All-trans-retinoic acid inhibits chondrogenesis of rat embryo hindlimb bud mesenchymal cells by downregulating p53 expression

Abstract

Despite the well-established role of all-trans-retinoic acid (ATRA) in congenital clubfoot (CCF)-like deformities in in vivo models, the essential cellular and molecular targets and the signaling mechanisms for ATRA-induced CCF-like deformities remain to be elucidated. Recent studies have demonstrated that p53 and p21, expressed in the hindlimb bud mesenchyme, regulate cellular proliferation and differentiation, contributing to a significant proportion of embryonic CCF-like abnormalities. The objective of the present study was to investigate the mechanisms for ATRA-induced CCF, by assessing ATRA-regulated chondrogenesis in rat embryo hindlimb bud mesenchymal cells (rEHBMCs) in vitro. The experimental study was based on varying concentrations of ATRA exposure on embryonic day 12.5 rEHBMCs in vitro. The present study demonstrated that ATRA inhibited the proliferation of cells by stimulating apoptotic cell death of rEHBMCs. It was also observed that ATRA induced a dose-dependent reduction of cartilage nodules compared with the control group. Reverse transcription-polymerase chain reaction and western blotting assays revealed that the mRNA and protein expression of cartilage-specific molecules, including aggrecan, Sox9 and collagen, type II, α 1 (Col2a1), were downregulated by ATRA in a dose-dependent manner; the mRNA levels of p53 and p21 were dose-dependently upregulated from 16 to 20 h of incubation with ATRA, but dose-dependently downregulated from 24 to 48 h. Of note, p53 and p21 were regulated at the translational level in parallel with the transcription with rEHBMCs treated with ATRA. Furthermore, the immunofluorescent microscopy assays indicated that proteins of p53 and p21 were predominantly expressed in the cartilage nodules. The present study demonstrated that ATRA decreases the chondrogenesis of rEHBMCs by inhibiting cartilage-specific molecules, including aggrecan, Sox9 and Col2al, via regulating the expression of p53 and p21.

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

“…Interestingly, the osteogenic differentiation of MEPM cells from atRA-induced cleft palates were also weaker than MEPM cells from normal palates. We did not determine whether atRA could affect adipogenic and chondrogenic differentiation, but there are many other studies that show that atRA could block adipogenic differentiation by MEPM cells [73][74][75] and chondrogenic differentiation [76][77][78][79][80] . Our results showed that atRA regulated osteogenic differentiation through the disruption of MEPM cell stemness and pluripotency.…”

All-trans-retinoic acid suppresses rat embryo hindlimb bud mesenchymal chondrogenesis by modulating HoxD9 expression

“…DMSO alone was added to control cultures at a final concentration of 0.05% (v/v). The concentrations selected were based on a previous study [ 21 ].…”

Retinoic acid signalling in the development of the epidermis, the limbs and the secondary palate

“…Both in vivo and in vitro studies indicate that correct levels of RA are important for normal chondrogenesis in the developing limb (Lee et al, 2004a;Underhill and Weston, 1998;Weston et al, 2003). Numerous mouse studies indicate that either excess or deficiency of RA disrupts chondrogenesis through inhibition of proliferation and differentiation of mesenchymal precursor cells (Dranse et al, 2011;Tsuiki and Kishi, 1999;Wang et al, 2014aWang et al, , 2014bZhang et al, 2015;Zhou and Kochhar, 2004). Interestingly, RA-induced cartilage defects are more severe in the forearms than in the hands indicating that RA has position-related effects (Masuda et al, 2015).…”