Reconstructing Critical-Sized Mandibular Defects in a Rabbit Model: Enhancing Angiogenesis and Facilitating Bone Regeneration via a Cell-Loaded 3D-Printed Hydrogel-Ceramic Scaffold Application

In this study, we propose a spatially patterned 3D-printed nanohydroxyapatite (nHA)/beta-tricalcium phosphate (β-TCP)/collagen composite scaffold incorporating human dental pulp-derived mesenchymal stem cells (hDP-MSCs) for bone regeneration in critical-sized defects. We investigated angiogenesis and osteogenesis in a rabbit critical-sized mandibular defect model treated with this engineered construct. The critical and synergistic role of collagen coating and incorporation of stem cells in the regeneration process was confirmed by including a cell-free uncoated 3D-printed nHA/β-TCP scaffold, a stem cell-loaded 3D-printed nHA/β-TCP scaffold, and a cell-free collagen-coated 3D-printed nHA/β-TCP scaffold in the experimental design, in addition to an empty defect. Posteuthanasia evaluations through X-ray analysis, histological assessments, immunohistochemistry staining, histomorphometry, and reverse transcription-polymerase chain reaction (RT-PCR) suggest the formation of substantial woven and lamellar bone in the cell-loaded collagen-coated 3D-printed nHA/β-TCP scaffolds. Histomorphometric analysis demonstrated a significant increase in osteoblasts, osteocytes, osteoclasts, bone area, and vascularization compared to that observed in the control group. Conversely, a significant decrease in fibroblasts/fibrocytes and connective tissue was observed in this group compared to that in the control group. RT-PCR indicated a significant upregulation in the expression of osteogenesis-related genes, including BMP2, ALPL, SOX9, Runx2, and SPP1. The findings suggest that the hDP-MSC-loaded 3D-printed nHA/β-TCP/collagen composite scaffold is promising for bone regeneration in critical-sized defects.

The impact of high nicotine concentrations on the viability and cardiac differentiation of mesenchymal stromal cells: a barrier to regenerative therapy for smokers

Background: Current treatment methods are not successful in restoring the lost cardiomyocytes after injury. Stem cell-based strategies have attracted much attention in this regard. Smoking, as a strong cardiovascular risk factor, not only affects the cardiac cells adversely but also deteriorates the function of stem cells. Since mesenchymal stem cells (MSCs) are one of the popular candidates in cardiovascular disease (CVD) clinical trials, we investigated the impact of nicotine on the regenerative properties (viability and cardiac differentiation) of these cells. Methods: MSCs were isolated from rat bone marrow and characterized based on morphology, differentiation capability, and the expression of specific mesenchymal markers. The MTT assay was used to assess the viability of MSCs after being exposed to different concentrations of nicotine. Based on MTT findings and according to the concentration of nicotine in smokers' blood, the growth curve and population doubling time were investigated for eight consecutive days. Cells were treated with 5-azacytidine (an inducer of cardiac differentiation), and then the expressions of cardiac-specific markers were calculated by qPCR. Results: MSCs were spindle-shaped, capable of differentiating into adipocyte and osteocyte, and expressed CD73 and CD90. The viability of MSCs was reduced upon exposure to nicotine in a concentration- and time-dependent manner. The growth curve showed that nicotine reduced the proliferation of MSCs, and treated cells needed more time to double. In addition, the expressions of GATA4 and troponin were downregulated in nicotine-treated cells on day 3. However, these two cardiac markers were overexpressed on day 7. Conclusion: Nicotine decreased normal growth and reduced the expression of cardiac markers in MSCs. This aspect is of eminent importance to smokers with cardiovascular disease who are candidates for stem cell therapy.

Bone repair potential of collagen-poly(3-hydroxybutyrate)-carbon nanotubes scaffold loaded with mesenchymal stem cells for the reconstruction of critical-sized mandibular defects

The poor structural stability of collagen (COL) upon hydration poses a significant challenge in tissue engineering (TE). To overcome this limitation, the incorporation of hydrophobic polymers such as poly(3-hydroxybutyrate) (PHB), and nanomaterials such as carbon nanotubes (CNTs) has been explored. In this study, we investigated the physical, chemical, and biological characteristics of COL-based scaffolds modified with PHB and CNTs for bone tissue engineering (BTE) applications. The tensile strength analysis revealed a substantial improvement in the ultimate tensile strength with the addition of 10 % PHB and 4 % CNTs. Scanning electron microscopy (SEM) images depicted a denser and more compact structure resulting from the presence of PHB and CNTs, enhancing the scaffold's mechanical properties. Fourier-transform infrared spectroscopy (FTIR) confirmed the successful incorporation of PHB and CNTs into the composite scaffold, maintaining the chemical integrity of COL. Stereological studies also conducted in a rat model with induced critical-sized bone defects in the mandibular bone further emphasize the substantial increase in bone formation and reduction in defect volume achieved by the scaffold loaded with stem cells. These findings underscore the promising approach to enhance bone healing, using COL-based scaffolds loaded with stem cells, and the favorable results obtained in this study can contribute to the advancement of BTE strategies.

The impact of diabetic glucose concentration on viability and cardiac differentiation of mesenchymal stem cells

INTRODUCTION

Hyperglycemia may be a stumbling block for delivery of regenerative benefits of mesenchymal stem cells (MSCs) to diabetic patients with cardiovascular diseases. Our study aims to assess the viability and cardiac differentiation potential of MSCs after being exposed to diabetic glucose concentration.

METHODS

MSCs were extracted from rat bone marrow. Cells were characterized based on morphology, differentiation potential, and expression of mesenchymal specific markers. MTT assay was done to evaluate the viability of MSCs after treatment with different glucose concentrations. Case group was MSCs treated with diabetic concentration of glucose versus cells treated with PBS as the control group. Growth curve and population doubling time were calculated in both groups. Expression of GATA4 and troponin, as the early and late markers during cardiac differentiation, were measured following 5-azacytidine exposure.

RESULTS

Proliferated cells at passage three had fibroblastic-shape, was able to differentiate into adipocytes or osteocytes, and expressed CD73 and CD90. MSCs viability was gradually decreased by increasing glucose concentration. Irrespective of nicotine concentration, three-day exposure imposed more severe detrimental effects on viability compared with one-day treatment. Proliferation rate of the MSCs was lower in the case group, and they need more time for population doubling. Expression of both cardiac markers were downregulated in the case group at day three. However, their expression became higher at day seven.

CONCLUSION

Diabetic glucose concentration inhibits normal proliferation and cardiac differentiation of MSCs. This effect should be considered in stem cell therapy of cardiovascular patients who are concurrently affected by hyperglycemia, a common comorbidity in such individuals. Why carry out this study? What was learned from the study?

FINDINGS

The effects of combined and independent low-level laser and mesenchymal stem cell therapy on induced knee osteoarthritis: An animal study

BACKGROUND

Mesenchymal stem cell (MSC) injection has emerged as a novel treatment for knee osteoarthritis (OA). In addition, low-level laser therapy (LLLT) has been reported to delay the progression of OA. Thus, the current study on animal models of OA investigated the effectiveness of these methods when administered independently and combined.

METHODS

Twenty-five guinea pig models of OA were randomly sorted into five study groups. The test groups received intra-articular MSC, LLLT, and a combination of these therapeutics for 8 weeks. Radiological and histopathologic evaluations were carried out for the test groups and the control after the completion of treatments.

RESULTS

The MSC-treated groups showed better outcomes in terms of all radiological and histological indexes compared with the control, apart from subchondral bone (P < 0.05). Similarly, but to a different extent, the LLLT-treated group showed better results than the controls (P < 0.05). The combination of MSC therapy and LLLT improved the cartilage, surface, matrix, space width, osteophytes, and radiologic OA scores more effectively than each of these methods alone (P < 0.05).

CONCLUSIONS

According to our results, the combination of intra-articular MSC and LLLT can effectively improve OA in animal models. Further preclinical and clinical studies are recommended to assess the effectiveness of these therapeutics alone and in combination.

Phenyl-quinoline derivatives as lead structure of cholinesterase inhibitors with potency to reduce the GSK-3β level targeting Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder that leads to cognitive decline and memory loss. Unfortunately, there is no effective treatment for this condition, so there is a growing interest in developing new anti-AD agents. In this research project, a series of phenyl-quinoline derivatives were designed as potential anti-AD agents. These derivatives were substituted at two different positions on benzyl and phenyl rings. The structures of the derivatives were characterized using techniques such as IR spectroscopy, 1H NMR, 13C NMR, and elemental analysis. During the in vitro screening, the derivatives were tested against both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). It was observed that most of the derivatives showed higher selectivity against BChE compared to AChE. Among the derivatives, analog 7n (with a methoxy group at R1 and a 4-bromine substituent at R2 exhibited the highest potency, with a 75-fold improvement in the activity compared to the positive control. Importantly, this potent analog demonstrated no toxicity at the tested concentration on SH-SY5Y cells, indicating its potential as a safe anti-AD agent. The level of GSK-3β was also reduced after treatments with 7n at 50 μM. Overall, this study highlights the design and evaluation of phenyl-quinoline derivatives as promising candidates for developing novel anti-AD agents.

Comparison effect of collagen/P3HB composite scaffold and human amniotic membrane loaded with mesenchymal stem cells on colon anastomosis healing in male rats

Covering surgical wounds with biomaterials, biologic scaffolds, and mesenchymal stem cells (MSCs) improves the healing process and reduces postoperative complications. This study was designed to evaluate and compare the effect of MSC-free/MSC-seeded new collagen/poly(3-hydroxybutyrate) (COL/P3HB) composite scaffold and human amniotic membrane (HAM) on the colon anastomosis healing process. COL/P3HB scaffold was prepared using freeze-drying method. MSCs were isolated and characterized from rat adipose tissue. After biocompatibility evaluation by MTT assay, MSCs were seeded on the scaffold and HAM by micro-mass seeding technique. In total, 35 male rats were randomly divided into five groups. After the surgical procedure, cecum incisions were covered by the MSC-free/MSC-seeded scaffold or HAM. Incisions in the control group were only sutured. One month later, the healing process was determined by stereological analysis. The Kruskal-Wallis followed by Dunn's tests were utilized for statistical outcome analysis (SPSS software version 21). COL/10% P3HB scaffold showed the best mechanical and structural properties (7.86 MPa strength, porosity more than 75%). MTT assay indicated that scaffold and especially HAM have suitable biocompatibility. Collagenization and neovascularization were significantly higher, and necrosis was considerably lower in all treated groups in comparison with the controls. MSC-seeded scaffold and HAM significantly decrease inflammation and increase gland volume compared with other groups. The MSC-seeded HAM was significantly successful in decreasing edema compared with other groups. Newly synthesized COL/P3HB scaffold improves the colon anastomosis healing; however, the major positive effect belonged to HAM. MSCs remarkably increase their healing process. Further investigations may contribute to confirming these results in other wound healing.

Short-term beneficial effects of human dental pulp stem cells and their secretome in a rat model of mild ischemic stroke

Although cell therapy has been applied in regenerative medicine for decades, recent years have seen greatly increased attention being given to the use of stem cell-based derivatives such as cell-free secretome. Dental pulp stem cells (DPSCs) are widely available, easily accessible, and have high neuroprotective and angiogenic properties. In addition, DPSC-derived secretome contains a rich mixture of trophic factors. The current investigation evaluated the short-term therapeutic effects of human DPSCs and their secretome in a rat model of mild ischemic stroke. Mild ischemic stroke was induced by 30 min middle cerebral artery occlusion, and hDPSCs or their secretome was administered intra-arterially and intranasally. Neurological function, infarct size, spatial working memory, and relative expression of seven target genes in two categories of neurotrophic and angiogenic factors were assessed three days after stroke. In the short-term, all treatments reduced the severity of neurological and histological deficits caused by ischemic stroke. Moreover, transient middle cerebral artery occlusion led to the striatal and cortical over-expression of BDNF, NT-3, and angiogenin, while NGF and VEGF expression was reduced. Almost all interventions were able to modulate the expression of target genes after stroke. The obtained data revealed that single intra-arterial administration of hDPSCs or their secretome, single intranasal transplantation of hDPSCs, or repeated intranasal administration of hDPSC-derived secretome was able to ameliorate the devastating effects of a mild stroke, at least in the short-term.

The anti-Alzheimer potential of novel spiroindolin-1,2-diazepine derivatives as targeted cholinesterase inhibitors with modified substituents

In this study, a new series of spiro indolin-1,2-diazepine were designed, synthesized, and screened for their cholinesterase inhibitory activities. A novel, green, high-yielding approach was constructed to synthesize spiro indolin-1,2-diazepine derivatives through a cascade reaction of different isatins, malononitrile and 1,1-enediamines (EDAMs) via sequential four-component reactions to produce the target compounds with good to excellent yields. Next the inhibitory potencies of all derivatives were determined spectroscopically at 415 nm using the modified Ellman method. The results of the in vitro screening indicated that 5l with spiroindolin-1,2-diazepine core bearing 5-NO₂ at R¹ and 4-OH at R² was the most potent and selective AChE inhibitor with an IC₅₀ value of 3.98 ± 1.07 µM with no significant inhibition against BChE while 5j was the most active analog against both AChE and BChE enzymes. The structure-activity relationships suggested the variation in the inhibitory activities of derivatives was affected by different substitutions on the indolinone ring as well as the phenyl moiety. The enzyme kinetic studies of the most potent compound 5l at five different concentrations and acetylthiocholine substrate (0.1-1 mM) by Ellman's method revealed that it inhibited AChE in a mixed mode with a K_i of 0.044 μM. A molecular docking study was performed via induced fit docking protocol to predict the putative binding interaction. It was shown that the moieties used in the initial structure design play a fundamental role in interacting with the enzyme's binding site. Further, molecular dynamics simulations with the Schrödinger package were performed for 5l in a complex with AChE and revealed that compound 5l formed the stable complex with the enzyme. The MTT toxicity assessments against the neuroblastoma cell line were executed, and no toxicity was seen for 5l under the tested concentrations.

Proliferative Effect of Aqueous Extract of Sea Cucumber (Holothuria parva) Body Wall on Human Umbilical Cord Mesenchymal Stromal/Stem Cells

Sea cucumber extracts and their bioactive compounds have the potential for stem cell proliferation induction and for their beneficial therapeutic properties. In this study, human umbilical cord mesenchymal stromal/stem cells (hUC-MSCs) were exposed to an aqueous extract of Holothuria parva body walls. Proliferative molecules were detected using gas chromatography-mass spectrometry (GC-MS) analysis in an aqueous extract of H. parva. The aqueous extract concentrations of 5, 10, 20, 40, and 80 µg/mL and 10 and 20 ng/mL of human epidermal growth factor (EGF) as positive controls were treated on hUC-MSCs. MTT, cell count, viability, and cell cycle assays were performed. Using Western blot analysis, the effects of extracts of H. parva and EGF on cell proliferation markers were detected. Computational modeling was done to detect effective proliferative compounds in the aqueous extract of H. parva. A MTT assay showed that the 10, 20, and 40 µg/mL aqueous extract of H. parva had a proliferative effect on hUC-MSCs. The cell count, which was treated with a 20 µg/mL concentration, increased faster and higher than the control group (p < 0.05). This concentration of the extract did not have a significant effect on hUC-MSCs' viability. The cell cycle assay of hUC-MSCs showed that the percentage of cells in the G2 stage of the extract was biologically higher than the control group. Expression of cyclin D1, cyclin D3, cyclin E, HIF-1α, and TERT was increased compared with the control group. Moreover, expression of p21 and PCNA decreased after treating hUC-MSCs with the extract. However, CDC-2/cdk-1 and ERK1/2 had almost the same expression as the control group. The expression of CDK-4 and CDK-6 decreased after treatment. Between the detected compounds, 1-methyl-4-(1-methyl phenyl)-benzene showed better affinity to CDK-4 and p21 than tetradecanoic acid. The H. parva aqueous extract showed proliferative potential on hUC-MSCs.

Cell Proliferation, Viability, Differentiation, and Apoptosis of Iron Oxide Labeled Stem Cells Transfected with Lipofectamine Assessed by MRI

To assess in vitro and in vivo tracking of iron oxide labeled stem cells transfected by lipofectamine using magnetic resonance imaging (MRI), rat dental pulp stem cells (DPSCs) were characterized, labeled with iron oxide nanoparticles, and then transfected with lipofectamine to facilitate the internalization of these nanoparticles. Cell proliferation, viability, differentiation, and apoptosis were investigated. Prussian blue staining and MRI were used to trace transfected labeled cells. DPSCs were a morphologically spindle shape, adherent to culture plates, and positive for adipogenic and osteogenic inductions. They expressed CD73 and CD90 markers and lacked CD34 and CD45. Iron oxide labeling and transfection with lipofectamine in DPSCs had no toxic impact on viability, proliferation, and differentiation, and did not induce any apoptosis. In vitro and in vivo internalization of iron oxide nanoparticles within DPSCs were confirmed by Prussian blue staining and MRI tracking. Prussian blue staining and MRI tracking in the absence of any toxic effects on cell viability, proliferation, differentiation, and apoptosis were safe and accurate to track DPSCs labeled with iron oxide and transfected with lipofectamine. MRI can be a useful imaging modality when treatment outcome is targeted.

Comparing the healing properties of intra-articular injection of human dental pulp stem cells and cell-free-secretome on induced knee osteoarthritis in male rats

OBJECTIVE

Osteoarthritis (OA) is a common and painful joint disease with multifactorial causes. Stem cells, due to their high ability to reproduce and differentiate, have created a new horizon in tissue engineering of cartilage and bone. Secretions are one of the new therapies that can be used with stem cells or separately. This study aimed to compare the healing effects of human dental pulp stem cells, cell-free secretome, and human dental pulp mesenchymal stem cells with secretome in the induced OA in male rats.

METHODS

Dental pulp mesenchymal stem cells were isolated and prepared from human dental pulp. The collagenase type II was injected into the knee of twenty-five male Sprague-Dawley rats, and after 10 weeks, OA was confirmed. Rats were divided into five groups (n = 5): 1) Human dental pulp stem cells plus secretome (HDP+Sec); 2) Human dental pulp stem cells (HDP); 3) Secretome (Sec); 4) Hyalgan as the positive control (Hya); 5) No treatment as the negative control (Ctrl). After 12 weeks since OA was confirmed, the healing process was examined by histopathology and radiology evaluations.

RESULTS

Histopathological evaluations, radiological assessments, and matrix indexes in three treatment groups significantly improved compared to the Ctrl and Hya groups. Surface in HDP+Sec was significantly better than the Ctrl group. In radiological evaluations, a significant decrease in OA was observed in the three treatment groups in comparison with the Ctrl groups. There was no significant difference between the treatment groups in any radiological and histopathological evaluations. HDP + Sec group slightly records better results compared to Sec or HDP treatment groups.

CONCLUSION

It was concluded that human dental pulp stem cells and their secretome promote cartilage regeneration due to their cell protective potential as well as matrix degeneration reduction capacity.

in Vitro Effect of Methamphetamine on Proliferation, Differentiation and Apoptosis of Adipose Tissue Stem Cells

PURPOSE

Among abused substances, methamphetamine is a psychostimulant drug widely used recreationally with public health importance. This study investigated the effect of methamphetamine on proliferation, differentiation, and apoptosis of human adipose tissue stem cells (AdSCs).

METHODS

AdSCs were isolated from human abdominal adipose tissue and were characterized for mesenchymal properties and growth kinetics. MTT assay was undertaken to assess methamphetamine toxicity on proliferation and differentiation properties and apoptosis of hAdSCs.

RESULTS

Isolated cells were shown to have mesenchymal properties and a population doubling time (PDT) of 40.1 h. Following methamphetamine treatment, expressions of KI-67 and TPX2 as proliferation genes and Col1A1 and PPARg as differentiation genes decreased. Methamphetamine administration increased the expression of Bax and decreased Bcl-2 genes responsible for apoptosis.

CONCLUSIONS

Our data suggested when AdSCs were exposed to methamphetamine, it decreased proliferation and differentiation properties of stem cells together with an increase in apoptosis. These findings can be added to the literature, especially when methamphetamine is used recreationally for weight loss purposes.

Attenuation of osteoarthritis progression through intra-articular injection of a combination of synovial membrane-derived MSCs (SMMSCs), platelet-rich plasma (PRP) and conditioned medium (secretome)

PURPOSE

Osteoarthritis (OA) as a progressive destructive disease of articular cartilage is the most common joint disease characterized by reduction of joint cartilage thickness, demolition of cartilage surface and new bone formation. To overcome these problems, the purpose of the current research was to evaluate and compare the in vivo effects of synovial membrane-derived mesenchymal stem cell (SMMSCs), platelet-rich plasma (PRP) and conditioned medium (secretome) on collagenase II-induced rat knee osteoarthritis (KOA) remedy.

METHODS

For the first step, SMMSCs were isolated and characterized. Also, secretome was collected from SMMSCs culture. Furthermore, PRP was collect from the rat heart venous blood. Second, two injection of collagenase II with an interval of 3 days was performed in the knee intra-articular space to induce osteoarthritis. Two weeks later, animals were randomly divided into 6 groups. Control group without treatment, positive group: taken an intra-articular sodium hyaluronate injection (0.1 ml), treatment groups taken an intra-articular injection of; treatment 1: SMMSCs (5 × 10⁶), treatment 2: SMMSCs (5 × 10⁶)/secretome (50 µl), treatment 3: SMMSCs (5 × 10⁶)/PRP (50 µl), and treatment 4: SMMSCs (5 × 10⁶)/ secretome (50 µl)/ PRP (50 µl). Three months later, rats were killed and the following assessments were executed: radiography, histopathology, and immunohistochemistry.

RESULTS

Our findings represented that a combination of the SMMSCs/secretome/PRP had a considerable effect on glycosaminoglycans (GAGs) and collagen II contents, articular cartilage preservation, compared with other groups. In addition, combination of the SMMSCs with PRP and secretome showed the lowest expression of mmp3, while SOX9 had the highest expression in comparison with other groups. Also, SMMSCs-injected groups demonstrated better results compared with positive and control groups.

CONCLUSIONS

Injecting a combination of the SMMSCs/secretome/PRP resulted in better efficacy in terms of joint space width, articular cartilage surface continuity and integrity, sub-chondral bone and ECM constituents such as collagen II. Indeed, transplantation of this combination could be considered as a preliminary therapy for clinical trial study in the future.

Preconditioning with secretome of neural crest-derived stem cells enhanced neurotrophic expression in mesenchymal stem cells

During the last 20 years, stem cell therapy has been considered as an effective approach for regenerative medicine. Due to poor ability of stem cells to survive following transplantation, it has been proposed that beneficial effects of stem cells mainly depend on paracrine function. Therefore, the present study was designed to reinforce mesenchymal stem cells (MSCs) to express higher levels of trophic factors especially the ones with the neurotrophic properties. Here, bone marrow (BM)-MSCs and adipose-MSCs were treated with conditioned medium (CM) of dental pulp stem cells (DPSCs) or hair follicle stem cells (HFSCs) for up to three days. The relative expression of five key trophic factors that have critical effects on the central nervous system regeneration were evaluated using qRT-PCR technique. Furthermore, to assess the impacts of conditioned mediums on the fate of MSCs, expression of seven neuronal/glial markers were evaluated 3 days after the treatments. The obtained data revealed priming of BM-MSCs with HFSC-CM or DPSC-CM increases the BDNF expression over time. Such effect was also observed in adipose-MSCs following DPSC-CM treatment. Secretome preconditioning remarkably increased NGF expression in the adipose-MSCs. In addition, although priming of adipose-MSCs with HFSC-CM increased GDNF expression one day after the treatment, DPSC-CM enhanced GDNF mRNA in BM-MSCs at a later time point. It seemed priming of BM-MSCs with HFSC-CM, promoted differentiation into the glial lineage. Our findings showed that MSCs preconditioning with secretome of neural crest-derived stem cells could be a promising approach to enhance the neurotrophic potential of these stem cells.

OUP accepted manuscript

Background

In vivo cell tracking after transplantation in regenerative medicine remains an unmet challenge and limits current understanding of the wound healing mechanism through cell-based therapies. This study investigated tracking of human Wharton’s jelly stem cells (hWJSCs) seeded onto an acellular dermal matrix (ADM) and labeled with superparamagnetic iron oxide nanoparticles (SPIONs) by magnetic resonance imaging (MRI) in burn injury.

Method

The hWJSCs were characterized and assessed for growth kinetics. A total of 30 rats were enrolled in three equal groups. Group 1 underwent scald burn injury left without treatment, the group 2 was treated by an ADM that was prepared from cosmetic surgery skin samples and the group 3 received hWJSCs labeled with SPIONs seeded onto an ADM. Tensile strength was evaluated before and after interventions, real time PCR assessed apoptosis, and Prussian blue staining, scanning electron microscopy (SEM) and MRI were used for the tracking of labeled cells.

Results

The hWJSCs exhibited mesenchymal stem cell properties. Population doubling time was 40.1 hours. SPIONs did not show any toxic effect. The hWJSCs seeded onto an ADM decreased Bax and increased Bcl-2 gene expression. Internalization of SPIONs within hWJSCs was confirmed by Prussian blue staining, SEM and MRI until day 21. There was a significant difference between the Young’s moduli of normal skin and the group receiving hWJSCs seeded onto an ADM. Histological observations and SEM imaging confirmed that MRI is an accurate method to track SPION-labeled hWJSCs in vivo.

Conclusions

This study showed that SPION labeling coupled with MRI can be used to further understand the fate of stem cells after transplantation in a burn model.

Spinal cord injury repair using mesenchymal stem cells derived from bone marrow in mice: A stereological study

Transplantation of bone marrow stem cells (BMSCs) has shown to have a vital role in promoting nerve regeneration after SCI. The aim of this study was to investigate the effect of BMSCs transplantation in healing of spinal cord injury (SCI) in mice based on morphologic parameters. Forty two male mice were randomly divided into 3 groups of control with no intervention, experimental SCI without treatment, and experimental SCI transplanted with 2 × 10⁵ BMSCs intravenously. To induce SCI bilaterally, T10 was compressed for 2 min. The animals were sacrificed 3 and 5 weeks after SCI and T7-T11 segments of spinal cord were removed and stained by Giemsa and H&E methods. Stereological assessment estimated the gray and white matter volume, the number of neurons and neuroglia and diameter of central canal. The average amount of gray matter in SCI injury group was significantly lower than control group. An increase in the number of neurons was noted after cell transplantation. The number of neurons in SCI injury group significantly decreased in comparison to the control group. In cell transplantation group, a significant increase in the number of neurons was visible when compared to SCI injury group. The increase in the number of neurons after cell transplantation denotes to the regenerative potential of BMSCs in SCI. These findings can be added to the literature and open a new window when targeting treatment of SCI.

Comparing the effects of Elaegnus Angustifolia, Hypericum Perforatum and Psidium Guajava extracts on metabolic activity of dental pulp-derived mesenchymal stem cells

Dental pulp derived-mesenchymal stem cells (DP-MSCs) is considered a suitable are candidate for tissue engineering techniques and osseous reconstruction. Based on the hypothesis that Hypericum perforatum, Elaeagnus Angustifolia and Psidium guajava extracts can be used in cell-based bone tissue engineering due to meagre cytotoxicity response in the cell culture medium, their effects on the viability and metabolic activity of DP-MSCs were investigated and compared with each extract. DP-MSCs were extracted from human dental pulp, characterized by flow cytometry, and differentiated into Osteogenic and adipogenic lineages which were then cultured in different concentrations of E. Angustifolia, H. perforatum and P. guajava extracts at different time intervals followed by MTT assay evaluation. The dental pulp mesenchymal stem cells were evaluated for their plastic adherence ability, fibroblast-like and spindle morphology. According to flow cytometry data, isolated cells from DP-MSCs expressed MSCs markers. A comparison of herbal extracts' concentrations revealed that 500 μg/ml was toxic to dental pulp stem cells, a guide to the toxic dose for DP-MSCs. The P.guajava bore low toxicity and increased dental pulp stem cell viability in comparison to the other two herbal extracts. The hydro-alcoholic extracts of E. Angustifolia, H. perforatum, and P. guajava were efficient in DP-MSCs viability, and therefore were concluded to be useful in maintaining structural and functional cell viability. It was also concluded that the co-culture of stem cells with herbal elements could stimulate endogenous factors to enhance the proliferation and viability of MSCs.

Poly(3-Hydroxybutyrate)-Multiwalled Carbon Nanotubes Electrospun Scaffolds Modified with Curcumin

Appropriate selection of suitable materials and methods is essential for scaffolds fabrication in tissue engineering. The major challenge is to mimic the structure and functions of the extracellular matrix (ECM) of the native tissues. In this study, an optimized 3D structure containing poly(3-hydroxybutyrate) (P3HB), multiwalled carbon nanotubes (MCNTs) and curcumin (CUR) was created by electrospinning a novel biomimetic scaffold. CUR, a natural anti-inflammatory compound, has been selected as a bioactive component to increase the biocompatibility and reduce the potential inflammatory reaction of electrospun scaffolds. The presence of CUR in electrospun scaffolds was confirmed by 1H NMR and Fourier-transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed highly interconnected porosity of the obtained 3D structures. Addition of up to 20 wt% CUR has enhanced mechanical properties of the scaffolds. CUR has also promoted in vitro bioactivity and hydrolytic degradation of the electrospun nanofibers. The developed P3HB-MCNT composite scaffolds containing 20 wt% of CUR revealed excellent in vitro cytocompatibility using mesenchymal stem cells and in vivo biocompatibility in rat animal model study. Importantly, the reduced inflammatory reaction in the rat model after 8 weeks of implantation has also been observed for scaffolds modified with CUR. Overall, newly developed P3HB-MCNTs-CUR electrospun scaffolds have demonstrated their high potential for tissue engineering applications.

Poly(3-Hydroxybutyrate)-Multiwalled Carbon Nanotubes Electrospun Scaffolds Modified with Curcumin

Appropriate selection of suitable materials and methods is essential for scaffolds fabrication in tissue engineering. The major challenge is to mimic the structure and functions of the extracellular matrix (ECM) of the native tissues. In this study, an optimized 3D structure containing poly(3-hydroxybutyrate) (P3HB), multiwalled carbon nanotubes (MCNTs) and curcumin (CUR) was created by electrospinning a novel biomimetic scaffold. CUR, a natural anti-inflammatory compound, has been selected as a bioactive component to increase the biocompatibility and reduce the potential inflammatory reaction of electrospun scaffolds. The presence of CUR in electrospun scaffolds was confirmed by 1H NMR and Fourier-transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed highly interconnected porosity of the obtained 3D structures. Addition of up to 20 wt% CUR has enhanced mechanical properties of the scaffolds. CUR has also promoted in vitro bioactivity and hydrolytic degradation of the electrospun nanofibers. The developed P3HB-MCNT composite scaffolds containing 20 wt% of CUR revealed excellent in vitro cytocompatibility using mesenchymal stem cells and in vivo biocompatibility in rat animal model study. Importantly, the reduced inflammatory reaction in the rat model after 8 weeks of implantation has also been observed for scaffolds modified with CUR. Overall, newly developed P3HB-MCNTs-CUR electrospun scaffolds have demonstrated their high potential for tissue engineering applications.

Poly(3-Hydroxybutyrate)-Multiwalled Carbon Nanotubes Electrospun Scaffolds Modified with Curcumin

Appropriate selection of suitable materials and methods is essential for scaffolds fabrication in tissue engineering. The major challenge is to mimic the structure and functions of the extracellular matrix (ECM) of the native tissues. In this study, an optimized 3D structure containing poly(3-hydroxybutyrate) (P3HB), multiwalled carbon nanotubes (MCNTs) and curcumin (CUR) was created by electrospinning a novel biomimetic scaffold. CUR, a natural anti-inflammatory compound, has been selected as a bioactive component to increase the biocompatibility and reduce the potential inflammatory reaction of electrospun scaffolds. The presence of CUR in electrospun scaffolds was confirmed by 1H NMR and Fourier-transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed highly interconnected porosity of the obtained 3D structures. Addition of up to 20 wt% CUR has enhanced mechanical properties of the scaffolds. CUR has also promoted in vitro bioactivity and hydrolytic degradation of the electrospun nanofibers. The developed P3HB-MCNT composite scaffolds containing 20 wt% of CUR revealed excellent in vitro cytocompatibility using mesenchymal stem cells and in vivo biocompatibility in rat animal model study. Importantly, the reduced inflammatory reaction in the rat model after 8 weeks of implantation has also been observed for scaffolds modified with CUR. Overall, newly developed P3HB-MCNTs-CUR electrospun scaffolds have demonstrated their high potential for tissue engineering applications.

In utero xenotransplantation of mice bone marrow-derived stromal/stem cells into fetal rat liver: An experimental study

Background

Animals can play an important role in preparing tissues for human through the development of xenotransplantation protocols. The most common problem with liver transplantation like any other organ transplantation is organ supply shortage.

Objective

To evaluate the in utero xenotransplantation of mouse bone marrow-derived stromal/stem cells (BMSCs) to the liver of rat fetus to produce mouse liver tissue.

Materials and Methods

BMSCs were isolated and confirmed from enhanced green fluorescent protein (eGFP)-genetic labeled mice. Using a microinjection protocol, mice BMSCs were injected into the liver of rat fetuses in utero on day 14 of pregnancy. After birth, livers were collected and the presence of mice eGFP-positive cells in rat livers was evaluated through polymerase chain reaction.

Results

The eGFP mRNA was detected in the liver of injected infant rats. BMSCs of adult mice were capable to remain functional probably as hepatocyte-like cells in liver of infant rats after in utero xenotransplantation.

Conclusion

BMSCs have the potential for intrauterine xenotransplantation for the treatment of liver dysfunction before birth. This method can also be used for xenoproduction of liver tissue for transplantation.

Melatonin attenuates chemical-induced cardiotoxicity

Environmental chemicals and drugs can induce cardiotoxicity, mainly by generating free radicals. Reactive oxygen species play a critical role in the pathogenesis of cardiac tissue injury. This highlights a need for prevention of cardiotoxicity by scavenging free radicals. Melatonin has been shown to act as a protector against various conditions in which free radicals cause molecular and tissue injury. Some of the mechanisms by which melatonin operates as a free radical scavenger and antioxidant have been identified. The importance of endogenous melatonin in cardiovascular health and the benefits of melatonin supplementation in different cardiac pathophysiological disorders have been shown in a variety of model systems. Melatonin continues to attract attention for its potential therapeutic value for cardiovascular toxicity. The therapeutic potential of melatonin in treatment of cardiotoxicities caused by various chemicals along with suggested molecular mechanisms of action for melatonin is reviewed.

The Effect of Age and Type of Media on Growth Kinetics of Human Amniotic Fluid Stem Cells

Aim: This study compared growth kinetics of human amniotic fluid stem cells (hAFSCs) in different maternal age groups and two different media of AmnioMAX and Dulbecco's modified Eagle's medium (DMEM). Materials and Methods: Three milliliters of amniotic fluid (AF) was provided from 16 pregnant women who were referred for amniocentesis from 16 to 18 weeks of gestation. Mothers were divided to 20-29 (n = 5), 30-39 (n = 5) and 40-49 (n = 6) years old age groups. AF was immediately centrifuged and the cell pellet was cultured. Cells were characterized morphologically, by flow cytometry and for osteogenic and adipogenic inductions. Population doubling time (PDT) and growth kinetics were determined. AFSCs cultured in AmnioMAX were compared in various age groups. A comparison of growth kinetics of AFSCs cultured in AmnioMAX and DMEM from 40 to 49 years old pregnant women was undertaken. Results: AFSCs were adherent to culture flasks and were spindle shape, and positive for osteogenic and adipogenic inductions and for expression of CD73, CD90 and CD105 markers, but negative for CD34 and CD45. PDT among 20-29, 30-39, and 40-49 years old women was 30.9, 38.3, and 43.9 hours, respectively showing a higher cell proliferation in younger ages. When comparing AmnioMAX and DMEM, PDT was 53 and 96.9 hours, respectively denoting to a higher cell proliferation in AmnioMAX. Conclusions: Higher proliferation and plasticity of hAFSCs were noted in AmnioMAX and in younger mothers' samples. These findings can be added to the literature and open a new avenue in regenerative medicine, when hAFSCs are targeted for cell therapy purposes.

Epidermal neural crest stem cell transplantation as a promising therapeutic strategy for ischemic stroke

Introduction

Cell‐based therapy is considered as promising strategy to cure stroke. However, employing appropriate type of stem cell to fulfill many therapeutic needs of cerebral ischemia is still challenging. In this regard, the current study was designed to elucidate therapeutic potential of epidermal neural crest stem cells (EPI‐NCSCs) compared to bone marrow mesenchymal stem cells (BM‐MSCs) in rat model of ischemic stroke.

Methods

Ischemic stroke was induced by middle cerebral artery occlusion (MCAO) for 45 minutes. Immediately after reperfusion, EPI‐NCSCs or BM‐MSCs were transplanted via intra‐arterial or intravenous route. A test for neurological function was performed before ischemia and 1, 3, and 7 days after MCAO. Also, infarct volume ratio and relative expression of 15 selected target genes were evaluated 7 days after transplantation.

Results

EPI‐NCSCs transplantation (both intra‐arterial and intravenous) and BM‐MSCs transplantation (only intra‐arterial) tended to result in a better functional outcome, compared to the MCAO group; however, this difference was not statistically significant. The infarct volume ratio significantly decreased in NCSC‐intra‐arterial, NCSC‐intravenous and MSC‐intra‐arterial groups compared to the control. EPI‐NCSCs interventions led to higher expression levels of Bdnf, nestin, Sox10, doublecortin, β‐III tubulin, Gfap, and interleukin‐6, whereas neurotrophin‐3 and interleukin‐10 were decreased. On the other hand, BM‐MSCs therapy resulted in upregulation of Gdnf, β‐III tubulin, and Gfap and down‐regulation of neurotrophin‐3, interleukin‐1, and interleukin‐10.

Conclusion

These findings highlight the therapeutic effects of EPI‐NCSCs transplantation, probably through simultaneous induction of neuronal and glial formation, as well as Bdnf over‐expression in a rat model of ischemic stroke.

Evaluating and managing the probability of medical errors in nursing personnel using the HEART method

Introduction: Medical errors cause serious and often preventable injuries to patients. Studying human errors and their use as an opportunity for learning is a key factor in the effort to improve patient safety and quality of care in the hospitals. The purpose of this study was to identify and evaluate human errors to reduce their risks in nursing personnel using the Human Error Evaluation and Reduction (HEART) method.Materials and Methods: This cross-sectional descriptive study was performed in one of the hospitals of Rafsanjan in 1977. Initially, hierarchical task analysis was performed using HTA method and nurses' tasks were identified. In the next step, the probability of their human errors during work for all tasks was determined using the HEART method and the factors and conditions that were effective in causing the error were determined. Finally, in light of these conditions, suggestions were made to reduce the likelihood of these errors occurring.Results: The mean (standard deviation) human error score for the different tasks of nursing job was 1.79 (3.44). The maximum likelihood of error occurring in relation to the task of regulating and applying DC shock in emergencies was determined as 14.48. The least probability of error occurring for skin care task was 0.0014. The results of this study regarding the conditions that can lead to human error in nurses showed that the most important error generating conditions in nurses were novice and inexperienced, high stress, unreliable work tool, lack of control system transparency, lack of clarity and timely and direct confirmation of action. The highest mean human error probability score for Type C tasks was 4.34. Also the mean human error probability score for D, E and G tasks were 0.225, 0.198, and 0.00206 from right to left, respectively. The results of Kruskal-Wallis nonparametric test showed that there was a statistically significant difference among the mean scores of human error probability scores of different groups (P-value <0.001).Conclusion: Considering the critical consequences of human errors in nurses' work activities, developing specialized guidelines for their various activities, providing specialized training, as well as retraining of scientific and practical skills, increasing the workforce, reducing overtime, regular work shifts to improve the reliability of medical staff performance and familiarize staff with the risks that may result from errors in patients are necessary to reduce the likelihood of errors occurring in nurses.

In Vitro and In Vivo Evaluation of Poly (3-hydroxybutyrate)/Carbon Nanotubes Electrospun Scaffolds for Periodontal Ligament Tissue Engineering

STATEMENT OF THE PROBLEM

Tissue engineering was an idea, today it has become a potential therapy for several tissues in dentistry, such as periodontal disease and oral mucosa.

PURPOSE

In this experimental study, periodontal regeneration is one of the earliest clinical disciplines that has achieved therapeutic application in tissue engineering. The aim of the present study was to prepare electrospun Poly (3-hydroxybutyrate) (PHB)/1% Carbon nanotubes (CNTs) scaffolds for periodontal regeneration.

MATERIALS AND METHOD

1% w/v of CNTs was added to the polymer solutions and electrospinned. Physical properties of the scaffolds were evaluated by scanning electron microscopy (SEM) and universal testing machine. Chemical characterization of the scaffolds was also assessed by Fourier-transform infrared spectroscopy (FTIR). Biological properties of the scaffolds were also evaluated in vitro by culturing periodontal ligament stem cells (PDLSCs) on the scaffolds for 10 days and in vivo by Implanting the scaffolds in rat model for 5 weeks.

RESULTS

Results showed that the scaffolds mimicked fibrous connective tissue of the (PDL). CNTs improved the mechanical properties, similar to 23-55 years old human PDL. In vitro biocompatibility study showed more attachment and proliferation of the PDLSCs for PHB/1%CNTs scaffolds compared to the PHB controls. In vivo study showed that CNTs in the scaffolds caused mild foreign body type giant cell reaction, moderate vascularization, and mild inflammation.

CONCLUSION

The results showed that the PHB/1%CNTs composite scaffolds might be potentially useful in periodontal regeneration.

Lipophilic tracer Dil and fluorescence labeling of acridine orange used for Leishmania major tracing in the fibroblast cells

Background

This study aims to evaluate the use of fluorescent dye Dil and super vital dye acridine orange (AO) in vitro tracking of labeled L. major in the fibroblast cells.

Methods

Dil crystal and AO were used to stain L. major in a co-culture of the fibroblasts with the parasite. AO staining solution was added to 1 × 10⁶ parasites. After 10 min, the stained parasites were centrifuged and washed seven times with phosphate buffered saline (PBS). The stained promastigote was incubated with fibroblasts for 6-8 h. The presence of stained parasites with AO in the fibroblast was assessed using a fluorescence microscope. 1 × 10⁶/mL promastigote of L. major was gently suspended and mixed by Dil staining solution with an ultimate concentration of 0.002 μg/mL and it was kept for 20 min at the room temperature. Subsequently, after washing it in PBS for seven times, it was centrifuged at 3000 rpm for 10 min. The supernatant was removed and the precipitate containing stained promastigote was suspended in fresh DMEM F12 with fibroblasts at 37 °C for 6 h. The presence of stained parasites with Dil in fibroblast was assessed using a fluorescence microscope. Fibroblast characterization was undertaken by a real-time polymerase chain reaction (PCR).

Results

Acridine orange staining assisted in detection of the live parasite in the fibroblast cells. Free promastigote looked green before entering into the fibroblasts after 12 h culture. The parasite entered the cytoplasm of fibroblasts at the beginning of the exposure and gradually entered the nucleus of the fibroblast. The fibroblast nucleus was entirely stained green by AO. The L. major appeared green under the fluorescent microscope. Dil staining revealed that the internalized parasites with red/orange color were localized within the cytoplasm after 6-hours and the nucleus of the fibroblasts after 72-hours following culture. Human fibroblasts were positive at the expression of CD10, CD26, matrix metalloproteinase-1 (MMP-1) and matrix metalloproteinase-3 (MMP-3) and negative for CD106 and integrin alpha 11.

Conclusion

The fluorescent dye Dil staining is a safe, easy to use, inexpensive and fast method for labeling of the Leishmania parasite in the fibroblast cells. Acridine orange staining could be useful for tracing the parasites in the fibroblasts too. In this study, both Dil and AO were compared and considered as suitable vital dyes for identifying labeled Leishmania in the fibroblast in vitro, but Dil was superior to AO with its feature does not transfer from the labeled to unlabeled cells.

Regenerative Effect of Bone Marrow-derived Mesenchymal Stem Cells in Thioacetamide-induced Liver Fibrosis of Rats

The present study determined the regenerative effect of bone marrow-derived stem cells (BMSCs) on thioacetamide (TA)-induced liver fibrosis in rats. A total of 30 male Wistar rats were randomly divided into sham control and treatment groups. The rats of the sham control group were subdivided into three groups and sampled on the 14th, 18th, and 20th weeks after fibrosis induction. The rats of the treatment group were subdivided into two groups and sampled on the 4th and 6th weeks after BMSCs treatment. Fibrosis was induced by the intraperitoneal administration of 200 mg/kg of TA twice a week for a period of 14 weeks. All the animals underwent liver function tests and histopathologic evaluation 4 and 6 weeks after BMSCs transplantation. The BMSCs were characterized using osteogenic induction and reverse transcription-polymerase chain reaction. The BMSCs were plastic adherent, spindle-shaped, and positive for osteogenic differentiation. They expressed CD73 and were negative for CD45. The infiltration of inflammatory cells and deposition of collagen fibers were noticed after TA administration. A significant decline in inflammatory cells and a healing process were detected 4 weeks after cell transplantation. The amelioration in hepatic tissue was significant 6 weeks after cell therapy. Following the injection of BMSCs, a nonsignificant decrease was visible in aspartate transaminase level; however, this decline was significant for alanine aminotransferase level. The alkaline phosphatase and albumin levels showed an increasing trend after cell administration. The transplantation of BMSCs resulted in a significant regenerative effect after hepatic injuries. Therefore, it was shown that BMSCs transplantation can open a new window and be a therapy of choice in the amelioration of liver fibrosis.

The effect of allogenic human Wharton's jelly stem cells seeded onto acellular dermal matrix in healing of rat burn wounds

BACKGROUND

Various methods were introduced to overcome the autograft shortage in burn wound care, including cell transplantation and tissue engineering.

AIMS

To evaluate the healing effect of allogenic human Wharton's jelly stem cells (hWJSCs) seeded onto acellular dermal matrix (ADM) in rat burn injuries.

PATIENTS AND METHODS

Human Wharton's jelly stem cells provided from umbilical cord tissue were characterized before transplantation, and the growth kinetic was determined. Skin samples from cosmetic surgeries were used for preparation of ADM. Forty male Sprague Dawley rats were randomly divided into 4 equal groups. Third-degree burn was induced for all animals by exposing to hot water using a 2 cm ring for 10 seconds. Group 1 was burned rats that did not receive any treatment. After burn injury, the second group received silver sulfadiazine (SSD), the third group was treated just by using ADM, and the fourth group received 2 × 10⁶ hWJSCs seeded onto ADM. The animals were euthanized for histologic evaluation after 7, 14, and 21 days.

RESULTS

Human Wharton's jelly stem cells were characterized to be spindle shape and positive for osteogenic and adipogenic induction and for mesenchymal markers but lacked hematopoietic markers. Population doubling time (PDT) was 40.1 hours with an increasing growth trend until day 6th. Macro- and microscopically, the healing was mild in ADM group and moderate in ADM + hWJSCs group after 21 days.

CONCLUSION

Allogenic hWJSCs seeded onto ADM improved the healing process in burn wounds denoting to their therapeutic and anti-inflammatory effects in burn wounds that can be added to the literature.

Preparation and performance evaluation of electrospun poly(3-hydroxybutyrate) composite scaffolds as a potential hard tissue engineering application

In the present study, poly(3-hydroxybutyrate)-based composite scaffolds were prepared with multi-walled carbon nanotubes and hydroxyapatite nanoparticles for hard tissue engineering applications by electrospinning. All the prepared scaffolds showed connective porous structure, which were suitable for cell proliferation and migration. The mechanical properties of the poly(3-hydroxybutyrate) scaffold were improved by 0.5% of carbon nanotube addition, whereas the addition of hydroxyapatite nanoparticles up to 10% had an insignificant effect in tensile strength. However, scanning electron microscopy and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay results suggested that the mesenchymal stem cells attachment and their metabolic activities on the surface of the poly(3-hydroxybutyrate) scaffolds with hydroxyapatite were enhanced compared to poly(3-hydroxybutyrate) scaffolds. In addition, after 6 weeks of in vivo biocompatibility results in a model of rat indicated better tissue reactions for the scaffolds that contained hydroxyapatite. Overall, poly(3-hydroxybutyrate) composite scaffolds with 10% hydroxyapatite and 0.5% carbon nanotube showed optimal performances for the potential scaffold for hard tissue engineering application.

MRI-Tracking of Dental Pulp Stem Cells In Vitro and In Vivo Using Dextran-Coated Superparamagnetic Iron Oxide Nanoparticles

The aim of this study was to track dental pulp stem cells (DPSCs) labeled with dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs) using magnetic resonance imaging (MRI). Dental pulp was isolated from male Sprague Dawley rats and cultured in Dulbecco's modified Eagle's medium F12 (DMEM-F12) and 10% fetal bovine serum. Effects of SPIONs on morphology, viability, apoptosis, stemness, and osteogenic and adipogenic differentiation of DPSCs were assessed. Prussian blue staining and MRI were conducted to determine in vitro efficiency of SPIONs uptake by the cells. Both non-labeled and labeled DPSCs were adherent to culture plates and showed spindle-shape morphologies, respectively. They were positive for osteogenic and adipogenic induction and expression of cluster of differentiation (CD) 73 and CD90 biomarkers, but negative for expression of CD34 and CD45 biomarkers. The SPIONs were non-toxic and did not induce apoptosis in doses less than 25 mg/mL. Internalization of the SPIONs within the DPSCs was confirmed by Prussian blue staining and MRI. Our findings revealed that the MRI-based method could successfully monitor DPSCs labeled with dextran-coated SPIONs without any significant effect on osteogenic and adipogenic differentiation, viability, and stemness of DPSCs. We provided the in vitro evidence supporting the feasibility of an MRI-based method to monitor DPSCs labeled with SPIONs without any significant reduction in viability, proliferation, and differentiation properties of labeled cells, showing that internalization of SPIONs within DPSCs were not toxic at doses less than 25 mg/mL. In general, the SPION labeling does not seem to impair cell survival or differentiation. SPIONs are biocompatible, easily available, and cost effective, opening a new avenue in stem cell labeling in regenerative medicine.

Endometrial mesenchymal stem stromal cells in mature and immature sheep: An in vitro study

BACKGROUND

Endometrial mesenchymal stem stromal cells (EnMSCs) are critical for uterine function, repair, and regeneration.

OBJECTIVE

This study introduced isolation technique of EnMSCs and compared the characteristics of EnMSCs in mature and immature ewes.

MATERIALS AND METHODS

Endometrial tissue samples from the uterus of 10 ewes were collected from the slaughterhouse. Endometrial cells were isolated from tissue using cold incubation and then chopping and treating was performed with collagenase type I. Isolated cells were cultured in cell culture medium and then attached cells to flasks were harvested as EnMSCs and subcultured. To enumerate the cells, the population doubling time (PDT) was determined and 2.2×10⁴ cells in passage 4 were seeded into 24-well culture plates to compare the growth curves of isolated cells. Reverse transcription polymerase chain reaction (RT-PCR) was performed for detection of CD34 and CD73 markers. The osteogenic and adipogenic potential of isolated cells were determined using differentiation tests.

RESULTS

EnMSCs adhered to the flasks and displayed spindle-shape. Based on findings of the cell count and the growth curves, the EnMSCs growth was significantly more prominent in immature ewes in comparison to mature sheep. The PDT of EnMSCs in immature ewes was about 21 hr whereas this time period was two times higher (45 hr) in mature sheep. RT-PCR analyses of EnMSCs were positive for CD73 and negative for CD34. EnMSCs were differentiated into osteoblasts and adipocytes.

CONCLUSION

Based on mesenchymal stem cells characters confirmed in EnMSCs, they can be a candidate for cell therapy and regenerative medicine.

The Healing Effect of Conditioned Media and Bone Marrow-Derived Stem Cells in Laryngotracheal Stenosis: A Comparison in Experimental Dog Model

BACKGROUND

Differences in causes, severities, areas of stenosis, and the association with swallowing and phonation of larynx and trachea can result into Laryngotracheal stenosis (LTS).This study evaluated the healing effect of bone marrow stem cells (BMSCs) in experimentally induced LTS dog model.

METHODS

Seven dogs were enrolled. BMSCs were isolated from proximal humerus and shoulder of a dog and cultured in media containing alpha minimal essential medium, fetal bovine serum, penicillin and streptomycin, and L-glutamine. BMSCs were characterized morphologically, by RT-PCR, and osteogenic induction. Karyotyping was undertaken for chromosomal stability. Mechanical trauma to laryngeal mucosa was identically conducted by Tru-cut punch forceps in right and left vocal folds. Two milliliter of conditioned media or BMSCs (2×10⁶) were injected in the right site of the tissue and the left side was considered as control after LTS induction. The larynx was visualized 2, 4 and 6 weeks after treatment. Six weeks post-treatment, the larynges were evaluated histologically.

RESULTS

BMSCs were adhered to culture flasks, spindle shape and positive for mesenchymal marker and negative for hematopoietic markers. Osteogenic induction was verified by Alizarin red staining. Karyotype was normal. A complete epithelialization and minimal chronic inflammatory cell infiltration were noted in submucosa of both left (control) and right (cases) vocal folds. The healing effect of conditioned media and BMSCs in comparison to the control group was more prominent.

CONCLUSION

As thickness of fibrosis in cases were less than control group, conditioned media and BMSCs were shown to be good choices in healing of LTS.

Growth kinetics and characterization of human dental pulp stem cells: Comparison between third molar and first premolar teeth

Background

Dental pulp stem cells (DPSCs) play an important role in tissue regeneration. This study compares the growth kinetics and characterization of third molar and first premolar human DPSCs.

Material and Methods

Dental pulp tissues were isolated from human first premolar and third molar teeth and were digested by treating them with collagenase type I. Single-cell suspensions from each dental pulp were seeded in T25 culture flasks and the media were replaced every 3 days until 70% confluence. The cells were enumerated to determine the population doubling time (PDT). Cells were characterized using flow cytometry, RT-PCR and osteogenic medium for differentiation of DPSCs. Karyotyping assay was also performed till passage 7th.

Results

The DPSCs had spindle-shaped morphology. There was an increase in PDT in third molar DPSCs when compared to first premolar teeth. Positive expression of CD44, CD73, and CD90 and negative expression of CD34 and CD45 were illustrated. A normal karyotype was visible for all seven passages. The Alizarin red staining was positive for osteogenic induction of DPSCs.

Conclusions

When DPSCs are needed, third molar teeth can be a good and convenient candidate for cell transplantation, yielding high number of cells with mesenchymal characteristics. They can be a source for further investigations in vitro and work on tissue engineering protocols.

Key words:Stem cells, dental pulp, growth kinetics, characterization.

Comparison of Renal Growth, Proteinuria and Graft Survival between Recipients of Pediatric and Adult Cadaveric Kidney Transplants

BACKGROUND

The shortage of cadaveric kidney donors has prompted transplant teams to expanding the donor selection criteria. The usage of pediatric cadaveric kidneys is one of those expanded criteria. But the main concern is the probability of hyperfiltration syndrome due to small renal mass of pediatric donors.

OBJECTIVE

To compare the graft and patient survivals, post-transplantation complications, rate and severity of proteinuria secondary to hyperfiltration injury and the kidney growth of recipients who underwent transplantation from adult (group 1) and pediatric deceased donors (group 2).

METHODS

In this historical cohort study, each group contains 36 patients. Outcome measures included patient and graft survivals, quality of graft function as assessed by serum creatinine (SCr) and estimated GFR (eGFR), surgical complications, proteinuria that was detected by routine urinalysis and then confirmed by a 24-h urine protein >150 mg, blood pressure, and kidney length and volume measured by early and follow-up ultrasonography.

RESULTS

The mean donor age in groups 1 and 2 was 36 and 6.5 years, respectively. 9 (25%) kidneys taken from pediatric donors (group 2) were offered en-bloc. The mean follow-up was 28 month. The two groups were not significantly different in terms of the incidence of DGF, rate of acute rejection, 1-year graft survival, SCr and eGFR levels, rates of surgical complications requiring surgical interventions, development of proteinuria, and rate of post-transplantation rise in blood pressure. The mean±SD kidney length within 24 hours of transplantation was significantly higher in group 1 compared to group 2 recipients (112±14 vs. 75±12 mm; p=0.001), but the rate of increase in kidney length in group 2 was significantly higher than that in group 1 recipients (43±4 vs. 10±2 mm; p=0.002) during the follow-up period. 80% of the increase in the kidney size was observed during the first 12 months of surgery; another 20% happened between 12 and 18 months.

CONCLUSION

We found that obligatory and compensatory growth of pediatric kidney donors can overcome the concern of hyperfiltration syndrome and that the outcome is the same as adult donors.

The healing effect of bone marrow-derived stem cells in acute radiation syndrome

Objectives:

To determine the effect of bone marrow-derived mesenchymal stem cells (BMSCs) on regeneration of bone marrow and intestinal tissue and survival rate in experimental mice with acute radiation syndrome (ARS).

Methods:

Forty mice were randomly divided into two equal groups of A receiving no BMSC transplantation and B receiving BMSCs. BMSCs were isolated from the bone marrow and cultured in DMEM media. Both groups were irradiated with 10 Gy (dose rate 0.28 Gy/ min) ⁶⁰CO during 35 minutes with a field size of 35×35 for all the body area. Twenty-four hours after γ irradiation, 150×10³ cells of passage 5 in 150 µl medium were injected intravenously into the tail. Animals were euthanized one and two weeks after cell transplantation. They were evaluated histologically for any changes in bone marrow and intestinal tissues. The survival rate in mice were also determined.

Results:

A significant increase for bone marrow cell count and survival rate were observed in group B in comparison to group A. Histological findings denoted to a healing in sample tissues.

Conclusion:

BMSCs could significantly reduce the side effects of ARS and increase the survival rate and healing in injured tissue. As such their transplantation may open a window in treatment of patients with ARS.

Histomorphometric evaluation of treatment of rat azoosper-mic seminiferous tubules by allotransplantation of bone marrow-derived mesenchymal stem cells

OBJECTIVES

Bone marrow-derived mesenchymal stem cells (BM-MSCs) potentials make them appropriate for cell therapy including ability of differentiation and release of anti-inflammatory cytokines and growth factors secreta. For treatment of azoospermia to induce proliferation and differentiation of germ cells, MSCs transplantation has been introduced. The aim of the present experimental case-control study was to histomorphometric evaluation of the germinal cells in seminiferous tubules of azoospermic rats before and after BM-MSCs allotransplantation.

MATERIALS AND METHODS

In the present study, BM-MSCs were isolated from six male rats and confirmed. Their testes also served as intact negative controls. The recipient rats (n=6) were received two doses of 10 mg/kg of busulfan with 21 days interval to induce azoospermia. After cessation of spermatogenesis, the rats were allotransplanted with the BM-MSCs into efferent duct of right testes. Thirty-five days later, the right cell-treated testes were compared to left azoospermic ones.

RESULTS

Histomorphometric analyses showed that the seminiferous tubules treated with BM-MSCs had normal morphology in comparison with azoospermic testes, which were without germinal layer. In most BM-MSCs-treated seminiferous tubules, spermatogenesis was observed.

CONCLUSION

The allotransplanted BM-MSCs could induce spermatogenesis in seminiferous tubules of azoospermic rats.

The Healing Effect of Bone Marrow-Derived Stem Cells in Knee Osteoarthritis: A Case Report

Osteoarthritis (OA) is a prevalent chronic disease impacting on quality of life and has societal and economical burden increasing with age. Yet, no confirmed pharmacological, biological or surgical therapy could prevent the progressive destruction of OA joint. Mesenchymal stem cells (MSCs) with immunosuppressive activities emerged a potential therapy. We describe a magnetic resonance images (MRI) approved 47 years old nomad female suffering from a severe right knee OA. After intra-articular injection of 36×10(6) passage 2 of bone marrow-derived stem cells (BMSCs), the patient's functional status of the knee, the number of stairs she could climb, the pain on visual analog scale (VAS) and walking distance improved after two months post-transplantation. MRI revealed an extension of the repaired tissue over subchondral bone. So as MSC transplantation is a simple technique, resulted into pain relief, minimized donor-site morbidity, provided a better quality of life, significantly improved cartilage quality with no need to hospitalization or surgery, cell transplantation can be considered as a reliable alternative treatment for chronic knee OA. Therefore these findings can be added to the literature on using BMSCs for treatment of OA.

Growth Kinetics, Characterization, and Plasticity of Human Menstrual Blood Stem Cells

One of the readily available sources of mesenchymal stem cells (MSCs) is menstrual blood-derived stem cells (Men-SCs), which exhibit characteristics similar to other types of MSCs. This study was performed to determine the growth kinetics, plasticity, and characterization of Men-SCs in women. During spring 2014 in the southern Iranian city of Shiraz, menstrual blood (5 mL) was obtained from 10 women on their third day of menstruation in 2 age groups of 30 to 40 and 40 to 50 years old. Ficoll was used to separate the mononuclear cell fraction. After the Men-SCs were cultured, they were subcultured up to passage 4. Growth behavior and population doubling time were evaluated by seeding 5×10(4) cells into 12- and 24-well culture plates, and the colonies were enumerated. The expression of CD44, CD90, and CD34 was evaluated. The osteogenic potential was assessed by alizarin red staining. The Men-SCs were shown to be plastic adherent and spindle-shaped. Regarding the growth curves in the 12- and 24-well culture plates, it was demonstrated that in the women aged between 30 and 40 years, population doubling time was 55.5 and 62 hours, respectively, while these values in the women aged between 40 and 50 years were 70.4 and 72.4 hours, correspondingly. Positive expression of CD44 and CD90 and negative expression of CD34 were noted. In the osteogenic differentiation medium, the cells differentiated toward osteoblasts. As human Men-SCs are easily collectable without any invasive procedure and are a safe and rapid source of MSCs, they can be a good candidate for stem cell banking and cell transplantation in women.

Induction of Spermatogenesis by Bone Marrow-derived Mesenchymal Stem Cells in Busulfan-induced Azoospermia in Hamster

Background

Bone marrow-derived mesenchymal stem cells (BM-MSCs) have potential of differentiation and they secrete anti-inflammatory cytokines and growth factors which make them appropriate for cell therapy.

Aim of the Work

Were to evaluate the healing effect of BM-MSCs transplantation on germinal cells of busulfan-induced azoospermic hamsters.

Material and Methods

In the present experimental case control study, BM-MSCs were isolated from bone marrow of donor albino hamsters. Five mature male recipient hamsters received two doses of 10 mg/kg of busulfan with 21 days interval to stop endogenous spermatogenesis. After induction of azoospermia, right testis of hamsters was injected with 10⁶ BM-MSCs via efferent duct and the left one remained as azoospermia control testis. Five normal mature hamsters were selected as normal intact control. After 35 days, testes and epididymis of three groups were removed for histological evaluation.

Results

Histomorphological analyses of BM-MSCs treated testes and epididymis showed the epithelial tissue of seminiferous tubules had normal morphology and spermatozoa were present in epididymis tubes. Spermatogenesis was observed in most cell-treated seminiferous tubules. The untreated seminiferous tubules were empty.

Conclusion

Transplanted BM-MSCs could successfully induce spermatogenesis in seminiferous tubules of azoospermic hamster. Therefore, BM-MSCs can be an attractive candidate in cell transplantation of azoospermia.

Adipose tissue-derived mesenchymal stem cells repair germinal cells of seminiferous tubules of busulfan-induced azoospermic rats

CONTEXT:

Adipose tissue-derived mesenchymal stem cells (AT-MSCs) are less invasive than bone marrow mesenchymal stem cells to obtain for cell therapy.

AIMS:

The aims of this study were to evaluate the germinal cells characteristics and repairs in seminiferous tubules of busulfan-induced azoospermic rats after AT-MSCs transplantation.

SETTINGS AND DESIGN:

Experimental case-control study.

MATERIALS AND METHODS:

In the present experimental study, donors AT-MSCs were isolated from subcutaneous adipose tissue of two Sprague-Dawley rats. The recipients (n = 5) were received two doses of 10 mg/kg of busulfan with 21 days interval to stop endogenous spermatogenesis. After induction of azoospermia by busulfan, rats were injected with the AT-MSCs into the efferent duct of right testes. After 60 days, the right testes were injected AT-MSCs were compared to left azoospermic testes. Five untreated male rats served as negative control.

STATISTICAL ANALYSIS USED:

Stereological indices were analyzed by one-way ANOVA and LSD post-hoc test. The spermatogenesis index was compared using Mann–Whitney U test.

RESULTS:

After stereological analyses, the seminiferous tubules treated with AT-MSCs had normal morphology. The untreated seminiferous tubules were empty. Spermatogenesis was observed in most cell-treated seminiferous tubules.

CONCLUSIONS:

The testis of busulfan-induced azoospermic rats accepted transplanted AT-MSCs. The transplanted AT-MSCs could induce spermatogenesis in seminiferous tubules of the rat.

The Healing Effect of Adipose-Derived Mesenchymal Stem Cells in Full-thickness Femoral Articular Cartilage Defects of Rabbit

BACKGROUND

Articular cartilage defect can lead to degradation of subchondral bone and osteoarthritis (OA).

OBJECTIVE

To determine the healing effect of transplantation of adipose-derived mesenchymal stem cells (Ad-MSCs) in full-thickness femoral articular cartilage defects in rabbit.

METHODS

12 rabbits were equally divided into cell-treated and control groups. In cell-treated group, 2×10(6) cells of third passage suspended in 1 mL of DMEM was injected into articular defect. The control group just received 1 mL of DMEM. Dulbecco's modified Eagles medium (DMEM) supplemented with 10% fetal bovine serum (FBS), 1% penicillin and streptomycin and 2 mM L-glutamine were used for cell culture. To induce cartilage defect, 4 mm articular cartilage full-thickness defect was created in the knee. For histological evaluation in each group (H&E, safranin-O and toluidine blue), 3 rabbits were sacrificed 4 weeks and 3 animals, 8 weeks after cell transplantation.

RESULTS

In cell therapy group post-transplantation, no abnormal gross findings were noticed. Neo-formed tissues in cell-treated groups were translucent with a smooth and intact surface and less irregularity. In cell-treated group after 8 weeks post-transplantation, the overall healing score of experimental knees were superior when compared to other groups.

CONCLUSION

We showed that Ad-MSCs, as an available and non-invasive produced source of cells, could be safely administered in knee osteochondral defects.

Protective effects of Cornus mas fruit extract on carbon tetrachloride induced nephrotoxicity in rats

Oxidative damage is implicated in the pathogenesis of kidney injury. Cornus mas is used for in renal aliments traditionally in Iran. The present study was aimed to investigate the antioxidant activity of C. mas fruit extract (CMFE) on carbon tetrachloride (CCl₄) treated oxidative stress in Wistar albino rats. Forty two male albino rats were divided into seven groups. Group I served as a sham; Group II served as a normal control; Group III served as a toxic control, with CCl₄ (1 ml/kg body weight; 80% in olive oil); Groups IV and V received CMFE at doses of 300 and 700 mg/kg before CCl₄ injection; Groups VI and VII received extract at same doses orally at 2, 6, 12, 24 and 48 h after CCl₄ intoxication. CCl₄ injection produced a significant rise in serum markers of oxidative stress and lipid peroxidation product malondialdehyde along with the reduction of antioxidant enzymes such as superoxide dismuta, catalase and glutathion peroxidase. Serum creatinine, urea and uric acid concentrations were increased whereas level of protein and albumin were reduced. Treatment of rats with different doses of fruit extract (300 and 700 mg/kg) significantly (P < 0.05) ameliorated the alterations induced with CCl₄ in lipid peroxidation, antioxidant defenses, biochemical and renal lesions. Based on these results, we conclude that CMFE protects kidney from oxidative stress induced by CCl₄.

First identification of Sarcocystis hominis in Iranian traditional hamburger

Zoonotic concerns of cattle sarcocystosis are of importance, because humans are the final host for Sarcocystis hominis. Therefore the meat products containing beef may encompass sarcocysts which endanger food safety. In this study, we described the first report of molecular identification of S. hominis in Iranian traditional hamburgers using PCR-RFLP. Throughout a pilot research that was carried out to setup a molecular approach to identify the Sarcocystis spp., using PCR-RFLP, a sample of raw Iranian traditional hamburger was purchased from a street food seller located in Yazd, central Iran in May 2013. DNA extraction was done, by salting out method; briefly, the sample was lysed with NET buffer. The DNA purification and precipitation was then performed. Amplicon and digestion results were analyzed, using gel agarose electrophoresis. The results showed a PCR product with 926 bp in length after amplification and 376 and 550 bp in length after digestion. This product was identified as S. hominis. To the best of our knowledge, this is the first report of S. hominis infection in Iranian hamburger.