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Updated: Mar 28, 2026
Software-Assisted Quantitative Measurement of Osteoarthritic Subchondral Bone Thickness
Published on: March 18, 2022
Hsa-miR-15a exerts protective effects against osteoarthritis by targeting aggrecanase-2 (ADAMTS5) in human
1Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Beijing 100730, P.R. China.
Abstract:
The aim of the present study was to examine the expression levels and role of hsa-miR-15a in osteoarthritis (OA), as well as the associated mechanisms. The expression levels of hsa-miR-15a and A disintegrin-like and metalloprotease (reprolysin type) with thrombospondin type 1 motif, 5 (ADAMTS5, also known as aggrecanase-2) were measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in both OA and normal chondrocytes. hsa-miR‑21 mimics or antisense oligonucleotides (ASO) were co-transfected into the chondrocytes to examine the effects on the putative binding sites compared with the negative control (NC)-mimics or NC-ASO. The relative ADAMTS5 mRNA and protein levels were measured by RT-qPCR and western blot anlaysis, respectively. Moreover, after inhibiting the expression of hsa‑miR‑15a and ADAMTS5 by ASO and small interfering RNA (siRNA), respectively, the amounts of proteoglycan and collagen in the cellular matrix and medium were determined. Additionally, the expression levels of collagen II were measured by western blot analysis. hsa‑miR‑15a expression was downregulated, but ADAMTS5 expression was upregulated in the human OA chondrocytes compared to the normal chondrocytes. Luciferase reporter assay confirmed that the hsa‑miR‑15a binding site was in the ADAMTS5 gene 3'-untranslated region (3'-UTR), and ADAMTS5 was negatively regulated by hsa‑miR‑15a. The downregulation of hsa‑miR‑15a decreased the aggregation of proteoglycan and the collagen content, but increased the release of proteoglycan and collagen; total collagen production was significantly lower, and collagenase activity was markedly higher. The downregulation of ADAMTS5 increased the aggregation of proteoglycan and the collagen content, but decreased the release of proteoglycan and collagen, along with total collagen production. Moreover, collagenase activity was markedly lower. The findings of our study suggest that hsa‑miR‑15a exerts protective effects against OA by targeting ADAMTS5 in human chondrocytes.
Insights
MicroRNA hsa-miR-15a is downregulated in osteoarthritis (OA) and protects cartilage by targeting ADAMTS5 (a disintegrin-like and metalloprotease with thrombospondin type 1 motif, 5). Restoring hsa-miR-15a levels may offer a therapeutic strategy for OA.
Area of Science:
- Biochemistry
- Molecular Biology
- Genetics
Background:
- Osteoarthritis (OA) is a degenerative joint disease characterized by cartilage breakdown.
- MicroRNAs (miRNAs) play crucial roles in regulating gene expression and are implicated in OA pathogenesis.
- Understanding the specific roles of miRNAs in OA is essential for developing targeted therapies.
Purpose of the Study:
- To investigate the expression levels and functional role of hsa-miR-15a in human osteoarthritis (OA) chondrocytes.
- To elucidate the underlying molecular mechanisms by which hsa-miR-15a influences OA pathology, specifically its interaction with ADAMTS5.
- To assess the potential of modulating hsa-miR-15a as a therapeutic strategy for OA.
Main Methods:
- Quantitative reverse transcription polymerase chain reaction (RT-qPCR) to measure hsa-miR-15a and ADAMTS5 (a disintegrin-like and metalloprotease with thrombospondin type 1 motif, 5) expression.
- Chondrocyte transfection with hsa-miR-15a mimics or antisense oligonucleotides (ASO) to modulate its expression.
- Western blot analysis to determine ADAMTS5 protein levels and collagen II expression.
- Assays to quantify proteoglycan and collagen content and release in the cellular matrix and medium.
- Luciferase reporter assay to confirm the binding site of hsa-miR-15a in the ADAMTS5 gene.
Main Results:
- hsa-miR-15a expression was significantly downregulated in OA chondrocytes compared to normal chondrocytes.
- ADAMTS5 expression was upregulated in OA chondrocytes, and hsa-miR-15a was confirmed to directly target and negatively regulate ADAMTS5.
- Downregulation of hsa-miR-15a led to decreased proteoglycan and collagen aggregation, increased release of these matrix components, reduced total collagen production, and higher collagenase activity.
- Conversely, downregulation of ADAMTS5 improved proteoglycan and collagen content, reduced their release, and decreased collagenase activity.
Conclusions:
- hsa-miR-15a plays a protective role in osteoarthritis by targeting and downregulating ADAMTS5 in human chondrocytes.
- The findings suggest that hsa-miR-15a acts as a suppressor of cartilage degradation in OA.
- Modulating hsa-miR-15a expression represents a potential therapeutic avenue for osteoarthritis treatment.
