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Diehl JJE, van Eerden E, Duijster M, Kwakkel RP. Supply organ development of young broilers in response to increased carbohydrates and amino acids in the starter period. Poult Sci 2024; 103:104092. [PMID: 39116662 PMCID: PMC11363853 DOI: 10.1016/j.psj.2024.104092] [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: 04/04/2024] [Revised: 06/27/2024] [Accepted: 07/08/2024] [Indexed: 08/10/2024] Open
Abstract
The growth of broiler chickens is marked by high fluctuations, varying nutrient requirement, early growth is characterized by high allometric growth rates of supply organs, which if underdeveloped, can impede nutrient efficiency and growth of demand organs like muscle and skeleton. This study aimed to investigate the impact of carbohydrate- and amino-acid-rich diets on the development of supply organs in broiler chickens. Four dietary treatments were used in a 2 × 2 factorial arrangement of treatments with apparent metabolizable energy (AME) at 2 levels (low: 2,750 kcal/kg and high: 3,050 kcal/kg) and standardized ileal digestible (SID) lysine at 2 levels (low: 1.0% and high: 1.2%) in the starter diets. Feed intake (FI) and BW gain were measured weekly; dissections were conducted at d 4 and d 11 to determine supply organ weights. Allometric growth of the liver was higher (P < 0.001) in the high AME and low lysine group compared to the other groups. For the pancreas, the highest (P < 0.001) allometric growth rate was in the high lysine groups. The small intestines responded differently; the duodenum had the highest (P < 0.001) allometric growth rate in the high AME groups and the jejunum in the low lysine groups, whereas the ileum showed an effect of diet density. For performance, high AME from carbohydrates, via maize starch, had a negative effect (P < 0.001) on FI and BW gain. High lysine had a positive effect (P < 0.001) on BW gain and FI, and high lysine alleviated part of the detrimental effect of high AME from carbohydrates. This effect was visible from d 0 to d 11, and persisted till the end of the trial on d 35. In conclusion, feeding a diet with a high AME from carbohydrates has negative consequences for the development of the supply organs of broilers.
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Affiliation(s)
- J J E Diehl
- Animal Nutrition Group, Department of Animal Sciences, Wageningen University, 6700AH Wageningen, The Netherlands.
| | - E van Eerden
- Schothorst Feed Research, 8200AM Lelystad, The Netherlands
| | - M Duijster
- Global Nutrition Department, De Heus Animal Nutrition B.V., 6710BJ Ede, The Netherlands
| | - R P Kwakkel
- Animal Nutrition Group, Department of Animal Sciences, Wageningen University, 6700AH Wageningen, The Netherlands
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2
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Njei B, Al-Ajlouni YA, Ameyaw P, Njei LP, Boateng S. Role of ammonia and glutamine in the pathogenesis and progression of metabolic dysfunction-associated steatotic liver disease: A systematic review. J Gastroenterol Hepatol 2024; 39:1788-1808. [PMID: 38763916 DOI: 10.1111/jgh.16603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 04/10/2024] [Accepted: 04/24/2024] [Indexed: 05/21/2024]
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD) affects over 30% of the global population, with a significant risk of advancing to liver cirrhosis and hepatocellular carcinoma. The roles of ammonia and glutamine in MASLD's pathogenesis are increasingly recognized, prompting this systematic review. This systematic review was conducted through a meticulous search of literature on December 21, 2023, across five major databases, focusing on studies that addressed the relationship between ammonia or glutamine and MASLD. The quality of the included studies was evaluated using CASP checklists. This study is officially registered in the PROSPERO database (CRD42023495619) and was conducted without external funding or sponsorship. Following PRISMA guidelines, 13 studies were included in this review. The studies were conducted globally, with varying sample sizes and study designs. The appraisal indicated a mainly low bias, confirming the reliability of the evidence. Glutamine's involvement in MASLD emerged as multifaceted, with its metabolic role being critical for liver function and disease progression. Variable expressions of glutamine synthetase and glutaminase enzymes highlight metabolic complexity whereas ammonia's impact through urea cycle dysfunction suggests avenues for therapeutic intervention. However, human clinical trials are lacking. This review emphasizes the necessity of glutamine and ammonia in understanding MASLD and identifies potential therapeutic targets. The current evidence, while robust, points to the need for human studies to corroborate preclinical findings. A personalized approach to treatment, informed by metabolic differences in MASLD patients, is advocated, alongside future large-scale clinical trials for a deeper exploration into these metabolic pathways.
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Affiliation(s)
- Basile Njei
- International Medicine Program, Section of Digestive Diseases, Yale University, New Haven, Connecticut, USA
| | | | - Prince Ameyaw
- Yale Affiliated Hospitals Program, Bridgeport, Connecticut, USA
| | - Lea-Pearl Njei
- University of Maryland Baltimore County, Baltimore, Maryland, USA
| | - Sarpong Boateng
- Yale Affiliated Hospitals Program, Bridgeport, Connecticut, USA
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3
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Tambay V, Raymond VA, Voisin L, Meloche S, Bilodeau M. Reprogramming of Glutamine Amino Acid Transporters Expression and Prognostic Significance in Hepatocellular Carcinoma. Int J Mol Sci 2024; 25:7558. [PMID: 39062801 PMCID: PMC11277143 DOI: 10.3390/ijms25147558] [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: 06/05/2024] [Revised: 07/05/2024] [Accepted: 07/07/2024] [Indexed: 07/28/2024] Open
Abstract
Hepatocellular carcinoma (HCC) is the most prevalent primary liver malignancy and is a major cause of cancer-related mortality in the world. This study aimed to characterize glutamine amino acid transporter expression profiles in HCC compared to those of normal liver cells. In vitro and in vivo models of HCC were studied using qPCR, whereas the prognostic significance of glutamine transporter expression levels within patient tumors was analyzed through RNAseq. Solute carrier (SLC) 1A5 and SLC38A2 were targeted through siRNA or gamma-p-nitroanilide (GPNA). HCC cells depended on exogenous glutamine for optimal survival and growth. Murine HCC cells showed superior glutamine uptake rate than normal hepatocytes (p < 0.0001). HCC manifested a global reprogramming of glutamine transporters compared to normal liver: SLC38A3 levels decreased, whereas SLC38A1, SLC7A6, and SLC1A5 levels increased. Also, decreased SLC6A14 and SLC38A3 levels or increased SLC38A1, SLC7A6, and SLC1A5 levels predicted worse survival outcomes (all p < 0.05). Knockdown of SLC1A5 and/or SLC38A2 expression in human Huh7 and Hep3B HCC cells, as well as GPNA-mediated inhibition, significantly decreased the uptake of glutamine; combined SLC1A5 and SLC38A2 targeting had the most considerable impact (all p < 0.05). This study revealed glutamine transporter reprogramming as a novel hallmark of HCC and that such expression profiles are clinically significant.
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Affiliation(s)
- Vincent Tambay
- Laboratoire d’Hépatologie cellulaire, Centre de Recherche du Centre Hospitalier de l’Université de Montréal, Montréal, QC H2X 0A9, Canada
| | - Valérie-Ann Raymond
- Laboratoire d’Hépatologie cellulaire, Centre de Recherche du Centre Hospitalier de l’Université de Montréal, Montréal, QC H2X 0A9, Canada
| | - Laure Voisin
- Institut de Recherche en Immunologie et en Cancérologie de l’Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Sylvain Meloche
- Institut de Recherche en Immunologie et en Cancérologie de l’Université de Montréal, Montréal, QC H3T 1J4, Canada
- Département de Pharmacologie et Physiologie, Université de Montréal, Montréal, QC H3C 3J7, Canada
| | - Marc Bilodeau
- Laboratoire d’Hépatologie cellulaire, Centre de Recherche du Centre Hospitalier de l’Université de Montréal, Montréal, QC H2X 0A9, Canada
- Département de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada
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Das D, Wang X, Chiu YC, Bouamar H, Sharkey FE, Lopera JE, Lai Z, Weintraub ST, Han X, Zou Y, Chen HIH, Zeballos Torrez CR, Gu X, Cserhati M, Michalek JE, Halff GA, Chen Y, Zheng S, Cigarroa FG, Sun LZ. Integrative multi-omics characterization of hepatocellular carcinoma in Hispanic patients. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.04.27.24306447. [PMID: 38746245 PMCID: PMC11092709 DOI: 10.1101/2024.04.27.24306447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Background The incidence and mortality rates of hepatocellular carcinoma (HCC) among Hispanics in the United States are much higher than those of non-Hispanic whites. We conducted comprehensive multi-omics analyses to understand molecular alterations in HCC among Hispanic patients. Methods Paired tumor and adjacent non-tumor samples were collected from 31 Hispanic HCC in South Texas (STX-Hispanic) for genomic, transcriptomic, proteomic, and metabolomic profiling. Additionally, serum lipids were profiled in 40 Hispanic and non-Hispanic patients with or without clinically diagnosed HCC. Results Exome sequencing revealed high mutation frequencies of AXIN2 and CTNNB1 in STX Hispanic HCCs, suggesting a predominant activation of the Wnt/β-catenin pathway. The TERT promoter mutation frequency was also remarkably high in the Hispanic cohort. Cell cycles and liver functions were identified as positively- and negatively-enriched, respectively, with gene set enrichment analysis. Gene sets representing specific liver metabolic pathways were associated with dysregulation of corresponding metabolites. Negative enrichment of liver adipogenesis and lipid metabolism corroborated with a significant reduction in most lipids in the serum samples of HCC patients. Two HCC subtypes from our Hispanic cohort were identified and validated with the TCGA liver cancer cohort. The subtype with better overall survival showed higher activity of immune and angiogenesis signatures, and lower activity of liver function-related gene signatures. It also had higher levels of immune checkpoint and immune exhaustion markers. Conclusions Our study revealed some specific molecular features of Hispanic HCC and potential biomarkers for therapeutic management of HCC and provides a unique resource for studying Hispanic HCC.
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Jiang J, Hu Y, Fang D, Luo J. Glutamine synthetase and hepatocellular carcinoma. Clin Res Hepatol Gastroenterol 2023; 47:102248. [PMID: 37979911 DOI: 10.1016/j.clinre.2023.102248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/02/2023] [Accepted: 11/15/2023] [Indexed: 11/20/2023]
Abstract
Glutamine synthetase (GS) is an enzyme that converts ammonia and glutamate to glutamine using adenosine triphosphate. GS is expressed in the brain, kidney, and liver tissues under normal physiological conditions. GS is involved in abnormal lipid metabolism of the liver by catalyzing de novo synthesis of glutamine, thereby inducing liver inflammation. Metabolic dysfunction-associated steatotic liver diseases (MASLD), such as Metabolic Associated Fatty Liver Disease and Metabolic Associated Steato Hepatitis, are considered risk factors for HCC. GS may also be involved in the development and progression of hepatocellular carcinoma (HCC) through other signaling pathways, including the rapamycin (mTOR) and Wnt/β-catenin signaling pathways. Furthermore, the correct combination of HSP70, GPC3, and GS can improve the accuracy and precision of HCC diagnosis. However, the prognostic value of GS in different HCC populations remains controversial. The expression of GS affects the sensitivity of HCC cells to radiotherapy and chemotherapy. In addition, immunotherapy has been approved for the treatment of advanced HCC. This article delves into the development and application of GS in HCC, laying a theoretical foundation for the subsequent exploration of GS as a potential target for treating HCC.
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Affiliation(s)
- Jinghua Jiang
- Department of Hepatobiliary and Pancreatic Surgery, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, Zhejiang 321000, China
| | - Yiting Hu
- Department of Hepatobiliary and Pancreatic Surgery, Shulan (Hangzhou) Hospital, Zhejiang Shuren University, Shulan International Medical College, Hangzhou, Zhejiang, China
| | - Dazhang Fang
- Department of Hepatobiliary and Pancreatic Surgery, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, Zhejiang 321000, China
| | - JianSheng Luo
- Department of Hepatobiliary and Pancreatic Surgery, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, Zhejiang 321000, China.
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6
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Journo S, Goldberg AK, Sokol ES, Zinger L, Pasmanik-Chor M, Sarvin B, Simkin D, Fuchs S, Shlomi T, Wolf I, Rubinek T. Genomic alterations drive metastases formation in pancreatic ductal adenocarcinoma cancer: deciphering the role of CDKN2A and CDKN2B in mediating liver tropism. Oncogene 2022; 41:1468-1481. [PMID: 35064215 DOI: 10.1038/s41388-022-02184-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 12/16/2021] [Accepted: 01/10/2022] [Indexed: 12/11/2022]
Abstract
Metastases are often the direct cause of death from pancreatic ductal adenocarcinoma (PDAC). The role of genomic alterations (GA) in mediating tropism and metastasis formation by PDAC cells is currently unknown. We aimed to identify GAs predisposing colonization of PDAC cells to the liver and decipher mechanisms enabling this process. In order to reveal specific genes, we studied the frequency of GA in 8,880 local and 7,983 metastatic PDAC samples. We observed differential pattern of GA in the local tumor and specific metastatic sites, with liver metastases characterized by deletion of CDKN2A/B (encoding p16/p15, respectively). The role of CDKN2A/B in promoting liver metastasis was evidenced by enhanced tumorigenic phenotype of p15/p16-deleted PDAC cells when exposed to hepatocytes conditioned media. The liver is characterized by high-ammonia low-glutamine environment and transcriptomic assays indicated unique adaptation of PDAC cells to these conditions, including regulation of genes leading to reduced glutaminolysis, like overexpression of GLUL and reduction in GLS2. Furthermore, metabolic assays indicated an increase in glutamate derived from [U-13C]-glucose in p15/p16-deleted cells. Importantly, these cells thrived under high ammonia condition. These data suggest a unique role for genomic alterations in mediating tropism of PDAC. Among these alterations, p15/16 deletion was identified as a promoter of liver metastases. Further studies indicated a unique role for p15/16 in regulating glutaminolysis. These findings reveal vulnerabilities in PDAC cells, which may pave the way for the development of novel therapeutic strategies aiming at the prevention of liver metastases formation.
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Affiliation(s)
- Shani Journo
- Institute of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | | | - Ethan S Sokol
- Foundation Medicine, Inc., Cambridge, MA, 02141, USA
| | - Lotem Zinger
- Institute of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Metsada Pasmanik-Chor
- Bioinformatics Unit, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Boris Sarvin
- Faculty of Computer Science at Technion; and Faculty of Biology at Technion, Haifa, Israel
| | - Dor Simkin
- Institute of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Sivan Fuchs
- Institute of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Tomer Shlomi
- Faculty of Computer Science at Technion; and Faculty of Biology at Technion, Haifa, Israel
| | - Ido Wolf
- Institute of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | - Tami Rubinek
- Institute of Oncology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
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7
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Loï C, Cynober L. Glutamate: A Safe Nutrient, Not Just a Simple Additive. ANNALS OF NUTRITION AND METABOLISM 2022; 78:133-146. [PMID: 35172302 DOI: 10.1159/000522482] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/04/2022] [Indexed: 11/19/2022]
Abstract
BACKGROUND In 2017, an European Food Safety Authority (EFSA) opinion on the use of glutamate and its salts as food additives led to an ADI of 30mg/kg body weight/day. Then, in 2021, an EFSA statement presented a proposal for harmonising the establishment of Health-Based Guidance Values for nutrients that are also regulated substances (including food additives). The present review argues that the 2017 glutamate ADI is unsuitable because safety of glutamate should firstly consider its status as a nutrient and not only as an additive. SUMMARY Glutamate is a non-essential amino acid playing a key role in nitrogen homeostasis. The dietary exposure to glutamate in adults is extensive, due to its ubiquitous presence in foods, under three forms: bound to proteins, naturally free and free form added as an additive. Glutamate naturally included into proteins is the major source of dietary glutamate. Thus, since it plays a role in nitrogen homeostasis, it is a nutrient before being an additive. Its pharmacokinetics is largely impacted by concomitant food intake but the extent to which plasma glutamate concentration must rise to have deleterious effects is never encountered in humans consuming glutamate in their daily diets. This is due to the fact that glutamate is highly metabolized in the splanchnic area. Key Messages: Glutamate should be considered as a safe nutrient before as an additive by risk assessor.
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Affiliation(s)
| | - Luc Cynober
- Laboratoire de Biologie de la Nutrition, URP 4466, Faculté de Pharmacie, Université de Paris, Paris, France
- Service de Biochimie, Hôpital Cochin, AP-HP, Paris, France
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Delgado TC, de las Heras J, Martínez-Chantar ML. Understanding gut-liver axis nitrogen metabolism in Fatty Liver Disease. Front Endocrinol (Lausanne) 2022; 13:1058101. [PMID: 36589817 PMCID: PMC9797658 DOI: 10.3389/fendo.2022.1058101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/21/2022] [Indexed: 12/23/2022] Open
Abstract
The homeostasis of the most important nitrogen-containing intermediates, ammonia and glutamine, is a tightly regulated process in which the gut-liver axis plays a central role. Several studies revealed that nitrogen metabolism is altered in Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD), a consensus-driven novel nomenclature for Non-Alcoholic Fatty Liver Disease (NAFLD), the most common chronic liver disease worldwide. Both increased ammonia production by gut microbiota and decreased ammonia hepatic removal due to impaired hepatic urea cycle activity or disrupted glutamine synthetase activity may contribute to hepatic ammonia accumulation underlying steatosis, which can eventually progress to hyperammonemia in more advanced stages of steatohepatitis and overt liver fibrosis. Furthermore, our group recently showed that augmented hepatic ammoniagenesis via increased glutaminase activity and overexpression of the high activity glutaminase 1 isoenzyme occurs in Fatty Liver Disease. Overall, the improved knowledge of disrupted nitrogen metabolism and metabolic miscommunication between the gut and the liver suggests that the reestablishment of altered gut-liver axis nitrogenous balance is an appealing and attractive therapeutic approach to tackle Fatty Liver Disease, a growing and unmet health problem.
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Affiliation(s)
- Teresa C. Delgado
- Liver Disease Lab, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Derio, Bizkaia, Spain
- Congenital Metabolic Disorders, Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
- *Correspondence: Teresa C. Delgado,
| | - Javier de las Heras
- Congenital Metabolic Disorders, Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
- Division of Pediatric Metabolism, Department of Pediatrics, CIBERer, Cruces University Hospital, Barakaldo, Spain
- Department of Pediatrics, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - María L. Martínez-Chantar
- Liver Disease Lab, Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Derio, Bizkaia, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Carlos III National Health Institute, Madrid, Spain
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9
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Morales A, González F, Bernal H, Camacho RL, Arce N, Vásquez N, González-Vega JC, Htoo JK, Viana MT, Cervantes M. Effect of arginine supplementation on the morphology and function of intestinal epithelia, and serum concentrations of amino acids in pigs exposed to heat stress. J Anim Sci 2021; 99:6291043. [PMID: 34077525 DOI: 10.1093/jas/skab179] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/31/2021] [Indexed: 11/13/2022] Open
Abstract
The exposure of pigs to heat stress (HS) appears to damage their intestinal epithelia, affecting the absorption of amino acids (AA). Arg is involved in the restoration of intestinal epithelial cells but HS reduces Arg intake. The effect of dietary supplementation with Arg on morphology of intestinal epithelia, AA transporter gene expression, and serum concentration (SC) of free AA in HS pigs were analyzed. Twenty pigs (25.3 ± 2.4 kg BW) were randomly assigned to two dietary treatments: control (0.81% Arg), wheat-soybean meal diet supplemented with L-Lys, L-Thr, DL-Met and L-Trp, and the experimental diet where 0.16% free L-Arg was supplemented to a similar control diet (+Arg). All pigs were individually housed and exposed to HS, fed at libitum with full access to water. The ambient temperature, recorded at 15-min intervals during the 21-d trial, ranged on average from 29.6 to 39.4 °C within the same day. Blood samples were collected on d18 at 1600 h (ambient temperature peak); serum was separated by centrifugation. At the end of the trial, five pigs per treatment were sacrificed to collect samples of mucosa scratched from each small intestine segment. The expression of AA transporters in intestinal mucosa and the SC of AA were analyzed. Villi height was higher (P < 0.01) in duodenum, jejunum, and ileum but the crypt depth did not differ between the control and the +Arg pigs. Supplementation of L-Arg increased the mRNA coding for the synthesis of the cationic AA transporter b 0,+ (P < 0.01) and the neutral AA transporter B 0 (P < 0.05) in duodenum by approximately five-folds and three-folds, respectively, but no effect on mRNA abundance was observed in jejunum and ileum. The supplementation of L-Arg increased serum Arg, His, Met, Thr, Trp, and urea (P < 0.05); tended to increase Val (P < 0.10), but did not affect Ile, Lys, Leu, and Phe. These results indicate that supplementing 0.16% L-Arg to the control diet may help to improve the function of the small intestine epithelium, by increasing the villi height, the abundance of AA transporters, and the SC of most indispensable AA in pigs exposed to HS conditions. However, the lack of effect of supplemental Arg on both Lys SC and weight gain of pigs suggests that increasing the Lys content in the +Arg diet might be needed to improve the performance of HS pigs.
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Affiliation(s)
- A Morales
- Universidad Autónoma de Baja California, Mexicali, B. C., México
| | - F González
- Universidad Autónoma de Baja California, Mexicali, B. C., México
| | - H Bernal
- Universidad Autónoma de Nuevo León, Monterrey, México
| | - R L Camacho
- Universidad Autónoma de Baja California, Mexicali, B. C., México
| | - N Arce
- Universidad Autónoma de Baja California, Mexicali, B. C., México
| | - N Vásquez
- Universidad Autónoma de Nuevo León, Monterrey, México
| | | | - J K Htoo
- Evonik Operations GmbH, Hanau, Germany
| | - M T Viana
- Universidad Autónoma de Baja California, Mexicali, B. C., México
| | - M Cervantes
- Universidad Autónoma de Baja California, Mexicali, B. C., México
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10
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Glutamine Synthetase as a Therapeutic Target for Cancer Treatment. Int J Mol Sci 2021; 22:ijms22041701. [PMID: 33567690 PMCID: PMC7915753 DOI: 10.3390/ijms22041701] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/29/2021] [Accepted: 02/04/2021] [Indexed: 12/15/2022] Open
Abstract
The significance of glutamine in cancer metabolism has been extensively studied. Cancer cells consume an excessive amount of glutamine to facilitate rapid proliferation. Thus, glutamine depletion occurs in various cancer types, especially in poorly vascularized cancers. This makes glutamine synthetase (GS), the only enzyme responsible for de novo synthesizing glutamine, essential in cancer metabolism. In cancer, GS exhibits pro-tumoral features by synthesizing glutamine, supporting nucleotide synthesis. Furthermore, GS is highly expressed in the tumor microenvironment (TME) and provides glutamine to cancer cells, allowing cancer cells to maintain sufficient glutamine level for glutamine catabolism. Glutamine catabolism, the opposite reaction of glutamine synthesis by GS, is well known for supporting cancer cell proliferation via contributing biosynthesis of various essential molecules and energy production. Either glutamine anabolism or catabolism has a critical function in cancer metabolism depending on the complex nature and microenvironment of cancers. In this review, we focus on the role of GS in a variety of cancer types and microenvironments and highlight the mechanism of GS at the transcriptional and post-translational levels. Lastly, we discuss the therapeutic implications of targeting GS in cancer.
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Interorgan Metabolism of Amino Acids in Human Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1332:129-149. [PMID: 34251642 DOI: 10.1007/978-3-030-74180-8_8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Amino acids are integral for human health, influencing an array of physiological processes from gene expression to vasodilation to the immune response. In accordance with this expansive range of unique functions, the tissues of the body engage in a complex interplay of amino acid exchange and metabolism to respond to the organism's dynamic needs for a range of nitrogenous products. Interorgan amino acid metabolism is required for numerous metabolic pathways, including the synthesis of functional amino acids like arginine, glutamate, glutamine, and glycine. This physiological process requires the cooperative handling of amino acids by organs (e.g., the small intestine, skeletal muscle, kidneys, and liver), as well as the complete catabolism of nutritionally essential amino acids such as the BCAAs, with their α-ketoacids shuttled from muscle to liver. These exchanges are made possible by several mechanisms, including organ location, as well as the functional zonation of enzymes and the cell-specific expression of amino acid transporters. The cooperative handling of amino acids between the various organs does not appear to be under the control of any centralized regulation, but is instead influenced by factors such as fluctuations in nutrient availability, hormones, changes associated with development, and altered environmental factors. While the normal function of these pathways is associated with health and homeostasis, affected by physical activity, diet and body composition, dysregulation is observed in numerous disease states, including cardiovascular disease and cancer cachexia, presenting potential avenues for the manipulation of amino acid consumption as part of the therapeutic approach to these conditions in individuals.
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12
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He W, Furukawa K, Toyomizu M, Nochi T, Bailey CA, Wu G. Interorgan Metabolism, Nutritional Impacts, and Safety of Dietary L-Glutamate and L-Glutamine in Poultry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1332:107-128. [PMID: 34251641 DOI: 10.1007/978-3-030-74180-8_7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
L-glutamine (Gln) is the most abundant amino acid (AA) in the plasma and skeletal muscle of poultry, and L-glutamate (Glu) is among the most abundant AAs in the whole bodies of all avian tissues. During the first-pass through the small intestine into the portal circulation, dietary Glu is extensively oxidized to CO2, but dietary Gln undergoes limited catabolism in birds. Their extra-intestinal tissues (e.g., skeletal muscle, kidneys, and lymphoid organs) have a high capacity to degrade Gln. To maintain Glu and Gln homeostasis in the body, they are actively synthesized from branched-chain AAs (abundant AAs in both plant and animal proteins) and glucose via interorgan metabolism involving primarily the skeletal muscle, heart, adipose tissue, and brain. In addition, ammonia (produced from the general catabolism of AAs) and α-ketoglutarate (α-KG, derived primarily from glucose) serve as substrates for the synthesis of Glu and Gln in avian tissues, particularly the liver. Over the past 20 years, there has been growing interest in Glu and Gln metabolism in the chicken, which is an agriculturally important species and also a useful model for studying some aspects of human physiology and diseases. Increasing evidence shows that the adequate supply of dietary Glu and Gln is crucial for the optimum growth, anti-oxidative responses, productivity, and health of chickens, ducklings, turkeys, and laying fowl, particularly under stress conditions. Like mammals, poultry have dietary requirements for both Glu and Gln. Based on feed intake, tissue integrity, growth performance, and health status, birds can tolerate up to 12% Glu and 3.5% Gln in diets (on the dry matter basis). Glu and Gln are quantitatively major nutrients for chickens and other avian species to support their maximum growth, production, and feed efficiency, as well as their optimum health and well-being.
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Affiliation(s)
- Wenliang He
- Departments of Animal Science, Texas A&M University, College Station, TX, 77843, USA
| | - Kyohei Furukawa
- Departments of Animal Science, Texas A&M University, College Station, TX, 77843, USA.,Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Masaaki Toyomizu
- Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Tomonori Nochi
- Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Christopher A Bailey
- Departments of Poultry Science, Texas A&M University, College Station, TX, 77843, USA
| | - Guoyao Wu
- Departments of Animal Science, Texas A&M University, College Station, TX, 77843, USA.
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Cavino K, Sung B, Su Q, Na E, Kim J, Cheng X, Gromada J, Okamoto H. Glucagon Receptor Inhibition Reduces Hyperammonemia and Lethality in Male Mice with Urea Cycle Disorder. Endocrinology 2021; 162:5988952. [PMID: 33206168 DOI: 10.1210/endocr/bqaa211] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Indexed: 12/14/2022]
Abstract
The liver plays a critical role in maintaining ammonia homeostasis. Urea cycle defects, liver injury, or failure and glutamine synthetase (GS) deficiency result in hyperammonemia, serious clinical conditions, and lethality. In this study we used a mouse model with a defect in the urea cycle enzyme ornithine transcarbamylase (Otcspf-ash) to test the hypothesis that glucagon receptor inhibition using a monoclonal blocking antibody will reduce the hyperammonemia and associated lethality induced by a high-protein diet, which exacerbates disease. We found reduced expression of glutaminase, which degrades glutamine and increased expression of GS in livers of Otcspf-ash mice treated with the glucagon receptor blocking antibody. The gene expression changes favor ammonia consumption and were accompanied by increased circulating glutamine levels and diminished hyperammonemia. Otcspf-ash mice treated with the glucagon receptor-blocking antibody gained lean and body mass and had increased survival. These data suggest that glucagon receptor inhibition using a monoclonal antibody could reduce the risk for hyperammonemia and other clinical manifestations of patients suffering from defects in the urea cycle, liver injury, or failure and GS deficiency.
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Affiliation(s)
- Katie Cavino
- Regeneron Pharmaceuticals, Tarrytown, New York USA
| | - Biin Sung
- Regeneron Pharmaceuticals, Tarrytown, New York USA
| | - Qi Su
- Regeneron Pharmaceuticals, Tarrytown, New York USA
| | - Erqian Na
- Regeneron Pharmaceuticals, Tarrytown, New York USA
| | - Jinrang Kim
- Regeneron Pharmaceuticals, Tarrytown, New York USA
| | - Xiping Cheng
- Regeneron Pharmaceuticals, Tarrytown, New York USA
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14
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Jiménez-Torres C, Hernández-Kelly LC, Najimi M, Ortega A. Bisphenol A exposure disrupts aspartate transport in HepG2 cells. J Biochem Mol Toxicol 2020; 34:e22516. [PMID: 32363662 DOI: 10.1002/jbt.22516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 03/17/2020] [Accepted: 04/22/2020] [Indexed: 01/01/2023]
Abstract
The liver is the organ responsible for bisphenol A (BPA) metabolism, an environmental chemical agent. Exposure to this toxin is associated with liver abnormalities and dysfunction. An important role played by excitatory amino acid transporters (EAATs) of the slc1 gene family has been reported in liver injuries. To gain insight into a plausible effect of BPA exposure in the liver glutamate/aspartate transport, using the human hepatoblastoma cell line HepG2, we report a BPA-dependent dynamic regulation of SLC1A3 and SLC1A2. Through the use of radioactive [3 H]- d-aspartate uptake experiments and immunochemical approaches, we characterized time and dose-dependent regulation of the protein levels and function of these transporters after acute exposure to BPA. An increase in nuclear Yin Yang 1 was found. These results suggest an important involvement of the EAATs in liver physiology and its disruption after acute BPA exposure.
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Affiliation(s)
- Catya Jiménez-Torres
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, México
| | - Luisa C Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, México
| | - Mustapha Najimi
- Hepato-Gastroenterolgy Research Pole, Laboratory of Pediatric Hepatology and Cell Therapy, Institut de Recherche Expérimentale et Clinique (IREC), Université́ Catholique de Louvain, Brussels, Belgium
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Ciudad de México, México
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15
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Pedersen C, Kraft G, Edgerton DS, Scott M, Farmer B, Smith M, Laneve DC, Williams PE, Moore LM, Cherrington AD. The kinetics of glucagon action on the liver during insulin-induced hypoglycemia. Am J Physiol Endocrinol Metab 2020; 318:E779-E790. [PMID: 32208001 PMCID: PMC7272728 DOI: 10.1152/ajpendo.00466.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glucagon's effect on hepatic glucose production (HGP), under hyperglycemic conditions, is time dependent such that after an initial burst of HGP, it slowly wanes. It is not known whether this is also the case under hypoglycemic conditions, where an increase in HGP is essential. This question was addressed using adrenalectomized dogs to avoid the confounding effects of other counterregulatory hormones. During the study, infusions of epinephrine and cortisol were given to maintain basal levels. Somatostatin and insulin (800 µU·kg-1·min-1) were infused to induce hypoglycemia. After 30 min, glucagon was infused at a basal rate (1 ng·kg-1·min-1, baGGN group, n = 5 dogs) or a rate eightfold basal (8 ng·kg-1·min-1, hiGGN group, n = 5 dogs) for 4 h. Glucose was infused to match the arterial glucose levels between groups (≈50 mg/dL). Our data showed that glucagon has a biphasic effect on the liver despite hypoglycemia. Hyperglucagonemia stimulated a rapid, transient peak in HGP (4-fold basal production) over ~60 min, which was followed by a slow reduction in HGP to a rate 1.5-fold basal. During the last 2 h of the experiment, hiGGN stimulated glucose production at a rate fivefold greater than baGGN (2.5 vs. 0.5 mg·kg-1·min-1, respectively), indicating a sustained effect of the hormone. Of note, the hypoglycemia-induced rises in norepinephrine and glycerol were smaller in hiGGN compared with the baGGN group despite identical hypoglycemia. This finding suggests that there is reciprocity between glucagon and the sympathetic nervous system such that when glucagon is increased, the sympathetic nervous response to hypoglycemia is downregulated.
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Affiliation(s)
| | - Guillaume Kraft
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Dale S Edgerton
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Melanie Scott
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Ben Farmer
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Marta Smith
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - David C Laneve
- Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Phillip E Williams
- Section of Surgical Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - L Merkle Moore
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Alan D Cherrington
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, Tennessee
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16
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Lamade AM, Anthonymuthu TS, Hier ZE, Gao Y, Kagan VE, Bayır H. Mitochondrial damage & lipid signaling in traumatic brain injury. Exp Neurol 2020; 329:113307. [PMID: 32289317 DOI: 10.1016/j.expneurol.2020.113307] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/09/2020] [Accepted: 04/10/2020] [Indexed: 12/13/2022]
Abstract
Mitochondria are essential for neuronal function because they serve not only to sustain energy and redox homeostasis but also are harbingers of death. A dysregulated mitochondrial network can cascade until function is irreparably lost, dooming cells. TBI is most prevalent in the young and comes at significant personal and societal costs. Traumatic brain injury (TBI) triggers a biphasic and mechanistically heterogenous response and this mechanistic heterogeneity has made the development of standardized treatments challenging. The secondary phase of TBI injury evolves over hours and days after the initial insult, providing a window of opportunity for intervention. However, no FDA approved treatment for neuroprotection after TBI currently exists. With recent advances in detection techniques, there has been increasing recognition of the significance and roles of mitochondrial redox lipid signaling in both acute and chronic central nervous system (CNS) pathologies. Oxidized lipids and their downstream products result from and contribute to TBI pathogenesis. Therapies targeting the mitochondrial lipid composition and redox state show promise in experimental TBI and warrant further exploration. In this review, we provide 1) an overview for mitochondrial redox homeostasis with emphasis on glutathione metabolism, 2) the key mechanisms of TBI mitochondrial injury, 3) the pathways of mitochondria specific phospholipid cardiolipin oxidation, and 4) review the mechanisms of mitochondria quality control in TBI with consideration of the roles lipids play in this process.
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Affiliation(s)
- Andrew M Lamade
- Department of Critical Care Medicine, Safar Center for Resuscitation Research UPMC, Pittsburgh, PA, USA; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Tamil S Anthonymuthu
- Department of Critical Care Medicine, Safar Center for Resuscitation Research UPMC, Pittsburgh, PA, USA; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Zachary E Hier
- Department of Critical Care Medicine, Safar Center for Resuscitation Research UPMC, Pittsburgh, PA, USA; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Yuan Gao
- Department of Critical Care Medicine, Safar Center for Resuscitation Research UPMC, Pittsburgh, PA, USA; Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Valerian E Kagan
- Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA; Institute for Regenerative Medicine, IM Sechenov First Moscow State Medical University, Russian Federation
| | - Hülya Bayır
- Department of Critical Care Medicine, Safar Center for Resuscitation Research UPMC, Pittsburgh, PA, USA; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA, USA; Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA.
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17
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Bayır H, Anthonymuthu TS, Tyurina YY, Patel SJ, Amoscato AA, Lamade AM, Yang Q, Vladimirov GK, Philpott CC, Kagan VE. Achieving Life through Death: Redox Biology of Lipid Peroxidation in Ferroptosis. Cell Chem Biol 2020; 27:387-408. [PMID: 32275865 DOI: 10.1016/j.chembiol.2020.03.014] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 03/02/2020] [Accepted: 03/17/2020] [Indexed: 12/11/2022]
Abstract
Redox balance is essential for normal brain, hence dis-coordinated oxidative reactions leading to neuronal death, including programs of regulated death, are commonly viewed as an inevitable pathogenic penalty for acute neuro-injury and neurodegenerative diseases. Ferroptosis is one of these programs triggered by dyshomeostasis of three metabolic pillars: iron, thiols, and polyunsaturated phospholipids. This review focuses on: (1) lipid peroxidation (LPO) as the major instrument of cell demise, (2) iron as its catalytic mechanism, and (3) thiols as regulators of pro-ferroptotic signals, hydroperoxy lipids. Given the central role of LPO, we discuss the engagement of selective and specific enzymatic pathways versus random free radical chemical reactions in the context of the phospholipid substrates, their biosynthesis, intracellular location, and related oxygenating machinery as participants in ferroptotic cascades. These concepts are discussed in the light of emerging neuro-therapeutic approaches controlling intracellular production of pro-ferroptotic phospholipid signals and their non-cell-autonomous spreading, leading to ferroptosis-associated necroinflammation.
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Affiliation(s)
- Hülya Bayır
- Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA; Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15224, USA.
| | - Tamil S Anthonymuthu
- Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA; Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Yulia Y Tyurina
- Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Sarju J Patel
- Genetics and Metabolism Section, Liver Diseases Branch, NIDDK, NIH, Bethesda, MD 20892, USA
| | - Andrew A Amoscato
- Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Andrew M Lamade
- Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA; Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Qin Yang
- Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA; Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Safar Center for Resuscitation Research, Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15224, USA
| | - Georgy K Vladimirov
- Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Institute for Regenerative Medicine, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Caroline C Philpott
- Genetics and Metabolism Section, Liver Diseases Branch, NIDDK, NIH, Bethesda, MD 20892, USA
| | - Valerian E Kagan
- Children's Neuroscience Institute, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA 15224, USA; Center for Free Radical and Antioxidant Health, Department of Environmental Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Institute for Regenerative Medicine, Sechenov First Moscow State Medical University, 119991 Moscow, Russia.
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18
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Schwarz H, Zhang Y, Zhan C, Malm M, Field R, Turner R, Sellick C, Varley P, Rockberg J, Chotteau V. Small-scale bioreactor supports high density HEK293 cell perfusion culture for the production of recombinant Erythropoietin. J Biotechnol 2020; 309:44-52. [DOI: 10.1016/j.jbiotec.2019.12.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 12/11/2019] [Accepted: 12/26/2019] [Indexed: 12/26/2022]
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19
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Glutamine/glutamate metabolism rewiring in reprogrammed human hepatocyte-like cells. Sci Rep 2019; 9:17978. [PMID: 31784643 PMCID: PMC6884617 DOI: 10.1038/s41598-019-54357-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 11/13/2019] [Indexed: 12/19/2022] Open
Abstract
Human dermal fibroblasts can be reprogrammed into hepatocyte-like (HEP-L) cells by the expression of a set of transcription factors. Yet, the metabolic rewiring suffered by reprogrammed fibroblasts remains largely unknown. Here we report, using stable isotope-resolved metabolic analysis in combination with metabolomic-lipidomic approaches that HEP-L cells mirrors glutamine/glutamate metabolism in primary cultured human hepatocytes that is very different from parental human fibroblasts. HEP-L cells diverge glutamine from multiple metabolic pathways into deamidation and glutamate secretion, just like periportal hepatocytes do. Exceptionally, glutamine contribution to lipogenic acetyl-CoA through reductive carboxylation is increased in HEP-L cells, recapitulating that of primary cultured human hepatocytes. These changes can be explained by transcriptomic rearrangements of genes involved in glutamine/glutamate metabolism. Although metabolic changes in HEP-L cells are in line with reprogramming towards the hepatocyte lineage, our conclusions are limited by the fact that HEP-L cells generated do not display a complete mature phenotype. Nevertheless, our findings are the first to characterize metabolic adaptation in HEP-L cells that could ultimately be targeted to improve fibroblasts direct reprogramming to HEP-L cells.
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Lin CY, Huang LH, Deng DF, Lee SH, Liang HJ, Hung SSO. Metabolic adaptation to feed restriction on the green sturgeon (Acipenser medirostris) fingerlings. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 684:78-88. [PMID: 31150878 DOI: 10.1016/j.scitotenv.2019.05.044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/03/2019] [Accepted: 05/04/2019] [Indexed: 06/09/2023]
Abstract
Food restriction may cause severe biological effects on wildlife and lead to population decline and extinction. The objective of the current study was to examine the metabolic effects on green sturgeon in response to feed restriction. Green sturgeon fingerlings were fed for two weeks at 12.5, 25, 50 and 100% of the optimum feeding rate (OFR), which corresponded to 0.25, 0.50, 1.00, and 2.00% body weight per day. We characterized the changes in hydrophilic and hydrophobic metabolites from extracts of muscle, liver, and kidney using nuclear magnetic resonance spectroscopy followed by multivariate statistical analysis. The results of principal component analysis (PCA) score plots from the analyses of hydrophilic metabolites showed that they exhibited a greater response to feed restriction than hydrophobic metabolites. In general, the hydrophilic metabolites in tissues from fish fed ≦25% of the OFR were separated from those fed 100% of the OFR in the PCA score plots. Among the three types of tissues examined, the overall metabolite changes showed a greater response to feed restriction in kidney tissue than in liver or muscle tissues. Numerous glucogenic amino acids in muscle and most amino acids in the kidney were decreased under feed restriction conditions. A significant decrease in ketone bodies (3-hydroxyisobutyrate) was observed in the muscle. Most fatty acids except for glycerol, phospholipid and cholesterol in the liver and kidney tissues were decreased under feed restriction conditions. Creatine phosphate, taurine and glycine were also significantly increased in tissues under feed restriction conditions. In conclusion, this study suggests that the manipulation of feed restriction under the current conditions perturbed metabolites related to energy metabolism, osmolality regulation, and antioxidation capacity in the sturgeon.
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Affiliation(s)
- Ching-Yu Lin
- Institute of Environmental Health, College of Public Health, National Taiwan University, Taipei, Taiwan, ROC.
| | - Lu-Hsueh Huang
- Institute of Environmental Health, College of Public Health, National Taiwan University, Taipei, Taiwan, ROC
| | - Dong-Fang Deng
- School of Freshwater Sciences, University of Wisconsin, Milwaukee, WI 53204, USA
| | - Sheng-Han Lee
- Institute of Environmental Health, College of Public Health, National Taiwan University, Taipei, Taiwan, ROC
| | - Hao-Jan Liang
- Institute of Environmental Health, College of Public Health, National Taiwan University, Taipei, Taiwan, ROC
| | - Silas S O Hung
- Department of Animal Science, University of California, Davis 95616, USA
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21
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Souza RRD, Pacheco CF, Caperuto EC, Maifrino LB, Gama EF. Glutamine supplementation influences the secretory apparatus in the right atrial cardiomyocytes of resistance trained aged rats. REVISTA BRASILEIRA DE CIÊNCIAS DO ESPORTE 2019. [DOI: 10.1016/j.rbce.2018.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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22
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Adler M, Korem Kohanim Y, Tendler A, Mayo A, Alon U. Continuum of Gene-Expression Profiles Provides Spatial Division of Labor within a Differentiated Cell Type. Cell Syst 2019; 8:43-52.e5. [DOI: 10.1016/j.cels.2018.12.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/01/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
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23
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Huang J, Jia Y, Li Q, Burris WR, Bridges PJ, Matthews JC. Hepatic glutamate transport and glutamine synthesis capacities are decreased in finished vs. growing beef steers, concomitant with increased GTRAP3-18 content. Amino Acids 2018; 50:513-525. [PMID: 29392419 PMCID: PMC5917004 DOI: 10.1007/s00726-018-2540-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 01/22/2018] [Indexed: 01/17/2023]
Abstract
Hepatic glutamate uptake and conversion to glutamine is critical for whole-body N metabolism, but how this process is regulated during growth is poorly described. The hepatic glutamate uptake activities, protein content of system [Formula: see text] transporters (EAAC1, GLT-1) and regulatory proteins (GTRAP3-18, ARL6IP1), glutamine synthetase (GS) activity and content, and glutathione (GSH) content, were compared in liver tissue of weaned Angus steers randomly assigned (n = 8) to predominantly lean (growing) or predominantly lipid (finished) growth regimens. Steers were fed a cotton seed hull-based diet to achieve final body weights of 301 or 576 kg, respectively, at a constant rate of growth. Liver tissue was collected at slaughter and hepatic membranes fractionated. Total (75%), Na+-dependent (90%), system [Formula: see text]-dependent (abolished) glutamate uptake activity, and EAAC1 content (36%) in canalicular membrane-enriched vesicles decreased as steers developed from growing (n = 6) to finished (n = 4) stages, whereas Na+-independent uptake did not change. In basolateral membrane-enriched vesicles, total (60%), Na+-dependent (60%), and Na+-independent (56%) activities decreased, whereas neither system [Formula: see text]-dependent uptake nor protein content changed. EAAC1 protein content in liver homogenates (n = 8) decreased in finished vs. growing steers, whereas GTRAP3-18 and ARL6IP1 content increased and GLT-1 content did not change. Concomitantly, hepatic GS activity decreased (32%) as steers fattened, whereas GS and GSH contents did not differ. We conclude that hepatic glutamate uptake and GS synthesis capacities are reduced in livers of finished versus growing beef steers, and that hepatic system [Formula: see text] transporter activity/EAAC1 content is inversely proportional to GTRAP3-18 content.
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Affiliation(s)
- J Huang
- Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA
| | - Y Jia
- Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA
| | - Q Li
- Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA
| | - W R Burris
- Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA
| | - P J Bridges
- Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA
| | - J C Matthews
- Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA.
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24
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Hu R, Qu F, Tang J, Zhao Q, Yan J, Zhou Z, Zhou Y, Liu Z. Cloning, expression, and nutritional regulation of the glutamine synthetase gene in Ctenopharyngodon idellus. Comp Biochem Physiol B Biochem Mol Biol 2017. [DOI: 10.1016/j.cbpb.2017.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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25
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Wang S, Xiang YY, Zhu J, Yi F, Li J, Liu C, Lu WY. Protective roles of hepatic GABA signaling in acute liver injury of rats. Am J Physiol Gastrointest Liver Physiol 2017; 312:G208-G218. [PMID: 27979827 DOI: 10.1152/ajpgi.00344.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 12/05/2016] [Accepted: 12/12/2016] [Indexed: 01/31/2023]
Abstract
γ-Aminobutyric acid (GABA) is produced by various cells through the catalytic activity of glutamic acid decarboxylase (GAD). Activation of type-A GABA receptor (GABAAR) inhibits stem cell proliferation but protects differentiated cells from injures. The present study investigated hepatic GABA signaling system and the role of this system in liver physiology and pathophysiology. RT-PCR and immunoblot assays identified GAD and GABAAR subunits in rat livers and in HepG2 and Clone 9 hepatocytes. Patch-clamp recording detected GABA-induced currents in Clone 9 hepatocytes and depolarization in WITT cholangiocytes. The function of hepatic GABA signaling system in rats was examined using models of d-galactosamine (GalN)-induced acute hepatocytic injury in vivo and in vitro. The expression of GAD increased whereas GABAAR subunits decreased in the liver of GalN-treated rats. Remarkably, treating rats with GABA or the GABAAR agonist muscimol, but not the GABABR agonist baclofen, protected hepatocytes against GalN toxicity and improved liver function. In addition, muscimol treatment decreased the formation of pseudobile ductules and the enlargement of hepatocytic canaliculi in GalN-treated rats. Our results revealed that a complex GABA signaling system exists in the rat liver. Activation of this intrahepatic GABAergic system protected the liver against toxic injury.NEW & NOTEWORTHY Auto- and paracrine GABAergic signaling systems exist in the rat hepatocytes and cholangiocytes. Activation of GABA signaling protects liver function from d-galactosamine injury by reducing toxic impairment of hepatocytes and by decreasing cholangiocyte proliferation.
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Affiliation(s)
- Shuanglian Wang
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China.,Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.,Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.,Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada; and
| | - Yun-Yan Xiang
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada.,Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.,Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada; and
| | - Jianchun Zhu
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Fan Yi
- Department of Pharmacology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Jingxin Li
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China.,Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada; and
| | - Chuanyong Liu
- Department of Physiology, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China;
| | - Wei-Yang Lu
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada; .,Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.,Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, Canada; and
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Comar JF, de Oliveira DS, Bracht L, Kemmelmeier FS, Peralta RM, Bracht A. The Metabolic Responses to L-Glutamine of Livers from Rats with Diabetes Types 1 and 2. PLoS One 2016; 11:e0160067. [PMID: 27490892 PMCID: PMC4973899 DOI: 10.1371/journal.pone.0160067] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 07/12/2016] [Indexed: 11/18/2022] Open
Abstract
There are several claims about the beneficial effects of supplementing L-glutamine to both type 1 and type 2 diabetes. The purpose of the present study was to provide detailed knowledge about the fate of this amino acid in the liver, the first organ that receives the compound when ingested orally. The study was done using the isolated perfused rat liver, an experimental system that preserves the microcirculation of the organ and that allows to measured several parameters during steady-state and pre steady-state conditions. L-Glutamine was infused in the portal vein (5 mM) and several parameters were monitored. Livers from type 1 diabetic rats showed an accelerated response to L-glutamine infusion. In consequence of this accelerated response livers from type 1 diabetic rats presented higher rates of ammonia, urea, glucose and lactate output during the first 25–30 minutes following L-glutamine infusion. As steady-state conditions approached, however, the difference between type 1 diabetes and control livers tended to disappear. Measurement of the glycogen content over a period of 100 minutes revealed that, excepting the initial phase of the L-glutamine infusion, the increased glucose output in livers from type 1 diabetic rats was mainly due to accelerated glycogenolysis. Livers from type 2 diabetic rats behaved similarly to control livers with no accelerated glucose output but with increased L-alanine production. L-Alanine is important for the pancreatic β-cells and from this point of view the oral intake of L-glutamine can be regarded as beneficial. Furthermore, the lack of increased glucose output in livers from type 2 diabetic rats is consistent with observations that even daily L-glutamine doses of 30 g do not increase the glycemic levels in well controlled type 2 diabetes patients.
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Affiliation(s)
| | | | - Livia Bracht
- Laboratory of Liver Metabolism, University of Maringá, 87020900 Maringá, Brazil
| | | | | | - Adelar Bracht
- Laboratory of Liver Metabolism, University of Maringá, 87020900 Maringá, Brazil
- * E-mail:
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Miles ED, McBride BW, Jia Y, Liao SF, Boling JA, Bridges PJ, Matthews JC. Glutamine synthetase and alanine transaminase expression are decreased in livers of aged vs. young beef cows and GS can be upregulated by 17β-estradiol implants. J Anim Sci 2016; 93:4500-9. [PMID: 26440349 DOI: 10.2527/jas.2015-9294] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Aged beef cows (≥ 8 yr of age) produce calves with lower birth and weaning weights. In mammals, aging is associated with reduced hepatic expression of glutamine synthetase (GS) and alanine transaminase (ALT), thus impaired hepatic Gln-Glu cycle function. To determine if the relative protein content of GS, ALT, aspartate transaminase (AST), glutamate transporters (EAAC1, GLT-1), and their regulating protein (GTRAP3-18) differed in biopsied liver tissue of (a) aged vs. young (3 to 4 yr old) nonlactating, nongestating Angus cows (Exp. 1 and 2) and (b) aged mixed-breed cows with and without COMPUDOSE (17β-estradiol) ear implants (Exp. 3), Western blot analyses were performed. In Exp. 1, 12 young (3.62 ± 0.01 yr) and 13 aged (10.08 ± 0.42 yr) cows grazed the same mixed forage for 42 d (August-October). In Exp. 2, 12 young (3.36 ± 0.01 yr) and 12 aged (10.38 ± 0.47 yr) cows were individually fed (1.03% of BW) a corn-silage-based diet to maintain BW for 20 d. For both Exp. 1 and 2, the effect of cow age was assessed by ANOVA using the MIXED procedure of SAS. Cow BW did not change ( ≥ 0.17). Hepatic ALT (78% and 61%) and GS (52% and 71%) protein content (Exp. 1 and 2, respectively) was decreased ( ≤ 0.01), whereas GTRAP3-18 (an inhibitor of EAAC1 activity) increased ( ≤ 0.01; 170% and 136%) and AST, GLT-1, and EAAC1 contents did not differ ( ≥ 0.17) in aged vs. young cows. In Exp. 2, free concentrations (nmol/g) of Glu, Ala, Gln, Arg, and Orn in liver homogenates were determined. Aged cows tended to have less ( = 0.10) free Gln (15.0%) than young cows, whereas other AA concentrations did not differ ( 0.26). In Exp. 3, 14 aged (> 10 yr) cows were randomly allotted ( = 7) to sham or COMPUDOSE (25.7 mg of 17β-estradiol) implant treatment (TRT), and had ad libitum access to alfalfa hay for 28 d. Blood and liver biopsies were collected 14 and 28 d after implant treatment. Treatment, time after implant (DAY), and TRT × DAY effects were assessed by ANOVA using the MIXED procedure of SAS. Cow BW was not affected ( ≥ 0.96). Implant increased ( ≤ 0.02) total plasma estradiol by 220% (5.07 vs. 1.58 pg/mL) and GS protein by 300%, whereas the relative content of other proteins was not altered ( ≥ 0.16). We conclude that hepatic expression of ALT and GS are reduced in aged vs. young cows, and administration of 17β-estradiol to aged cows increases plasma estradiol and hepatic GS, but not that of other proteins that support hepatic Glu metabolism.
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Alanyl-glutamine supplementation regulates mTOR and ubiquitin proteasome proteolysis signaling pathways in piglets. Nutrition 2016; 32:1123-31. [PMID: 27155955 DOI: 10.1016/j.nut.2016.02.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 02/03/2016] [Accepted: 02/25/2016] [Indexed: 10/22/2022]
Abstract
OBJECTIVE The aim of the present study was to investigate the effects of the alanyl-glutamine dipeptide (Ala-Gln) or the combination supplementation of free alanine and glutamine (Ala+Gln) on the mammalian target of rapamycin (mTOR) and ubiquitin-proteasome proteolysis (UPP) signaling pathways in piglets. METHODS We randomly allocated 180 piglets to three treatments with three replicates of 20 piglets each, fed with diets containing 0.62% Ala, 0.5% Ala-Gln, 0.21% Ala+0.34% Gln, respectively. The duration of the experiment was 28 d. RESULTS The results showed that Ala-Gln increased average daily gain of piglets, and decreased the ratio of feed to gain (P < 0.05). Ala-Gln supplementation increased the concentrations of Gln and glutamate and decreased the activity of glutamine synthetase in liver and skeletal muscle (P < 0.05). Ala-Gln increased the expression of glutaminase and glutamate dehydrogenate (P < 0.05). The increased phosphorylation of eIF-4 E binding protein 1 (4E-BP1) and ribosomal protein S6 kinase 1 (S6K1) in Ala-Gln treatment were associated with phosphorylation of the mTOR in liver and skeletal muscle. Ala+Gln did not affect the phosphorylation abundances of mTOR, 4E-BP1, or S6K1 (P > 0.05). Ala-Gln supplementation inhibited the mRNA expressions of MAFbx and MuRF1 in skeletal muscle of piglets (P < 0.05). CONCLUSION Taken together, Ala-Gln supplementation improved the growth performance of piglets, enhanced the metabolism of Gln, upregulated protein synthetic signaling in liver and skeletal muscle and decreased protein degradative signaling in muscle of piglets. Moreover, these effects of Ala-Gln were more effective than those of Ala+Gln.
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Fages A, Duarte-Salles T, Stepien M, Ferrari P, Fedirko V, Pontoizeau C, Trichopoulou A, Aleksandrova K, Tjønneland A, Olsen A, Clavel-Chapelon F, Boutron-Ruault MC, Severi G, Kaaks R, Kuhn T, Floegel A, Boeing H, Lagiou P, Bamia C, Trichopoulos D, Palli D, Pala V, Panico S, Tumino R, Vineis P, Bueno-de-Mesquita HB, Peeters PH, Weiderpass E, Agudo A, Molina-Montes E, Huerta JM, Ardanaz E, Dorronsoro M, Sjöberg K, Ohlsson B, Khaw KT, Wareham N, Travis RC, Schmidt JA, Cross A, Gunter M, Riboli E, Scalbert A, Romieu I, Elena-Herrmann B, Jenab M. Metabolomic profiles of hepatocellular carcinoma in a European prospective cohort. BMC Med 2015; 13:242. [PMID: 26399231 PMCID: PMC4581424 DOI: 10.1186/s12916-015-0462-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/25/2015] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Hepatocellular carcinoma (HCC), the most prevalent form of liver cancer, is difficult to diagnose and has limited treatment options with a low survival rate. Aside from a few key risk factors, such as hepatitis, high alcohol consumption, smoking, obesity, and diabetes, there is incomplete etiologic understanding of the disease and little progress in identification of early risk biomarkers. METHODS To address these aspects, an untargeted nuclear magnetic resonance metabolomic approach was applied to pre-diagnostic serum samples obtained from first incident, primary HCC cases (n = 114) and matched controls (n = 222) identified from amongst the participants of a large European prospective cohort. RESULTS A metabolic pattern associated with HCC risk comprised of perturbations in fatty acid oxidation and amino acid, lipid, and carbohydrate metabolism was observed. Sixteen metabolites of either endogenous or exogenous origin were found to be significantly associated with HCC risk. The influence of hepatitis infection and potential liver damage was assessed, and further analyses were made to distinguish patterns of early or later diagnosis. CONCLUSION Our results show clear metabolic alterations from early stages of HCC development with application for better etiologic understanding, prevention, and early detection of this increasingly common cancer.
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Affiliation(s)
- Anne Fages
- Institut des Sciences Analytiques, Centre de RMN à très hauts champs, CNRS/ENS Lyon/UCB Lyon-1, Université de Lyon, 5 rue de la Doua, 69100, Villeurbanne, France
| | | | - Magdalena Stepien
- International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | - Pietro Ferrari
- International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | - Veronika Fedirko
- Department of Epidemiology, Rollins School of Public Health, Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Clément Pontoizeau
- Institut des Sciences Analytiques, Centre de RMN à très hauts champs, CNRS/ENS Lyon/UCB Lyon-1, Université de Lyon, 5 rue de la Doua, 69100, Villeurbanne, France
| | - Antonia Trichopoulou
- Hellenic Health Foundation, Alexandroupoleos 23, GR-115 27, Athens, Greece
- Bureau of Epidemiologic Research, Academy of Athens, Kaisareias 13, GR-115 27, Athens, Greece
| | - Krasimira Aleksandrova
- Department of Epidemiology, German Institute of Human Nutrition (DIfE), Potsdam-Rehbrücke, Germany
| | - Anne Tjønneland
- Diet, Genes and Environment, Danish Cancer Society Research Center, Strandboulevarden 49, DK 2100, Copenhagen, Denmark
| | - Anja Olsen
- Diet, Genes and Environment, Danish Cancer Society Research Center, Strandboulevarden 49, DK 2100, Copenhagen, Denmark
| | - Françoise Clavel-Chapelon
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health Team, F-94805, Villejuif, France
- Université Paris Sud, UMRS 1018, F-94805, Villejuif, France
- Institut Gustave Roussy, F-94805, Villejuif, France
| | - Marie-Christine Boutron-Ruault
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Nutrition, Hormones and Women's Health Team, F-94805, Villejuif, France
- Université Paris Sud, UMRS 1018, F-94805, Villejuif, France
- Institut Gustave Roussy, F-94805, Villejuif, France
| | | | - Rudolf Kaaks
- Department of Cancer Epidemiology, German Cancer Research Centre, Heidelberg, Germany
| | - Tilman Kuhn
- Department of Cancer Epidemiology, German Cancer Research Centre, Heidelberg, Germany
| | - Anna Floegel
- Department of Epidemiology, German Institute of Human Nutrition (DIfE), Potsdam-Rehbrücke, Germany
| | - Heiner Boeing
- Department of Epidemiology, German Institute of Human Nutrition (DIfE), Potsdam-Rehbrücke, Germany
| | - Pagona Lagiou
- Department of Hygiene, Epidemiology, and Medical Statistics, University of Athens Medical School, 75 M. Asias, Goudi, GR-115 27, Athens, Greece
- Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
| | - Christina Bamia
- Department of Hygiene, Epidemiology, and Medical Statistics, University of Athens Medical School, 75 M. Asias, Goudi, GR-115 27, Athens, Greece
| | - Dimitrios Trichopoulos
- Hellenic Health Foundation, Alexandroupoleos 23, GR-115 27, Athens, Greece
- Bureau of Epidemiologic Research, Academy of Athens, Kaisareias 13, GR-115 27, Athens, Greece
- Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA, 02115, USA
| | - Domenico Palli
- Molecular and Nutritional Epidemiology Unit, Cancer Research and Prevention Institute - ISPO, Florence, Italy
| | - Valeria Pala
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Via Venezian 1, 20133, Milano, Italy
| | - Salvatore Panico
- Dipartimento di Medicina Clinica e Chirurgia, Federico II University, Naples, Italy
| | - Rosario Tumino
- Cancer Registry and Histopathology Unit, "Civic - M.P. Arezzo" Hospital, Ragusa, Italy
| | - Paolo Vineis
- Human Genetics Foundation (HuGeF), Torino, Italy
- MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK
| | - H Bas Bueno-de-Mesquita
- Department for Determinants of Chronic Diseases (DCD), National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Department of Gastroenterology and Hepatology, University Medical Centre, Utrecht, The Netherlands
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
- Department of Social & Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Petra H Peeters
- MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London, UK
- Department of Epidemiology, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Elisabete Weiderpass
- Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, Tromsø, Norway
- Department of Research, Cancer Registry of Norway, Oslo, Norway
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
- Samfundet Folkhälsan, Helsinki, Finland
| | - Antonio Agudo
- Unit of Nutrition and Cancer, IDIBELL, Catalan Institute of Oncology-ICO, L'Hospitalet de Llobregat, Barcelona, 08908, Spain
| | - Esther Molina-Montes
- Escuela Andaluza de Salud Pública, Instituto de Investigación Biosanitaria ibs.GRANADA, Hospitales Universitarios de Granada/Universidad de Granada, Granada, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - José María Huerta
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Department of Epidemiology, Murcia Regional Health Council, IMIB-Arrixaca, Murcia, Spain
| | - Eva Ardanaz
- CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
- Navarre Public Health Institute, Pamplona, Spain
| | - Miren Dorronsoro
- Public Health Direction and Biodonostia CIBERESP, Basque Regional Health Department, San Sebastian, Spain
| | - Klas Sjöberg
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Department of Gastroenterology and Nutrition, Skåne University Hospital, Malmö, Sweden
| | - Bodil Ohlsson
- Department of Clinical Sciences, Division of Internal Medicine, Skåne University Hospital, Lund University, Malmö, Sweden
| | - Kay-Tee Khaw
- University of Cambridge School of Clinical Medicine, Clinical Gerontology Unit, Addenbrooke's Hospital, Cambridge, UK
| | - Nick Wareham
- MRC Epidemiology Unit, University of Cambridge, Cambridge, UK
| | - Ruth C Travis
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Julie A Schmidt
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Amanda Cross
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
| | - Marc Gunter
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
| | - Elio Riboli
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London, UK
| | - Augustin Scalbert
- International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | - Isabelle Romieu
- International Agency for Research on Cancer (IARC-WHO), Lyon, France
| | - Benedicte Elena-Herrmann
- Institut des Sciences Analytiques, Centre de RMN à très hauts champs, CNRS/ENS Lyon/UCB Lyon-1, Université de Lyon, 5 rue de la Doua, 69100, Villeurbanne, France.
| | - Mazda Jenab
- International Agency for Research on Cancer (IARC-WHO), Lyon, France.
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Park HM, Shon JC, Lee MY, Liu KH, Kim JK, Lee SJ, Lee CH. Mass spectrometry-based metabolite profiling in the mouse liver following exposure to ultraviolet B radiation. PLoS One 2014; 9:e109479. [PMID: 25275468 PMCID: PMC4183543 DOI: 10.1371/journal.pone.0109479] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 08/31/2014] [Indexed: 01/07/2023] Open
Abstract
Although many studies have been performed on the effects of ultraviolet (UV) radiation on the skin, only a limited number of reports have investigated these effects on non-skin tissue. This study aimed to describe the metabolite changes in the liver of hairless mice following chronic exposure to UVB radiation. We did not observe significant macroscopic changes or alterations in hepatic cholesterol and triglyceride levels in the liver of UVB-irradiated mice, compared with those for normal mice. In this study, we detected hepatic metabolite changes by UVB exposure and identified several amino acids, fatty acids, nucleosides, carbohydrates, phospholipids, lysophospholipids, and taurine-conjugated cholic acids as candidate biomarkers in response to UVB radiation in the mouse liver by using various mass spectrometry (MS)-based metabolite profiling including ultra-performance liquid chromatography-quadrupole time-of-flight (TOF)-MS, gas chromatography-TOF-MS and nanomate LTQ-MS. Glutamine exhibited the most dramatic change with a 5-fold increase in quantity. The results from altering several types of metabolites suggest that chronic UVB irradiation may impact significantly on major hepatic metabolism processes, despite the fact that the liver is not directly exposed to UVB radiation. MS-based metabolomic approach for determining regulatory hepatic metabolites following UV irradiation will provide a better understanding of the relationship between internal organs and UV light.
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Affiliation(s)
- Hye Min Park
- Department of Bioscience and Biotechnology, Konkuk University, Gwangjin-gu, Seoul, Republic of Korea
| | - Jong Cheol Shon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Buk-gu, Daegu, Republic of Korea
| | - Mee Youn Lee
- Department of Bioscience and Biotechnology, Konkuk University, Gwangjin-gu, Seoul, Republic of Korea
| | - Kwang-Hyeon Liu
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Kyungpook National University, Buk-gu, Daegu, Republic of Korea
| | - Jeong Kee Kim
- Food Research Institute, AmorePacific Corporation R&D Center, Giheung-gu, Yongin, Gyeonggi-do, Republic of Korea
| | - Sang Jun Lee
- Food Research Institute, AmorePacific Corporation R&D Center, Giheung-gu, Yongin, Gyeonggi-do, Republic of Korea
| | - Choong Hwan Lee
- Department of Bioscience and Biotechnology, Konkuk University, Gwangjin-gu, Seoul, Republic of Korea
- * E-mail:
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Xu Q, Feng CY, Hori TS, Plouffe DA, Buchanan JT, Rise ML. Family-specific differences in growth rate and hepatic gene expression in juvenile triploid growth hormone (GH) transgenic Atlantic salmon (Salmo salar). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2013; 8:317-33. [PMID: 24145116 DOI: 10.1016/j.cbd.2013.09.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 09/24/2013] [Accepted: 09/26/2013] [Indexed: 01/13/2023]
Abstract
Growth hormone transgenic (GHTg) Atlantic salmon (Salmo salar) have enhanced growth when compared to their non-transgenic counterparts, and this trait can be beneficial for aquaculture production. Biological confinement of GHTg Atlantic salmon may be achieved through the induction of triploidy (3N). The growth rates of triploid GH transgenic (3NGHTg) Atlantic salmon juveniles were found to significantly vary between families in the AquaBounty breeding program. In order to characterize gene expression associated with enhanced growth in juvenile 3NGHTg Atlantic salmon, a functional genomics approach (32K cDNA microarray hybridizations followed by QPCR) was used to identify and validate liver transcripts that were differentially expressed between two fast-growing 3NGHTg Atlantic salmon families (AS11, AS26) and a slow-growing 3NGHTg Atlantic salmon family (AS25); juvenile growth rate was evaluated over a 45-day period. Of 687 microarray-identified differentially expressed features, 143 (116 more highly expressed in fast-growing and 27 more highly expressed in slow-growing juveniles) were identified in the AS11 vs. AS25 microarray study, while 544 (442 more highly expressed in fast-growing and 102 more highly expressed in slow-growing juveniles) were identified in the AS26 vs. AS25 microarray study. Forty microarray features (39 putatively associated with fast growth and 1 putatively associated with slow growth) were present in both microarray experiment gene lists. The expression levels of 15 microarray-identified transcripts were studied using QPCR with individual RNA samples to validate microarray results and to study biological variability of transcript expression. The QPCR results agreed with the microarray results for 12 of 13 putative fast-growth associated transcripts, but QPCR did not validate the microarray results for 2 putative slow-growth associated transcripts. Many of the 39 microarray-identified genes putatively associated at the transcript expression level with fast-growing 3NGHTg salmon juveniles (including APOA1, APOA4, B2M, FADSD6, FTM, and GAPDH) are involved in metabolism, iron homeostasis and oxygen transport, and immune- or stress-related responses. The results of this study increase our knowledge of family-specific impacts on growth rate and hepatic gene expression in juvenile 3NGHTg Atlantic salmon. In addition, this study provides a suite of putative rapid growth rate-associated transcripts that may contribute to the development of molecular markers [e.g. intronic, exonic or regulatory region single nucleotide polymorphisms (SNPs)] for the selection of GHTg Atlantic salmon broodstock that can be utilized to produce sterile triploids of desired growth performance for future commercial applications.
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Affiliation(s)
- Qingheng Xu
- Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL A1C 5S7, Canada
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Jourdan M, Deutz NEP, Cynober L, Aussel C. Consequences of age-related splanchnic sequestration of leucine on interorgan glutamine metabolism in old rats. J Appl Physiol (1985) 2013; 115:229-34. [DOI: 10.1152/japplphysiol.01230.2012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dietary leucine (Leu) serves as a nitrogen donor for de novo glutamine (Gln) synthesis in muscle. However, aging is characterized by an increase in the splanchnic extraction of Leu (SPELeu), i.e., splanchnic sequestration (SSLeu), which may affect muscle Gln metabolism and its subsequent homeostasis at the whole-body level. The aim of the work was to assess the effect of age-related SSLeu on Gln metabolism in the muscle, gut, liver, kidney, and Gln exchanges among these organs during fed conditions. Young-adult (3-mo-old) or aged (24-mo-old), male Sprague-Dawley rats were studied during fed condition [infusion of amino acids (AA) into the duodenum from time 0 min (T0) to T60] under anesthesia. L-[5-15N]Gln and L[1-13C]Leu were infused into the jugular vein and L-[5,5,5-2H3]Leu into the duodenum. At T60, blood samples were taken from carotid artery, portal vein, hepatic vein, renal vein, and inferior vena cava for tracer-tracee ratio and AA level measurements. SSLeu was observed in old rats and was negatively correlated with muscle Gln production ( r = −0.501, P < 0.01). In addition, reduced Gln muscle release in old rats was accompanied by reduced Gln uptake by the gut and kidney. However, net Gln balance across organs was not different between young adult and old rats. During fed conditions in old rats, muscle Gln production and release are reduced in relation to the observed, increased SPELeu and reduced renal and intestinal Gln uptake to maintain whole-body Gln homeostasis. Our results demonstrate the existence of an age-related change of interorgan Gln metabolism, which may be, in part, driven by SSLeu.
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Affiliation(s)
- Marion Jourdan
- Laboratory of Biological Nutrition, EA 4466, Paris Descartes University, Paris, France
| | | | - Luc Cynober
- Laboratory of Biological Nutrition, EA 4466, Paris Descartes University, Paris, France
- Clinical Chemistry, Cochin and Hotel-Dieu Hospital, Paris, France; and
| | - Christian Aussel
- Laboratory of Biological Nutrition, EA 4466, Paris Descartes University, Paris, France
- Nutrition Unit, Pharmacy, Henri-Mondor Hospital, Creteil, France
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Gebhardt R, Coffer PJ. Hepatic autophagy is differentially regulated in periportal and pericentral zones - a general mechanism relevant for other tissues? Cell Commun Signal 2013; 11:21. [PMID: 23531205 PMCID: PMC3623826 DOI: 10.1186/1478-811x-11-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 03/11/2013] [Indexed: 02/08/2023] Open
Abstract
Background Liver zonation, the fact that metabolic pathways are spatially separated along the liver sinusoids, is fundamental for proper functioning of this organ. For example, glutamine synthesis from glutamate and ammonia is localized pericentrally in only 7% of the hepatocytes concentrically arranged around the central veins. Recently, we found that FOXO transcription factors lead to upregulation of glutamine synthetase expression inducing autophagy via increasing glutamine production. Since in liver this mechanism can only be functioning in the pericentral zone it remains unclear how autophagy might be regulated in the rest of liver parenchyma. Presentation of the hypothesis We hypothesize that the regulation of autophagy by glutamine in liver is zonated. In the periportal zone, autophagy is inhibited by low intracellular glutamine but high essential amino acids, while in the pericentral zone it is stimulated by high intracellular glutamine. This zonation may be controlled by the Wnt and Hedgehog signalling pathways through reciprocal influence on the expression of amino acid transporters and metabolic enzymes in the different zones of the parenchyma. Testing the hypothesis The hypothesis can be tested in transgenic mice with conditional hepatocyte-specific modulation of Wnt and Hedgehog signalling. Isolated periportal and pericentral hepatocyte populations allow for determining the different activities of autophagy and its regulating mechanisms in different zones of the parenchyma. Implications of the hypothesis Zonation of the regulation of autophagy may allow adapting the extent of the proteolytic breakdown of proteins and organelles to different physiological needs in different zones of liver parenchyma. In this manner metabolic functions can be supported in one zone, for example maintenance of blood glucose levels during starvation which is a periportal issue, while simultaneously preventing cytotoxic events in the opposite zone. Likewise, lipid metabolism can be differentially influenced by uncoupling periportal lipophagy from pericentral breakdown of peroxisomes. Further implications concern the shaping of morphogen gradients along the sinusoidal axis by autophagy, and the different contribution of autophagy to the development of various different liver pathologies. The proposed dependence of the dual glutamine-dependent regulatory mechanisms of autophagy on inverse gradients of Wnt and hedgehog signalling may be relevant for other tissues in which GS is heterogeneously expressed.
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Affiliation(s)
- Rolf Gebhardt
- Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Leipzig, Germany.
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Benzoic acid and specific 2-oxo acids activate hepatic efflux of glutamate at OAT2. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:491-8. [DOI: 10.1016/j.bbamem.2012.08.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 08/23/2012] [Accepted: 08/28/2012] [Indexed: 11/17/2022]
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da Silva R, Levillain O, Brosnan JT, Araneda S, Brosnan ME. The effect of portacaval anastomosis on the expression of glutamine synthetase and ornithine aminotransferase in perivenous hepatocytes. Can J Physiol Pharmacol 2012; 91:362-8. [PMID: 23656379 DOI: 10.1139/cjpp-2012-0060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
There is functional zonation of metabolism across the liver acinus, with glutamine synthetase restricted to a narrow band of cells around the terminal hepatic venules. Portacaval anastomosis, where there is a major rerouting of portal blood flow from the portal vein directly to the vena cava bypassing the liver, has been reported to result in a marked decrease in the activity of glutamine synthetase. It is not known whether this represents a loss of perivenous hepatocytes or whether there is a specific loss of glutamine synthetase. To answer this question, we have determined the activity of glutamine synthetase and another enzyme from the perivenous compartment, ornithine aminotransferase, as well as the immunochemical localization of both glutamine synthetase and ornithine aminotransferase in rats with a portacaval shunt. The portacaval shunt caused a marked decrease in glutamine synthetase activity and an increase in ornithine aminotransferase activity. Immunohistochemical analysis showed that the glutamine synthetase and ornithine aminotransferase proteins maintained their location in the perivenous cells. These results indicate that there is no generalized loss of perivenous hepatocytes, but rather, there is a significant alteration in the expression of these proteins and hence metabolism in this cell population.
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Affiliation(s)
- Robin da Silva
- Memorial University of Newfoundland, Department of Biochemistry, St. John's, NL A1B 3X9, Canada
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Qi S, Tu Z, Ouyang X, Wang L, Peng W, Cai A, Dai Y. Comparison of the metabolic profiling of hepatitis B virus-infected cirrhosis and alcoholic cirrhosis patients by using (1) H NMR-based metabonomics. Hepatol Res 2012; 42:677-85. [PMID: 22404306 DOI: 10.1111/j.1872-034x.2011.00964.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
AIM The aims of the present study were to depict the serum metabolic characteristics of hepatitis B virus (HBV)-infected cirrhosis and alcoholic cirrhosis patients, and to find the specific serum biomarkers associated with the diseases. METHODS A pilot metabolic profiling study was conducted using three groups: HBV-infected cirrhosis patients (n = 21), alcoholic cirrhosis patients (n = 20) and healthy controls (n = 20). (1) H nuclear magnetic resonance (NMR)-based metabonomics was used to obtain the serum metabolic profiles of the samples. The acquired data were processed by multivariate principal component analysis (PCA) and orthogonal partial least-squares-discriminant analysis (OPLS-DA). The discriminatory metabolites between HBV-infected cirrhosis and alcoholic cirrhosis were further validated by classical biochemical assays. RESULTS The OPLS-DA model was capable of distinguishing between HBV-infected and alcoholic cirrhosis patients. Five metabolites, creatine, acetoacetate, isobutyrate, glutamine and glutamate, were identified as the most influential factors to compare HBV-infected cirrhosis and alcoholic cirrhosis. The validation tests showed that the changes of the five metabolites were well coincident with the results of NMR. CONCLUSION NMR spectra combined with pattern recognition analysis techniques may provide a new way to explore the pathogenesis of HBV-infected and alcoholic cirrhosis patients.
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Affiliation(s)
- Suwen Qi
- Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Chongqing Medical University, Chongqing The Second Clinical Medical College, Jinan University, Guangdong, China
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Sun YJ, Wang HP, Liang YJ, Yang L, Li W, Wu YJ. An NMR-based metabonomic investigation of the subacute effects of melamine in rats. J Proteome Res 2012; 11:2544-50. [PMID: 22401608 DOI: 10.1021/pr2012329] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The subacute toxic effects of 28 days of exposure to three dosages (250, 500, 1000 mg/kg/day) of melamine on Wistar rats were investigated using nuclear magnetic resonance spectra, histopathological examination, and biochemical analysis. Rats treated with melamine developed adverse health effects compared to the controls, including decrease in body weight and kidney damage. Blood biochemical analysis showed that the blood urea nitrogen and creatinine increased distinctly compared to the control group. Urinary metabonomic analysis indicated that melamine caused an increase in succinate and citrate. Serum metabonomic analysis showed that the lowest dose led to an increase in dimethylglycine, N-acetylglycoprotein (NAC), accompanied by a decrease in taurine and glucose. Rats treated with the highest dose developed high levels of serum choline and 3-hydroxybutyrate (3-HB) together with low lactate levels. Metabonomic analysis of liver tissue indicated that melamine caused an increase in NAC, choline, and creatine, accompanied by a decrease in lactate, trimethylamine-N-oxide, glutamate, and glucose. All three dosages resulted in an increase in glutamate, lactate, choline, glucose, and animo acids and a decrease in 3-HB and pyruvate in aqueous kidney extract. These results indicate that melamine not only caused renal disfunction but also disturbed the liver's glucose, protein, and nitrogen metabolism.
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Affiliation(s)
- Ying-Jian Sun
- Department of Veterinary Medicine and Animal Science, Beijing Agriculture College, Beijing 102206, PR China
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38
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Orman MA, Androulakis IP, Berthiaume F, Ierapetritou MG. Metabolic network analysis of perfused livers under fed and fasted states: incorporating thermodynamic and futile-cycle-associated regulatory constraints. J Theor Biol 2011; 293:101-10. [PMID: 22037644 DOI: 10.1016/j.jtbi.2011.10.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 07/28/2011] [Accepted: 10/14/2011] [Indexed: 10/16/2022]
Abstract
Isolated liver perfusion systems have been extensively used to characterize intrinsic metabolic changes in liver under various conditions, including systemic injury, hepatotoxin exposure, and warm ischemia. Most of these studies were performed utilizing fasted animals prior to perfusion so that a simplified metabolic network could be used in order to determine intracellular fluxes. However, fasting induced metabolic alterations might interfere with disease related changes. Therefore, there is a need to develop a "unified" metabolic flux analysis approach that could be similarly applied to both fed and fasted states. In this study we explored a methodology based on elementary mode analysis in order to determine intracellular fluxes and active pathways simultaneously. In order to decrease the solution space, thermodynamic constraints, and enzymatic regulatory properties for the formation of futile cycles were further considered in the model, resulting in a mixed integer quadratic programming problem. Given the published experimental observations describing the perfused livers under fed and fasted states, the proposed approach successfully determined that gluconeogenesis, glycogenolysis and fatty acid oxidation were active in both states. However, fasting increased the fluxes in gluconeogenic reactions whereas it decreased fluxes associated with glycogenolysis, TCA cycle, fatty acid oxidation and electron transport reactions. This analysis further identified that more pathways were found to be active in fed state while their weight values were relatively lower compared to fasted state. Glucose, lactate, glutamine, glutamate and ketone bodies were also found to be important external metabolites whose extracellular fluxes should be used in the hepatic metabolic network analysis. In conclusion, the mathematical formulation explored in this study is an attractive tool to analyze the metabolic network of perfused livers under various disease conditions. This approach could be simultaneously applied to both fasted and fed data sets.
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Affiliation(s)
- Mehmet A Orman
- Department of Chemical and Biochemical Engineering, Rutgers, State University of New Jersey, 98 Brett Road, Piscataway, NJ 08854, USA
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Karaca M, Frigerio F, Maechler P. From pancreatic islets to central nervous system, the importance of glutamate dehydrogenase for the control of energy homeostasis. Neurochem Int 2011; 59:510-7. [DOI: 10.1016/j.neuint.2011.03.024] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 03/21/2011] [Accepted: 03/23/2011] [Indexed: 11/25/2022]
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40
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Hägglund MGA, Sreedharan S, Nilsson VCO, Shaik JHA, Almkvist IM, Bäcklin S, Wrange Ö, Fredriksson R. Identification of SLC38A7 (SNAT7) protein as a glutamine transporter expressed in neurons. J Biol Chem 2011; 286:20500-11. [PMID: 21511949 PMCID: PMC3121473 DOI: 10.1074/jbc.m110.162404] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 04/15/2011] [Indexed: 12/16/2022] Open
Abstract
The SLC38 family of transporters has in total 11 members in humans and they encode amino acid transporters called sodium-coupled amino acid transporters (SNAT). To date, five SNATs have been characterized and functionally subdivided into systems A (SLC38A1, SLC38A2, and SLC38A4) and N (SLC38A3 and SLC38A5) showing the highest transport for glutamine and alanine. Here we present identification of a novel glutamine transporter encoded by the Slc38a7 gene, which we propose should be named SNAT7. This transporter has L-glutamine as the preferred substrate but also transports other amino acids with polar side chains, as well as L-histidine and L-alanine. The expression pattern and substrate profile for SLC38A7 shows highest similarity to the known system N transporters. Therefore, we propose that SLC38A7 is a novel member of this system. We used in situ hybridization and immunohistochemistry with a custom-made antibody to show that SLC38A7 is expressed in all neurons, but not in astrocytes, in the mouse brain. SLC38A7 is unique in being the first system N transporter expressed in GABAergic and also other neurons. The preferred substrate and axonal localization of SLC38A7 close to the synaptic cleft indicates that SLC38A7 could have an important function for the reuptake and recycling of glutamate.
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Affiliation(s)
- Maria G. A. Hägglund
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
| | - Smitha Sreedharan
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
| | - Victor C. O. Nilsson
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
| | - Jafar H. A. Shaik
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
| | - Ingrid M. Almkvist
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
| | - Sofi Bäcklin
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
| | - Örjan Wrange
- the Department of Cell and Molecular Biology, Karolinska Institute, 17177 Stockholm, Sweden
| | - Robert Fredriksson
- From the Department of Neuroscience, Functional Pharmacology, Uppsala University, 75124 Uppsala, Sweden and
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41
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Julio-Pieper M, Flor PJ, Dinan TG, Cryan JF. Exciting times beyond the brain: metabotropic glutamate receptors in peripheral and non-neural tissues. Pharmacol Rev 2011; 63:35-58. [PMID: 21228260 DOI: 10.1124/pr.110.004036] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Metabotropic glutamate (mGlu) receptors are G-protein-coupled receptors expressed primarily on neurons and glial cells, where they are located in the proximity of the synaptic cleft. In the central nervous system (CNS), mGlu receptors modulate the effects of l-glutamate neurotransmission in addition to that of a variety of other neurotransmitters. However, mGlu receptors also have a widespread distribution outside the CNS that has been somewhat neglected to date. Based on this expression, diverse roles of mGlu receptors have been suggested in a variety of processes in health and disease including controlling hormone production in the adrenal gland and pancreas, regulating mineralization in the developing cartilage, modulating lymphocyte cytokine production, directing the state of differentiation in embryonic stem cells, and modulating gastrointestinal secretory function. Understanding the role of mGlu receptors in the periphery will also provide a better insight into potential side effects of drugs currently being developed for neurological and psychiatric conditions. This review summarizes the new potential roles of mGlu receptors and raises the possibility of novel pharmacological targets for various disorders.
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Affiliation(s)
- Marcela Julio-Pieper
- Laboratory of Neurogastroenterology, Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland
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42
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Orman MA, Berthiaume F, Androulakis IP, Ierapetritou MG. Pathway analysis of liver metabolism under stressed condition. J Theor Biol 2010; 272:131-40. [PMID: 21163266 DOI: 10.1016/j.jtbi.2010.11.042] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Revised: 11/17/2010] [Accepted: 11/24/2010] [Indexed: 11/28/2022]
Abstract
Pathway analysis is a useful tool which reveals important metabolic network properties. However, the big challenge is to propose an objective function for estimating active pathways, which represent the actual state of network. In order to provide weight values for all possible pathways within the metabolic network, this study presents different approaches, considering the structural and physiological properties of the metabolic network, aiming at a unique decomposition of the flux vector into pathways. These methods were used to analyze the hepatic metabolism considering available data sets obtained from the perfused livers of fasted rats receiving burn injury. Utilizing unique decomposition techniques and different fluxes revealed that higher weights were always attributed to short pathways. Specific pathways, including pyruvate, glutamate and oxaloacetate pools, and urea production from arginine, were found to be important or essential in all methods and experimental conditions. Moreover the pathways, including serine production from glycine and conversion between acetoacetate and B-OH-butyrate, were assigned higher weights. Pathway analysis was also used to identify the main sources for the production of certain products in the hepatic metabolic network to gain a better understanding of the effects of burn injury on liver metabolism.
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Affiliation(s)
- Mehmet A Orman
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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Workenhe ST, Hori TS, Rise ML, Kibenge MJT, Kibenge FSB. Infectious salmon anaemia virus (ISAV) isolates induce distinct gene expression responses in the Atlantic salmon (Salmo salar) macrophage/dendritic-like cell line TO, assessed using genomic techniques. Mol Immunol 2009; 46:2955-74. [PMID: 19616850 DOI: 10.1016/j.molimm.2009.06.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2009] [Revised: 06/12/2009] [Accepted: 06/18/2009] [Indexed: 12/22/2022]
Abstract
Infectious salmon anaemia virus (ISAV) is a marine orthomyxovirus of significant interest not only as a cause of a fatal disease of farmed Atlantic salmon resulting in severe economic losses to the aquaculture industry, but also as the only poikilothermic orthomyxovirus. ISAV targets vascular endothelial cells and macrophages, and is known to influence the expression of both innate and adaptive immune response relevant genes. ISAV isolates from different geographic regions have been shown to vary considerably in their pathogenicity for Atlantic salmon. This study aimed to characterize the Atlantic salmon TO macrophage/dendritic-like cell responses to infection with a selection of ISAV isolates of different genotypes and pathogenicity phenotypes. The first TO infection trial used ISAV isolates NBISA01 and RPC/NB-04-085-1 of high and low pathogenicity, respectively, and global gene expression analyses were carried out using approximately 16,000 gene (16K) salmonid cDNA microarrays to compare RNA samples extracted from TO cells harvested 24 and 72h post-infection versus time-matched uninfected controls. Overall, the microarray experiment showed that RPC/NB-04-085-1-infected cells had a higher total number of reproducibly dysregulated genes (88 genes: the sum of genes greater than 2-fold up- or down-regulated in all four replicate microarrays of a given comparison) than the NBISA01-infected cells (10 genes) for the combined sampling points (i.e. 24 and 72h). This microarray experiment identified several salmon genes that were differentially regulated by NBISA01 and RPC/NB-04-085-1, and which may be useful as molecular biomarkers of ISAV infection. An initial quantitative reverse transcription-polymerase chain reaction (QRT-PCR) study involving 25 microarray-identified genes confirmed the differences in the level of dysregulation of host transcripts between the two ISAV isolates (i.e. NBISA01 and RPC/NB-04-085-1). A second TO infection trial was run using a selection of four clinical ISAV isolates (Norway-810/9/99, a high pathogenicity isolate of European genotype; RPC/NB-04-085-1, a low pathogenicity isolate of European genotype; NBISA01, a high pathogenicity isolate of North American genotype; and RPC/NB-01-0593-1, an intermediate pathogenicity isolate of North American genotype), and UV-inactivated RPC/NB-04-085-1, with sampling at 24, 36, 48, 72, 96, and 120h post-infection. The microarray-identified, QRT-PCR validated suite of 24 molecular biomarkers of response to ISAV were used in a second QRT-PCR experiment to assess the TO cell gene expression responses to the four ISAV isolates at all six time points in the infection. The QRT-PCR data showed that RPC/NB-04-085-1 caused the highest fold changes of most immune-relevant genes [such as interferon-inducible protein Gig1, Mx1 protein, interferon-induced protein with tetratricopeptide repeats 5, Radical S-adenosyl methionine domain-containing protein (viperin), and several genes involved in the ISGylation pathway], followed by Norway-810/9/99. NBISA01 and RPC/NB-01-0593-01 (both of North American genotype) showed low fold up-regulation of transcripts that were highly induced by RPC/NB-04-085-1 isolate. These findings show that ISAV isolates have strain-specific variations in their ability to induce immune response genes.
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Affiliation(s)
- Samuel T Workenhe
- Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, 550 University Avenue, Charlottetown, P.E.I., Canada C1A 4P3
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44
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Biochemical effects of gadolinium chloride in rats liver and kidney studied by 1H NMR metabolomics. J RARE EARTH 2009. [DOI: 10.1016/s1002-0721(08)60234-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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45
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Watford M. Glutamine metabolism and function in relation to proline synthesis and the safety of glutamine and proline supplementation. J Nutr 2008; 138:2003S-2007S. [PMID: 18806115 DOI: 10.1093/jn/138.10.2003s] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
At normal intakes, dietary glutamine and glutamate are metabolized by the small intestine and essentially all glutamine within the body is synthesized de novo through the action of glutamine synthetase. The major sites of net glutamine synthesis are skeletal muscle, lung, and adipose tissue and, under some conditions, the liver. In addition to the small intestine, where glutamine is the major respiratory fuel, other sites of net glutamine utilization include the cells of the immune system, the kidneys, and the liver. The intestine expresses pyrroline 5-carboxylate (P5C) synthase, which means that proline is an end product of intestinal glutamine catabolism. Proline can also be synthesized from ornithine and the exact contribution of the 2 pathways is not certain. Infusion of proline i.v. to increase circulating concentrations is associated with increased proline oxidation and decreased proline synthesis. In contrast, conditions of proline insufficiency, after feeding low-proline diets or in response to high rates of proline catabolism in burn patients, do not result in increased proline synthesis. Glutamine supplementation is widespread and up to 0.57-0.75 g.kg(-1).d(-1) is well tolerated. Similarly, the only study of proline supplementation, in which patients with gyrate atrophy were given 488 mg.kg(-1).d(-1), reported no deleterious side effects. In the absence of controlled trials, it is currently not possible to estimate a safe upper limit for either of these 2 amino acids.
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Affiliation(s)
- Malcolm Watford
- Department of Nutritional Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
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46
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Tissue specificity of mitochondrial glutamate pathways and the control of metabolic homeostasis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:965-72. [PMID: 18486589 DOI: 10.1016/j.bbabio.2008.04.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Revised: 04/11/2008] [Accepted: 04/22/2008] [Indexed: 11/24/2022]
Abstract
Glutamate is implicated in numerous metabolic and signalling functions that vary according to specific tissues. Glutamate metabolism is tightly controlled by activities of mitochondrial enzymes and transmembrane carriers, in particular glutamate dehydrogenase and mitochondrial glutamate carriers that have been identified in recent years. It is remarkable that, although glutamate-specific enzymes and transporters share similar properties in most tissues, their regulation varies greatly according to particular organs in order to achieve tissue specific functions. This is illustrated in this review when comparing glutamate handling in liver, brain, and pancreatic beta-cells. We describe the main cellular glutamate pathways and their specific functions in different tissues, ultimately contributing to the control of metabolic homeostasis at the organism level.
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47
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Rousseaux CG. A Review of Glutamate Receptors I: Current Understanding of Their Biology. J Toxicol Pathol 2008. [DOI: 10.1293/tox.21.25] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Colin G. Rousseaux
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa
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Wang Y, Watford M. Glutamine, insulin and glucocorticoids regulate glutamine synthetase expression in C2C12 myotubes, Hep G2 hepatoma cells and 3T3 L1 adipocytes. BIOCHIMICA ET BIOPHYSICA ACTA 2007; 1770:594-600. [PMID: 17197094 PMCID: PMC1850228 DOI: 10.1016/j.bbagen.2006.11.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2006] [Revised: 10/26/2006] [Accepted: 11/16/2006] [Indexed: 10/23/2022]
Abstract
The cell-specific regulation of glutamine synthetase expression was studied in three cell lines. In C2C12 myotubes, glucocorticoids increased the abundance of both glutamine synthetase protein and mRNA. Culture in the absence of glutamine also resulted in very high glutamine synthetase protein abundance but mRNA levels were unchanged. Glucocorticoids also increased the abundance of glutamine synthetase mRNA in Hep G2 hepatoma cells but this was not reflected in changes in protein abundance. Culture of Hep G2 cells without glutamine resulted in very high levels of protein, again with no change in mRNA abundance. Insulin was without effect in both C2C12 and Hep G2 cells. In 3T3 L1 adipocytes glucocorticoids increased the abundance of both glutamine synthetase mRNA and protein, insulin added alone had no effect but in the presence of glucocorticoids resulted in lower mRNA levels than seen with glucocorticoids alone, although protein levels remained high under such conditions. In contrast to the other cell lines glutamine synthetase protein levels were relatively unchanged by culture in the absence of glutamine. The results support the hypothesis that in myocytes, and hepatomas, but not in adipocytes, glutamine acts to moderate glutamine synthetase induction by glucocorticoids.
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Affiliation(s)
- Yanxin Wang
- Department of Nutritional Sciences, Thompson Hall, Cook College, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
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49
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Gebhardt R, Baldysiak-Figiel A, Krügel V, Ueberham E, Gaunitz F. Hepatocellular expression of glutamine synthetase: an indicator of morphogen actions as master regulators of zonation in adult liver. ACTA ACUST UNITED AC 2007; 41:201-66. [PMID: 17368308 DOI: 10.1016/j.proghi.2006.12.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Glutamine synthetase (GS) has long been known to be expressed exclusively in pericentral hepatocytes most proximal to the central veins of liver lobuli. This enzyme as well as its peculiar distribution complementary to the periportal compartment for ureogenesis plays an important role in nitrogen metabolism, particularly in homeostasis of blood levels of ammonium ions and glutamine. Despite this fact and intensive studies in vivo and in vitro, many aspects of the regulation of its activity on the protein and on the genetic level remained enigmatic. Recent experimental advances using transgenic mice and new analytic tools have revealed the fundamental role of morphogens such as wingless-type MMTV integration site family member signals (Wnt), beta-catenin, and adenomatous polyposis coli in the regulation of this particular enzyme. In addition, novel information concerning the structure of transcription factor binding sites within regulatory regions of the GS gene and their interactions with signalling pathways could be collected. In this review we focus on all aspects of the regulation of GS in the liver and demonstrate how the new findings have changed our view of the determinants of liver zonation. What appeared as a simple response of hepatocytes to blood-derived factors and local cellular interactions must now be perceived as a fundamental mechanism of adult tissue patterning by morphogens that were considered mainly as regulators of developmental processes. Though GS may be the most obvious indicator of morphogen action among many other targets, elucidation of the complex regulation of the expression of the GS gene could pave the road for a better understanding of the mechanisms involved in patterning of liver parenchyma. Based on current knowledge we propose a new concept of how morphogens, hormones and other factors may act in concert, in order to restrict gene expression to small subpopulations of one differentiated cell type, the hepatocyte, in different anatomical locations. Although many details of this regulatory network are still missing, and an era of exciting new discoveries is still about to come, it can already be envisioned that similar mechanisms may well be active in other organs contributing to the fine-tuning of organ-specific functions.
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Affiliation(s)
- Rolf Gebhardt
- Institut für Biochemie, Medizinische Fakultät, Universität Leipzig, Johannisallee 30, 04103 Leipzig, Germany.
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Richards DA, Silva MA, Murphy N, Wigmore SJ, Mirza DF. Extracellular amino acid levels in the human liver during transplantation: a microdialysis study from donor to recipient. Amino Acids 2007; 33:429-37. [PMID: 17235452 DOI: 10.1007/s00726-006-0480-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Accepted: 11/20/2006] [Indexed: 11/28/2022]
Abstract
Using microdialysis, we have monitored extracellular levels of amino acids and related amines in the human liver at three stages of the transplantation procedure: donor retrieval, back table preparation and during 48 h post-implantation. By comparing the ratio of mean levels at the donor and back table stages, with the ratio between early (2-6 h) and late (43-48 h) post-reperfusion, these amines were classified into one of three groups. In one group, back table levels were markedly higher than during the donor stage, with levels declining over time post-reperfusion. A second group had much lower levels in the back table than during the donor phase, and post-reperfusion levels were either stable or increased over time. Concentrations of amino acids in the final group remained relatively constant at all stages. This study illustrates the value of microdialysis in providing organ-specific metabolic data that may indicate specific mechanisms of poor graft function.
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Affiliation(s)
- D A Richards
- Department of Pharmacology, Medical School, University of Birmingham, Edgbaston, Birmingham, UK.
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