Labeling and isolating cell specific neuronal mitochondria and their functional analysis in mice post stroke.

Dendritic and axonal plasticity, which mediates neurobiological recovery after a stroke, critically depends on the mitochondrial function of neurons. To investigate, in vivo, neuronal mitochondrial function at the stroke recovery stage, we employed Mito-tag mice combined with cerebral cortical infection of AAV9 produced from plasmids carrying Cre-recombinase controlled by two neuronal promoters, synapsin-I (SYN1) and calmodulin-kinase IIa to induce expression of a hemagglutinin (HA)-tagged enhanced green fluorescence protein (EGFP) that localizes to mitochondrial outer membranes of SYN1 positive (SYN) and CaMKIIa positive (CaMKIIa) neurons. These mice were then subjected to permanent middle cerebral artery occlusion (MCAO) and sacrificed 14 days post stroke.

Mesenchymal-derived extracellular vesicles enhance microglia-mediated synapse remodeling after cortical injury in aging Rhesus monkeys.

Understanding the microglial neuro-immune interactions in the primate brain is vital to developing therapeutics for cortical injury, such as stroke or traumatic brain injury. Our previous work showed that mesenchymal-derived extracellular vesicles (MSC-EVs) enhanced motor recovery in aged rhesus monkeys following injury of primary motor cortex (M1), by promoting homeostatic ramified microglia, reducing injury-related neuronal hyperexcitability, and enhancing synaptic plasticity in perilesional cortices. A focal lesion was induced via surgical ablation of pial blood vessels over lying the cortical hand representation of M1 of aged female rhesus monkeys, that received intravenous infusions of either vehicle (veh) or EVs 24 h and again 14 days post-injury.

Plasminogen deficiency causes reduced angiogenesis and behavioral recovery after stroke in mice.

Plasminogen is involved in the process of angiogenesis; however, the underlying mechanism is unclear. Here, we investigated the potential contribution of plasmin/plasminogen in mediating angiogenesis and thereby contributing to functional recovery post-stroke. Wild-type plasminogen naive (Plg) mice and plasminogen knockout (Plg) mice were subjected to unilateral permanent middle cerebral artery occlusion (MCAo).

Axonal remodeling of the corticospinal tract during neurological recovery after stroke.

Stroke remains the leading cause of long-term disability. Hemiparesis is one of the most common post-stroke motor deficits and is largely attributed to loss or disruption of the motor signals from the affected motor cortex. As the only direct descending motor pathway, the corticospinal tract (CST) is the primary pathway to innervate spinal motor neurons, and thus, forms the neuroanatomical basis to control the peripheral muscles for voluntary movements.

MiR-17-92 enriched exosomes derived from multipotent mesenchymal stromal cells enhance axon-myelin remodeling and motor electrophysiological recovery after stroke.

MiR-17-92 cluster enriched exosomes derived from multipotent mesenchymal stromal cells (MSCs) increase functional recovery after stroke. Here, we investigate the mechanisms underlying this recovery. At 24 h (h) post transient middle cerebral artery occlusion, rats received control liposomes or exosomes derived from MSCs infected with pre-miR-17-92 expression lentivirus (Exo-miR-17-92) or control lentivirus (Exo-Con) intravenously.

Targeted tPA overexpression in denervated spinal motor neurons promotes stroke recovery in mice.

Our previous studies demonstrated that axonal remodeling of the corticospinal tract (CST) contributes to neurological recovery after stroke in rodents. The present study employed a novel non-invasive peripheral approach, to over-express tPA in denervated spinal motor neurons via recombinant adeno-associated virus (AAV) intramuscular injection in transgenic mice subjected to permanent middle cerebral artery occlusion (MCAo), in which the CST axons are specifically and completely labeled with yellow fluorescent protein (YFP). One day after surgery, mice were randomly selected to receive saline, AAV5-RFP, or tPA (1 × 10 viral particles) injected into the stroke-impaired forelimb muscles ( = 10/group).

MicroRNA cluster miR-17-92 Cluster in Exosomes Enhance Neuroplasticity and Functional Recovery After Stroke in Rats.

Background And Purpose: Multipotent mesenchymal stromal cell (MSC) harvested exosomes are hypothesized as the major paracrine effectors of MSCs. In vitro, the miR-17-92 cluster promotes oligodendrogenesis, neurogenesis, and axonal outgrowth. We, therefore, investigated whether the miR-17-92 cluster-enriched exosomes harvested from MSCs transfected with an miR-17-92 cluster plasmid enhance neurological recovery compared with control MSC-derived exosomes.

Secondary Release of Exosomes From Astrocytes Contributes to the Increase in Neural Plasticity and Improvement of Functional Recovery After Stroke in Rats Treated With Exosomes Harvested From MicroRNA 133b-Overexpressing Multipotent Mesenchymal Stromal Cells.

We previously demonstrated that multipotent mesenchymal stromal cells (MSCs) that overexpress microRNA 133b (miR-133b) significantly improve functional recovery in rats subjected to middle cerebral artery occlusion (MCAO) compared with naive MSCs and that exosomes generated from naive MSCs mediate the therapeutic benefits of MSC therapy for stroke. Here we investigated whether exosomes isolated from miR-133b-overexpressing MSCs (Ex-miR-133b+) exert amplified therapeutic effects. Rats subjected to 2 h of MCAO were intra-arterially injected with Ex-miR-133b+, exosomes from MSCs infected by blank vector (Ex-Con), or phosphate-buffered saline (PBS) and were sacrificed 28 days after MCAO.

Systemic administration of cell-free exosomes generated by human bone marrow derived mesenchymal stem cells cultured under 2D and 3D conditions improves functional recovery in rats after traumatic brain injury.

Multipotent human bone marrow derived mesenchymal stem cells (hMSCs) improve functional outcome after experimental traumatic brain injury (TBI). The present study was designed to investigate whether systemic administration of cell-free exosomes generated from hMSCs cultured in 2-dimensional (2D) conventional conditions or in 3-dimensional (3D) collagen scaffolds promote functional recovery and neurovascular remodeling in rats after TBI. Wistar rats were subjected to TBI induced by controlled cortical impact; 24 h later tail vein injection of exosomes derived from hMSCs cultured under 2D or 3D conditions or an equal number of liposomes as a treatment control were performed.

Effect of exosomes derived from multipluripotent mesenchymal stromal cells on functional recovery and neurovascular plasticity in rats after traumatic brain injury.

Object: Transplanted multipotent mesenchymal stromal cells (MSCs) improve functional recovery in rats after traumatic brain injury (TBI). In this study the authors tested a novel hypothesis that systemic administration of cell-free exosomes generated from MSCs promotes functional recovery and neurovascular remodeling in rats after TBI.

Methods: Two groups of 8 Wistar rats were subjected to TBI, followed 24 hours later by tail vein injection of 100 μg protein of exosomes derived from MSCs or an equal volume of vehicle (phosphate-buffered saline).

Exosomes/miRNAs as mediating cell-based therapy of stroke.

Cell-based therapy, e.g., multipotent mesenchymal stromal cell (MSC) treatment, shows promise for the treatment of various diseases.

The role of astrocytes in mediating exogenous cell-based restorative therapy for stroke.

Astrocytes have not been a major therapeutic target for the treatment of stroke, with most research emphasis on the neuron. Given the essential role that astrocytes play in maintaining physiological function of the central nervous system and the very rapid and sensitive reaction astrocytes have in response to cerebral injury or ischemic insult, we propose to replace the neurocentric view for treatment with a more nuanced astrocytic centered approach. In addition, after decades of effort in attempting to develop neuroprotective therapies, which target reduction of the ischemic lesion, there are no effective clinical treatments for stroke, aside from thrombolysis with tissue plasminogen activator, which is used in a small minority of patients.

Skimmin, a Coumarin from Hydrangea paniculata, Slows down the Progression of Membranous Glomerulonephritis by Anti-Inflammatory Effects and Inhibiting Immune Complex Deposition.

Skimmin is one of the major pharmacologically active molecules present in Hydrangea paniculata, a medical herb used in the traditional Chinese medicine as an anti-inflammatory agent. In the current study, we attempted to investigate its renoprotective activity and underlying mechanisms in a rat model of membranous glomerulonephritis induced by cationic bovine serum albumin (c-BSA). Sprague-Dawley (SD) rats were divided into five groups, including normal control, model control, Mycophenolate Mofetil-treated group, and two skimming-treated groups (15 mg/kg and 30 mg/kg).

Systemic administration of exosomes released from mesenchymal stromal cells promote functional recovery and neurovascular plasticity after stroke in rats.

Here, for the first time, we test a novel hypothesis that systemic treatment of stroke with exosomes derived from multipotent mesenchymal stromal cells (MSCs) promote neurovascular remodeling and functional recovery after stroke in rats. Adult male Wistar rats were subjected to 2 hours of middle cerebral artery occlusion (MCAo) followed by tail vein injection of 100 μg protein from MSC exosome precipitates or an equal volume of vehicle phosphate-buffered saline (PBS) (n=6/group) 24 hours later. Animals were killed at 28 days after stroke and histopathology and immunohistochemistry were employed to identify neurite remodeling, neurogenesis, and angiogenesis.

MiR-133b promotes neural plasticity and functional recovery after treatment of stroke with multipotent mesenchymal stromal cells in rats via transfer of exosome-enriched extracellular particles.

To test, in vivo, the hypothesis that exosomes from multipotent mesenchymal stromal cells (MSCs) mediate microRNA 133b (miR-133b) transfer which promotes neurological recovery from stroke, we used knockin and knockdown technologies to upregulate or downregulate the miR-133b level in MSCs (miR-133b(+) MSCs or miR-133b(-) MSCs) and their corresponding exosomes, respectively. Rats were subjected to middle cerebral artery occlusion (MCAo) and were treated with naïve MSCs, miR-133b(+) MSCs, or miR-133b(-) MSC at 1 day after MCAo. Compared with controls, rats receiving naïve MSC treatment significantly improved functional recovery and exhibited increased axonal plasticity and neurite remodeling in the ischemic boundary zone (IBZ) at day 14 after MCAo.

Multipotent mesenchymal stromal cells decrease transforming growth factor β1 expression in microglia/macrophages and down-regulate plasminogen activator inhibitor 1 expression in astrocytes after stroke.

Multipotent mesenchymal stromal cells (MSCs) decrease the expression of transforming growth factor β1 (TGFβ1) in astrocytes and subsequently decrease astrocytic plasminogen activator inhibitor 1 (PAI-1) level in an autocrine manner. Since activated microglia/macrophages are also a source of TGFβ1 after stroke, we therefore tested whether MSCs regulate TGFβ1 expression in microglia/macrophages and subsequently alters PAI-1 expression after ischemia. TGFβ1 and its downstream effector phosphorylated SMAD 2/3 (p-SMAD 2/3) were measured in mice subjected to middle cerebral artery occlusion (MCAo).

Exosome-mediated transfer of miR-133b from multipotent mesenchymal stromal cells to neural cells contributes to neurite outgrowth.

Multipotent mesenchymal stromal cells (MSCs) have potential therapeutic benefit for the treatment of neurological diseases and injury. MSCs interact with and alter brain parenchymal cells by direct cell-cell communication and/or by indirect secretion of factors and thereby promote functional recovery. In this study, we found that MSC treatment of rats subjected to middle cerebral artery occlusion (MCAo) significantly increased microRNA 133b (miR-133b) level in the ipsilateral hemisphere.

Subacute intranasal administration of tissue plasminogen activator increases functional recovery and axonal remodeling after stroke in rats.

As a thrombolytic agent, application of recombinant tissue plasminogen activator (tPA) to ischemic stroke is limited by the narrow time window and side effects on brain edema and hemorrhage. This study examined whether tPA, administered by intranasal delivery directly targeting the brain and spinal cord, provides therapeutic benefit during the subacute phase after stroke. Adult male Wistar rats were subjected to permanent right middle cerebral artery occlusion (MCAo).

Multipotent mesenchymal stromal cells increase tPA expression and concomitantly decrease PAI-1 expression in astrocytes through the sonic hedgehog signaling pathway after stroke (in vitro study).

Multipotent mesenchymal stromal cells (MSCs) increase tissue plasminogen activator (tPA) activity in astrocytes of the ischemic boundary zone, leading to increased neurite outgrowth in the brain. To probe the mechanisms that underlie MSC-mediated activation of tPA, we investigated the morphogenetic gene, sonic hedgehog (Shh) pathway. In vitro oxygen and glucose deprivation and coculture of astrocytes and MSCs were used to mimic an in vivo ischemic condition.

Endogenous tissue plasminogen activator mediates bone marrow stromal cell-induced neurite remodeling after stroke in mice.

Background And Purpose: Bone marrow stromal cells (BMSC) decrease neurological deficits in rodents after stroke and concomitantly induce extensive neurite remodeling in the brain, which highly correlates with the improvement of neurological function. We investigated the effects of endogenous tissue plasminogen activator (tPA) on neurite remodeling after BMSC treatment.

Methods: Adult C57BL/6 wild-type (WT) mice and tPA knockout (tPA(-/-)) mice were subjected to middle cerebral artery occlusion, followed by an injection of 1×10(6) BMSC (n=18) or phosphate-buffered saline (n=18) into the tail vein 24 hours later.

Increasing tPA activity in astrocytes induced by multipotent mesenchymal stromal cells facilitate neurite outgrowth after stroke in the mouse.

We demonstrate that tissue plasminogen activator (tPA) and its inhibitors contribute to neurite outgrowth in the central nervous system (CNS) after treatment of stroke with multipotent mesenchymal stromal cells (MSCs). In vivo, administration of MSCs to mice subjected to middle cerebral artery occlusion (MCAo) significantly increased activation of tPA and downregulated PAI-1 levels in the ischemic boundary zone (IBZ) compared with control PBS treated mice, concurrently with increases of myelinated axons and synaptophysin. In vitro, MSCs significantly increased tPA levels and concomitantly reduced plasminogen activator inhibitor 1 (PAI-1) expression in astrocytes under normal and oxygen and glucose deprivation (OGD) conditions.

XLF-III-43, a novel coumarin-aspirin compound, prevents diabetic nephropathy in rats via inhibiting advanced glycation end products.

Advanced glycation end products (AGE) have been implicated in the pathogenesis of diabetic complications. The purpose of this study was to examine the novel coumarin-aspirin compound XLF-III-43 in the inhibition of AGE formation in diabetic nephropathy. In vitro analysis showed XLF-III-43 in a dose-dependent manner decreased glucose induced formation of glycation adducts on albumin and inhibited AGE-lysozyme crosslinking.

Activity of FB2, a novel dual Abl/Src tyrosine kinase inhibitor, against imatinib-resistant chronic myeloid leukemia in vivo and in vitro.

FB2 is a novel Abl/Src dual tyrosine kinase inhibitor which is designed to overcome imatinib resistance. Besides imatinib-sensitive cell lines (K562), FB2 significantly inhibited the growth of imatinib-resistant cell lines of different resistance mechanisms (K562/G5.0 and K562/G01), and decreased the expression of autophosphorylation of Bcr/Abl, c-Src and Lyn kinases on them.