scholarly journals All-trans Retinoic Acid Regulates miR-106a-5p Inhibition of Autophagic in Developing Cleft Palates

2020 ◽  
Author(s):  
Lungang Shi ◽  
Yan Liang ◽  
Lijing Yang ◽  
Binchen Li ◽  
Binna Zhang ◽  
...  

AbstractBackgroundAll-trans retinoic acid (atRA) results in cleft palate, but the cellular and molecular mechanisms underlying the teratogenic effects on palatal development have not been fully elucidated. Autophagy interruption has been reported to seriously affect embryonic-cell differentiation and development. This study aimed to verify whether atRA-induced cleft palate occurs because atRA blocks autophagy and stemness of embryonic palatal mesenchyme (MEPM) cells, which are maintained via the phosphatase and tensin homolog (PTEN)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) autophagic signaling pathway, and inhibits osteogenic-differentiation potential of MEPM cells, which could lead to the development of cleft palate.MethodsTo assess the stemness and pluripotency of MEPM cells, we analyzed their surfacemarkers using immunofluorescence (IF) and flow cytometry (FCM). Differentiation potentials, such as osteogenic, adipogenic, and chondrogenic differentiation, were induced. We also investigated the role of the PTEN/Akt/mTOR autophagic signaling pathway, which maintains the stemness and pluripotency of MEPM cells. Using transmission electron microscopy (TEM), Western blot analysis, quantitative reverse transcriptase polymerase chain reaction (RT-qPCR), messenger ribonucleic acid (mRNA) microarray, dual-luciferase reporter system, and exosomes, we found that atRA blocks autophagy and osteogenic differentiation of MEPM cells through micro-ribonucleic acid (miR)-106a-5p by targeting the PTEN/Akt/mTOR autophagic pathway.ResultsIn vitro purified MEPM cells expressed cell surface markers similar to those of mouse bone marrow stem cells. Additionally, in vitro MEPM cells were ectomesenchymal and expressed the neural-crest marker human natural killer-1 (HNK-1), the mesodermal marker vimentin, and the ectodermal marker nestin. They were also positive for in vitro MEPM markers, including platelet-derived growth factor alpha (PDGFRα), ephrin B1 (Efnb1), odd-skipped related 2 (Osr2), and Meox2, as well as for stemness markers including POU class 5 homeobox 4 (Oct4), Nanog, and sex-determining region Y-related HMG box 2 (Sox2). MEPM cell pluripotency was retained through activation of the PTEN/Akt/mTOR autophagic signaling pathway. We found that atRA blocked MEPM cell pluripotency to inhibit osteogenic differentiation via miR-106a-5p targeting of PTEN mRNA and subsequent suppression of the PTEN/Akt/mTOR autophagic pathway.ConclusionsIn vitro cultured MEPM cells are ectomesenchymal stem cells that have strong osteogenic differentiation potential, and MEPM pluripotency is regulated by autophagy via the PTEN/AKT/mTOR signaling pathway. atRA disrupts MEPM cell pluripotency through PTEN/AKT/mTOR signaling inactivation where miR-106a-5p targets PTEN mRNA to reduce osteogenic differentiation of MEPM cells and results in the development of cleft palates. Our findings provide new insight into the mechanism underlying the development of cleft palate, and miR-106a-5p may act as a prenatal screening biomarker for cleft palate as well as a new diagnostic and therapeutic target.

2018 ◽  
Vol 69 (7) ◽  
pp. 1817-1820
Author(s):  
Decebal Vasincu ◽  
Roxana Irina Iancu ◽  
Ionut Cazan ◽  
Gabriela Stoleriu ◽  
Marcel Costuleanu

The studies we performed targeted the effects of all-trans retinol (vitamin A) and some retinoid derivatives (including tretinoin or all-trans retinoic acid, retinyl propionate, 9-cis retinoic acid, 13-cis retinoic acid), as well as of tazarotenic acid on apoptosis of rat mesenchymal stem cells, cultured after isolation. Tazarotenic acid is considered to be relatively selective and a potent agonist for RARb and RARg and less for RARa. The same time, tazarotenic acid is not binding to RXRs (retinoid X receptors). The relevant analysis of our experimental results demonstrated that 13-cis retinoic acid was the most potent inducer of apoptosis of cultured mesenchymal stem cells of rat origin when compared to other retinoid derivatives, as follows: 13-cis retinoic acid ] 9-cis retinoic acid ] tazarotenic acid ] all-trans retinoic acid ] retinyl propionate ] retinol (or vitamin A). Very interesting and unexpected were the apoptotic effects of 1 �M tazarotenic acid for 24 hours in our experiments, very close to those induced by all-trans retinoic acid (tretinoin). The apoptosis induced by 13-cis retinoic acid, a principal activator of RARb and RARg, and that induced by 9-cis retinoic acid, a major activator of RXRs, suggests different pathways activated by these retinoid derivatives.


Author(s):  
PHU HUNG NGUYEN ◽  
Thu Ha Ngo ◽  
Thi Binh Luu

All trans retinoic acid (ATRA) plays an important role in many cellular processes and is a potent promising substance for cancer therapy. The self-renewal is a prominent feature of cancer stem cells that is tightly controlled by a number of specific genes, and is also mediated by the cell signaling pathways. The Notch signal pathway has been shown to be one of the few major molecular signaling pathways of cancer stem cells, which regulates self-renewal and survival of cancer stem cells. In this study, we showed that ATRA reduced the expression of important genes involved in self-renewal of cells including Sox2, KLF4, DMNT1 and MYC as well as TBGUT markers such as CD24, MUC1 and CD90. Furthermore, we indicate that the ATRA-induced expression of self-renewal genes and cancer stem cell markers of gastric cancer stem cells can be mediated by the regulation of the Notch signaling pathway.


2020 ◽  
Vol 8 (6) ◽  
pp. 495-510
Author(s):  
Manoj Kumar ◽  
Garima Sharma ◽  
Dinesh Singla ◽  
Sukhjeet Singh ◽  
Vandita Kakkar ◽  
...  

Background:: All-trans retinoic acid (ATRA) is widely employed in the treatment of various proliferative and inflammatory diseases. However, its therapeutic efficacy is imperiled due to its poor solubility and stability. Latter was surmounted by its incorporation into a solid matrix of lipidic nanoparticles (SLNs). Methods:: ATRA loaded SLNs (ATRA-SLNs) were prepared using a novel microemulsification technique (USPTO 9907758) and an optimal composition and were characterized in terms of morphology, differential scanning calorimetry (DSC), and powder X-ray diffraction studies (PXRD). In vitro release, oral plasma pharmacokinetics (in rats) and stability studies were also done. Results:: Rod-shaped ATRA-SLNs could successfully incorporate 3.7 mg/mL of ATRA, increasing its solubility (from 4.7 μg/mL) by 787 times, having an average particle size of 131.30 ± 5.0 nm and polydispersibility of 0.283. PXRD, DSC, and FTIR studies confirmed the formation of SLNs. Assay/total drug content and entrapment efficiency of ATRA-SLNs was 92.50 ± 2.10% and 84.60 ± 3.20% (n=6), respectively, which was maintained even on storage for one year under refrigerated conditions as an aqueous dispersion. In vitro release in 0.01 M phosphate buffer (pH 7.4) with 3% tween 80 was extended 12 times from 2h for free ATRA to 24 h for ATRA-SLNs depicting Korsmeyer Peppas release. Oral administration in rats showed 35.03 times enhanced bioavailability for ATRA-SLNs. Conclusion:: Present work reports preparation and evaluation of bioenhanced ATRA-SLNs containing a high concentration of ATRA (>15 times than that reported by others). Latter is attributed to the novel preparation process and intelligent selection of components. Lay Summary: All-trans retinoic acid (ATRA) shows an array of pharmacological activities but its efficacy is limited due to poor solubility, stability and side effects. In present study its solubility and efficacy is improved by 787 and 35.5 times, respectively upon incorporation into solid lipid nanoparticles (ATRA-SLNs). Latter extended its release by 12 times and provided stability for at least a year under refrigeration. A controlled and sustained release will reduce dose related side effects. ATRA-SLNs reported presently can thus be used in treatment /prophylaxis of disorders like cancers, tuberculosis, age related macular degeneration and acne and as an immune-booster.


Sign in / Sign up

Export Citation Format

Share Document