Human umbilical cord derived mesenchymal stem cells overexpressing HO‐1 attenuate neural injury and enhance functional recovery by inhibiting inflammation in stroke mice

Abstract

AimsThe current evidence demonstrates that mesenchymal stem cells (MSCs) hold therapeutic potential for ischemic stroke. However, it remains unclear how changes in the secretion of MSC cytokines following the overexpression of heme oxygenase‐1 (HO‐1) impact excessive inflammatory activation in a mouse ischemic stroke model. This study investigated this aspect and provided further insights.MethodsThe middle cerebral artery occlusion (MCAO) mouse model was established, and subsequent injections of MSC, MSCHO‐1, or PBS solutions of equal volume were administered via the mice's tail vein. Histopathological analysis was conducted on Days 3 and 28 post‐MCAO to observe morphological changes in brain slices. mRNA expression levels of various factors, including IL‐1β, IL‐6, IL‐17, TNF‐α, IL‐1Ra, IL‐4, IL‐10, TGF‐β, were quantified. The effects of MSCHO‐1 treatment on neurons, microglia, and astrocytes were observed using immunofluorescence after transplantation. The polarization direction of macrophages/microglia was also detected using flow cytometry.ResultsThe results showed that the expression of anti‐inflammatory factors in the MSCHO‐1 group increased while that of pro‐inflammatory factors decreased. Small animal fluorescence studies and immunofluorescence assays showed that the homing function of MSCsHO‐1 was unaffected, leading to a substantial accumulation of MSCsHO‐1 in the cerebral ischemic region within 24 h. Neurons were less damaged, activation and proliferation of microglia were reduced, and polarization of microglia to the M2 type increased after MSCHO‐1 transplantation. Furthermore, after transplantation of MSCsHO‐1, the mortality of mice decreased, and motor function improved significantly.ConclusionThe findings indicate that MSCs overexpressing HO‐1 exhibited significant therapeutic effects against hyper‐inflammatory injury after stroke in mice, ultimately promoting recovery after ischemic stroke.

Neuroprotective effect of tanshinone IIA-modified mesenchymal stem cells in a lipopolysaccharide-induced neuroinflammation model

“…This modified approach to MSC provides valuable insights into the development of treatments for neuroinflammation-related diseases. At the same time, although many previous studies have confirmed that MSC injected through the tail vein can enter brain tissue via the blood-brain barrier [ 19 , 45 ], we can still continue relevant research work in future studies. In order to better understand the mechanism of action of MSC, we plan to use Dil labeling technology to label MSC in subsequent studies and then inject them into mice via the tail vein.…”