» Articles » PMID: 25708836

The Relationship of Autophagy Defects to Cartilage Damage During Joint Aging in a Mouse Model

Overview
Publisher Wiley
Specialty Rheumatology
Date 2015 Feb 25
PMID 25708836
Citations 104
Authors
Affiliations
Soon will be listed here.
Abstract

Objective: Aging is a main risk factor for osteo arthritis (OA), the most prevalent musculoskeletal disorder. Defects in autophagy, an essential cellular homeostasis mechanism, have recently been observed in OA articular cartilage. The objectives of this study were to establish the constitutive level of autophagy activation in normal cartilage and to monitor the temporal relationship between changes in autophagy and aging-related degradation of cartilage in a mouse model.

Methods: In GFP-LC3-transgenic mice, green fluorescent protein (GFP)-light chain 3 (LC3) is ubiquitously expressed, and the accumulation of GFP puncta, representing autophagosomes, was quantified by confocal microscopy as a measure of autophagy activation. Expression of the autophagy proteins autophagy-related protein 5 (ATG-5) and microtubule-associated protein 1 light chain 3 (LC3) was analyzed by immunohistochemistry. Cartilage cellularity, apoptotic cell death, and cartilage structural damage and changes in synovium and bone were examined by histology and immunohistochemistry.

Results: Basal autophagy activation was detected in liver and knee articular cartilage from young (6-month-old) mice, with higher levels in cartilage than in liver in the same animals. In 28-month-old mice, there was a statistically significant reduction in the total number of autophagic vesicles per cell (P < 0.01) and in the total area of vesicles per cell (P < 0.01) in the articular cartilage as compared to that from young 6-month-old mice. With increasing age, the expression of ATG-5 and LC3 decreased, and this was followed by a reduction in cartilage cellularity and an increase in the apoptosis marker poly(ADP-ribose) polymerase p85. Cartilage structural damage progressed in an age-dependent manner subsequent to the autophagy changes.

Conclusion: Autophagy is constitutively activated in normal cartilage. This is compromised with aging and precedes cartilage cell death and structural damage.

Citing Articles

NLRP3 overexpression exacerbated synovium tissue degeneration in juvenile collagen-induced arthritis.

Khadour F, Khadour Y, Xu T Sci Rep. 2025; 15(1):7024.

PMID: 40016261 PMC: 11868420. DOI: 10.1038/s41598-025-86720-6.


Metabolism-Related Adipokines and Metabolic Diseases: Their Role in Osteoarthritis.

Zhang Q, Zhao Y, Li L, Fan Q, Huang B, Du H J Inflamm Res. 2025; 18:1207-1233.

PMID: 39886385 PMC: 11780177. DOI: 10.2147/JIR.S499835.


Delivery of FGF18 using mRNA-LNP protects the cartilage against degeneration via alleviating chondrocyte senescence.

Kong K, Li B, Chang Y, Zhao C, Qiao H, Jin M J Nanobiotechnology. 2025; 23(1):34.

PMID: 39844298 PMC: 11753171. DOI: 10.1186/s12951-025-03103-9.


Investigating Angiogenesis-Related Biomarkers in Osteoarthritis Patients Through Transcriptomic Profiling.

Zheng Y, Fang M, Sanan S, Meng X, Huang J, Qian Y J Inflamm Res. 2024; 17:10681-10697.

PMID: 39677287 PMC: 11638479. DOI: 10.2147/JIR.S493889.


Endoplasmic reticulum stress-mediated apoptosis and autophagy in osteoarthritis: From molecular mechanisms to therapeutic applications.

Lu Y, Zhou J, Wang H, Gao H, Ning E, Shao Z Cell Stress Chaperones. 2024; 29(6):805-830.

PMID: 39571722 PMC: 11667160. DOI: 10.1016/j.cstres.2024.11.005.


References
1.
Madeo F, Tavernarakis N, Kroemer G . Can autophagy promote longevity?. Nat Cell Biol. 2010; 12(9):842-6. DOI: 10.1038/ncb0910-842. View

2.
Zhou H, Huang S . The complexes of mammalian target of rapamycin. Curr Protein Pept Sci. 2010; 11(6):409-24. PMC: 2928868. DOI: 10.2174/138920310791824093. View

3.
Ravikumar B, Sarkar S, Davies J, Futter M, Garcia-Arencibia M, Green-Thompson Z . Regulation of mammalian autophagy in physiology and pathophysiology. Physiol Rev. 2010; 90(4):1383-435. DOI: 10.1152/physrev.00030.2009. View

4.
Terkeltaub R, Yang B, Lotz M, Liu-Bryan R . Chondrocyte AMP-activated protein kinase activity suppresses matrix degradation responses to proinflammatory cytokines interleukin-1β and tumor necrosis factor α. Arthritis Rheum. 2011; 63(7):1928-37. PMC: 3128233. DOI: 10.1002/art.30333. View

5.
Carames B, Hasegawa A, Taniguchi N, Miyaki S, Blanco F, Lotz M . Autophagy activation by rapamycin reduces severity of experimental osteoarthritis. Ann Rheum Dis. 2011; 71(4):575-81. PMC: 3294168. DOI: 10.1136/annrheumdis-2011-200557. View