Oxidative stress induces senescence in chondrocytes
Anita Brandl1, Andreas Hartmann, Volker Bechmann
1Department of Anesthesiology, University Hospital Regensburg, 93042 Regensburg, Germany. anita.brandl@klinik.uni-regensburg.de
Summary
Oxidative stress accelerates cellular aging and telomere shortening in human chondrocytes, particularly in senescent cells. These aged cells exhibit reduced tolerance to oxidative damage, impacting cartilage health.
Area of Science:
- Biomedical Science
- Cell Biology
- Aging Research
Background:
- Cellular senescence is a stress-induced response.
- Articular cartilage chondrocytes, in an avascular tissue, have unknown responses to oxidative stress.
- Osteoarthritis involves chondrocyte dysfunction.
Purpose of the Study:
- Investigate oxidative stress effects on human osteoarthritic chondrocyte proliferation, morphology, and telomere-linked stress response.
- Examine responses to acute and prolonged hydrogen peroxide exposure.
- Determine the impact on cellular senescence and aging.
Main Methods:
- Human osteoarthritic chondrocytes subjected to oxidative stress (hydrogen peroxide).
- Assessed proliferation potential and cytological features.
- Measured telomere length (telomere restriction fragment assay) and gene expression (RT-PCR) for p21, TRF2, SIRT1, and XRCC5.
Main Results:
- Sub-lethal oxidative stress induced cell-cycle arrest, senescence markers (β-galactosidase positivity), and accelerated telomere attrition.
- Prolonged oxidative treatment did not affect proliferation or morphology.
- Senescent cells showed distinct responses to oxidative stress and reduced tolerance.
- Oxidative insult upregulated p21, TRF2, SIRT1, and XRCC5, with decreased SIRT1/XRCC5 in aging cells.
Conclusions:
- Oxidative stress significantly accelerates telomere shortening and cellular aging in chondrocytes.
- Senescent chondrocytes are more vulnerable to oxidative damage.
- Findings highlight the role of oxidative stress in osteoarthritis pathogenesis and chondrocyte aging.
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