Identification of a leucine-mediated threshold effect governing macrophage mTOR signalling and cardiovascular risk.


Journal

Nature metabolism
ISSN: 2522-5812
Titre abrégé: Nat Metab
Pays: Germany
ID NLM: 101736592

Informations de publication

Date de publication:
Feb 2024
Historique:
received: 23 02 2022
accepted: 09 01 2024
medline: 27 2 2024
pubmed: 27 2 2024
entrez: 26 2 2024
Statut: ppublish

Résumé

High protein intake is common in western societies and is often promoted as part of a healthy lifestyle; however, amino-acid-mediated mammalian target of rapamycin (mTOR) signalling in macrophages has been implicated in the pathogenesis of ischaemic cardiovascular disease. In a series of clinical studies on male and female participants ( NCT03946774 and NCT03994367 ) that involved graded amounts of protein ingestion together with detailed plasma amino acid analysis and human monocyte/macrophage experiments, we identify leucine as the key activator of mTOR signalling in macrophages. We describe a threshold effect of high protein intake and circulating leucine on monocytes/macrophages wherein only protein in excess of ∼25 g per meal induces mTOR activation and functional effects. By designing specific diets modified in protein and leucine content representative of the intake in the general population, we confirm this threshold effect in mouse models and find ingestion of protein in excess of ∼22% of dietary energy requirements drives atherosclerosis in male mice. These data demonstrate a mechanistic basis for the adverse impact of excessive dietary protein on cardiovascular risk.

Identifiants

pubmed: 38409323
doi: 10.1038/s42255-024-00984-2
pii: 10.1038/s42255-024-00984-2
doi:

Types de publication

Journal Article

Langues

eng

Sous-ensembles de citation

IM

Pagination

359-377

Subventions

Organisme : NHLBI NIH HHS
ID : R01 HL125838
Pays : United States
Organisme : NHLBI NIH HHS
ID : R01 HL159461
Pays : United States
Organisme : NIDDK NIH HHS
ID : R01 DK121560
Pays : United States
Organisme : NIDDK NIH HHS
ID : P30 DK056341
Pays : United States
Organisme : NIDDK NIH HHS
ID : P30 DK020579
Pays : United States
Organisme : BLRD VA
ID : I01 BX003415
Pays : United States
Organisme : NCATS NIH HHS
ID : UL1 TR000448
Pays : United States
Organisme : NCATS NIH HHS
ID : UL1 TR000448
Pays : United States
Organisme : NHLBI NIH HHS
ID : T32 HL134635
Pays : United States
Organisme : NHLBI NIH HHS
ID : T32 HL134635
Pays : United States

Informations de copyright

© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.

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Auteurs

Xiangyu Zhang (X)

Department of Medicine and Vascular Medicine Institute, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA, USA.
Pittsburgh VA Medical Center, Pittsburgh, PA, USA.

Divya Kapoor (D)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.
John Cochran VA Medical Center, St Louis, MO, USA.

Se-Jin Jeong (SJ)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Alan Fappi (A)

Division of Nutritional Science and Obesity Medicine, Washington University School of Medicine, St. Louis, MO, USA.
Departments of Medicine and Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA.

Jeremiah Stitham (J)

Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St Louis, MO, USA.

Vasavi Shabrish (V)

Division of Nutritional Science and Obesity Medicine, Washington University School of Medicine, St. Louis, MO, USA.
Departments of Medicine and Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA.

Ismail Sergin (I)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Eman Yousif (E)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Astrid Rodriguez-Velez (A)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Yu-Sheng Yeh (YS)

Department of Medicine and Vascular Medicine Institute, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA, USA.
Pittsburgh VA Medical Center, Pittsburgh, PA, USA.

Arick Park (A)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Arif Yurdagul (A)

Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, LA, USA.

Oren Rom (O)

Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, LA, USA.

Slava Epelman (S)

Peter Munk Cardiac Center and University Health Network, University of Toronto, Toronto, Canada.

Joel D Schilling (JD)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Marco Sardiello (M)

Department of Pediatrics, Washington University School of Medicine, St Louis, MO, USA.

Abhinav Diwan (A)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.
John Cochran VA Medical Center, St Louis, MO, USA.

Jaehyung Cho (J)

Division of Hematology, Department of Medicine, Washington University School of Medicine, St Louis, MO, USA.
Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, USA.

Nathan O Stitziel (NO)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.

Ali Javaheri (A)

Cardiovascular Division, Washington University School of Medicine, St Louis, MO, USA.
John Cochran VA Medical Center, St Louis, MO, USA.

Irfan J Lodhi (IJ)

Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St Louis, MO, USA.

Bettina Mittendorfer (B)

Division of Nutritional Science and Obesity Medicine, Washington University School of Medicine, St. Louis, MO, USA. b.mittendorfer@missouri.edu.
Departments of Medicine and Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, USA. b.mittendorfer@missouri.edu.

Babak Razani (B)

Department of Medicine and Vascular Medicine Institute, University of Pittsburgh School of Medicine and UPMC, Pittsburgh, PA, USA. brazani@pitt.edu.
Pittsburgh VA Medical Center, Pittsburgh, PA, USA. brazani@pitt.edu.

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