Matrix metalloproteinases in cerebrovascular disease

Area of Science:

• Neuroscience
• Biochemistry

Background:

• Cerebral ischemia and hemorrhage cause neuronal damage, extracellular matrix disruption, and increased capillary permeability.
• Free radicals and proteases are key substrates in cellular damage during these events.

Purpose of the Study:

• To investigate the role of proteases, specifically matrix metalloproteinases (MMPs) and serine proteases, in brain injury following cerebral ischemia and hemorrhage.
• To explore the potential therapeutic effects of MMP inhibitors in mitigating proteolytic damage and neuroinflammation.

Main Methods:

• The study discusses the involvement of MMPs and serine proteases, normally latent in the brain, which become activated during injury.
• It highlights the function of these enzymes in extracellular matrix remodeling and capillary permeability modulation.
• The intracerebral injection of type IV collagenase (an MMP) is cited as an example of blood-brain barrier disruption.

Main Results:

• Activated MMPs and serine proteases contribute to delayed injury and neuroinflammation.
• These enzymes degrade the extracellular matrix and increase capillary permeability, exemplified by MMP type IV collagenase opening the blood-brain barrier.
• While proteases are induced by various factors, their activity is regulated by inhibitors.

Conclusions:

• Proteolytic enzymes, including MMPs and serine proteases, play a significant role in the secondary injury cascade following cerebral ischemia and hemorrhage.
• Synthetic inhibitors targeting metalloproteinases show promise in reducing proteolytic tissue damage and potentially limiting secondary neuroinflammation.