Survival Of Neural Stem Cells Research Articles

A Quantitative Proteomic Approach Explores the Possible Mechanisms by Which the Small Molecule Stemazole Promotes the Survival of Human Neural Stem Cells.

Neurodegenerative disorders have become a serious healthcare problem worldwide and there is no efficacious cure. However, regulating the fate of stem cells is an effective way to treat these neurological diseases. In previous work, stemazole was reported to maintain the survival of human neural stem cells in the absence of growth factors and to have therapeutic effects on neurodegenerative diseases. However, although it is a promising small molecule, the molecular mechanisms against apoptosis are ambiguous. In this study, tandem mass tag (TMT)-based proteomics were performed to obtain whole protein expression profiles of human neural stem cells in different groups under extreme conditions. Bioinformatics analysis based on protein–protein interaction (PPI) network construction, gene ontology (GO) and the Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment analysis were adopted to explore crucial proteins and possible pharmacological mechanisms. A total of 77 differentially expressed proteins were identified, comprising 38 upregulated proteins and 39 downregulated proteins. Combined with a diseases database of Alzheimer’s disease (AD), caspase-2 (CASP2), PKA C-alpha (PRKACA), fibronectin (FN1), large neutral amino acid transporter small subunit 1 (SLC7A5), which are involved in cell proliferation and apoptosis, this was further validated by enzyme activity assay and molecular docking, and regarded as putative targets regulated by stemazole. The present results give an insight into this small molecule and a better understanding for further elucidating the underlying mechanisms in the treatment of stem cells and neurodegenerative diseases.

Astrocytes Mediate Cholinergic Regulation of Adult Hippocampal Neurogenesis and Memory Through M1 Muscarinic Receptor

BackgroundIn the neurogenic niches of the adult hippocampus, new functional neurons are continuously generated throughout life, and generation of these neurons has been implicated in learning and memory. Astrocytes, as components of the neurogenic niches, are critical in the regulation of adult hippocampal neurogenesis (AHN). However, little is known about how astrocytes receive and respond to extrinsic cues to regulate AHN. MethodsBy using a transgenic strategy to conditionally delete astrocytic CRHM1 in mice and AAV (adeno-associated virus)–mediated overexpression of astrocytic CHRM1 specifically in the hippocampal dentate gyrus, we systematically investigated the role of astrocytic CHRM1 in the regulation of AHN and the underlying mechanisms using the combined approaches of immunohistochemistry, retrovirus labeling, electrophysiology, primary astrocyte cultures, immunoblotting, and behavioral assays. ResultsWe report that genetic ablation of CHRM1 in astrocytes led to defects in neural stem cell survival, neuronal differentiation, and maturation and integration of newborn neurons in the dentate gyrus. Astrocytic CHRM1-mediated modulation of AHN was mediated by BDNF (brain-derived neurotrophic factor) signaling. Furthermore, CHRM1 ablation in astrocytes impaired contextual fear memory. These impairments in both AHN and memory were rescued by overexpression of astrocytic CHRM1 in the dentate gyrus. ConclusionsOur findings reveal a critical role for astrocytes in mediating cholinergic regulation of AHN and memory through CHRM1.

Growth hormone-releasing hormone (GHRH) promotes survival and proliferation of neural stem cells and reduces amyloid-[beta]-induced toxicity

Growth hormone-releasing hormone (GHRH) promotes survival and proliferation of neural stem cells and reduces amyloid-[beta]-induced toxicity

The Neurodevelopmental Disorders Associated Gene Rnf113a Regulates Survival and Differentiation Properties of Neural Stem Cells.

RNF113A (Ring Finger Protein 113A) is genetically associated with autism spectrum disorders and X-linked trichothiodystrophy (TTD) syndrome. Loss-of-function mutations in human RNF113A are causally linked to TTD, which is characterized by abnormal development of the central nervous system (CNS) and mental retardation. How the loss of RNF113A activity affects brain development is not known. Here we identify Rnf113a1 as a critical regulator of cell death and neurogenesis during mouse brain development. Rnf113a1 gene exhibits widespread expression in the embryonic CNS. Knockdown studies in embryonic cortical neural stem/progenitor cells (NSCs) and the mouse cortex suggest that Rnf113a1 controls the survival, proliferation, and differentiation properties of progenitor cells. Importantly, Rnf113a1 deficiency triggers cell apoptosis via a combined action on essential regulators of cell survival, including p53, Nupr1, and Rad51. Collectively, these observations establish Rnf113a1 as a regulatory factor in CNS development and provide insights into its role in neurodevelopmental defects associated with TTD and autism.

Oleic acid is an endogenous ligand of TLX/NR2E1 that triggers hippocampal neurogenesis

Neural stem cells, the source of newborn neurons in the adult hippocampus, are intimately involved in learning and memory, mood, and stress response. Despite considerable progress in understanding the biology of neural stem cells and neurogenesis, regulating the neural stem cell population precisely has remained elusive because we have lacked the specific targets to stimulate their proliferation and neurogenesis. The orphan nuclear receptor TLX/NR2E1 governs neural stem and progenitor cell self-renewal and proliferation, but the precise mechanism by which it accomplishes this is not well understood because its endogenous ligand is not known. Here, we identify oleic acid (18:1ω9 monounsaturated fatty acid) as such a ligand. We first show that oleic acid is critical for neural stem cell survival. Next, we demonstrate that it binds to TLX to convert it from a transcriptional repressor to a transcriptional activator of cell-cycle and neurogenesis genes, which in turn increases neural stem cell mitotic activity and drives hippocampal neurogenesis in mice. Interestingly, oleic acid-activated TLX strongly up-regulates cell cycle genes while only modestly up-regulating neurogenic genes. We propose a model in which sufficient quantities of this endogenous ligand must bind to TLX to trigger the switch to proliferation and drive the progeny toward neuronal lineage. Oleic acid thus serves as a metabolic regulator of TLX activity that can be used to selectively target neural stem cells, paving the way for future therapeutic manipulations to counteract pathogenic impairments of neurogenesis.

Periostin attenuates oxygen and glucose deprivation-induced death of mouse neural stem cells via inhibition of p38 MAPK activation

Promoting neural stem cells (NSCs) survival in the harsh niche is essential to cell replacement therapy for various central nervous system diseases. As an integral component of the extracellular matrix, Periostin (POSTN) has been shown to protect various cell types from hypoxia-ischemia damage. This study aimed to investigate the neuroprotective effects of POSTN on NSCs injury induced by oxygen and glucose deprivation (OGD). Under challenge with OGD, cell viability significantly decreased in cultured mouse NSCs, and supplement POSTN rescued cell viability in a concentration-dependent manner, as shown by CCK-8. TUNEL and propidium iodide/Hoechst staining showed that POSTN pretreatment protected NSCs against OGD-induced apoptosis. Western blot assay demonstrated that POSTN pretreatment inhibited cleavage of caspase-3 and restored the balance of Bcl-2/Bax. And pretreatment with cilengitide (an inhibitor of POSTN receptors) abolished the protective effect of POSTN. Further investigation demonstrated that supplement POSTN inhibited phosphorylation of p38 in a concentration-dependent manner. Moreover, the neuroprotective effect of POSTN was hampered by anisomycin, an activator of p38. We conclude that POSTN pretreatment in cultured mouse NSCs mitigated OGD-induced cell death, and inhibition of the p38 MAPK pathway might be one of the underlying mechanisms. Our findings may provide a novel strategy for enhancing both endogenous and exogenous NSCs survival after ischemia and hypoxia injury.

Regulation of adult neurogenesis by the endocannabinoid-producing enzyme diacylglycerol lipase alpha (DAGLa)

The endocannabinoid system modulates adult hippocampal neurogenesis by promoting the proliferation and survival of neural stem and progenitor cells (NSPCs). This is demonstrated by the disruption of adult neurogenesis under two experimental conditions: (1) NSPC-specific deletion of cannabinoid receptors and (2) constitutive deletion of the enzyme diacylglycerol lipase alpha (DAGLa) which produces the endocannabinoid 2-arachidonoylglycerol (2-AG). However, the specific cell types producing 2-AG relevant to neurogenesis remain unknown. Here we sought to identify the cellular source of endocannabinoids in the subgranular zone of the dentate gyrus (DG) in hippocampus, an important neurogenic niche. For this purpose, we used two complementary Cre-deleter mouse strains to delete Dagla either in neurons, or in astroglia and NSPCs. Surprisingly, neurogenesis was not altered in mice bearing a deletion of Dagla in neurons (Syn-Dagla KO), although neurons are the main source for the endocannabinoids in the brain. In contrast, a specific inducible deletion of Dagla in NPSCs and astrocytes (GLAST-CreERT2-Dagla KO) resulted in a strongly impaired neurogenesis with a 50% decrease in proliferation of newborn cells. These results identify Dagla in NSPCs in the DG or in astrocytes as a prominent regulator of adult hippocampal neurogenesis. We also show a reduction of Daglb expression in GLAST-CreERT2-Dagla KO mice, which may have contributed to the neurogenesis phenotype.

A three-dimensional matrix system containing melatonin and neural stem cells repairs damage from traumatic brain injury in rats.

Brain lesions can cause neural stem cells to activate, proliferate, differentiate, and migrate to the injured area. However, after traumatic brain injury, brain tissue defects and microenvironment changes greatly affect the survival and growth of neural stem cells; the resulting reduction in the number of neural stem cells impedes effective repair of the injured area. Melatonin can promote the survival, proliferation, and differentiation of neural stem cells under adverse conditions such as oxidative stress or hypoxia that can occur after traumatic brain injury. Therefore, we investigated the therapeutic effects of melatonin combined with neural stem cells on traumatic brain injury in rats. First, in vitro studies confirmed that melatonin promoted the survival of neural stem cells deprived of oxygen and glucose. Then, we established a three-dimensional Matrigel-based transplantation system containing melatonin and neural stem cells and then used it to treat traumatic brain injury in rats. We found that treatment with the Matrigel system containing melatonin and neural stem cells decreased brain lesion volume, increased the number of surviving neurons, and improved recovery of neurological function compared with treatment with Matrigel alone, neural stem cells alone, Matrigel and neural stem cells combined, and Matrigel and melatonin combined. Our findings suggest that the three-dimensional Matrigel-based transplantation system containing melatonin and neural stem cells is a potential treatment for traumatic brain injury.

A Multi-Ingredient Nutritional Supplement Exerts Antiapoptotic and Proliferative Effects on Rat Neural Stem Cells: A Novel Therapeutic Option

Background: The importance of neural stem cell (NSC) survival in the appropriate brain function, synapsis formation, and neural cell communication is to the degree that any perturbation in this process leads to many neurodegenerative diseases. Numerous therapeutic approaches have recently been developed to prolong the survival of NSCs, so that these multipotent stem cells could differentiate into other neural cells and improve the function of the brain. Methods: In this study, we aimed to investigate whether the treatment of isolated NSCs from the Wistar rats with the nutrition bio-shield (NBS) supplement could boost the survival of NSCs. Results: Of note, we found that the extract had negative effects neither on the biochemical and hematological parameters nor on the morphology of hepatocytes of the rats, suggestive of the lack of toxicity of the extract. Our results also suggested that the extract robustly increased the survival and the proliferative capacity of NSCs by elevating the metabolic activity of the cells. The NBS supplement also prevented the induction of apoptotic cell death in NSCs, as revealed by the decrease in the number of terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)-positive cells as compared to the control group. Conclusion: Overall, this study highlighted the potent efficacy of the NBS supplement in prolonging the survival of NSCs and proposed the possibility of the clinical use of the extract in the treatment of different neural diseases. However, further investigations in this field are required to provide the extract’s mechanism of action.

Reducing host aldose reductase activity promotes neuronal differentiation of transplanted neural stem cells at spinal cord injury sites and facilitates locomotion recovery.

Neural stem cell (NSC) transplantation is a promising strategy for replacing lost neurons following spinal cord injury. However, the survival and differentiation of transplanted NSCs is limited, possibly owing to the neurotoxic inflammatory microenvironment. Because of the important role of glucose metabolism in M1/M2 polarization of microglia/macrophages, we hypothesized that altering the phenotype of microglia/macrophages by regulating the activity of aldose reductase (AR), a key enzyme in the polyol pathway of glucose metabolism, would provide a more beneficial microenvironment for NSC survival and differentiation. Here, we reveal that inhibition of host AR promoted the polarization of microglia/macrophages toward the M2 phenotype in lesioned spinal cord injuries. M2 macrophages promoted the differentiation of NSCs into neurons in vitro. Transplantation of NSCs into injured spinal cords either deficient in AR or treated with the AR inhibitor sorbinil promoted the survival and neuronal differentiation of NSCs at the injured spinal cord site and contributed to locomotor functional recovery. Our findings suggest that inhibition of host AR activity is beneficial in enhancing the survival and neuronal differentiation of transplanted NSCs and shows potential as a treatment of spinal cord injury.

The Regulatory Effects of Taurine on Neurogenesis and Apoptosis of Neural Stem Cells in the Hippocampus of Rats.

The promotion of neurogenesis from neural stem cells (NSCs) in the hippocampus was found to be the most fundamental and effective therapy for depression. Our previous studies proved an antidepressive effect of taurine on rats, but the exact mechanism remains unclear. In this study, CUMS model was established in rats, and NSCs were cultured in vitro to investigate the protective effect and mechanisms of taurine on neurogenesis and apoptosis in CUMS rats and glutamate-injured NSCs. The results showed that ki67-positive cells were significantly increased by taurine, while apoptosis in the DG of CUMS rats was significantly inhibited by taurine. In vitro study, cell viability, Brdu+, β-tubulin III+, and GFAP+ cells in taurine-treated cells were significantly higher, while apoptosis rate was lower than the glutamate-treated cells. The protein expression of BDNF and its downstream pathway was upregulated by taurine administration. The results demonstrated that taurine can increase the survival, proliferation, and differentiation of NSCs; this protective effect of taurine may be due to the upregulation of BDNF/ERK/CREB signaling pathway. On the other hand, taurine can also inhibit abnormal apoptosis induced by CUMS or glutamate, the mechanism of which may be due to its antioxidative ability.

Trehalose and carnosic acid induced LC3I, LC3II ratio, P62 down-regulation and cleaved caspase 3 expression in neural stem cells.

Using neural stem cells (NSCs) in cell therapy and regenerative medicine is a growing knowledge. In this study, the protective role of carnosic acid and trehalose against H2O2-induced oxidative stress in autophagy induction and apoptosis inhibition in NSCs was investigated. The bone marrow stromal cells (BMSCs) were isolated from the femur of the rat and differentiated into NSCs using basic fibroblast and epidermal growth factors (bFGF and EGF), and B27 serum free media. To evaluate the autophagy, the P62 protein was assessed by immunocytochemistry and LC3II / LC3I ratio by Western blotting. Further, we used 3-Methyladenine (3-MA), a widely used autophagy inhibitor to study whether combined treatment of 3-MA with carnosic acid and trehalose modulates autophagy in NSCs. For studying apoptosis, the cleaved caspase-3 protein was evaluated. Carnosic acid and trehalose increased the survival of the NSCs. The H2O2 decreased the autophagy and induced apoptosis with increasing time during 24 hours, however, a pre-treatment with 2 μM carnosic acid and trehalose 3 % induced the autophagy proteins (while increasing the LC3II / LC3I ratio and decreasing the P62) and decreased the apoptosis (while decreasing the expression of the cleaved caspase-3). The results showed that the carnosic acid and trehalose increased the survival of NSCs against the oxidative stress caused by H2O2, decreased apoptosis, and induced autophagy. Due to the carnosic acid and trehalose unique properties and its low toxicity, it can be used as an agent in cellular transplantation for reducing oxidative stress and inducing autophagy (Fig. 4, Ref. 37).

The MAP Kinase Phosphatase MKP-1 Modulates Neurogenesis via Effects on BNIP3 and Autophagy.

Inherited and acquired defects in neurogenesis contribute to neurodevelopmental disorders, dysfunctional neural plasticity, and may underlie pathology in a range of neurodegenerative conditions. Mitogen-activated protein kinases (MAPKs) regulate the proliferation, survival, and differentiation of neural stem cells. While the balance between MAPKs and the family of MAPK dual-specificity phosphatases (DUSPs) regulates axon branching and synaptic plasticity, the specific role that DUSPs play in neurogenesis remains unexplored. In the current study, we asked whether the canonical DUSP, MAP Kinase Phosphatase-1 (MKP-1), influences neural stem cell differentiation and the extent to which DUSP-dependent autophagy is operational in this context. Under basal conditions, Mkp-1 knockout mice generated fewer doublecortin (DCX) positive neurons within the dentate gyrus (DG) characterized by the accumulation of LC3 puncta. Analyses of wild-type neural stem cell (NSC) differentiation in vitro revealed increased Mkp-1 mRNA expression during the initial 24-h period. Notably, Mkp-1 KO NSC differentiation produced fewer Tuj1-positive neurons and was associated with increased expression of the BCL2/adenovirus E1B 19-kD protein-interacting protein 3 (BNIP3) and levels of autophagy. Conversely, Bnip3 knockdown in differentiated Mkp-1 KO NSCs reduced levels of autophagy and increased neuronal yields. These results indicate that MKP-1 exerts a pro-neurogenic bias during a critical window in NSC differentiation by regulating BNIP3 and basal autophagy levels.

Schisandrin A and B affect the proliferation and differentiation of neural stem cells

Schisandrin A and B (Sch A and B) are the important components of Asian dietary supplement and phytomedicine Schisandra chinensis (S. chinensis). They can enhance adult neurogenesis in vivo; however, these effects still need to be verified. Here NE-4 C neural stem cells (NSCs) were employed as the in vitro model and treated with Sch A and B at 0.1 μg/mL. EdU (5-Ethynyl-2′-deoxyuridine) labeling showed that both Sch A and B treatments enhanced NSC proliferation. Real-time PCR analysis showed the mRNA abundances of telomerase gene Tert and cell cycle gene Cyclin D1 were significantly up-regulated after the treatments. During the neurosphere induction, Sch B enhanced the neurosphere formation and neuronal differentiation, and increased the neurosphere semidiameters. Detection of the neuron differentiation marker Mapt indicates that both Sch A and B, especially Sch B, benefits the induced neuronal differentiation. Sch B treatment also enhanced mRNA expressions of the neurosphere-specific adhesion molecule Cdh2 and Wnt pathway-related genes including Mmp9, Cyclin D1 and β-catenin. Together, Sch A especially Sch B, promotes the proliferation, affects the survival, differentiation and neurogenesis of NSCs, which is consistent with their in vivo effects. This study provides further clue on the potential neuropharmacological effects of S. chinensis.

Improved Survival and Regeneration of Irradiated Mouse Neural Stem Cells after Co-Culturing with Non-Irradiated Mouse Neural Stem Cells or Mesenchymal Stem Cells from the Adipose Tissue.

We studied the effect of neural stem cells (NSC) and mesenchymal stem cells (MSC) from mouse adipose tissue on survival, clonogenic activity, and senescence of NSC after exposure to γ-radiation. It was found that survival and clonogenic activity of NSC irradiated in doses of 1 and 2 Gy was enhanced when irradiated cells were co-cultured with non-irradiated NSC and MSC in permeable Transwell inserts. The proportion of senescent NSC (cells with high β-galactosidase activity) increased with increasing irradiation dose. Co-culturing with non-irradiated NSC in 3 days after irradiation in a dose of 1 Gy led to a decrease in the proportion of senescent cells among irradiated NSC. Factors secreted by NSC and MSC can become the basis for the development of means for prevention and treatment of damage to brain cells resulting from radiation therapy of head and neck cancer.

BMP-6 Attenuates Oxygen and Glucose Deprivation-Induced Apoptosis in Human Neural Stem Cells through Inhibiting p38 MAPK Signaling Pathway

Background and ObjectivesNeural stem cells (NSCs) remain in the mammalian brain throughout life and provide a novel therapeutic strategy for central nervous system (CNS) injury. Bone morphogenetic protein-6 (BMP-6) had shown a protective effect in different types of cells. However, the role of BMP-6 in NSCs is largely unclear. The present study was aimed to investigate whether BMP-6 could protect human NSCs (hNSCs) against the oxygen and glucose deprivation (OGD)-induced cell death.Methods and ResultsUpon challenge with OGD treatment, cell viability was significantly decreased in a time-dependent manner, as indicated by the CCK-8 assay. BMP-6 could attenuate the OGD-induced cell injury in a dose-dependent manner and decrease the number of TUNEL-positive cells. Moreover, BMP-6 markedly weakened the OGD-induced alterations in the expression of procaspase-8/9/3 and reversed the expression of cleaved-caspase-3. Interestingly, noggin protein (the BMP-6 inhibitor) attenuated the neuroprotective effect of BMP-6 in cultured hNSCs. Furthermore, the p38 MAPK signaling pathway was activated by OGD treatment and BMP-6 markedly inhibited the phosphorylation of p38 in a concentration-dependent manner. Pretreatment with noggin abolished the effect of BMP-6 on p38 activation. SB239063, a selective p38 inhibitor, exerted similar effects with BMP-6 in protecting hNSCs against the OGD-induced apoptosis. These results indicated that blocking the phosphorylation of p38 might contribute to the neuroprotective effect of BMP-6 against the OGD-induced injury in hNSCs.ConclusionsThese findings suggested that BMP-6 might be a therapeutic target in the OGD-induced cell death, which provides a novel therapeutic strategy for enhancing host and graft NSCs survival in hypoxic-ischemic brain injury.

Neural stem cell treatment for perinatal brain injury: A systematic review and meta-analysis of preclinical studies.

Perinatal brain injury can lead to significant neurological and cognitive deficits and currently no therapies can regenerate the damaged brain. Neural stem cells (NSCs) have the potential to engraft and regenerate damaged brain tissue. The aim of this systematic review was to evaluate the preclinical literature to determine whether NSC administration is more effective than controls in decreasing perinatal brain injury. Controlled interventional studies of NSC therapy using animal models of perinatal brain injury were identified using MEDLINE and Embase. Primary outcomes were brain infarct size, motor, and cognitive function. Data for meta‐analysis were synthesized and expressed as standardized mean difference (SMD) with 95% confidence intervals (CI), using a random effects model. We also reported secondary outcomes including NSC survival, migration, differentiation, and effect on neuroinflammation. Eighteen studies met inclusion criteria. NSC administration decreased infarct size (SMD 1.09; CI: 0.44, 1.74, P = .001; I 2 = 74%) improved motor function measured via the impaired forelimb preference test (SMD 2.27; CI: 0.85, 3.69, P = .002; I 2 = 86%) and the rotarod test (SMD 1.88; CI: 0.09, 3.67, P = .04; I 2 = 95%). Additionally, NSCs improved cognitive function measured via the Morris water maze test (SMD of 2.41; CI: 1.16, 3.66, P = .0002; I 2 = 81%). Preclinical evidence suggests that NSC therapy is promising for the treatment of perinatal brain injury. We have identified key knowledge gaps, including the lack of large animal studies and uncertainty regarding the necessity of immunosuppression for NSC transplantation in neonates. These knowledge gaps should be addressed before NSC treatment can effectively progress to clinical trial.

Gastrodin promotes hippocampal neurogenesis via PDE9-cGMP-PKG pathway in mice following cerebral ischemia

Gastrodin, which is extracted from the Chinese herbal medicine Gastrodia elata Blume, can ameliorate neurogenesis after cerebral ischemia. However, it's possible underlying mechanisms remain still elusive. PDE9-cGMP-PKG signaling pathway is involved in the proliferation of neural stem cells (NSCs) after cerebral ischemia. In this study, we investigated whether the beneficial effect of gastrodin on hippocampal neurogenesis after cerebral ischemia is correlated with the PDE9-cGMP-PKG signaling pathway. Bilateral common carotid artery occlusion (BCCAO) in mice and oxygen-glucose deprivation/reoxygenation (OGD/R) in primary cultured hippocampal NSCs were used to mimic brain ischemic injury. The Morris water maze (MWM) test was executed to detect spatial learning and memory. Proliferation, differentiation, and mature neurons were examined using immunofluorescence. The survival and proliferation of NSCs were assessed by CCK-8 assay and BrdU immunofluorescence staining, respectively. ELISA and western blot were used to detect the level of the PDE9-cGMP-PKG signaling pathway. In BCCAO mice, administering gastrodin (50 and 100 mg/kg) for 14 d restored cognitive behaviors; meanwhile, neurogenesis in hippocampus was stimulated, and PDE9 was inhibited and cGMP-PKG was activated by gastrodin. Consistent with the results, administering gastrodin (from 0.01–1 μmol/L) for 48 h dose-dependently ameliorated the cell viability and promoted greatly the proliferation in primary hippocampal NSCs exposed to OGD/R. Gastrodin further decreased PDE9 activity and up-regulated cGMP-PKG level. KT5823, a PKG inhibitor, markedly abrogated the protective effects of gastrodin on OGD/R-injured NSCs, accompanied by the down-regulation of PKG protein expression, but had no effects on PDE9 activity and cGMP level. Gastrodin could accelerate hippocampal neurogenesis after cerebral ischemia, which is mediated, at least partly, by PDE9-cGMP-PKG signaling pathway.

A novel RIP1/RIP3 dual inhibitor promoted OPC survival and myelination in a rat neonatal white matter injury model with hOPC graft

BackgroundThe dual inhibitors of receptor interacting protein kinase-1 and -3 (RIP1 and RIP3) play an important role in cell death processes and inflammatory responses. White matter injury (WMI), a leading cause of neurodevelopmental disabilities in preterm infants, which is characterized by extensive myelination disturbances and demyelination. Neuroinflammation, leads to the loss and differentiation-inhibition of oligodendrocyte precursor cells (OPCs), represents a major barrier to myelin repair. Whether the novel RIP1/RIP3 dual inhibitor ZJU-37 can promote transplanted OPCs derived from human neural stem cells (hOPCs) survival, differentiation and myelination remains unclear. In this study, we investigated the effect of ZJU-37 on myelination and neurobehavioral function in a neonatal rat WMI model induced by hypoxia and ischemia.MethodsIn vivo, P3 rat pups were subjected to right common carotid artery ligation and hypoxia, and then treated with ZJU-37 or/and hOPCs, then OPCs apoptosis, myelination, glial cell and NLRP3 inflammasome activation together with cognitive outcome were evaluated at 12 weeks after transplantation. In vitro, the effect of ZJU-37 on NLRP3 inflammasome activation in astrocytes induced by oxygen–glucose deprivation (OGD) were examined by western blot and immunofluorescence. The effect of ZJU-37 on OPCs apoptosis induced by the conditioned medium from OGD-injured astrocytes (OGD-astrocyte-CM) was analyzed by flow cytometry and immunofluorescence.ResultsZJU-37 combined with hOPCs more effectively decreased OPC apoptosis, promoted myelination in the corpus callosum and improved behavioral function compared to ZJU-37 or hOPCs treatment. In addition, the activation of glial cells and NLRP3 inflammasome was reduced by ZJU-37 or/and hOPCs treatment in the neonatal rat WMI model. In vitro, it was also confirmed that ZJU-37 can suppress NLRP3 inflammasome activation in astrocytes induced by OGD. Not only that, the OGD-astrocyte-CM treated with ZJU-37 obviously attenuated OPC apoptosis and dysdifferentiation caused by the OGD-astrocyte-CM.ConclusionsThe novel RIP1/RIP3 dual inhibitor ZJU-37 may promote OPC survival, differentiation and myelination by inhibiting NLRP3 inflammasome activation in a neonatal rat model of WMI with hOPC graft.

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature