Cell Journal (Yakhteh)

55-61

Authors: Elham Hoveizi, Shima Tavakol

Objective: The β-catenin signaling pathway promises the potential for differentiation of stem cells into definitive endoderm (DE) cells as precursors of beta cells. Therefore, it can be considered as an inducer for cell replacement therapies in diabetes. The main goal of this research is to successfully culture and induce differentiation of human Wharton’s jelly mesenchymal stem cells (hWJMSCs) into Sox17-expressing cells using a Wnt/β-catenin pathway agonist (SKL2001) plus nanoparticles on a polylactic acid/chitosan (PLA/Cs) nanocomposite scaffold. Materials and Methods: In this experimental study, the nanocomposite was prepared through an electrospinning method and hWJMSCs were isolated through an explant technique. The morphology and the cell viability were evaluated by scanning electron microscopy (SEM) and 3-(4, 5- Dimethylthiazol-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Here, we present two differentiation protocols: the first one is induction with SKL2001; and the second one is with a combination of SKL2001 and zinc oxide nanoparticles (nZnO). Real-time quantitative reverse transcription (QRT-PCR) and immunocytochemistry analysis are carried out to examine the expression of specific markers in the differentiated cells. Results: The nanocomposite had appropriate biocompatibility for cell adhesion and growth. While the hWJMSCs cultured on the PLA/Cs scaffolds differentiated into DE cells in the presence of SKL2001, introducing nZnO to their environment increased the differentiation process. Analyses of DE-specific markers including SOX17, FOXA2, and gooscoid (GSC) genes in mRNA level, indicated significantly high levels of expression in the SKL2001/nZnO group, followed by SKL2001 group compared to the control. Conclusion: Our results show the beneficial effects of the Wnt/β-catenin pathway agonist in three-dimensional (3D) cultures in cell replacement therapy for diabetes.

69-75

Authors: Vahid Baghdadi, Reza Ranjbaran, Fatemeh Yari, Mohammad Hessam Rafiee

Objective: Although cold storage of platelets (PLTs) could decrease the risk of bacterial growth, it could affect on the PLTs viability and hemostatic function. At cold temperatures, trehalose can be used to substitute water, inhibit the solid-liquid transition phase of the PLT membrane, and stop Glycoprotein Ibα (GPIbα) polymerization. In this study, we evaluated the potential of trehalose for reducing the negative effects of cold storage on the apoptosis and the clearancerates of PLTs after long-term storage at cold. Materials and Methods: In this experimental study, PLT concentrates (PCs) were maintained for five days in the different circumstances. PLTs were subsequently counted by using an automated hematology analyzer. Also water-soluble tetrazolium salt (WST-1) assay was performed to estimate the viability of PLTs. The activity of lactate dehydrogenase enzyme (LDH) was determined by a biochemical analyzer. And human active caspase-3 levels were measured by using enzyme-linked immunosorbent assay (ELISA) method. Also, we applied flow cytometry technique. Results: PLTs count and viability were higher, while LDH amount was lower in trehalose-treated PLTs when compared with two other groups (P=0.03). The highest increase in the amount of caspase-3 levels in the PLTs was observed at 4°C. However, trehalose-treated and 4°C PLTs had a lower amount of active caspase-3 in comparison with 4°C PLTs. The level of PS expression on PLTs was lower in the trehalose-treated PLTs in compared with the two other groups(P=0.03). PLTs ingestion by HepG2 cells was enhanced in the 4°C-stored PLTs. However, the ingestion rate was significantly reduced in the trehalose-treated PLTs on day 5 of storage (P=0.03). Conclusion: Trehalose can moderate the effects of cold temperature on the apoptosis, viability, and the survival rate of PLTs. It also decreases the ingestion rate of refrigerated PLTs in vitro.

85-90

Authors: Fatemeh Salimian, Mohammad Nabiuni, Ensieh Salehghamari

Objective: Melittin is one of the natural components of bee venom (Apis mellifera), and its anticancer and antimetastatic properties have been well established, but the underlying mechanism remains elusive. The MDA-MB-231 is a triplenegative cell line that is highly aggressive and invasive. Besides, many critical proteins are involved in tumor invasion and metastasis. In this study, we investigated whether melittin inhibits the migration and metastasis of epidermal growth factor (EGF)-induced MDA-MB-231 cells via the suppression of SDF-1α/CXCR4 and Rac1-mediated signaling pathways. Materials and Methods: In this experimental study, cells were treated with melittin (0.5-4 μg/ml), and the toxicity of melittin was assessed by the MTT assay. Afterward, the migration assay was conducted to measure the degree of the migration of EGF-induced cells. The western blot technique was performed to analyze the rate of Rac1, p-Rac1, SDF- 1α, and CXCR4 expression in different groups. Results: The results demonstrated that melittin markedly suppressed the migration of EGF-induced cells and decreased the expression of p-Rac1, CXCR4, and SDF-1α proteins. Conclusion: The results of the present study suggested that the anti-tumor properties of melittin could be through the blocking of the SDF-1α/CXCR4 signaling pathway, which is beneficial for the reduction of tumor migration and invasion.

99-102

Authors: Fereshteh Kohandani, Parham Jazireian, Raha Favaedi, Mohammad Ali Sadighi Gilani, Seyed Mohammad Moshtaghioun, Maryam Shahhoseini

Objective: Bromodomain testis associated (BRDT), a testis-specific member of the Bromo- and Extra-Terrminal domain (BET) protein family, is involved in spermatogenesis and, more specifically, chromatin remodeling. In the post-meiotic spermatogenic cells, BRDT protein binds to the hyperacetylated histones and facilitates their replacement with transition proteins (TPs), particularly protamines, which are essential for chromatin condensation. The current research was conducted to assess the expression and epigenetic profile of BRDT in the testis tissues of infertile men. Materials and Methods: In this case-control study, three groups were included: positive control group: obstructive azoospermia (OA, n=10), round spermatid maturation arrest group (SMA, n=10) and negative control group: sertoli cellonly syndrome (SCOS, n=10). Using quantitative real-time polymerase chain reaction (PCR), the expression profile of BRDT was generated. Also, ChIP-real time PCR was used to measure the following histone marks: H3K9ac, H3K9me3, H3K4me3, H3K27me3 on the promoter region of BRDT. Results: Our data indicated that BRDT expression decreased in the SMA group in comparison with the positive control group and this finding is in line with the ChIP results obtained in this group. Conclusion: Based on these data, we postulate that BRDT gene has a vital role in the spermatogenesis and its decreased expression due to an aberrant epigenetic signaling might be associated with male infertility.