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Introduction: Biocompatible and biodegradable scaffolds have gained tremendous attention because of their potential in tissue engineering. In this study, the aim was to reach a feasible setup from a ternary hybrid of polyaniline (PANI), gelatin (GEL), and polycaprolactone (PCL) to fabricate aligned and random nanofibrous scaffolds by electrospinning for tissue engineering purposes. Methods: Different setups of PANI, PCL, and GEL were electrospun. Then, the best aligned and random scaffolds were chosen. SEM imaging was done to observe nanoscaffolds before and after stem cell differentiation. Mechanical properties of the fibers were tested. Their hydrophilicity was measured using the sessile drop method. SNL Cells were then seeded onto the fiber, and MTT was performed to assess its toxicity. The cells were then differentiated. After osteogenic differentiation, alkaline phosphatase activity, calcium content assay, and alizarin red staining were done to check the validity of osteogenic differentiation. Results: The two chosen scaffolds had an average diameter of 300 ± 50 (random) and 200 ± 50 (aligned). MTT was performed and its results showed that the scaffolds were non-toxic to cells. After stem cell differentiation, alkaline phosphatase activity was performed, confirming differentiation on both types of scaffolds. Calcium content and alizarin red staining also confirmed stem cell differentiation. Morphological analysis showed no difference regarding differentiation on either type of scaffold. However, unlike on the random fibers, cells followed a specific direction and had a parallel-like growth pattern on aligned fibers. Conclusion: All in all, PCL-PANI-GEL fibers showed to be capable candidates for cell attachment and growth. Furthermore, they proved to be of excellent use in bone tissue differentiation.
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Nanofiber scaffolds and bio-ceramic nanoparticles have been widely used in bone tissue engineering. The use of human- induced pluripotent stem cells (hiPSCs) on this scaffold can be considered as a new approach in the differentiation of bone tissue. In the present study, a polyaniline-gelatin-polycaprolactone (PANi-GEL-PCL) composite nanoscaffold was made by electrospinning and modified superficially by plasma method. The synthesized nanoscaffold was then coated with willemite's bio-ceramic nanoparticles (Zn2SiO4). The nanoscaffold's properties were studied by scanning electron microscopy (SEM). Also, nanoparticles characterization was carried out with SEM and dynamic light scattering. The growth and proliferation rate of cells on the synthesized nanoscaffold was examined by MTT assay. Subsequently, hiPSCs were cultured on murine fibroblast cells, incubated in embryoid bodies for 3 days, and placed on the nanoscaffolds. The differentiation potential of hiPSCs was investigated by the examination of common bone markers (e.g. alkaline phosphatase, calcium salt precipitation, and alizarin red test) using bone differentiation factors for 14 days. SEM showed the proper structure of electrospinned nanoscaffolds and coating of nanoparticles on the nanoscaffold surface. The results of MTT assay confirmed the growth and proliferation of cells and the biocompatibility of nanofibers. The results of bone indices also showed that differentiation on the composite nanoscaffold coated with willemite's bio-ceramic nanoparticles dramatically increased in comparison with other groups. Overall, this study demonstrated that PANi-GEL-PCL composite nanoscaffold with willemite's bio-ceramic nanoparticles is a suitable substrate for in vitro growth, proliferation, and differentiation of hiPSCs cells into osteoblasts.
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Background: Multiple sclerosis (MS) and neuromyelitis optica (NMO) are both demyelinating disorders and oxidative stress is suggested to have a role in their pathogenesis. Glucose-6-phosphate dehydrogenase (G6PD) produces nicotinamide adenine dinucleotide phosphate (NADPH) via the pentose phosphate pathway. NADPH is not only involved in the synthesis of fatty acids necessary for myelination, but also it is involved in the defense against oxidative stress. Prescribing supplementary vitamin D as a part of the MS treatment plan can increase G6PD gene expression. The aim of this study was to determine the serum level of G6PD in patients with MS and NMO and its relationship with vitamin D, since it is yet to be explored thoroughly. Methods: In this case-control study, subjects were divided into three experimental and control groups. The experimental groups comprised 50 patients with relapsing-remitting MS (RRMS) who had a history of vitamin D consumption, 50 newly-diagnosed MS patients, and 50 patients with NMO. Control group included 65 healthy individuals. Serum level of G6PD was measured and compared among these groups. Results: No significant difference was seen between the G6PD level in patients with MS and NMO, but it should be noted that this level was significantly lower than the healthy group. G6PD serum level was significantly higher in patients with MS who had previously consumed supplementary vitamin D compared to those who had not. Conclusion: G6PD deficiency is observed in patients with MS and NMO. Also, supplementary vitamin D may induce favorable results on the G6PD level.