Related Experiment Video
Updated: Nov 11, 2025
Fabrication and Characterization of Layer-By-Layer Janus Base Nano-Matrix to Promote Cartilage Regeneration
Published on: July 6, 2022
LncRNA MEG3 Protects Chondrocytes From IL-1β-Induced Inflammation via Regulating miR-9-5p/KLF4 Axis
Yijiang Huang1,2, Daosen Chen1,2, Zijian Yan1,2
1Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.
Background:
Osteoarthritis (OA) is a chronic degenerative disease of the joints characterized by articular cartilage damage, subchondral bone remodeling, osteophyte formation, and inflammatory changes. This work aims to investigate the protective role of long non-coding RNA (lncRNA) maternally expressed 3 (MEG3) against the apoptosis of chondrocytes.
Methods:
Chondrocyte cell lines, CHON-001, and ATDC5 were treated with different doses of interleukin-1β (IL-1β) to mimic the inflammatory response during OA pathogenesis. Quantitative real-time polymerase chain reaction was performed to measure MEG3, miR-9-5p, and Krüppel-like factor 4 (KLF4) mRNA expression levels. MEG3 and KLF4 overexpression plasmids, MEG3 shRNA, miR-9-5p mimics, and miR-9-5p inhibitors were transfected into the cells. Cell counting kit-8, wound healing assay, and flow cytometry were conducted to determine cell viability, migration, and apoptotic rate. Dual-luciferase reporter assay was adopted to verify the targeting relationships among MEG3, miR-9-5p, and KLF4. Western blot was used to detect KLF4 protein expression. Enzyme-linked immunosorbent assay was employed to measure the levels of inflammatory factors.
Results:
MEG3 expression in chondrocytes was down-regulated by the stimulation of IL-1β, and MEG3 negatively regulated miR-9-5p expression but positively regulated KLF4 expression. MEG3 overexpression strengthened the viability and migration of CHON-001 and ATDC5 cells but restrained the apoptosis and inflammatory response, while MEG3 knockdown had opposite effects. miR-9-5p inhibition or KLF4 overexpression could counteract the effects of MEG3 knockdown on chondrocytes. Besides that, MEG3 was proved to be a molecular sponge for miR-9-5p, and KLF4 was verified as the target of miR-9-5p.
Conclusion:
MEG3 can promote chondrocyte proliferation and migration and inhibit apoptosis and inflammation by sponging miR-9-5p to induce KLF4 expression, which provides a promising therapy target for OA treatment.
Insights
Long non-coding RNA MEG3 protects against osteoarthritis by inhibiting chondrocyte apoptosis and inflammation. It achieves this by regulating miR-9-5p and KLF4, offering a potential therapeutic target for OA.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Osteoarthritis (OA) is a degenerative joint disease marked by cartilage damage and inflammation.
- Chondrocyte apoptosis and inflammation are key pathological features of OA.
- Investigating protective mechanisms against chondrocyte apoptosis is crucial for OA treatment.
Purpose of the Study:
- To explore the protective role of long non-coding RNA maternally expressed 3 (MEG3) in chondrocytes against apoptosis.
- To elucidate the molecular mechanism involving MEG3, miR-9-5p, and Krüppel-like factor 4 (KLF4) in OA pathogenesis.
Main Methods:
- Chondrocyte cell lines were treated with interleukin-1β (IL-1β) to simulate OA inflammation.
- Quantitative real-time PCR, Western blot, and ELISA were used to assess gene/protein expression and inflammatory factors.
- Cell viability, migration, and apoptosis were evaluated using CCK-8, wound healing, and flow cytometry assays.
- Dual-luciferase reporter assays confirmed targeting relationships between MEG3, miR-9-5p, and KLF4.
Main Results:
- IL-1β stimulation downregulated MEG3 expression in chondrocytes.
- MEG3 overexpression enhanced chondrocyte viability and migration while inhibiting apoptosis and inflammation.
- MEG3 negatively regulated miR-9-5p and positively regulated KLF4 expression.
- MEG3 acts as a molecular sponge for miR-9-5p, and KLF4 is a target of miR-9-5p.
Conclusions:
- MEG3 protects chondrocytes by inhibiting apoptosis and inflammation.
- The mechanism involves MEG3 sponging miR-9-5p to upregulate KLF4 expression.
- MEG3 presents a potential therapeutic target for osteoarthritis treatment.
Related Concept Videos
02:39lncRNA - Long Non-coding RNAs
01:22MicroRNAs
01:22MicroRNAs
01:24T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
01:16TGF - β Signaling Pathway