MMP12 Deletion Preferentially Attenuates Axial Stiffening of Aging Arteries

Arterial stiffening is a hallmark of aging, but how aging affects the arterial response to pressure is still not completely understood, especially with regard to specific matrix metalloproteinases (MMPs). Here, we performed biaxial inflation–extension tests on C57BL/6 mice to study the effects of age and MMP12, a major arterial elastase, on arterial biomechanics. Aging from 2 to 24 months leads to both circumferential and axial stiffening with stretch, and these changes are associated with an increased wall thickness, a decreased inner radius–wall thickness ratio, and a decreased in vivo axial stretch. Analysis of in vivo stretch and stress–stretch curves with arteries from age- and sex-matched wild-type (WT) and MMP12-null arteries demonstrates that MMP12 deletion attenuates age-dependent arterial stiffening, mostly in the axial direction. MMP12 deletion also prevents the aging-associated decrease in the in vivo stretch and, in general, leads to an axial mechanics phenotype characteristic of much younger mice. Circumferential arterial mechanics were much less affected by deletion of MMP12. We conclude that the induction of MMP12 during aging preferentially promotes axial arterial stiffening.

INFLUENCE OF INTERMITTENT PNEUMATIC COMPRESSION ON ARTERIAL BED

Aim - to estimate the influence of intermittent pneumatic compression on arterial bed. Material and methods. The paper presents a literature review concerning the use of pneumatic compression in patients with peripheral artery disease. Results. Possibilities of pneumatic compression for prophylaxis and treatment of chronic ischemia in patients with peripheral artery disease are under discussion. Conclusion. The rapid growth of investigators’ interest in nonmedical methods of influence on arterial bed, and also the search for new and efficient methods and regimens highlight the significance of medical pneumatic compression. Currently, there is limited literature available about customization of pneumatic compression in accordance with nosology and individual indicators of blood circulation in lower extremities. As mentioned above, the most relevant and perspective direction is investigation of complex key indicators of arterial biomechanics with possibilities of the regimen correction, i.e. with implementation of feedback mechanism.