Astaxanthin as an Anticancer Agent against Breast Cancer: An In Vivo and In Vitro Investigation.

AIM: This study aimed to investigate the antioxidant properties, cytotoxic activity, and apoptotic effects of astaxanthin (ASX) on genes and pathways involved in breast cancer in Balb/c mice models injected with the 4T1 cell line. BACKGROUND: ASX could inhibit some tumor progression by using in vivo and in vitro models. OBJECTIVE: The effect of ASX on breast cancer was not fully understood till now. METHOD: In an in vivo model, 4T1 cells-injected mice were administered with different concentrations of ASX (100 and 200 mg/kg), and histopathological evaluations were done using an optical microscope and the hematoxylin and eosin (H&E) staining. The real- time PCR investigated the expression levels of B-cell lymphoma 2-associated X (Bax), B-cell lymphoma 2 (Bcl-2), and Caspase 3 genes in mice treated with 100 and 200 mg/kg ASX. Also, the level of superoxide dismutase (SOD) and malondialdehyde (MDA) were examined in ASX-treated cancer mice. RESULTS: ASX (200 mg/kg) caused a significant reduction in the mitotic cell count of tumor tissues compared to ASX (100 mg/kg). The antiproliferative effects of different concentrations of ASX were shown based on the MTT results. The treatment of breast tumor mice with both concentrations of ASX, especially 200 mg/kg, elevated the expression of Caspase 3, Bax, and SOD enzyme levels and decreased Bcl-2 expression and MDA enzyme levels. CONCLUSION: ASX can be considered a promising alternative treatment for breast cancer.

Anticancer activity of thymoquinone against breast cancer cells: Mechanisms of action and delivery approaches.

The rising incidence of breast cancer has been a significant source of concern in the medical community. Regarding the adverse effects and consequences of current treatments, cancers' health, and socio-economical aspects have become more complicated, leaving research aimed at improved or new treatments on top priority. Medicinal herbs contain multitarget compounds that can control cancer development and advancement. Owing to Nigella Sativa's elements, it can treat many disorders. Thymoquinone (TQ) is a natural chemical derived from the black seeds of Nigella sativa Linn proved to have anti-cancer and anti-inflammatory properties. TQ interferes in a broad spectrum of tumorigenic procedures and inhibits carcinogenesis, malignant development, invasion, migration, and angiogenesis owing to its multitargeting ability. It effectively facilitates miR-34a up-regulation, regulates the p53-dependent pathway, and suppresses Rac1 expression. TQ promotes apoptosis and controls the expression of pro- and anti-apoptotic genes. It has also been shown to diminish the phosphorylation of NF-B and IKK and decrease the metastasis and ERK1/2 and PI3K activity. We discuss TQ's cytotoxic effects for breast cancer treatment with a deep look at the relevant stimulatory or inhibitory signaling pathways. This review discusses the various forms of polymeric and non-polymeric nanocarriers (NC) and the encapsulation of TQ for increasing oral bioavailability and enhanced in vitro and in vivo efficacy of TQ-combined treatment with different chemotherapeutic agents against various breast cancer cell lines. This study can be useful to a broad scientific community, comprising pharmaceutical and biological scientists, as well as clinical investigators.

Chitosan, polyethylene oxide/polycaprolactone electrospun core/shell nanofibrous mat containing rosuvastatin as a novel drug delivery system for enhancing human mesenchymal stem cell osteogenesis.

Introduction: Due to the potential positive effects of rosuvastatin (RSV) on human mesenchymal stem cells (MSCs) osteogenesis and new bone regeneration, it is crucial to develop a suitable carrier that can effectively control the release profile of RSV. The primary objective of this study was to introduce a novel drug delivery system based on core/shell nanofibrous structures, enabling a sustained release of RSV. Methods: To achieve this, coaxial electrospinning was employed to fabricate chitosan (CS)+polyethylene oxide (PEO)/polycaprolactone (PCL) nanofibrous mats, wherein RSV was incorporated within the core of nanofibers. By optimizing the relevant parameters of the electrospinning process, the mats' surface was further modified using plasma treatment. The fibers' shape, structure, and thermal stability were characterized. The wettability, and degradation properties of the fabricated mats were also examined. In vitro studies were conducted to examine the release behavior of RSV. Additionally, the capability of MSCs to survive and differentiate into osteocytes when cultured on nanofibers containing RSV was evaluated. Results: Results demonstrated the successful fabrication of CS + PEO + RSV/PCL core/shell mats with a core diameter of approximately 370 nm and a shell thickness of around 70 nm under optimized conditions. Plasma treatment was found to enhance the wettability and drug-release behavior of the mats. The nanofibrous structure, serving as a carrier for RSV, exhibited increased proliferation of MSCs and enhanced osteogenic differentiation. Conclusion: Therefore, it can be concluded that CS + PEO + RSV/PCL core/shell nanofibrous structure can be utilized as a sustained-release platform for RSV over an extended period, making it a promising candidate for guided bone regeneration.

Genetic attributes of Iranian cystic fibrosis patients: the diagnostic efficiency of CFTR mutations in over a decade.

Objectives: Cystic fibrosis (CF) is the most prevalent autosomal recessive disorder among Caucasians. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause this pathology. We, therefore, aimed to describe the CFTR mutations and their geographical distribution in Iran. Method: The mutation spectrum for 87 families from all Iranian ethnicities was collected using ARMS PCR, Sanger sequencing, and MLPA. Results: Mutations were identified in 95.8% of cases. This dataset revealed that the most frequent mutations in the Iranian population were F508del, c.1000C>T, c.1397C>G, c.1911delG, and c.1393-1G>A. In addition, we found weak evidence for Turkey being the possible geographical pathway for introducing CFTR mutations into Iran by mapping the frequency of CFTR mutations. Conclusion: Our descriptive results will facilitate the genetic detection and prenatal diagnosis of cystic fibrosis within the Iranian population.

Evaluation of Lactobacillus plantarum and PRGF as a new bioactive multi-layered scaffold PU/PRGF/gelatin/PU for wound healing.

The effect of tissue engineering strategies in combination with Lactobacillus plantarum and platelet-rich growth factor (PRGF) with the aim of creating an appropriate wound dressing can be useful in wound healing and infection prevention in patients suffering from acute and chronic skin damages. Therefore, in this study, a new approach was employed to create a bioactive multilayer electrospun scaffold composed of polyurethane (PU), PRGF, and gelatin fibers, then human adipose-derived mesenchymal stem cells (hAMSCs), fibroblast cells (HU-02) and L. plantarum were cultured on the scaffold. The physicochemical properties, biocompatibility, and antibacterial activity of the scaffold were evaluated. In addition, the expression of the migration and proliferation genes of fibroblast cells were investigated by real-time PCR (polymerase chain reaction). Mitochondrial activity assays revealed that PRFG and L. plantarum had a significant positive effect on the viability of target co-cultured cells.Fluorescent and SEM (scanning electron microscopy) images presented the cells and bacterial proliferation and adhesion in hydrophilic scaffolds within 21 days. The sustained release of PRGF from scaffolds with a zero-order pattern was confirmed. RT-PCR analysis revealed that PRGF elevated the expression of VEGF genes up to fourfold, but L. plantarum had a better effect on DDR2 gene expression compared to the TCPS group. Antibacterial tests showed that L. plantarum has a bacterial load reduction of more than 70% in CFU/mL. The present scaffold is an appropriate model for cell attachment, migration, proliferation, and infection prevention.

The miR-429 suppresses proliferation and migration in glioblastoma cells and induces cell-cycle arrest and apoptosis via modulating several target genes of ERBB signaling pathway.

BACKGROUND: Glioblastoma multiforme (GBM) is an aggressive and lethal brain cancer, which is incurable with standard cancer treatments. miRNAs have great potential to be used for gene therapy due to their ability to modulate several target genes simultaneously. We found miR-429 is downregulated in GBM and has several predicted target genes from the ERBB signaling pathway using bioinformatics tools. ERBB is the most over-activated genetic pathway in GBM patients, which is responsible for augmented cell proliferation and migration in GBM. METHODS AND RESULTS: Here, miR-429 was overexpressed using lentiviral vectors in U-251 and U-87 GBM cells and it was observed that the expression level of several oncogenes of the ERBB pathway, EGFR, PIK3CA, PIK3CB, KRAS, and MYC significantly decreased, as shown by real-time PCR and western blotting. Using the luciferase assay, we showed that miR-429 directly targets MYC, BCL2, and EGFR. In comparison to scrambled control, miR-429 had a significant inhibitory effect on cell proliferation and migration as deduced from MTT and scratch wound assays and induced cell-cycle arrest and apoptosis in flow cytometry. CONCLUSIONS: Altogether, miR-429 seems to be an efficient suppressor of the ERBB genetic signaling pathway and a potential therapeutic for GBM.

Reporting Two Novel Mutations in Two Iranian Families with Cystic Fibrosis, Molecular and Bioinformatic Analysis

Background: Cystic fibrosis (CF) is the most common heredity disease among the Caucasian population. More than 350 known pathogenic variations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene (NM_000492.4) cause CF. Herein, we report the outcome of our investigation in two unrelated Iranian families with CF patients. Methods: We conducted phenotypic examination, segregation, linkage analysis, and CFTR gene sequencing to define causative mutations. Results: We found two novel mutations in the present study. The first one was a deletion causing frameshift, c.299delT p.(Leu100Profs*7), and the second one was a missense mutation, c.1857G>T, at nucleotide binding domain 1 of the CFTR protein. Haplotype segregation data supported our new mutation findings. Conclusion: Findings of this study expand the spectrum of CFTR pathogenic variations and can improve prenatal diagnosis and genetic counseling for CF.

Prediction and validation of avascular tumor growth pattern in different metabolic conditions using in silico and in vitro models.

Objectives: In recent years, scientists have taken many efforts for in vitro and in silico modeling of cancerous tumors. In fact, three-dimensional (3D) cultures of multicellular tumor spheroids (MCTSs) are good validators for computational results. The goal of this study is to simulate the 3D early growth of avascular tumors using MCTSs and to compare the in vitro models with the results and predictions of a specific computational modeling framework. Using these two types of models, the importance of metabolic condition on tumor growth behavior and necrosis could be predicted. Materials and methods: We took advantage of a previously developed computational model of tumor growth (constructed by integrating a generic metabolic network model of cancer cells with a multiscale agent-based framework). Among the computational predictions is the importance of glucose accessibility on tumor growth behavior. To study the effect of glucose concentration experimentally, MCTSs were grown in high and low glucose culture media. After that, tumor growth pattern was analyzed by MTT assay, cell counting and propidium iodide (PI) staining. Results: We obviously observed that the rate of necrosis increases and the rate of tumor growth and cell activity decreases as the glucose availability reduces, which is in line with the computational model prediction.

Chitosan/PEO nanofibers containing Calendula officinalis extract: Preparation, characterization, in vitro and in vivo evaluation for wound healing applications.

Wound healing is a complex pathophysiological process, highlighting the importance of effective and thorough wound care along with the prevention of wound infection, a major barrier that can slow down or even disrupt the healing process. To date, there are plenty of herbal plants well known and historically supernatural, showing profound wound healing effects. Application of such herbal extracts/ingredients in electrospun nanofiber platforms has shown promising outcomes in improving wound healing process. Based on these facts, we loaded Calendula officinalis extract (CO) in chitosan/polyethylene oxide scaffolds (CS/PEO) by electrospinning. Using SEM, morphology of electrospun scaffolds showed a narrow range of fiber diameter, around 143--252 nm, with uniform and bead-free appearance. FT-IR spectroscopy confirmed the presence of CO extract in nanofibrous scaffolds. Of importance, incorporation of CO extract improved mechanical properties of CS/PEO nanofibers. A 1602 cP reduction in viscosity and a 0.892 ms/cm increase in the conductivity of the solution was observed after addition of the CO extract. CO extract showed strong antibacterial properties with 96% and 94% reduction in Gram positive and Gram negative bacteria, respectively. In vitro studies with fibroblast cells confirmed enhanced proliferation, growth and attachment of the cells. The in vivo and histological analysis of rat wounds, revealed excellent wound healing ability of CS/PEO/CO dressings (87.5 % wound closure after 14 days) via improving collagen synthesis, re-epithelization and remodeling of the tissue. In sum, our findings show that CS/PEO/CO scaffolds can be used as a promising dressing for the treatment of skin wounds.

miR-424 induces apoptosis in glioblastoma cells and targets AKT1 and RAF1 oncogenes from the ERBB signaling pathway.

Glioblastoma is a lethal and incurable cancer. Tumor suppressor miRNAs are promising gene therapy tools for cancer treatment. In silico, we predicted miR-424 as a tumor suppressor. It had several target genes from the epidermal growth factor receptor (ERBB) signaling pathway that are overactive in most glioblastoma cases. We overexpressed miR-424 by lentiviral transduction of U-251 and U-87 glioblastoma cells confirmed with fluorescent microscopy and real-time quantitative PCR (qRT-PCR). Then the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) proliferation assay and scratch wound migration assay were performed to investigate the miR-424 tumor suppressor effect in glioblastoma. miR-424's effect on glioblastoma apoptosis and cell-cycle arrest was verified using Annexin V- phosphatidylethanolamine (PE) and 7-minoactinomycin D (7-AAD) apoptosis assay and cell-cycle assay. miR-424 predicted target genes mRNA and protein level were measured after miR-424 overexpression in comparison to the control group by qRT-PCR and western blotting, respectively. We confirmed miR-424 direct target genes by dual-luciferase reporter assay. miR-424 overexpression significantly suppressed cell proliferation and migration rate in glioblastoma cells based on the MTT and scratch assays. Flow cytometry results confirmed that miR-424 promotes apoptosis and cell-cycle arrest in glioblastoma cells. Predicted target genes of miR-424 from the ERBB pathway were downregulated by miR-424 overexpression. qRT-PCR and western blotting showed that KRAS, RAF1, MAP2K1, EGFR, PDGFRA, AKT1, and mTOR mRNA expression levels and KRAS, RAF1, MAP2K1, EGFR, and AKT1 protein level, respectively, had significantly decreased as a result of miR-424 overexpression in comparison to the control group. Dual-luciferase reporter assay confirmed that miR-424 directly targets RAF1 and AKT1 oncogenes. Overall, miR-424 acts as tumor suppressor miRNA in glioblastoma cells.

Optimization of Nanoclay/Polyacrylonitrile Scaffold Using Response Surface Method for Bone Differentiation of Human Mesenchymal Stem Cells.

Response surface methodology (RSM) based on the D-optimal algorithm was employed here for the electrospinning of nanoclay/polyacrylonitrile (PAN) composite scaffold by the aim of obtaining the lower fiber diameter and better mechanical properties for bone regeneration. The input parameters included the electrospinning voltage, flow rate and the ratio of nanoclay/PAN and the obtained values for the optimum point were 17 kV for the applied voltage, 0.41 ml/hr for flow rate, and 19.06% for the nanoclay/PAN ratio. The composite scaffold was fabricated in accordance with these optimum values and then studied by scanning electron microscopy and tensile apparatus. The fiber diameter and Young's modulus of the prepared scaffold were respectively 145 ± 12 nm and 267 ± 8.7 MPa that the values were between predicted by RSM. Moreover, the biocompatibility and osteogenic differentiation of the composite scaffold were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and alkaline phosphatase assays. The bare scaffold and tissue culture polystyrene were used as control groups. The results approved stronger bioactivity and bone regeneration with the composite scaffold as a presence of clay nanoparticles.

Hyperosmolarity benefits cartilage regeneration by enhancing expression of chondrogenic markers and reducing inflammatory markers.

Application of hyperosmolarity can be a promising strategy to promote chondrogenic differentiation in adipose-derived mesenchymal stem cells (ADSCs). Growth factors may promote different signaling pathways in parallel that is why in this study we monitor undesired pathologic or unwanted side effects as well as chondroinductive impacts of hyperosmolarity in differentiating ADSCs. Quantified gene expression, immunocytochemistry, glycosaminoglycan deposition and angiogenic secretion assays performed along with immunoassay. We observed that hyperosmolarity pressure of 480 mOsm over-expressed cartilage specific markers at gene expression level in the extra cellular matrix. Meanwhile, hyperosmolarity of 480 mOsm diminished the expression of cartilage associated pathologic markers, i.e., inflammatory and angiogenic attributes. Certain dose of hyperosmolarity could benefit chondrogenesis in a dual way, first by increasing chondrogenic markers and second by lowering tissue mineralization and angiogenic potential. The chondroprotective potential of hyperosmolarity could have a promising benefit in cartilage cell therapy and tissue engineering.

Metagenomic discovery and functional validation of L-asparaginases with anti-leukemic effect from the Caspian Sea.

By screening 27,000 publicly available prokaryotic genomes, we recovered ca. 6300 type I and ca. 5200 type II putative L-asparaginase highlighting the vast potential of prokaryotes. Caspian water with similar salt composition to the human serum was targeted for in silico L-asparaginase screening. We screened ca. three million predicted genes of its assembled metagenomes that resulted in annotation of 87 putative L-asparaginase genes. The L-asparagine hydrolysis was experimentally confirmed by synthesizing and cloning three selected genes in E. coli. Catalytic parameters of the purified enzymes were determined to be among the most desirable reported values. Two recombinant enzymes represented remarkable anti-proliferative activity (IC50 <1IU/ml) against leukemia cell line Jurkat while no cytotoxic effect on human erythrocytes or human umbilical vein endothelial cells was detected. Similar salinity and ionic concentration of the Caspian water to the human serum highlights the potential of secretory L-asparaginases recovered from these metagenomes as potential treatment agents.

The applications of heparin in vascular tissue engineering.

Cardiovascular diseases, among all diseases, are taking the most victims worldwide. Coronary artery occlusion, takes responsibility of about 30% of the yearly global deaths in the world (Heart Disease and Stroke Statistics 2017 At-a-Glance, 2017), raising the need for viable substitutes for cardiovascular tissues. Depending on a number of factors, blocked coronary arteries are now being replaced by autografts or stents. Since the autografts, as the gold standard coronary artery replacements, are not available in adequate quality and quantity, the demand for small diameter vascular substitute comparable to native vessels is rapidly growing. Synthetic grafts have been successfully approved for developing vascular replacements but regarding the special conditions in small-caliber vessels, their use is limited to large-diameter vascular tissue engineering. The major problems associated with the vascular tissue engineered grafts are thrombosis and intimal hyperplasia. Heparin, a negatively charged natural polysaccharide has been used in fabricating vascular grafts since it prevents protein fouling on the surfaces and most importantly, impeding thrombosis. Herein, we focused on heparin, as a multifunctional bioactive molecule that not only serves as an anticoagulant with frequent clinical use but also acts as an anti-inflammatory and angiogenic regulatory substance. We summarized heparin incorporation into stents and grafts and their applicability to restrain restenosis. Also, the applications of heparinzation of biomaterials and heparin mimetic polymers and different approaches invoked to improve heparin bioactivity have been reviewed. We summarized the methods of adding heparin to matrices as they were explained in the literature. We reviewed how heparin influences the biocompatibility of the scaffolds and discussed new advances about using heparin in small-diameter vascular tissue engineering.

Combination of low intensity electromagnetic field with chondrogenic agent induces chondrogenesis in mesenchymal stem cells with minimal hypertrophic side effects.

Background: There are different methods to develop in vitro neo-chondral tissues from adipose-derived stem cells (ADSCs). Application of electromagnetic field (EMF) on ADSCs is one of popular approaches, which results in chondrogenesis. If chondrogenic impact of EMF on ADSCs is supposed to be generalized as a protocol in translational medicine field, possible emergence of early or late hypertrophic maturation, mineralization and inflammatory side effects in chondrogenically differentiating ADSCs should be considered.Methods: The advent of chondrogenic and hypertrophic markers by differentiated cells under standard, platelet-rich plasma (PRP)-based or EMF treatments were monitored. Along with monitoring the expressions of chondrogenic markers, inflammatory and hypertrophic markers, VEGF/TNFα secretion, calcium deposition and ALP activity were evaluated.Results: Accordingly, treatment with %5 PRP results in higher GAG production, enhanced SOX9 transcription, lowered TNFα and VEGF secretions compared to other treatments. Although PRP up-regulates miR-146a and miR-199a in early and late stages of chondrogenesis, respectively, application of EMF + PRP down regulates miR-101 and -145 while up-regulates miR-140 and SOX9 expression.Conclusion: Comparing our results with previous reports suggests that presented EMF-ELF in this study with f = 50 Hz, EMF intensity of less than 30 mT, and 5% PRP (v/v), would facilitate chondrogenesis via mesenchymal stem cells with minor inflammation and hypertrophic maturation.Abbreviations: MSCs: mesenchymal stem cells; TGFß: transforming growth factor-beta; PRP: platelet-rich plasma; ELF-EMF: extremely low-frequency electromagnetic fields; GAGs: glycosaminoglycans; ADSCs: adipose-derived stem cells; VEGF: vascular endothelial growth factor; TNFα: tumor necrosis factor alpha; ALP: alkaline phosphatase.

Comparative impact of platelet rich plasma and transforming growth factor-ß on chondrogenic differentiation of human adipose derived stem cells.

Introduction: Transforming growth factor-beta (TGF-ß) is known as standard chondrogenic differentiation agent, even though it comes with undesirable side effects such as early hypertrophic maturation, mineralization, and secretion of inflammatory/angiogenic factors. On the other hand, platelet-rich plasma (PRP) is found to have a chondrogenic impact on mesenchymal stem cell proliferation and differentiation, with no considerable side effects. Therefore, we compared chondrogenic impact of TGF-ß and PRP on adipose-derived stem cells (ADSCs), to see if PRP could be introduced as an alternative to TGF-ß. Methods: Differentiation of ADSCs was monitored using a couple of methods including glycosaminoglycan production, miRNAs expression, vascular endothelial growth factor (VEGF)/tumor necrosis factor alpha (TNFα) secretion, alkaline phosphatase (ALP) and calcium content assays. Results: Accordingly, the treatment of differentiating cells with 5% (v/v) PRP resulted in higher glycosaminoglycan production, enhanced SOX9 transcription, and lowered TNFα and VEGF secretion compared to the control and TGF-ß groups. Besides, the application of PRP to the media up-regulated miR-146a and miR-199a in early and late stages of chondrogenesis, respectively. Conclusion: PRP induces in vitro chondrogenesis, as well as TGF-ß with lesser inflammatory and hypertrophic side effects.

A critical role for miR-184 in the fate determination of oligodendrocytes.

BACKGROUND: New insights on cellular and molecular aspects of both oligodendrocyte (OL) differentiation and myelin synthesis pathways are potential avenues for developing a cell-based therapy for demyelinating disorders comprising multiple sclerosis. MicroRNAs (miRNA) have broad implications in all aspects of cell biology including OL differentiation. MiR-184 has been identified as one of the most highly enriched miRNAs in oligodendrocyte progenitor cells (OPCs). However, the exact molecular mechanism of miR-184 in OL differentiation is yet to be elucidated. METHODS AND RESULTS: Based on immunochemistry assays, qRT-PCR, and western blotting findings, we hypothesized that overexpression of miR-184 in either neural progenitor cells (NPCs) or embryonic mouse cortex stimulated the differentiation of OL lineage efficiently through regulating crucial developmental genes. Luciferase assays demonstrated that miR-184 directly represses positive regulators of neural and astrocyte differentiation, i.e., SOX1 and BCL2L1, respectively, including the negative regulator of myelination, LINGO1. Moreover, blocking the function of miR-184 reduced the number of committed cells to an OL lineage. CONCLUSIONS: Our data highlighted that miR-184 could promote OL differentiation even in the absence of exogenous growth factors and propose a novel strategy to improve the efficacy of OL differentiation, with potential applications in cell therapy for neurodegenerative diseases.

Vascular tissue engineering: Fabrication and characterization of acetylsalicylic acid-loaded electrospun scaffolds coated with amniotic membrane lysate.

As the incidence of small-diameter vascular graft (SDVG) occlusion is considerably high, a great amount of research is focused on constructing a more biocompatible graft. The absence of a biocompatible surface in the lumen of the engineered grafts that can support confluent lining with endothelial cells (ECs) can cause thrombosis and graft failure. Blood clot formation is mainly because of the lack of an integrated endothelium. The most effective approach to combat this problem would be using natural extracellular matrix constituents as a mimic of endothelial basement membrane along with applying anticoagulant agents to provide local antithrombotic effects. In this study, we fabricated aligned and random electrospun poly-L-lactic acid (PLLA) scaffolds containing acetylsalicylic acid (ASA) as the anticoagulation agent and surface coated them with amniotic membrane (AM) lysate. Vascular scaffolds were structurally and mechanically characterized and assessed for cyto- and hemocompatibility and their ability to support endothelial differentiation was examined. All the scaffolds showed appropriate tensile strength as expected for vascular grafts. Lack of cytotoxicity, cellular attachment, growth, and infiltration were proved using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and scanning electron microscopy. The blood compatibilities of different scaffolds examined by in vitro hemolysis and blood coagulation assays elucidated the excellent hemocompatibility of our novel AM-coated ASA-loaded nanofibers. Drug-loaded scaffolds showed a sustained release profile of ASA in 7 days. AM-coated electrospun PLLA fibers showed enhanced cytocompatibility for human umbilical vein ECs, making a confluent endothelial-like lining. In addition, AM lysate-coated ASA-PLLA-aligned scaffold proved to support endothelial differentiation of Wharton's jelly-derived mesenchymal stem cells. Our results together indicated that AM lysate-coated ASA releasing scaffolds have promising potentials for development of a biocompatible SDVG.

Polyethylenimine: A new differentiation factor to endothelial/cardiac tissue.

Among different tissues, endothelial/cardiac types require specific factors to promote myocardial regeneration after occurred injuries. Herein, cardiac stem cells (CSCs) as the major cell population that involved in cardiovascular repair were selected to study the role of polyethyleneimine (PEI) agent on endothelial differentiation. After preparation of electrospun network of PEI with polyacrylonitrile, the related characterizations were carried out including scanning electron microscope (SEM), field-emission SEM, water contact angle, Fourier transform infrared spectroscopy and mechanical properties. Also, the release kinetic of the corresponding agent was studied up to 7 days. The cell differentiation studies were done in the following with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, Real-time polymerase chain reaction and immunostaining method. The whole obtained results approved the higher differentiation of CSCs into endothelial/cardiac cells. Finally, it is recommended that the PEI delivering increases the healing potency of CSCs and accordingly the regeneration speed of damaged cardiovascular tissue would be improved.

Decellularized Wharton's jelly extracellular matrix as a promising scaffold for promoting hepatic differentiation of human induced pluripotent stem cells.

Liver tissue engineering as a therapeutic option for restoring of damaged liver function has a special focus on using native decellularized liver matrix, but there are limitations such as the shortage of liver donor. Therefore, an appropriate alternative scaffold is needed to circumvent the donor shortage. This study was designed to evaluate hepatic differentiation of human induced pluripotent stem cells (hiPSCs) in decellularized Wharton's jelly (WJ) matrix as an alternative for native liver matrix. WJ matrices were treated with a series of detergents for decellularization. Then hiPSCs were seeded into decellularized WJ scaffold (DWJS) for hepatic differentiation by a defined induction protocol. The DNA quantitative assay and histological evaluation showed that cellular and nuclear materials were efficiently removed and the composition of extracellular matrix was maintained. In DWJS, hiPSCs-derived hepatocyte-like cells (hiPSCs-Heps) efficiently entered into the differentiation phase (G1) and gradually took a polygonal shape, a typical shape of hepatocytes. The expression of hepatic-associated genes (albumin, TAT, Cytokeratin19, and Cyp7A1), albumin and urea secretion in hiPSCs-Heps cultured into DWJS was significantly higher than those cultured in the culture plates (2D). Altogether, our results suggest that DWJS could provide a proper microenvironment that efficiently promotes hepatic differentiation of hiPSCs.