scholarly journals 5-Aza-2′-Deoxycytidine and Valproic Acid in Combination with CHIR99021 and A83-01 Induce Pluripotency Genes Expression in Human Adult Somatic Cells

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 1909
Author(s):  
Alain Aguirre-Vázquez ◽  
Luis A. Salazar-Olivo ◽  
Xóchitl Flores-Ponce ◽  
Ana L. Arriaga-Guerrero ◽  
Dariela Garza-Rodríguez ◽  
...  

A generation of induced pluripotent stem cells (iPSC) by ectopic expression of OCT4, SOX2, KLF4, and c-MYC has established promising opportunities for stem cell research, drug discovery, and disease modeling. While this forced genetic expression represents an advantage, there will always be an issue with genomic instability and transient pluripotency genes reactivation that might preclude their clinical application. During the reprogramming process, a somatic cell must undergo several epigenetic modifications to induce groups of genes capable of reactivating the endogenous pluripotency core. Here, looking to increase the reprograming efficiency in somatic cells, we evaluated the effect of epigenetic molecules 5-aza-2′-deoxycytidine (5AZ) and valproic acid (VPA) and two small molecules reported as reprogramming enhancers, CHIR99021 and A83-01, on the expression of pluripotency genes and the methylation profile of the OCT4 promoter in a human dermal fibroblasts cell strain. The addition of this cocktail to culture medium increased the expression of OCT4, SOX2, and KLF4 expression by 2.1-fold, 8.5-fold, and 2-fold, respectively, with respect to controls; concomitantly, a reduction in methylated CpG sites in OCT4 promoter region was observed. The epigenetic cocktail also induced the expression of the metastasis-associated gene S100A4. However, the epigenetic cocktail did not induce the morphological changes characteristic of the reprogramming process. In summary, 5AZ, VPA, CHIR99021, and A83-01 induced the expression of OCT4 and SOX2, two critical genes for iPSC. Future studies will allow us to precise the mechanisms by which these compounds exert their reprogramming effects.

2017 ◽  
Vol 358 (2) ◽  
pp. 290-300 ◽  
Author(s):  
João Charneca ◽  
Ana Catarina Matias ◽  
Ana Luisa Escapa ◽  
Catarina Fernandes ◽  
André Alves ◽  
...  

2020 ◽  
Vol 10 (20) ◽  
pp. 7372
Author(s):  
Hyeonjin Cha ◽  
Jaeyoung Lee ◽  
Hee Ho Park ◽  
Ju Hyun Park

The generation of functional osteoblasts from human somatic cells could provide an alternative means of regenerative therapy for bone disorders such as osteoporosis. In this study, we demonstrated the direct phenotypic conversion of human dermal fibroblasts (HDFs) into osteoblasts by culturing them in osteogenic medium supplemented with valproic acid (VPA), a histone deacetylase (HDAC) inhibitor. HDFs cultured with the VPA in osteogenic medium exhibited expression of alkaline phosphatase and deposition of mineralized calcium matrices, which are phenotypical characteristics of functional osteoblasts. They also expressed osteoblast-specific genes such as alkaline phosphatase, osteopontin, and bone sialoprotein, which demonstrated their direct conversion into osteoblasts. In addition, co-treatment with VPA and a specific inhibitor for activin-like kinase 5 (ALK5i II) had a synergistic effect on direct conversion. It is considered that the inductive effect of VPA on the conversion into osteoblast-lineage is due to the opening of the nucleosome structure by HDAC inhibitor, which facilitates chromatin remodeling and cellular reprogramming. Our findings provide a novel insight into the direct conversion of human somatic cells into transgene-free osteoblasts with small chemical compounds, thus making bone regeneration using cellular reprogramming strategy more clinically feasible.


2012 ◽  
Vol 24 (1) ◽  
pp. 223 ◽  
Author(s):  
Z. Tancos ◽  
O. Ujhelly ◽  
M. K. Pirity ◽  
A. Dinnyes

Induced pluripotent stem cells (iPSC) technology, which allows direct reprogramming of somatic cells to a pluripotent state, is a promising tool for gene-function studies disease modelling, drug screening, toxicology tests and to generate knockout animal models. The goal of the current work was to close the gap in knowledge with regard to the molecular biological background for rabbit iPS work by isolating the putative pluripotency genes from the rabbit, based on the sequences published for other species. The sequence of known pluripotency genes (Oct4, Sox2, Klf4, c-Myc, Nanog) were analysed and primers designed based on the similarity of sequences. Sequences of each individual rabbit pluripotency gene was compared to other vertebrates (e.g. human, mouse, bovine) phylogenetically. Rabbit ESCs and blastocyst stage embryos were collected from superovulated rabbits to isolate total RNA. Genes of interest were amplified using RT-PCR and electrophoretically separated for cDNA fragment isolation. Isolated and subcloned cDNA fragments were sequenced and analysed. Our results showed that after restriction digestion the size of amplified and cloned rabbit Oct4, Sox2, Klf4, c-Myc and Nanog gene fragments correspond to the expected amplicon size. Furthermore, sequence confirmation by DNA sequencing has been completed in the case of Oct4, c-Myc, Klf4 and Nanog. The homology of these genes to that of their mouse and human orthologs were as follows: Oct4: at Na level 79% homologue to mouse, 85% homologue to human, at Aa level 81% homologue to mouse, 90% homologue to human; Klf4: at Na level 98% homologue to mouse, 85% homologue to human, at Aa level 95% homologue to mouse, 84% homologue to human; c-myc: at Na level 88% homologue to mouse, 92% homologue to human, at Aa level 91% homologue to mouse and 94% homologue to human; Nanog: at Na level 71% homologue to mouse, 78% homologue to human, at Aa level 55% homologue to mouse, 66% homologue to human. In conclusion, we have revealed differences at both Na and Aa level in all four major rabbit pluripotency gene sequences in comparison to their mammalian orthologs which might partially explain difficulties in generation of rabbit iPSC capable of germline transmission. Our further goal is to apply rabbit specific pluripotency genes to reprogram somatic cells and generate iPSC more efficiently than by using mouse or human genes. This work was supported by grants from Plurabbit, OMFB-00130/2010 ANR-NKTH; NKTH-OTKA-EU-7KP HUMAN-MB08-C-80-205; EU FP7 (AniStem, PIAP-GA-2011-286264PartnErS, PIAP-GA-2008-218205; InduStem, PIAP-GA-2008-230675; InduHeart, PEOPLE-IRG-2008-234390; InduVir, PEOPLE-IRG-2009-245808; PluriSys, HEALTH-2007-B-223485).


2011 ◽  
Vol 23 (1) ◽  
pp. 249
Author(s):  
D. Kumar ◽  
D. Malakar ◽  
R. Dutta ◽  
S. Garg ◽  
S. Sahu ◽  
...  

Embryonic stem cells (ESC) are derived from the inner cell mass of blastocysts and proliferate extensively while maintaining pluripotency. They can be used for the treatment of juvenile diabetes, Parkinson’s disease, heart failure, and spinal cord injury. However, the use of embryos and tissue rejection remain concerns for ESC transplantation. Reprogramming of somatic cells may be done by different methods such as somatic cell nuclear transfer (Wilmut et al. 1997), fusion of somatic cells (Cowen et al. 2005), treatment with the extract of the pluripotent stem cells (Johnson Rajasingh 2008), and by the stable ectopic expression of defined factors in the somatic cells (Takahashi and Yamanaka 2006). Several transcription factors, including Oct3/4 (Nichols et al. 1998; Niwa et al. 2000), Sox2 (Avilion et al. 2003), and Nanog (Chambers et al. 2003; Mitsui et al. 2003), function in the maintenance of pluripotency in both early embryos and ESC. Takahashi and Yamanaka reported reprogramming the fibroblast cells into stem cells by introducing Oct3/4, Sox2, c-Myc, and Klf4 in mouse embryonic and adult fibroblasts. Yu et al. (2007) demonstrated that four transcription factors (OCT-4, SOX2, NANOG, and LIN28) are sufficient to reprogramme human somatic cells to pluripotent stem cells that exhibit the essential characteristics of ESC. Nakagawa et al. (2008) used three factors (OCT3/4, SOX2, and KLF4) for human iPS cell production from somatic cells. We are trying to reprogramme the adult goat fibroblast cells in induced pluripotent stem cells by using ectopic expression of transcription factors such as Oct-4, Sox2, Nanog, and Lin28. We collected the ovaries from a slaughtered animal from Delhi and collected the oocytes from ovaries. Then after the collection, A and B grade oocytes were selected. Selected oocytes were processed and incubated in in vitro maturation media for 24 h. We collected semen from a male goat, and it was processed and capacitated in sperm TALP. Capacitated sperms were used for IVF of the in vitro matured oocytes in ferTALP. After 12 h sperm were washed from oocytes in embryo developing media (EDM), and oocytes were cultured (in vitro) in EDM. After 24 h cleavage occurred. The cleaved embryos were cultured for 6 to 7 days. At the 7th day, we got blastocysts. From these blastocysts, inner cell mass was isolated enzymatically and cultured to get ESC. The ESC were cultured for 7 passages and used for RNA isolation. The RNA was isolated from these stem cells by the Trizol method. Complementary DNA was prepared by RT-PCR. Using gene-specific primer for Oct-4, Nanog, and Sox2, DNA was amplified. The DNA for the Oct-4, Nanog, and Sox2 genes was cloned in pJET cloning vector and transformed in Top10 E. coli competence cells. After screening, plasmid was isolated and sent for sequencing. Sequences were analysed and the complete open reading frame was created for Oct-4, Nanog, and Sox2.


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Ji-feng Kang ◽  
Bei-sha Tang ◽  
Ji-feng Guo

In recent years, induced pluripotent stem cells (iPSCs) were widely used for investigating the mechanisms of Parkinson’s disease (PD). Somatic cells from patients withSNCA(α-synuclein),LRRK2(leucine-rich repeat kinase 2),PINK1(PTEN induced putative kinase 1),Parkinmutations, and at-risk individuals carryingGBA(β-glucocerebrosidase) mutations have been successfully induced to iPSCs and subsequently differentiated into dopaminergic (DA) neurons. Importantly, some PD-related cell phenotypes, includingα-synuclein aggregation, mitophagy, damaged mitochondrial DNA, and mitochondrial dysfunction, have been described in these iPSCs models, which further investigated the pathogenesis of PD. In 2007, Takahashi et al. and Vodyanik et al. generated iPSCs from human somatic cells for the first time. Since then, patients derived iPSCs were applied for disease modeling, drug discovery and screening, autologous cell replacement therapy, and other biological applications. iPSC research has now become a hot topic in a wide range of fields. This review summarizes the recent progress of PD patients derived iPSC models in pathogenic mechanism investigation and potential clinical applications, especially their promising strategy in pharmacological study and DA neurons transplantation therapy. However, the challenges of iPSC transplantation still exist, and it has a long way to go before it can be used in clinical application.


2011 ◽  
Vol 29 (27_suppl) ◽  
pp. 227-227
Author(s):  
S. M. L. Lim ◽  
I. Aksoy ◽  
K. G. C. Lim ◽  
J. Karuppasamy ◽  
U. Divakar ◽  
...  

227 Background: Recent advances in pluripotent stem cell biology offer patient-specific disease models to investigate in vitro mechanisms of tumorigenesis. Induced pluripotent stem (iPS) cells were originally derived by reprogramming of human dermal fibroblasts through ectopic expression of pluripotency–associated transcription factors. A limitation to the use of dermal fibroblasts as the starting cell type for reprogramming is that it usually takes weeks to expand cells from a single biopsy, and the efficiency of the process is very low. In contrast, a large number of adipose-derived mesenchymal stromal cells (Ad-MSCs) can be easily obtained from the stroma of human breast tissue, without the time-consuming steps of cell expansion. Here we investigated the ability to induce pluripotency in committed, Ad-MSCs derived from the stroma of breast tissue. Methods: The aim of this study is to investigate the potential of using Ad-MSCs derived from surgically discarded breast stromal tissue to generate human iPS. Discarded tissue during surgical procedures was processed in vitro and Ad-MSCs were derived. These Ad-MSCs were then used to generate iPS cells by ectopic expression of “Yamanaka’s cocktail” containing OCT4, SOX2, KLF4 and c-MYC. Results: The success rate in generating iPS cells from human Ad-MSCs derived from breast stromal tissue is very high compared to the use of dermal fibroblasts. In our study, almost all human Ad-MSC cell lines can be reprogrammed into iPS cells, which share the same characteristics as skin fibroblast-derived iPS cells and human embryonic stem cells in their morphology, gene expression profile and differentiation capacities. Conclusions: We are now optimizing this approach and making it more clinically relevant by adopting an integration-free method to deliver the reprogramming factors. The successful reprogramming of breast stromal-derived Ad-MSCs into iPS cells may provide a valuable source of patient-specific iPS cells to study the mechanism of tumorigenesis in patients with breast cancer.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Heidrun Steinle ◽  
Marbod Weber ◽  
Andreas Behring ◽  
Ulrike Mau-Holzmann ◽  
Christian Schlensak ◽  
...  

The reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) is gaining in importance in the fields of regenerative medicine, tissue engineering, and disease modeling. Patient-specific iPSCs have as an unlimited cell source a tremendous potential for generating various types of autologous cells. For the future clinical applicability of these iPSC-derived cells, the generation of iPSCs via nongenome integrating methods and the efficient reprogramming of patients’ somatic cells are required. In this study, 2 different RNA-based footprint-free methods for the generation of iPSCs were compared: the use of synthetic modified messenger RNAs (mRNAs) or self-replicating RNAs (srRNAs) encoding the reprogramming factors and GFP. Using both RNA-based methods, integration-free iPSCs without genomic alterations were obtained. The pluripotency characteristics identified by specific marker detection and the in vitro and in vivo trilineage differentiation capacity were comparable. Moreover, the incorporation of a GFP encoding sequence into the srRNA enabled a direct and convenient monitoring of the reprogramming procedure and the successful detection of srRNA translation in the transfected cells. Nevertheless, the use of a single srRNA to induce pluripotency was less time consuming, faster, and more efficient than the daily transfection of cells with synthetic mRNAs. Therefore, we believe that the srRNA-based approach might be more appropriate and efficient for the reprogramming of different types of somatic cells for clinical applications.


2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Chingiz Underbayev ◽  
Siddha Kasar ◽  
Yao Yuan ◽  
Elizabeth Raveche

Human disease animal models are absolutely invaluable tools for our understanding of mechanisms involved in both physiological and pathological processes. By studying various genetic abnormalities in these organisms we can get a better insight into potential candidate genes responsible for human disease development. To this point a mouse represents one of the most used and convenient species for human disease modeling. Hundreds if not thousands of inbred, congenic, and transgenic mouse models have been created and are now extensively utilized in the research labs worldwide. Importantly, pluripotent stem cells play a significant role in developing new genetically engineered mice with the desired human disease-like phenotype. Induced pluripotent stem (iPS) cells which represent reprogramming of somatic cells into pluripotent stem cells represent a significant advancement in research armament. The novel application of microRNA manipulation both in the generation of iPS cells and subsequent lineage-directed differentiation is discussed. Potential applications of induced pluripotent stem cell—a relatively new type of pluripotent stem cells—for human disease modeling by employing human iPS cells derived from normal and diseased somatic cells and iPS cells derived from mouse models of human disease may lead to uncovering of disease mechanisms and novel therapies.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8952 ◽  
Author(s):  
Georgina Peñalosa-Ruiz ◽  
Klaas W. Mulder ◽  
Gert Jan C. Veenstra

Reprogramming somatic cells to induced pluripotent stem cells (iPSC) succeeds only in a small fraction of cells within the population. Reprogramming occurs in distinctive stages, each facing its own bottlenecks. It initiates with overexpression of transcription factors OCT4, SOX2, KLF4 and c-MYC (OSKM) in somatic cells such as mouse embryonic fibroblasts (MEFs). OSKM bind chromatin, silencing the somatic identity and starting the stepwise reactivation of the pluripotency programme. However, inefficient suppression of the somatic lineage leads to unwanted epigenetic memory from the tissue of origin, even in successfully generated iPSCs. Thus, it is essential to shed more light on chromatin regulators and processes involved in dissolving the somatic identity. Recent work characterised the role of transcriptional corepressors NCOR1 and NCOR2 (also known as NCoR and SMRT), showing that they cooperate with c-MYC to silence pluripotency genes during late reprogramming stages. NCOR1/NCOR2 were also proposed to be involved in silencing fibroblast identity, however it is unclear how this happens. Here, we shed light on the role of NCOR1 in early reprogramming. We show that siRNA-mediated ablation of NCOR1 and OCT4 results in very similar phenotypes, including transcriptomic changes and highly correlated high-content colony phenotypes. Both NCOR1 and OCT4 bind to promoters co-occupied by c-MYC in MEFs. During early reprogramming, downregulation of one group of somatic MEF-expressed genes requires both NCOR1 and OCT4, whereas another group of MEF-expressed genes is downregulated by NCOR1 but not OCT4. Our data suggest that NCOR1, assisted by OCT4 and c-MYC, facilitates transcriptional repression of genes with high expression in MEFs, which is necessary to bypass an early reprogramming block; this way, NCOR1 facilitates early reprogramming progression.


2020 ◽  
Author(s):  
Immacolata Belviso ◽  
Veronica Romano ◽  
Daria Nurzynska ◽  
Clotilde Castaldo ◽  
Franca Di Meglio

Induced Pluripotent Stem cells (iPSC) are adult somatic cells genetically reprogrammed to an embryonic stem cell-like state. Due to their autologous origin from adult somatic cells, iPSCs are considered a tremendously valuable tool for regenerative medicine, disease modeling, drug discovery and testing. iPSCs were first obtained by introducing specific transcription factors through retroviral transfection. However, cell reprogramming obtained by integrating methods prevent clinical application of iPSC because of potential risk for infection, teratomas and genomic instability. Therefore, several integration-free alternate methods have been developed and tested thus far to overcome safety issues. The present chapter provides an overview and a critical analysis of advantages and disadvantages of non-integrating methods used to generate iPSCs.


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