Vascular Aging

Artery Changes and Pathologies With Aging

• Vascular Smooth Muscle Proliferation

Aging increases the thickness of the wall of the artery, by an increase in vascular smooth muscle, and a remodeling of the vascular wall. Such proliferation is an early pathology leading to the development of  arteriosclerosis.

• Vascular Dysfunction

The functional ability of the arteries is impaired with increasing age.  

o   Decreased Vasodilation

Arteries lose the ability to relax and dilate. Many factors contribute to this including the loss of endothelium cells, the inability of the endothelium to synthesize nitric oxide for relaxation, and increasing stiffness of the vessels. due to loss of elasticity.

o   Increased Inflammatory NF-kappaB Activity

NF-kappaB stimulates an increase in inflammation, which increases oxidative stress in the endothelium, andcontributes to vascular dysfunction associated with aging.

o   Increased Vasoconstriction

Endothelin-1 (vasoconstriction protein) levels are increased in the vascular endothelium. Aging raises levels of endothelin-1, in response to increased inflammation

o   Loss of Healthy Endothelium (Arterial Lining)

With age, the endothelium cells ability to regenerate is greatly diminished, while there is increased cellular apoptosis (death) of endothelium.  The result is a shift from healthy vascular tissue to tissue which is unhealthy, taking on the characteristics of atherosclerotic tissue.

REFERENCES:

Pierce GL, et al. Nuclear factor{kappa}B activation contributes to vascular endothelial dysfunction via oxidative stress in overweight/obese middle-aged and older humans. Circulation. 2009 Mar 10;119(9):1284-92

Donato AJ, et al. Direct evidence of endothelial oxidative stress with aging in humans: relation to impaired endothelium-dependent dilation and upregulation of nuclear factor-kappaB. Circ Res. 2007 Jun 8;100(11):1659-66.

Mencarelli M, et al. Endothelin receptor A expression in human inflammatory cells. Regul Pept. 2009 Jun 11.

Donato AJ, et al. Vascular Endothelial Dysfunction with Aging: Endothelin-1 and Endothelial Nitric Oxide Synthase. Am J Physiol. 2009 May 22.

Yildiz O. Vascular smooth muscle and endothelial functions in aging. Ann NY Acad Sci. 2007 Apr;1100:353-60