Research on the mechanism of RNA m 6A modification in age-related idiopathic pulmonary fibrosis
10.3760/cma.j.issn.0254-9026.2025.01.009
- VernacularTitle:RNA m 6A修饰在衰老相关特发性肺纤维化的作用研究
- Author:
Li QIAN
1
;
Ziyue SUN
;
Yongkang HAN
;
Yufeng DU
;
Xiaohui WANG
;
Xuejun LIU
;
Dan LI
Author Information
1. 山西医科大学第一医院老年病科，太原 030001
- Publication Type:Journal Article
- Keywords:
Idiopathic pulmonary fibrosis;
Aging;
N 6-methyladenosine;
METTL3
- From:
Chinese Journal of Geriatrics
2025;44(1):51-59
- CountryChina
- Language:Chinese
-
Abstract:
Objective:This study aims to investigate the alterations in m 6A methylation associated with age-related idiopathic pulmonary fibrosis(IPF). Methods:By collecting peripheral blood samples from IPF patients, we investigated the changes in m6A modification levels of total RNA and key regulatory factors in elderly IPF patients.Then, the pulmonary fibrosis models of young and old mice were constructed for verification.A total of 10 IPF patients and 10 healthy controls were selected for this study.The m 6A methylation quantitative kit was employed to assess the m 6A modification levels of total RNA.The expression levels of key m 6A methylation regulators, METTL3, METTL14, and FTO, were quantified using qRT-PCR.Additionally, thirty-two healthy male C57BL/6 mice, comprising 16 mice aged 10-12 weeks and 16 mice aged 6-7 months, were divided into four groups: young control(A), young pulmonary fibrosis(B), aged control(C), and aged pulmonary fibrosis(D), with 8 mice in each group.Mice in groups B and D were intratracheally administered bleomycin to establish a pulmonary fibrosis model, while those in groups A and C received normal saline.Twenty-eight days post-model establishment, the mice were euthanized, and lung tissues were collected for analysis.Histological evaluations were performed using hematoxylin and eosin(HE)staining, Masson staining, hydroxyproline content determination, and immunohistochemistry to assess the extent of pulmonary fibrosis.The m 6A methylation quantification kit was also utilized to measure the m 6A modification levels of total RNA in lung tissue.Furthermore, the mRNA and protein expression levels of the methyltransferase METTL3 were assessed by qRT-PCR and Western blot experiments. Results:The level of m 6A modification was significantly elevated in the aged IPF patient group(0.36±0.03)compared to the control group t=4.882( P<0.05).Furthermore, the expression of METTL3 was markedly higher in the aged IPF patients( t=6.082), while the expression of METTL14 was significantly lower t=17.58( P<0.05).In contrast, the expression level of FTO did not exhibit a significant difference.It is hypothesized that the increased m 6A modification of total RNA in aged IPF patients is closely associated with METTL3.Furthermore, the degree of lung fibrosis in aged mice was more severe than that in young mice.Immunohistochemistry results indicated that TGF-β1 expression was elevated in the lung fibrosis group, with higher levels observed in group D compared to group B( t=5.891, P<0.05), and in group C compared to group A t=4.135( P<0.05).The percentage of positive area for α-SMA was significantly greater in the lung fibrosis mouse model than in the control group t=20.08( P<0.05).The level of m 6A modification was increased in both lung fibrosis groups relative to the normal control group( P<0.05), although no significant difference was found between group D and group B. Overall, METTL3 mRNA and protein expression were upregulated in the lung fibrosis group, with expression in group D being lower than in group B( P<0.05). Conclusions:The level of m 6A modification is elevated in pulmonary fibrosis, and the expression of METTL3 is upregulated in this condition.The downregulation of METTL3 may be associated with the extent of aging, which subsequently exacerbates the progression of pulmonary fibrosis.
