Intramyocardial Injection of Human Adipose-Derived Stem Cells Ameliorates Cognitive Deficit By Regulating Oxidative Stress-Mediated Hippocampal Damage After Myocardial Infarction

Abstract

Cognitive impairment is a serious side effect of post-myocardial infarction (MI) course. We have recently demonstrated that human adipose-derived stem cells (hADSCs) ameliorated myocardial injury after MI by attenuating reactive oxygen species (ROS) levels. Here, we studied whether the beneficial effects of intramyocardial hADSC transplantation can extend to the brain and how they may attenuate cognitive dysfunction via modulating ROS after MI. After coronary ligation, male Wistar rats were randomized via an intramyocardial route to receive either vehicle, hADSC transplantation (1x106 cells), or the combination of hADSCs and 3-Morpholinosydnonimine (SIN-1, a peroxynitrite donor). Whether hADSCs migrated into the hippocampus was assessed by using human-specific primers in qPCR reactions. Passive avoidance test was used to assess cognitive performance. Postinfarction was associated with increased oxidative stress in myocardium, circulation and hippocampus. This was coupled with decreased numbers of dendritic spines as well as a significant downregulation of synaptic plasticity consisting of synaptophysin and PSD95. Step through latency during passive avoidance test was impaired in vehicle-treated rats after MI. Intramyocardial hADSC injection exerted therapeutic benefits in improving cardiac function and cognitive impairment. None of hADSCs were detected in rat’s hippocampus at the 3th day after intramyocardial injection. The beneficial effects of hADSCs on MI-induced histological and cognitive changes were abolished after adding SIN-1. MI-induced ROS attacked the hippocampus to induce neurodegeneration, resulting in cognitive deficit. The remotely intramyocardial administration of hADSCs, has the capacity of improved synaptic neuroplasticity in hippocampus mediated by ROS, not the cell engraftment, after MI.

Advances in the role of STAT3 in macrophage polarization

“…Previous research suggests that IL-10 may play a preventive function in the prevention of chronic fibroproliferative disorders (96). Adiposederived stem cells stimulate macrophage M2 polarization via PI3K/ AKT/STAT3-dependent pathway, which suppresses fibroblast development into myofibroblasts via local IL-10 production, lowering extracellular matrix synthesis and, ultimately, cardiac fibrosis (97,98). Type Ig phosphatidylinositol phosphate kinase is a phosphatidylinositol kinase that produces phosphatidylinositol bisphosphate in cells and increases STAT3 phosphorylation by stimulating activation of the PI3K/AKT signaling pathway, which in turn promotes the C-C motif chemokine ligand 2 transcription to improve tumor-associated macrophage recruitment (99).…”