Conversion of Astrocyte Cell Lines to Oligodendrocyte Progenitor Cells Using Small Molecules and Transplantation to Animal Model of Multiple Sclerosis.

Astrocytes, the most prevalent cells in the central nervous system (CNS), can be transformed into neurons and oligodendrocyte progenitor cells (OPCs) using specific transcription factors and some chemicals. In this study, we present a cocktail of small molecules that target different signaling pathways to promote astrocyte conversion to OPCs. Astrocytes were transferred to an OPC medium and exposed for five days to a small molecule cocktail containing CHIR99021, Forskolin, Repsox, LDN, VPA and Thiazovivin before being preserved in the OPC medium for an additional 10 days. Once reaching the OPC morphology, induced cells underwent immunocytofluorescence evaluation for OPC markers while checked for lacking the astrocyte markers. To test the in vivo differentiation capabilities, induced OPCs were transplanted into demyelinated mice brains treated with cuprizone over 12 weeks. Two distinct lines of astrocytes demonstrated the potential of conversion to OPCs using this small molecule cocktail as verified by morphological changes and the expression of PDGFR and O4 markers as well as the terminal differentiation to oligodendrocytes expressing MBP. Following transplantation into demyelinated mice brains, induced OPCs effectively differentiated into mature oligodendrocytes. The generation of OPCs from astrocytes via a small molecule cocktail may provide a new avenue for producing required progenitors necessary for myelin repair in diseases characterized by the loss of myelin such as multiple sclerosis.

Targeted drug delivery into glial scar using CAQK peptide in a mouse model of multiple sclerosis.

In multiple sclerosis, lesions are formed in various areas of the CNS, which are characterized by reactive gliosis, immune cell infiltration, extracellular matrix changes and demyelination. CAQK peptide (peptide sequence: cysteine-alanine-glutamine-lysine) was previously introduced as a targeting peptide for the injured site of the brain. In the present study, we aimed to develop a multifunctional system using nanoparticles coated by CAQK peptide, to target the demyelinated lesions in animal model of multiple sclerosis. We investigated the binding of fluorescein amidite-labelled CAQK and fluorescein amidite-labelled CGGK (as control) on mouse brain sections. Then, the porous silicon nanoparticles were synthesized and coupled with fluorescein amidite-labelled CAQK. Five days after lysolecithin-induced demyelination, male mice were intravenously injected with methylprednisolone-loaded porous silicon nanoparticles conjugated to CAQK or the same amount of free methylprednisolone. Our results showed that fluorescein amidite-labelled CAQK recognizes demyelinated lesions in brain sections of animal brains injected with lysolecithin. In addition, intravenous application of methylprednisolone-loaded nanoparticle porous silicon conjugated to CAQK at a single dose of 0.24 mg reduced the levels of microglial activation and astrocyte reactivation in the lesions of mouse corpus callosum after 24 and 48 h. No significant effect was observed following the injection of the same dose of free methylprednisolone. CAQK seems a potential targeting peptide for delivering drugs or other biologically active chemicals/reagents to the CNS of patients with multiple sclerosis. Low-dose methylprednisolone in this targeted drug delivery system showed significant beneficial effect.

Saffron carotenoids reversed the UCMS-induced depression and anxiety in rats: Behavioral and biochemical parameters, and hippocampal BDNF/ERK/CREB and NR2B signaling markers.

BACKGROUND: Depression is a debilitating condition that affects the mind and the individual's body. The improving effects of saffron on depression and anxiety have long been discussed, with limited information about the molecular mechanism of action. HYPOTHESIS/PURPOSE: Investigating the effect of saffron carotenoids, Crocin and Crocetin, on depression and anxiety in rats by emphasizing some signaling pathways involved. STUDY DESIGN: Depression and anxiety were induced in rats via unpredictable chronic mild stress (UCMS). Then different rat groups were treated with Crocin, Crocetin, Fluoxetine, and vehicle. Behavioral tests were done before and after treatment. METHODS: The serum Serotonin and Corticosterone and the expression of some hippocampal signaling proteins were studied. Furthermore, bioinformatics tools were used to predict the interactions of Crocin/ Crocetin with the Serotonin transporter and NMDA receptor subunit NR2B. Then, the patch-clamp was used to study the interaction of Crocetin with the NMDA receptor. RESULTS: Various behavioral tests confirmed the induction of depression and the improvement of depression by these natural carotenoids. In addition, Crocin/ Crocetin significantly increased the decreased serum Serotonin and reduced the increased serum Corticosterone in the depressed groups. They also increased or caused a trend of increase in the CREB, ERK, BAD, BDNF, p11, and 5-HT1B expression in the hippocampus of the depressed groups. In addition, there were an increase or a trend in p-CREB/CREB, p-ERK1/2 /ERK1/2, and p-BAD/BAD ratios in the Crocin/ Crocetin treated depressed groups. However, the NR2B and FOXO3a expression showed a trend of decrease in depressed groups after treatment. The bioinformatics data indicated that Crocin/ Crocetin could bind to the Serotonin transporter (SLC6A4) and NR2B subunit of the NMDA receptor. Both carotenoids bind to the same site as Fluoxetine in the SLC6A4. However, they bound to different sites on the NR2B. So, Crocetin binds to NR2B at the same site as Ifenprodil. But Crocin bound to another site. The whole cell patch-clamp recording on the normal rat hippocampus revealed a significant decrease in the NMDA peak amplitude after Crocetin treatment, indicating its inhibitory effect on this receptor. CONCLUSION: The antidepressant activities of Crocin/ Crocetin are possibly due to their effects on Serotonin and Corticosterone serum concentrations, NR2B expression, and the downstream signaling pathways. Furthermore, these natural carotenoids, like Fluoxetine, induced an increasing tendency in p11 and 5HT1B in depressed rats.

Arbuscular mycorrhizal fungi and nitric oxide alleviate cadmium phytotoxicity by improving internal detoxification mechanisms of corn plants.

Plants develop several external and internal mechanisms to increase their tolerance to heavy metals (HMs) toxicity including cadmium (Cd). Symbiosis with arbuscular mycorrhizae fungi (AMF) is one of the plants' strategies to tolerate HMs toxicity. Nitric oxide (NO), as a signaling molecule, is also involved in physiological responses of plants to various stresses. The present work was conducted as a factorial completely randomized design with three replications to study the effects of Funneliformis mosseae fungi and Sodium nitroprusside (SNP, 100 mM) as a donor of NO alone, in combination (AMF + SNP) on corn plant growth, and internal detoxification mechanisms of Cd toxicity in a Cd-contaminated calcareous soil (0, 25, 50, and 100 mg Cd kg-1). The results showed that under Cd stress, AMF inoculation and/or foliar application of SNP significantly increased plant growth (32% to 103% for shoot and 44% to 84% for root) by decreasing Cd concentration in corn plant tissues (23% to 46% for shoot and 19% to 40% for root). Cd-induced oxidative stress was mitigated by AMF and/or SNP by enhancing the activities of antioxidant enzymes, including superoxide dismutase (SOD) and catalase (CAT), and concentration of non-enzymatic antioxidants such as glutathione (GSH) and phytochelatin (PC). Increasing the tolerance index (TI) and decreasing the transfer factor (TF) in the corn plants treated with AMF and/or SNP, confirm the efficient role of SNP and AMF in stimulating the detoxification mechanisms of Cd within the plant cells, which was more pronounced at the lowest Cd level (25 mg Cd kg-1). In conclusion, symbiotic associations of corn plants with AMF alone or in combination with SNP mitigated the detrimental effect of Cd toxicity in corn grown in Cd-contaminated calcareous soil. The corn's internal detoxification mechanisms lowered the Cd concentration in plant tissue which resulted in the improvement of the corn's growth parameters.

Erythropoietin Protects against Retinal Damage in A Rat Model of Optic Neuropathy via Glial Suppression.

OBJECTIVE: Traumatic optic neuropathy (TON) causes partial or complete blindness because death of irreplaceable retinal ganglion cells (RGCs). Neuroprotective functions of erythropoietin (EPO) in the nervous system have been considered by many studies investigating effectiveness of this cytokine in various retinal disease models. It has been found that changes in retinal neurons under conditions of glial cells are effective in vision loss, therefore, the present study hypothesized that EPO neuroprotective effect could be mediated through glial cells in TON model. MATERIALS AND METHODS: In this experiment study, 72 rats were assessed in the following groups: intact and optic nerve crush which received either the 4000 IU EPO or saline. Visual evoked potential and optomotor response and RGC number were assessed and regenerated axons evaluated by anterograde test. Cytokines gene expression changes were compared by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Density of astrocytes cells, assessed by fluorescence intensity, in addition, possible cytotoxic effect of EPO was measured on mouse astrocyte culture in vitro. RESULTS: in vitro data showed that EPO was not toxic for mouse astrocytes. Intravenous injection of EPO improved vision, in terms of visual behavioral tests. RGCs protection was more than two times in EPO, compared to the vehicle group. More regenerated axons were determined by anterograde tracing in the EPO group compared to the vehicle. Moreover, GFAP immunostaining showed while the intensity of reactive astrocytes was increased in injured retina, systemic EPO decreased it. In the treatment group, expression of GFAP was down-regulated, while CNTF was upregulated as assessed by qRT-PCR in the 60th day post-crush. CONCLUSION: Our study showed that systemic administration of EPO can protect degenerating RGCs. Indeed, exogenous EPO exerted neuroprotective and neurotrophic functions by reducing reactive astrocytic gliosis. Therefore, reduction of gliosis by EPO may be considered as therapeutic targets for TON.

Super-Tough PLA-Based Blends with Excellent Stiffness and Greatly Improved Thermal Resistance via Interphase Engineering.

Super-tough poly(lactic acid)/polycarbonate (PLA/PC) (50/50) blends with an excellent balance of stiffness, toughness, and thermal stability were systematically designed and characterized. Poly(methyl methacrylate) (PMMA) was utilized as a novel, highly effective nonreactive interphase to promote PLA-PC phase compatibility. Partial miscibility of PMMA with both PLA and PC produced strong molecular entanglements across the PLA-PC phase boundary followed by an excellent phase adhesion. This was predicted from interfacial energy measurements and supported by dynamic mechanical thermal analysis, morphological observations, and mechanical tests. Ternary PLA/PC/PMMA blends exhibited an exceptional set of stiffness, tensile and flexural strength, tensile and flexural ductility, and thermal stability together with improved impact strength compared with neat PLA and uncompatibilized PLA/PC blends. Addition of nonreactive polybutadiene-g-styrene-co-acrylonitrile (PB-g-SAN) impact modifier to the compatibilized blend resulted in further dramatic improvements in the dispersion state of PC and PMMA phase domains followed by the development of an interconnected structure of PC, PMMA, and PB-g-SAN domains in the PLA matrix. Such a network-like morphology, with rubbery particles percolated at the interface between the dispersed structures and surrounding PLA matrix, produced a tremendous increase in impact resistance (≈700 J/m) and tensile ductility (≈200% strain) while maintaining excellent stiffness (≥2.1 GPa). The combined effects of interfacial localization of impact modifier particles, network-like morphology (extended over the entire volume of the blend), and strong phase interactions between the components (due to mutual miscibility) are described to be responsible for super-tough behavior. The role of PMMA as an efficient interphase adhesion promoter in the toughened quaternary blends is also clarified. Impact fractography revealed multiple void formations, plastic growth of microvoids, and the formation of void-fibrillar structures around as well as inside the dispersed structures as the main micromechanical deformation processes responsible for massive shear yielding and plastic deformation of blends. Blends designed in this work offer remarkable improvements in tensile and flexural ductility, impact resistance, and heat deflection temperature compared with neat PLA resin. The overall characteristics of these blend systems are comparable and/or superior to those of several commercial thermoplastic resins.

Harmful compounds of soy milk: characterization and reduction strategies.

Soymilk is a plant based product which is a rich source of nutrients. However, various harmful compounds including allergens, anti-nutritional factors, and biogenic amines (BAs) exist in soybeans that may be transferred into soymilk. These compounds cause difficulties for consumers from mild to severe symptoms. Soymilk production is considered as a critical step in quantity of harmful compounds in final product. Common steps in soy milk manufacturing include soaking, grinding, and heating process. Allergens contents could be decreased by heating alone or in combination with structural modifiers and fermentation. BAs could be reduced by optimizing fermentation process and using suitable strains, especially BAs degradable types. Soaking, grinding and heating of soybeans in water are considered as effective methods for inactivation of antinutritional factors. Isoflavones are soy phytochemicals, which potentially leads to breast cancer in some women, can be converted to less bioavailable forms during processing. Other treatments such as high hydrostatic pressure and irradiation are also effective in harmful compounds reduction. Combination of the processes is more effective in harmful compounds removal. Considering the increasing trends in soymilk consumption, this review is focused on introduction of harmful compounds in soymilk and investigating the effects of processing condition on their concentration.

The impacts of salt reduction strategies on technological characteristics of wheat bread: a review.

Increased consumption of sodium is considered as the leading cause of cardiovascular disease and hypertension. Processed foods like bakery products are considered as the main source of sodium intake. Regarding the high consumption ratio of wheat bread, it is counted as the main contributor of sodium intake by the European food Safety Authorization and World Health Organization. Consequently, its salt reduction is considerably important to postpone adverse effects induced by sodium. Salt is used in wheat bread as a technological and sensory improver. Different salt reduction strategies (e.g. sodium free mineral salts, hollow salts, uneven salt distribution, amino acids and plant based salt boosters) had been assessed to reduce the sodium content in wheat bread. Despite their potential efficiency to partially imitate the technological and sensorial characteristics of salt in wheat breads, challenges also existed which may restrict their consumption level. Considering the importance of wheat bread in our daily diet, its high sodium content and the critical role of salt in its technological characteristics this study is aimed to review the influence of different salt reduction strategies in wheat bread from technological perspective.

Ursolic Acid Enhances Myelin Repair in Adult Mice Brains and Stimulates Exhausted Oligodendrocyte Progenitors to Remyelinate.

In multiple sclerosis patients, long-term inflammation makes the oligodendrocyte progenitor cells (OPCs) exhausted; therefore, a new therapy that makes them responsive to insults to participate in remyelination is highly in demand. Here, we investigated the effect of ursolic acid (UA) on myelin repair after mid-term and long-term demyelination periods induced by 6 or 12 weeks of cuprizone treatment followed by 2 weeks of recovery with or without UA. Immunohistochemistry studies and myelin genes expression assessment were used to evaluate the myelination status of mouse corpora callosa and the cellular mechanisms of myelin repair. Results showed that UA significantly promoted recovery from myelin loss after discontinuing 6 or 12 weeks of cuprizone feeding, as measured by luxol fast blue (LFB), fluoroMyelin (FM), anti-myelin basic protein (MBP) staining, and oligodendrocyte progenitor cell counts. It led to reduced inflammation and gliosis as evaluated by glial fibrillary acidic protein (GFAP), Iba1, or other marker gene transcripts. Following long-term demyelination, gliosis and TNF-α were observed as potential players in lesion pathology, which were restored by UA. An increased IL-10 may contribute to UA anti-inflammatory effect and making responsive the exhausted OPCs. UA increased the number of new oligodendrocyte lineage cells and myelination. Our findings indicated that UA can enhance myelin repair after cuprizone challenge through the prevention of gliosis and increasing the newly generated myelin.

Expression pattern and clinical significance of ß-catenin gene and protein in patients with primary malignant and benign bone tumors.

This study is aimed to unravel the status of local and circulating ß-catenin in different primary bone tumors and its relevance to tumor types, severity, and chemotherapy. The ß-catenin mRNA expression level and the expression of the protein (intensity level) were evaluated in tumor tissue and peripheral blood mononuclear cells of 150 patients with different types of primary bone tumors (78 malignant and 72 benign tumors) using Real-Time PCR and immunohistochemistry. The ß-catenin mRNA expression level and the expression of the protein were increased in bone tumors which was positively correlated with the tumor malignancy. Amongst osteosarcoma, Ewing's Sarcoma, chondrosarcoma, osteochondroma, Giant Cell Tumor, and exostosis tumors, the osteosarcoma, and Giant Cell Tumor groups showed the highest level of ß-catenin expression. The ß-catenin expression in malignant bone tumors was significantly correlated with tumor grade, size, metastasis, tumor recurrent, and the level of response to chemotherapy. A similar pattern of ß-catenin gene expression and its association with tumor characteristics was detected in the patient's peripheral blood cells. The simultaneous increase in the expression of the ß-catenin gene and protein in tumor tissue and in circulating blood cells and its relationship with tumor severity indicates the possible promoting role of ß-catenin in primary bone tumor pathogenesis.

Hotair and Malat1 Long Noncoding RNAs Regulate Bdnf Expression and Oligodendrocyte Precursor Cell Differentiation.

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophins family with well-known roles in neural development, differentiation, survival, and synaptic plasticity; however, it has not been explained thoroughly how the expression of this critical gene is regulated. To reveal some aspects of Bdnf gene regulation, here it was explored whether metastasis-associated lung adenocarcinoma transcript 1 (Malat1) and HOX transcript antisense RNA (Hotair) lncRNAs play roles in the regulation of Bdnf expression level, the effect of fingolimod treatment on downstream pathways, and oligodendrocyte precursor cell (OPC) maturation. First, in rat primary glial culture, the effect of Hotair and Malat1 was investigated on Bdnf expression using downregulation by specific DNAzymes. Then, immunostaining and RT-qPCR assays were employed to assess the functions of fingolimod and lncRNAs on OPC maturation. The results demonstrated that Bdnf was significantly correlated to Hotair and Malat1 lncRNAs in glial cells. Also, a strong correlation was observed between these two lncRNAs in glial culture and isolated OPCs. Fingolimod treatment coordinated lncRNAs' role on Bdnf expression in glial cells and enhanced OPC myelination three times compared to control. Furthermore, results suggested that Malat1 may have a role in the last stages of the intrinsic oligodendrocyte (OL) myelination regardless of fingolimod treatment. As BDNF is involved in brain development, survival, and functions, understanding the regulatory mechanism behind BDNF expression leads to a better comprehension of the pathogenesis of the neurodegenerative disorder and designing more effective treatments.

Long-Term Effects of Hippocampal Low-Frequency Stimulation on Pro-Inflammatory Factors and Astrocytes Activity in Kindled Rats.

OBJECTIVE: Epilepsy is accompanied by inflammation, and the anti-inflammatory agents may have anti-seizure effects. In this investigation, the effect of deep brain stimulation, as a potential therapeutic approach in epileptic patients, was investigated on seizure-induced inflammatory factors. MATERIALS AND METHODS: In the present experimental study, rats were kindled by chronic administration of pentylenetetrazol (PTZ; 34 mg/Kg). The animals were divided into intact, sham, low-frequency deep brain stimulation (LFS), kindled, and kindled +LFS groups. In kindled+LFS and LFS groups, animals received four trains of intra-hippocampal low-frequency deep brain stimulation (LFS) at 20 minutes, 6, 24, and 30 hours after the last PTZ injection. Each train of LFS contained 200 pulses at 1 Hz, 200 µA, and 0.1 ms pulse width. One week after the last PTZ injection, the Y-maze test was run, and then the rats' brains were removed, and hippocampal samples were extracted for molecular assessments. The gene expression of two pro-inflammatory factors [interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α)], and glial fibrillary acidic protein (GFAP) immunoreactivity (as a biological marker of astrocytes reactivation) were evaluated. RESULTS: Obtained results showed a significant increase in the expression of of interleukin-6 (IL-6), tumor necrosis factor (TNF)-α, and GFAP at one-week post kindling seizures. The application of LFS had a long-lasting effect and restored all of the measured changes toward normal values. These effects were gone along with the LFS improving the effect on working memory in kindled animals. CONCLUSION: The anti-inflammatory action of LFS may have a role in its long-lasting improving effects on seizure-induced cognitive disorders.

Dendrosomal nanocurcumin promotes remyelination through induction of oligodendrogenesis in experimental demyelination animal model.

Multiple sclerosis (MS) is an autoimmune disease, associated with central nervous system (CNS) inflammation, demyelination, and axonal loss. Myelin, a multilayer membranous that covers nerve fibers, is essential for rapid impulse conduction. Oligodendrocytes that are generated either from CNS-resident oligodendrocyte progenitor cells (OPCs) or subventricular zone-derived neural stem cells (NSCs) are the myelinating cells of the CNS. The adult CNS maintains a certain endogenous potential to repair myelin damage. However, this process often fails as MS progresses. The origin of this failure is not fully understood, but it is likely to relate to progenitors/stem cells' arrestment in a quiescent state, incapable of generating new oligodendrocyte. Current treatments for MS are immunomodulatory or immunosuppressive medications, with little to no effect on myelin restoration. Recent studies have provided proof-of-principle that CNS remyelination can be promoted either via enhancing endogenous remyelination or by transplanting myelinating cells. Curcumin, a natural polyphenolic compound, has been shown to have therapeutic properties in several neurodegenerative diseases. Here, we investigated the effect of a curcumin nanoformulation, dendrosomal nanoparticles (DNC) on oligodendrogenesis and remyelination, both in vitro and in animal model of demyelination. We indicated that DNC enhanced oligodendrogenesis from NSCs and OPCs, in vitro in dose dependent manner. DNC also induced in vivo remyelination via promotion of oligodendrogenesis. Furthermore, DNC enhanced remyelination capacity of transplanted NSCs through promoting their survival and oligodendrogenesis capacity. Our findings suggest that DNC has significant beneficial effects in demyelinating conditions, either as mono-therapy or as being paired with transplantation approaches.

Enhancing myelin repair in experimental model of multiple sclerosis using immobilized chondroitinase ABC I on porous silicon nanoparticles.

Removal of chondroitin sulfate proteoglycans (CSPGs) with chondroitinase ABC I (ChABC) facilitates axonal plasticity, axonal regeneration and remyelination, following injury to the central nervous system (CNS). However, the ChABC rapidly undergoes thermal inactivity and needs to be injected repeatedly. Here this limitation was overcame by immobilizing the ChABC on porous silicon (PSi) nanoparticles (ChABC@PSi). The efficacy of immobilized ChABC on CSPGs level and the demyelination insult was assessed in mice corpora callosa demyelinated by 6 weeks cuprizone (CPZ) feeding. ChABC@PSi was able to reduce the amount of CSPGs two weeks after animals treatment. CSPGs digestion by ChABC@PSi reduced the extent of demyelinated area as well as the astrogliosis. Furthermore, ChABC@PSi treatment increased the number of newly generated oligodendrocyte lineage cells which imply for enhanced myelin repair. Our results showed that effective CSPGs digestion by ChABC@PSi enhanced remyelination in CPZ model. Accordingly, ChABC@PSi may have a great potential to be used for treatment of diseases like multiple sclerosis and spinal cord injury by promoting the regeneration of damaged nerves.

Inhibition of Rho-kinase improves response to deep inspiration in ovalbumin-sensitized guinea pigs.

OBJECTIVES: The modulatory effect of deep inspiration (DI) on airway constriction is impaired in asthma. However, mechanisms underlying this impairment are not clear. Since there is evidence indicating that Rho-kinase activation mediates force maintenance under oscillatory strain, we investigated the impact of Rho-kinase inhibition on the bronchodilatory effect of DI in ovalbumin (OVA) sensitized guinea pigs. MATERIALS AND METHODS: forty-eight male Dunkin Hartley guinea pigs were divided into 8 groups including saline/ constant, saline/DI, OVA/constant, OVA/DI, Rho-I/OVA/constant, Rho-I/OVA/DI, OVA-Rho-I/MCh/constant, and OVA-Rho-I/MCh/DI. Animals were subjected to 12 inhalations of OVA or saline aerosol. Guinea pigs in Rho-I/OVA/constant or DI groups were treated with the Rho-kinase inhibitor (Rho-I) (Y-27632, 1 mM aerosols) prior to the last 8 allergen inhalations and OVA-Rho-I/MCh/constant or DI groups received Y-27632 at the end of allergen sensitization protocol before methacholine challenge. The bronchodilatory effect of DI in guinea pigs that were exposed to methacholine was assessed by using an animal ventilator. The bronchodilatory effect was assessed using several parameters: the airway pressure maintenance, airway pressure recovery, and decline of airway pressure. RESULTS: Results indicated that application of Y-27632 prior to methacholine challenge reduces the airway smooth muscle ability to maintain pressure and also causes further decline in airway pressure in OVA-sensitized animals undergone DI. However, the inhibition of Rho-kinase before OVA inhalations had minimal effect. CONCLUSION: We propose that alteration of Rho-kinase signaling pathway may be one of the mechanisms underlying the impairment of DI-induced bronchodilation in OVA-sensitized guinea pigs.

Protective Effects of a Nano-Formulation of Curcumin against Cuprizone-Induced Demyelination in the Mouse Corpus Callosum.

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS), characterized by neuroinflammation, oligodendrocytes (OLs) loss, and demyelination Curcumin, a natural phenolic substance, has been shown to have significant therapeutic properties in various neurodegenerative diseases, including MS. In our laboratory by loading curcumin in dendrosome nanoparticles we improved its solubility and bioavailability. Our previous study showed anti-inflammatory and anti-oxidative effects of dendrosomal nano-curcumin (DNC) in experimental autoimmune encephalomyelitis (EAE) model of MS. Here, by using a toxic demyelination model, induced by cuprizone (CPZ), we investigated the protective effect of DNC on oligodendroglial lineage cells (OLLC) and myelin preservation in context of acute demyelination. CPZ is a copper chelator, thus its intake reduces the mitochondrial activity, activates oxidative stress response, leading to specific OLs death, due to their high-energy consumption. We also evaluated DNC effect on activation of astrocytes and microglia, which are enriched in both MS and CPZ demyelinated lesions. Our results demonstrated that DNC treatment protected Oligodendrocyte lineage cells (OLLCs) against CPZ toxin. Besides DNC treatment suppressed accumulation of astrocytes and microglia in CC of CPZ-fed mice, compared to PBS treated onse. Moreover, DNC treatment lead to higher index of luxol fast bluefast blue (LFB) and myelin-specific proteins, myelin basic protein (MBP) intensity in the corpus callosum (CC), as indicators of myelin content. These results suggest a potent pleiotropic therapeutic efficiency for DNC for protection of myelinating cells, possibly via suppression of astrocytes and microglia.

Co-administration of aspirin and adipose-derived stem cell conditioned medium improves the functional recovery of the optic pathway in a lysolecithin-induced demyelination model.

INTRODUCTION: Based on beneficial effects of aspirin and mesenchymal stem cells (MSCs) on myelin repair, in a preset study, effects of co-administration of aspirin and conditioned medium from adipose tissue-derived stem cells (ADSC-CM) on functional recovery of optic pathway, demyelination levels, and astrocytes' activation were evaluated in a lysolecithin (LPC)-induced demyelination model of optic chiasm. METHODS: LPC (1%, 2 µL) was injected into the rat optic chiasm and animals underwent daily intraperitoneal (i.p.) injections of ADSCs-CM and oral gavage of aspirin at a dose of 25 mg/kg for 14 days post LPC injection. The conductivity of visual signals was assessed using visual evoked potential recordings (VEPs) before LPC injection and on days 7 and 14 post lesion. Immunostaining against PDGFRα as oligodendrocyte precursor cells marker, MOG as mature myelin marker, and GFAP as astrocyte marker was performed on brain sections at day 14 post LPC injection. FluoroMyelin staining was also used to measure the extent of demyelination areas. RESULTS: Our results showed that administration of ADSCs-CM and aspirin significantly reduced the latency of VEP waves in LPC receiving animals. In addition, demyelination levels and GFAP expressing cells were attenuated while the number of oligodendrocyte precursor cells significantly increased in rats treated with ADSCs-CM and aspirin. CONCLUSION: Overall, our results suggest that co-administration of ADSCs-CM and aspirin improves the functional recovery of optic pathway through amelioration of astrocyte activation and attenuation of demyelination level.

Fabrication and evaluation of novel quercetin-conjugated Fe3O4-ß-cyclodextrin nanoparticles for potential use in epilepsy disorder.

BACKGROUND: Despite the numerous pharmacological activities of quercetin, its biomedical application has been hampered, because of poor water solubility and low oral bioavailability. In the present study, we fabricated a novel form of quercetin-conjugated Fe3O4-ß-cyclodextrin (ßCD) nanoparticles (NPs), and the effect of these prepared NPs was evaluated in a chronic model of epilepsy. METHODS: Quercetin-loaded NPs were prepared using an iron oxide core coated with ßCD and pluronic F68 polymer. The chronic model of epilepsy was developed by intraperitoneal injection of pentylenetetrazole (PTZ) at dose of 36.5 mg/kg every second day. Quercetin or its nanoformulation at doses of 25 or 50 mg/kg were administered intraperitoneally 10 days before PTZ injections and their applications continued 1 hour before each PTZ injection. Immunostaining was performed to evaluate the neuronal density and astrocyte activation of hippocampi. RESULTS: Our data showed successful fabrication of quercetin onto Fe3O4-ßCD NPs. In comparison to free quercetin, quercetin NPs markedly reduced seizure behavior, neuronal loss, and astrocyte activation in a PTZ-induced kindling model. CONCLUSION: Overall, quercetin-Fe3O4-ßCD NPs might be regarded as an ideal therapeutic approach in epilepsy disorder.

Trichostatin A Promotes the Conversion of Astrocytes to Oligodendrocyte Progenitors in a Defined Culture Medium.

The generation of oligodendrocyte progenitor cells (OPCs) offers tremendous opportunities for cell replacement therapy in demyelinating diseases such as multiple sclerosis (MS) and spinal cord injury. Recently, the prospect of reprogramming terminally differentiated adult cells towards another mature somatic cell or progenitor cells without an intermediate pluripotent state has been of interest. Trichostatin A is a histone deacetylase inhibitor which opens the chromatin and facilitates the transcription of silence genes. In this study, we have treated human astrocytes line U87 and primary culture of mouse astrocytes with TSA for 12 h, prior their transfer to OPC induction medium. Then we evaluated the morphology and the fate of the treated astrocytes at post-treatment days. Both cell lines acquired OPC morphology and expressed OPC specific markers. Following transfer to differentiation medium, U87-derived iOPCs differentiated to oligodendrocyte like cells and expressed PLP as a mature oligodendrocyte marker. Our results introduced TSA as an inducer for production of OPCs from astrocytes and could be considered a potential way for the treatment of demyelinating diseases.