Research Paper Volume 13, Issue 24 pp 25903—25919
METTL14 benefits the mesenchymal stem cells in patients with steroid-associated osteonecrosis of the femoral head by regulating the m6A level of PTPN6
- 1 Department of Orthopedics, Henan Provincial People′s Hospital, Zhengzhou, Henan, China
- 2 Department of Mini-invasive Spinal Surgery, Third Hospital of Henan Province, Zhengzhou, Henan, China
Received: June 18, 2021 Accepted: November 22, 2021 Published: December 15, 2021
https://doi.org/10.18632/aging.203778How to Cite
Copyright: © 2021 Cheng et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Imbalanced osteogenic/adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is considered the core pathological characteristic of steroid-associated osteonecrosis of the femoral head (SONFH). N6-Methyladenosine (m6A) is the most common type of RNA modification in eukaryotic cells and participates in various physiological and pathological processes. However, the relationship between m6A modification and SONFH has not been reported. In the present study, we aimed to explore the roles of m6A modifications and methyltransferase METTL14 in SONFH. Our results showed that the m6A levels were down-regulated in femoral head tissues and BMSCs from SONFH patients, and this effect was attributed to the reduction of METTL14. Furthermore, METTL14 overexpression in BMSCs from SONFH patients enhanced cell proliferation and osteogenic differentiation. We further identified PTPN6 as the downstream target of METTL14 by mRNA sequencing. Mechanistically, METTL14 regulated PTPN6 expression by increasing PTPN6 mRNA stability in an m6A-dependent manner. Moreover, PTPN6 knockdown abrogated the beneficial effects of METTL14 overexpression on BMSCs. Additionally, we found that METTL14 activated the Wnt signaling pathway, and this effect was caused by the interaction of PTPN6 and GSK-3β. In conclusion, we elucidated the functional roles of METTL14 and m6A methylation in SONFH BMSCs and identified a novel RNA regulatory mechanism, providing a potential therapeutic target for SONFH.
Abbreviations
BMSC: bone marrow mesenchymal stem cell; SONFH: steroid-associated osteonecrosis of the femoral head; m6A: N6-methyladenosine; METTL14: methyltransferase 14; PTPN6: protein tyrosine phosphatase non-receptor type 6; GSK-3β: glycogen synthase kinase 3β; METTL3: methyltransferase 3; WTAP: WT1 associated protein; FTO: FTO alpha-ketoglutarate dependent dioxygenase; ALKBH5: alkB homolog 5; DMEM: Dulbecco’s modified Eagle’s medium; ALP: alkaline phosphatase; EdU: 5-ethynyl-2’-deoxyuridine; CCK-8: cell counting kit-8; qRT-PCR: quantitative real-time polymerase chain reaction; Co-IP: co-immunoprecipitation; MeRIP: RNA methylation immunoprecipitation; IHC: immunohistochemistry; ANOVA: one-way analysis of variance.