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Hessheimer AJ, Flores E, Vengohechea J, Fondevila C. Better liver transplant outcomes by donor interventions? Curr Opin Organ Transplant 2024:00075200-990000000-00123. [PMID: 38785132 DOI: 10.1097/mot.0000000000001153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
PURPOSE OF REVIEW Donor risk factors and events surrounding donation impact the quantity and quality of grafts generated to meet liver transplant waitlist demands. Donor interventions represent an opportunity to mitigate injury and risk factors within donors themselves. The purpose of this review is to describe issues to address among donation after brain death, donation after circulatory determination of death, and living donors directly, for the sake of optimizing relevant outcomes among donors and recipients. RECENT FINDINGS Studies on donor management practices and high-level evidence supporting specific interventions are scarce. Nonetheless, for donation after brain death (DBD), critical care principles are employed to correct cardiocirculatory compromise, impaired tissue oxygenation and perfusion, and neurohormonal deficits. As well, certain treatments as well as marginally prolonging duration of brain death among otherwise stable donors may help improve posttransplant outcomes. In donation after circulatory determination of death (DCD), interventions are performed to limit warm ischemia and reverse its adverse effects. Finally, dietary and exercise programs have improved donation outcomes for both standard as well as overweight living donor (LD) candidates, while minimally invasive surgical techniques may offer improved outcomes among LD themselves. SUMMARY Donor interventions represent means to improve liver transplant yield and outcomes of liver donors and grafts.
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Affiliation(s)
- Amelia J Hessheimer
- General & Digestive Surgery Service, Hospital Universitario La Paz, IdiPAZ, CIBERehd
| | - Eva Flores
- Transplant Coordination Unit, Hospital Universitario La Paz, Madrid, Spain
| | - Jordi Vengohechea
- General & Digestive Surgery Service, Hospital Universitario La Paz, IdiPAZ, CIBERehd
| | - Constantino Fondevila
- General & Digestive Surgery Service, Hospital Universitario La Paz, IdiPAZ, CIBERehd
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2
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Hessheimer AJ, Flores E, Fondevila C. No Evidence of Progressive Proinflammatory Cytokine Storm in Brain Dead Organ Donors: Should We Avoid the Rush to Flush? Transplantation 2024; 108:839-840. [PMID: 38192013 DOI: 10.1097/tp.0000000000004901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Affiliation(s)
- Amelia J Hessheimer
- General & Digestive Surgery Service, Hospital Universitario La Paz, IdiPAZ, CIBERehd, Madrid, Spain
| | - Eva Flores
- Transplant Coordination Unit, Hospital Universitario La Paz, Madrid, Spain
| | - Constantino Fondevila
- General & Digestive Surgery Service, Hospital Universitario La Paz, IdiPAZ, CIBERehd, Madrid, Spain
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Tao R, Guo W, Li T, Wang Y, Wang P. Intestinal microbiota dysbiosis and liver metabolomic changes during brain death. JOURNAL OF INTENSIVE MEDICINE 2023; 3:345-351. [PMID: 38028643 PMCID: PMC10658038 DOI: 10.1016/j.jointm.2023.02.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/17/2023] [Accepted: 02/25/2023] [Indexed: 12/01/2023]
Abstract
Background Whether a causative link exists between brain death (BD) and intestinal microbiota dysbiosis is unclear, and the distortion in liver metabolism associated with BD requires further exploration. Methods A rat model of BD was constructed and sustained for 9 h (BD group, n=6). The sham group (n=6) underwent the same procedures, but the catheter was inserted into the epidural space without ballooning. Intestinal contents and portal vein plasma were collected for microbiota sequencing and microbial metabolite detection. Liver tissue was resected to investigate metabolic alterations, and the results were compared with those of a sham group. Results α-diversity indexes showed that BD did not alter bacterial diversity. Microbiota dysbiosis occurred after 9 h of BD. At the family level, Peptostreptococcaceae and Bacteroidaceae were both decreased in the BD group. At the genus level, Romboutsia, Bacteroides, Erysipelotrichaceae_UCG_004, Faecalibacterium, and Barnesiella were enriched in the sham group, whereas Ruminococcaceae_UCG_007, Lachnospiraceae_ND3007_group, and Papillibacter were enriched in the BD group. Short-chain fatty acids, bile acids, and 132 other microbial metabolites remained unchanged in both the intestinal contents and portal vein plasma of the BD group. BD caused alterations in 65 metabolites in the liver, of which, carbohydrates, amino acids, and organic acids accounted for 64.6%. Additionally, 80.0% of the differential metabolites were decreased in the BD group livers. Galactose metabolism was the most significant metabolic pathway in the BD group. Conclusions BD resulted in microbiota dysbiosis in rats; however, this dysbiosis did not alter microbial metabolites. Deterioration in liver metabolic function during extended periods of BD may reflect a continuous worsening in energy deficiency.
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Affiliation(s)
- Ruolin Tao
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
- Henan Key Laboratory for Digestive Organ Transplantation, Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
| | - Wenzhi Guo
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
- Henan Key Laboratory for Digestive Organ Transplantation, Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
| | - Tao Li
- Department of Biliary Surgery, Nanyang Central Hospital, Nanyang 473009, Henan, China
| | - Yong Wang
- Henan Key Laboratory for Digestive Organ Transplantation, Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
- Department of Anesthesiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
| | - Panliang Wang
- Henan Key Laboratory for Digestive Organ Transplantation, Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
- Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
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Li Y, Nieuwenhuis LM, Keating BJ, Festen EA, de Meijer VE. The Impact of Donor and Recipient Genetic Variation on Outcomes After Solid Organ Transplantation: A Scoping Review and Future Perspectives. Transplantation 2022; 106:1548-1557. [PMID: 34974452 PMCID: PMC9311456 DOI: 10.1097/tp.0000000000004042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/16/2021] [Accepted: 11/25/2021] [Indexed: 11/25/2022]
Abstract
At the outset of solid organ transplantation, genetic variation between donors and recipients was recognized as a major player in mechanisms such as allograft tolerance and rejection. Genome-wide association studies have been very successful in identifying novel variant-trait associations, but have been difficult to perform in the field of solid organ transplantation due to complex covariates, era effects, and poor statistical power for detecting donor-recipient interactions. To overcome a lack of statistical power, consortia such as the International Genetics and Translational Research in Transplantation Network have been established. Studies have focused on the consequences of genetic dissimilarities between donors and recipients and have reported associations between polymorphisms in candidate genes or their regulatory regions with transplantation outcomes. However, knowledge on the exact influence of genetic variation is limited due to a lack of comprehensive characterization and harmonization of recipients' or donors' phenotypes and validation using an experimental approach. Causal research in genetics has evolved from agnostic discovery in genome-wide association studies to functional annotation and clarification of underlying molecular mechanisms in translational studies. In this overview, we summarize how the recent advances and progresses in the field of genetics and genomics have improved the understanding of outcomes after solid organ transplantation.
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Affiliation(s)
- Yanni Li
- Department of Gastroenterology and Hepatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Lianne M. Nieuwenhuis
- Department of Surgery, section of Hepatobiliary Surgery and Liver Transplantation, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Brendan J. Keating
- Department of Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Eleonora A.M. Festen
- Department of Gastroenterology and Hepatology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Vincent E. de Meijer
- Department of Surgery, section of Hepatobiliary Surgery and Liver Transplantation, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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5
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Bera KD, Shah A, English MR, Ploeg R. Outcome measures in solid organ donor management research: a systematic review. Br J Anaesth 2021; 127:745-759. [PMID: 34420684 DOI: 10.1016/j.bja.2021.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 06/24/2021] [Accepted: 07/14/2021] [Indexed: 12/15/2022] Open
Abstract
AIM We systematically reviewed published outcome measures across randomised controlled trials (RCTs) of donor management interventions. METHODS The systematic review was conducted in accordance with recommendations by the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We searched MEDLINE, Embase, CENTRAL, Web of Science, and trial databases from 1980 to February 2021 for RCTs of donor management interventions. RESULTS Twenty-two RCTs (n=3432 donors) were included in our analysis. Fourteen RCTs (63.6%) reported a primary outcome relating to a single organ only. Eight RCTs primarily focused on aspects of donor optimisation in critical care. Thyroid hormones and methylprednisolone were the most commonly evaluated interventions (five and four studies, respectively). Only two studies, focusing on single organs (e.g. kidney), evaluated outcomes relating to other organs. The majority of studies evaluated physiological or biomarker-related outcomes. No study evaluated recipient health-related quality of life. Only one study sought consent from potential organ recipients. CONCLUSIONS The majority of RCTs evaluating donor management interventions only assessed single-organ outcomes or effects on donor stability in critical care. There is a need for an evaluation of patient-centred recipient outcomes and standardisation and reporting of outcome measures for future donor management RCTs.
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Affiliation(s)
- Kasia D Bera
- Oxford Transplant Centre, Nuffield Department of Surgical Sciences, Churchill Hospital, Oxford, UK; Vascular Surgery Department, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
| | - Akshay Shah
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Adult Intensive Care Unit, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - M Rex English
- Oxford Medical School, University of Oxford, Oxford, UK
| | - Rutger Ploeg
- Oxford Transplant Centre, Nuffield Department of Surgical Sciences, Churchill Hospital, Oxford, UK
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6
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van Erp AC, Qi H, Jespersen NR, Hjortbak MV, Ottens PJ, Wiersema‐Buist J, Nørregaard R, Pedersen M, Laustsen C, Leuvenink HGD, Jespersen B. Organ-specific metabolic profiles of the liver and kidney during brain death and afterwards during normothermic machine perfusion of the kidney. Am J Transplant 2020; 20:2425-2436. [PMID: 32282984 PMCID: PMC7496945 DOI: 10.1111/ajt.15885] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 03/05/2020] [Accepted: 03/05/2020] [Indexed: 02/06/2023]
Abstract
We investigated metabolic changes during brain death (BD) using hyperpolarized magnetic resonance (MR) spectroscopy and ex vivo graft glucose metabolism during normothermic isolated perfused kidney (IPK) machine perfusion. BD was induced in mechanically ventilated rats by inflation of an epidurally placed catheter; sham-operated rats served as controls. Hyperpolarized [1-13 C]pyruvate MR spectroscopy was performed to quantify pyruvate metabolism in the liver and kidneys at 3 time points during BD, preceded by injecting hyperpolarized[1-13 C]pyruvate. Following BD, glucose oxidation was measured using tritium-labeled glucose (d-6-3H-glucose) during IPK reperfusion. Quantitative polymerase chain reaction and biochemistry were performed on tissue/plasma. Immediately following BD induction, lactate increased in both organs (liver: eµd 0.21, 95% confidence interval [CI] [-0.27, -0.15]; kidney: eµd 0.26, 95% CI [-0.40, -0.12]. After 4 hours of BD, alanine production decreased in the kidney (eµd 0.14, 95% CI [0.03, 0.25], P < .05). Hepatic lactate and alanine profiles were significantly different throughout the experiment between groups (P < .01). During IPK perfusion, renal glucose oxidation was reduced following BD vs sham animals (eµd 0.012, 95% CI [0.004, 0.03], P < .001). No differences in enzyme activities were found. Renal gene expression of lactate-transporter MCT4 increased following BD (P < .01). In conclusion, metabolic processes during BD can be visualized in vivo using hyperpolarized magnetic resonance imaging and with glucose oxidation during ex vivo renal machine perfusion. These techniques can detect differences in the metabolic profiles of the liver and kidney following BD.
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Affiliation(s)
- Anne C. van Erp
- University of GroningenUniversity Medical Center GroningenDepartment of surgeryGroningenthe Netherlands
| | - Haiyun Qi
- MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | | | | | - Petra J. Ottens
- University of GroningenUniversity Medical Center GroningenDepartment of surgeryGroningenthe Netherlands
| | - Janneke Wiersema‐Buist
- University of GroningenUniversity Medical Center GroningenDepartment of surgeryGroningenthe Netherlands
| | | | | | - Christoffer Laustsen
- MR Research Center, Department of Clinical MedicineAarhus UniversityAarhusDenmark
| | - Henri G. D. Leuvenink
- University of GroningenUniversity Medical Center GroningenDepartment of surgeryGroningenthe Netherlands
| | - Bente Jespersen
- Department of Clinical MedicineAarhus UniversityAarhusDenmark,Department of Renal MedicineAarhus University HospitalAarhusDenmark
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7
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Abstract
Although kidney oxygen tensions are heterogenous, and mostly below renal vein level, the nephron is highly dependent on aerobic metabolism for active tubular transport. This renders the kidney particularly susceptible to hypoxia, which is considered a main characteristic and driver of acute and chronic kidney injury, albeit the evidence supporting this assumption is not entirely conclusive. Kidney transplants are exposed to several conditions that may interfere with the balance between oxygen supply and consumption, and enhance hypoxia and hypoxic injury. These include conditions leading to and resulting from brain death of kidney donors, ischemia and reperfusion during organ donation, storage and transplantation, postoperative vascular complications, vasoconstriction induced by immunosuppression, and impaired perfusion resulting from interstitial edema, inflammation, and fibrosis. Acute graft injury, the immediate consequence of hypoxia and reperfusion, results in delayed graft function and increased risk of chronic graft failure. Although current strategies to alleviate hypoxic/ischemic graft injury focus on limiting injury (eg, by reducing cold and warm ischemia times), experimental evidence suggests that preconditioning through local or remote ischemia, or activation of the hypoxia-inducible factor pathway, can decrease hypoxic injury. In combination with ex vivo machine perfusion such approaches hold significant promise for improving transplantation outcomes.
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Affiliation(s)
- Christian Rosenberger
- Department of Nephrology and Medical Intensive Care, Charité Universitaetsmedizin Berlin, Berlin, Germany.
| | - Kai-Uwe Eckardt
- Department of Nephrology and Medical Intensive Care, Charité Universitaetsmedizin Berlin, Berlin, Germany
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8
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Bera KD, Shah A, English MR, Harvey D, Ploeg RJ. Optimisation of the organ donor and effects on transplanted organs: a narrative review on current practice and future directions. Anaesthesia 2020; 75:1191-1204. [PMID: 32430910 DOI: 10.1111/anae.15037] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2020] [Indexed: 12/16/2022]
Abstract
Mortality remains high for patients on the waiting list for organ transplantation. A marked imbalance between the number of available organs and recipients that need to be transplanted persists. Organs from deceased donors are often declined due to perceived and actual suboptimal quality. Adequate donor management offers an opportunity to reduce organ injury and maximise the number of organs than can be offered in order to respect the donor's altruistic gift. The cornerstones of management include: correction of hypovolaemia; maintenance of organ perfusion; prompt treatment of diabetes insipidus; corticosteroid therapy; and lung protective ventilation. The interventions used to deliver these goals are largely based on pathophysiological rationale or extrapolations from general critical care patients. There is currently insufficient high-quality evidence that has assessed whether any interventions in the donor after brain death may actually improve immediate post-transplant function and long-term graft survival or recipient survival after transplantation. Improvements in our understanding of the underlying mechanisms following brain death, in particular the role of immunological and metabolic changes in donors, offer promising future therapeutic opportunities to increase organ utilisation. Establishing a UK donor management research programme involves consideration of ethical, logistical and legal issues that will benefit transplanted patients while respecting the wishes of donors and their families.
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Affiliation(s)
- K D Bera
- Oxford Biomedical Research Centre and Oxford University Hospital NHS Foundation Trust, John Radcliffe Hospital, Oxford, UK
| | - A Shah
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK.,Nuffield Department of Anaesthesia, John Radcliffe Hospital, Oxford, UK
| | - M R English
- University of Oxford Medical School, Oxford, UK
| | - D Harvey
- Department of Intensive Care Medicine, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - R J Ploeg
- Nuffield Department of Surgical Sciences and Oxford Biomedical Research Centre, University of Oxford, UK
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9
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Organ-specific responses during brain death: increased aerobic metabolism in the liver and anaerobic metabolism with decreased perfusion in the kidneys. Sci Rep 2018. [PMID: 29535334 PMCID: PMC5849719 DOI: 10.1038/s41598-018-22689-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Hepatic and renal energy status prior to transplantation correlates with graft survival. However, effects of brain death (BD) on organ-specific energy status are largely unknown. We studied metabolism, perfusion, oxygen consumption, and mitochondrial function in the liver and kidneys following BD. BD was induced in mechanically-ventilated rats, inflating an epidurally-placed Fogarty-catheter, with sham-operated rats as controls. A 9.4T-preclinical MRI system measured hourly oxygen availability (BOLD-related R2*) and perfusion (T1-weighted). After 4 hrs, tissue was collected, mitochondria isolated and assessed with high-resolution respirometry. Quantitative proteomics, qPCR, and biochemistry was performed on stored tissue/plasma. Following BD, the liver increased glycolytic gene expression (Pfk-1) with decreased glycogen stores, while the kidneys increased anaerobic- (Ldha) and decreased gluconeogenic-related gene expression (Pck-1). Hepatic oxygen consumption increased, while renal perfusion decreased. ATP levels dropped in both organs while mitochondrial respiration and complex I/ATP synthase activity were unaffected. In conclusion, the liver responds to increased metabolic demands during BD, enhancing aerobic metabolism with functional mitochondria. The kidneys shift towards anaerobic energy production while renal perfusion decreases. Our findings highlight the need for an organ-specific approach to assess and optimise graft quality prior to transplantation, to optimise hepatic metabolic conditions and improve renal perfusion while supporting cellular detoxification.
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10
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The Crosstalk between ROS and Autophagy in the Field of Transplantation Medicine. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:7120962. [PMID: 29410735 PMCID: PMC5749284 DOI: 10.1155/2017/7120962] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/21/2017] [Accepted: 10/08/2017] [Indexed: 12/17/2022]
Abstract
Many factors during the transplantation process influence posttransplant graft function and survival, including donor type and age, graft preservation methods (cold storage, machine perfusion), and ischemia-reperfusion injury. Successively, they will lead to cellular and molecular alterations that determine cell and ultimately organ fate. Oxidative stress and autophagy are implicated in posttransplant outcome since they are both affected by the stress responses triggered in each step (donor, preservation, and recipient) of the transplantation process. Furthermore, oxidative stress influences autophagy and vice versa. Interestingly, both processes have positive as well as negative effects on graft outcome, suggesting they are tightly linked during the transplantation process. In this review, we discuss the importance, regulation and crosstalk of oxidative signals, and autophagy in the field of transplantation medicine.
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11
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Abstract
Ever since the discovery of the major histocompatibility complex, scientific and clinical understanding in the field of transplantation has been advanced through genetic and genomic studies. Candidate-gene approaches and recent genome-wide association studies (GWAS) have enabled a deeper understanding of the complex interplay of the donor-recipient interactions that lead to transplant tolerance or rejection. Genetic analysis in transplantation, when linked to demographic and clinical outcomes, has the potential to drive personalized medicine by enabling individualized risk stratification and immunosuppression through the identification of variants associated with immune-mediated complications, post-transplant disease or alterations in drug-metabolizing genes.
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Affiliation(s)
- Joshua Y C Yang
- Division of Transplant Surgery, University of California San Francisco, 513 Parnassus Avenue, San Francisco, California 94143, USA
| | - Minnie M Sarwal
- Division of Transplant Surgery, University of California San Francisco, 513 Parnassus Avenue, San Francisco, California 94143, USA
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12
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Yu Z, Huang H, Reim A, Charles PD, Northage A, Jackson D, Parry I, Kessler BM. Optimizing 2D gas chromatography mass spectrometry for robust tissue, serum and urine metabolite profiling. Talanta 2017; 165:685-691. [PMID: 28153317 PMCID: PMC5294743 DOI: 10.1016/j.talanta.2017.01.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 12/31/2022]
Abstract
Two-dimensional gas chromatography mass spectrometry (GCxGC-MS) is utilized to an increasing extent in biomedical metabolomics. Here, we established and adapted metabolite extraction and derivatization protocols for cell/tissue biopsy, serum and urine samples according to their individual properties. GCxGC-MS analysis revealed detection of ~600 molecular features from which 165 were characterized representing different classes such as amino acids, fatty acids, lipids, carbohydrates, nucleotides and small polar components of glycolysis and the Krebs cycle using electron impact (EI) spectrum matching and validation using external standard compounds. Advantages of two-dimensional gas chromatography based resolution were demonstrated by optimizing gradient length and separation through modulation between the first and second column, leading to a marked increase in metabolite identification due to improved separation as exemplified for lactate versus pyruvate, talopyranose versus methyl palmitate and inosine versus docosahexaenoic acid. Our results demonstrate that GCxGC-MS represents a robust metabolomics platform for discovery and targeted studies that can be used with samples derived from the clinic. GCxGC-MS detected ~600 features;165 represented metabolites of different classes. Optimizing gradient length and separation through modulation improved metabolite ID. improved separation of lactate/pyruvate, talopyranose/palmitate and inosine/docosahexaenoate.
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Affiliation(s)
- Zhanru Yu
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Honglei Huang
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Alexander Reim
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Philip D Charles
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK
| | - Alan Northage
- Shimadzu UK Limited, Mill Court, Featherstone Road Wolverton, Mill South, Milton Keynes MK12 5RD, UK
| | - Dianne Jackson
- Shimadzu UK Limited, Mill Court, Featherstone Road Wolverton, Mill South, Milton Keynes MK12 5RD, UK
| | - Ian Parry
- Shimadzu UK Limited, Mill Court, Featherstone Road Wolverton, Mill South, Milton Keynes MK12 5RD, UK
| | - Benedikt M Kessler
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford OX3 7FZ, UK.
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