Gap junctions in IL-1β-mediated cell survival response to strain
Jie Qi1, Liqun Chi, Donald Bynum
1Flexcell International, Hillsborough, NC 27278, USA.
Journal of Applied Physiology (Bethesda, Md. : 1985)
|January 8, 2011
Summary
Mechanical strain can cause tenocyte cell death, mimicking tendinopathy. Low-dose interleukin-1β (IL-1β) protects these cells by upregulating connexin 43, offering potential therapeutic targets for tendon injury.
Area of Science:
- Biomedical Engineering
- Cell Biology
- Orthopedics
Background:
- Mechanical stimuli are crucial for connective tissue health, but excessive loading can cause tendinopathy.
- Interleukin-1β (IL-1β) is typically viewed as pro-inflammatory, yet it may influence cell survival pathways.
Purpose of the Study:
- To investigate if cyclic strain induces tenocyte cell death and a tendinopathy gene expression profile.
- To determine if low-dose IL-1β can protect tenocytes from strain-induced damage.
Main Methods:
- Human tenocytes were cultured in 3D collagen hydrogels and subjected to cyclic strain.
- Gene expression analysis (RT-PCR) was performed with and without IL-1β treatment.
- Connexin 43 expression was assessed for its role in cell survival.
Main Results:
- Cyclic strain induced cell death and altered gene expression consistent with tendinopathy.
- IL-1β treatment reversed these strain-induced changes to control levels.
- IL-1β appeared to promote cell survival by upregulating connexin 43.
Conclusions:
- Cyclic strain contributes to tendinopathy pathogenesis through cell death and altered gene expression.
- IL-1β demonstrates a protective role against strain-induced tenocyte injury.
- Connexin 43 is a potential mediator of IL-1β's protective effects, offering new therapeutic avenues for tendinopathy.
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