance within the context of the response of reef corals to climate change since it has been suggested that coral may acclimatize to ocean warming by changing their dominant symbiont species.
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Experimental evidence that maleic acid markedly compromises glutamate oxidation through inhibition of glutamate dehydrogenase and α-ketoglutarate dehydrogenase activities in kidney of developing rats. Mol Cell Biochem 2019; 458:99-112. [DOI: 10.1007/s11010-019-03534-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 04/10/2019] [Indexed: 12/12/2022]
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Chakraborty P, Chatterjee S, Kesarwani P, Thyagarajan K, Iamsawat S, Dalheim A, Nguyen H, Selvam SP, Nasarre P, Scurti G, Hardiman G, Maulik N, Ball L, Gangaraju V, Rubinstein MP, Klauber-DeMore N, Hill EG, Ogretmen B, Yu XZ, Nishimura MI, Mehrotra S. Thioredoxin-1 improves the immunometabolic phenotype of antitumor T cells. J Biol Chem 2019; 294:9198-9212. [PMID: 30971427 DOI: 10.1074/jbc.ra118.006753] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 03/25/2019] [Indexed: 12/16/2022] Open
Abstract
Adoptive transfer of tumor epitope-reactive T cells has emerged as a promising strategy to control tumor growth. However, chronically-stimulated T cells expanded for adoptive cell transfer are susceptible to cell death in an oxidative tumor microenvironment. Because oxidation of cell-surface thiols also alters protein functionality, we hypothesized that increasing the levels of thioredoxin (Trx), an antioxidant molecule facilitating reduction of proteins through cysteine thiol-disulfide exchange, in T cells will promote their sustained antitumor function. Using pre-melanosome protein (Pmel)-Trx1 transgenic mouse-derived splenic T cells, flow cytometry, and gene expression analysis, we observed here that higher Trx expression inversely correlated with reactive oxygen species and susceptibility to T-cell receptor restimulation or oxidation-mediated cell death. These Trx1-overexpressing T cells exhibited a cluster of differentiation 62Lhi (CD62Lhi) central memory-like phenotype with reduced glucose uptake (2-NBDGlo) and decreased effector function (interferon γlo). Furthermore, culturing tumor-reactive T cells in the presence of recombinant Trx increased the dependence of T cells on mitochondrial metabolism and improved tumor control. We conclude that strategies for increasing the antioxidant capacity of antitumor T cells modulate their immunometabolic phenotype leading to improved immunotherapeutic control of established tumors.
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Affiliation(s)
| | | | | | | | | | - Annika Dalheim
- the Department of Surgery, Loyola University, Maywood, Illinois 60153, and
| | | | | | | | - Gina Scurti
- the Department of Surgery, Loyola University, Maywood, Illinois 60153, and
| | | | - Nilanjana Maulik
- the Department of Surgery, University of Connecticut Health Center, Farmington, Connecticut 06030
| | | | | | | | | | - Elizabeth G Hill
- Public Health, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina 29425
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He S, Zhang X, Qu S. Glutamate, Glutamate Transporters, and Circadian Rhythm Sleep Disorders in Neurodegenerative Diseases. ACS Chem Neurosci 2019; 10:175-181. [PMID: 30485059 DOI: 10.1021/acschemneuro.8b00419] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Glutamate, a primary excitatory neurotransmitter and an important intermediate in the cellular metabolism of the brain, has a widespread influence in the sleep-wake regulatory system. Glutamate transporters, including vesicular glutamate transporters and excitatory amino acid transporters, serve as the main force controlling the extracellular concentration of glutamate in the brain. These are likely to be critical tools needed for the brain to modulate the sleep-wake cycle and are likely innervated by the circadian rhythm system in a day-night variant pattern. Because in the initial stages, nearly all patients with neurodegenerative diseases have rhythmic sleep disorders that become aggravated with disease development and often exhibit glutamate uptake dysfunction, we examined whether the above glutamate transporters could be used as potential targets to help address circadian rhythm sleep disorders in patients with neurodegenerative diseases. Therefore, in this review, we sought to analyze the principles governing glutamate transmission and discuss whether the circadian rhythm regulatory properties of these processes endow glutamate transporters with unique functions in the sleep-wake shift of the brain. We attempt to provide a theoretical framework in this field for future studies, to help in the exploration of potential therapeutic targets to delay or prevent the development of neurodegenerative diseases.
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Affiliation(s)
- Suifen He
- Central Laboratory, Shunde Hospital of Southern Medical University (The First People’s Hospital of Shunde Foshan), Foshan, Guangdong 528300, China
- Department of Neurology, Shunde Hospital of Southern Medical University (The First People’s Hospital of Shunde Foshan), Foshan, Guangdong 528300, China
- Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Xiuping Zhang
- Teaching Center of Experimental Medicine, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Shaogang Qu
- Central Laboratory, Shunde Hospital of Southern Medical University (The First People’s Hospital of Shunde Foshan), Foshan, Guangdong 528300, China
- Department of Neurology, Shunde Hospital of Southern Medical University (The First People’s Hospital of Shunde Foshan), Foshan, Guangdong 528300, China
- Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, Guangdong 510515, China
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Wu L, Zhang X, Tang Z, Li Y, Li T, Xu Q, Zhen J, Huang F, Yang J, Chen C, Wu Z, Li M, Sun J, Chen J, An R, Zhao S, Jiang Q, Zhu W, Yin Y, Sun Z. Low-Protein Diets Decrease Porcine Nitrogen Excretion but with Restrictive Effects on Amino Acid Utilization. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:8262-8271. [PMID: 29984998 DOI: 10.1021/acs.jafc.8b03299] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Reducing dietary crude protein (CP) intake effectively decreases nitrogen excretion in growing-finishing pigs but at the expense of poor growth when dietary CP content is reduced by ≥3%. In this study, we investigated the main disadvantages of low-protein diets supplemented with lysine, methionine, threonine, and tryptophan in pigs. First, changes in the nitrogen balance in response to differences in dietary CP content (18%, 15%, and 13.5%) were investigated in barrows (40 kg). Then, barrows (40 kg) surgically fitted with catheters in the mesenteric vein, portal vein, hepatic vein, and carotid artery were used to investigate changes in amino acid (AA) metabolism in the portal-drained viscera and liver in response to differences in dietary CP content. The results showed that low-protein diets reduced fecal and urinary nitrogen excretion ( P < 0.05) meanwhile resulted in significant decreases in nitrogen retention ( P < 0.05). Moreover, a reduction in the dietary CP content from 18% to 13.5% resulted in decreases in the net portal fluxes of NH3, glycine, and alanine as well as in the urea production in the liver ( P < 0.05), whereas their values as a percentage of nitrogen intake did not decline ( P > 0.05). The net portal fluxes of nonessential AA (NEAA) were reduced in the low-protein diet groups ( P < 0.05), while essential AA consumption in the liver increased ( P < 0.05). Thus, low-protein diets result in reductions in both nitrogen excretion and retention, and NEAA deficiency may be a major disadvantage of low-protein diets.
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Affiliation(s)
- Liuting Wu
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Xiangxin Zhang
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Zhiru Tang
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Yunxia Li
- Institute of Animal Nutrition , Sichuan Agricultural University , Chengdu 611130 , P. R. China
| | - Tiejun Li
- Institute of Subtropical Agriculture , The Chinese Academy of Sciences , Changsha 410125 , P. R. China
| | - Qingqing Xu
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Jifu Zhen
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Feiruo Huang
- College of Animal Science and Technology , Huazhong Agricultural University , Wuhan 430070 , P. R. China
| | - Jing Yang
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Cheng Chen
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Zhaoliang Wu
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Mao Li
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Jiajing Sun
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Jinchao Chen
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Rui An
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
| | - Shengjun Zhao
- School of Animal Science and Nutritional Engineering , Wuhan Polytechnic University , Wuhan 430023 , P. R. China
| | - Qingyan Jiang
- College of Animal Science and Technology , Huanan Agricultural University , Guangzhou 510642 , P. R. China
| | - Weiyun Zhu
- College of Animal Science and Technology , Nanjing Agricultural University , Nanjing 210095 , P. R. China
| | - Yulong Yin
- Institute of Subtropical Agriculture , The Chinese Academy of Sciences , Changsha 410125 , P. R. China
| | - Zhihong Sun
- Laboratory for Bio-feed and Molecular Nutrition, College of Animal Science and Technology , Southwest University , Chongqing 400715 , P. R. China
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26
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Mansilla WD, Silva KE, Zhu C, Nyachoti CM, Htoo JK, Cant JP, de Lange CFM. Ammonia-Nitrogen Added to Low-Crude-Protein Diets Deficient in Dispensable Amino Acid-Nitrogen Increases the Net Release of Alanine, Citrulline, and Glutamate Post-Splanchnic Organ Metabolism in Growing Pigs. J Nutr 2018; 148:1081-1087. [PMID: 29878142 DOI: 10.1093/jn/nxy076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/20/2018] [Indexed: 01/27/2023] Open
Abstract
Background Dietary ammonia is rapidly absorbed but poorly used for urea synthesis in pigs fed low-crude-protein (low-CP) diets deficient in dispensable amino acid (DAA)-nitrogen. Objective We explored the effect of dietary ammonia on net amino acid (AA) balances in portal-drained viscera (PDV) and livers of pigs fed a diet deficient in DAA-nitrogen. Methods Eight barrows with an initial body weight (BW) of 26.5 ± 1.4 kg (mean + SD) were surgically fitted with 4 catheters each (portal, hepatic, and mesenteric veins and carotid artery). The pigs were restricted-fed (2.8 × 191 kcal/kg BW0.60) for 7 d, and every 8 h a diet deficient in DAA-nitrogen supplemented with increasing amounts of ammonia-nitrogen (CP = 7.76%, 9.27%, and 10.77% for the control and low- and high-ammonia diets, respectively). The treatment sequence was based on a 3 × 3 Latin-square design with 3 consecutive periods. On the last day of each period, blood flows in portal and hepatic veins were determined with a continuous infusion of ρ-amino hippuric acid into the mesenteric vein. Consecutive blood samples were taken for AA concentration in blood plasma, and AA balances were calculated for PDV and the liver. Results Cumulative release of citrulline (Cit) and proline (Pro) increased with ammonia supplementation in PDV but decreased for glutamine (Gln) and glycine (Gly) (Gln: -19.32 ± 3.56, -32.50 ± 3.73, and -42.11 ± 3.55 mmol/meal for the control and low- and high-ammonia groups, respectively; P ≤ 0.05). Cumulative release of alanine (Ala), glutamic acid (Glu), and Gln increased with ammonia supplementation across the liver (P ≤ 0.05). When combined, PDV+liver, the cumulative release of Ala, Cit, and Glu increased with ammonia-nitrogen supplementation (P ≤ 0.05). Conclusion Dietary ammonia could be used as a nitrogen supplement to increase the synthesis of Ala, Cit, and Glu across splanchnic organs in pigs fed a diet deficient in DAA-nitrogen.
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Affiliation(s)
- Wilfredo D Mansilla
- Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada
| | - Kayla E Silva
- Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada
| | - Cuilan Zhu
- Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada
| | - Charles M Nyachoti
- Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | - John K Htoo
- Evonik Nutrition and Care GmbH, Hanau-Wolfgang, Germany
| | - John P Cant
- Department of Animal Biosciences, University of Guelph, Guelph, Ontario, Canada
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Mathioudakis L, Bourbouli M, Daklada E, Kargatzi S, Michaelidou K, Zaganas I. Localization of Human Glutamate Dehydrogenases Provides Insights into Their Metabolic Role and Their Involvement in Disease Processes. Neurochem Res 2018; 44:170-187. [PMID: 29943084 DOI: 10.1007/s11064-018-2575-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 06/11/2018] [Accepted: 06/13/2018] [Indexed: 12/21/2022]
Abstract
Glutamate dehydrogenase (GDH) catalyzes the reversible deamination of L-glutamate to α-ketoglutarate and ammonia. In mammals, GDH contributes to important processes such as amino acid and carbohydrate metabolism, energy production, ammonia management, neurotransmitter recycling and insulin secretion. In humans, two isoforms of GDH are found, namely hGDH1 and hGDH2, with the former being ubiquitously expressed and the latter found mainly in brain, testis and kidney. These two iso-enzymes display highly divergent allosteric properties, especially concerning their basal activity, ADP activation and GTP inhibition. On the other hand, both enzymes are thought to predominantly localize in the mitochondrial matrix, even though alternative localizations have been proposed. To further study the subcellular localization of the two human iso-enzymes, we created HEK293 cell lines stably over-expressing hGDH1 and hGDH2. In these cell lines, immunofluorescence and enzymatic analyses verified the overexpression of both hGDH1 and hGDH2 iso-enzymes, whereas subcellular fractionation followed by immunoblotting showed their predominantly mitochondrial localization. Given that previous studies have only indirectly compared the subcellular localization of the two iso-enzymes, we co-expressed them tagged with different fluorescent dyes (green and red fluorescent protein for hGDH1 and hGDH2, respectively) and found them to co-localize. Despite the wealth of information related to the functional properties of hGDH1 and hGDH2 and the availability of the hGDH1 structure, there is still an ongoing debate concerning their metabolic role and their involvement in disease processes. Data on the localization of hGDHs, as the ones presented here, could contribute to better understanding of the function of these important human enzymes.
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Affiliation(s)
- Lambros Mathioudakis
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Mara Bourbouli
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Elisavet Daklada
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Sofia Kargatzi
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Kleita Michaelidou
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece
| | - Ioannis Zaganas
- Neurology Laboratory, Medical School, University of Crete, Heraklion, Crete, Greece. .,Department of Neurology, University Hospital of Heraklion, Heraklion, Crete, Greece.
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28
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Andersson LE, Shcherbina L, Al-Majdoub M, Vishnu N, Arroyo CB, Aste Carrara J, Wollheim CB, Fex M, Mulder H, Wierup N, Spégel P. Glutamine-Elicited Secretion of Glucagon-Like Peptide 1 Is Governed by an Activated Glutamate Dehydrogenase. Diabetes 2018; 67:372-384. [PMID: 29229616 DOI: 10.2337/db16-1441] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 12/07/2017] [Indexed: 11/13/2022]
Abstract
Glucagon-like peptide 1 (GLP-1), secreted from intestinal L cells, glucose dependently stimulates insulin secretion from β-cells. This glucose dependence prevents hypoglycemia, rendering GLP-1 analogs a useful and safe treatment modality in type 2 diabetes. Although the amino acid glutamine is a potent elicitor of GLP-1 secretion, the responsible mechanism remains unclear. We investigated how GLP-1 secretion is metabolically coupled in L cells (GLUTag) and in vivo in mice using the insulin-secreting cell line INS-1 832/13 as reference. A membrane-permeable glutamate analog (dimethylglutamate [DMG]), acting downstream of electrogenic transporters, elicited similar alterations in metabolism as glutamine in both cell lines. Both DMG and glutamine alone elicited GLP-1 secretion in GLUTag cells and in vivo, whereas activation of glutamate dehydrogenase (GDH) was required to stimulate insulin secretion from INS-1 832/13 cells. Pharmacological inhibition in vivo of GDH blocked secretion of GLP-1 in response to DMG. In conclusion, our results suggest that nonelectrogenic nutrient uptake and metabolism play an important role in L cell stimulus-secretion coupling. Metabolism of glutamine and related analogs by GDH in the L cell may explain why GLP-1 secretion, but not that of insulin, is activated by these secretagogues in vivo.
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Affiliation(s)
- Lotta E Andersson
- Unit of Molecular Metabolism, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Liliya Shcherbina
- Neuroendocrine Cell Biology, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Mahmoud Al-Majdoub
- Unit of Molecular Metabolism, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Neelanjan Vishnu
- Unit of Molecular Metabolism, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | | | - Jonathan Aste Carrara
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Lund, Sweden
| | - Claes B Wollheim
- Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
- Department of Cell Physiology and Metabolism, University Medical Centre, Geneva, Switzerland
| | - Malin Fex
- Unit of Molecular Metabolism, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Hindrik Mulder
- Unit of Molecular Metabolism, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Nils Wierup
- Neuroendocrine Cell Biology, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
| | - Peter Spégel
- Unit of Molecular Metabolism, Department of Clinical Sciences, Lund University Diabetes Centre, Clinical Research Centre, Skåne University Hospital, Malmö, Sweden
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Lund, Sweden
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29
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Grimaldi M, Karaca M, Latini L, Brioudes E, Schalch T, Maechler P. Identification of the molecular dysfunction caused by glutamate dehydrogenase S445L mutation responsible for hyperinsulinism/hyperammonemia. Hum Mol Genet 2018; 26:3453-3465. [PMID: 28911206 DOI: 10.1093/hmg/ddx213] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/01/2017] [Indexed: 01/14/2023] Open
Abstract
Congenital hyperinsulinism/hyperammonemia (HI/HA) syndrome gives rise to unregulated protein-induced insulin secretion from pancreatic beta-cells, fasting hypoglycemia and elevated plasma ammonia levels. Mutations associated with HI/HA were identified in the Glud1 gene, encoding for glutamate dehydrogenase (GDH). We aimed at identifying the molecular causes of dysregulation in insulin secretion and ammonia production conferred by the most frequent HI/HA mutation Ser445Leu. Following transduction with adenoviruses carrying the human GDH-wild type or GDH-S445L-mutant gene, immunoblotting showed efficient expression of the transgenes in all the investigated cell types. Enzymatic activity tested in INS-1E beta-cells revealed that the mutant was much more sensitive to the allosteric activator ADP, rendering it highly responsive to substrates. INS-1E cells expressing either the wild type or mutant GDH responded similarly to glucose stimulation regarding mitochondrial activation and insulin secretion. However, at basal glucose glutamine stimulation increased mitochondrial activity and insulin release only in the mutant cells. In mouse and human islets, expression of mutant GDH resulted in robust elevation of insulin secretion upon glutamine stimulation, not observed in control islets. Hepatocytes expressing either the wild type or mutant GDH produced similar levels of ammonia when exposed to glutamine, although alanine response was strongly elevated with the mutant form. In conclusion, the GDH-S445L mutation confers hyperactivity to this enzyme due to higher sensitivity to ADP allosteric activation. This renders beta-cells responsive to amino acid stimulation, explaining protein-induced hypoglycemia secondary to non-physiological insulin release. Hepatocytes carrying mutant GDH produced more ammonia upon alanine exposure, which underscores hyperammonemia developed by the patients.
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Affiliation(s)
- Mariagrazia Grimaldi
- Department of Cell Physiology and Metabolism.,Faculty Diabetes Center, University of Geneva Medical Center, 1206 Geneva, Switzerland
| | - Melis Karaca
- Department of Cell Physiology and Metabolism.,Faculty Diabetes Center, University of Geneva Medical Center, 1206 Geneva, Switzerland
| | - Livia Latini
- Department of Cell Physiology and Metabolism.,Faculty Diabetes Center, University of Geneva Medical Center, 1206 Geneva, Switzerland
| | - Estelle Brioudes
- Faculty Diabetes Center, University of Geneva Medical Center, 1206 Geneva, Switzerland.,Department of Surgery, Cell Isolation and Transplantation Center, Geneva University Hospital, Geneva, Switzerland
| | - Thomas Schalch
- Department of Molecular Biology, Faculty of Science, Institute of Genetics and Genomics of Geneva (iGE3), Sciences III, University of Geneva, 1211 Geneva 4, Switzerland
| | - Pierre Maechler
- Department of Cell Physiology and Metabolism.,Faculty Diabetes Center, University of Geneva Medical Center, 1206 Geneva, Switzerland
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Distribution of the branched-chain α-ketoacid dehydrogenase complex E1α subunit and glutamate dehydrogenase in the human brain and their role in neuro-metabolism. Neurochem Int 2018; 112:49-58. [DOI: 10.1016/j.neuint.2017.10.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 10/18/2017] [Accepted: 10/18/2017] [Indexed: 11/17/2022]
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Wang T, Yao W, He Q, Shao Y, Zheng R, Huang F. L-leucine stimulates glutamate dehydrogenase activity and glutamate synthesis by regulating mTORC1/SIRT4 pathway in pig liver. ACTA ACUST UNITED AC 2017; 4:329-337. [PMID: 30175263 PMCID: PMC6116330 DOI: 10.1016/j.aninu.2017.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 12/15/2017] [Indexed: 01/09/2023]
Abstract
The liver is the most essential organ for the metabolism of ammonia, in where most of ammonia is removed by urea and glutamine synthesis. Regulated by leucine, glutamate dehydrogenase (GDH) catalyzes the reversible inter-conversion of glutamate to ammonia. To determine the mechanism of leucine regulating GDH, pigs weighing 20 ± 1 kg were infused for 80 min with ammonium chloride or alanine in the presence or absence of leucine. Primary pig hepatocytes were incubated with or without leucine. In the in vivo experiments with either ammonium or alanine as the nitrogen source, addition of leucine significantly inhibited ureagenesis and promoted the production of glutamate and glutamine in the perfused pig liver (P < 0.05). Similarly, leucine stimulated GDH activity and inhibited sirtuin4 (SIRT4) gene expression (P < 0.01). Leucine could also activate mammalian target of rapamycin complex 1 (mTORC1) signaling (P < 0.05), as evidenced by the increased phosphorylation levels of ribosomal protein S6 kinase 1 (S6K1) and ribosomal protein S6 (S6). Interestingly, the leucine-induced mTORC1 pathway activation suitably correlated with increased GDH activity and decreased expression of SIRT4. Similar results were observed in primary cultured hepatocytes. Notably, leucine exerted no significant change in GDH activity in SIRT4-deficient hepatocytes (P > 0.05), while mTORC1 signaling was activated. Leucine exerted no significant changes in both GDH activity and SIRT4 gene expression in rapamycin treated hepatocytes (P > 0.05). In conclusion, L-leucine increases GDH activity and stimulates glutamate synthesis from different nitrogen sources by regulating mTORC1/SIRT4 pathway in the liver of pigs.
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Affiliation(s)
- Tongxin Wang
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Weilei Yao
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Qiongyu He
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Yafei Shao
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Ruilong Zheng
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Feiruo Huang
- Department of Animal Nutrition and Feed Science, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
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Waitkus MS, Pirozzi CJ, Moure CJ, Diplas BH, Hansen LJ, Carpenter AB, Yang R, Wang Z, Ingram BO, Karoly ED, Mohney RP, Spasojevic I, McLendon RE, Friedman HS, He Y, Bigner DD, Yan H. Adaptive Evolution of the GDH2 Allosteric Domain Promotes Gliomagenesis by Resolving IDH1 R132H-Induced Metabolic Liabilities. Cancer Res 2017; 78:36-50. [PMID: 29097607 DOI: 10.1158/0008-5472.can-17-1352] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 09/25/2017] [Accepted: 10/27/2017] [Indexed: 01/13/2023]
Abstract
Hotspot mutations in the isocitrate dehydrogenase 1 (IDH1) gene occur in a number of human cancers and confer a neomorphic enzyme activity that catalyzes the conversion of α-ketoglutarate (αKG) to the oncometabolite D-(2)-hydroxyglutarate (D2HG). In malignant gliomas, IDH1R132H expression induces widespread metabolic reprogramming, possibly requiring compensatory mechanisms to sustain the normal biosynthetic requirements of actively proliferating tumor cells. We used genetically engineered mouse models of glioma and quantitative metabolomics to investigate IDH1R132H-dependent metabolic reprogramming and its potential to induce biosynthetic liabilities that can be exploited for glioma therapy. In gliomagenic neural progenitor cells, IDH1R132H expression increased the abundance of dipeptide metabolites, depleted key tricarboxylic acid cycle metabolites, and slowed progression of murine gliomas. Notably, expression of glutamate dehydrogenase GDH2, a hominoid-specific enzyme with relatively restricted expression to the brain, was critically involved in compensating for IDH1R132H-induced metabolic alterations and promoting IDH1R132H glioma growth. Indeed, we found that recently evolved amino acid substitutions in the GDH2 allosteric domain conferred its nonredundant, glioma-promoting properties in the presence of IDH1 mutation. Our results indicate that among the unique roles for GDH2 in the human forebrain is its ability to limit IDH1R132H-mediated metabolic liabilities, thus promoting glioma growth in this context. Results from this study raise the possibility that GDH2-specific inhibition may be a viable therapeutic strategy for gliomas with IDH mutations.Significance: These findings show that the homonid-specific brain enzyme GDH2 may be essential to mitigate metabolic liabilities created by IDH1 mutations in glioma, with possible implications to leverage its therapeutic management by IDH1 inhibitors. Cancer Res; 78(1); 36-50. ©2017 AACR.
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Affiliation(s)
- Matthew S Waitkus
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Christopher J Pirozzi
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Casey J Moure
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Bill H Diplas
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Landon J Hansen
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Austin B Carpenter
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Rui Yang
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Zhaohui Wang
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | | | | | | | - Ivan Spasojevic
- Department of Medicine - Oncology, Duke University School of Medicine, Durham, North Carolina.,Pharmacokinetics/Pharmacodynamics Core Laboratory, Duke Cancer Institute, Durham, North Carolina
| | - Roger E McLendon
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Henry S Friedman
- Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina.,Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina
| | - Yiping He
- Department of Pathology, Duke University, Durham, North Carolina.,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
| | - Darell D Bigner
- Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina.,Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina
| | - Hai Yan
- Department of Pathology, Duke University, Durham, North Carolina. .,Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, North Carolina
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Vázquez-Martínez O, Méndez I, Turrubiate I, Valente-Godínez H, Pérez-Mendoza M, García-Tejada P, Díaz-Muñoz M. Restricted feeding modulates the daily variations of liver glutamate dehydrogenase activity, expression, and histological location. Exp Biol Med (Maywood) 2017; 242:945-952. [PMID: 28440738 PMCID: PMC5407590 DOI: 10.1177/1535370217699533] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 02/11/2017] [Indexed: 02/05/2023] Open
Abstract
Glutamate dehydrogenase is an important enzyme in the hepatic regulation of nitrogen and energy metabolism. It catalyzes one of the most relevant anaplerotic reactions. Although its relevance in liver homeostasis has been widely described, its daily pattern and responsiveness to restricted feeding protocols has not been studied. We explored the daily variations of liver glutamate dehydrogenase transcription, protein, activity, and histochemical and subcellular location in a protocol of daytime food synchronization in rats. Restricted feeding involved food access for 2 h each day for three weeks. Control groups included food ad libitum as well as acute fasting (21 h fasting) and refeeding (22 h fasting followed by 2 h of food access). Glutamate dehydrogenase mRNA, protein, activity, and histological location were measured every 3 h by qPCR, Western blot, spectrophotometry, and immunohistochemistry, respectively, to generate 24-h profiles. Restricted feeding promoted higher levels of mitochondrial glutamate dehydrogenase protein and activity, as well as a loss of 24-h rhythmicity, in comparison to ad libitum conditions. The rhythmicity of glutamate dehydrogenase activity detected in serum was changed. The data demonstrated that daytime restricted feeding enhanced glutamate dehydrogenase protein and activity levels in liver mitochondria, changed the rhythmicity of its mRNA and serum activity, but without effect in its expression in hepatocytes surrounding central and portal veins. These results could be related to the adaptation in nitrogen and energy metabolism that occurs in the liver during restricted feeding and the concomitant expression of the food entrainable oscillator. Impact statement For the first time, we are reporting the changes in daily rhythmicity of glutamate dehydrogenase (GDH) mRNA, protein and activity that occur in the liver during the expression of the food entrained oscillator (FEO). These results are part of the metabolic adaptations that modulate the hepatic timing system when the protocol of daytime restricted feeding is applied. As highlight, it was demonstrated higher GDH protein and activity in the mitochondrial fraction. These results contribute to a better understanding of the influence of the FEO in the energy and nitrogen handling in the liver. They could also be significant in the pathophysiology of hepatic diseases related with circadian abnormalities.
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Affiliation(s)
- Olivia Vázquez-Martínez
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Querétaro 76230, QRO, México
| | - Isabel Méndez
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Querétaro 76230, QRO, México
| | - Isaías Turrubiate
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Querétaro 76230, QRO, México
| | - Héctor Valente-Godínez
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Querétaro 76230, QRO, México
| | - Moisés Pérez-Mendoza
- Facultad de Ciencias, Unidad Multidisciplinaria de Docencia e Investigación, Campus UNAM-Juriquilla, Querétaro 76230, QRO, México
| | - Paola García-Tejada
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Querétaro 76230, QRO, México
| | - Mauricio Díaz-Muñoz
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Querétaro 76230, QRO, México
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The Glutamate Dehydrogenase Pathway and Its Roles in Cell and Tissue Biology in Health and Disease. BIOLOGY 2017; 6:biology6010011. [PMID: 28208702 PMCID: PMC5372004 DOI: 10.3390/biology6010011] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/10/2017] [Accepted: 01/16/2017] [Indexed: 02/07/2023]
Abstract
Glutamate dehydrogenase (GDH) is a hexameric enzyme that catalyzes the reversible conversion of glutamate to α-ketoglutarate and ammonia while reducing NAD(P)⁺ to NAD(P)H. It is found in all living organisms serving both catabolic and anabolic reactions. In mammalian tissues, oxidative deamination of glutamate via GDH generates α-ketoglutarate, which is metabolized by the Krebs cycle, leading to the synthesis of ATP. In addition, the GDH pathway is linked to diverse cellular processes, including ammonia metabolism, acid-base equilibrium, redox homeostasis (via formation of fumarate), lipid biosynthesis (via oxidative generation of citrate), and lactate production. While most mammals possess a single GDH1 protein (hGDH1 in the human) that is highly expressed in the liver, humans and other primates have acquired, via duplication, an hGDH2 isoenzyme with distinct functional properties and tissue expression profile. The novel hGDH2 underwent rapid evolutionary adaptation, acquiring unique properties that enable enhanced enzyme function under conditions inhibitory to its ancestor hGDH1. These are thought to provide a biological advantage to humans with hGDH2 evolution occurring concomitantly with human brain development. hGDH2 is co-expressed with hGDH1 in human brain, kidney, testis and steroidogenic organs, but not in the liver. In human cerebral cortex, hGDH1 and hGDH2 are expressed in astrocytes, the cells responsible for removing and metabolizing transmitter glutamate, and for supplying neurons with glutamine and lactate. In human testis, hGDH2 (but not hGDH1) is densely expressed in the Sertoli cells, known to provide the spermatids with lactate and other nutrients. In steroid producing cells, hGDH1/2 is thought to generate reducing equivalents (NADPH) in the mitochondria for the biosynthesis of steroidal hormones. Lastly, up-regulation of hGDH1/2 expression occurs in cancer, permitting neoplastic cells to utilize glutamine/glutamate for their growth. In addition, deregulation of hGDH1/2 is implicated in the pathogenesis of several human disorders.
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35
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Amino Acid Catabolism in Alzheimer's Disease Brain: Friend or Foe? OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:5472792. [PMID: 28261376 PMCID: PMC5316456 DOI: 10.1155/2017/5472792] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 12/04/2016] [Accepted: 01/04/2017] [Indexed: 01/08/2023]
Abstract
There is a dire need to discover new targets for Alzheimer's disease (AD) drug development. Decreased neuronal glucose metabolism that occurs in AD brain could play a central role in disease progression. Little is known about the compensatory neuronal changes that occur to attempt to maintain energy homeostasis. In this review using the PubMed literature database, we summarize evidence that amino acid oxidation can temporarily compensate for the decreased glucose metabolism, but eventually altered amino acid and amino acid catabolite levels likely lead to toxicities contributing to AD progression. Because amino acids are involved in so many cellular metabolic and signaling pathways, the effects of altered amino acid metabolism in AD brain are far-reaching. Possible pathological results from changes in the levels of several important amino acids are discussed. Urea cycle function may be induced in endothelial cells of AD patient brains, possibly to remove excess ammonia produced from increased amino acid catabolism. Studying AD from a metabolic perspective provides new insights into AD pathogenesis and may lead to the discovery of dietary metabolite supplements that can partially compensate for alterations of enzymatic function to delay AD or alleviate some of the suffering caused by the disease.
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36
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Campos JM, Neves LX, de Paiva NCN, de Oliveira E Castro RA, Casé AH, Carneiro CM, Andrade MHG, Castro-Borges W. Understanding global changes of the liver proteome during murine schistosomiasis using a label-free shotgun approach. J Proteomics 2017; 151:193-203. [PMID: 27427331 DOI: 10.1016/j.jprot.2016.07.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 07/03/2016] [Accepted: 07/11/2016] [Indexed: 12/21/2022]
Abstract
Schistosomiasis is an endemic disease affecting over 207 million people worldwide caused by helminth parasites of the genus Schistosoma. In Brazil the disease is responsible for the loss of up to 800 lives annually, resulting from the desabilitating effects of this chronic condition. In this study, we infected Balb/c mice with Schistosoma mansoni and analysed global changes in the proteomic profile of soluble liver proteins. Our shotgun analyses revealed predominance of up-regulation of proteins at 5weeks of infection, coinciding with the onset of egg laying, and a remarkable down-regulation of liver constituents at 7weeks, when severe tissue damage is installed. Representatives of glycolytic enzymes and stress response (in particular at the endoplasmic reticulum) were among the most differentially expressed molecules found in the infected liver. Collectively, our data contribute over 70 molecules not previously reported to be found at altered levels in murine schistosomiasis to further exploration of their potential as biomarkers of the disease. Moreover, understanding their intricate interaction using bioinformatics approach can potentially bring clarity to unknown mechanisms linked to the establishment of this condition in the vertebrate host. SIGNIFICANCE To our knowledge, this study refers to the first shotgun proteomic analysis to provide an inventory of the global changes in the liver soluble proteome caused by Schistosoma mansoni in the Balb/c model. It also innovates by yielding data on quantification of the identified molecules as a manner to clarify and give insights into the underlying mechanisms for establishment of Schistosomiasis, a neglected tropical disease with historical prevalence in Brazil.
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Affiliation(s)
- Jonatan Marques Campos
- Programa de Pós Graduação em Bioengenharia, Universidade Federal de São João del Rei, São João del Rei, MG, Brazil; Programa de Pós Graduação em Biotecnologia, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Leandro Xavier Neves
- Programa de Pós Graduação em Biotecnologia, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | | | | | - Ana Helena Casé
- Programa de Pós Graduação em Biotecnologia, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Cláudia Martins Carneiro
- Departamento de Análises Clínicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - Milton Hércules Guerra Andrade
- Departamento de Ciências Biológicas, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil
| | - William Castro-Borges
- Departamento de Ciências Biológicas, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil.
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Nissen JD, Lykke K, Bryk J, Stridh MH, Zaganas I, Skytt DM, Schousboe A, Bak LK, Enard W, Pääbo S, Waagepetersen HS. Expression of the human isoform of glutamate dehydrogenase, hGDH2, augments TCA cycle capacity and oxidative metabolism of glutamate during glucose deprivation in astrocytes. Glia 2016; 65:474-488. [PMID: 28032919 DOI: 10.1002/glia.23105] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 11/23/2016] [Accepted: 11/30/2016] [Indexed: 01/06/2023]
Abstract
A key enzyme in brain glutamate homeostasis is glutamate dehydrogenase (GDH) which links carbohydrate and amino acid metabolism mediating glutamate degradation to CO2 and expanding tricarboxylic acid (TCA) cycle capacity with intermediates, i.e. anaplerosis. Humans express two GDH isoforms, GDH1 and 2, whereas most other mammals express only GDH1. hGDH1 is widely expressed in human brain while hGDH2 is confined to astrocytes. The two isoforms display different enzymatic properties and the nature of these supports that hGDH2 expression in astrocytes potentially increases glutamate oxidation and supports the TCA cycle during energy-demanding processes such as high intensity glutamatergic signaling. However, little is known about how expression of hGDH2 affects the handling of glutamate and TCA cycle metabolism in astrocytes. Therefore, we cultured astrocytes from cerebral cortical tissue of hGDH2-expressing transgenic mice. We measured glutamate uptake and metabolism using [3 H]glutamate, while the effect on metabolic pathways of glutamate and glucose was evaluated by use of 13 C and 14 C substrates and analysis by mass spectrometry and determination of radioactively labeled metabolites including CO2 , respectively. We conclude that hGDH2 expression increases capacity for uptake and oxidative metabolism of glutamate, particularly during increased workload and aglycemia. Additionally, hGDH2 expression increased utilization of branched-chain amino acids (BCAA) during aglycemia and caused a general decrease in oxidative glucose metabolism. We speculate, that expression of hGDH2 allows astrocytes to spare glucose and utilize BCAAs during substrate shortages. These findings support the proposed role of hGDH2 in astrocytes as an important fail-safe during situations of intense glutamatergic activity. GLIA 2017;65:474-488.
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Affiliation(s)
- Jakob D Nissen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Kasper Lykke
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Jaroslaw Bryk
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, 02109, Germany
| | - Malin H Stridh
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Ioannis Zaganas
- Neurology Laboratory, School of Health Sciences, Faculty of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Dorte M Skytt
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Arne Schousboe
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Lasse K Bak
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
| | - Wolfgang Enard
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, 02109, Germany
| | - Svante Pääbo
- Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, 02109, Germany
| | - Helle S Waagepetersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen, 2100, Denmark
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Glutamate dehydrogenase activator BCH stimulating reductive amination prevents high fat/high fructose diet-induced steatohepatitis and hyperglycemia in C57BL/6J mice. Sci Rep 2016; 5:37468. [PMID: 27874078 PMCID: PMC5118703 DOI: 10.1038/srep37468] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 10/28/2016] [Indexed: 12/19/2022] Open
Abstract
Individuals with non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2D) induced by high calorie western diet are characterized by enhanced lipogenesis and gluconeogenesis in the liver. Stimulation of reductive amination may shift tricarboxylic acid cycle metabolism for lipogenesis and gluconeogenesis toward glutamate synthesis with increase of NAD+/NADH ratio and thus, ameliorate high calorie diet-induced fatty liver and hyperglycemia. Stimulation of reductive amination through glutamate dehydrogenase (GDH) activator 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH) reduced both de novo lipogenesis and gluconeogenesis but increased the activities of sirtuins and AMP-activated kinase in primary hepatocytes. Long-term BCH treatment improved most metabolic alterations induced by high fat/high fructose (HF/HFr) diet in C57BL/6J mice. BCH prevented HF/HFr-induced fat accumulation and activation of stress/inflammation signals such as phospho-JNK, phospho-PERK, phospho-p38, and phospho-NFκB in liver tissues. Furthermore, BCH treatment reduced the expression levels of inflammatory cytokines such as TNF-α and IL-1β in HF/HFr-fed mouse liver. BCH also reduced liver collagen and plasma levels of alanine transaminase and aspartate transaminase. On the other hand, BCH significantly improved fasting hyperglycemia and glucose tolerance in HF/HFr-fed mice. In conclusion, stimulation of reductive amination through GDH activation can be used as a strategy to prevent high calorie western diet-induced NAFLD and T2D.
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Liver BCATm transgenic mouse model reveals the important role of the liver in maintaining BCAA homeostasis. J Nutr Biochem 2016; 40:132-140. [PMID: 27886623 DOI: 10.1016/j.jnutbio.2016.10.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 10/19/2016] [Accepted: 10/25/2016] [Indexed: 01/08/2023]
Abstract
Unlike other amino acids, the branched-chain amino acids (BCAAs) largely bypass first-pass liver degradation due to a lack of hepatocyte expression of the mitochondrial branched-chain aminotransferase (BCATm). This sets up interorgan shuttling of BCAAs and liver-skeletal muscle cooperation in BCAA catabolism. To explore whether complete liver catabolism of BCAAs may impact BCAA shuttling in peripheral tissues, the BCATm gene was stably introduced into mouse liver. Two transgenic mouse lines with low and high hepatocyte expression of the BCATm transgene (LivTg-LE and LivTg-HE) were created and used to measure liver and plasma amino acid concentrations and determine whether the first two BCAA enzymatic steps in liver, skeletal muscle, heart and kidney were impacted. Expression of the hepatic BCATm transgene lowered the concentrations of hepatic BCAAs while enhancing the concentrations of some nonessential amino acids. Extrahepatic BCAA metabolic enzymes and plasma amino acids were largely unaffected, and no growth rate or body composition differences were observed in the transgenic animals as compared to wild-type mice. Feeding the transgenic animals a high-fat diet did not reverse the effect of the BCATm transgene on the hepatic BCAA catabolism, nor did the high-fat diet cause elevation in plasma BCAAs. However, the high-fat-diet-fed BCATm transgenic animals experienced attenuation in the mammalian target of rapamycin (mTOR) pathway in the liver and had impaired blood glucose tolerance. These results suggest that complete liver BCAA metabolism influences the regulation of glucose utilization during diet-induced obesity.
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Spanaki C, Kotzamani D, Plaitakis A. Widening Spectrum of Cellular and Subcellular Expression of Human GLUD1 and GLUD2 Glutamate Dehydrogenases Suggests Novel Functions. Neurochem Res 2016; 42:92-107. [PMID: 27422263 DOI: 10.1007/s11064-016-1986-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/20/2016] [Accepted: 06/22/2016] [Indexed: 12/11/2022]
Abstract
Mammalian glutamate dehydrogenase1 (GDH1) (E.C. 1.4.1.3) is a mitochondrial enzyme that catalyzes the reversible oxidative deamination of glutamate to α-ketoglutarate and ammonia while reducing NAD+ and/or NADP+ to NADH and/or NADPH. It links amino acid with carbohydrate metabolism, contributing to Krebs cycle anaplerosis, energy production, ammonia handling and redox homeostasis. Although GDH1 was one of the first major metabolic enzymes to be studied decades ago, its role in cell biology is still incompletely understood. There is however growing interest in a novel GDH2 isoenzyme that emerged via duplication in primates and underwent rapid evolutionary selection concomitant with prefrontal human cortex expansion. Also, the anaplerotic function of GDH1 and GDH2 is currently under sharp focus as this relates to the biology of glial tumors and other neoplasias. Here we used antibodies specific for human GDH1 (hGDH1) and human GDH2 (hGDH2) to study the expression of these isoenzymes in human tissues. Results revealed that both hGDH1 and hGDH2 are expressed in human brain, kidney, testis and steroidogenic organs. However, distinct hGDH1 and hGDH2 expression patterns emerged. Thus, while the Sertoli cells of human testis were strongly positive for hGDH2, they were negative for hGDH1. Conversely, hGDH1 showed very high levels of expression in human liver, but hepatocytes were virtually devoid of hGDH2. In human adrenals, both hGDHs were densely expressed in steroid-producing cells, with hGDH2 expression pattern matching that of the cholesterol side chain cleavage system involved in steroid synthesis. Similarly in human ovaries and placenta, both hGDH1 and hGDH2 were densely expressed in estrogen producing cells. In addition, hGDH1, being a housekeeping enzyme, was also expressed in cells that lack endocrine function. Regarding human brain, study of cortical sections using immunofluorescence (IF) with confocal microscopy revealed that hGDH1 and hGDH2 were both expressed in the cytoplasm of gray and white matter astrocytes within coarse structures resembling mitochondria. Additionally, hGDH1 localized to the nuclear membrane of a subpopulation of astrocytes and of the vast majority of oligodendrocytes and their precursors. Remarkably, hGDH2-specific staining was detected in human cortical neurons, with different expression patterns having emerged. One pattern, observed in large cortical neurons (some with pyramidal morphology), was a hGDH2-specific labeling of cytoplasmic structures resembling mitochondria. These were distributed either in the cell body-axon or on the cell surface in close proximity to astrocytic end-feet that encircle glutamatergic synapses. Another pattern was observed in small cortical neurons with round dense nuclei in which the hGDH2-specific staining was found in the nuclear membrane. A detailed description of these observations and their functional implications, suggesting that the GDH flux is used by different cells to serve some of their unique functions, is presented below.
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Affiliation(s)
- Cleanthe Spanaki
- Department of Neurology, Faculty of Medicine, School of Health Sciences, University of Crete, Heraklion, Crete, 71003, Greece
| | - Dimitra Kotzamani
- Department of Neurology, Faculty of Medicine, School of Health Sciences, University of Crete, Heraklion, Crete, 71003, Greece
| | - Andreas Plaitakis
- Department of Neurology, Faculty of Medicine, School of Health Sciences, University of Crete, Heraklion, Crete, 71003, Greece. .,Icahn School of Medicine at Mount Sinai, OneGustave L. Levy Place, New York, 10029, USA.
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Golizeh M, Geib T, Sleno L. Identification of 4-hydroxynonenal protein targets in rat, mouse and human liver microsomes by two-dimensional liquid chromatography/tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:1488-1494. [PMID: 27321836 DOI: 10.1002/rcm.7577] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 03/30/2016] [Accepted: 04/01/2016] [Indexed: 06/06/2023]
Abstract
RATIONALE 4-Hydroxynonenal (HNE), endogenously generated through peroxidation and breakdown of polyunsaturated fatty acids, has been linked to a number of adverse biological effects through carbonylation of essential biomolecules. Covalent binding of HNE to proteins can alter their structure and functions, causing cell damage as well as adverse immune responses. The liver plays a predominant role in metabolic transformations and hepatic proteins are often targeted by reactive metabolites. METHODS Rat, mouse and human liver microsomes were incubated with HNE, enzymatically digested, and subjected to strong cation-exchange peptide fractionation prior to liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis coupled to electrospray ionization quadrupole time-of-flight (QqTOF) mass spectrometry. HNE-modified peptides were detected by probability-driven peptide spectral matching and comparative analysis between treated and control samples, and confirmed based on accurate mass and high-resolution MS/MS spectra. RESULTS A total of 99, 123 and 51 HNE-modified peptides were identified in rat, mouse and human liver microsomes related to 76, 103 and 44 target proteins, respectively. Eight proteins were found to be adducted by HNE in all three species, including ATP synthase, carbamoyl phosphate synthase, cytochrome P450 1A2, glutamate dehydrogenase 1, protein ERGIC-53, protein disulfide-isomerase, and voltage-dependent anion-selective channel protein 1. These proteins play crucial roles in cellular processes and their covalent modification could potentially alter their function and lead to cytotoxicity. CONCLUSIONS An analytical approach was developed for the identification of in vitro HNE protein targets in rat, mouse and human liver microsomes using two-dimensional (2D) LC/MS/MS. This approach can be applied to study HNE modification of proteins in vitro and in vivo, providing insight into the toxicology of HNE protein adduction. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Makan Golizeh
- Chemistry Department/Pharmaqam, Université du Québec à Montréal (UQÀM), Montréal, QC, Canada
| | - Timon Geib
- Chemistry Department/Pharmaqam, Université du Québec à Montréal (UQÀM), Montréal, QC, Canada
| | - Lekha Sleno
- Chemistry Department/Pharmaqam, Université du Québec à Montréal (UQÀM), Montréal, QC, Canada
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Import of a major mitochondrial enzyme depends on synergy between two distinct helices of its presequence. Biochem J 2016; 473:2813-29. [PMID: 27422783 PMCID: PMC5095901 DOI: 10.1042/bcj20160535] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 07/15/2016] [Indexed: 12/13/2022]
Abstract
Mammalian glutamate dehydrogenase (GDH), a nuclear-encoded enzyme central to cellular metabolism, is among the most abundant mitochondrial proteins (constituting up to 10% of matrix proteins). To attain such high levels, GDH depends on very efficient mitochondrial targeting that, for human isoenzymes hGDH1 and hGDH2, is mediated by an unusually long cleavable presequence (N53). Here, we studied the mitochondrial transport of these proteins using isolated yeast mitochondria and human cell lines. We found that both hGDHs were very rapidly imported and processed in isolated mitochondria, with their presequences (N53) alone being capable of directing non-mitochondrial proteins into mitochondria. These presequences were predicted to form two α helices (α1: N 1–10; α2: N 16–32) separated by loops. Selective deletion of the α1 helix abolished the mitochondrial import of hGDHs. While the α1 helix alone had a very weak hGDH mitochondrial import capacity, it could direct efficiently non-mitochondrial proteins into mitochondria. In contrast, the α2 helix had no autonomous mitochondrial-targeting capacity. A peptide consisting of α1 and α2 helices without intervening sequences had GDH transport efficiency comparable with that of N53. Mutagenesis of the cleavage site blocked the intra-mitochondrial processing of hGDHs, but did not affect their mitochondrial import. Replacement of all three positively charged N-terminal residues (Arg3, Lys7 and Arg13) by Ala abolished import. We conclude that the synergistic interaction of helices α1 and α2 is crucial for the highly efficient import of hGDHs into mitochondria.
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Ghallab A, Cellière G, Henkel SG, Driesch D, Hoehme S, Hofmann U, Zellmer S, Godoy P, Sachinidis A, Blaszkewicz M, Reif R, Marchan R, Kuepfer L, Häussinger D, Drasdo D, Gebhardt R, Hengstler JG. Model-guided identification of a therapeutic strategy to reduce hyperammonemia in liver diseases. J Hepatol 2016; 64:860-71. [PMID: 26639393 DOI: 10.1016/j.jhep.2015.11.018] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 11/15/2015] [Accepted: 11/16/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND & AIMS Recently, spatial-temporal/metabolic mathematical models have been established that allow the simulation of metabolic processes in tissues. We applied these models to decipher ammonia detoxification mechanisms in the liver. METHODS An integrated metabolic-spatial-temporal model was used to generate hypotheses of ammonia metabolism. Predicted mechanisms were validated using time-resolved analyses of nitrogen metabolism, activity analyses, immunostaining and gene expression after induction of liver damage in mice. Moreover, blood from the portal vein, liver vein and mixed venous blood was analyzed in a time dependent manner. RESULTS Modeling revealed an underestimation of ammonia consumption after liver damage when only the currently established mechanisms of ammonia detoxification were simulated. By iterative cycles of modeling and experiments, the reductive amidation of alpha-ketoglutarate (α-KG) via glutamate dehydrogenase (GDH) was identified as the lacking component. GDH is released from damaged hepatocytes into the blood where it consumes ammonia to generate glutamate, thereby providing systemic protection against hyperammonemia. This mechanism was exploited therapeutically in a mouse model of hyperammonemia by injecting GDH together with optimized doses of cofactors. Intravenous injection of GDH (720 U/kg), α-KG (280 mg/kg) and NADPH (180 mg/kg) reduced the elevated blood ammonia concentrations (>200 μM) to levels close to normal within only 15 min. CONCLUSION If successfully translated to patients the GDH-based therapy might provide a less aggressive therapeutic alternative for patients with severe hyperammonemia.
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Affiliation(s)
- Ahmed Ghallab
- Leibniz Research Centre for Working Environment and Human Factors at the Technical University Dortmund, Dortmund, Germany; Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt.
| | - Géraldine Cellière
- Sorbonne Universités, Inria, UPMC Univ Paris 06, Lab. J.L. Lions UMR CNRS 7598, Paris, France
| | | | | | - Stefan Hoehme
- Institute of Computer Science and Interdisciplinary Centre for Bioinformatics, University of Leipzig, Leipzig, Germany
| | - Ute Hofmann
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart and University of Tuebingen, Germany
| | - Sebastian Zellmer
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany
| | - Patricio Godoy
- Leibniz Research Centre for Working Environment and Human Factors at the Technical University Dortmund, Dortmund, Germany
| | - Agapios Sachinidis
- Institute of Neurophysiology and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
| | - Meinolf Blaszkewicz
- Leibniz Research Centre for Working Environment and Human Factors at the Technical University Dortmund, Dortmund, Germany
| | - Raymond Reif
- Leibniz Research Centre for Working Environment and Human Factors at the Technical University Dortmund, Dortmund, Germany
| | - Rosemarie Marchan
- Leibniz Research Centre for Working Environment and Human Factors at the Technical University Dortmund, Dortmund, Germany
| | - Lars Kuepfer
- Computational Systems Biology, Bayer Technology Services GmbH, Leverkusen, Germany
| | - Dieter Häussinger
- Clinic for Gastroenterology, Hepatology and Infectious Diseases, Heinrich-Heine-University, Düsseldorf, Germany
| | - Dirk Drasdo
- Sorbonne Universités, Inria, UPMC Univ Paris 06, Lab. J.L. Lions UMR CNRS 7598, Paris, France; Institute of Computer Science and Interdisciplinary Centre for Bioinformatics, University of Leipzig, Leipzig, Germany
| | - Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors at the Technical University Dortmund, Dortmund, Germany.
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Astroglial glutamate transporters coordinate excitatory signaling and brain energetics. Neurochem Int 2016; 98:56-71. [PMID: 27013346 DOI: 10.1016/j.neuint.2016.03.014] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/22/2022]
Abstract
In the mammalian brain, a family of sodium-dependent transporters maintains low extracellular glutamate and shapes excitatory signaling. The bulk of this activity is mediated by the astroglial glutamate transporters GLT-1 and GLAST (also called EAAT2 and EAAT1). In this review, we will discuss evidence that these transporters co-localize with, form physical (co-immunoprecipitable) interactions with, and functionally couple to various 'energy-generating' systems, including the Na(+)/K(+)-ATPase, the Na(+)/Ca(2+) exchanger, glycogen metabolizing enzymes, glycolytic enzymes, and mitochondria/mitochondrial proteins. This functional coupling is bi-directional with many of these systems both being regulated by glutamate transport and providing the 'fuel' to support glutamate uptake. Given the importance of glutamate uptake to maintaining synaptic signaling and preventing excitotoxicity, it should not be surprising that some of these systems appear to 'redundantly' support the energetic costs of glutamate uptake. Although the glutamate-glutamine cycle contributes to recycling of neurotransmitter pools of glutamate, this is an over-simplification. The ramifications of co-compartmentalization of glutamate transporters with mitochondria for glutamate metabolism are discussed. Energy consumption in the brain accounts for ∼20% of the basal metabolic rate and relies almost exclusively on glucose for the production of ATP. However, the brain does not possess substantial reserves of glucose or other fuels. To ensure adequate energetic supply, increases in neuronal activity are matched by increases in cerebral blood flow via a process known as 'neurovascular coupling'. While the mechanisms for this coupling are not completely resolved, it is generally agreed that astrocytes, with processes that extend to synapses and endfeet that surround blood vessels, mediate at least some of the signal that causes vasodilation. Several studies have shown that either genetic deletion or pharmacologic inhibition of glutamate transport impairs neurovascular coupling. Together these studies strongly suggest that glutamate transport not only coordinates excitatory signaling, but also plays a pivotal role in regulating brain energetics.
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Yu LJ, Wall BA, Wangari-Talbot J, Chen S. Metabotropic glutamate receptors in cancer. Neuropharmacology 2016; 115:193-202. [PMID: 26896755 DOI: 10.1016/j.neuropharm.2016.02.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 02/07/2016] [Accepted: 02/09/2016] [Indexed: 01/31/2023]
Abstract
Metabotropic glutamate receptors (mGluRs) are widely known for their roles in synaptic signaling. However, accumulating evidence suggests roles of mGluRs in human malignancies in addition to synaptic transmission. Somatic cell homeostasis presents intriguing possibilities of mGluRs and glutamate signaling as novel targets for human cancers. More recently, aberrant glutamate signaling has been shown to participate in the transformation and maintenance of various cancer types, including glioma, melanoma skin cancer, breast cancer, and prostate cancer, indicating that genes encoding mGluRs, GRMs, can function as oncogenes. Here, we provide a review on the interactions of mGluRs and their ligand, glutamate, in processes that promote the growth of tumors of neuronal and non-neuronal origins. Further, we discuss the evolution of riluzole, a glutamate release inhibitor approved for amyotrophic lateral sclerosis (ALS), but now fashioned as an mGluR1 inhibitor for melanoma therapy and as a radio-sensitizer for tumors that have metastasized to the brain. With the success of riluzole, it is not far-fetched to believe that other drugs that may act directly or indirectly on other mGluRs can be beneficial for multiple applications. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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Affiliation(s)
- Lumeng J Yu
- Susan Lehman Cullman Laboratory for Cancer Research, Ernest Mario School of Pharmacy, Rutgers University, NJ, USA
| | - Brian A Wall
- Susan Lehman Cullman Laboratory for Cancer Research, Ernest Mario School of Pharmacy, Rutgers University, NJ, USA; Global Product Safety, Colgate-Palmolive Company, Piscataway, NJ, USA
| | - Janet Wangari-Talbot
- Susan Lehman Cullman Laboratory for Cancer Research, Ernest Mario School of Pharmacy, Rutgers University, NJ, USA
| | - Suzie Chen
- Susan Lehman Cullman Laboratory for Cancer Research, Ernest Mario School of Pharmacy, Rutgers University, NJ, USA; The Cancer Institute of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08903, USA.
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Bera S, Lamba S, Rashid M, Sharma AK, Medvinsky AB, Acquisti C, Chakraborty A, Li BL. Robust regulation of hepatic pericentral amination by glutamate dehydrogenase kinetics. Integr Biol (Camb) 2016; 8:1126-1132. [DOI: 10.1039/c6ib00158k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
α-Ketoglutarate substrate inhibition kinetics of hepatic glutamate dehydrogenase amination activity confers robust control over the ratio between glutamate and ammonium.
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Affiliation(s)
- Soumen Bera
- School of Mathematics
- Statistics and Computational Sciences
- Central University of Rajasthan
- Ajmer
- India
| | - Sanjay Lamba
- School of Mathematics
- Statistics and Computational Sciences
- Central University of Rajasthan
- Ajmer
- India
| | - Mubasher Rashid
- School of Mathematics
- Statistics and Computational Sciences
- Central University of Rajasthan
- Ajmer
- India
| | - Anuj K. Sharma
- School of Chemical Sciences and Pharmacy
- Central University of Rajasthan
- Ajmer
- India
| | | | | | - Amit Chakraborty
- School of Mathematics
- Statistics and Computational Sciences
- Central University of Rajasthan
- Ajmer
- India
| | - Bai-Lian Li
- Ecological Complexity and Modeling Laboratory
- University of California
- Riverside
- USA
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Li L, Zhang P, Zheng P, Bao Z, Wang Y, Huang F. Hepatic cumulative net appearance of amino acids and related gene expression response to different protein diets in pigs. Livest Sci 2015. [DOI: 10.1016/j.livsci.2015.10.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Evolution of GLUD2 Glutamate Dehydrogenase Allows Expression in Human Cortical Neurons. Mol Neurobiol 2015; 53:5140-8. [PMID: 26399640 DOI: 10.1007/s12035-015-9429-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 09/07/2015] [Indexed: 10/23/2022]
Abstract
Human hGDH2 arose via duplication in the apes and driven by positive selection acquired enhanced catalytic ability under conditions inhibitory to its precursor hGDH1 (common to all mammals). To explore the biological advantage provided by the novel enzyme, we studied, by immunohistochemistry (IHC) and immunofluorescence (IF), hGDH1 and hGDH2 expression in the human brain. Studies on human cortical tissue using anti-hGDH1-specific antibody revealed that hGDH1 was expressed in glial cells (astrocytes, oligodendrocytes, and oligodendrocyte precursors) with neurons being devoid of hGDH1 staining. In contrast, an hGDH2-specific antiserum labeled both astrocytes and neurons. Specifically, hGDH2 immunoreactivity was found in the cytoplasm of large neuronal cells within coarse structures resembling mitochondria. These were distributed either in the perikaryon or in the cell periphery. Double immunofluorescence (IF) suggested that the latter represented hGDH2-labeled mitochondria of presynaptic nerve terminals. Hence, hGDH2 evolution bestowed large human neurons with enhanced glutamate metabolizing capacity, thus strengthening cortical excitatory transmission.
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Kelly PS, Breen L, Gallagher C, Kelly S, Henry M, Lao NT, Meleady P, O'Gorman D, Clynes M, Barron N. Re-programming CHO cell metabolism using miR-23 tips the balance towards a highly productive phenotype. Biotechnol J 2015; 10:1029-40. [DOI: 10.1002/biot.201500101] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/24/2015] [Accepted: 06/03/2015] [Indexed: 12/21/2022]
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50
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Bejarano E, Rodríguez-Navarro JA. Autophagy and amino acid metabolism in the brain: implications for epilepsy. Amino Acids 2014; 47:2113-26. [DOI: 10.1007/s00726-014-1822-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 07/31/2014] [Indexed: 12/31/2022]
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