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.

Repeated Morphine Exposure Alters Temporoamonic-CA1 Synaptic Plasticity in Male Rat Hippocampus.

In this study, the electrophysiological and biochemical consequences of repeated exposure to morphine in male rats on glutamatergic synaptic transmission, synaptic plasticity, the expression of GABA receptors and glutamate receptors at the temporoammonic-CA1 synapse along the longitudinal axis of the hippocampus (dorsal, intermediate, ventral, DH, IH, VH, respectively) were investigated. Slice electrophysiological methods, qRT-PCR, and western blotting techniques were used to characterize synaptic plasticity properties. We showed that repeated morphine exposure (RME) reduced excitatory synaptic transmission and ability for long-term potentiation (LTP) in the VH as well as eliminated the dorsoventral difference in paired-pulse responses. A decreased expression of NR2B subunit in the VH and an increased expression GABAA receptor of α1 and α5 subunits in the DH were observed following RME. Furthermore, RME did not affect the expression of NR2A, AMPA receptor subunits, and γ2GABAA and GABAB receptors in either segment of the hippocampus. In sum, the impact of morphine may differ depending on the region of the hippocampus studied. A distinct change in the short- and long-term synaptic plasticity along the hippocampus long axis due to repeated morphine exposure, partially mediated by a change in the expression profile of glutamatergic receptor subunits. These findings can be useful in further understanding the cellular mechanism underlying deficits in information storage and, more generally, cognitive processes resulting from chronic opioid abuse.

Avoidance and escape conditioning adjust adult neurogenesis to conserve a fit hippocampus in adult male rodents.

In this study, the connection between cognitive behaviors and the adult rodent hippocampus was investigated. Recording field potentials at performant pathway (PP)-hippocampal dentate gyrus (DG) synapses in transverse slices from the dorsal (d), intermediate (i), and ventral (v) hippocampus showed differences in paired-pulse responses and long-term potentiation in rats. The Barnes maze (BM) and passive avoidance (PA) tests indicated a decrease in escape latency and step-through latency in both rats and mice over training days. A decrease in the use of random or sequential strategy while an increase in the use of direct strategy to search for an escape box occurred in both groups. Evaluation of the levels of neurogenesis markers (Ki67 and BrdU/NeuN) by immunofluorescence assay in the dDG, iDG, and vDG revealed a long-axis disparity in the hippocampal dentate baseline cell proliferation and exposure to the BM and PA task changed the profile of baseline cell proliferation along the DG in both rats and mice. Also, these learning experiences changed the profile of BrdU+ /NeuN+ cells along the DG of rats. Quantitation of hippocampal BDNF protein levels using ELISA exhibited no changes in BDNF levels due to learning experiences in rats. We demonstrate that PP-DG synaptic efficacy and neurogenesis are organized along a gradient. Avoidance and escape conditioning themselves are sufficient to change and calibrate adult neurogenesis along the hippocampal long axis in rodents. Further research will be required to determine the precise mechanisms underlying the role of experience-derived neuroplasticity in cognitive function and decline.

siRNA-Mediated B7H7 Knockdown in Gastric Cancer Lysate-Loaded Dendritic Cells Amplifies Expansion and Cytokine Secretion of Autologous T Cells.

BACKGROUND: Gastric cancer, ranked as the fifth most common cancer worldwide, presents multiple treatment challenges. These obstacles often arise due to cancer stem cells, which are associated with recurrence, metastasis, and drug resistance. While dendritic cell (DC)-based immunotherapy has shown promise as a therapeutic strategy, its efficacy can be limited by the tumor microenvironment and certain inhibitory immune checkpoint molecules, such as B7H7. SiRNA-medicated knockdown of B7H7 in tumor cell lysate-pulsed DCs can increase cytokine secretion and autologous T lymphocyte expansion. This study aimed to evaluate the impact of B7H7 suppression in gastric cancer cell lysate-pulsed DCs on the stimulatory potential of autologous CD3+ T lymphocytes. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated and monocytes were obtained; then, they were differentiated to immature DCs (iDCs) by GM-CSF and IL-4. Tumor cell lysates from human gastric cancer cell lines were harvested, and iDCs were transformed into mature DCs (mDCs) by stimulating iDCs with tumor cell lysate and lipopolysaccharide. B7H7-siRNA was delivered into mDCs using electroporation, and gene silencing efficiency was assessed. The phenotypic characteristics of iDCs, mDCs, and B7H7-silenced mDCs were evaluated using specific surface markers, an inverted light microscope, and flow cytometry. CD3+ T cells were isolated via magnetically activated cell sorting. They were labeled with CFSE dye and co-cultured with mDCs and B7H7-silenced mDCs to evaluate their ability to induce T-cell proliferation. T-cell proliferation was assessed using flow cytometry. The concentration of TGF-ß, IL-4, and IFN-γ secreted from CD3+ T cells in the co-cultured supernatant was evaluated to investigate the cytokine secretory activity of the cells. RESULTS: Transfection of B7H7 siRNA into mDCs was performed in optimal conditions, and the siRNA transfection effectively reduced B7H7 mRNA expression in a dose-dependent manner. SiRNA-mediated B7H7 knockdown in mDCs enhanced maturation and activation of the DCs, as demonstrated by an increased surface expression of CD11c, CD86, and CD40. Co-culture experiments revealed that B7H7-silenced mDCs had more capacity to induce T cell proliferation compared to non-transfected mDCs. The cytokine production patterns of T cells were also altered. Upon examining the levels of TGF-ß, IL-4, and IFN-γ released by CD3+ T cells in the co-culture supernatant, we found that silencing B7H7 in mDCs resulted in a rise in IL-4 secretion and a reduction in TGF-ß levels compared to mDCs that were not transfected. CONCLUSIONS: The study found that suppressing B7H7 expression in DCs significantly enhances their maturation and stimulatory activity when exposed to gastric cancer cell lysate. These B7H7-silenced DCs can substantially increase cytokine production and promote co-cultured T-cell expansion. Consequently, inhibiting B7H7 in DCs may offer a practical strategy to enhance the ability of DCs to initiate T lymphocyte responses and improve the effectiveness of DC-based cell therapy for cancer patients.

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.

Sirtuins and Metabolism Biomarkers in Relapsing-Remitting and Secondary Progressive Multiple Sclerosis: a Correlation Study with Clinical Outcomes and Cognitive Impairments.

Multiple sclerosis (MS) is a primary inflammatory demyelinating disease with different clinical courses and subtypes. The present study aimed to determine whether mitochondrial dysfunction and sirtuins 1 and 3, as metabolism and epigenetic modifying factors, might contribute to MS disease progression measured by physical disability and cognitive impairment.The volunteers (n = 20 controls, n = 59 MS) were recruited and assessed for cognitive function and disability scores; then, patients were clinically classified as relapsing-remitting (RR) in remission phase, RR in relapse phase, and secondary progressive MS. We measured sirtuin (SIRT) 1 and 3 levels, mitochondrial complex I, IV, aconitase, and α-ketoglutarate dehydrogenase (α-KGD) activity in the peripheral blood mononuclear cells (PBMCs). Furthermore, SIRT1, pyruvate, lactate, and cytochrome c (Cyt c) were determined in plasma. Finally, we performed postmortem tissue immunohistochemistry to assess the level of SIRT1 and SIRT3 in the brain lesions of patients with MS.Increased disability and cognitive impairment in patients were correlated. Plasma level of lactate showed a correlation with the disability in MS patients; moreover, a trend toward increased Cyt c plasma level was observed. Investigation of PBMCs exhibited decreased SIRT1 during the relapse phase along with a reduced complex IV activity in all MS subgroups. α-KGD activity was significantly increased in the RR-remission, and SIRT3 was elevated in RR-relapse group. This elevation correlated with disability and cognitive impairment. Finally, immunohistochemistry demonstrated increased levels of SIRT1 and 3 in the brain active lesion of patients with MS.Our data suggest that mitochondrial dysfunction and alteration in some epigenetics and metabolism modifying factors in the CNS and peripheral blood cells may contribute or correlate with MS progression.

Neuroglial components of brain lesions may provide new therapeutic strategies for multiple sclerosis.

Multiple sclerosis (MS) is a chronic autoimmune and demyelinating disease of the central nervous system (CNS) which leads to focal demyelinated lesions in the brain and spinal cord. Failure of remyelination contributes to chronic disability in young adults. Characterization of events occurring during the demyelination and remyelination processes and those of which subsequently limit remyelination or contribute to demyelination can provide the possibility of new therapies development for MS. Most of the currently available therapies and investigations modulate immune responses and mediators. Since most therapeutic strategies have unsatisfied outcomes, developing new therapies that enhance brain lesion repair is a priority. A close look at cellular and chemical components of MS lesions will pave the way to a better understanding of lesions pathology and will provide possible opportunities for repair strategies and targeted pharmacotherapy. This review summarizes the lesion components and features, particularly the detrimental elements, and discusses the possibility of suggesting new potential targets as therapies for demyelinating diseases like MS.

Metformin restores cognitive dysfunction and histopathological deficits in an animal model of sporadic Alzheimer's disease.

Background: Metformin has been introduced as a neuroprotective agent in recent years. Here we evaluate the therapeutic effects of metformin in sporadic mouse model of Alzheimer's disease (SAD). Methods: AD was induced by streptozotocin (STZ, 0.5 mg/kg) on days 1 and 3. Metformin (MET, 200 mg/kg per day) was used for two weeks. Novel objective recognition (NOR) and Barnes Maze test were used to test the learning and memory. Nissl staining was used as s histological method for counting the dying neurons in different regions of hippocampus. Immunofluorescence staining against glial fibrillary acidic protein (GFAP), ionized calcium binding adaptor molecule 1 (Iba1) and NeuN were used to visualize reactive astrocytes, microglia and neurons, respectively. Results: In NOR test, the discrimination indices in the STZ group were significantly lower than the control and treatment groups. Goal sector/non-goal sector (GS/NGS) ratio index in Barnes maze was increased in metformin group compared to other groups. The number of dying neurons was increased by SAD and metformin reduced it. GFAP level was increased in CA1, CA3 and cortex of STZ group and reversed following the treatment. Iba1 level was significantly higher in STZ group in CA3 and cortex regions compared to Control and decreased by metformin in CA3 and cortex. Counting NeuN+ cells demonstrated significant reduction of neurons in DG+CA1 and CA3 after SAD induction. Significance: Metformin decreased inflammatory cells and reactive astrocytes as well as the dying neurons in the hippocampus region and the cortex in SAD, and improved the cognitive performance.

Allergen Induces Depression-like Behavior in Association with Altered Prefrontal-hippocampal Circuit in Male Rats.

Allergic asthma is a common chronic inflammatory condition associated with psychiatric comorbidities. Notably depression, correlated with adverse outcomes in asthmatic patients. Peripheral inflammation's role in depression has been shown previously. However, evidence regarding the effects of allergic asthma on the medial prefrontal cortex (mPFC)-ventral hippocampus (vHipp) interactions, an important neurocircuitry in affective regulation, is yet to be demonstrated. Herein, we investigated the effects of allergen exposure in sensitized rats on the immunoreactivity of glial cells, depression-like behavior, brain regions volume, as well as activity and connectivity of the mPFC-vHipp circuit. We found that allergen-induced depressive-like behavior was associated with more activated microglia and astrocytes in mPFC and vHipp, as well as reduced hippocampus volume. Intriguingly, depressive-like behavior was negatively correlated with mPFC and hippocampus volumes in the allergen-exposed group. Moreover, mPFC and vHipp activity were altered in asthmatic animals. Allergen disrupted the strength and direction of functional connectivity in the mPFC-vHipp circuit so that, unlike normal conditions, mPFC causes and modulates vHipp activity. Our results provide new insight into the underlying mechanism of allergic inflammation-induced psychiatric disorders, aiming to develop new interventions and therapeutic approaches for improving asthma complications.

Evaluation of a New Method of Leukocyte Extractions from the Leukoreduction Filter.

This study's purpose was to optimize the leukocyte extraction protocol and evaluate the efficacy of this new protocol. 12BioR blood filters were collected from Tehran Blood Transfusion Center. A twosyringe system and Multi-step rinsing were designed for cell extraction. The final purpose of this optimization was: (1) removed the residual RBCs, (2) reversed the leukocyte trapping process, and (3) remove the microparticles to obtain the high yield of target cells. Finally, Extracted cells were evaluated by Automated Cell count; Samples smear differential cell count, Trypan blue, and Annexin-PI staining. The results showed that on average 11.88 × 108 ± 3.32 leukocytes recovered after indirect washing and that the mean count of granulocytes, lymphocytes, and Monocyte in this sample was 5.24 ± 2.18 × 108, 5.57 ± 1.74 × 108, and 0.56 ± 0.38 × 108 respectively. Also, the mean percent of manual differential cell count after concentration was 42.81%, 41.80%, and 15.82% for granulocytes, lymphocytes, and monocytes respectively. Moreover, viability and apoptosis assay showed > 95% viability in mononuclear cells recovered from LRFs. It is concluded that the use of a double-syringe system and RBC and microparticles removal from leukoreduction filters lead to acceptable viable leukocyte count that can be used in in vitro and in vivo studies.

Electrical impulses evoked activity patterns in ventral tegmental area and locus coeruleus modulate endogenous and learning-dependent disparity of cell proliferation along the mouse dentate gyrus.

This study aimed to examine the effects of the ventral tegmental area (VTA) and the locus coeruleus (LC) patterned electrical stimulation on hippocampal-dependent learning and hippocampal neurogenesis in adult mouse. For this, mice were given unilateral electrical stimulation of VTA or LC using phasic or tonic stimulation protocols. Behavior acquisition rates were evaluated using the Barnes maze (BM) and a passive avoidance (PA) task. Cell proliferation was measured in the dorsal (dDG), intermediate (iDG) and ventral (vDG) dentate gyrus (DG) using Ki67 immunohistochemistry. We showed that the levels of cell proliferation were significantly different in three highlighted parts of the DG. The behavioral testing paradigms themselves were sufficient to alter cell proliferation indices along the dentate gyrus. The phasic LC modulation treatment enhanced behavioral acquisition of the BM and cell proliferation in the dDG, while tonic VTA stimulation improved PA acquisition and increased cell proliferation in the iDG. It is concluded that electrical impulses-evoked phasic or tonic activity patterns in the LC and VTA could modulate endogenous and learning dependent disparity of cell proliferation along the adult mouse DG.

The protective effect of inhaled corticosteroid on lung inflammation and breathing pattern complexity in a rat model of asthma.

Asthma is a heterogeneous disease in which the complexity of the breathing pattern reduces as the severity of the disease increases. Since the pathophysiological basis of reduced breathing pattern complexity in asthma is unclear, in this study, we investigated the effect of reducing inflammation using an inhaled corticosteroid (fluticasone propionate) on the breathing pattern of a rat model of asthma. Detrended fluctuation analysis, sample entropy, and cross-sample entropy analysis of both inter-breath interval and respiratory volume time series showed that early treatment with inhaled corticosteroids not only diminishes lung inflammation and airway hyper-responsiveness, but also has a protective effect against the reduction of breathing pattern complexity due to asthma. However, late treatment had a partial effect on asthma-induced respiratory pattern changes. Since inflammation is a key factor in shifting breathing dynamics away from normal fluctuations, these findings further emphasize the importance of early treatment of asthma with corticosteroids.

The Epigenetic Contribution to the Pathogenesis of Psoriasis: Recent Advances.

Psoriasis is defined as a chronic autoimmune disorder of the skin in which abnormal proliferation and differentiation of keratinocytes are blamed as the central culprit of disease etiopathogenesis. A complex interplay between environmental factors and genetic risk factors has been suggested to trigger the disease. However, epigenetic regulation appears to connect external stimuli and genetic abnormalities in the development of psoriasis. The discordance in the prevalence of psoriasis between monozygotic twins and environmental factors that contribute to its onset have caused a paradigm shift regarding the mechanisms underlying the pathogenesis of this disease. Epigenetic dysregulation may be involved in aberrancies of keratinocyte differentiation, T-cell activation, and other plausible cells, leading to the initiation and perpetuation of psoriasis. Epigenetics is characterized by heritable alterations in the transcription of genes without nucleotide change and is commonly considered at three levels, i.e., DNA methylation, histone modifications, and microRNAs. To date, scientific evidence has indicated abnormal DNA methylation, histone modifications, and non-coding RNA transcription in psoriatic patients. In order to reverse aberrant epigenetic changes in psoriasis patients, several compounds and drugs (epi-drugs) have been developed to affect the major enzymes involved in the methylation of DNA, or the acetylation of histones, which aim to correct the aberrant methylation and acetylation patterns. A number of clinical trials have suggested the therapeutic potential of such drugs in the treatment of psoriasis. In the present review, we attempt to clarify recent findings with respect to epigenetic irregularities in psoriasis and discuss future challenges.

The properties of long-term potentiation at SC-CA1/ TA-CA1 hippocampal synaptic pathways depends upon their input pathway activation patterns.

Long-term potentiation (LTP) has been considered as a cellular mechanism of memory. Since the Schaffer collateral (SC) and temporoammonic (TA) inputs to CA1 are distinct synaptic pathways that could mediate different cognitive functions, this study was therefore aimed to separately study and compare the properties of LTP of these two synaptic pathways. In the current study we used slice electrophysiological methods to compare various properties of these two synaptic pathways in response to single, paired pulse stimulation, and to three standard protocols for inducing LTP: the high frequency electrical stimulation (HFS), theta-burst (TBS), and primed burst (PBs) stimulation. We found that the SC-CA1 synapses could produce bigger maximum synaptic responses than TA-CA1 synapses. In addition, we showed that paired-pulse ratios of the SC-CA1 synapses were higher than TA-CA1 synapses at certain inter-pulses intervals. Finally, we showed a higher LTP% was induced by PBs or TBS at the SC-CA1 synapse than the TA-CA1 synapse. Briefly, our findings suggest the differential basal synaptic transmission, paired-pulse evoked synaptic responses, and LTP exhibition of the hippocampal SC-CA1/ TA-CA1 synaptic pathways, which may rely on spontaneous and evoked activity pattern at the local circuit level.

Glycolysis inhibition partially resets epilepsy-induced alterations in the dorsal hippocampus-basolateral amygdala circuit involved in anxiety-like behavior.

Pharmacoresistant temporal lobe epilepsy affects millions of people around the world with uncontrolled seizures and comorbidities, like anxiety, being the most problematic aspects calling for novel therapies. The intrahippocampal kainic acid model of temporal lobe epilepsy is an appropriate rodent model to evaluate the effects of novel interventions, including glycolysis inhibition, on epilepsy-induced alterations. Here, we investigated kainic acid-induced changes in the dorsal hippocampus (dHPC) and basolateral amygdala (BLA) circuit and the efficiency of a glycolysis inhibitor, 2-deoxy D-glucose (2-DG), in resetting such alterations using simultaneous local field potentials (LFP) recording and elevated zero-maze test. dHPC theta and gamma powers were lower in epileptic groups, both in the baseline and anxiogenic conditions. BLA theta power was higher in baseline condition while it was lower in anxiogenic condition in epileptic animals and 2-DG could reverse it. dHPC-BLA coherence was altered only in anxiogenic condition and 2-DG could reverse it only in gamma frequency. This coherence was significantly correlated with the time in which the animals exposed themselves to the anxiogenic condition. Further, theta-gamma phase-locking was lower in epileptic groups in the dHPC-BLA circuit and 2-DG could considerably increase it.

A distinct impact of repeated morphine exposure on synaptic plasticity at Schaffer collateral-CA1, temporoammonic-CA1, and perforant pathway-dentate gyrus synapses along the longitudinal axis of the hippocampus.

We aimed to study how morphine affects synaptic transmission in the dentate gyrus and CA1 regions along the hippocampal long axis. For this, recording and measuring of field excitatory postsynaptic potentials (fEPSPs) were utilized to test the effects of repeated morphine exposure on paired-pulse evoked responses and long-term potentiation (LTP) at Schaffer collateral-CA1 (Sch-CA1), temporoammonic-CA1 (TA-CA1) and perforant pathway-dentate gyrus (PP-DG) synapses in transverse slices from the dorsal (DH), intermediate (IH), and ventral (VH) hippocampus in adult male rats. After repeated morphine exposure, the expression of opioid receptors and the α1 and α5 GABAA subunits were also examined. We found that repeated morphine exposure blunt the difference between the DH and the VH in their basal levels of synaptic transmission at Sch-CA1 synapses that were seen in the control groups. Significant paired-pulse facilitation of excitatory synaptic transmission was observed at Sch-CA1 synapses in slices taken from all three hippocampal segments as well as at PP-DG synapses in slices taken from the VH segment in the morphine-treated groups as compared to the control groups. Interestingly, significant paired-pulse inhibition of excitatory synaptic transmission was observed at TA-CA1 synapses in the DH slices from the morphine-treated group as compared to the control group. While primed-burst stimulation (a protocol reflecting normal neuronal firing) induced a robust LTP in hippocampal subfields in all control groups, resulting in a decaying LTP at TA-CA1 synapses in the VH slices and at PP-DG synapses in both the IH and VH slices taken from the morphine-treated rats. In the DH of morphine-treated rats, we found increased levels of the mRNAs encoding the α1 and α5 GABAA subunits as compared to the control group. Taken together, these findings suggest the potential mechanisms through which repeated morphine exposure causes differential changes in circuit excitability and synaptic plasticity in the dentate gyrus and CA1 regions along the hippocampal long axis.

Cis-p-tau plays crucial role in lysolecithin-induced demyelination and subsequent axonopathy in mouse optic chiasm.

Multiple sclerosis (MS) is an autoimmune demyelinating disease that leads to axon degeneration as the major cause of everlasting neurological disability. The cis-phosphorylated tau (cis-p-tau) is an isoform of tau phosphorylated on threonine 231 and causes tau fails to bind micro-tubules and promotes assembly. It gains toxic function and forms tangles in the cell which finally leads to cell death. An antibody raised against cis- p-tau (cis mAb) detects this isoform and induces its clearance. Here, we investigated the formation of cis-p-tau in a lysophosphatidylcholine (LPC)-induced prolonged demyelination model as well as the beneficial effects of its clearance using cis mAb. Cis -p-tau was increased in the lesion site, especially in axons and microglia. Behavioral and functional studies were performed using visual cliff test, visual placing test, and visual evoked potential recording. Cis-p-tau clearance resulted in decreased gliosis, protected myelin and reduced axon degeneration. Analysis of behavioral and electrophysiological data showed that clearance of cis-p-tau by cis mAb treatment improved the visual acuity along with the integrity of the optic pathway. Our results highlight the opportunity of using cis mAb as a new therapy for protecting myelin and axons in patients suffering from MS.

In-line leukoreduction filters: A new source of microparticle for human and animal study.

INTRODUCTION: The isolation of microparticles (MPs) from leukoreduction filters (LRFs) during cell extraction process introduced LRFs as a precious source of MPs for animal and human study. METHOD: LRFs were collected from Tehran Blood Transfusion Center. The back-flushing method was used for leukocyte extraction from the LRFs. MPs were isolated through double-step centrifugation. Dynamic light scattering (DLS), electron microscopy (EM), and flow cytometry were performed for the evaluation of MPs size, morphology, and structural properties respectively. Statistical analyses were carried out to evaluation of differences between test and control groups. a p-value less than 0.05 indicates significant differences. RESULT: DLS analysis showed that the average MP size in the test and control groups was 654.83 nm and 233.68 nm respectively. SEM images showed the spherical, oval, cell fragment, and micro-aggregate particles and TEM images demonstrated the mitochondrial-like body in the MPs. Flow cytometry studies also showed a significant increase in the percent of CD41, and CD14, and a significant decrease in the percent of CD235a in the test group compared to control (P value=0.029, P value=0.035, P value= 0.001 respectively). Moreover, the percentage of CD34 MPs indicated a borderline difference between the two groups (P value= 0.075). Finally count of MPs in the test and control groups was 1202095.34 and 280948.64, respectively and the difference was significant (P value=0.008). CONCLUSION: It is concluded that LRFs are a potential source of the large volume of various cell MPs with different phenotypical and structural properties for animal and human phase studies. Moreover, the investigation of LRFs as a source of different types of exosomes can shed new light on extracellular vesicle studies.

Peptide mediated targeted delivery of gold nanoparticles into the demyelination site ameliorates myelin impairment and gliosis.

Drug development for multiple sclerosis (MS) clinical management focuses on both neuroprotection and repair strategies, and is challenging due to low permeability of the blood-brain barrier, off-target distribution, and the need for high doses of drugs. The changes in the extracellular matrix have been documented in MS patients. It has been shown that the expression of nidogen-1 increases in MS lesions. Laminin forms a stable complex with nidogen-1 through a heptapeptide which was selected to target the lesion area in this study. Here we showed that the peptide binding was specific to the injured area following lysophosphatidylcholine (LPC) induced demyelination. In vivo data showed enhanced delivery of the peptide-functionalized gold nanoparticles (Pep-GNPs) to the lesion area. In addition, Pep-GNPs administration significantly enhanced myelin content and reduced astrocyte/microglia activation. Results demonstrated the possibility of using this peptide to target and treat lesions in patients suffering from MS.