Inhibition of SREBP Improves Cardiac Lipidopathy, Improves Endoplasmic Reticulum Stress, and Modulates Chronic Chagas Cardiomyopathy

Janeesh Plakkal Ayyappan, Kezia Lizardo, Sean Wang, Edward Yurkow, Jyothi F. Nagajyothi

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

Background: Trypanosoma cruzi is an intracellular parasite that causes debilitating chronic Chagas cardiomyopathy (CCM), for which there is no effective drug or vaccine. Previously, we demonstrated increased cardiac lipid accumulation and endoplasmic reticulum stress in mice with CCM. Increased endoplasmic reticulum stress may lead to uncontrolled SREBP (sterol regulatory element-binding protein) activation and lipotoxicity in the myocardium during the intermediate stage of infection and result in progression to chronic CCM. Therefore, we investigated whether inhibiting SREBP activation modulates CCM progression in T cruzi–infected mice. Methods and Results: T cruzi–infected cultured cardiomyocytes (3:1 multiplicity of infection; 24 hours postinfection) were incubated with betulin (3 μmol/L per mL), an SREBP inhibitor, for 24 hours. Quantitative polymerase chain reaction and Western blotting analyses demonstrated a significant reduction in SREBP activation, lipid biosynthesis, and endoplasmic reticulum stress in betulin-treated infected cells compared with untreated cells. T cruzi infected (103 trypomastigotes of the Brazil strain) Swiss mice were fed a customized diet containing betulin during the intermediate stage (40 days postinfection) until the chronic stage (120 DPI). Cardiac ultrasound imaging and histological and biochemical analyses demonstrated anatomical and functional improvements in betulin-treated, infected mice compared with untreated controls: we observed a significant reduction in cholesterol/fatty acid synthesis that may result in the observed cardiac reduction in cardiac lipid accumulation, mitochondrial and endoplasmic reticulum stress, and ventricular enlargement. Conclusions: Our study (in vitro and vivo) demonstrates that inhibition of cardiac SREBP activation reduces cardiac damage during T cruzi infection and modulates CCM in a murine Chagas model.

Original languageEnglish (US)
Article numbere014255
JournalJournal of the American Heart Association
Volume9
Issue number3
DOIs
StatePublished - Feb 4 2020

All Science Journal Classification (ASJC) codes

  • Cardiology and Cardiovascular Medicine

Keywords

  • Chagas disease
  • SREBP activation
  • betulin
  • cardiomyopathy
  • endoplasmic reticulum stress
  • mitochondrial stress

Fingerprint

Dive into the research topics of 'Inhibition of SREBP Improves Cardiac Lipidopathy, Improves Endoplasmic Reticulum Stress, and Modulates Chronic Chagas Cardiomyopathy'. Together they form a unique fingerprint.

Cite this