The Small GTPases Rab27b Regulates Mitochondrial Fatty Acid Oxidative Metabolism of Cardiac Mesenchymal Stem Cells

Yue Jin, Yan Shen, Xuan Su, Jingwen Cai, Yutao Liu, Neal L. Weintraub, Yaoliang Tang

Research output: Contribution to journalArticle


Cardiac mesenchymal stem cells (C-MSCs) are endogenous cardiac stromal cells that play a crucial role in maintaining normal cardiac function. Rab27b is a member of the small GTPase Rab family that controls membrane trafficking and the secretion of exosomes. However, its role in regulating energy metabolism in C-MSC is unclear. In this study, we analyzed mitochondrial oxidative phosphorylation by quantifying cellular oxygen consumption rate (OCR) and quantified the extracellular acidification rate (ECAR) in C-MSC with/without Rab27b knockdown. Knockdown of Rab27b increased glycolysis, but significantly reduced mitochondrial oxidative phosphorylation (OXPHOS) with loss of mitochondrial membrane potential in C-MSC. Furthermore, knockdown of Rab27b reduced H3k4me3 expression in C-MSC and selectively decreased the expression of the essential genes involved in β-oxidation, tricarboxylic acid cycle (TCA), and electron transport chain (ETC). Taken together, our findings highlight a novel role for Rab27b in maintaining fatty acid oxidation in C-MSCs.

Original languageEnglish (US)
Article number209
JournalFrontiers in Cell and Developmental Biology
StatePublished - Apr 15 2020



  • cardiac mesenchymal stem cells
  • exosome
  • fatty acid oxidation
  • mitochondrial oxidative metabolism
  • Rab27b

ASJC Scopus subject areas

  • Developmental Biology
  • Cell Biology

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