1. Pericytes protect rats and mice from sepsis-induced injuries by maintaining vascular reactivity and barrier function: implication of miRNAs and microvesicles.
- Author
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Zhang ZS, Liu YY, He SS, Bao DQ, Wang HC, Zhang J, Peng XY, Zang JT, Zhu Y, Wu Y, Li QH, Li T, and Liu LM
- Subjects
- Animals, Mice, Rats, Capillary Permeability physiology, Connexin 43 metabolism, Endothelial Cells metabolism, Lipopolysaccharides pharmacology, Pericytes metabolism, Rats, Sprague-Dawley, MicroRNAs pharmacology, Sepsis
- Abstract
Background: Vascular hyporeactivity and leakage are key pathophysiologic features that produce multi-organ damage upon sepsis. We hypothesized that pericytes, a group of pluripotent cells that maintain vascular integrity and tension, are protective against sepsis via regulating vascular reactivity and permeability., Methods: We conducted a series of in vivo experiments using wild-type (WT), platelet-derived growth factor receptor beta (PDGFR-β)-Cre + mT/mG transgenic mice and Tie2-Cre + Cx43
flox/flox mice to examine the relative contribution of pericytes in sepsis, either induced by cecal ligation and puncture (CLP) or lipopolysaccharide (LPS) challenge. In a separate set of experiments with Sprague-Dawley (SD) rats, pericytes were depleted using CP-673451, a selective PDGFR-β inhibitor, at a dosage of 40 mg/(kg·d) for 7 consecutive days. Cultured pericytes, vascular endothelial cells (VECs) and vascular smooth muscle cells (VSMCs) were used for mechanistic investigations. The effects of pericytes and pericyte-derived microvesicles (PCMVs) and candidate miRNAs on vascular reactivity and barrier function were also examined., Results: CLP and LPS induced severe injury/loss of pericytes, vascular hyporeactivity and leakage (P < 0.05). Transplantation with exogenous pericytes protected vascular reactivity and barrier function via microvessel colonization (P < 0.05). Cx43 knockout in either pericytes or VECs reduced pericyte colonization in microvessels (P < 0.05). Additionally, PCMVs transferred miR-145 and miR-132 to VSMCs and VECs, respectively, exerting a protective effect on vascular reactivity and barrier function after sepsis (P < 0.05). miR-145 primarily improved the contractile response of VSMCs by activating the sphingosine kinase 2 (Sphk2)/sphingosine-1-phosphate receptor (S1PR)1/phosphorylation of myosin light chain 20 pathway, whereas miR-132 effectively improved the barrier function of VECs by activating the Sphk2/S1PR2/zonula occludens-1 and vascular endothelial-cadherin pathways., Conclusions: Pericytes are protective against sepsis through regulating vascular reactivity and barrier function. Possible mechanisms include both direct colonization of microvasculature and secretion of PCMVs., (© 2023. The Author(s).)- Published
- 2023
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