In vitro protection of adipose tissue-derived mesenchymal stem cells by erythropoietin

Dual role of quercetin in enhancing the efficacy of cisplatin in chemotherapy and protection against its side effects: a review

Chemotherapy has opened a new window in cancer therapy. However, the resistance of cancer cells has dramatically reduced the efficacy of chemotherapy. Cisplatin is a chemotherapeutic agent and its potential in cancer therapy has been restricted by resistance of cancer cells. As a consequence, the scientists have attempted to find new strategies in elevating chemotherapy efficacy. Due to great anti-tumour activity, naturally occurring compounds are of interest in polychemotherapy. Quercetin is a flavonoid with high anti-tumour activity against different cancers that can be used with cisplatin to enhance its efficacy and also are seen to sensitise cancer cells into chemotherapy. Furthermore, cisplatin has side effects such as nephrotoxicity and ototoxicity. Administration of quercetin is advantageous in reducing the adverse effects of cisplatin without compromising its anti-tumour activity. In this review, we investigate the dual role of quercetin in enhancing anti-tumour activity of cisplatin and simultaneous reduction in its adverse effects.

Transplanted Erythropoietin-Expressing Mesenchymal Stem Cells Promote Pro-survival Gene Expression and Protect Photoreceptors From Sodium Iodate-Induced Cytotoxicity in a Retinal Degeneration Model

Mesenchymal stem cells (MSC) are highly regarded as a potential treatment for retinal degenerative disorders like retinitis pigmentosa and age-related macular degeneration. However, donor cell heterogeneity and inconsistent protocols for transplantation have led to varied outcomes in clinical trials. We previously showed that genetically-modifying MSCs to express erythropoietin (MSC^EPO) improved its regenerative capabilities in vitro. Hence, in this study, we sought to prove its potential in vivo by transplanting MSCs^EPO in a rat retinal degeneration model and analyzing its retinal transcriptome using RNA-Seq. Firstly, MSCs^EPO were cultured and expanded before being intravitreally transplanted into the sodium iodate-induced model. After the procedure, electroretinography (ERG) was performed bi-weekly for 30 days. Histological analyses were performed after the ERG assessment. The retina was then harvested for RNA extraction. After mRNA-enrichment and library preparation, paired-end RNA-Seq was performed. Salmon and DESeq2 were used to process the output files. The generated dataset was then analyzed using over-representation (ORA), functional enrichment (GSEA), and pathway topology analysis tools (SPIA) to identify enrichment of key pathways in the experimental groups. The results showed that the MSC^EPO-treated group had detectable ERG waves (P <0.05), which were indicative of successful phototransduction. The stem cells were also successfully detected by immunohistochemistry 30 days after intravitreal transplantation. An initial over-representation analysis revealed a snapshot of immune-related pathways in all the groups but was mainly overexpressed in the MSC group. A subsequent GSEA and SPIA analysis later revealed enrichment in a large number of biological processes including phototransduction, regeneration, and cell death (P_adj <0.05). Based on these pathways, a set of pro-survival gene expressions were extracted and tabulated. This study provided an in-depth transcriptomic analysis on the MSC^EPO-treated retinal degeneration model as well as a profile of pro-survival genes that can be used as candidates for further genetic enhancement studies on stem cells.

Therapeutic effects of erythropoietin expressed in mesenchymal stem cells for dilated cardiomyopathy in rat

Dilated cardiomyopathy (DCM) is considered as the final common response of myocardium to diverse genetic and environmental insults and characterized mainly by left ventricular systolic dysfunction. The current therapies for the treatment of DCM are costly high and outcomes are often unsatisfactory. To date, mesenchymal stem cells (MSCs) have been thought to be an ideal stem cell to repair damaged myocardium but was still within relatively small scales and few cases have been conducted in clinical trials. The use of erythropoietin (EPO), a growth factor produced in the kidneys have been found prevent cardiomyocyte apoptosis. This study was aimed to transplant MSCs into DCM rat bone marrow to express EPO in vivo and investigate the regulation of EPO on cell signaling pathways after transfection. The results found that transplantation of MSCs carrying EPO could significantly relief the cardiac dysfunctions of the DCM rat. This underylying mechanism involved with inhibiting p-NF-κB and p-P38, regulateing and promoting the anti-inflammatory balance, thereby alleviating tissue injury in DCM rats and exhibiting a protective role. Meanwhile, the MSCs + EPO treatment in DCM rat also activated the p-Akt pathway and thus protecting the myocardium from apoptosis in DCM rats. The study revealed an potential therapeutic effect of MSCs and EPO in clinical and provided a molecular mechanism of action for treating DCM.

Pharmacological modulation of cell functional activity with valproic acid and erythropoietin

Introduction: Valproic acid (VA) is carboxylic acid with a branched chain, which is used as an antiepileptic drug.

Valproic acid influence on cells in vivo: VA, which is an antiepileptic drug, is also a teratogen, which causes defects of a neural tube and an axial skeleton, although the mechanisms are not yet fully clear.

Valproic acid influence on mesenchymal stem cells (MSC) in vitro: It is shown that valproic acid reduces the intracellular level of oxygen active forms.

Valproic acid effect on tumor cells: VA inhibits tumor growth through several mechanisms, including the cell cycle stop, differentiation induction and inhibition of growth of tumor vessels.

Valproic acid influence on enzymes: It affects mainly GSK-3.

Valproic acid influence on animals’ cells: It is shown that VA can significantly improve an ability to develop in vitro and improve nuclear reprogramming of embryos.

Erythropoietin (EPO): Is an hypoxia-induced hormone and a cytokine, which is necessary for normal erythropoiesis. EPO is widely used in in vitro experiments.

Conclusion: Thus, the influence of VA and EPO on cells can be used in cell technologies.

Modification of Bone Marrow Stem Cells for Homing and Survival During Cerebral Ischemia

Over the last decade, major advances have been made in stem cell-based therapy for ischemic stroke, which is one of the leading causes of death and disability worldwide. Various stem cells from bone marrow, such as mesenchymal stem cells (MSCs), hematopoietic stem cells (HSCs), and endothelial progenitor cells (EPCs), have shown therapeutic potential for stroke. Concomitant with these exciting findings are some fundamental bottlenecks that must be overcome in order to accelerate their clinical translation, including the low survival and engraftment caused by the harsh microenvironment after transplantation. In this chapter, strategies such as gene modification, hypoxia/growth factor preconditioning, and biomaterial-based methods to improve cell survival and homing are summarized, and the potential strategies for their future application are also discussed.

Effects of CoCl2 on multi-lineage differentiation of C3H/10T1/2 mesenchymal stem cells

Mesenchymal stem cells (MSCs) in the bone marrow and other somatic tissues reside in an environment with relative low oxygen tension. Cobalt chloride (CoCl₂) can mimic hypoxic conditions through transcriptional changes of some genes including hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). This study evaluated the potential role of CoCl₂ preconditioning on multi-lineage differentiation of C3H/10T1/2, a murine MSC line to understand its possible molecular mechanisms in vitro. CoCl₂ treatment of MSCs markedly increased HIF-1α and VEGF mRNA, and protein expression of HIF-1α. Temporary preconditioning of MSCs with CoCl₂ induced up-regulation of osteogenic markers including alkaline phosphatase, osteocalcin, and type I collagen during osteogenic differentiation, followed by enhanced mineralization. CoCl₂ also increased chondrogenic markers including aggrecan, sox9, and type II collagen, and promoted chondrocyte differentiation. CoCl₂ suppressed the expression of adipogenic markers including PPARγ, aP2, and C/EBPα, and inhibited adipogenesis. Temporary preconditioning with CoCl₂ could affect the multi-lineage differentiation of MSCs.

Transplantation of erythropoietin gene-modified neural stem cells improves the repair of injured spinal cord

The protective effects of erythropoietin on spinal cord injury have not been well described. Here, the eukaryotic expression plasmid pcDNA3.1 human erythropoietin was transfected into rat neural stem cells cultured in vitro. A rat model of spinal cord injury was established using a free falling object. In the human erythropoietin-neural stem cells group, transfected neural stem cells were injected into the rat subarachnoid cavity, while the neural stem cells group was injected with non-transfected neural stem cells. Dulbecco's modified Eagle's medium/F12 medium was injected into the rats in the spinal cord injury group as a control. At 1–4 weeks post injury, the motor function in the rat lower limbs was best in the human erythropoietin-neural stem cells group, followed by the neural stem cells group, and lastly the spinal cord injury group. At 72 hours, compared with the spinal cord injury group, the apoptotic index and Caspase-3 gene and protein expressions were apparently decreased, and the bcl-2 gene and protein expressions were noticeably increased, in the tissues surrounding the injured region in the human erythropoietin-neural stem cells group. At 4 weeks, the cavities were clearly smaller and the motor and somatosensory evoked potential latencies were remarkably shorter in the human erythropoietin-neural stem cells group and neural stem cells group than those in the spinal cord injury group. These differences were particularly obvious in the human erythropoietin-neural stem cells group. More CM-Dil-positive cells and horseradish peroxidase-positive nerve fibers and larger amplitude motor and somatosensory evoked potentials were found in the human erythropoietin-neural stem cells group and neural stem cells group than in the spinal cord injury group. Again, these differences were particularly obvious in the human erythropoietin-neural stem cells group. These data indicate that transplantation of erythropoietin gene-modified neural stem cells into the subarachnoid cavity to help repair spinal cord injury and promote the recovery of spinal cord function better than neural stem cell transplantation alone. These findings may lead to significant improvements in the clinical treatment of spinal cord injuries.