Intravenous transplants of human adipose-derived stem cell protect the brain from traumatic brain injury-induced neurodegeneration and motor and cognitive impairments: cell graft biodistribution and soluble factors in young and aged rats.

Traumatic brain injury (TBI) survivors exhibit motor and cognitive symptoms from the primary injury that can become aggravated over time because of secondary cell death. In the present in vivo study, we examined the beneficial effects of human adipose-derived stem cells (hADSCs) in a controlled cortical impact model of mild TBI using young (6 months) and aged (20 months) F344 rats. Animals were transplanted intravenously with 4 × 10(6) hADSCs (Tx), conditioned media (CM), or vehicle (unconditioned media) at 3 h after TBI. Significant amelioration of motor and cognitive functions was revealed in young, but not aged, Tx and CM groups. Fluorescent imaging in vivo and ex vivo revealed 1,1' dioactadecyl-3-3-3',3'-tetramethylindotricarbocyanine iodide-labeled hADSCs in peripheral organs and brain after TBI. Spatiotemporal deposition of hADSCs differed between young and aged rats, most notably reduced migration to the aged spleen. Significant reduction in cortical damage and hippocampal cell loss was observed in both Tx and CM groups in young rats, whereas less neuroprotection was detected in the aged rats and mainly in the Tx group but not the CM group. CM harvested from hADSCs with silencing of either NEAT1 (nuclear enriched abundant transcript 1) or MALAT1 (metastasis associated lung adenocarcinoma transcript 1), long noncoding RNAs (lncRNAs) known to play a role in gene expression, lost the efficacy in our model. Altogether, hADSCs are promising therapeutic cells for TBI, and lncRNAs in the secretome is an important mechanism of cell therapy. Furthermore, hADSCs showed reduced efficacy in aged rats, which may in part result from decreased homing of the cells to the spleen.

Ischemic stroke brain sends indirect cell death signals to the heart.

BACKGROUND AND PURPOSE: Ischemic stroke is a leading cause of mortality and morbidity in the world and may be associated with cardiac myocyte vulnerability. However, it remains uncertain how an ischemic brain contributes to cardiac alternations. Here, we used experimental stroke models to reveal the pathological effects of the ischemic brain on the heart. METHODS: For the in vitro study, primary rat neuronal cells were subjected to 90-minute oxygen-glucose deprivation (OGD). Two hours after OGD, the supernatant was collected and cryopreserved until further biological assays. Primary rat cardiac myocytes were exposed to ischemic-reperfusion injury and subsequently to the supernatant derived from either the OGD or non-OGD-exposed primary rat neuronal cells for 2, 6, 24, or 48 hours. Thereafter, we measured cell viability and mitochondrial activity in rat cardiac myocytes. For the in vivo study, we subjected adult rats to transient middle cerebral artery occlusion, and their brains and hearts were harvested for immunohistochemical analyses at 3 months later. RESULTS: The supernatant from the OGD, but not the non-OGD-exposed primary rat neuronal cells, caused significant reduction in cell viability and mitochondrial activity in rat cardiac myocytes. Ischemic stroke animals displayed phenotypic expression of necrosis, apoptosis, and autophagy in their hearts, which paralleled the detection of these same cell death markers in their brains. CONCLUSIONS: Ischemic stroke was accompanied by cardiac myocyte death, indicating a close pathological link between brain and heart. These results suggest a vigilant assessment of the heart condition in stroke patients, likely requiring the need to treat systemic cardiac symptoms after an ischemic brain episode.

Vasculogenesis in experimental stroke after human cerebral endothelial cell transplantation.

BACKGROUND AND PURPOSE: Despite the reported functional recovery in transplanted stroke models and patients, the mechanism of action underlying stem cell therapy remains not well understood. Here, we examined the role of stem cell-mediated vascular repair in stroke. METHODS: Adult rats were exposed to transient occlusion of the middle cerebral artery and 3 hours later randomly stereotaxically transplantated with 100K, 200K, or 400K human cerebral endothelial cell 6 viable cells or vehicle. Animals underwent neurological examination and motor test up to day 7 after transplantation then euthanized for immunostaining against neuronal, vascular, and specific human antigens. A parallel in vitro study cocultured rat primary neuronal cells with human cerebral endothelial cell 6 under oxygen-glucose deprivation and treated with vascular endothelial growth factor (VEGF) and anti-VEGF. RESULTS: Stroke animals that received vehicle infusion displayed typical occlusion of the middle cerebral artery-induced behavioral impairments that were dose-dependently reduced in transplanted stroke animals at days 3 and 7 after transplantation and accompanied by increased expression of host neuronal and vascular markers adjacent to the transplanted cells. Some transplanted cells showed a microvascular phenotype and juxtaposed to the host vasculature. Infarct volume in transplanted stroke animals was significantly smaller than vehicle-infused stroke animals. Moreover, rat neurons cocultured with human cerebral endothelial cell 6 or treated with VEGF exhibited significantly less oxygen-glucose deprivation-induced cell death that was blocked by anti-VEGF treatment. CONCLUSIONS: We found attenuation of behavioral and histological deficits coupled with robust vasculogenesis and neurogenesis in endothelial cell-transplanted stroke animals, suggesting that targeting vascular repair sets in motion a regenerative process in experimental stroke possibly via the VEGF pathway.