Do different tendons exhibit the same response following chronic exposure to statins?

Area of Science:

• Biochemistry
• Orthopedics
• Pharmacology

Background:

• Statin therapy is widely used for cholesterol management.
• An increasing number of tendon injury cases have been linked to statin use.
• The precise mechanisms underlying statin-associated tendon pathologies remain unclear.

Purpose of the Study:

• To investigate the effects of atorvastatin and simvastatin on the extracellular matrix (ECM) of the deep digital flexor tendon (DDFT) and patellar tendon (PT).
• To elucidate potential mechanisms contributing to statin-induced tendon injuries.

Main Methods:

• Wistar rats were treated with varying doses of atorvastatin or simvastatin.
• Analysis included zymography, Western blotting for collagen I and non-collagenous proteins (NCP), and quantification of glycosaminoglycans (GAGs) and hydroxyproline.
• Tendon tissues examined were the deep digital flexor tendon (DDFT) and patellar tendon (PT).

Main Results:

• Statins altered NCP, hydroxyproline, GAGs, collagen I, and pro-matrix metalloproteinase-2 (MMP-2) activity in both DDFT and PT.
• Specific changes included increased NCP and GAGs in DDFT, and reduced NCP and GAGs in PT with statin treatment.
• Pro-MMP-2 activity was decreased across multiple statin treatment groups in both tendons.

Conclusions:

• Both atorvastatin and simvastatin induce significant alterations in the tendon ECM.
• These ECM modifications may predispose tendons to microdamage and rupture.
• Understanding these statin-induced ECM changes is crucial for addressing tendon injury risks.