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Summary: Mouse testicular tissue is composed of seminiferous tubules and interstitial tissue. Mammalian spermatogenesis is divided into three stages: spermatocytogenesis (mitotic divisions) in which spermatogonial stem cells (SSCs) turn into spermatocytes, followed by two consecutive meiotic divisions in which spermatocytes form spermatids. Spermatids differentiate into spermatozoa during spermiogenesis. Various factors affect the process of spermatogenesis and the organization of cells in the testis. Any disorder in different stages of spermatogenesis will have negative effects on male fertility. The aim of the current study was to compare the in vitro and in vivo spermatogenesis processes before and after transplantation to azoospermic mice using ultrastructural techniques. In this study, mice were irradiated with single doses of 14 Gy 60Co radiation. SSCs isolated from neonatal mice were cultured in vitro for 1 week and were injected into the seminiferous tubule recipient's mice. Testicular cells of neonatal mice were cultured in the four groups on extracellular matrix-based 3D printing scaffolds. The transplanted testes (8 weeks after transplantation) and cultured testicular cells in vitro (after 3 weeks) were then processed for transmission electron microscopy studies. Our study's findings revealed that the morphology and ultrastructure of testicular cells after transplantation and in vitro culture are similar to those of in vivo spermatogenesis, indicating that spermatogenic cell nature is unaltered in vitro. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS) that leads to disability in middle‐aged individuals. High rates of apoptosis and inappropriate homing are limitations for the application of stem cells in cell therapy. Preconditioning of bone marrow mesenchymal stem cells (BMSCs) with stromal cell‐derived factor 1α (SDF‐1α), also called C‐X‐C motif chemokine 12 (CXCL12), is an approach for improving the functional features of the cells. The aim of this study was to investigate the therapeutic efficacy of intranasal delivery of SDF‐1α preconditioned BMSCs in the cuprizone‐induced chronically demyelinated mice model. BMSCs were isolated, cultured, and preconditioned with SDF‐1α. Then, intranasal delivery of the preconditioned cells was performed in the C57BL/6 mice receiving cuprizone for 12 weeks. Animals were killed at 30 days after cell delivery. SDF‐1α preconditioning increased C‐X‐C chemokine receptor type 4 (CXCR4) expression on the surface of BMSCs, improved survival of the cells, and decreased their apoptosis in vitro. SDF‐1α preconditioning also improved CXCL12 level within the brain, and enhanced spatial learning and memory (assessed by Morris water maze [MWM]), and myelination (assessed by Luxol fast blue [LFB] and transmission electron microscopy [TEM]). In addition, preconditioning of BMSCs with SDF‐1α reduced the protein expressions of glial fibrillary acidic protein and ionized calcium‐binding adapter molecule (Iba‐1) and increased the expressions of oligodendrocyte lineage transcription factor‐2 (Olig‐2) and adenomatous polyposis coli (APC), evaluated by immunofluorescence. The results showed the efficacy of intranasal delivery of SDF‐1α‐preconditioned BMSCs for improving remyelination in the cuprizone model of MS. [ABSTRACT FROM AUTHOR]

Introduction: Alzheimer's disease (AD) is one of the most common neurodegenerative disorders, which has much benefited from animal models to find the basics of its pathophysiology. In our previous work (Haghani, Shabani, Javan, Motamedi, & Janahmadi, 2012), a non-transgenic rat model of AD was used in electrophysiological studies. However, we did not investigate the histological aspects in the mentioned study. Methods: An AD model was developed through bilateral injection of amyloid-β peptides (Aβ) into the frontal cortices. Behavioral and histological methods were used to assess alterations in the memory and (ultra)structures. Furthermore, melatonin has been administered to assess its efficacy on this AD model. Results: Passive avoidance showed a progressive decline in the memory following Aβ injection. Furthermore, Nissl staining showed that Aβ neurotoxicity caused shrinkage of the CA1 pyramidal neurons. Neurodegeneration was clearly evident from Fluoro-jade labeled neurons in Aβ treated rats. Moreover, higher NF-κB immunoreactive CA1 pyramidal neurons were remarkably observed in Aβ treated rats. Ultrastructural analysis using electron microscopy also showed the evidence of subcellular abnormalities. Melatonin treatment in this model of AD prevented Aβ-induced increased NF-κB from immunoreaction and neurodegeneration. Discussion: This study suggests that injection of Aβ into the frontal cortices results in the memory decline and histochemical disturbances in CA1 pyramidal neurons. Furthermore, melatonin can prevent several histological changes induced by Aβ. [ABSTRACT FROM AUTHOR]

Objective: In cancer treatments, smart gene delivery via nanoparticles (NPs) can be targeted for cancer cells, while concurrently minimizing damage to healthy cells. This study assessed the efficiency of poly lactic-co-glycolic acid (PLGA)-miR 143/206 transfection on apoptosis in mouse leukemia cancer cells (El4) and spermatogonial stem cells (SSCs). Materials and Methods: In this experimental study, neonatal mouse spermatogonia cells and EL4 cancer cell lines were used. MicroRNA-PLGA NPs were prepared, characterized, and targeted with folate. Several doses were evaluated to obtain a suitable miR dose that can induce appropriate apoptosis in EL4 cells, while not harming SSCs. Cells were treated separately at 3 doses of each miR (for miR 143, doses of 25, 50 and 75 nmol and for miR 206, doses of 50, 100 and 150 nmol). The experiments were performed at 24, 48 and 72 hours. Viability and apoptosis were investigated by MTT and Annexin Kits. Results: Based on MTT assay results, the optimal dose of miR 143 was 75 nmol (59.87 ± 2.85 % SSC and 35.3 ± 0.78 % EL4) (P≤0.05), and for miR 206, the optimal dose was 150 nmol (54.82 ± 6.7 % SSC and 33.92 ± 3.01% EL4) (P≤0.05). The optimal time was 48 hours. At these doses, the survival rate of the EL4 cells was below the half maximal inhibitory concentration (IC50) and SSC survival was above 50%. Annexin V staining also confirmed the selected doses (for miR 143 total apoptosis was 6.62% ± 1.8 SSC and 37.4% ± 4.2 EL4 (P≤0.05), and miR 206 was (10.98% ± 1.5 SSC and 36.4% ± 3.7 EL4, P≤0.05). Conclusion: Using intelligent transfection by NPs, we were able to induce apoptosis on EL4 cells and maintain acceptable SSC survival rates. [ABSTRACT FROM AUTHOR]

Objective: Transplantation of bone marrow stromal cells (BMSCs) or Schwann cells (SC5) can facilitate axonal regeneration in peripheral nerve injuries. The aim of this study was to compare the effects of transplantation of BMSCs and SCs on functional recovery after injury to the sciatic nerve in the rat. Materials and Methods:ln this experimental research, adult male Wistar rats (n=24, 250-300 g) were used, BMSCs and SCs were cultured, and SCs were confirmed with anti S100 antibody. Rats were randomly divided into 3 groups (n=8 in each group): 1; control group: silicon tube filled with fibrin gel without the cells, 2; BMSCs group: silicon tube filled with fibrin gel seeded with BMSCs and 3; SCs group: silicon tube filled with fibrin gel seeded with SCs. The left sciatic nerve was exposed, a 10 mm segment removed, and a silicone tube interposed into this nerve gap. BMSCs and SCs were separately transplanted into the gap in the two experimental groups and were labeled with anti BrdU and Dil respectively. After 12 weeks electrophysiological and functional assessments were performed and analyzed by one-way analysis of variance (ANOVA). Results: Electrophysiological and functional assessments showed a significant difference between the experimental groups compared with the control group. Electrophysiological measures were significantly better in the SCs transplantation group compared with the BMSCs treatment group (p<0.05). Functional assessments showed no statistically significant difference between the BMSCs and SCs groups (p<0.05). Conclusion: Although both BMSCs and SCs have the potential to produce functional recovery after injury to the sciatic nerve in rats, electrophysiological evaluation confirms that the improvement after SCs transplantation is greater than that after BMSCs transplantation. [ABSTRACT FROM AUTHOR]

Objective: Previous studies have shown that transplantation of bone marrow stromal cells (BMSCs) into the contused spinal cord improves functional recovery and that administration of Schwann cells (SCs) after spinal cord injury (SCI) facilitates axonal regeneration. Although the efficacy of these treatments have been proven, when used individually, their resulting number of regenerated axons is small and locomotor recovery is modest; therefore, we decided to research whether co-transplantation of these cells can improve the outcome. Materials and Methods: Adult male Wistar rats (n=56), each weighting 250-300 grams were used. BMSCs and SCs were cultured and prelabeled with BrdU and 1,1' dioctadecyl 3,3,3',3' tetramethylindocarbocyanin perchlorate respectively. Contusion model of SCI was performed at the T8-9 level using NYU device (New York University device). The rats were divided into seven groups, each consisting of 8 animals. These groups included: a control group, three experimental groups and three sham groups. In the control group, only a laminectomy was performed. The three experiment groups were the BMSC, SC and co-transplant groups, and 7 days after injury, they received intraspinal BMSCs, SCs and the combination of BMSCs & SCs respectively. The sham groups received serum in the same manner. Locomotion in the groups was assessed using the basso, beatie and bresnahan (BBB) test at 1, 7, 14, 21, 28, 35, 42, 49 and 56 days after SCI. Results: More significant improvement was observed in the BBB scores of the co-transplant group (p<0.05) in comparison with BMSC and SC groups. Conclusion: This study shows that co-transplantation of BMSCs and SCs may provide a powerful therapy for SCI and become required for the development of combinatory treatment strategies in the future. [ABSTRACT FROM AUTHOR]