Zinc Sulphate Mediates the Stimulation of Cell Proliferation of Rat Adipose Tissue-Derived Mesenchymal Stem Cells Under High Intensity of EMF Exposure

The Cellular Response Is Determined by a Combination of Different ELF-EMF Exposure Parameters: A Scope Review

Since the establishment of regulations for exposure to extremely low-frequency (0-300) Hz electromagnetic fields, scientific opinion has prioritised the hypothesis that the most important parameter determining cellular behaviour has been intensity, ignoring the other exposure parameters (frequency, time, mode, waveform). This has been reflected in the methodologies of the in vitro articles published and the reviews in which they are included. A scope review was carried out, grouping a total of 79 articles that met the proposed inclusion criteria and studying the effects of the different experiments on viability, proliferation, apoptosis, oxidative stress and the cell cycle. These results have been divided and classified by frequency, intensity, exposure time and exposure mode (continuous/intermittent). The results obtained for each of the processes according to the exposure parameter used are shown graphically to highlight the importance of a good methodology in experimental development and the search for mechanisms of action that explain the experimental results, considering not only the criterion of intensity. The consequence of this is a more than necessary revision of current exposure protection regulations for the general population based on the reductionist criterion of intensity.

System-level biological effects of extremely low-frequency electromagnetic fields: an in vivo experimental review

During the past decades, the potential effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health have gained great interest all around the world. Though the International Commission on Non-Ionizing Radiation Protection recommended a 100 μT, and then a 200 μT magnetic field limit, the long-term effects of ELF-EMFs on organisms and systems need to be further investigated. It was reported that both electrotherapy and possible effects on human health could be induced under ELF-EM radiation with varied EM frequencies and fields. This present article intends to systematically review the in vivo experimental outcome and the corresponding mechanisms to shed some light on the safety considerations of ELF-EMFs. This will further advance the subsequent application of electrotherapy in human health.

Zinc enhances the cell adhesion, migration, and self-renewal potential of human umbilical cord derived mesenchymal stem cells

BACKGROUND

Zinc (Zn) is the second most abundant trace element after Fe, present in the human body. It is frequently reported in association with cell growth and proliferation, and its deficiency is considered to be a major disease contributing factor.

AIM

To determine the effect of Zn on in vitro growth and proliferation of human umbilical cord (hUC)-derived mesenchymal stem cells (MSCs).

METHODS

hUC-MSCs were isolated from human umbilical cord tissue and characterized based on immunocytochemistry, immunophenotyping, and tri-lineage differentiation. The impact of Zn on cytotoxicity and proliferation was determined by MTT and Alamar blue assay. To determine the effect of Zn on population doubling time (PDT), hUC-MSCs were cultured in media with and without Zn for several passages. An in vitro scratch assay was performed to analyze the effect of Zn on the wound healing and migration capability of hUC-MSCs. A cell adhesion assay was used to test the surface adhesiveness of hUC-MSCs. Transcriptional analysis of genes involved in the cell cycle, proliferation, migration, and self-renewal of hUC-MSCs was performed by quantitative real-time polymerase chain reaction. The protein expression of Lin28, a pluripotency marker, was analyzed by immunocytochemistry.

RESULTS

Zn at lower concentrations enhanced the rate of proliferation but at higher concentrations (> 100 µM), showed concentration dependent cytotoxicity in hUC-MSCs. hUC-MSCs treated with Zn exhibited a significantly greater healing and migration rate compared to untreated cells. Zn also increased the cell adhesion rate, and colony forming efficiency (CFE). In addition, Zn upregulated the expression of genes involved in the cell cycle (CDC20, CDK1, CCNA2, CDCA2), proliferation (transforming growth factor β1, GDF5, hypoxia-inducible factor 1α), migration (CXCR4, VCAM1, VEGF-A), and self-renewal (OCT4, SOX2, NANOG) of hUC-MSCs. Expression of Lin28 protein was significantly increased in cells treated with Zn.

CONCLUSION

Our findings suggest that zinc enhances the proliferation rate of hUC-MSCs decreasing the PDT, and maintaining the CFE. Zn also enhances the cell adhesion, migration, and self-renewal of hUC-MSCs. These results highlight the essential role of Zn in cell growth and development.

ZINC (Zn) AND ADIPOSE-DERIVED MESENCHYMAL STEM CELLS (AD-MSCs) ON MPTP-INDUCED PARKINSON'S DISEASE MODEL: A COMPARATIVE EVALUATION OF BEHAVIORAL AND IMMUNOHISTOCHEMICAL RESULTS

Parkinson's disease (PD) is characterized by the loss of dopaminergic neurons and sustained neuroinflammation due to microglial activation. Adipose tissue-derived mesenchymal stem cells (AD-MSCs) secrete neuroprotective factors to prevent neuronal damage. Furthermore, Zn regulates stem cell proliferation and differentiation and has immunomodulatory functions. Our in vivo study aimed to investigate whether Zn affects the activities of AD-MSCs in the MPTP-induced mouse model. Male C57BL/6 mice were randomly divided into six groups (n=6): Control, Zn, PD, PD+Zn, PD+(AD-MSC), PD+(AD-MSC)+Zn. MPTP toxin (20mg/kg) was dissolved in saline and intraperitoneally injected into experimental groups for two days with 12h intervals. On the 3rd day, AD-MSCs were given to the right lateral ventricle of the PD+(AD-MSC) and PD+(AD-MSC)+Zn groups by stereotaxic surgery. Then, ZnSO₄H₂O was administered intraperitoneally for 4 days at 2mg/kg. Seven days post MPTP injection, the motor activities of the mouse were evaluated. Then immunohistochemical analyzes were performed in SNpc. Our results showed that motor activity was lower in Group PD. AD-MSC and Zn administration have improved this impairment. MPTP caused a decrease in TH and BDNF expressions in dopaminergic neurons in Group PD. However, TH and BDNF expressions were more intense in the other groups. MCP-1, TGF-β, and IL-10 expressions increased in administered groups compared to the Group PD. The present study indicates that Zn's individual and combined administration with AD-MSCs reduces neuronal damage in the MPTP-induced mouse model. In addition, anti-inflammatory responses that emerge with Zn and AD-MSCs may have a neuroprotective effect.

The Effects of Quercetin on Apoptosis and Antioxidant Activity in a Renal Ischemia/Reperfusion Injury Animal Model

Renal ischemia-reperfusion injury (IRI) is considered as one of the most prevalent causes of acute kidney injury (AKI), which can happen in various clinical situations including hypovolemic shock, injury, thrombo-embolism, and after a kidney transplant. This paper aims to evaluate the reno-protective effects of Quercetin in induced ischemia/reperfusion injury by regulating apoptosis-related proteins, inflammatory cytokines, MMP-2, MMP-9, and nuclear factor kappa-light-chain-enhancer inactivated B cells (NF-kB) in rats. The male Wistar rats (n=32) were randomly divided into Sham, untreated IR, and Quercetin-treated IR (gavage and intraperitoneal). Quercetin was given orally and intraperitoneally one hour before inducing ischemia-reperfusion injury . After reperfusion, blood samples and kidneys were collected to assess renal function and inflammatory cytokines, apoptotic signaling proteins, and antioxidants. Urea, creatinine, and MDA levels improved in Quercetin-treated groups with different administration methods. In addition, the activities of other antioxidant in Quercetin-treated rats were higher than those in the IR group. Further, Quercetin inhibited NF-kB signaling, apoptosis-associated factors and produced matrix metalloproteinase protein in the kidneys of rats. Based on the findings, the antioxidant, anti-inflammatory, and anti-apoptotic effects of the Quercetin diminished renal ischemia-reperfusion injury in the rats significantly. It is suggested that a single dosage of Quercetin have a reno-protective impact in the case of renal I/R injury.

Zinc and hypoxic preconditioning: a strategy to enhance the functionality and therapeutic potential of bone marrow-derived mesenchymal stem cells

The therapeutic use of bone marrow mesenchymal stem cells (BM-MSCs) requires a large number of cells (1-100 × 10⁶ cells/kg of body weight). Extensive in vitro growth is limited due to the aging of cultured BM-MSCs which leads to abnormal morphology and senescence. Hypoxia increases BM-MSC proliferation, but the question of whether hypoxia preconditioning is safe for clinical application of BM-MSCs remains to be answered. Zinc is essential for cell proliferation and differentiation, especially for the regulation of DNA synthesis and mitosis. It is a structural constituent of numerous proteins on a molecular level, including transcription factors and enzymes of cellular signaling machinery. All the tissues, fluids, and organs of the human body contain zinc. More than 95% of zinc is intracellular, of which 44% is involved in the transcription of DNA. We investigated the effects of ZnCl₂ on proliferation, morphology, migration, population doubling time (PDT), and gene expression of BM-MSCs under hypoxic (1% O₂) and normoxic (21% O₂) environments. BM-MSCs were preconditioned with optimized concentrations of ZnCl₂ under normoxic and hypoxic environments and further examined for morphology by the phase-contrast inverted microscope, cell proliferation by MTT assay, PDT, cell migration ability, and gene expression analysis. Zinc significantly enhanced the proliferation of BM-MSCs, and it decreases PDT under hypoxic and normoxic environments as compared to control cells. Migration of BM-MSCs toward the site of injury increased and expression of HIF1-α significantly decreased under hypoxic conditions as compared to non-treated hypoxic cells and control. At late passages (P₉), the morphology of normoxic BM-MSCs was transformed into large, wide, and flat cells, and they became polygonal and lost their communication with other cells. Conversely, zinc-preconditioned BM-MSCs retained their spindle-shaped, fibroblast-like morphology at P₉. The expression of proliferative genes was found significantly upregulated, while downregulation of genes OCT4 and CCNA2 was observed in zinc-treated BM-MSCs under both normoxic and hypoxic conditions. ZnCl₂ treatment can be used for extensive expansion of BM-MSCs in aged populations to obtain a large number of cells required for systemic administration to produce therapeutic efficacy.

Validation of a color deconvolution method to quantify MSC tri-lineage differentiation across species

Mesenchymal stem cells (MSCs) are a promising candidate for both human and veterinary regenerative medicine applications because of their abundance and ability to differentiate into several lineages. Mesenchymal stem cells are however a heterogeneous cell population and as such, it is imperative that they are unequivocally characterized to acquire reproducible results in clinical trials. Although the tri-lineage differentiation potential of MSCs is reported in most veterinary studies, a qualitative evaluation of representative histological images does not always unambiguously confirm tri-lineage differentiation. Moreover, potential differences in differentiation capacity are not identified. Therefore, quantification of tri-lineage differentiation would greatly enhance proper characterization of MSCs. In this study, a method to quantify the tri-lineage differentiation potential of MSCs is described using digital image analysis, based on the color deconvolution plug-in (ImageJ). Mesenchymal stem cells from three species, i.e., bovine, equine, and porcine, were differentiated toward adipocytes, chondrocytes, and osteocytes. Subsequently, differentiated MSCs were stained with Oil Red O, Alcian Blue, and Alizarin Red S, respectively. Next, a differentiation ratio (DR) was obtained by dividing the area % of the differentiation signal by the area % of the nuclear signal. Although MSCs isolated from all donors in all species were capable of tri-lineage differentiation, differences were demonstrated between donors using this quantitative DR. Our straightforward, simple but robust method represents an elegant approach to determine the degree of MSC tri-lineage differentiation across species. As such, differences in differentiation potential within the heterogeneous MSC population and between different MSC sources can easily be identified, which will support further optimization of regenerative therapies.

The Role of Zinc in Bone Mesenchymal Stem Cell Differentiation

Zinc is an essential trace element for bone growth and bone homeostasis in the human body. Bone mesenchymal stem cells (BMSCs) are multipotent progenitors existing in the bone marrow stroma with the capability of differentiating along multiple lineage pathways. Zinc plays a paramount role in BMSCs, which can be spurred differentiating into osteoblasts, chondrocytes, or adipocytes, and modulates the formation and activity of osteoclasts. The expression of related genes also changed during the differentiation of various cell phenotypes. Based on the important role of zinc in BMSC differentiation, using zinc as a therapeutic approach for bone remodeling will be a promising method. This review explores the role of zinc ion in the differentiation of BMSCs into various cell phenotypes and outlines the existing research on their molecular mechanism.

Osteogenic ability using porous hydroxyapatite scaffold-based delivery of human placenta-derived mesenchymal stem cells

Previous preliminary studies have suggested that hydroxyapatite with a grooved structure (HAG) scaffold has good osteogenic potential. This type of scaffold may aid osteogenesis during the repair of large maxillofacial bony defects. The ectopic osteogenic effect and underlying mechanism were further studied using porous HAG scaffold-based delivery of human placenta-derived mesenchymal stem cells (hPMSCs). A total of 18 dogs were randomly allocated into a HAG scaffold group and a HAG scaffold-based hPMSC (HAG/hPMSC) group, and three scaffolds were implanted into the dorsal muscle of each dog. Samples were taken for subsequent analysis and tested 4, 8 and 12 weeks following heterotopic implantation. H&E staining was used to study the osteogenic effect in dog dorsal muscles, and RNA sequencing (RNA-seq) was used for exploring the underlying osteogenic mechanism. The osteogenic ability and effector of the HAG/hPMSC group were significantly greater than those of the HAG scaffold group at 4 weeks after implantation. After 12 weeks, a mature bone plate structure was seen in the HAG/hPMSC group. RNA-seq demonstrated that various osteogenesis-related pathways participated at different stages of metabolism, and that the expression of collagen-1 and runt-related transcription factor 2 increased with implantation time. The present study preliminarily focused on the ectopic osteogenic effect of the porous HAG scaffold-based delivery of hPMSCs in vivo, which may be helpful for the improved application of HAG scaffolds in the future.

Renoprotective effects of prazosin on ischemia-reperfusion injury in rats

BACKGROUND

Renal ischemia-reperfusion (IR) injury is one of the main leading causes of acute kidney injury associated with inflammation, oxidative stress and cell apoptosis. We studied the effects of prazosin, as a specific blocker of α1-AR, on renal IR injury.

METHODS

Rats were divided into normal control; untreated IR and prazosin-treated IR (1 mg/kg body weight). Prazosin was administered by intraperitoneal injection 30 min prior to IR induction. The level of urea/creatinine and oxidative factors were detected by colorimetric methods. Apoptosis-associated factors, inflammatory, and signaling proteins were analyzed in renal tissue. The abnormalities of renal histopathology were detected by immunohistochemistry.

RESULTS

Administration of prazosin to IR rats ameliorated serum urea and creatinine and IR-induced histopathological damages. Lipid peroxidation was significantly improved after treatment by prazosin in IR injury rats, however, antioxidant status was not affected. Rats subjected to IR injury activated Bax protein and NF-κB mediated inflammatory response. Moreover, treatment with prazosin inhibited renal NF-κB activation, resulting in a significant decline in pro-inflammatory cytokine of IL-6.

CONCLUSION

These findings suggest that prazosin could be a good candidate to attenuate renal IR injury due to its ability to modulate renal function, apoptosis and inflammation.

Transfection of TGF-β shRNA by Using Ultrasound-targeted Microbubble Destruction to Inhibit the Early Adhesion Repair of Rats Wounded Achilles Tendon In vitro and In vivo

BACKGROUND

Tendon injury is a major orthopedic disorder. Ultrasound-targeted microbubble destruction (UTMD) provides a promising method for gene transfection, which can be used for the treatment of injured tendons.

OBJECTIVE

The purpose of this study was to investigate the optimal transforming growth factor beta (TGF-β) short hairpin RNA (shRNA) sequence and transfection conditions using UTMD in vitro and to identify its ability for inhibiting the early adhesion repair of rats wounded achilles tendons in vivo.

METHODS

The optimal sequence was selected analyzing under a fluorescence microscope and quantitative real-time reverse transcription polymerase chain reaction in vitro. In vivo, 40 rats with wounded Achilles tendons were divided into five groups: (1) control group, (2) plasmid group (3) plasmid + ultrasound group, (4) plasmid + microbubble group, (5) plasmid + microbubble + ultrasound group, and were euthanized at 14 days post treatment. TGF-β expression was evaluated using adhesion scores and pathological examinations.

RESULTS

The optimal condition for UTMD delivery in vitro was 1W/cm2 of output intensity and a 30% duty cycle with 60 s irradiation time (P < 0.05). The transfection efficiency of the plasmid in group 5 was higher than that in other groups (P < 0.05). Moreover, the lowest adhesion index score and the least expression of TGF-β were shown in group 5 (P < 0.05). When compared with the other groups, group 5 had a milder inflammatory reaction.

CONCLUSION

The results suggested that UTMD delivery of TGF-β shRNA offers a promising treatment approach for a tendon injury in vivo.

Effects of Achillea tenuifolia Lam. hydro-alcoholic extract on anxiety-like behavior and reproductive parameters in rat model of chronic restraint stress

INTRODUCTION

Achillea tenuifolia Lam (AT) has several biological activities and medicinal properties. In this study, we elucidated the impact of the AT on anxiety-related behaviors, reproductive parameters, antioxidant capacity in male rats subjected to chronic restraint stress (CRS).

METHODS

35 Wistar rats were divided into five groups: control, CRS-control (received normal saline) and three CRS-treated groups received AT extract (100, 150, and 200 mg/kg body weight) for 21 consequences days. To induce CRS rats, the rats were immobilized for 21 days and received the extract orally. On the last day of treatment, anxiety-related behaviors were assessed through the sucrose preference test (SPT) as well as elevated plus maze (EPM) tests. Corticosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH), testosterone levels were evaluated to determine reproductive capacity. Sperm parameters including the total count, motility, and viability were also analyzed. Weight of body, testis and seminal vesicles was measured as well.

RESULTS

The findings revealed that 100, 150, and 200 mg/kg of AT extract had anxiolytic effects in CRS rats, as confirmed by the EPM test and SPT. In addition, AT extract could improve fertile capacity and sperm quality to varying degrees. The level of corticosterone had decreased, whereas the level of LH, FSH and testosterone had increased in CRS-treated rats. Moreover, the reduced level of MDA coincided with an increased rate of antioxidant capacity. Our findings suggest that AT extract could alleviate stress-induced dysfunctions.

CONCLUSION

Overall, these observations would infer that AT extract could improve fertility capacity and behavioral impairment in the stress conditions.

GRAPHICAL ABSTRACT

Assumption pathway describing the probability underlying mechanism of CRS-induced anxiety and reproductive toxicity and protective effect of AT.

Understanding stem cells and its pivotal role in regenerative medicine

Stem cells (SCs) are clonogenic cells that develop into the specialized cells which later responsible for making up various types of tissue in the human body. SCs are not only the appropriate source of information for cell division, molecular and cellular processes, and tissue homeostasis but also one of the major putative biological aids to diagnose and cure various degenerative diseases. This study emphasises on various research outputs that occurred in the past two decades. This will give brief information on classification, differentiation, detection, and various isolation techniques of SCs. Here, the various signalling pathways which includes WNT, Sonic hedgehog, Notch, BMI1 and C-met pathways and how does it effect on the regeneration of various classes of SCs and factors that regulates the potency of the SCs are also been discussed. We also focused on the application of SCs in the area of regenerative medicine along with the cellular markers that are useful as salient diagnostic or curative tools or in both, by the process of reprogramming, which includes diabetes, cancer, cardiovascular disorders and neurological disorders. The biomarkers that are mentioned in various literatures and experiments include PDX1, FOXA2, HNF6, and NKX6-1 (for diabetes); CD33, CD24, CD133 (for cancer); c-Kit, SCA-1, Wilm's tumor 1 (for cardiovascular disorders); and OCT4, SOX2, c-MYC, EN1, DAT and VMAT2 (for neurological disorders). In this review, we come to know the advancements and scopes of potential SC-based therapies, its diverse applications in clinical fields that can be helpful in the near future.

Mesenchymal Stem Cells Promote Caspase Expression in Molt-4 Leukemia Cells Via GSK-3α/Β and ERK1/2 Signaling Pathways as a Therapeutic Strategy

BACKGROUND

Mesenchymal stem cells (MSCs) are considered an interesting tool in cell therapy due to their unique features such as self-renewal, multi-potency, and pluripotency. The multifunctional properties of these cells are being investigated in many studies. The current research examined the influence of MSCs on the Molt-4 cell line as acute lymphoblastic leukemia (ALL) cells.

METHODS

MSCs were cultured, characterized, and co-cultured with Molt-4 cells in a trans-well system. Then, cultured Molt-4 alone and Molt-4 co-cultured with MSCs (10:1) were collected on day 7 and subjected to western blotting for protein expression assessment. Telomerase activity as well as cell senescence, were investigated by PCR-ELISA TRAP assay and β-galactosidase activity measurement, respectively.

RESULTS

It was found that MSCs resulted in a significant increase in the pro-caspase-8 and cleaved-caspase 8 and 9 expression levels. Furthermore, protein expression levels of GSK-3α/β and ERK1/2 were significantly decreased. The results also showed that MSCs caused significant decreases and increases in telomerase and β-galactosidase enzyme activity of Molt-4 cells, respectively.

CONCLUSION

It was concluded that MSCs co-cultured with Molt-4 cells could be involved in the promotion of Molt-4 cell apoptosis and cell senescence via caspase-8, 9 cascade and GSK-3α/β and ERK1/2 signaling pathways.

Comparative study of gavage and intraperitoneal administration of gamma-oryzanol in alleviation/attenuation in a rat animal model of renal ischemia/reperfusion-induced injury

OBJECTIVES

Ischemia/reperfusion (I/R) is the leading cause of acute kidney injury. This study aimed to elucidate the reno-protective effect of gamma-oryzanol (GO) by comparing gavage and intraperitoneal (IP) administration methods on renal I/R injury in a rat model.

MATERIALS AND METHODS

Rats were divided into four groups including (group 1) sham, (group 2) I/R-control, (group 3) I/R+GO gavage-treated, and (group 4) I/R+ GO IP-treated. A single dose of GO was administrated to groups 3 and 4 (100 mg/kg body weight), 60 min before induction of I/R. After anesthesia, I/R was created by 45 min of ischemia, followed by 6 hr of reperfusion. Then, blood and tissue samples were subjected to evaluation of renal function, anti-oxidant capacity, inflammation, apoptotic proteins, and IKB/NF-kB pathway.

RESULTS

The two GO administration methods showed improvement of renal function along with attenuation of histological abnormalities. An increase in antioxidant capacity along with a decrease in pro-inflammatory markers, decline in the expression levels of BAX, Bax/Bcl-2, and caspase-3, and up-regulation of Bcl-2 expression were recorded. Moreover, a significant decrease in NF-Kb, p-IKBα, and MMP-2/9 with an increase in IKBα levels were also observed. Overall, in a comparative evaluation between the two gavage and IP administration methods, we did not find any differences in all examined parameters, except IL-6 which had a better result via gavage.

CONCLUSION

A single dose of GO administration has a reno-protective effect against renal I/R injury. Gavage and IP administration exhibit similar efficiency in alleviation of I/R injury.

Extremely Low-Frequency Magnetic Field as a Stress Factor-Really Detrimental?-Insight into Literature from the Last Decade

Biological effects of extremely low-frequency magnetic field (ELF-MF) and its consequences on human health have become the subject of important and recurrent public debate. ELF-MF evokes cell/organism responses that are characteristic to a general stress reaction, thus it can be regarded as a stress factor. Exposure to ELF-MF "turns on" different intracellular mechanisms into both directions: compensatory or deleterious ones. ELF-MF can provoke morphological and physiological changes in stress-related systems, mainly nervous, hormonal, and immunological ones. This review summarizes the ELF-MF-mediated changes at various levels of the organism organization. Special attention is placed on the review of literature from the last decade. Most studies on ELF-MF effects concentrate on its negative influence, e.g., impairment of behavior towards depressive and anxiety disorders; however, in the last decade there was an increase in the number of research studies showing stimulating impact of ELF-MF on neuroplasticity and neurorehabilitation. In the face of numerous studies on the ELF-MF action, it is necessary to systematize the knowledge for a better understanding of the phenomenon, in order to reduce the risk associated with the exposure to this factor and to recognize the possibility of using it as a therapeutic agent.

Immunomodulatory and Antioxidative potentials of adipose-derived Mesenchymal stem cells isolated from breast versus abdominal tissue: a comparative study

BACKGROUND

Adipose-derived stem cells (ASCs) are considered ideal candidates for both research and cellular therapy due to ease of access, large yield, feasibility, and efficacy in preclinical and clinical studies. Unlike the subcutaneous abdominal fat depot, breast ASCs features are still not well recognized, limiting their possible therapeutic use. ASCs were found to exert immunomodulatory and antioxidative activities for maintaining homeostasis and functionality of diseased/damaged tissues. This study aims to investigate the immunomodulatory and antioxidative potentials of breast versus abdominal isolated ASCs to find out which anatomical site provides ASCs with better immunoregulatory and oxidative stress resistance capabilities.

METHODS

ASCs were isolated from abdominal and breast tissues. Gene expression analysis was conducted for a panel of immunomodulatory and antioxidative genes, as well as adipokines and proliferation genes. Flow cytometric analysis of a group of immunomodulatory surface proteins was also performed. Finally, the significantly expressed genes have undergone protein-protein interaction and functional enrichment in silico analyses.

RESULTS

Our results revealed similar morphological and phenotypic characteristics for both breast and abdominal ASCs. However, a significant elevation in the expression of two potent immunosuppressive genes, IL-10 and IDO as well as the expression of the multifaceted immunomodulatory adipokine, visfatin, was detected in breast versus abdominal ASCs. Moreover, a significant overexpression of the antioxidative genes, GPX1, SIRT5, and STAT3 and the proliferation marker, Ki67, was also observed in breast ASCs relative to abdominal ones. In silico analysis showed that both of the differentially upregulated immunomodulatory and antioxidative mediators integratively involved in multiple biological processes and pathways indicating their functional association.

CONCLUSION

Breast ASCs possess superior immunomodulatory and antioxidative capabilities over abdominal ASCs. Our findings shed light on the possible therapeutic applications of breast ASCs in immune-related and oxidative stress-associated diseases.

Senescent mesenchymal stem/stromal cells and restoring their cellular functions

Mesenchymal stem/stromal cells (MSCs) have various properties that make them promising candidates for stem cell-based therapies in clinical settings. These include self-renewal, multilineage differentiation, and immunoregulation. However, recent studies have confirmed that aging is a vital factor that limits their function and therapeutic properties as standardized clinical products. Understanding the features of senescence and exploration of cell rejuvenation methods are necessary to develop effective strategies that can overcome the shortage and instability of MSCs. This review will summarize the current knowledge on characteristics and functional changes of aged MSCs. Additionally, it will highlight cell rejuvenation strategies such as molecular regulation, non-coding RNA modifications, and microenvironment controls that may enhance the therapeutic potential of MSCs in clinical settings.

L-carnitine Extends the Telomere Length of the Cardiac Differentiated CD117+- Expressing Stem Cells

Stem cell-based therapy has emerged as an attractive method for regenerating and repairing the lost heart organ. On other hand, poor survival and maintenance of the cells transferred into the damaged heart tissue are broadly accepted as serious barriers to enhance the efficacy of the regenerative therapy. For this reason, external factors, such as antioxidants are used as a favorite strategy by the investigators to improve the cell survival and retention properties. Therefore, the present study was conducted to investigate the In -vitro effect of L-carnitine (LC) on the telomere length and human telomerase reverse transcriptase (hTERT) gene expression in the cardiac differentiated bone marrow resident CD117⁺ stem cells through Wnt3/β-catenin and ERK1/2 pathways. To do this, bone marrow resident CD117⁺ stem cells were enriched by the magnetic-activated cell sorting (MACS) method, and were differentiated to the cardiac cells in the absence (-LC) and presence of the LC (+LC). Also, characterization of the enriched c-kit⁺ cells was performed using the flow cytometry and immunocytochemistry. At the end of the treatment period, the cells were subjected to the real-time PCR technique along with western blotting assay for measurement of the telomere length and assessment of mRNA and protein, respectively. The results showed that 0.2 mM LC caused the elongation of the telomere length and increased the hTERT gene expression in the cardiac differentiated CD117⁺ stem cells. In addition, a significant increase was observed in the mRNA and protein expression of Wnt3, β-catenin and ERK1/2 as key components of these pathways. It can be concluded that the LC can increase the telomere length as an effective factor in increasing the cell survival and maintenance of the cardiac differentiated bone marrow resident CD117⁺ stem cells via Wnt3/β-catenin and ERK1/2 signaling pathway components.

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

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

Interleukin-6, -8, and TGF-β Secreted from Mesenchymal Stem Cells Show Functional Role in Reduction of Telomerase Activity of Leukemia Cell Via Wnt5a/β-Catenin and P53 Pathways

Purpose: The effect of mesenchymal stem cells (MSCs) on the immortality features of malignant cells, such as hematologic cancerous cells, are controversial, and the associated mechanisms are yet to be well understood. The aim of the present study was to investigate the in vitro effect of bone marrow-derived MSCs (BMSCs) on the chronic myeloid leukemia cell line K562 through telomere length measurements, telomerase activity assessments, and hTERT gene expression. The possible signaling pathways involved in this process, including Wnt-5a/β-catenin and P53, were also evaluated.

Methods: Two cell populations (BMSCs and K562 cell line) were co-cultured on transwell plates for 7 days. Next, K562 cells were collected and subjected to quantitative real-time PCR, PCR-ELISA TRAP assay, and the ELISA sandwich technique for telomere length, hTERT gene expression, telomerase activity assay, and cytokine measurement, respectively. Also, the involvement of the mentioned signaling pathways in this process was reported by real-time PCR and Western blotting through gene and protein expression, respectively.

Results: The results showed that BMSCs caused significant decreases in telomere length, telomerase activity, and the mRNA level of hTERT as a regulator of telomerase activity. The significant presence of interleukin (IL)-6, IL-8, and transforming growth factor beta (TGF-β) was obvious in the co-cultured media. Also, BMSCs significantly decreased and increased the gene and protein expression of β-catenin and P53, respectively.

Conclusion: It was concluded that the mentioned effects of IL-6, IL-8, and TGF-β cytokines secreted from MSCs on K562 cells as therapeutic agents were applied by Wnt-5a/β-catenin and P53 pathways

Mesenchymal stem cells in acute myeloid leukemia: a focus on mechanisms involved and therapeutic concepts

Drug resistance in cancer, especially in leukemia, creates a dilemma in treatment planning. Consequently, studies related to the mechanisms underlying drug resistance, the molecular pathways involved in this phenomenon, and alternate therapies have attracted the attention of researchers. Among a variety of therapeutic modalities, mesenchymal stem cells (MSCs) are of special interest due to their potential clinical use. Therapies involving MSCs are showing increasing promise in cancer treatment and anticancer drug screening applications; however, results have been inconclusive, possibly due to the heterogeneity of MSC populations. Most recently, the effect of MSCs on different types of cancer, such as hematologic malignancies, their mechanisms, sources of MSCs, and its advantages and disadvantages have been discussed. There are many proposed mechanisms describing the effects of MSCs in hematologic malignancies; however, the most commonly-accepted mechanism is that MSCs induce tumor cell cycle arrest. This review explains the anti-tumorigenic effects of MSCs through the suppression of tumor cell proliferation in hematological malignancies, especially in acute myeloid leukemia.

Stem cell-based regenerative medicine

Recent developments in the stem cell biology provided new hopes in treatment of diseases and disorders that yet cannot be treated. Stem cells have the potential to differentiate into various cell types in the body during age. These provide new cells for the body as it grows, and replace specialized cells that are damaged. Since mesenchymal stem cells (MSCs) can be easily harvested from the adipose tissue and can also be cultured and expanded in vitro they have become a good target for tissue regeneration. These cells have been widespread used for cell transplantation in animals and also for clinical trials in humans. The purpose of this review is to provide a summary of our current knowledge regarding the important and types of isolated stem cells from different sources of animal models such as horse, pig, goat, dog, rabbit, cat, rat, mice etc. In this regard, due to the widespread use and lot of attention of MSCs, in this review, we will elaborate on use of MSCs in veterinary medicine as well as in regenerative medicine. Based on the studies in this field, MSCs found wide application in treatment of diseases, such as heart failure, wound healing, tooth regeneration etc.

Cytokines secreted from bone marrow derived mesenchymal stem cells promote apoptosis and change cell cycle distribution of K562 cell line as clinical agent in cell transplantation

Mesenchymal stem cells (MSCs) are of special interest due their potential clinical use in cell-based therapy. Therapies engaging MSCs are showing increasing promise in the cancer treatment and anticancer drug screening applications. A multitude of growth factors and cytokines secreted from these cells are known to give such multifunctional properties, but details of their role are yet to be absolutely demonstrated. In this study, we have evaluated the influence of BMSCs on K562 cell line as chronic myeloid leukemia (CML) cells, with the use of a cytokine antibody array recognizing 34 cytokines. For this purpose, BMSCs were isolated and co-cultured with K562 cells; thereafter, cultured K562 alone and co-cultured K562 with BMSCs (10:1) were collected at day 7 and subjected to cell cycle distribution assay as well as annexin/PI analysis and Ki/caspase-3 assay for apoptosis assessment. In the following, the gene and protein expression levels of BAX and BCL-2 as pro- and anti-apoptotic agents were investigated. Furthermore, after 7 days’ treatment, culture medium was collected from both control and experimental groups for cytokine antibody array. It was found that BMSCs resulted in a robust increase in the number of cells at G₀/G₁ phase and arrest the G₀/G₁ phase as well as significantly inducing late apoptosis in K562 cells. The significant presence of TIMP-1 (tissue inhibitor of metalloproteinases-1), and moderate elevated signals for CINC-1 (cytokine-induced neutrophil chemoattractant-1) were obvious in the co-cultured conditioned media, but no significant increase was found in 32 other cytokines. It is concluded that co-culture of BMSCs with K562 cells could secrete a substantial amount of TIMP-1 and CINC-1. These cytokines could be involved in the inhibition of the K562 cell proliferation via BAX and caspase-3 cascade pathways.

Telomere shortening as a hallmark of stem cell senescence

Stem cells, especially mesenchymal stem cells (MSCs)-based therapies have been greatly attentioned in regenerative medicine through multi-lineage differentiation, self-renewal properties, etc. Despite the above advantages of MSCs, the defined properties of these cells are strongly affected by aging. Thus, the use of MSCs from older donors is lower than younger one, which limits clinical applications in cell therapy. According to the theories of aging, it is determined that aging is most likely caused by telomere shortening and telomere shortening is considered hallmarks of aging. Finding out the most mechanisms of these changes will probably reveal novel therapeutic targets for prolonging human health and for ameliorating age-associated phenotypes. This review focuses on prevalent knowledge about the mechanisms of stem cell senescence by telomere shortening and the molecular mechanism details involved in it.

Anti-aging protective effect of L-carnitine as clinical agent in regenerative medicine through increasing telomerase activity and change in the hTERT promoter CpG island methylation status of adipose tissue-derived mesenchymal stem cells

The identification of factors that reduce the senescent tendency of the mesenchymal stem cells (MSCs) upon expansion has great potential for cellular therapies in regenerative medicine. Previous studies have shown the aging protective effect of L-carnitine (LC). On the other hand, reduction in proliferation potential and age-dependent decline in number and functions of MSCs were accompanied by telomere shortening, reduction in telomerase activity and epigenetic changes. The aim of this study was to evaluate the effects of LC on aging of MSCs through telomerase activity assessment and the investigation of methylation status of the hTERT gene promoter. Telomerase activity and hTERT promoter methylation investigation was performed with PCR-ELISA TRAP assay and methylation specific PCR (MSP), respectively. Also, beta-galactosidase (SA-ß-gal) staining was used to calculate the percentage of senescent cells. The results showed that the LC could efficiently promote the telomerase activity. In addition, the percentage of senescent cells had significantly decreased and changes in the methylation status of the CpG islands in the hTERT promoter region under treatment with LC were seen. In conclusion, it seems that LC could improve the aging-related features due to increasing the telomerase activity, decreasing aging, and changing the methylation status of hTERT promoter; it could potentially beneficial for enhancing the application of aged-MSCs in regenerative medicine.