Synthesis of novel hybrids of 1,2,3-triazoles-hydrazone: targeting cholinesterases and Alzheimer's related genes.

Aim: A new series of 1,2,3-triazole-hydrazone derivatives were developed to evaluate their anti-Alzheimer's activity. Materials & methods: All compounds were screened toward cholinesterases via the modified Ellman's method. The toxicity assay on SH-SY5Y cells was performed using the MTT assay, and the expression levels of GSK-3α, GSK-3ß, DYRK1 and CDK5 were assessed in the presence of compounds 6m and 6p. Results: 6m and 6p; acting as mixed-type inhibitors, exhibited promising acetylcholinesterase and butyrylcholinesterase inhibitory activity, respectively. 6m demonstrated no toxicity under tested concentrations on the SH-SY5Y cells and positively impacted neurodegenerative pathways. Notably, 6m displayed a significant downregulation in mRNA levels of GSK-3α, GSK-3ß and CDK5. Conclusion: The target compounds could be considered in developing anti-Alzheimer's disease agents.

[Box: see text].

The impact of acemannan, an extracted product from Aloe vera, on proliferation of dental pulp stem cells and healing of mandibular defects in rabbits.

OBJECTIVES: Dental pulp stem cells (DPSCs) were shown to play an important role in regenerative medicine including reconstruction of various bone lesions. This study determined the impact of acemannan, an extracted product from Aloe vera, on in vitro proliferation of DPSCs and in vivo healing of mandibular defects in rabbits. METHODS: DPSCs were isolated and characterized. The growth kinetics of cells exposed to acemannan (8 mg/mL) and Hank's balanced salt solution (HBSS) were compared in vitro. Fifteen male rabbits were divided into 3 groups. Five animals were left as control group without any therapeutic intervention. Five rabbits were considered as experimental group 1 and received 20 µL of a cell suspension containing 106 DPSCs in the bone defect. Another 5 rabbits were regarded as experimental group 2 and were injected in the bone defect with 20 µL of a cell suspension containing 106 DPSCs treated with acemannan for 24 h. After 60 days, the animals were assessed by radiography and histologically. RESULTS: The mesenchymal properties of DPSCs were confirmed. Population doubling time (PDT) of DPSCs treated with acemannan (29.8 h) was significantly shorter than cells were just exposed to HBSS (45.9 h). DPSCs together with acemannan could significantly accelerate the healing process and osteogenesis in mandibular defects. CONCLUSIONS: As DPSCS showed an increased proliferation when treated with acemannan and accelerated the healing process in mandibular defects, these findings can open a new avenue in dentistry regenerative medicine when remedies of bone defects are targeted.

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 (ß-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/ß-TCP scaffold, a stem cell-loaded 3D-printed nHA/ß-TCP scaffold, and a cell-free collagen-coated 3D-printed nHA/ß-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/ß-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/ß-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.

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?

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.

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.

Phenyl-quinoline derivatives as lead structure of cholinesterase inhibitors with potency to reduce the GSK-3ß 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-3ß 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.

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 Ki 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.

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.

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.

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.

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.

Superparamagnetic Iron Oxide-Labeled Leishmania major Can Be Traced in Fibroblasts.

Introduction: Leishmaniasis is still a neglected tropical disease that can endanger more than 350 million people among 98 countries. Leishmania can survive in fibroblasts as latent inactive forms. This study was conducted to evaluate the role of superparamagnetic iron oxide nanoparticles (SPIONs) in cell culture for tracking the labeled Leishmania major in fibroblasts. Methods: Dextran-coated SPIONs were used for labeling L. major in co-culture of fibroblasts with the parasite. To quantify and trace SPION-labeled Leishmania, Prussian blue staining was undertaken. Fibroblast characterization was undertaken by real time polymerase chain reaction. Transmission electron microscope (TEM) was used for confirming the entry of the labeled L. major to the cytoplasm and the nucleus of the fibroblast. Results: Fibroblasts were spindle-shaped and adherent to culture flasks. Promastigotes were with thin elongated lance-like morphology with an anterior kinetoplast and an emergent free flagellum. Prussian blue staining revealed that internalized SPIONs were localized within cytoplasm and nucleus of the fibroblasts after 24 hours of culture. Prussian blue staining successfully showed the presence of iron (stained blue) in labeled L. major within the fibroblasts. This finding was confirmed by TEM, and labeled L. major was detected in the fibroblast cytoplasm and nucleus too. Conclusion: We can conclude that SPIONs are safe, inexpensive, easy to use, and accurate, and a fast method to label Leishmania parasite in cells that the parasite can be latent, such as fibroblasts. These findings can open a new window in diagnosis, pathogenesis, and treatment of cutaneous leishmaniasis and can be added to the literature.

MRI tracking of human Wharton's jelly stem cells seeded onto acellular dermal matrix labeled with superparamagnetic iron oxide nanoparticles in burn wounds.

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.

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.

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.

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.

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.