The effect of ketorolac and triamcinolone acetonide on adipogenic and hepatogenic differentiation through miRNAs 16/15/195: Possible clinical application in regenerative medicine

7-Ketocholesterol Effects on Osteogenic Differentiation of Adipose Tissue-Derived Mesenchymal Stem Cells

Some oxysterols were shown to promote osteogenic differentiation of mesenchymal stem cells (MSCs). Little is known about the effects of 7-ketocholesterol (7-KC) in this process. We describe its impact on human adipose tissue-derived MSC (ATMSC) osteogenic differentiation. ATMSCs were incubated with 7-KC in osteogenic or adipogenic media. Osteogenic and adipogenic differentiation was evaluated by Alizarin red and Oil Red O staining, respectively. Osteogenic (ALPL, RUNX2, BGLAP) and adipogenic markers (PPARƔ, C/EBPα) were determined by RT-PCR. Differentiation signaling pathways (SHh, Smo, Gli-3, β-catenin) were determined by indirect immunofluorescence. ATMSCs treated with 7-KC in osteogenic media stained positively for Alizarin Red. 7-KC in adipogenic media decreased the number of adipocytes. 7-KC increased ALPL and RUNX2 but not BGLAP expressions. 7-KC decreased expression of PPARƔ and C/EBPα, did not change SHh, Smo, and Gli-3 expression, and increased the expression of β-catenin. In conclusion, 7-KC favors osteogenic differentiation of ATMSCs through the expression of early osteogenic genes (matrix maturation phase) by activating the Wnt/β-catenin signaling pathway, while inhibiting adipogenic differentiation. This knowledge can be potentially useful in regenerative medicine, in treatments for bone diseases.

Triple-layered scaffold containing cisplatin and curcumin applied for cancerous bone regeneration

Novel drug delivery system was prepared and evaluated as for application in cancerous bone treatment. It had three stacked layers, including a drug-free layer, a cisplatin-loaded layer, and a curcumin-containing layer. Our previously characterized biomaterials, namely Zr-hydroxyapatite (Zr-HA) and alkaline-treated polycaprolactone (modified-PCL), were used as major components of the drug carrier. Polar-polar interactions between cisplatin and Zr-HA were modulated by the modified-PCL included, leading to increase of cisplatin release. Using β-cyclodextrin (β-CD) to entrap curcumin caused improvement of curcumin solubility and release. The 3D-construct was porous with internal interconnected pores according to SEM micrographs. Large amount of apatite was formed and proteins adsorbed on the scaffolds after immersed in physiologic buffer solution and in medium containing fetal bovine serum, respectively. Optimal concentrations of ascorbic acid and triamcinolone were used for induction of bone marrow stromal cells to become osteoblasts by expressing an enzyme marker, e.g., alkaline phosphatase. The prepared scaffolds were considered osteo-conductive and osteo-inductive. The concentrations of cisplatin and curcumin reached the IC50 of SK-ES-1 cells of osteosarcoma and MCF-7 cells of breast adenocarcinoma after 24 h and 3 days of release, respectively. These cancer cells were more sensitive to the combined cisplatin and curcumin than each of the drugs. Regeneration of new bone and execution of residential cancer cells in defected bone were proposed after replacing the lost bone by this established drug carrier. The assumption needs to be verified in the future using animal models.

Sodium selenite preserves rBM-MSCs' stemness, differentiation potential, and immunophenotype and protects them against oxidative stress via activation of the Nrf2 signaling pathway

BACKGROUND

The physiological level of reactive oxygen species (ROS) is necessary for many cellular functions. However, during the in-vitro manipulations, cells face a high level of ROS, leading to reduced cell quality. Preventing this abnormal ROS level is a challenging task. Hence, here we evaluated the effect of sodium selenite supplementation on the antioxidant potential, stemness capacity, and differentiation of rat-derived Bone Marrow MSCs (rBM-MSCs) and planned to check our hypothesis on the molecular pathways and networks linked to sodium selenite's antioxidant properties.

METHODS

MTT assay was used to assess the rBM-MSCs cells' viability following sodium selenite supplementation (concentrations of: 0.001, 0.01, 0.1, 1, 10 µM). The expression level of OCT-4, NANOG, and SIRT1 was explored using qPCR. The adipocyte differentiation capacity of MSCs was checked after Sodium Selenite treatment. The DCFH-DA assay was used to determine intracellular ROS levels. Sodium selenite-related expression of HIF-1α, GPX, SOD, TrxR, p-AKT, Nrf2, and p38 markers was determined using western blot. Significant findings were investigated by the String tool to picture the probable molecular network.

RESULTS

Media supplemented with 0.1 µM sodium selenite helped to preserve rBM-MSCs multipotency and keep their surface markers presentation; this also reduced the ROS level and improved the rBM-MSCs' antioxidant and stemness capacity. We observed enhanced viability and reduced senescence for rBM-MSCs. Moreover, sodium selenite helped in rBM-MSCs cytoprotection by regulating the expression of HIF-1 of AKT, Nrf2, SOD, GPX, and TrxR markers.

CONCLUSIONS

We showed that sodium selenite could help protect MSCs during in-vitro manipulations, probably via the Nrf2 pathway.

Long noncoding RNA SNHG1 silencing accelerates hepatocyte-like cell differentiation of bone marrow-derived mesenchymal stem cells to alleviate cirrhosis via the microRNA-15a/SMURF1/UVRAG axis

Bone marrow-derived mesenchymal stem cells (BMSCs) can differentiate into hepatocyte-like cells (HLCs) to attenuate cirrhosis. Long noncoding RNA (lncRNA) SNHG1 has been demonstrated to orchestrate BMSC differentiation, whereas its role in cirrhosis remains elusive. Therefore, this study was performed to figure out whether lncRNA SNHG1 was involved in cirrhosis by affecting HLC differentiation of BMSCs. Mouse BMSCs were isolated, and the BMSC differentiation into HLCs was induced by hepatocyte growth factor (HGF). A cirrhotic mouse model was established using carbon tetrachloride and phenobarbital, followed by intravenous injection of BMSCs with manipulated expression of lncRNA SNHG1, microRNA (miR)-15a, and SMURF1. Subsequent to HGF induction, expression of hepatocyte-related genes, albumin secretion, and glycogen accumulation was increased in BMSCs, suggesting the differentiation of BMSCs into HLCs. Mechanistically, lncRNA SNHG1 bound to miR-15a that targeted SMURF1, and SMURF1 diminished ATG5 and Wnt5a expression by enhancing the ubiquitination of UVRAG. LncRNA SNHG1 or SMURF1 silencing or miR-15a overexpression promoted differentiation of BMSCs into HLCs and repressed cirrhosis of mice by upregulating ATG5 and Wnt5a via UVRAG. Conclusively, lncRNA SNHG1 silencing might facilitate HLC differentiation from mouse BMSCs and alleviate cirrhosis via the miR-15a/SMURF1/UVRAG/ATG5/Wnt5a axis.

The cross-talk between adipokines and miRNAs in health and obesity-mediated diseases

BACKGROUND

Multiple studies have revealed a direct correlation between obesity and the development of multiple comorbidities, including metabolic diseases, cardiovascular disorders, chronic inflammatory disease, and cancers. However, the molecular mechanism underlying the link between obesity and the progression of these diseases is not completely understood. Adipokines are factors that are secreted by adipocytes and play a key role in whole body homeostasis. Collaboratively, miRNAs are suggested to have key functions in the development of obesity and obesity-related disorders. Based on recently emerging evidence, obesity leads to the dysregulation of both adipokines and obesity-related miRNAs. In the present study, we described the correlations between obesity and its related diseases that are mediated by the mutual regulatory effects of adipokines and miRNAs.

METHODS

We reviewed current knowledge of the modulatory effects of adipokines on miRNAs activity and their relevant functions in pathological conditions and vice versa.

RESULTS

Our research reveals the ability of adipokines and miRNAs to control the expression and activity of the other class of molecules, and their effects on obesity-related diseases.

CONCLUSIONS

This study may help researchers develop a roadmap for future investigations and provide opportunities to develop new therapeutic and diagnostic methods for treating obesity-related diseases.

Systemic Dysfunction of Osteoblast Differentiation in Adipose-Derived Stem Cells from Patients with Multiple Myeloma

Multiple myeloma is characterized by bone lesions linked to increased osteoclast and decreased osteoblast activities. In particular, the osteoblast differentiation of bone marrow-derived stem cells (MSC) is impaired. Among the potential therapeutic tools for counteracting bone lesions, adipose-derived stem cells (ASC) could represent an appealing source for regenerative medicine due to their similar characteristics with MSC. Our study is among the first giving detailed insights into the osteoblastogenic capacities of ASC isolated by fat aspiration from myeloma patients (MM-ASC) compared to healthy subjects (HD-ASC). We showed that MM-ASC and HD-ASC exhibited comparable morphology, proliferative capacity, and immunophenotype. Unexpectedly, although normal in adipocyte differentiation, MM-ASC present a defective osteoblast differentiation, as indicated by less calcium deposition, decreased alkaline phosphatase activity, and downregulation of RUNX2 and osteocalcin. Furthermore, these ASC-derived osteoblasts displayed enhanced senescence, as shown by an increased β-galactosidase activity and cell cycle inhibitors expression (p16^INK4A, p21^WAF1/CIP1.), associated with a markedly increased expression of DKK1, a major inhibitor of osteoblastogenesis in multiple myeloma. Interestingly, inhibition of DKK1 attenuated senescence and rescued osteoblast differentiation, highlighting its key role. Our findings show, for the first time, that multiple myeloma is a systemic disease and suggest that ASC from patients would be unsuitable for tissue engineering designed to treat myeloma-associated bone disease.

MiR-15/16 mediate crosstalk between the MAPK and Wnt/β-catenin pathways during hepatocyte differentiation from amniotic epithelial cells

MiR-15/16 play an important role in liver development and hepatocyte differentiation, but the mechanisms by which these miRNAs regulate their targets and downstream genes to influence cell fate are poorly understood. In this study, we showed up-regulation of miR-15/16 during HGF- and FGF4-induced hepatocyte differentiation from amniotic epithelial cells (AECs). To elucidate the role of miR-15/16 and their targets in hepatocyte differentiation, we investigated the roles of miR-15/16 in both the MAPK and Wnt/β-catenin pathways, which were predicted to be involved in miR-15/16 signaling. Our results demonstrated that the transcription of miR-15/16 was enhanced by c-Fos, c-Jun, and CREB, important elements of the MAPK pathway, and miR-15/16 in turn directly targeted adenomatous polyposis coli (APC) protein, a major member of the β-catenin degradation complex. MiR-15/16 destroyed these degradation complexes to activate β-catenin, and the activated β-catenin combined with LEF/TCF7L1 to form a transcriptional complex that enhanced transcription of hepatocyte nuclear factor 4 alpha (HNF4α). HNF4α also bound the promoter region of miR-15/16 and promoted its transcription, thereby forming a regulatory circuit to promote the differentiation of AECs into hepatocytes. Endogenous miRNAs are, therefore, involved in hepatocyte differentiation from AECs and should be considered during the development of an effective hepatocyte transplant therapy for liver damage.

Induced pluripotent stem cell-derived extracellular vesicles: A novel approach for cell-free regenerative medicine

In recent years, induced pluripotent stem cells (iPSCs) have been considered as a promising approach in the field of regenerative medicine. iPSCs can be generated from patients' somatic cells and possess the potential to differentiate, under proper conditions, into any cell type. However, the clinical application of iPS cells is restricted because of their tumorigenic potential. Recent studies have indicated that stem cells exert their therapeutic benefit via a paracrine mechanism, and extracellular vesicles have been demonstrated that play a critical role in this paracrine mechanism. Due to lower immunogenicity, easier management, and presenting no risk of tumor formation, in recent years, researchers turned attention to exosomes as potential alternatives to whole-cell therapy. Application of exosomes derived from iPSCs and their derived precursor provides a promising approach for personalized regenerative medicine. This study reviews the physiological functions of extracellular vesicles and discusses their potential therapeutic benefit in regenerative medicine.

Epigenetics and Epi-miRNAs: Potential markers/therapeutics in leukemia

Epigenetic variations can play remarkable roles in different normal and abnormal situations. Such variations have been shown to have a direct role in the pathogenesis of various diseases either through inhibition of tumor suppressor genes or increasing the expression of oncogenes. Enzymes involving in epigenetic machinery are the main actors in tuning the epigenetic-based controls on gene expressions. Aberrant expression of these enzymes can trigger a big chaos in the cellular gene expression networks and finally lead to cancer progression. This situation has been shown in different types of leukemia, where high or low levels of an epigenetic enzyme are partly or highly responsible for involvement or progression of a disease. DNA hypermethylation, different histone modifications, and aberrant miRNA expressions are three main epigenetic variations, which have been shown to play a role in leukemia progression. Epigenetic based treatments now are considered as novel and effective therapies in order to decrease the abnormal epigenetic modifications in patient cells. Different epigenetic-based approaches have been developed and tested to inhibit or reverse the unusual expression of epigenetic agents in leukemia. The reciprocal behavior of miRNAs in the regulation of epigenetic modifiers, while being regulated by them, unlocks a new opportunity in order to design some epigenetic-based miRNAs able to silence or sensitize these effectors in leukemia.