scholarly journals Protective Effects ofN-Acetyl-L-Cysteine in Human Oligodendrocyte Progenitor Cells and Restoration of Motor Function in Neonatal Rats with Hypoxic-Ischemic Encephalopathy

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Dongsun Park ◽  
Kyungha Shin ◽  
Ehn-Kyoung Choi ◽  
Youngjin Choi ◽  
Ja-Young Jang ◽  
...  

Objective. Since oligodendrocyte progenitor cells (OPCs) are the target cells of neonatal hypoxic-ischemic encephalopathy (HIE), the present study was aimed at investigating the protective effects ofN-acetyl-L-cysteine (NAC), a well-known antioxidant and precursor of glutathione, in OPCs as well as in neonatal rats.Methods. Inin vitrostudy, protective effects of NAC on KCN cytotoxicity in F3.Olig2 OPCs were investigated via MTT assay and apoptotic signal analysis. Inin vivostudy, NAC was administered to rats with HIE induced by hypoxia-ischemia surgery at postnatal day 7, and their motor functions and white matter demyelination were analyzed.Results. NAC decreased KCN cytotoxicity in F3.Olig2 cells and especially suppressed apoptosis by regulating Bcl2 and p-ERK. Administration of NAC recovered motor functions such as the using ratio of forelimb contralateral to the injured brain, locomotor activity, and rotarod performance of neonatal HIE animals. It was also confirmed that NAC attenuated demyelination in the corpus callosum, a white matter region vulnerable to HIE.Conclusion. The results indicate that NAC exerts neuroprotective effectsin vitroandin vivoby preserving OPCs, via regulation of antiapoptotic signaling, and that F3.Olig2 human OPCs could be a good tool for screening of candidates for demyelinating diseases.

2021 ◽  
Author(s):  
Xiaojuan Su ◽  
Jun Tang ◽  
Lingyi Huang ◽  
Dongqiong Xiao ◽  
Xia Qiu ◽  
...  

Abstract BackgroundActivin A (Act A) has been revealed to enhance the differentiation of oligodendrocyte progenitor cells (OPCs) in vitro. Here we aim to elucidate its roles and mechanisms in a rat model of white matter injury (WMI). MethodsAct A was injected into the lateral ventricle of a hypoxia-ischemia induced WMI rat model. Hematoxylin & eosin staining was used to detect pathological changes. Immunofluorescence staining was used to assess OPC proliferation, migration, apoptosis, and differentiation. Myelin sheath and axon formation were detected via immunofluorescence staining, Western blotting, and electron microscopy. Behavioral assessment of rats was performed with the Morris water maze test. ResultsAct A attenuated the pathological damages, enhanced the formation of myelin sheath and myelinated axons and improved the behavior of WMI rats by promoting OPC proliferation and differentiation. However, Act A showed no significant effects on OPC migration or apoptosis. Interestingly, we found that Act A could enhance Noggin expression, which in turn inhibited the expression of bone morphogenetic protein 4 (BMP4) and inhibitor of DNA binding 2 (Id2). Furthermore, upregulation of Id2 completely abolished the protective effects of Act A in WMI. ConclusionsAct A improves WMI in neonatal rats via Noggin/BMP4/Id2 signalling.


2019 ◽  
Author(s):  
Jingling Li ◽  
Thomas Brickler ◽  
Allison Banuelos ◽  
Kristopher Marjon ◽  
Jing Bian ◽  
...  

AbstractOne of the most common genetic linkages associated with neuropsychiatric disorders, such as autism spectrum disorder and schizophrenia, occurs at the 16p11.2 locus. Copy number variants (CNVs) of the 16p gene can manifest in opposing head sizes. 16p11.2 deletion carriers tend to have macrocephaly (or brain enlargement), while those with 16p11.2 duplication frequently have microcephaly. Increases in both gray and white matter volume have been observed in brain imaging studies in 16p11.2 deletion carriers with macrocephaly. Here, we use human induced pluripotent stem cells (hiPSCs) derived from controls and subjects with 16p11.2 deletion and 16p11.2 duplication to understand the underlying mechanisms regulating brain overgrowth. To model both gray and white matter, we differentiated patient-derived iPSCs into neural progenitor cells (NPCs) and oligodendrocyte progenitor cells (OPCs). In both NPCs and OPCs, we show that CD47 (a ‘don’t eat me’ signal) is overexpressed in the 16p11.2 deletion carriers contributing to reduced phagocytosis both in vitro and in vivo. Treatment of 16p11.2 deletion NPCs and OPCs with an anti-CD47 antibody to block CD47 restores phagocytosis to control levels. Furthermore, 16p11.2 deletion NPCs and OPCs upregulate cell surface expression of calreticulin (a pro-phagocytic ‘eat me’ signal) and its binding sites, indicating that these cells should be phagocytosed but fail to be eliminated due to elevations in CD47. While the CD47 pathway is commonly implicated in cancer progression, we document a novel role for CD47 in regulating brain overgrowth in psychiatric disorders and identify new targets for therapeutic intervention.


2021 ◽  
Vol 118 (15) ◽  
pp. e2005483118 ◽  
Author(s):  
Jingling Li ◽  
Thomas Brickler ◽  
Allison Banuelos ◽  
Kristopher Marjon ◽  
Anna Shcherbina ◽  
...  

Copy number variation (CNV) at the 16p11.2 locus is associated with neuropsychiatric disorders, such as autism spectrum disorder and schizophrenia. CNVs of the 16p gene can manifest in opposing head sizes. Carriers of 16p11.2 deletion tend to have macrocephaly (or brain enlargement), while those with 16p11.2 duplication frequently have microcephaly. Increases in both gray and white matter volume have been observed in brain imaging studies in 16p11.2 deletion carriers with macrocephaly. Here, we use human induced pluripotent stem cells (hiPSCs) derived from controls and subjects with 16p11.2 deletion and 16p11.2 duplication to understand the underlying mechanisms regulating brain overgrowth. To model both gray and white matter, we differentiated patient-derived iPSCs into neural progenitor cells (NPCs) and oligodendrocyte progenitor cells (OPCs). In both NPCs and OPCs, we show that CD47 (a “don’t eat me” signal) is overexpressed in the 16p11.2 deletion carriers contributing to reduced phagocytosis both in vitro and in vivo. Furthermore, 16p11.2 deletion NPCs and OPCs up-regulate cell surface expression of calreticulin (a prophagocytic “eat me” signal) and its binding sites, indicating that these cells should be phagocytosed but fail to be eliminated due to elevations in CD47. Treatment of 16p11.2 deletion NPCs and OPCs with an anti-CD47 antibody to block CD47 restores phagocytosis to control levels. While the CD47 pathway is commonly implicated in cancer progression, we document a role for CD47 in psychiatric disorders associated with brain overgrowth.


Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Wanlong Pan ◽  
Xianshuang Liu ◽  
Xiaoming Zhang ◽  
Xinli Wang ◽  
Jiani Hu ◽  
...  

Background: Molecular mechanisms underlying stroke-induced neurogenesis have not been fully investigated. The microRNA 17-92 cluster (miR17-92) regulates proliferation and differentiation of adult neural progenitor cells (NPCs). The present study investigated whether the miR17-92 cluster in NPCs is required for stroke-induced neurogenesis. Methods and Results: Mice with inducible and conditional knockdown of the miR17-92 cluster in nestin lineage NPCs (nestin-CreER T2 /miR17-92 -/- , 17-92-cKO, n=9) and wild-type litters (WT, n=9) were treated by tamoxifen. Administration of tamoxifen resulted in more than 60% reduction of individual members of the miR-17-92 cluster (miR-17: 1.0 vs 0.4; miR-19a: 1.0 vs 0.3; miR-19b: 1.0 vs 0.2; miR-20a: 1.0 vs 0.4; miR-92a: 1.0 vs 0.4 fold in WT, p<0.05) in NPCs localized to the subventricular zone (SVZ). Two days after termination of tamoxifen treatment, these mice were subjected to permanent right middle cerebral artery occlusion (MCAO) and sacrificed 28 days post-MCAo. Compared to WT mice, 17-92-cKO mice exhibited significant (p<0.05) reduction of proliferation of NPCs measured by the number of Ki67 + cells (226±43 vs 471±100 cells/mm 2 ) and the number of DCX + neuroblasts (11±2% vs 24±4% ) in the ischemic SVZ. Cultured NPCs harvested from ischemic cKO mice showed significant (p<0.05) reduction of BrdU + cells (37±2% vs 61±4% WT , n=3/group), Tuj1 + neuroblasts (5±0.2% vs 9±0.4% ), GFAP + cells (33±3% vs 53±2% ), and NG2 + oligodendrocyte progenitor cells (OPCs, 3±0.1% vs 5±0.5%). These in vivo and in vitro data indicate that reduction of the miR17-92 cluster suppresses stroke-induced neurogenesis and gliogenesis. Western blot analysis showed that miR17-92 cKO significantly (p<0.05) increased and reduced a cytoskeleton-associated protein, Enigma homolog1 (ENH1, 1.6 vs 1.0 fold), and its down-stream transcription factor, inhibitor of differentiation1 (ID1, 1.0 vs 0.6 fold), respectively. ENH1 is a putative target of the miR17-92 cluster. Conclusion: Our data indicate that the miR17-92 cluster in adult nestin lineage NPCs is required for stroke-induced neurongenesis and gliogenesis, and that the miR17-92 cluster possibly targets ENH1/ID1 signaling.


2018 ◽  
Vol 8 (8) ◽  
pp. 147 ◽  
Author(s):  
Adam Edwards ◽  
Ryan Anderton ◽  
Neville Knuckey ◽  
Bruno Meloni

Perinatal hypoxic-ischemic encephalopathy (HIE) is the leading cause of mortality and morbidity in neonates, with survivors suffering significant neurological sequelae including cerebral palsy, epilepsy, intellectual disability and autism spectrum disorders. While hypothermia is used clinically to reduce neurological injury following HIE, it is only used for term infants (>36 weeks gestation) in tertiary hospitals and improves outcomes in only 30% of patients. For these reasons, a more effective and easily administrable pharmacological therapeutic agent, that can be used in combination with hypothermia or alone when hypothermia cannot be applied, is urgently needed to treat pre-term (≤36 weeks gestation) and term infants suffering HIE. Several recent studies have demonstrated that cationic arginine-rich peptides (CARPs), which include many cell-penetrating peptides [CPPs; e.g., transactivator of transcription (TAT) and poly-arginine-9 (R9; 9-mer of arginine)], possess intrinsic neuroprotective properties. For example, we have demonstrated that poly-arginine-18 (R18; 18-mer of arginine) and its D-enantiomer (R18D) are neuroprotective in vitro following neuronal excitotoxicity, and in vivo following perinatal hypoxia-ischemia (HI). In this paper, we review studies that have used CARPs and other peptides, including putative neuroprotective peptides fused to TAT, in animal models of perinatal HIE. We critically evaluate the evidence that supports our hypothesis that CARP neuroprotection is mediated by peptide arginine content and positive charge and that CARPs represent a novel potential therapeutic for HIE.


2019 ◽  
Author(s):  
C. Tigrine ◽  
A. Kameli

In this study a polyphenolic extract from Cleome arabica leaves (CALE) was investigated for its antioxidant activity in vitro using DPPH•, metal chelating and reducing power methods and for its protective effects against AraC-induced hematological toxicity in vivo using Balb C mice. Results indicated that CALE exhibited a strong and dose-dependent scavenging activity against the DPPH• free radical (IC50 = 4.88 μg/ml) and a high reducing power activity (EC50 = 4.85 μg/ml). Furthermore, it showed a good chelating effects against ferrous ions (IC50 = 377.75 μg/ml). The analysis of blood showed that subcutaneous injection of AraC (50 mg/kg) to mice during three consecutive days caused a significant myelosupression (P < 0.05). The combination of CALE and AraC protected blood cells from a veritable toxicity. Where, the number of the red cells, the amount of hemoglobin and the percentage of the hematocrite were significantly high. On the other hand, AraC cause an elevation of body temperature (39 °C) in mice. However, the temperature of the group treated with CALE and AraC remained normal and did not exceed 37.5 °C. The observed biological effects of CALE, in vitro as well as in vivo, could be due to the high polyphenol and flavonoid contents. In addition, the antioxidant activity of CALE suggested to be responsible for its hematoprotective effect.


2020 ◽  
Vol 18 ◽  
Author(s):  
Zirui Zhang ◽  
Shangcong Han ◽  
Panpan Liu ◽  
Xu Yang ◽  
Jing Han ◽  
...  

Background: Chronic inflammation and lack of angiogenesis are the important pathological mechanisms in deep tissue injury (DTI). Curcumin is a well-known anti-inflammatory and antioxidant agent. However, curcumin is unstable under acidic and alkaline conditions, and can be rapidly metabolized and excreted in the bile, which shortens its bioactivity and efficacy. Objective: This study aimed to prepare curcumin-loaded poly (lactic-co-glycolic acid) nanoparticles (CPNPs) and to elucidate the protective effects and underlying mechanisms of wound healing in DTI models. Methods: CPNPs were evaluated for particle size, biocompatibility, in vitro drug release and their effect on in vivo wound healing. Results : The results of in vivo wound closure analysis revealed that CPNP treatments significantly improved wound contraction rates (p<0.01) at a faster rate than other three treatment groups. H&E staining revealed that CPNP treatments resulted in complete epithelialization and thick granulation tissue formation, whereas control groups resulted in a lack of compact epithelialization and persistence of inflammatory cells within the wound sites. Quantitative real-time PCR analysis showed that treatment with CPNPs suppressed IL-6 and TNF-α mRNA expression, and up-regulated TGF-β, VEGF-A and IL-10 mRNA expression. Western blot analysis showed up-regulated protein expression of TGF-β, VEGF-A and phosphorylatedSTAT3. Conclusion: Our results showed that CPNPs enhanced wound healing in DTI models, through modulation of the JAK2/STAT3 signalling pathway and subsequent upregulation of pro-healing factors.


2019 ◽  
Vol 14 (4) ◽  
pp. 305-319 ◽  
Author(s):  
Marietta Herrmann ◽  
Franz Jakob

The bone marrow hosts skeletal progenitor cells which have most widely been referred to as Mesenchymal Stem or Stromal Cells (MSCs), a heterogeneous population of adult stem cells possessing the potential for self-renewal and multilineage differentiation. A consensus agreement on minimal criteria has been suggested to define MSCs in vitro, including adhesion to plastic, expression of typical surface markers and the ability to differentiate towards the adipogenic, osteogenic and chondrogenic lineages but they are critically discussed since the differentiation capability of cells could not always be confirmed by stringent assays in vivo. However, these in vitro characteristics have led to the notion that progenitor cell populations, similar to MSCs in bone marrow, reside in various tissues. MSCs are in the focus of numerous (pre)clinical studies on tissue regeneration and repair.Recent advances in terms of genetic animal models enabled a couple of studies targeting skeletal progenitor cells in vivo. Accordingly, different skeletal progenitor cell populations could be identified by the expression of surface markers including nestin and leptin receptor. While there are still issues with the identity of, and the overlap between different cell populations, these studies suggested that specific microenvironments, referred to as niches, host and maintain skeletal progenitor cells in the bone marrow. Dynamic mutual interactions through biological and physical cues between niche constituting cells and niche inhabitants control dormancy, symmetric and asymmetric cell division and lineage commitment. Niche constituting cells, inhabitant cells and their extracellular matrix are subject to influences of aging and disease e.g. via cellular modulators. Protective niches can be hijacked and abused by metastasizing tumor cells, and may even be adapted via mutual education. Here, we summarize the current knowledge on bone marrow skeletal progenitor cell niches in physiology and pathophysiology. We discuss the plasticity and dynamics of bone marrow niches as well as future perspectives of targeting niches for therapeutic strategies.


2021 ◽  
Vol 22 (3) ◽  
pp. 1390
Author(s):  
Julia Mester-Tonczar ◽  
Patrick Einzinger ◽  
Johannes Winkler ◽  
Nina Kastner ◽  
Andreas Spannbauer ◽  
...  

Circular RNAs (circRNAs) are crucial in gene regulatory networks and disease development, yet circRNA expression in myocardial infarction (MI) is poorly understood. Here, we harvested myocardium samples from domestic pigs 3 days after closed-chest reperfused MI or sham surgery. Cardiac circRNAs were identified by RNA-sequencing of rRNA-depleted RNA from infarcted and healthy myocardium tissue samples. Bioinformatics analysis was performed using the CIRIfull and KNIFE algorithms, and circRNAs identified with both algorithms were subjected to differential expression (DE) analysis and validation by qPCR. Circ-RCAN2 and circ-C12orf29 expressions were significantly downregulated in infarcted tissue compared to healthy pig heart. Sanger sequencing was performed to identify the backsplice junctions of circular transcripts. Finally, we compared the expressions of circ-C12orf29 and circ-RCAN2 between porcine cardiac progenitor cells (pCPCs) that were incubated in a hypoxia chamber for different time periods versus normoxic pCPCs. Circ-C12orf29 did not show significant DE in vitro, whereas circ-RCAN2 exhibited significant ischemia-time-dependent upregulation in hypoxic pCPCs. Overall, our results revealed novel cardiac circRNAs with DE patterns in pCPCs, and in infarcted and healthy myocardium. Circ-RCAN2 exhibited differential regulation by myocardial infarction in vivo and by hypoxia in vitro. These results will improve our understanding of circRNA regulation during acute MI.


Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 855
Author(s):  
Paola Serrano Martinez ◽  
Lorena Giuranno ◽  
Marc Vooijs ◽  
Robert P. Coppes

Radiotherapy is involved in the treatment of many cancers, but damage induced to the surrounding normal tissue is often inevitable. Evidence suggests that the maintenance of homeostasis and regeneration of the normal tissue is driven by specific adult tissue stem/progenitor cells. These tasks involve the input from several signaling pathways. Irradiation also targets these stem/progenitor cells, triggering a cellular response aimed at achieving tissue regeneration. Here we discuss the currently used in vitro and in vivo models and the involved specific tissue stem/progenitor cell signaling pathways to study the response to irradiation. The combination of the use of complex in vitro models that offer high in vivo resemblance and lineage tracing models, which address organ complexity constitute potential tools for the study of the stem/progenitor cellular response post-irradiation. The Notch, Wnt, Hippo, Hedgehog, and autophagy signaling pathways have been found as crucial for driving stem/progenitor radiation-induced tissue regeneration. We review how these signaling pathways drive the response of solid tissue-specific stem/progenitor cells to radiotherapy and the used models to address this.


Sign in / Sign up

Export Citation Format

Share Document