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Vankrunkelsven W, Thiessen S, Derde S, Vervoort E, Derese I, Pintelon I, Matheussen H, Jans A, Goossens C, Langouche L, Van den Berghe G, Vanhorebeek I. Development of muscle weakness in a mouse model of critical illness: does fibroblast growth factor 21 play a role? Skelet Muscle 2023; 13:12. [PMID: 37537627 PMCID: PMC10401744 DOI: 10.1186/s13395-023-00320-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 06/09/2023] [Indexed: 08/05/2023] Open
Abstract
BACKGROUND Critical illness is hallmarked by severe stress and organ damage. Fibroblast growth factor 21 (FGF21) has been shown to rise during critical illness. FGF21 is a pleiotropic hormone that mediates adaptive responses to tissue injury and repair in various chronic pathological conditions. Animal studies have suggested that the critical illness-induced rise in FGF21 may to a certain extent protect against acute lung, liver, kidney and brain injury. However, FGF21 has also been shown to mediate fasting-induced loss of muscle mass and force. Such loss of muscle mass and force is a frequent problem of critically ill patients, associated with adverse outcome. In the present study, we therefore investigated whether the critical illness-induced acute rise in FGF21 is muscle-protective or rather contributes to the pathophysiology of critical illness-induced muscle weakness. METHODS In a catheterised mouse model of critical illness induced by surgery and sepsis, we first assessed the effects of genetic FGF21 inactivation, and hence the inability to acutely increase FGF21, on survival, body weight, muscle wasting and weakness, and markers of muscle cellular stress and dysfunction in acute (30 h) and prolonged (5 days) critical illness. Secondly, we assessed whether any effects were mirrored by supplementing an FGF21 analogue (LY2405319) in prolonged critical illness. RESULTS FGF21 was not required for survival of sepsis. Genetic FGF21 inactivation aggravated the critical illness-induced body weight loss (p = 0.0003), loss of muscle force (p = 0.03) and shift to smaller myofibers. This was accompanied by a more pronounced rise in markers of endoplasmic reticulum stress in muscle, without effects on impairments in mitochondrial respiratory chain enzyme activities or autophagy activation. Supplementing critically ill mice with LY2405319 did not affect survival, muscle force or weight, or markers of muscle cellular stress/dysfunction. CONCLUSIONS Endogenous FGF21 is not required for sepsis survival, but may partially protect muscle force and may reduce cellular stress in muscle. Exogenous FGF21 supplementation failed to improve muscle force or cellular stress, not supporting the clinical applicability of FGF21 supplementation to protect against muscle weakness during critical illness.
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Affiliation(s)
- Wouter Vankrunkelsven
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Steven Thiessen
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Sarah Derde
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Ellen Vervoort
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Inge Derese
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Isabel Pintelon
- Laboratory of Cell Biology and Histology, University of Antwerp, Antwerp, Belgium
| | - Hanne Matheussen
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Alexander Jans
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Chloë Goossens
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium
| | - Ilse Vanhorebeek
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, B-3000, Leuven, Belgium.
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Vankrunkelsven W, Derde S, Gunst J, Vander Perre S, Declerck E, Pauwels L, Derese I, Van den Berghe G, Langouche L. Obesity attenuates inflammation, protein catabolism, dyslipidaemia, and muscle weakness during sepsis, independent of leptin. J Cachexia Sarcopenia Muscle 2022; 13:418-433. [PMID: 34994068 PMCID: PMC8818596 DOI: 10.1002/jcsm.12904] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 11/23/2021] [Accepted: 11/29/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Muscle weakness is a frequently occurring complication of sepsis, associated with increased morbidity and mortality. Interestingly, obesity attenuates sepsis-induced muscle wasting and weakness. As the adipokine leptin is strongly elevated in obesity and has been shown to affect muscle homeostasis in non-septic conditions, we aimed to investigate whether leptin mediates the protective effect of obesity on sepsis-induced muscle weakness. METHODS In a mouse model of sepsis, we investigated the effects of genetic leptin inactivation in obese mice (leptin-deficient obese mice vs. diet-induced obese mice) and of leptin supplementation in lean mice (n = 110). We assessed impact on survival, body weight and composition, markers of muscle wasting and weakness, inflammation, and lipid metabolism. In human lean and overweight/obese intensive care unit (ICU) patients, we assessed markers of protein catabolism (n = 1388) and serum leptin (n = 150). RESULTS Sepsis mortality was highest in leptin-deficient obese mice (53% vs. 23% in diet-induced obese mice and 37% in lean mice, P = 0.03). Irrespective of leptin, after 5 days of sepsis, lean mice lost double the amount of lean body mass than obese mice (P < 0.0005). Also, irrespective of leptin, obese mice maintained specific muscle force up to healthy levels (P = 0.3) whereas lean mice suffered from reduced specific muscle force (72% of healthy controls, P < 0.0002). As compared with lean septic mice, both obese septic groups had less muscle atrophy, liver amino acid catabolism, and inflammation with a 50% lower plasma TNFα increase (P < 0.005). Conversely, again mainly irrespective of leptin, obese mice lost double amount of fat mass than lean mice after 5 days of sepsis (P < 0.0001), showed signs of increased lipolysis and ketogenesis, and had higher plasma HDL and LDL lipoprotein concentrations (P ≤ 0.01 for all). Muscle fibre type composition was not altered during sepsis, but a higher atrophy sensitivity of type IIb fibres compared with IIa and IIx fibres was observed, independent of obesity or leptin. After 5 days of critical illness, serum leptin was higher (P < 0.0001) and the net waste of nitrogen (P = 0.006) and plasma urea-to-creatinine ratio (P < 0.0001) was lower in overweight/obese compared with lean ICU human patients. CONCLUSIONS Leptin did not mediate the protective effect of obesity against sepsis-induced muscle wasting and weakness in mice. Instead, obesity-independent of leptin-attenuated inflammation, protein catabolism, and dyslipidaemia, pathways that may play a role in the observed muscle protection.
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Affiliation(s)
- Wouter Vankrunkelsven
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Sarah Derde
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Jan Gunst
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Sarah Vander Perre
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Emiel Declerck
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Lies Pauwels
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Inge Derese
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Lies Langouche
- Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
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Vankrunkelsven W, Gunst J, Amrein K, Bear DE, Berger MM, Christopher KB, Fuhrmann V, Hiesmayr M, Ichai C, Jakob SM, Lasocki S, Montejo JC, Oudemans-van Straeten HM, Preiser JC, Blaser AR, Rousseau AF, Singer P, Starkopf J, van Zanten AR, Weber-Carstens S, Wernerman J, Wilmer A, Casaer MP. Monitoring and parenteral administration of micronutrients, phosphate and magnesium in critically ill patients: The VITA-TRACE survey. Clin Nutr 2020; 40:590-599. [PMID: 32624243 DOI: 10.1016/j.clnu.2020.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/29/2020] [Accepted: 06/07/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Despite the presumed importance of preventing and treating micronutrient and mineral deficiencies, it is still not clear how to optimize measurement and administration in critically ill patients. In order to design future comparative trials aimed at optimizing micronutrient and mineral management, an important first step is to gain insight in the current practice of micronutrient, phosphate and magnesium monitoring and administration. METHODS Within the metabolism-endocrinology-nutrition (MEN) section of the European Society of Intensive Care Medicine (ESICM), the micronutrient working group designed a survey addressing current practice in parenteral micronutrient and mineral administration and monitoring. Invitations were sent by the ESICM research department to all ESICM members and past members. RESULTS Three hundred thirty-four respondents completed the survey, predominantly consisting of physicians (321 [96.1%]) and participants working in Europe (262 [78.4%]). Eighty-one (24.3%) respondents reported to monitor micronutrient deficiencies through clinical signs and/or laboratory abnormalities, and 148 (44.3%) reportedly measure blood micronutrient concentrations on a routine basis. Two hundred ninety-two (87.4%) participants provided specific data on parenteral micronutrient supplementation, of whom 150 (51.4%) reported early administration of combined multivitamin and trace element preparations at least in selected patients. Among specific parenteral micronutrient preparations, thiamine (146 [50.0%]) was reported to be the most frequently administered micronutrient, followed by vitamin B complex (104 [35.6%]) and folic acid (86 [29.5%]). One hundred twenty (35.9%) and 113 (33.8%) participants reported to perform daily measurements of phosphate and magnesium, respectively, whereas 173 (59.2%) and 185 (63.4%) reported to routinely supplement these minerals parenterally. CONCLUSION The survey revealed a wide variation in current practices of micronutrient, phosphate and magnesium measurement and parenteral administration, suggesting a risk of insufficient prevention, diagnosis and treatment of deficiencies. These results provide the context for future comparative studies, and identify areas for knowledge translation and recommendations.
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Affiliation(s)
- Wouter Vankrunkelsven
- KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Intensive Care Medicine, Leuven, Belgium
| | - Jan Gunst
- KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Intensive Care Medicine, Leuven, Belgium
| | - Karin Amrein
- Medical University of Graz, Division of Endocrinology and Diabetology, Department of Internal Medicine, Graz, Austria
| | - Danielle E Bear
- Guy´s and St Thomas' NHS Foundation Trust, Department of Critical Care and Department of Nutrition and Dietetics, London, United Kingdom
| | - Mette M Berger
- University of Lausanne Hospital - CHUV, Service of Intensive Care Medicine & Burns, Lausanne, Switzerland
| | | | - Valentin Fuhrmann
- University Medical Center Hamburg-Eppendorf, Department for Intensive Care Medicine, Hamburg, Germany
| | - Michael Hiesmayr
- Klinische Abteilung für Herz-Thorax-Gefäßchirurgische Anästhesie & Intensivmedizin, Medizinische Universität Wien, Vienna, Austria
| | - Carole Ichai
- University Côte d´Azur, CHU de Nice, Hôpital Pasteur 2, Department of Anesthesiology and Critical Care Medicine, Nice, France
| | - Stephan M Jakob
- Inselspital, Bern University Hospital, University of Bern, Department of Intensive Care Medicine, Bern, Switzerland
| | - Sigismond Lasocki
- Centre hospitalier universitaire d´Angers, Département Anesthésie-Réanimation, Angers, France
| | - Juan C Montejo
- Hospital Universitario 12 de Octubre, Intensive Care Medicine Department, Madrid, Spain
| | | | - Jean-Charles Preiser
- Erasme University Hospital - Université Libre de Bruxelles, Department of Intensive Care, Brussels, Belgium
| | - Annika Reintam Blaser
- Lucerne Cantonal Hospital, Department of Intensive Care Medicine, Lucerne, Switzerland; University of Tartu, Department of Anaesthesiology and Intensive Care, Tartu, Estonia
| | | | - Pierre Singer
- Rabin Medical Center, Tel Aviv University, General Intensive Care Department and Institute for Nutrition Research, Tel Aviv, Israel
| | - Joel Starkopf
- University of Tartu - Tartu University Hospital, Department of Anaesthesiology and Intensive Care, Tartu, Estonia
| | | | - Steffen Weber-Carstens
- Charité - Universitätsmedizin Berlin, Department of Anesthesiology and Operative Intensive Care Medicine, Berlin, Germany
| | - Jan Wernerman
- Karolinska University Hospital Huddinge - Karolinska Institutet, Intensive Care Medicine, Stockholm, Sweden
| | | | - Michael P Casaer
- KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Intensive Care Medicine, Leuven, Belgium.
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Dubois V, Gheeraert C, Vankrunkelsven W, Dubois‐Chevalier J, Dehondt H, Bobowski‐Gerard M, Vinod M, Zummo FP, Güiza F, Ploton M, Dorchies E, Pineau L, Boulinguiez A, Vallez E, Woitrain E, Baugé E, Lalloyer F, Duhem C, Rabhi N, van Kesteren RE, Chiang C, Lancel S, Duez H, Annicotte J, Paumelle R, Vanhorebeek I, Van den Berghe G, Staels B, Lefebvre P, Eeckhoute J. Endoplasmic reticulum stress actively suppresses hepatic molecular identity in damaged liver. Mol Syst Biol 2020; 16:e9156. [PMID: 32407006 PMCID: PMC7224309 DOI: 10.15252/msb.20199156] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 04/09/2020] [Accepted: 04/14/2020] [Indexed: 02/06/2023] Open
Abstract
Liver injury triggers adaptive remodeling of the hepatic transcriptome for repair/regeneration. We demonstrate that this involves particularly profound transcriptomic alterations where acute induction of genes involved in handling of endoplasmic reticulum stress (ERS) is accompanied by partial hepatic dedifferentiation. Importantly, widespread hepatic gene downregulation could not simply be ascribed to cofactor squelching secondary to ERS gene induction, but rather involves a combination of active repressive mechanisms. ERS acts through inhibition of the liver-identity (LIVER-ID) transcription factor (TF) network, initiated by rapid LIVER-ID TF protein loss. In addition, induction of the transcriptional repressor NFIL3 further contributes to LIVER-ID gene repression. Alteration to the liver TF repertoire translates into compromised activity of regulatory regions characterized by the densest co-recruitment of LIVER-ID TFs and decommissioning of BRD4 super-enhancers driving hepatic identity. While transient repression of the hepatic molecular identity is an intrinsic part of liver repair, sustained disequilibrium between the ERS and LIVER-ID transcriptional programs is linked to liver dysfunction as shown using mouse models of acute liver injury and livers from deceased human septic patients.
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Affiliation(s)
- Vanessa Dubois
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
- Present address:
Clinical and Experimental EndocrinologyDepartment of Chronic Diseases, Metabolism and Ageing (CHROMETA)KU LeuvenLeuvenBelgium
| | - Céline Gheeraert
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Wouter Vankrunkelsven
- Clinical Division and Laboratory of Intensive Care MedicineDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | | | - Hélène Dehondt
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | | | - Manjula Vinod
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | | | - Fabian Güiza
- Clinical Division and Laboratory of Intensive Care MedicineDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Maheul Ploton
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Emilie Dorchies
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Laurent Pineau
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Alexis Boulinguiez
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Emmanuelle Vallez
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Eloise Woitrain
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Eric Baugé
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Fanny Lalloyer
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Christian Duhem
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Nabil Rabhi
- UMR 8199 ‐ EGIDCNRSInstitut Pasteur de LilleUniversity of LilleLilleFrance
| | - Ronald E van Kesteren
- Center for Neurogenomics and Cognitive ResearchNeuroscience Campus AmsterdamVU UniversityAmsterdamThe Netherlands
| | - Cheng‐Ming Chiang
- Simmons Comprehensive Cancer CenterDepartments of Biochemistry and PharmacologyUniversity of Texas Southwestern Medical CenterDallasTXUSA
| | - Steve Lancel
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Hélène Duez
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | | | - Réjane Paumelle
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Ilse Vanhorebeek
- Clinical Division and Laboratory of Intensive Care MedicineDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Greet Van den Berghe
- Clinical Division and Laboratory of Intensive Care MedicineDepartment of Cellular and Molecular MedicineKU LeuvenLeuvenBelgium
| | - Bart Staels
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Philippe Lefebvre
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
| | - Jérôme Eeckhoute
- Inserm, CHU LilleInstitut Pasteur de LilleU1011‐EGIDUniversity of LilleLilleFrance
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Vankrunkelsven W, Dubois V, Derese I, Langouche L, Eeckhoute J, Van Den Berghe G, Vanhorebeek I. SAT-155 Temporal Activation of the Unfolded Protein Response and Concomitant Downregulation of Key Hepatic Transcription Factors in Critical Illness. J Endocr Soc 2019. [PMCID: PMC6552495 DOI: 10.1210/js.2019-sat-155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Background: Critically ill patients often develop multiple organ failure accompanied by profound metabolic and endocrine alterations. The pathogenesis is incompletely understood, but the development of cellular stress, including endoplasmic reticulum (ER) stress, might play a pivotal role (1). Indeed, markers of ER stress have been observed in critical illness, both in animal models and human patients, correlating with organ dysfunction (1). ER stress normally activates the unfolded protein response (UPR). The UPR follows a distinct temporal pattern, aimed at restoring ER homeostasis in the short term, but inducing apoptosis whenever ER stress becomes too severe or prolonged. During critical illness, the temporal activation pattern in liver has only been partially studied. In addition, the potential implications for liver function and metabolism are currently unknown. Methods: We quantified the hepatic expression of crucial markers of the 3 UPR branches and of key hepatic transcription factors in a clinically relevant fluid-resuscitated mouse model of sepsis. Mice were sacrificed at 10 hrs, 30 hrs or 3 days after cecal ligation and puncture in comparison with healthy pair-fed mice (n=15 per group per time point). We quantified the same markers in postmortem liver biopsies from patients admitted to the intensive care unit with sepsis (n=64), who died after a median ICU stay of 10 days (IQR 6-20 days), in comparison with matched patients undergoing elective restorative rectal surgery (n=18). Results: In septic mice, the UPR showed a distinct temporal pattern. In the acute phase (10-30 hrs), the PERK, IRE1α and ATF6 branches were all activated (p˂0.01). In the prolonged phase (3 days), the PERK and ATF6 branches were attenuated and only the IRE1α branch remained activated (p˂0.0001). The UPR activation in the acute phase coincided with a significant downregulation of key hepatic transcription factors important for normal liver function and metabolism, including Shp, FXR, Lrh1, PXR, Hnf6 and Foxa2 (p˂0.01). Several transcription factors remained significantly downregulated in the prolonged phase. ALT as liver damage marker correlated directly with several UPR markers and inversely with several transcription factors in the acute phase, but not in the prolonged phase. In postmortem liver biopsies of patients with sepsis, we only observed an upregulation of the IRE1α branch of the UPR, consistent with the pattern in prolonged critically ill mice. Also in patients, this coincided with a repression of several key hepatic transcription factors. Conclusion: The present findings suggest that patients admitted to the intensive care unit with sepsis develop a state of chronic ER stress in the liver, which might hamper normal hepatic function at least in part through the downregulation of key transcription factors. References: 1. Thiessen SE et al. BBA-Mol Basis Dis 2017, 1863, 2534-45
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