Local delivery of fingolimod through PLGA nanoparticles and PuraMatrix-embedded neural precursor cells promote motor function recovery and tissue repair in spinal cord injury.

Spinal cord injury (SCI) is a devastating clinical problem that can lead to permanent motor dysfunction. Fingolimod (FTY720) is a sphingosine structural analogue, and recently, its therapeutic benefits in SCI have been reported. The present study aimed to evaluate the therapeutic efficacy of fingolimod-incorporated poly lactic-co-glycolic acid (PLGA) nanoparticles (nanofingolimod) delivered locally together with neural stem/progenitor cells (NS/PCs) transplantation in a mouse model of contusive acute SCI. Fingolimod was encapsulated in PLGA nanoparticles by the emulsion-evaporation method. Mouse NS/PCs were harvested and cultured from embryonic Day 14 (E14) ganglionic eminences. Induction of SCI was followed by the intrathecal delivery of nanofingolimod with and without intralesional transplantation of PuraMatrix-encapsulated NS/PCs. Functional recovery, injury size and the fate of the transplanted cells were evaluated after 28 days. The nanofingolimod particles represented spherical morphology. The entrapment efficiency determined by UV-visible spectroscopy was approximately 90%, and the drug content of fingolimod loaded nanoparticles was 13%. About 68% of encapsulated fingolimod was slowly released within 10 days. Local delivery of nanofingolimod in combination with NS/PCs transplantation led to a stronger improvement in neurological functions and minimized tissue damage. Furthermore, co-administration of nanofingolimod and NS/PCs not only increased the survival of transplanted cells but also promoted their fate towards more oligodendrocytic phenotype. Our data suggest that local release of nanofingolimod in combination with three-dimensional (3D) transplantation of NS/PCs in the acute phase of SCI could be a promising approach to restore the damaged tissues and improve neurological functions.

Extracellular Vesicles Derived from Human Umbilical Cord Perivascular Cells Improve Functional Recovery in Brain Ischemic Rat via the Inhibition of Apoptosis.

Background: Ischemic stroke, as a health problem caused by the reduced blood supply to the brain, can lead to the neuronal death. The number of reliable therapies for stroke is limited. Mesenchymal stem cells (MSCs) exhibit therapeutic achievement. A major limitation of MSC application in cell therapy is the short survival span. MSCs affect target tissues through the secretion of many paracrine agents including extracellular vesicles (EVs). This study aimed to investigate the effect of human umbilical cord perivascular cells (HUCPVCs)-derived EVs on apoptosis, functional recovery, and neuroprotection. Methods: Ischemia was induced by middle cerebral artery occlusion (MCAO) in male Wistar rats. Animals were classified into sham, MCAO, MCAO + HUCPVC, and MCAO + EV groups. Treatments began at two hours after ischemia. Expressions of apoptotic-related proteins (BAX/BCl-2 [B-cell lymphoma-2] and caspase-3 and -9), the amount of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells, neuronal density (microtubule-associated protein 2 [MAP2]), and dead neurons (Nissl staining) were assessed on day seven post MCAO. Results: Administration of EVs improved the sensorimotor function (p < 0.001) and reduced the apoptotic rate of Bax/Bcl-2 ratio (p < 0.001), as well as caspases and TUNEL-positive cells (p < 0.001) in comparison to the MCAO group. EV treatment also reduced the number of dead neurons and increased the number of MAP2+ cells in the ischemic boundary zone (p < 0.001), as compared to the MCAO group. Conclusion: Our findings showed that HUCPVCs-derived EVs are more effective than their mother's cells in improving neural function, possibly via the regulation of apoptosis in the ischemic rats. The strategy of cell-free extracts is, thus, helpful in removing the predicaments surrounding cell therapy in targeting brain diseases.

Subventricular zone-derived extracellular vesicles promote functional recovery in rat model of spinal cord injury by inhibition of NLRP3 inflammasome complex formation.

Spinal cord injury (SCI) is the destruction of spinal cord motor and sensory resulted from an attack on the spinal cord, which can cause significant physiological damage. The inflammasome is a multiprotein oligomer resulting in inflammation; the NLRP3 inflammasome composed of NLRP3, apoptosis-associated speck-like protein (ASC), procaspase-1, and cleavage of procaspase-1 into caspase-1 initiates the inflammatory response. Subventricular Zone (SVZ) is the origin of neural stem/progenitor cells (NS/PCs) in the adult brain. Extracellular vesicles (EVs) are tiny lipid membrane bilayer vesicles secreted by different types of cells playing an important role in cell-cell communications. The aim of this study was to investigate the effect of intrathecal transplantation of EVs on the NLRP3 inflammasome formation in SCI rats. Male wistar rats were divided into three groups as following: laminectotomy group, SCI group, and EVs group. EVs was isolated from SVZ, and characterized by western blot and DLS, and then injected into the SCI rats. Real-time PCR and western blot were carried out for gene expression and protein level of NLRP3, ASC, and Caspase-1. H&E and cresyl violet staining were performed for histological analyses, as well as BBB test for motor function. The results indicated high level in mRNA and protein level in SCI group in comparison with laminectomy (p < 0.001), and injection of EVs showed a significant reduction in the mRNA and protein levels in EVs group compared to SCI (p < 0.001). H&E and cresyl violet staining showed recovery in neural cells of spinal cord tissue in EVs group in comparison with SCI group. BBB test showed the promotion of motor function in EVs group compared to SCI in 14 days (p < 0.05). We concluded that the injection of EVs could recover the motor function in rats with SCI and rescue the neural cells of spinal cord tissue by suppressing the formation of the NLRP3 inflammasome complex.

Effects of neural stem cell-derived extracellular vesicles on neuronal protection and functional recovery in the rat model of middle cerebral artery occlusion.

Stroke imposes a long-term neurological disability with limited effective treatments available for neuronal recovery. Transplantation of neural stem cells (NSCs) is reported to improve functional outcomes in the animal models of brain ischemia. However, the use of cell therapy is accompanied by adverse effects, so research is growing to use cell-free extracts such as extracellular vesicles (EVs) for targeting brain diseases. In the current study, male Wistar albino rats (20 months old) were subjected to middle cerebral artery occlusion (MCAO). Then, EVs (30 µg) were injected at 2 hours after stroke onset via an intracerebroventricular (ICV) route. Measurements were done at day 7 post-MCAO. EVs administration reduced lesion volume and steadily improved spontaneous locomotor activity. EVs administration also reduced microgliosis (ionized calcium-binding adaptor molecule 1 (Iba1)+ cells) and apoptotic (terminal-deoxynucleotidyl transferase mediated nick end labelling [TUNEL]) positive cells and increased neuronal survival (neuronal nuclear (NeuN)+ cells) in the ischemic boundary zone (IBZ). However, it had no effect on neurogenesis within the sub-ventricular zone (SVZ) but decreased cellular migration toward the IBZ (doublecortin (DCX)+ cells). The results of this study showed neuroprotective and restorative mechanisms of NSC-EVs administration, which may offer new avenues for therapeutic intervention of brain ischemia. SIGNIFICANCE OF THE STUDY: Based on our results, EVs administration can effectively reduce microglial density and neuronal apoptosis, thereby steadily improves functional recovery after MCAO. These findings provide the beneficial effect of NSC-EVs as a new biological treatment for stroke.

Polymorphisms in the Estrogen Receptor Beta Gene and the Risk of Unexplained Recurrent Spontaneous Abortion.

BACKGROUND: Recurrent Spontaneous Abortion (RSA) is caused by multiple genetic and non-genetic factors. Around 50% of the RSA cases have no known etiology and are considered as Unexplained RSA (URSA). Estrogens, via binding to their receptors, play an important role in female reproduction. This study aimed to investigate whether single nucleotide polymorphisms (SNPs; +1082G/A, +1730G/A and rs1256030 C/T) in the estrogen receptor beta (ESR2) gene are associated with susceptibility to URSA in a population of Iranian women. METHODS: In this case-control study, the study groups consisted of 240 subjects with a history of URSA and 102 fertile women as controls. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) were measured on day 2-3 of menstrual cycle. Two functional SNPs, +1082G/A (a silent mutation in exon 5) and +1730G/A (3' untranslated region of the exon 8), and one intron, rs1256030C/T, in the ESR2 gene were genotyped, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: Serum levels of LH were significantly increased in URSA women. No significant differences in distribution of +1082G/A, +1730G/A and rs1256030C/T between URSA and control groups were observed. CONCLUSION: Our findings suggest that the studied SNPs on ESR2 gene may not be associated with URSA.

Investigation on estrogen receptor alpha gene polymorphisms in Iranian women with recurrent pregnancy loss.

BACKGROUND: Recurrent pregnancy loss (RPL) is a multifactorial disorder. Environmental factors and genetics can affect pregnancy outcomes. OBJECTIVE: Conflicting data suggest an association between estrogen receptor alpha (ESR1) gene polymorphisms and RPL. In this study, such association was investigated in Iranian women with RPL. MATERIALS AND METHODS: In this case control study, blood samples were collected from 244 women with a history of three or more consecutive pregnancy losses and 104 healthy women with at least two live births. Using polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP), we studied -397C/T and -351A/G polymorphisms on ESR1 gene in case and control subjects. RESULTS: The genotypic frequencies of -397C/T and -351A/G polymorphisms on ESR1were not significantly different between RPL and control groups (p=0.20 and p=0.09, respectively). A significantly negative correlation was observed between -397C/T and -351A/G (r=-0.852, p<0.001) in RPL women and complete linkage disequilibrium between the investigated polymorphisms was found (D': 0.959; r-square= 0.758, p<0.001). CONCLUSION: This investigation suggests that the analyzed polymorphisms on ESR1gene are not associated with an increased risk of RPL in the studied population.