Role of the mTOR Signalling Pathway in Human Sepsis-Induced Myocardial Dysfunction

Can J Cardiol. 2019 Jul;35(7):875-883. doi: 10.1016/j.cjca.2019.03.022. Epub 2019 Apr 4.

Abstract

Background: Sepsis-induced myocardial dysfunction (SIMD) is a life-threatening complication of sepsis. Mammalian target of rapamycin (mTOR) signalling pathway is significantly associated with SIMD in an animal model; however, there have been no clinical studies of the association in humans.

Methods: We enrolled 88 patients with sepsis who were admitted to the intensive care unit (ICU) between April 2017, and April 2018. Biochemical indexes, hemodynamic parameters, and bedside echocardiographic parameters were recorded. Serum levels of mTOR, phosphorylated ribosome S6 protein kinase (PS6K), microtubule-associated protein light chain 3 type II (LC3B), Bcl-2-interacting mediator of cell death (BIM), interleukin 6, interleukin 10, and interferon-γ were examined.

Results: Compared with non-SIMD patients, patients with SIMD had higher ICU and 28-day mortality, PS6K and BIM levels, but lower LC3B levels. Serum PS6K levels in patients with SIMD were significantly negatively and positively correlated with LC3B and BIM, respectively. Multivariate regression analysis revealed that PS6K concentration at admission was an independent predictor of 28-day mortality. Receiver operating characteristic curve analysis indicated that a PS6K concentration cutoff of 42.43 pg/mL at ICU admission could predict the incidence of SIMD with a sensitivity and specificity of 91.7% and 96.2%, whereas a cutoff concentration of 41.17 pg/mL PS6K could predict 28-day mortality with a sensitivity and specificity of 83.3% and 54.3%, respectively.

Conclusions: Patients with sepsis and SIMD had higher ICU and 28-day mortality. Higher serum PS6K concentrations were significantly associated with SIMD incidence and 28-day mortality, suggesting that activation of the mTOR pathway may play a major role in SIMD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bcl-2-Like Protein 11 / blood
  • Biomarkers / blood
  • Cardiac Output, Low / epidemiology
  • China / epidemiology
  • Female
  • Hospital Mortality*
  • Humans
  • Intensive Care Units*
  • Length of Stay / statistics & numerical data
  • Male
  • Microtubule-Associated Proteins / blood
  • Middle Aged
  • Patient Admission / statistics & numerical data
  • Prospective Studies
  • Ribosomal Protein S6 Kinases / blood
  • Sensitivity and Specificity
  • Sepsis / blood*
  • Sepsis / epidemiology
  • Stroke Volume
  • TOR Serine-Threonine Kinases / blood*
  • Ventricular Dysfunction, Left / blood*
  • Ventricular Dysfunction, Left / epidemiology

Substances

  • Bcl-2-Like Protein 11
  • Biomarkers
  • MAP1LC3B protein, human
  • Microtubule-Associated Proteins
  • MTOR protein, human
  • Ribosomal Protein S6 Kinases
  • TOR Serine-Threonine Kinases