The kallikrein system in retinal damage/protection

Area of Science:

• Biochemistry
• Ophthalmology
• Protease Function

Background:

• Kallikrein is a serine protease within the kallikrein-kinnin system.
• Kallikrein, sourced from plasma or tissue, impacts various eye conditions.
• Plasma kallikrein exacerbates retinal vascular permeability and intraocular hemorrhage.

Purpose of the Study:

• To investigate the contrasting roles of plasma and tissue kallikrein in ocular diseases.
• To elucidate the protective mechanisms of tissue kallikrein in the eye.
• To explore the therapeutic potential of tissue kallikrein for VEGF-related eye diseases.

Main Methods:

• Comparative analysis of plasma and tissue kallikrein activities.
• Assessment of retinal vascular permeability and neovascularization.
• Investigation of kallikrein's interaction with vascular endothelial growth factor (VEGF).

Main Results:

• Tissue kallikrein normalizes retinal vasopermeability.
• Tissue kallikrein inhibits retinal neovascularization and ischemic injury.
• Tissue kallikrein's protective effect is linked to vascular endothelial growth factor (VEGF) cleavage.

Conclusions:

• Tissue kallikrein demonstrates protective effects in ocular conditions, contrasting with plasma kallikrein.
• The cleavage of VEGF by tissue kallikrein is a key protective mechanism.
• Tissue kallikrein holds potential for treating eye diseases associated with VEGF production.