Cell and Tissue Journal

Abstract Aim: Tissue engineering refers to methods that are based on the use of scaffolds, cells and biologically active molecules to produce tissues with specific functions. The purpose of tissue engineering is to build structures that can regenerate, maintain and improve damaged tissue or the whole organ. Today, by using tissue engineering methods, various natural and synthetic scaffolds have been designed that can be used for nerve grafts. The physical, chemical and biological properties of the scaffold must be similar to the extracellular matrix of the body in order to avoid adhesion, growth and support the differentiation of cells. An ideal neural scaffold should have biodegradability, biocompatibility and proper tensile strength. Recently, the use of polycaprolactan as a suitable biodegradable material has been evaluated in many fields of tissue engineering. Antioxidants are among the substances, which seem to be able to prevent neuronal death by reducing the amount of ROS. Flavonoids include many compounds that have various biological effects in the body. Silymarin (Silybum marianum) is a flavonoid that has many effects, including anti-cancer effects and antioxidant properties. Tragacanth is a known natural polymer that has excellent biological properties such as biodegradability, biocompatibility, antibacterial and wound healing ability. It is obtained from the stems and branches of the Asian species tragacanth. It has outstanding structural stability against heat and acidity. The aim of this study is to produce polycaprolactan/ tragacanth /silymarin nanoscaffolds and to investigate the viability of pc12 cells on the scaffold under oxidative stress. Considering that silymarin has antioxidant properties, the use of polycaprolactan/ tragacanth /silymarin nanoscaffolds can prevent neuropathy of nerve cells.
Material and Methods: Scaffolds used in this research were prepared using the electrophoretic method. For this purpose, an electrospinning machine was used, which is equipped with a rotary collector with a thickness of 70 mm and a width of 50 mm. In order to prepare a polycaprolactan/ tragacanth nanoscaffold and load silymarin on it, a 7% polycaprolactan solution (dissolved in acetic acid), 0.7% by weight tragacanth solution (dissolved in acetic acid) and 0.9% by weight silymarin solution were mixed by a magnetic stirrer for 20 minutes, and in order to make the solution uniform, sodium didecyl sulfate (SDS) with a concentration 1 percent by weight of the solvent was added to the solution and the suspension was homogenized for 20 minutes with an ultrasonic device, then the scaffold was prepared by an electrospinning device. . The nanofibers were collected in a period of 6 hours, the sample collection speed was 1 ml per hour, and the nanofiber samples were collected by rotating at 250 rpm. The distance between the injection needle and the scaffold is 12 cm and this process is done at a voltage of 15 kV. The morphology of the scaffold was evaluated by scanning electron microscope (SEM) and the chemical structure of the scaffold was evaluated by FTIR spectroscopy. To investigate the antioxidant properties of the scaffold, glucose 80 mg/L and H2O2, 150 macro L were used.
Results: Examining the morphology and chemical structure of the scaffold showed the proper porosity of the polycaprolactan/ tragacanth scaffold and the successful loading of silymarin on the scaffold. Evaluation of the oxidant properties of the scaffold after 24 hours of PC12 cell culture on it showed the increase in cell viability on the scaffold and the appropriate antioxidant properties of the scaffold.
Conclusion: The results of this research showed that the enrichment of polycaprolactan/ tragacanth scaffold with silymarin increased the proliferation and survival of PC12 cells under oxidative stress. Therefore, this scaffold can be a suitable candidate for tissue engineering in oxidative stress.

Abstract  
Aim: Tissue engineering is a new approach to regeneration and repair lost or damaged tissues. The aim of this study is to design and manufacture polycaprolactone (PCL) randomly electrospun nanofiber scaffold for use in regenerative medicine.
Material and Methods: Human adipose derived stem cells (hADSCs) were isolated (from superficial layer of abdominal fat), cultured (in DMEM/Ham'sF12 medium) and characterized (flow cytometry for CD29, CD73, CD34, CD105 and CD45). Electrospinning was used to produce PCL nanofiber scaffolds, scanning electron microscopy (SEM) was used to investigate the binding, penetration and morphology of hADSCs, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) was used to determine the toxicity of scaffolds.
Results: Flow cytometry showed extensive expression of the CD29, CD73 and CD105 (positive) and very low expression of the CD34 and CD45 (negative) in hADSCs. The results of MTT assay, showed the viability and proliferation of hADSCs which were seeded on the nanofiber scaffold. Microscopic photographs of SEM, showed hADSCs attached to PCL nanofiber scaffolds and migrating.
Conclusion: The results of this study showed that electrospun PCL nanofiber scaffolds are suitable for implantation, binding and propagation of hADSCs.

Abstract Aim: In this research, design and fabrication of graphene reinforced nano-composite scaffolds for neural induction in dental pulp stem cells (DPSCs) has been considered.
Material and methods: Polycaprolactone / nano-graphene composite scaffolds with 1%, 3% and 5% wt. graphene were firstly fabricated by the solvent casting method. Subsequently, hydrophilicity and electrical conductivity of the nano-composites were measured. According to the results of the mentioned physical experiments, the appropriate scaffold with the optimal ratio of nano-graphene was selected and cellular morphology, metabolic activity and neural differentiation potential of cultured DPSCs on it were evaluated by scanning electron microscopy (SEM), MTS assay and Immunofluorescent staining, respectively.
Results: Conductivity results demonstrated that by adding graphene to pure polymer, the electrical conductivity of the composite considerably increased. The addition of 5% wt. nano-graphene to the polymer can also reduce contact angle amount from 99.89±2.86° to 64.03±3.36°. Finally, SEM and Immunofluorescence images with MAP2 marker illustrated that the cultured cells on the surface of optimum scaffold differentiated into neuron-like cells with neural morphology.
Conclusion: The results of this study showed that conductive polycaprolactone containing 5% graphene nano-composite scaffolds have the appropriate potential for induction of neural differentiation and application in neural tissue engineering.
 
 

Abstract Aim: The aim of this study was to investigate the bovine chondrocytes growth on new polymeric nanofibers silk fibroin/kitosan  scaffolds, designed by authors,  to form the cartilage tissue.
Material and Methods: The chondrocyte cells isolated from three calf articular cartilage were loaded on the   scaffold. After a monthof  incubation, cells morphology was studied by SEM and the rate of cell growth by H&E and DAPI staining. To assay chondrogenesis in the culture, production of collagene was assayed by masson’s trichrom staining and formation of Glycosaminoglycans (GAGs) and  Proteoglycan was assayed by DMMB and “safranin O” staining.
Results: The results showed that the cells attached and proliferated to scaffolds very well. The number of cultured cells after one month proliferated by 4 to 5 times. Masson’s trichrom, safranin O staining and GAG assay showed cartilage tissue production in the scaffolds.
Conclusion: According to the results, the scaffold of nanofibers Fibroin silk / chitosan could be a good scaffold candidate for cartilage tissue engineering. This is due to the nature of the proteins in silk fibroin and polysaccharides in chitosan for cellular attachment and also the diameter close to the diameter of extracellular matrix proteins in these scaffolds.
 

Abstract Aim: The aim of this study was to evaluate the biocompatibility and differentiation of human umbilical cord mesenchymal stem cells to osteoblast on prepared polycaprolactone scaffolds by electrospinning method, which is located under the surface modification by oxygen plasma.
Material and methods: After isolation of mesenchymal stem cells from human umbilical cord, flow cytometry analysis was performed. Biocompatibility of scaffold was examined using MTT assay. Cells morphology and their adhesion characteristics on the scaffold surface were studied using Scanning Electron Microscopic (SEM) images. Also biodegradability of scaffold calculated using weight loss method. Finally, for study the differentiation of cells on the scaffold surface, osteogenic differentiation medium was used and differentiation was performed by red alizarin staining and RT-PCR.
Results: Results showed that the cells not only had more suitable connection and reproduction abilities on the scaffold, but also were morphologically in a natural condition. Polycaprolacton scaffold is enjoyment of high biocompatibility and its biodegradability up to 15th day done with more rates in comparison with 15 next days. Also red alizarin staining and RT-PCR results showed high rate cell differentiation on polycaprolactone scaffold.
Conclusion: The obtained results of this research suggested that polycaprolactone scaffolds have potential usage as biocompatible biomaterials in tissue engineering and osteogenic differentiation applications.

Abstract Aim: In this study, it was done to evaluate the efficiency of both PRP and Fibrin Glue scaffolds in producing suitable environment for the growth of mesenchymal stem cells.
Material and Methods: In this study, the preparation of PRP and Fibrin Glue Scaffold were carry out and Mesenchymal Stem Cells (MSCs) isolated from adipose tissue. The mesenchymal phenotype of these cells was determined by mesenchymal surface marker using flow cytometry. Then, MSCs were cultured, and on the third passage (P3)stage, they were seeded separately on the two scaffolds and after 48 hours of cell culture, the ability of the scaffolds seeded cells was evaluated by MTT assay for cells viability.
Results:Flow cytometry results showed that human adipose-derived mesenchymal stem cell expressed CD44, CD90 and CD105 surface markers. Also, the results of this study showed that the active PRP could be creating a more suitable environment for the survival and proliferation of mesenchymal stem cells in compare with Fibrin glue
Conclusion:It is suggested that the PRP as a protective scaffold could be used for mesenchymal stem cells growth to provide effective strategies in order to tissue engineering development and regenerative medicine.

Abstract Aim: In this study we were investigated the importance of the preparation method of the substrate based on PLGA polymer by electrospinning and freeze-drying method. To investigate the effect of nanotopogeraphy on cell behavior, the prepared nanofibers were compared with each other in three speeds of the collector.
Material & Methods: PLGA substratums were made by electrospinning and freeze-dying. The morphology of the structures was compared by use of the Scanning electron microscope images. Mouse fibroblast cells (L929 cell line) were seeded on substrates to determine the cell viability and followed by MTT assay.
Results: Scanning electron microscope images showed that, by increasing the speed of collector, the nanofibrous orientation increased. MTT assay (p < 0.05) showed in 24 h that PLGA substrates prepared by freeze-drying method were provided the appropriate attachment for the cell by producing a porous structure. Cell viability was significantly increased on the PLGA nanofibers with increase of fibers regularity after 48 and 72 h cell culture. This feature did not change on freeze-drying substrate.
Conclusion: The findings were indicated that electrospun PLGA nanofibers had the better performance to provide cell behavior. It was expected because of similarity to the structure of the natural extracellular matrix. It seems that aligned fibers acted as a positive factor to support cell proliferation.

Abstract Aim: The main goal of this research was to prepare a three-dimensional matrix from gingival palate tissues and investigate the possible application of this scaffold ​​in cell culture and tissue engineering.
Materials and methods: In order to fabricate the scaffolds, the biopsy samples of human palate gingival tissue were preparated surgically and divided in 5 groups then decellulization of the samples were carried out via physical method (put in nitrogen tanks and rinsing with distilled water) as well as chemical method using different concentrations of SDS (0.1%, 0.25%, 0.5%, 0.75% and 1%). Furthermore to evaluate the scaffold prepared with 1% SDS, embryonic like cells from blastema tissue were seeded on the three-dimensional scaffold.
Results: Concentration of SDS below 0.5% caused significant reduction (p < 0.05) of decellulization of the tissues. Microscopic studies of blastema tissue on the scaffold in different days revealed the penetration, migration, adhesion and differentiation of the cells.
Conclusion: This study showed that, it is possible to prepare a natural scaffold frome palatal gingiva tissue using SDS treatment. On the other hand, the results of histologic studies showed that the decellulized scaffolds of palatal gingival might be suitable as three-dimensional bioscaffold for movement, adhesion, differentiation and migration of cells. More investigation is needed to determine the identity of the differentiated cells which further it can help to improve our knowledge about cell-matrix interaction.