Effect of Rat Bone Marrow Derived-Mesenchymal Stem Cells on Granulocyte Differentiation of Mononuclear Cells as Preclinical Agent in Cellbased Therapy

STAT1 inhibition promotes oxidative stress to sustain leukemia stem cell maintenance

New strategy to prevent relapse and drug resistance in acute myeloid leukemia (AML) is urgently to be solved. The connection between those properties and leukemia stem cells (LSCs) in AML remains poorly understood. In this study, we demonstrate that leukemia cells with high signal transducer and activator of transcription 1 (STAT1) expression preserve quiescent properties, in contrast, leukemia cells with low STAT1 expression possess active and vulnerable apoptotic properties in AML model, highlighting the differential impact of STAT1 expression on cellular behavior in acute myeloid leukemia. STAT1 depletion damages the quiescence of LSCs and prolongs the survive of AML mice. By inhibiting STAT1 in leukemia cells, we observe a significant elevation in reactive oxygen species (ROS) levels, rendering the cells more susceptible to the detrimental effects of oxidative stress. The synergistic administration of Fludarabine, a potent STAT1 inhibitor, with conventional chemotherapy regimens, augments the efficacy of chemotherapy drugs against AML cells and the sensitivity of LSCs to chemotherapy. In a word, STAT1, as a switch, enables leukemia cells convertible in ROS high and low states. Inhibition of STAT1 enables leukemia cells more sensitive to chemotherapy, STAT1 as a new target offers a promising strategy in AML treatment.

SERCA-mediated endoplasmic reticulum stress facilitates hematopoietic stem cell mobilization

BACKGROUND

Hematopoietic stem cell (HSC) transplantation is widely recognized as an effective treatment for various malignant diseases. Enhancing HSC mobilization can improve transplantation outcomes and ultimately increase patient survival rates. Recent studies suggest that mild endoplasmic reticulum (ER) stress promotes HSC self-renewal, anti-apoptotic, and anti-aging capabilities. This led us to investigate whether inducing mild ER stress could facilitate HSC mobilization.

METHODS

The phenotype changes in cells treated with ER stress inducers and Sarco/endoplasmic reticulum Ca²⁺-ATPase (SERCA) inhibitors were assessed using flow cytometry. The efficacy of these agents on HSC mobilization was evaluated in C57Bl/6 mice, with colony forming unit (CFU) assays used for quantification. Knockdown Jurkat cell lines were constructed to validate the role of SERCA in the mobilization mechanism. Molecular and protein expression levels associated with the pathway were analyzed through quantitative reverse-transcription PCR and western blotting.

RESULTS

Our findings revealed that BHQ, a SERCA inhibitor, efficiently enhanced HSC mobilization in vivo. Mechanistically, BHQ regulated the CaMKII-STAT3-CXCR4 pathway by suppressing SERCA activity. This inhibition led to a reduction in CXCR4 expression on the surface of HSCs, facilitating their migration from the bone marrow into peripheral circulation.

CONCLUSIONS

Our study provides novel insights into the role of the SERCA-ER stress pathway in HSC mobilization. By targeting SERCA activity with BHQ, we observed a significant enhancement in the mobilization of HSCs, facilitated by the modulation of the CaMKII-STAT3-CXCR4 signaling pathway. This research highlights the potential of utilizing mild ER stress as a strategy to promote HSC mobilization, with significant implications for improving stem cell-based therapies, including those used in HSC transplantation.

Extracellular vesicles from mesenchymal stem cells improve liver injury in rats with mild liver damage. Underlying mechanisms and role of TGFβ

Preventing the progression of liver damage to fibrosis would be beneficial for patients with steatotic liver disease (SLD). Mesenchymal stem cells (MSC) are a promising therapy for SLD and derived extracellular vesicles (EVs) could even improve the treatment's efficacy and safety. However, the mechanisms of MSC-EVs beneficial effects are not well known. It has been suggested that modifying the EVs cargo could improve their beneficial effects. The aims of this study were to assess if MSC-EVs reduce liver damage in a rat model of mild liver damage; to analyze the underlying mechanisms and to assess if silencing TGFβ enhances the beneficial effects of MSC-EVs. CCl4 was injected three times per week during four weeks to induce mild liver damage. EVs from human adipocyte MSC and from TGFβ-depleted MSC (siTGFβ-MSC-EVs) were injected in the tail vein. Steatosis, fibrosis, liver inflammation, macrophage infiltration and liver content of fibrotic markers, DAMPs, cytokines and bile acids were analyzed. Normal MSC-EVs reduce the CCL2 increase in liver, macrophage infiltration and the increases in the fibrosis markers collagen I and α-SMA. Treatment with siTGFβ-MSC-EVs, in addition, reduces liver steatosis, the increase of bile acids (mainly TCA), and DAMP HMGB1 levels, inducing a larger reduction of collagen I in liver of CCl4 rats. Treatment with MSCs-EVs effectively reduces early liver damage. Silencing of TGFβ in MSCs enhances the beneficial effects by additional mechanisms. Early treatment with MSC-EVs, especially after silencing TGFβ, could improve liver damage in SLD patients.

Clofarabine-loaded aptamer-conjugated biodegradable nanoparticle successfully targeted CD117 overexpressed HL60 cells and potentially induced apoptosis

Acute Myeloid Leukemia (AML) is a rapidly progressing malignancy characterized by the proliferation of abnormal neutrophils, leading to severe symptoms and complications. Current widely used treatment options include chemotherapy and radiotherapy, which often result in suffering from systemic toxicity and drug resistance. To mitigate systemic toxicity and off-target side effects, a targeted therapeutic strategy is one of the remarkably successful options. For targeting AML cells, we have chosen a single-strand DNA aptamer (Apt), which is specific for the biomarker CD117, overexpressing AML cells. This study introduces explicitly a novel therapeutic approach employing aptamer-conjugated clofarabine-loaded PLGA nanoparticles (Apt-CNP) targeting the CD117 receptor on HL60 leukemia cells. Clofarabine, a potent nucleoside analogue, disrupts DNA synthesis and induces cancer cell death but is limited by its toxicity and resistance. Encapsulation in PLGA nanoparticles enables sustained drug release, maintaining therapeutic concentrations and potentially reducing drug resistance. Our findings demonstrate that Apt-CNP effectively targets HL60 leukemia cells, thereby improving drug delivery and reducing adverse effects on healthy cells. This targeted approach may open a new avenue for more specific drug delivery to mobile and floated blood cells, including AML (HL60 leukemia) cells, and overcome the limitations of traditional AML treatments.

Donor age and breed determine mesenchymal stromal cell characteristics

BACKGROUND

Mesenchymal stromal cells (MSCs) hold significant potential for various applications in regenerative medicine and tissue engineering. Initially considered as a single cell type with defined characteristics, MSCs are now known as a heterogeneous cell population with remarkable differences in their properties. No consensus exists on how donor age affects MSC characteristics, like proliferation. Additionally, differences in differentiation capacities and immunophenotype could arise when MSCs are isolated from different animals breeds, which is relevant for experimental and preclinical studies of MSC-based treatments.

METHODS

In this study, we isolated bovine adipose tissue-derived MSCs from three age categories, i.e. fetal, calf, and adult, and of two different breeds, i.e. Holstein Friesian (HF) and Belgian Blue (BB). MSC characterization included tri-lineage differentiation, proliferation and senescence assays, and immunophenotyping using multi-color flow cytometry.

RESULTS

Especially fetal and calf HF-MSCs showed a high proliferation capacity, where 4 and 6 out of 7 donors, respectively, could surpass 30 population doublings. Adipogenic differentiation potential was higher for fetal and adult HF-MSCs. Furthermore, breed, but not age, affected their osteogenic differentiation potential, with BB-MSCs performing better. Evaluation of cell surface marker expression revealed a breed effect, as calf HF-MSCs showed a higher percentage of Cluster of Differentiation (CD)34+ cells compared to calf BB-MSCs, which was correlated with both osteogenic differentiation and proliferation potential.

CONCLUSIONS

Our findings clearly show the impact of donor characteristics such as age and breed on MSC proliferation, immunophenotype, and differentiation potential, illustrating the importance of selecting the appropriate MSC donor for MSC-based treatments when allogeneic MSCs are considered.

Use of quantum hyperlight technology in photobiomodulation on stem cells: an experimental in vitro study

Human umbilical cord matrix Wharton's jelly mesenchymal stem cells (WJ-MSCs) are commonly utilized in regenerative medicine due to their therapeutic benefits. However, the microenvironmental stress present in patients with hyperglycemia can significantly reduce mesenchymal stem cell (MSC) viability under high-glucose conditions in the body, ultimately reducing their therapeutic effectiveness. Enhancing the survival rate of MSCs following cell transplantation remains a crucial challenge. This study investigates whether Quantum Hyperlight (QHL) can counteract the detrimental effects of high glucose (HG), thereby improving MSC survival, proliferation, and mitochondrial function. We aimed to evaluate the effect of QHL on cellular viability, proliferation, and mitochondrial activity in WJ-MSCs exposed to HG. MSCs were cultured in a medium containing normal glucose (NG) (1 g/L) and HG (4.5 g/L). MSCs in the HG medium were exposed to QHL for 90 s or 180 s with an energy density of 2.4 Joules/cm2/minute and an average power density of 40 mW/cm2. Then, proliferating cell nuclear antigen (PCNA), MTT assays, and Mitotracker Green staining were performed to evaluate cell viability and proliferation. The viability of MSCs was significantly increased in the QHL-treated groups (84% in QHL-90 s and 86% in QHL-180 s) compared to the untreated HG group (65%, p < 0.001). PCNA expression in QHL-90 s and QHL-180 s groups showed significant increases (p < 0.001) compared to the untreated HG group. MitoTracker staining intensity was significantly higher in the QHL-treated groups compared to the untreated HG group (p < 0.001). The HG environment reduced viability, proliferation, and mitochondrial staining. In the context of the NG environment, MSCs exhibited notable differences. However, the viability, proliferation, and mitochondrial staining rates of MSCs were significantly higher in the HG conditions when treated with QHL compared to the group that did not receive QHL. This study introduces QHL as a novel approach to enhance the therapeutic potential of WJ-MSCs under HG conditions, demonstrating its ability to improve cellular viability, proliferation, and mitochondrial activity. This study highlights its potential as a pretreatment to improve clinical outcomes in regenerative medicine.

CircSPG21 ameliorates oxidative stress-induced senescence in nucleus pulposus-derived mesenchymal stem cells and mitigates intervertebral disc degeneration through the miR-217/SIRT1 axis and mitophagy

BACKGROUND

The microenvironment of intervertebral disc degeneration (IVDD) is characterized by oxidative stress, leading to the senescence of nucleus pulposus-derived mesenchymal stem cells (NPMSCs). The purpose of this study was to investigate the competitive endogenous RNA mechanism involved in the senescence of NPMSCs induced by tert-butyl hydroperoxide (TBHP).

METHODS

Bioinformatic analysis identified differentially expressed circRNAs. Interactions among circSPG21, miR-217, and the NAD-dependent protein deacetylase sirtuin-1 (SIRT1) were validated through dual-luciferase assays, RNA fluorescence in situ hybridization and RNA immune precipitation. β-Gal staining, EdU staining, Western blotting, JC-1 assays, cell cycle analysis, and quantitative reverse transcription PCR (RT‒qPCR) were used to examine the functions of these molecules in TBHP-induced senescent NPMSCs. The therapeutic effects of circSPG21 were evaluated in a rat IVDD model.

RESULTS

CircSPG21 expression was significantly decreased in both human and rat IVDD tissues, whereas miR-217 was upregulated and SIRT1 was downregulated. Overexpression of circSPG21 alleviated NPMSC senescence by reducing P21 and P53 levels and restoring mitophagy through Parkin. The protective effects of circSPG21 were mediated through the miR-217/SIRT1 axis, as SIRT1 knockdown attenuated these benefits. CircSPG21 also ameliorated disc degeneration in the IVDD rat model, highlighting its potential as a therapeutic target.

CONCLUSION

CircSPG21 reduces oxidative stress-induced NPMSC senescence through the miR-217/SIRT1 axis and mitophagy, providing new insights into IVDD and identifying circSPG21 as a potential therapeutic target for disc degeneration.

Effect of CD10-positive cells on osteogenic differentiation of human maxillary/mandibular bone marrow-derived mesenchymal stem cells

OBJECTIVE

This study was aimed at investigating the effect of CD10-positive cells within the maxillary/mandibular bone marrow-derived mesenchymal stem cells (MBMSCs) on osteogenic differentiation of MBMSCs.

DESIGN

CD10 expression in iliac bone marrow-derived MSCs (IBMSCs), MBMSCs, and gingival fibroblasts was measured using flow cytometry. The osteogenic potential of 19 MBMSC lines was evaluated, and based on it, they were classified into osteogenic-High and osteogenic-Low groups. The percentage of CD10-positive cells in each group was compared. Effect of coculturing gingival fibroblasts and CD10-positive cells on the osteogenic potential of MBMSCs was also assessed. Expression of tissue inhibitor of metalloprotease-1 (TIMP-1) in osteogenic-High and osteogenic-Low MBMSCs was measured using quantitative real-time polymerase chain reaction, western blotting, and enzyme-linked immunosorbent assay. The molecular mechanisms underlying the regulation of osteogenic differentiation in MBMSCs were investigated.

RESULTS

CD10 was not expressed in IBMSCs, but was highly expressed in fibroblasts. In MBMSCs, the CD10-positivity rate varied considerably between cells. MBMSCs with a high-CD10 positivity rate showed low osteogenic potential. Coculture with fibroblasts or CD10-positive cells reduced the osteogenic potential of MBMSCs. TIMP-1 was highly expressed in CD10-positive cells, and osteogenic-Low MBMSCs showed significantly higher TIMP-1 expression compared with osteogenic-High MBMSCs. β-catenin signaling was suppressed in osteogenic-Low MBMSCs.

CONCLUSION

This study revealed that TIMP-1 secreted from CD10-positive cells may be involved in the suppression of the osteogenic potential of MBMSCs by contamination with CD10-positive cells. This finding provides important insights for developing bone regeneration therapies using MBMSCs.

Enhanced fetal hemoglobin production via dual-beneficial mutation editing of the HBG promoter in hematopoietic stem and progenitor cells for β-hemoglobinopathies

BACKGROUND

Sickle cell disease (SCD) and β-thalassemia patients with elevated gamma globin (HBG1/G2) levels exhibit mild or no symptoms. To recapitulate this natural phenomenon, the most coveted gene therapy approach is to edit the regulatory sequences of HBG1/G2 to reactivate them. By editing more than one regulatory sequence in the HBG promoter, the production of fetal hemoglobin (HbF) can be significantly increased. However, achieving this goal requires precise nucleotide conversions in hematopoietic stem and progenitor cells (HSPCs) at therapeutic efficiency, which remains a challenge.

METHODS

We employed Cas9 RNP-ssODN-mediated homology-directed repair (HDR) gene editing to mimic two naturally occurring HBG promoter point mutations; -175T > C, associated with high HbF levels, and -158 C > T, a common polymorphism in the Indian population that induces HbF under erythropoietic stress, in HSPCs.

RESULTS

Asymmetric, nontarget ssODN induced high rates of complete HDR conversions, with at least 15% of HSPCs exhibiting both the -175T > C and -158 C > T mutations. Optimized conditions and treatment with the small molecule AZD-7648 increased this rate, with up to 57% of long-term engrafting human HSPCs in NBSGW mice containing at least one beneficial mutation. Functionally, in vivo erythroblasts exhibited high levels of HbF, which was sufficient to reverse the cellular phenotype of β-thalassemia. Further support through bone marrow MSC co-culture boosted complete HDR conversion rates to exceed 80%, with minimal InDels, improved cell viability, and induced fetal hemoglobin levels similar to those of Cas9 RNP-mediated indels at BCL11A enhancer and HBG promoter.

CONCLUSIONS

Cas9 RNP-ssODN-based nucleotide conversion at the HBG promoter offers a promising gene therapy approach to ameliorate the phenotypes of β-thalassemia and SCD. The developed approach can simplify and broaden applications that require the cointroduction of multiple nucleotide modifications in HSPCs.

Co-Colorectal cancer stem cells employ the FADS1/DDA axis to evade NK cell-mediated immunosuppression after co-cultured with NK cells under hypoxia

Colorectal cancer (CRC) ranks as China's second most common cancer and fifth top cancer death cause. The study highlights the role of Natural Killer (NK) cells in targeting cancer stem cells (CSCs) that evade immune responses in CRC. Colorectal cancer stem cells (CCSCs) were stem from HT-29 cells and co-cultured with NK cells under normoxic or hypoxic conditions. The impact of this co-culture was evaluated using CCK8 assays for NK cell viability, ELISA for cytokine level changes, and flow cytometry for assessing NK cell apoptosis and activation. Comprehensive metabolomic and transcriptomic analyses were also performed to identify key genes and metabolites involved in the interaction between CCSCs and NK cells Co-culture of CCSCs with NK cells under hypoxia reduced NK cytotoxicity, increased NK apoptosis, and altered cytokine secretion by decreasing IFN-γ and TNF-α levels while increasing IL-6. Transcriptomic and metabolomic analysis identified 4 genes (FADS1, ALDH3A2, GCSH, MTCL1) and 3 metabolites (glyoxylic acid, spermine, DDA) as significant. Interfering with FADS1 counteracted the suppression of IFN-γ and TNF-α induced by CSC cells. Curiously, this inhibition caused by si-FADS1 could be neutralized by the addition of exogenous DDA. Co-culturing with NK cells notably increased spermine levels. Exogenous spermine resulted in a significant reduction in HT-29 cell death rates at 32 µM, 64 µM, and 128 µM, compared to NK cells without spermine. Our research explored CCSCs employed the FADS1/DDA axis to evade NK cell-mediated immunosuppression after co-cultured with NK cells under hypoxia.

FDFT1 maintains glioblastoma stem cells through activation of the Akt pathway

BACKGROUND

Cancer stem cells (CSCs) have unique metabolic characteristics and are hypothesized to contribute significantly to the recurrence and drug resistance of glioblastoma multiforme (GBM). However, the reliance on mitochondrial metabolism and the underlying mechanism of glioblastoma stem cells (GSCs) remains to be elucidated.

METHODS

To quantify differential mitochondrial protein expression between GSCs and differentiated cells, a mass spectrum screen was applied by the Stable Isotope Labeling with Amino Acids in Cell Culture (SILAC) technique. Functional experiments including CCK8, neurosphere formation, flow cytometry, transwell, and wound healing assays were conducted to evaluate GBM cell malignant phenotype. The potential molecular mechanism of FDFT1 was screened by RNA-seq analyses. The candidate target genes were validated through RT-qPCR and western blot analyses.

RESULTS

As a top candidate, FDFT1 protein expression in GSCs was elevated relative to their differentiated counterparts. Functionally, the knockdown of FDFT1 suppressed the GBM cell proliferation and migration, while simultaneously enhancing sensitivity to temozolomide. Treatment with both the FDFT1 inhibitor (YM-53601) and simvastatin (an HMG-CoA reductase inhibitor) induced apoptosis in GSCs. Mechanistically, FDFT1 was transcriptionally regulated by SREBP2 but not SREBP1. Furthermore, FDFT1 activates the AKT pathway to regulate tumor metabolism and maintain the stemness of tumor cells.

CONCLUSIONS

GSCs exhibit a dependency on FDFT1-mediated mevalonate metabolism. Inhibition of FDFT1 could represent a potent strategy to eliminate GSCs.

Eltrombopag restores proliferative capacity and adipose-osteogenic balance of mesenchymal stromal cells in low-risk myelodysplastic syndromes

In low-risk myelodysplastic syndromes (MDS), the proinflammatory signaling is excessive, and the proliferation and differentiation potentials of mesenchymal stromal cells (MSCs) are strongly impaired. Eltrombopag (ELT) has been demonstrated recently effective and relatively safe in low-risk MDS with severe thrombocytopenia. However, its impact on the MDS-MSCs has not been investigated in any detail. Here, for the first time, we investigated the changes induced by ELT in MSCs' viability, proliferation, apoptosis, senescence, multilineage differentiation properties, and stem cell support capacity in low-risk MDS patients. We demonstrated that ELT may act on improving the impaired inflammatory profile and reactivating the downregulated canonical WNT signaling pathway in low-risk MDS, and also restoring the self-renewal capacity and the balance in adipose-osteogenic differentiation of MDS-MSCs.

L-carnitine cause to increase cell proliferation of C-Kit+ hematopoietic progenitor cells via decreasing the PI3K and FOXO-1 protein expression

BACKGROUND

Stem cell-based therapy has emerged as an attractive approach for regenerative medicine. Poor survival and maintenance of the cells used in regenerative medicine are considered as serious barriers to enhance the efficacy of the cell therapy. Using some antioxidants has been reported to prevent the aging of stem cells, and finding effective factors to reduce the senescence of these cells has impressive potential in cell therapy. The PI3K pathway adversely regulates the transcription factors known as FOXO, which are thought to have an inhibitory influence on cell proliferation. By downregulating FOXO and other targets, PI3K signaling controls the growth of cells. For this reason, the aim of the present study is to investigate the effect of L-carnitine (LC) as antioxidant on the cell proliferation and the protein expression of PI3K and FOXO.

METHODS

For understanding the in vitro effect of LC on the PI3K and FOXO-1 expression of C-kit+ hematopoietic progenitor cells, the bone marrow mononuclear cells were isolated, and C-kit+ cells was enriched by the magnetic-activated cell sorting (MACS). Next, the identification of enriched C-kit+ cells were done by flowcytometry and immunocytochemistry. Then, C-kit+ cells were treated with 0.2 mM LC, the cells were collected at the end of the treatment period (48 h), and the proteins were extracted. In the following, the protein expression of PI3K and FOXO-1 was measured by western blotting. In addition, flowcytometry was done to assess the Ki-67 expression as a key marker for cell proliferation investigation.

RESULTS

0.2 mM LC cause to significantly decrease in the protein expression of PI3K and FOXO-1 (*P<0.05 and **P<0.01, respectively). Also, the expression of Ki-67 was significantly increased in the presence of 0.2 mM LC (***P<0.001).

CONCLUSION

Briefly, LC can be considered an effective factor in increasing the proliferation of C-kit+ cells via some signaling pathways.

Harnessing the therapeutic potential of bone marrow-derived stem cells for sciatic nerve regeneration in diabetic neuropathy

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes that affects the angiogenesis and myelination of peripheral nerves. In this study, we investigated the potential of mesenchymal stem cells (MSCs) transplantation to improve DPN by enhancing angiogenesis and remyelination in the sciatic nerve of streptozotocin (STZ)-induced diabetic female rats. The purpose of this study was to evaluate the therapeutic potential of mesenchymal stem cells as a possiblity for clinical intervention to alleviate the symptoms of diabetic peripheral neuropathy. We examined whether transplanted mesenchymal stem cells can produce new and restored angiogenesis, as well as promoting myelination. Overall, our findings suggest that MSCs transplantation has neuroprotective effects. This is particularly the case for Schwann cells. Transplantation may stimulate angiogenesis as well as remyelination of the sciatic nerve in experimentally-induced diabetic peripheral neuropathy. Behavioral assays, histological analysis, and molecular techniques were used to assess the effects of MSCs transplantation. Our results demonstrate that in diabetic rats signs of neuropathy were reversed following a single administration of bone marrow-derived MSCs. Morphological and morphometric analysis of the sciatic nerve revealed that diabetic rats displayed structural alterations that were attenuated with MSCs transplantation.Immunostaining analysis showed increased expression of S100 and VEGF in the sciatic nerve following MSCs transplantation. Western blotting analysis also revealed elevated levels of VEGF and CD31 in rats treated with MSCs compared to diabetic rats.

Transplantation of human umbilical cord-derived mesenchymal stem cells improves age-related ovarian functional decline via regulating the local renin-angiotensin system on inflammation and oxidative stress

BACKGROUND

Age-related reproductive aging is a natural and irreversible physiological process, and delaying childbearing is increasingly common all over the world. Transplantation of mesenchymal stem cells (MSCs) is considered a new and effective therapy to restore ovarian function, but the relevant mechanisms remain unclear. Recently, it has been found that there is a local Renin-angiotensin system (RAS) in human ovary and it plays a key role.

METHODS

After collecting follicular fluid from women who received oocyte retrieval for pure male factor infertility, the level of RAS components in it were detected, and the correlation analysis by linear regression. Then, the in vivo experiments on female C57BL/6 mice were designed to measure ovarian function, and the transcription and translation levels of RAS pathway were detected by molecular biology methods. Moreover, the role of RAS in regulating inflammation and oxidative stress in the co-culture system were explored in in vitro experiments on KGN cells.

RESULTS

First, a total of 139 samples of analyzable follicular fluid were obtained. The local RAS of ovary, which is independent of systemic RAS (P > 0.05), is affected by age (Pearson r < 0, P < 0.05) and related to ovarian function, inflammation, oxidative stress indexes and assisted reproduction laboratory outcomes (P < 0.05). Next, the ovary/body weight of aging mice decreased significantly and serum sex hormones levels changed significantly (P < 0.01). The number of functional follicles decreased, while the atresia follicles increased (P < 0.05). After MSCs transplantation, all the above measures have been partially recovered (P < 0.05). Although several RAS components in aging ovary changed, MSCs only improved the expression level of AT1R (P < 0.05). Furthermore, the secretion ability and mitochondrial membrane potential of aging KGN cells decreased, while the intracellular ROS level and the aging cells ratio increased (P < 0.01). All the above measures have been partially recovered when co-cultured with MSCs (P < 0.05). After Ang(1-7) were added into the co-culture system, the above have been more significantly restored compared with Ang II (P < 0.05). Nevertheless, there was no statistical difference in estradiol level no matter which one was added (P > 0.05).

CONCLUSIONS

Together, our findings indicate that a novel possible mechanism to explain how stem cells restore age-related ovarian functional decline.

Induction of immunogenic cell death and enhancement of the radiation-induced immunogenicity by chrysin in melanoma cancer cells

Chrysin is a natural flavonoid with anti-cancer effects. Despite its beneficial effects, little information is available regarding its immunogenic cell death (ICD) properties. In this work, we hypothesized that chrysin can potentiate radiotherapy(RT)-induced immunogenicity in melanoma cell line (B16-F10). We examined the effects of chrysin alone and in combination with radiation on ICD induction in B16-F10 cells. Cell viability was assessed using an MTT assay. Cell apoptosis and calreticulin (CRT) exposure were determined using flow cytometry. Western blotting and ELISA assay were employed to examine changes in protein expression. Combination therapy exhibited a synergistic effect, with an optimum combination index of 0.66. The synergistic anti-cancer effect correlated with increased cell apoptosis in cancer cells. Compared to the untreated control, chrysin alone and in combination with RT induced higher levels of DAMPs, such as CRT, HSP70, HMGB1, and ATP. The protein expression of p-STAT3/STAT3 and PD-L1 was reduced in B16-F10 cells exposed to chrysin alone and in combination with RT. Conditioned media from B16-F10 cells exposed to mono-and combination treatments elicited IL-12 secretion in dendritic cells (DCs), inducing a Th1 response. Our findings revealed that chrysin could induce ICD and intensify the RT-induced immunogenicity.

2-AG-loaded and bone marrow-targeted PCL nanoparticles as nanoplatforms for hematopoietic cell line mobilization

BACKGROUND

The use of mobilizing agents for hematopoietic stem cell (HSC) transplantation is insufficient for an increasing number of patients. We previously reported lipid made endocannabinoid (eCB) ligands act on the human bone marrow (hBM) HSC migration in vitro, lacking long term stability to be therapeutic candidate. In this study, we hypothesized if a novel 2-AG-loaded polycaprolactone (PCL)-based nanoparticle delivery system that actively targets BM via phosphatidylserine (Ps) can be generated and validated.

METHODS

PCL nanoparticles were prepared by using the emulsion evaporation method and characterized by Zetasizer and scanning electron microscopy (SEM). The encapsulation efficiency and release profile of 2-AG were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The presence of cannabinoid receptors (CBRs) in HSCs and monocytes was detected by flow cytometry. Cell morphology and viability were assessed using transmission electron microscopy (TEM), SEM, and the WST-1 viability assay. The migration efficacy of the 2-AG and 2-AG-loaded nanoparticle delivery system on HSCs and HPSCs (TF-1a and TF-1) and monocytes (THP-1) was evaluated using a transwell migration assay.

RESULTS

The 140-225 nm PCL nanoparticles exhibited an increasing polydispersity index (PDI) after the addition of Ps and 2-AG, with a surface charge ranging from - 25 to -50 mV. The nanoparticles released up to 36% of 2-AG within the first 8 h. The 2-AG-Ps-PCL did not affect cellular viability compared to control on days 5 and 10. The HSCs and monocytes expressed CB1R and CB2R and revealed increased migration to media containing 1 µM 2-AG-Ps-PCL compared to control. The migration rate of the HSCs toward monocytes incubated with 1 µM 2-AG-Ps-PCL was higher than that of the monocytes of control. The 2-AG-Ps-PCL formulation provided a real time mobilization efficacy at 1 µM dose and 8 h time window via a specific CBR agonism.

CONCLUSION

The newly generated and validated 2-AG-loaded PCL nanoparticle delivery system can serve as a stable, long lasting, targeted mobilization agent for HSCs and as a candidate therapeutic to be included in HSC transplantation (HSCT) protocols following scale-up in vivo preclinical and subsequent clinical trials.

Obesity modulates hematopoietic stem cell fate decision via IL-1β induced p38/MAPK signaling pathway

BACKGROUND

Obesity is accompanied by inflammation, which significantly affects the homeostasis of the immune microenvironment. Hematopoietic stem cells (HSCs), residing primarily in the bone marrow, play a vital role in maintaining and producing diverse mature blood cell lineages for the adult hematopoietic and immune systems. However, how HSCs development is affected by obese-promoting inflammation, and the mechanism by which HSC hematopoietic potency is affected by inflammatory signals originating from the obese-promoting changes on bone marrow niche remain unclear. This study elucidates the relationship between obesity-promoting inflammation and HSC fate determination.

METHODS

The obesity mice model was established by feeding C57BL/6J mice a high-fat diet (HFD) containing 60% kcal fat. After 6 weeks, HSCs were analyzed using flow cytometry and identified key inflammation cytokine. Transcriptome sequencing techniques were used to discern the distinct pathways in HSCs. Ultimately, confirming the biological mechanism of obesity-induced HSC fate changes via Anakinra blocking specific inflammatory signals.

RESULTS

Obesity caused by HFD changed the physical and biochemical properties of the bone marrow niche. In the HFD mice, the population of long-term HSCs in the bone marrow was decreased and facilitated HSCs differentiation towards the myeloid lineage. In addition, HFD increased expression of the inflammatory factor IL-1β in the bone marrow, and a significantly increased expression of IL-1r1 and active p38/MAPK signaling pathway were detected in the HSCs. Inhibition of IL-1β further normalized the expression of genes in p38/MAPK pathway and reversed HSC fate.

CONCLUSIONS

These findings have been demonstrated that the p38/MAPK signaling pathway in HSCs is activated by elevated levels of IL-1β within the HSC niche in obese models, thereby regulating HSC differentiation. It suggested a direct link between obesity-promoting inflammation and myeloid differentiation bias of HSCs in the HFD mice.

Hydrogel encapsulation of mesenchymal stem cells-derived extracellular vesicles as a novel therapeutic approach in cancer therapy

Cell therapy has emerged as one of the most promising approaches to treating disease in recent decades. The application of stem cells in anti-tumor therapy is determined by their varying capacity for proliferation, migration, and differentiation. These capacities are derived from different sources. The use of stem cell carriers in cancer treatment is justified by the following three reasons: (I) shield therapeutic agents from swift biological deterioration; (II) reduce systemic side effects; and (III) increase local therapeutic levels since stem cells have an innate ability to target tumors. The quantity of stem cells confined to the tumor microenvironment determines this system's anti-tumor activity. Nevertheless, there are limitations to the use of different types of stem cells. When immune cells are used in cell therapy, it may lead to cytokine storms and improper reactions to self-antigens. Furthermore, the use of stem cells may result in cancer. Additionally, after an intravenous injection, cells could not migrate to the injury location. Exosomes derived from different cells were thus proposed as possible therapeutic options. Exosomes are becoming more and more well-liked because of their small size, biocompatibility, and simplicity in storage and separation. A number of investigations have shown that adding various medications and microRNAs to exosomes may enhance their therapeutic effectiveness. Thus, it is essential to evaluate studies looking into the therapeutic effectiveness of encapsulated exosomes. In this review, we looked at studies on encapsulated exosomes' use in regenerative medicine and the treatment of cancer. The results imply that the therapeutic potential increases when encapsulated exosomes are used rather than intact exosomes. Therefore, in order to optimize the effectiveness of the treatment, it is advised to implement this technique in accordance with the kind of therapy.

Toward the latest advancements in cardiac regeneration using induced pluripotent stem cells (iPSCs) technology: approaches and challenges

A novel approach to treating heart failures was developed with the introduction of iPSC technology. Knowledge in regenerative medicine, developmental biology, and the identification of illnesses at the cellular level has exploded since the discovery of iPSCs. One of the most frequent causes of mortality associated with cardiovascular disease is the loss of cardiomyocytes (CMs), followed by heart failure. A possible treatment for heart failure involves restoring cardiac function and replacing damaged tissue with healthy, regenerated CMs. Significant strides in stem cell biology during the last ten years have transformed the in vitro study of human illness and enhanced our knowledge of the molecular pathways underlying human disease, regenerative medicine, and drug development. We seek to examine iPSC advancements in disease modeling, drug discovery, iPSC-Based cell treatments, and purification methods in this article.

The role of the hematopoietic stem/progenitor cells-derived extracellular vesicles in hematopoiesis

Hematopoietic stem cells (HSCs) are tightly regulated by specific microenvironments called niches to produce an appropriate number of mature blood cell types. Self-renewal and differentiation are two hallmarks of hematopoietic stem and progenitor cells, and their balance is critical for proper functioning of blood and immune cells throughout life. In addition to cell-intrinsic regulation, extrinsic cues within the bone marrow niche and systemic factors also affect the fate of HSCs. Despite this, many paracrine and endocrine factors that influence the function of hematopoietic cells remain unknown. In hematological malignancies, malignant cells remodel their niche into a permissive environment to enhance the survival of leukemic cells. These events are accompanied by loss of normal hematopoiesis. It is well known that extracellular vehicles (EVs) mediate intracellular interactions under physiological and pathological conditions. In other words, EVs transfer biological information to surrounding cells and contribute not only to physiological functions but also to the pathogenesis of some diseases, such as cancers. Therefore, a better understanding of cell-to-cell interactions may lead to identification of potential therapeutic targets. Recent reports have suggested that EVs are evolutionarily conserved constitutive mediators that regulate hematopoiesis. Here, we focus on the emerging roles of EVs in normal and pathological conditions, particularly in hematological malignancies. Owing to the high abundance of EVs in biological fluids, their potential use as biomarkers and therapeutic tools is discussed.

Comparison of aquaporin profile of advanced passage mesenchymal stem cells with early passage mesenchymal stem cells and determination of its effect on adipogenic differentiation efficiency

OBJECTIVE

Our study aimed to compare aquaporin profiles in advanced and early passage bone marrow-derived mesenchymal stem cells (BM-MSCs) and assess the impact of aquaporin changes after adipogenic differentiation. Aquaporins are crucial for stem cell survival and differentiation during their life cycle. We focused on the role of aquaporins in the cell structures of advanced and early passage stem cells.

METHODS

In our study, BM-MSCs were used for our objectives. Characterization of the cells was evaluated via flow cytometry using stem cell surface markers. The characterized BM-MSCs were divided into control and differentiation groups at passages 3 (P3) and 8 (P8). AQP1, AQP3, AQP7, AQP9, and AQP10 expression levels on days 0, 1, 3, 7, 14, and 21 were evaluated using Real Time-PCR, ELISA, and immunofluorescence studies.

RESULTS

The cells were characterized by flow cytometry and confirmed to exhibit BM-MSC characteristics. At P3 and P8, differentiation was initiated, and AQP protein expression was observed to initially increase and then decrease on subsequent days. The increase in AQP protein expression at P3 occurred earlier than that at P8. Gene expression analysis demonstrated a statistically significant increase in AQP gene expression on days when AQP protein expression decreased. Moreover, statistical differences were observed between late and early passage AQP profiles.

CONCLUSION

Our study examined the composition of AQPs in BM-MSCs in association with cell passage, and found that AQPs play a role in the differentiation process. The connection between the AQP profile and aging might be related to differentiation capacity, which could have implications for slowing down cellular aging and developing new therapeutic approaches.

HypoxamiR-210-3p regulates mesenchymal stem cells proliferation via P53 & Akt

Transplanted stem cells (˃95%) into ischemic myocardium die because of unfavourable conditions. Moreover, hypoxia role in the cell cycle regulation has been studied in transformed/immortalized cell lines which may have altered cell cycle regulators and/or mutated and, can't be transplanted in patients. We quest to find out the mechanism of cell cycle regulation in mesenchymal stem cells (MSC) to regulate its survival and proliferation in repair processes. Additionally, critically analysed role of hypoxamiR-210-3p, and cell cycle regulators that can regulate cell proliferation under hypoxic conditions. Bone marrow-derived MSC (BM-MSC) isolated from young male Fischer-344 rats by flushing the cavity of femur and propagated in vitro under 1% hypoxia for 72 h showed an increased in cell proliferation ( > 30%, p < 0.05) compared to normoxia. miR-210-3p, role in cell proliferation under hypoxic condition was confirmed by knockdown. Loss of function studies with transfection of anti-mir-210-3p, we observed decrease in proliferation of BM-MSC under hypoxia. Furthermore, BM-MSC proliferation due to miR-210-3p was confirmed using CFSE assay and flow cytometry, in which more cells were observed in S-phase. Mechanistically, western blot analysis showed miR-210-3p inhibition upregulates p53 and p21 expression and subsequent decrease in pAkt under hypoxia. On contrary, CFSE and Western blot under normoxic conditions showed downregulation of p53 and p21 whilst upregulation of pAkt indicated the key role of miR-210-3p in BM-MSC proliferation. Our results demonstrate the role of miR-210-3p in BM-MSC proliferation under both hypoxic and normoxic conditions and illustrate the potential mechanism via the regulation of pAkt, p53 and p21.

RanGAP1 maintains chromosome stability in limb bud mesenchymal cells during bone development

BACKGROUND

Bone development involves the rapid proliferation and differentiation of osteogenic lineage cells, which makes accurate chromosomal segregation crucial for ensuring cell proliferation and maintaining chromosomal stability. However, the mechanism underlying the maintenance of chromosome stability during the rapid proliferation and differentiation of Prx1-expressing limb bud mesenchymal cells into osteoblastic precursor cells remains unexplored.

METHODS

A transgenic mouse model of RanGAP1 knockout of limb and head mesenchymal progenitor cells was constructed to explore the impact of RanGAP1 deletion on bone development by histomorphology and immunostaining. Subsequently, G-banding karyotyping analysis and immunofluorescence staining were used to examine the effects of RanGAP1 deficiency on chromosome instability. Finally, the effects of RanGAP1 deficiency on chromothripsis and bone development signaling pathways were elucidated by whole-genome sequencing, RNA-sequencing, and qPCR.

RESULTS

The ablation of RanGAP1 in limb and head mesenchymal progenitor cells expressing Prx1 in mice resulted in embryonic lethality, severe cartilage and bone dysplasia, and complete loss of cranial vault formation. Moreover, RanGAP1 loss inhibited chondrogenic or osteogenic differentiation of mesenchymal stem cells (MSCs). Most importantly, we found that RanGAP1 loss in limb bud mesenchymal cells triggered missegregation of chromosomes, resulting in chromothripsis of chromosomes 1q and 14q, further inhibiting the expression of key genes involved in multiple bone development signaling pathways such as WNT, Hedgehog, TGF-β/BMP, and PI3K/AKT in the chromothripsis regions, ultimately disrupting skeletal development.

CONCLUSIONS

Our results establish RanGAP1 as a critical regulator of bone development, as it supports this process by preserving chromosome stability in Prx1-expressing limb bud mesenchymal cells.

Alginate-gelatin hydrogel promotes the neurogenic differentiation potential of bone marrow CD117+ hematopoietic stem cells

People still hold the concept of using cell-based treatments to regenerate missing neurons in high esteem. CD117+ cells are considered favorable stem cells for regenerative medicine. The objective of this research was to examine the impact of Alginate-Gelatin (Alg-Gel) hydrogel on the process of neurogenic differentiation of CD117+ cells utilizing a cytokines secretion test conducted in a laboratory setting. To achieve this objective, bone marrow-CD117+ cells were isolated using the MACS technique and then transformed into neuron cells using a neurogenic differentiation medium. The characterization of enriched CD117+ cells has been done with flow cytometry as well as immunocytochemistry. Next, the cells underwent western blotting assay to evaluate the signaling pathways. Subsequently, the culture media was obtained from both groups in order to determine cytokine levels. The study revealed that the Alg-Gel hydrogel had a notable impact on enhancing the protein expression of neuron markers such as β-tubulin and Wnt/catenin signaling pathway components in CD117+ neurogenic differentiated cells. Furthermore, the cultured medium from the experimental group exhibited a notable abundance of IL-6 and IL-10 in comparison to the control group. The observed in vitro effects of Alg-Gel hydrogel on neurogenic differentiation of CD117+ cells are likely to be caused by the cytokines that are released.

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

Cytokines secreted from bone marrow-derived mesenchymal stem cells promote apoptosis of CD34+ leukemic stem cells as anti-cancer therapy

Objective

The effect of mesenchymal stem cells (MSCs) on the immortal characteristics of malignant cells, particularly hematologic cancer cells, remains a topic of debate, with the underlying mechanisms still requiring further elucidation. We explored the in vitro effect of the bone marrow-derived MSCs (BM-MSCs) on CD34+ leukemic stem cells (LSCs) enriched from the KG1-a cell line by assessing apoptosis, measuring cytokine levels, and examining TERT protein expression. Additionally, the potential signaling pathways implicated in this process, such as P53, PTEN, NF-κB, ERK1/2, Raf-1, and H-RAS, were also investigated.

Methods

CD34+ LSCs were enriched from the KG1-a cell line with the magnetic activated cell sorting (MACS) method. Two cell populations (BM-MSCs and CD34+ LSCs) were co-cultured on trans well plates for seven days. Next, CD34+ LSCs were collected and subjected to Annexin V/PI assay, cytokine measurement, and western blotting.

Results

BM-MSCs caused a significant increase in early and late apoptosis in the CD34+LSCs. The significant presence of interleukin (IL)-2 and IL-4 was evident in the co-cultured media. In addition, BM-MSCs significantly increased the protein expression of P53, PTEN, NF-κB, and significantly decreased p-ERK1/2, Raf-1, H-RAS, and TERT.

Conclusion

The mentioned effects of IL-2 and IL-4 cytokines released from BM-MSCs on CD34+ LSCs as therapeutic agents were applied by the components of P53, PTEN, NF-κB, p-ERK1/2, Raf-1, and H-RAS signaling pathways.

Silencing of forkhead box protein O-1 (FOXO-1) enhances insulin-producing cell generation from adipose mesenchymal stem cells for diabetes therapy

AIMS

Generation of mature β-cells from MSCs has been a challenge in the field of stem cell therapy of diabetes. Adipose tissue-derived mesenchymal stem cells (Ad-MSCs) have made their mark in regenerative medicine, and provide several advantages compared to other MSCs sources. Forkhead box protein O-1 (FOXO-1) is an important transcription factor for normal development of β-cells, yet its over expression in β-cells may cause glucose intolerance. In this study, we isolated, characterized Ad-MSCs from rat epididymal fat pads, differentiated these MSCs into insulin producing cells (IPCs) and studied the role of FOXO-1 in such differentiation.

MATERIALS AND METHODS

We examined the expression of FOXO-1 and its nuclear cytoplasmic localization in the generated IPCs. Afterwards we knocked down FOXO-1 using siRNA targeting FOXO-1 (siFOXO-1). The differentiated siFOXO-1 IPCs were compared to non-targeting siRNA (siNT) IPCs regarding expression of β-cell markers by qRT-PCR and western blotting, dithizone (DTZ) staining and glucose stimulated insulin secretion (GSIS).

KEY FINDINGS

Isolated Ad-MSCs exhibited all characteristics of MSCs and can generate IPCs. FOXO-1 was initially elevated during differentiation followed by a decline towards end of differentiation. FOXO-1 was dephosphorylated and localized to the nucleus upon differentiation into IPCs. Knock down of FOXO-1 improved the expression of β-cell markers in final differentiated IPCs, improved DTZ uptake and showed increased insulin secretion upon challenging with increased glucose concentration.

SIGNIFICANCE

These results portray FOXO-1 as a hindering factor of generation of IPCs whose down-regulation can generate more mature IPCs for MSCs therapy of diabetes mellitus.

Ginsenoside Rg1 promotes fetal hemoglobin production in vitro: A potential therapeutic avenue for β-thalassemia

β-thalassemia, a globally prevalent genetic disorder, urgently requires innovative treatment options. Fetal hemoglobin (HbF) induction stands as a key therapeutic approach. This investigation focused on Ginsenoside Rg1 from the Panax genus for HbF induction. Employing K562 cells and human erythroid precursor cells (ErPCs) derived from neonatal cord blood, the study tested Rg1 at different concentrations. We measured its effects on γ-globin mRNA levels and HbF expression, alongside assessments of cell proliferation and differentiation. In K562 cells, Rg1 at 400 μM significantly increased γ-globin mRNA expression by 4.24 ± 1.08-fold compared to the control. In ErPCs, the 800 μM concentration was most effective, leading to an over 80% increase in F-cells and a marked upregulation in HbF expression. Notably, Rg1 did not adversely affect cell proliferation or differentiation, with the 200 μM concentration showing an increase in γ-globin mRNA by 2.33 ± 0.58-fold, and the 800 μM concentration enhancing HbF expression by 2.59 ± 0.03-fold in K562 cells. Our results underscore Rg1's potential as an effective and safer alternative for β-thalassemia treatment. By significantly enhancing HbF levels without cytotoxicity, Rg1 offers a notable advantage over traditional treatments like Hydroxyurea. While promising, these in vitro findings warrant further in vivo exploration to confirm Rg1's therapeutic efficacy and to unravel its underlying mechanistic pathways.

Bone marrow mesenchymal stem cells suppress activated CD4+ T cells proliferation through TGF-beta and IL10 dependent of autophagy in pathological hypoxic microenvironment

BACKGROUND

Bone marrow mesenchymal stem cells (BMSCs) mediated immunomodulation by secreting certain bioactive cytokines has been recognized as a promising approach for disease treatment. However, microenvironmental oxygen tension affect immunomodulatory functions and activate autophagy in BMSCs. The mechanism governing BMSCs immunomodulation in hypoxia hasn't been expounded clearly. The aim of this study is to investigate the function of pathological hypoxia on immunomodulatory properties of bone marrow mesenchymal stem cells and its possible mechanism.

METHODS

BMSCs were cultured in either normoxia (21 % oxygen) or hypoxia (0.1 % oxygen) for 24 h, then electron microscopy (EM) and immunofluorescence staining were used to detect the activation of autophagy. Besides autophagy-related markers were monitored by Western blotting. Atg5 siRNA induced autophagic inhibition. Additional, gene expression levels of Real-time fluorescence quantitative PCR and Western blot were used to detect BMSCs related cytokines. Both the proliferation and apoptosis of CD4+ T cell in co-culture were detected by flow cytometry. Exogenous anti-IL-10 antibody and anti-TGF-β1 antibody were used in co-cultured BMSCs-CM and CD4+ T cells, which enabled us to assess how autophagy affected BMSCs-mediated CD4+ T cell proliferation in low oxygen tension.

RESULT

Compared with normal BMSCs, Hypo-BMSCs enhanced the immunosuppressive effect of BMSCs on CD4+ T cell proliferation, while si-atg5 weakened the inhibition of Hypo-BMSCs. Furthermore, exogenous anti-TGF-β1 antibody and the addition of anti-TGF-β1 antibody reversed the immunosuppressive ability of Hypo-BMSCs.

CONCLUSIONS

Our findings reveal that BMSCs possess significant immunosuppression on CD4+T cell through IL-10 and TGF-β1 dependent of autophagy in hypoxic microenvironment.

Stem cells as a regenerative medicine approach in treatment of microvascular diabetic complications

Diabetes mellitus (DM) is a chronic metabolic disorder characterized by high blood glucose and is associated with high morbidity and mortality among the diabetic population. Uncontrolled chronic hyperglycaemia causes increased formation and accumulation of different oxidative and nitrosative stress markers, resulting in microvascular and macrovascular complications, which might seriously affect the quality of a patient's life. Conventional treatment strategies are confined to controlling blood glucose by regulating the insulin level and are not involved in attenuating the life-threatening complications of diabetes mellitus. Thus, there is an unmet need to develop a viable treatment strategy that could target the multi-etiological factors involved in the pathogenesis of diabetic complications. Stem cell therapy, a regenerative medicine approach, has been investigated in diabetic complications owing to their unique characteristic features of self-renewal, multilineage differentiation and regeneration potential. The present review is focused on potential therapeutic applications of stem cells in the treatment of microvascular diabetic complications such as nephropathy, retinopathy, and polyneuropathy.

Granulocyte differentiation of rat bone marrow resident C-kit+ hematopoietic stem cells induced by mesenchymal stem cells could be considered as new option in cell-based therapy

Mesenchymal stem cells (MSCs) are effective in hematopoietic engraftment and tissue repair in stem cell transplantation. In addition, these cells control the process of hematopoiesis by secreting growth factors and cytokines. The aim of the present study is to investigate the effect of rat bone marrow (BM)-derived MSCs on the granulocyte differentiation of rat BM-resident C-kit+ hematopoietic stem cells (HSCs). The mononuclear cells were collected from rat BM using density gradient centrifugation and MSCs and C-kit+ HSCs were isolated. Then, cells were divided into two groups and differentiated into granulocytes; C-kit+ HSCs alone (control group) and co-cultured C-kit+ HSCs with MSCs (experimental group). Subsequently, the granulocyte-differentiated cells were collected and subjected to real-time PCR and Western blotting for the assessment of their telomere length (TL) and protein expressions, respectively. Afterwards, culture medium was collected to measure cytokine levels. CD34, CD16, CD11b, and CD18 granulocyte markers expression levels were significantly increased in the experimental group compared to the control group. A significant change was also observed in the protein expression of Wnt and β-catenin. In addition, MSCs caused an increase in the TL of granulocyte-differentiated cells. MSCs could affect the granulocyte differentiation of C-kit+ HSCs via increasing TL and Wnt/β-catenin protein expression.

In vitro erythrocyte production using human-induced pluripotent stem cells: determining the best hematopoietic stem cell sources

BACKGROUND

Blood transfusion is an essential part of medicine. However, many countries have been facing a national blood crisis. To address this ongoing blood shortage issue, there have been efforts to generate red blood cells (RBCs) in vitro, especially from human-induced pluripotent stem cells (hiPSCs). However, the best source of hiPSCs for this purpose is yet to be determined.

METHODS

In this study, hiPSCs were established from three different hematopoietic stem cell sources-peripheral blood (PB), cord blood (CB) and bone marrow (BM) aspirates (n = 3 for each source)-using episomal reprogramming vectors and differentiated into functional RBCs. Various time-course studies including immunofluorescence assay, quantitative real-time PCR, flow cytometry, karyotyping, morphological analysis, oxygen binding capacity analysis, and RNA sequencing were performed to examine and compare the characteristics of hiPSCs and hiPSC-differentiated erythroid cells.

RESULTS

hiPSC lines were established from each of the three sources and were found to be pluripotent and have comparable characteristics. All hiPSCs differentiated into erythroid cells, but there were discrepancies in differentiation and maturation efficiencies: CB-derived hiPSCs matured into erythroid cells the fastest while PB-derived hiPSCs required a longer time for maturation but showed the highest degree of reproducibility. BM-derived hiPSCs gave rise to diverse types of cells and exhibited poor differentiation efficiency. Nonetheless, erythroid cells differentiated from all hiPSC lines mainly expressed fetal and/or embryonic hemoglobin, indicating that primitive erythropoiesis occurred. Their oxygen equilibrium curves were all left-shifted.

CONCLUSIONS

Collectively, both PB- and CB-derived hiPSCs were favorably reliable sources for the clinical production of RBCs in vitro, despite several challenges that need to be overcome. However, owing to the limited availability and the large amount of CB required to produce hiPSCs, and the results of this study, the advantages of using PB-derived hiPSCs for RBC production in vitro may outweigh those of using CB-derived hiPSCs. We believe that our findings will facilitate the selection of optimal hiPSC lines for RBC production in vitro in the near future.

The effects of encapsulation on NK cell differentiation potency of C-kit+ hematopoietic stem cells via identifying cytokine profiles

Natural killer cells (NK cells) can kill cancerous cells without prior sensitization. This feature makes them appealing candidates for cellular therapy. Due to the degradation rate and controlled release of these matrices, hydrogels hold great promise in cell differentiation. The study aims to investigate the effect of encapsulated alginate-gelatin on the differentiation potential of C-kit⁺ cells toward NK cells which are mediated by cytokines detection. Under both encapsulated and unencapsulated conditions, C-kit⁺ cells can differentiate into NK cells. In the following, real-time PCR and western blotting were done to investigate the mRNA and protein expression, respectively. Determine cytokine profiles from the collected culture medium conducted a Cytokine antibody array. The differentiated cells were then co-cultured with Molt-4 cells to examine the expression levels of INF-γ, TNF-α, and IL-10 using real-time-PCR. There was a substantial change in protein expression of the Notch pathway. Also, the encapsulation increased the mRNA expression of INF-γ and TNF-α in Molt-4 cells. Based on these findings, the encapsulation effects on the differentiation of C-kit⁺ cells toward NK cells could be related to the secreted cytokines such as interleukin-10 and INF-γ and the Notch protein expression.

Bone Marrow-Derived Vasculogenic Mesenchymal Stem Cells Enhance In Vitro Angiogenic Sprouting of Human Umbilical Vein Endothelial Cells

Vasculogenic properties of bone marrow-derived mesenchymal stem cells (MSCs) have been reported, but it is still unclear whether the vasculogenic properties are restricted to some populations of MSCs or whether the entire population of MSCs has these properties. We cultured two different populations of MSCs in different culture media and their vasculogenic properties were evaluated using In vitro spheroid sprouting assay. Neither population of MSCs expressed markers of endothelial progenitor cells (EPCs), but they were different in the profiling of angiogenic factor expression as well as vasculogenic properties. One population of MSCs expressed basic fibroblast growth factor (bFGF) and another expressed hepatocyte growth factor (HGF). MSCs expressing HGF exhibited In vitro angiogenic sprouting capacity in response to bFGF derived from other MSCs as well as to their autocrine HGF. The vasculogenic mesenchymal stem cells (vMSCs) derived from the bone marrow also enhanced In vitro angiogenic sprouting capacity of human umbilical vein endothelial cells (HUVECs) in an HGF-dependent manner. These results suggest that MSCs exhibit different vasculogenic properties, and vMSCs that are different from EPCs may contribute to neovascularization and could be a promising cellular therapy for cardiovascular diseases.