Self-organization of developing embryo using scale-invariant approach

<p>Abstract</p> <p>Background</p> <p>Self-organization is a fundamental feature of living organisms at all hierarchical levels from molecule to organ. It has also been documented in developing embryos.</p> <p>Methods</p> <p>In this study, a scale-invariant power law (SIPL) method has been used to study self-organization in developing embryos. The SIPL coefficient was calculated using a centro-axial skew symmetrical matrix (CSSM) generated by entering the components of the Cartesian coordinates; for each component, one CSSM was generated. A basic square matrix (BSM) was constructed and the determinant was calculated in order to estimate the SIPL coefficient. This was applied to developing <it>C. elegans </it>during early stages of embryogenesis. The power law property of the method was evaluated using the straight line and Koch curve and the results were consistent with fractal dimensions (fd). Diffusion-limited aggregation (DLA) was used to validate the SIPL method.</p> <p>Results and conclusion</p> <p>The fractal dimensions of both the straight line and Koch curve showed consistency with the SIPL coefficients, which indicated the power law behavior of the SIPL method. The results showed that the ABp sublineage had a higher SIPL coefficient than EMS, indicating that ABp is more organized than EMS. The fd determined using DLA was higher in ABp than in EMS and its value was consistent with type 1 cluster formation, while that in EMS was consistent with type 2.</p

Creatine and retinoic acid effects on the induction of autophagy and differentiation of adipose tissue-derived stem cells into GABAergic-like neurons

BACKGROUND AND OBJECTIVE: Deficit of inhibitory GABAergic neurons as a part of central nervous system (CNS) pathogenesis was reported in neurodegenerative disorders; and adipose-derived stem cells (ADSCs) were shown to be a feasible option for cell transdifferentiation in neuronal disorders therapy. In this study, the role of autophagy in differentiation was considered by evaluating the expression of the autologous genes of LC3, P62 and GABARAP in fatty stem cells and after the pre-induction stage. METHODS: In this experimental study, under sterile conditions ADSCs were obtained from pararenal fat of two male adult rats. The cells were divided into three groups of fatty stem cells, pre-induction and induction. Following third passages of cell culture, ADSCs were preinduced to neural-like cells (NLCs) using 1mM β-mercaptoethanol (βME) and 10μM retinoic acid (RA), and then NLCs were induced by creatine(Cr) in 1, 5, 10, 20 millimolar for 5 days. In induction stage, the effects of creatine on differentiation were studied by anti nestin and GABA antibody immunostainig. The roles of GABARAP, LC3 and p62 autophagy genes in transdifferentiation were assessed by RT-PCR. FINDINGS: Immunocytochemical studies on ADSCs using CD49d indicated that cultured cells were ADSCs. In the immunochemical studies of the induction stage, at a dose of 10 mM creatinine for 5 days, the expression of the GABA neurons and the nestin-like neuronal cell marker were 58±2 and 56±5, respectively which had a significant difference with other doses and control group (p<0.05). RT-PCR results indicated that in pre-induced cells autophagy genes of GABARAP, LC3 and p62 were expressed but only P62 gene was expressed in fatty stem cells. CONCLUSION: This study demonstrated that fatty stem cells after induction are able to express nestin and GABA neuronal markers. GABARAP, LC3 and p62 autophagy genes were expressed in pre-induced cells, which indicates the potential role of autophagy in the differentiation of fatty stem cells into nerve-like cells. © 2017, Babol University of Medical Sciences. All rights reserved

Decrease in Cavity Size and Oligodendrocyte Cell Death Using Neurosphere-Derived Oligodendrocyte-Like Cells in Spinal Cord Contusion Model

Background: Oligodendrocyte cell death is among the important features of spinal cord injury, which appears within 15 min and occurs intensely for 4 h after injury, in the rat spinal contusion model. Accordingly, the number of oligodendrocytes progressively reduced within 24 h after injury. Administration of oligodendrocyte-like cells (OLCs) into the lesion area is one of the approaches to counterbalance this condition. Methods: Bone marrow stromal cells were transdifferentiated into neurospheres and then into neural stem cells and later were differentiated into OLCs using triiodothyronine and transplanted into the spinal cord contusion rats. The post-injury functional recovery was explored and compared with the control group using Basso-Beattie-Bresnahan and narrow beam behavioral tests. At the end of 12th week, spinal cord segments T12-L1 were histomorphologically studied by immunohistochemistry. Results: Motor improvement was more obvious during 2nd to 4th weeks and got less prominent during 4th to 12th weeks. Histomorphometric findings indicated that cavity formation decreased in epicenter of transplantation area in experimental groups in comparison with the control groups. Conclusion: The findings obtained in the present study showed that OLC therapy is a potential approach in the treatment of spinal cord traumatic injuries

Combined effects of 3D bone marrow stem cell-seeded wet-electrospun poly lactic acid scaffolds on full-thickness skin wound healing

© 2017 Taylor & Francis. Tissue engineering has emerged as an alternative treatment to traditional grafts for skin wound healing. Three-dimensional nanofibers have been used extensively for this purpose due to their excellent biomedical-related properties. In this study, high porous 3D poly lactic acid nanofibrous scaffolds (PLA-S) were prepared by wet-electrospinning technique and seeded with rat bone-marrow stem cells (BMSCs) to characterize the biocompatibility and therapeutic efficacy of these fibers on the treating full-thickness dermal wounds. The results of in vitro andin vivo studies indicate that the 3D fibrous PLA-S can be a potential wound dressing for wound repair, particularly when seeded with BMSCs. GRAPHICAL ABSTRACT

PuraMatrix hydrogel enhances the expression of motor neuron progenitor marker and improves adhesion and proliferation of motor neuron-like cells

Objective(s): Cell therapy has provided clinical applications to the treatment of motor neuron diseases. The current obstacle in stem cell therapy is to direct differentiation of stem cells into neurons in the neurodegenerative disorders. Biomaterial scaffolds can improve cell differentiation and are widely used in translational medicine and tissue engineering. The aim of this study was to compare the efficiency of two-dimensional with a three-dimensional culture system in their ability to generate functional motor neuron-like cells from adipose-derived stem cells. Materials and Methods: We compared motor neuron-like cells derived from rat adipose tissue in differentiation, adhesion, proliferation, and functional properties on two-dimensional with three-dimensional culture systems. Neural differentiation was analyzed by immunocytochemistry for immature (Islet1) and mature (HB9, ChAT, and synaptophysin) motor neuron markers. Results: Our results indicated that the three-dimensional environment exhibited an increase in the number of Islet1. In contrast, two-dimensional culture system resulted in more homeobox gene (HB9), Choline Acetyltransferase (ChAT), and synaptophysin positive cells. The results of this investigation showed that proliferation and adhesion of motor neuron-like cells significantly increased in three-dimensional compared with two-dimensional environments. Conclusion: The findings of this study suggested that three-dimension may create a proliferative niche for motor neuron-like cells. Overall, this study strengthens the idea that three-dimensional culture may mimic neural stem cell environment for neural tissue regeneration