Large-scale analysis of MicroRNA expression in motor neuron-like cells derived from human umbilical cord blood mesenchymal stem cells.

Motor neuron diseases such as spinal cord injuries and amyotrophic lateral sclerosis are known as the most common disorders worldwide. Using stem cells (e.g., human umbilical cord blood mesenchymal stem cells) is currently a potent medical approach for modulating the impact of neural damages and regeneration of spinal cord injuries. MicroRNAs (miRNA) are taken into account as principal regulators during differentiation. The miRNAs play a significant role in stem cell self-renewal and fate determination. There are few studies on how miRNAs regulate neural differentiation in stem cells. The purpose of this study is to explore miRNA profiles of CB-MSCs during differentiation into motor neuron-like cells. Human CB-MSCs were isolated and characterized using flow cytometry. Cell differentiation has been induced by combining retinoic acid (RA) and sonic hedgehog (Shh) in a two-step protocol for 14 days. Then, cell differentiation was confirmed by immunocytochemistry and flow cytometry. The miRNA was analyzed using Illumina/Solexa sequencing platform. In this regard, three libraries were prepared to investigate the effect of these two biological morphogens on the miRNA profile of the differentiating cells. These libraries were Control (non-treated CB-MSCs), Test 1 (RA + /Shh +), and Test 2 (RA-/Shh-). Quantitative RT-PCR was employed to verify miRNA expression. CB-MSCs were spindle-shaped in morphology, and they did not express hematopoietic markers. After differentiation, the cells expressed motor neuron markers (i.e., Islet-1, SMI-32, and ChAT) at the protein level after 14 days. The analysis of miRNA sequencing demonstrated a significant up-regulation of miR-9-5p and miR-324-5p in Test 1 (RA + /Shh +). Also, there is a considerable down-regulation of mir-137 and let-7b in Test 2 (RA-/Shh-). These results have been obtained by comparing them with the Control library. Indeed, they were responsible for neuron and motor neuron differentiation and suppression of proliferation in neural progenitor cells. Furthermore, significant up-regulation was detected in some novel microRNAs involved in cholinergic, JAK-STAT, and Hedgehog and MAPK signaling pathways. CB-MSCs are potent to express motor neuron markers. This procedure has been performed by developing a two-week protocol and employing Shh and RA. The miRNA profile analysis showed a significant up-regulation in the expression of some miRs involved in neuron differentiation and motor neuron maturation. MiR-9-5p and miR-324-5p were up-regulated at the early stage of differentiation. Also, miR-137 and miR-let-7b were downregulated in the absence of RA and Shh. Furthermore, several novel miRNAs involved in cholinergic, Hedgehog, MAPK, and JAK-STAT signaling pathways have been detected. However, further studies are still necessary to validate their functions during motor neuron generation and maturation.

In Vitro Assessment of the Gene Expression of EZH-2 and P300 During Motor Neuron Differentiation of Human Umbilical Cord Blood Mesenchymal Stem Cells.

Introduction: Maintenance of neurogenesis depends on the function of some histone-modifying enzymes; including Enhancer of zeste homolog 2 (EZH2) and histone acetyltransferases (P300). The mechanism of epigenetic regulation and gene expression underlying the transition of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) into MNs has not been fully clarified. Methods: Two morphogens; sonic hedgehog (Shh: 100 ng/mL) and retinoic acid (RA: 0.01 mM) were involved in the specification of hUCB-MSCs into MNs after MSC characterization using Flow cytometry. Real time-quantitative PCR and immunocytochemistry were performed to find the expression of the genes at the level of mRNA and protein. Results: The expression of MN-related markers was confirmed at the level of mRNA and protein by induction of differentiation. The results were confirmed by immunocytochemistry and showed those mean cell percentages of 55.33%±15.885% and 49.67%±13.796% could express Islet-1 and ChAT, respectively. The gene expression level of Islet-1 and ChAT was significantly increased in the first and second week of exposure, respectively. After two weeks, the expression level of P300 and EZH-2 genes increased remarkably. No significant expression of Mnx-1 was detected when compared to the control sample. Conclusion: MN-related markers, Islet-1 and ChAT, were detected in differentiated cells of hUCB-MSCs, supporting the potency of cord blood cells in the regeneration of MN-related disorders. Assessing these epigenetic regulatory genes at the protein level can be suggested to confirm their functional epigenetic modifying effects during motor neuron differentiation.

Differentiation of Mesenchymal Stem Cells Derived From Human Adipose Tissue Into Cholinergic-like Cells: An in Vitro Study.

INTRODUCTION: Cholinergic-associated diseases currently constitute a significant cause of neurological and neurodegenerative disabilities. As the drugs are not efficient in improving the suffered tissues, stem cell treatment is considered an effective strategy for substituting the lost cells. METHODS: In the current study, we set out to investigate the differentiation properties of human Adipose-Derived Mesenchymal Stem Cells (AD-MSCs) into cholinergic-like cells by two morphogens of Retinoic Acid (RA) and Sonic Hedgehog (Shh) using a three-step in vitro procedure. The results were evaluated using real-time PCR, flow cytometry, and immunocytochemistry for two weeks. RESULTS: Our data showed that the cells could express cholinergic specific markers, including Islet-1, Acetylcholinesterase (AChE), SMI-32, and Nestin, at mRNA and protein levels. We could also quantitatively evaluate the expression of Islet-1, AChE, and Nestin at 14 days post-induction using flow cytometry. CONCLUSION: Human AD-MSCs are potent cells to differentiate into cholinergic-like cells in the presence of RA and Shh through a three-step protocol. Thus, they could be a suitable cell candidate for the regeneration of cholinergic-associated diseases. However, more functional and electrophysiological analyses are needed in this regard.

Molecular identification of Rhipicephalus species (Acari: Ixodidae) parasitizing livestock from Iran.

This study was designed to identify populations of Rhipicephalus sanguineus collected from Iran and also to study molecular taxonomy of Rhipicephalus species using cytochrome C oxidase subunit 1 (COI) and internal transcribed spacer 2 (ITS2) sequences. Tick specimens were collected from livestock (sheep and goat) in 14 Iranian provinces. DNA of individual specimens was extracted and PCR was done on these samples. So, 62 sequencing (33 COI and 29 ITS2) were done, successfully. Morphologically, we identified four Rhipicephalus species, namely R. bursa, R. sanguineus (s.l.), R. sanguineus (s.s.), and R. turanicus based on taxonomic keys. The data obtained from the phylogenetic analyses of COI and ITS2 fragments present a possible conflict regarding the identity of R. sanguineus species. Thus, the molecular identification of R. sanguineus group might be different according to mitochondrial and nuclear DNA. The results show a phylogenic conflict based on COI and ITS2 phylogeny in a tree topology. We dealt with three genetic entities in R. sanguineus group (i.e. R. sanguineus (s.s.), R. sanguineus (s.l.), and R. turanicus) based on COI phylogeny and two genetic clades (i.e. R. sanguineus (s.s.) and R. sanguineus (s.l.)/R. turanicus) according to ITS2 phylogeny.

Characterization of VvPAL-like promoter from grapevine using transgenic tobacco plants.

A 2000-bp 5'-flanking region of VvPAL-like was isolated from 'Summer Black' grapevine by PCR amplification, named pVvPAL-like. To gain a better understanding of the expression and regulatory mechanism of VvPAL-like, a chimeric expression unit consisting of the ß-glucuronidase (GUS) reporter gene under the control of a 2000-bp fragment of the VvPAL-like promoter was transformed into tobacco via Agrobacterium tumefaciens. Histochemical staining showed that the full-length promoter directs efficient expression of the reporter gene in cotyledons and hypocotyls, stigma, style, anthers, pollen, ovary, trichomes, and vascular bundles of transgenic plants. A series of 5' progressive deletions of the promoter revealed the presence of a negative regulatory region (-424 to -292) in the VvPAL-like promoter. Exposure of the transgenic tobacco plants to various abiotic stresses demonstrated that the full-length construct could be induced by light, copper (Cu), abscisic acid (ABA), indole-3-acetic (IAA), methyl jasmonate (MeJA) (N-1-naphthylphthalamic acid), ethylene, and drought. Furthermore, the ethylene-responsive region was found to be located in the -1461/-930 fragment, while the element(s) for the MeJA-responsive expression may be present in the -424/-292 region in the VvPAL-like promoter. These findings will help us to better understand the molecular mechanisms by which VvPAL-like participates in biosynthesis of flavonoids and stress responses.

Differentiation Potential of Human Chorion-Derived Mesenchymal Stem Cells into Motor Neuron-Like Cells in Two- and Three-Dimensional Culture Systems.

Many people worldwide suffer from motor neuron-related disorders such as amyotrophic lateral sclerosis and spinal cord injuries. Recently, several attempts have been made to recruit stem cells to modulate disease progression in ALS and also regenerate spinal cord injuries. Chorion-derived mesenchymal stem cells (C-MSCs), used to be discarded as postpartum medically waste product, currently represent a class of cells with self renewal property and immunomodulatory capacity. These cells are able to differentiate into mesodermal and nonmesodermal lineages such as neural cells. On the other hand, gelatin, as a simply denatured collagen, is a suitable substrate for cell adhesion and differentiation. It has been shown that electrospinning of scaffolds into fibrous structure better resembles the physiological microenvironment in comparison with two-dimensional (2D) culture system. Since there is no report on potential of human chorion-derived MSCs to differentiate into motor neuron cells in two- and three-dimensional (3D) culture systems, we set out to determine the effect of retinoic acid (RA) and sonic hedgehog (Shh) on differentiation of human C-MSCs into motor neuron-like cells cultured on tissue culture plates (2D) and electrospun nanofibrous gelatin scaffold (3D).

Differentiation potential of human bone marrow mesenchymal stem cells into motorneuron-like cells on electrospun gelatin membrane.

Human bone marrow-derived mesenchymal stem cells are potent types of cells with self renewal ability and immunomodulatory properties. They not only have the capacity to differentiate into mesodermal lineages, but they are also capable to transdifferentiate into neural cells in vitro and in vivo. From a biological point of view, the specification of cell fate in the central nervous system is largely dictated by retinoic acid and sonic hedgehog. In addition with inductive molecules, electrospun three dimensional (3D) scaffolds with similar properties to natural extracellular matrix represent a physiological environment that could better resemble the in vivo microenvironment in comparison with two dimensional culture systems. In this regard, the aim of this study was to examine whether induction of human BM-MSCs with retinoic acid (RA) and sonic hedgehog (Shh) in combination with electrospun gelatin scaffold could lead to better differentiation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) into motorneuron-like cells in vitro.

The Black Flies (Diptera: Simuliidae) of Iran.

Although Iran has a large geographic area encompassing 13 ecoregions, its simuliid fauna remains largely unexplored. To begin redressing this faunal gap, we reviewed literature records and coupled morphological and chromosomal identifications of material newly collected from 16 sites in Iran. Twenty-three nominal species are now recognized, including new country records for Simulium crassicaulum (Rubtsov) and Simulium alajense Rubtsov, and the southernmost world record for Simulium transcaspicum Enderlein. Multiple cytoforms of the Simulium aureum group, Simulium bezzii complex, and Simulium ornatum group were found.