Human amnion-derived mesenchymal stem cells promote osteogenic and angiogenic differentiation of human adipose-derived stem cells

Osteogenic Differentiation Effect of BMP-9 with Phenamil and Simvastatin on Intact Human Amniotic Epithelial Stem Cells

Background

Background: Bone tissue engineering has shown to be a promising strategy for repairing bone defects without causing harmful side effects to the patient. Three main building blocks of tissue engineering, including seeding cells, scaffold, and signaling molecules, are required for adequate bone regeneration. The human amniotic membrane (hAM) is the innermost of the placental membranes. In addition to providing a source of stem cells and growth factors, hAM has several features that make it an appropriate scaffold containing stem cells for use in tissue engineering purposes. The present investigation aimed to assess the effect of bone morphogenetic protein-9 (BMP-9) combined with phenamil and simvastatin on osteogenic induction of hAM with its human amniotic membrane epithelial cells (hAECs).

Method

Methods: Using six different osteogenic medium (OMs), we cultured hAM for 14 days. The basic OMs were chosen as the first group and other media were made by adding BMP-9, phenamil, simvastatin, BMP-9 alongside phenamil, and BMP-9 alongside simvastatin to the basic OMs. Finally, viability assay, tissue mineralization, calcium and phosphate content determination, and measurement of lactic acid dehydrogenase (LDH), and alkaline phosphatase (ALP) activity were performed.

Results

Results: Among all study groups, groups containing simvastatin showed a significantly lower level of viability. Although all media could induce osteogenic features, the hAECs cultured in media containing BMP-9 and phenamil demonstrated a wider area of mineralization and a significantly higher level of calcium and phosphate content, LDH, and ALP activity.

Conclusion

Conclusion: Our findings indicated that the use of phenamil together with BMP-9 could synergistically show in situ osteogenic induction in hAECs, which could be a new insight into translational medicine.

The angiogenic properties of human amniotic membrane stem cells are enhanced in gestational diabetes and associate with fetal adiposity

Background

An environment of gestational diabetes mellitus (GDM) can modify the phenotype of stem cell populations differentially according to their placental localization, which can be useful to study the consequences for the fetus. We sought to explore the effect of intrauterine GDM exposure on the angiogenic properties of human amniotic membrane stem cells (hAMSCs).

Methods

We comprehensively characterized the angiogenic phenotype of hAMSCs isolated from 14 patients with GDM and 14 controls with normal glucose tolerance (NGT). Maternal and fetal parameters were also recorded. Hyperglycemia, hyperinsulinemia and palmitic acid were used to in vitro mimic a GDM-like pathology. Pharmacological and genetic inhibition of protein function was used to investigate the molecular pathways underlying the angiogenic properties of hAMSCs isolated from women with GDM.

Results

Capillary tube formation assays revealed that GDM-hAMSCs produced a significantly higher number of nodes (P = 0.004), junctions (P = 0.002) and meshes (P < 0.001) than equivalent NGT-hAMSCs, concomitant with an increase in the gene/protein expression of FGFR2, TGFBR1, SERPINE1 and VEGFA. These latter changes were recapitulated in NGT-hAMSCs exposed to GDM-like conditions. Inhibition of the protein product of SERPINE1 (plasminogen activator inhibitor 1, PAI-1) suppressed the angiogenic properties of GDM-hAMSCs. Correlation analyses revealed that cord blood insulin levels in offspring strongly correlated with the number of nodes (r = 0.860; P = 0.001), junctions (r = 0.853; P = 0.002) and meshes (r = 0.816; P = 0.004) in tube formation assays. Finally, FGFR2 levels correlated positively with placental weight (r = 0.586; P = 0.028) and neonatal adiposity (r = 0.496; P = 0.014).

Conclusions

GDM exposure contributes to the angiogenic abilities of hAMSCs, which are further related to increased cord blood insulin and fetal adiposity. PAI-1 emerges as a potential key player of GDM-induced angiogenesis.

Stem/progenitor cells in fetuses and newborns: overview of immunohistochemical markers

Microanatomy of the vast majority of human organs at birth is characterized by marked differences as compared to adult organs, regarding their architecture and the cell types detectable at histology. In preterm neonates, these differences are even more evident, due to the lower level of organ maturation and to ongoing cell differentiation. One of the most remarkable finding in preterm tissues is the presence of huge amounts of stem/progenitor cells in multiple organs, including kidney, brain, heart, adrenals, and lungs. In other organs, such as liver, the completely different burden of cell types in preterm infants is mainly related to the different function of the liver during gestation, mainly focused on hematopoiesis, a function that is taken by bone marrow after birth. Our preliminary studies showed that the antigens expressed by stem/progenitors differ significantly from one organ to the next. Moreover, within each developing human tissue, reactivity for different stem cell markers also changes during gestation, according with the multiple differentiation steps encountered by each progenitor during development. A better knowledge of stem/progenitor cells of preterms will allow neonatologists to boost preterm organ maturation, favoring the differentiation of the multiple cells types that characterize each organ in at term neonates.

The preclinical and clinical implications of fetal adnexa derived mesenchymal stromal cells in wound healing therapy

Mesenchymal stromal cells (MSCs) isolated from fetal adnexa namely amniotic membrane/epithelium, amniotic fluid and umbilical cord have hogged the limelight in recent times, as a proposed alternative to MSCs from conventional sources. These cells which are identified as being in a developmentally primitive state have many advantages, the most important being the non-invasive nature of their isolation procedures, absence of ethical concerns, proliferation potential, differentiation abilities and low immunogenicity. In the present review, we are focusing on the potential preclinical and clinical applications of different cell types of fetal adnexa, in wound healing therapy. We also discuss the isolation-culture methods, cell surface marker expression, multi-lineage differentiation abilities, immune-modulatory capabilities and their homing property. Different mechanisms involved in the wound healing process and the role of stromal cells in therapeutic wound healing are highlighted. Further, we summarize the findings of the cell delivery systems in skin lesion models and paracrine functions of their secretome in the wound healing process. Overall, this holistic review outlines the research findings of fetal adnexa derived MSCs, their usefulness in wound healing therapy in human as well as in veterinary medicine.

Human amniotic mesenchymal stem cells to promote/suppress cancer: two sides of the same coin

Cancer is a leading cause of death in both developed and developing countries, and because of population growth and aging, it is a growing medical burden worldwide. With robust development in medicine, the use of stem cells has opened new treatment modalities in cancer therapy. In adult stem cells, mesenchymal stem cells (MSCs) are showing rising promise in cancer treatment due to their unique properties. Among different sources of MSCs, human amniotic fluid/membrane is an attractive and suitable reservoir. There are conflicting opinions about the role of human amniotic membrane/fluid mesenchymal stem cells (hAMSCS/hAFMSCs) in cancer, as some studies demonstrating the anticancer effects of these cells and others suggesting their progressive effects on cancer. This review focuses on recent findings about the role of hAMSCs/hAFMSCs in cancer treatment and summarizes the suppressing as well as promoting effects of these cells on cancer progression and underling mechanisms.

Human Amniotic Mesenchymal Stem Cells Promote Endogenous Bone Regeneration

Bone regeneration has become a research hotspot and therapeutic target in the field of bone and joint medicine. Stem cell-based therapy aims to promote endogenous regeneration and improves therapeutic effects and side-effects of traditional reconstruction of significant bone defects and disorders. Human amniotic mesenchymal stem cells (hAMSCs) are seed cells with superior paracrine functions on immune-regulation, anti-inflammation, and vascularized tissue regeneration. The present review summarized the source and characteristics of hAMSCs and analyzed their roles in tissue regeneration. Next, the therapeutic effects and mechanisms of hAMSCs in promoting bone regeneration of joint diseases and bone defects. Finally, the clinical application of hAMSCs from current clinical trials was analyzed. Although more studies are needed to confirm that hAMSC-based therapy to treat bone diseases, the clinical application prospect of the approach is worth investigating.

Human amnion-derived mesenchymal stem cells enhance the osteogenic differentiation of human adipose-derived stem cells by promoting adiponectin excretion via the APPL1-ERK1/2 signaling pathway

Human adipose-derived stem cells (HASCs) represent pluripotent cells capable of differentiating into the bone tissue. Meanwhile, human amnion-derived mesenchymal stem cells (HAMSCs) could cause mesenchymal stem cells to differentiate into the bone tissue. This work assessed the osteogenic effects exerted by HAMSCs on the potential of HASCs to form bone cells. Cell growth was evaluated flow-cytometrically. Differentiation into osteoblasts and mineral formation were assessed by chromogenic alkaline phosphatase activity substrate assay and Alizarin red S staining. Adiponectin (APN), the adipocytokine secreted by adipocytes, was evaluated by enzyme-linked immunosorbent assay. In this study, HAMSCs concentration-dependently induced growth, osteoblastic differentiation, and APN excretion in HASCs. Mechanistically, immunofluorescence and immunoblot revealed HAMSCs promoted cytosolic translocation of leucine zipper motif (APPL1) from the nucleus and induced extracellular signaling-regulated kinase 1/2 (ERK1/2) phosphorylation in HASCs. Furthermore, HAMSC effects were markedly blunted by pretreatment with APPL1 siRNA and U0126, an ERK1/2 signaling inhibitor with high selectivity. These results suggested that APN excretion is not suppressed by APPL1 knockdown in HASCs, but by ERK1/2 inhibition. These findings collectively indicate that HAMSCs induce the osteogenesis of HASCs by promoting APN excretion through APPL1-ERK1/2 activation.

A comparative study of HAMSCs/HBMSCs transwell and mixed coculture systems

Our previous studies indicated that a coculture system containing human amnion-derived mesenchymal stem cells (HAMSCs) and human bone marrow mesenchymal stem cells (HBMSCs) has the potential of application for bone regeneration. However, there is currently no enough comparative investigation between HAMSCs/HBMSCs transwell and mixed coculture systems. This study aimed to assess the phenotype and mechanisms regulated by indirect and direct coculture systems, respectively. Two in vitro models were employed with HAMSCs and HBMSCs at a ratio of 3:1, and then were analyzed by a series of processes, including flow cytometry, alkaline phosphatase (ALP) substrate assays, Alizarin red S staining, quantitative reverse transcription polymerase chain reaction (RT-qPCR), and Western blot analysis. We found that cell proliferation, ALP activity, mineralized matrix formation, and osteoblast-related mRNA expression were accelerated in transwell coculture system compared with mixed coculture system. Conditioned medium from transwell coculture system achieved an elevated level of vascular endothelial growth factor and induced more vascular structures in human umbilical vein endothelial cells than those of mixed coculture system. Moreover, we observed that transwell coculture system, promoted osteogenesis and angiogenesis by maintaining stemness through extracellular regulated protein kinases 1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) signaling pathway. U0126, a selective inhibitor of ERK1/2 MAPK signaling, significantly suppressed maintaining of the stemness-based effects on transwell coculture system. Taken together, our results compared the merits of two different models and clarified the role of HAMSCs/HBMSCs transwell coculture system in the development of bone tissue engineering. © 2019 IUBMB Life, 2019.

LncRNA H19 Knockdown in Human Amniotic Mesenchymal Stem Cells Suppresses Angiogenesis by Associating with EZH2 and Activating Vasohibin-1

Human amniotic mesenchymal stem cells (HAMSCs) are promising seed cells with great advantages in promoting angiogenesis. However, the mechanisms underlying angiogenesis facilitated by HAMSCs are still unclear. Long noncoding RNA H19 is involved in many biological processes, such as enhancing angiogenesis and proliferation, invasion, and migration of cancer cells. In this study, we constructed HAMSCs of stable low-expression H19 (HAMSC-shH19) and the scramble control (HAMSC-shNC) using lentiviral vectors, and in a three-dimensional coculture with human umbilical vein endothelial cells (HUVECs) to investigate the effect of H19 knockdown in HAMSCs on angiogenesis. Our results demonstrated that H19 knockdown significantly inhibited the angiogenic function of HAMSCs at an early stage in vitro and in vivo. The results of CCK8 and transwell assays demonstrated that the conditioned medium secreted by HAMSCs reduced proliferation and migration of HUVECs after downregulating H19. The angiogenesis factors expressed and secreted by HAMSC-shH19 were decreased compared with those secreted by the control, while angiogenesis inhibitors were elevated. Furthermore, we conducted chromatin immunoprecipitation and RNA-binding protein immunoprecipitation assays and found that H19 could interact with the histone methyltransferase Enhancer of Zeste homolog 2 (EZH2) and that H19 knockdown inhibited the ability of EZH2 to recruit methyl groups to the promoter region of the angiogenesis inhibitor gene vasohibin-1 (VASH1), thus increasing VASH1 expression and secretion of HAMSCs, suppressing angiogenesis. In summary, our study identified H19 as an important regulator in HAMSCs for promoting angiogenesis, which would help to construct ideal gene-modified seed cells to enhance angiogenesis in regenerative medicine.