Dataset Information

Exosomes Secreted by the Cocultures of Normal and Oxygen-Glucose-Deprived Stem Cells Improve Post-stroke Outcome.

ABSTRACT: Emerging stroke literature suggests that treatment of experimentally induced stroke with stem cells offered post-stroke neuroprotection via exosomes produced by these cells. Treatment with exosomes has great potential to overcome the limitations associated with cell-based therapies. However, in our preliminary studies, we noticed that the exosomes released from human umbilical cord blood-derived mesenchymal stem cells (MSCs) under standard culture conditions did not improve the post-stroke neurological outcome. Because of this apparent discrepancy, we hypothesized that exosome characteristics vary with the conditions of their production. Specifically, we suggest that the exosomes produced from the cocultures of regular and oxygen-glucose-deprived (OGD) MSCs in vitro would represent the exosomes produced from MSCs that are exposed to ischemic brain cells in vivo, and offer similar therapeutic benefits that the cell treatment would provide. We tested the efficacy of therapy with exosomes secreted from human umbilical cord blood (HUCB)-derived MSCs under in vitro hypoxic conditions on post-stroke brain damage and neurological outcome in a rat model of transient focal cerebral ischemia. We performed the TTC staining procedure as well as the neurological tests including the modified neurological severity scores (mNSS), the modified adhesive removal (sticky-tape), and the beam walking tests before ischemia and at regular intervals until 7 days reperfusion. Treatment with exosomes obtained from the cocultures of normal and OGD-induced MSCs reduced the infarct size and ipsilateral hemisphere swelling, preserved the neurological function, and facilitated the recovery of stroke-induced rats. Based on the results, we conclude that the treatment with exosomes secreted from MSCs at appropriate experimental conditions attenuates the post-stroke brain damage and improves the neurological outcome.

SUBMITTER: Nalamolu KR

PROVIDER: S-EPMC7272187 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Exosomes Secreted by the Cocultures of Normal and Oxygen-Glucose-Deprived Stem Cells Improve Post-stroke Outcome.

Nalamolu Koteswara Rao KR Venkatesh Ishwarya I Mohandass Adithya A Klopfenstein Jeffrey D JD Pinson David M DM Wang David Z DZ Kunamneni Adinarayana A Veeravalli Krishna Kumar KK

Neuromolecular medicine 20190510 4

Emerging stroke literature suggests that treatment of experimentally induced stroke with stem cells offered post-stroke neuroprotection via exosomes produced by these cells. Treatment with exosomes has great potential to overcome the limitations associated with cell-based therapies. However, in our preliminary studies, we noticed that the exosomes released from human umbilical cord blood-derived mesenchymal stem cells (MSCs) under standard culture conditions did not improve the post-stroke neuro ...[more]

PMID: 31077035

Similar Datasets

Project description:Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxidative effects and has been used to treat cardiovascular and cerebrovascular diseases in China. However, the mechanisms by which scutellarin mediates neuroprotection in cerebral ischemia remain unclear. The interaction between scutellarin and nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2) was assessed by molecular docking study, which showed that scutellarin selectively binds to NOX2 with high affinity. Cultures of primary astrocytes isolated from the cerebral cortex of neonatal Sprague-Dawley rats were pretreated with 2, 10 or 50 ?M scutellarin for 30 minutes. The astrocytes were then subjected to oxygen/glucose deprivation by incubation for 2 hours in glucose-free Dulbecco's modified Eagle's medium in a 95% N2/5% CO2 incubator, followed by simulated reperfusion for 22 hours. Cell viability was assessed by cell counting kit-8 assay. Expression levels of NOX2, connexin 43 and caspase-3 were assessed by western blot assay. Reactive oxygen species were measured spectrophotometrically. Pretreatment with 10 or 50 ?M scutellarin substantially increased viability, reduced the expression of NOX2 and caspase-3, increased the expression of connexin 43, and diminished the levels of reactive oxygen species in astrocytes subjected to ischemia-reperfusion. We also assessed the effects of scutellarin in vivo in the rat transient middle cerebral artery occlusion model of cerebral ischemia-reperfusion injury. Rats were given intraperitoneal injection of 100 mg/kg scutellarin 2 hours before surgery. The Bederson scale was used to assess neurological deficit, and 2,3,5-triphenyltetrazolium chloride staining was used to measure infarct size. Western blot assay was used to assess expression of NOX2 and connexin 43 in brain tissue. Enzyme-linked immunosorbent assay was used to detect 8-hydroxydeoxyguanosine (8-OHdG), 4-hydroxy-2-nonenal (4-HNE) and 3-nitrotyrosin (3-NT) in brain tissue. Immunofluorescence double staining was used to determine the co-expression of caspase-3 and NeuN. Pretreatment with scutellarin improved the neurological function of rats with focal cerebral ischemia, reduced infarct size, diminished the expression of NOX2, reduced levels of 8-OHdG, 4-HNE and 3-NT, and reduced the number of cells co-expressing caspase-3 and NeuN in the injured brain tissue. Furthermore, we examined the effect of the NOX2 inhibitor apocynin. Apocynin substantially increased connexin 43 expression in vivo and in vitro. Collectively, our findings suggest that scutellarin protects against ischemic injury in vitro and in vivo by downregulating NOX2, upregulating connexin 43, decreasing oxidative damage, and reducing apoptotic cell death.

Project description:Background: Cerebral ischemia-reperfusion (I/R) injury can lead to severe dysfunction, and its treatment is difficult. It is reported that nucleotide-binding domain and leucine-rich repeat family protein 3 (NLRP3) inflammasome-mediated cell pyroptosis is an important part of cerebral I/R injury and the activation of autophagy can inhibit pyroptosis in some tissue injury. Our previous study found that the protective effects of bone marrow mesenchymal stem cells (BMSCs) in cerebral I/R injury may be associated with the regulation of autophagy. Recent studies have demonstrated that exosomes secreted from BMSCs (BMSC-Exos) may play an essential role in the effective biological performance of BMSCs and the protective mechanism of BMSC-Exos is associated with the activation of autophagy and the remission of inflammation, but it has not been reported in studies of cerebral I/R injury. We aimed to investigate the effects of BMSC-Exos on cerebral I/R injury and determine if the mechanism is associated with the regulation of pyroptosis and autophagic flux. Method: PC12 cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) to induce cerebral I/R in vitro and were cocultured with BMSC-Exos. Cell viability was determined with CCK-8 and lactate dehydrogenase (LDH) detection kits. Scanning electron microscopy (SEM), Hoechst 33342/propidium iodide (PI) double staining, 2',7'-dichlorodihydrofluorescein diacetate assay, immunofluorescence, Western blot, and Enzyme-linked immunosorbent assay (ELISA) were used to detect cell pyroptosis. Furthermore, transmission electron microscopy (TEM), GFP-RFP-LC3 adenovirus transfection, and Western blot were used to detect autophagic flux and its influence on pyroptosis. Finally, coimmunoprecipitation was used to detect the binding interaction between NLRP3 and LC3. Results: BMSC-Exos increased cell viability in OGD/R. The inhibitory effect of BMSC-Exos on pyroptosis was comparable to the NLRP3 inhibitor MCC950 and was reversed by NLRP3 overexpression. Furthermore, BMSC-Exos promoted autophagic flux through the AMP-activated kinase (AMPK)/mammalian target of the rapamycin pathway, whereas chloroquine, AMPK silencing, and compound C blocked the inhibitory effect on pyroptosis. Conclusions: BMSC-Exos can protect PC12 cells against OGD/R injury via attenuation of NLRP3 inflammasome-mediated pyroptosis by promoting AMPK-dependent autophagic flux.

Project description:BACKGROUND:The purpose of this study was to examine the relationships between glucose parameters obtained by continuous glucose monitoring and clinical outcomes in acute stroke patients. METHODS AND RESULTS:Consecutive patients with acute ischemic stroke or intracerebral hemorrhage within 24 hours after onset were included. A continuous glucose monitoring device (iPro2) was attached for the initial 72 hours after emergent admission. Eight glucose parameters were obtained from continuous glucose monitoring: maximum, minimum, mean, and SD of blood glucose levels, as well as area under the curve more than 8 mmol/L of blood glucose, distribution time more than 8 mmol/L of blood glucose, coefficient of variation (%CV), and presence of time less than 4 mmol/L over 72 hours. The primary outcome measure was death or dependency at 3 months (modified Rankin Scale score ?3). One hundred patients with acute ischemic stroke (n=58) or intracerebral hemorrhage (n=42) were included. Blood glucose levels varied between 5.2±1.4 and 11.4±3.2 mmol/L over 72 hours, with area under the curve more than 8 mmol/L of blood glucose of 0.7±1.4 min×mmol/L, distribution time more than 8 mmol/L of blood glucose of 31.7±32.7%, coefficient of variation of 15.5±5.4%, and presence of hypoglycemia in 20% of overall patients. Mean glucose level (adjusted odds ratio, 1.60, 95% confidence interval, 1.12-2.28/1 mmol/L), area under the curve more than 8 mmol/L of blood glucose (2.13, 1.12-4.02/1 min×mmol/L), and distribution time more than 8 mmol/L of blood glucose (1.25, 1.05-1.50/10%) were related to death or dependency for overall patients, as well as for acute ischemic stroke patients (2.05, 1.15-3.65; 2.38, 1.04-5.44; 1.85, 1.10-3.10, respectively). CONCLUSIONS:High mean glucose levels, distribution time more than 8 mmol/L of blood glucose, and areas under the curve more than 8 mmol/L of blood glucose during the initial 72 hours of acute stroke were associated with death or dependency at 3 months.

Dataset Information

Exosomes Secreted by the Cocultures of Normal and Oxygen-Glucose-Deprived Stem Cells Improve Post-stroke Outcome.

Publications

Exosomes Secreted by the Cocultures of Normal and Oxygen-Glucose-Deprived Stem Cells Improve Post-stroke Outcome.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets