Posts Tagged: circadian rhythm

Environmental Determinants of Cardiovascular Disease

Environmental Determinants of Cardiovascular Disease

Aruni Bhatnagar

The effect of sunlight on cardiovascular health. The visible range of sunlight regulates the master clock located in the pacemaker neurons of the suprachiasmatic nucleus, which sets the intrinsic 24-h cycle and synchronizes the light-insensitive peripheral clocks to coordinate cycles of waking, sleeping, and feeding. The UVB radiation converts 7-dehydrocholesterol in the epidermis to pre–vitamin D3, which undergoes thermal isomerization to vitamin D. Vitamin D3 formed in the skin appear in the circulation and is then transported to the liver where it is converted to 25(OH)D3. In kidney, 25(OH) D3 undergoes hydroxylation to form biologically active 1,25(OH)2D. The UVA radiation induces photodegradation of nitrosothiols, such as S-nitrosylglutathione, which leads to the generation of NO, an important regulator of blood pressure. (Illustration credit: Ben Smith.) [Powerpoint File]

Circadian Influence on Metabolism and Inflammation in Atherosclerosis

Circadian Influence on Metabolism and Inflammation in Atherosclerosis

Cameron S. McAlpine, Filip K. Swirski

Circadian influence on atherosclerosis. Circadian rhythms influence the supply of leukocytes and lipids in the circulation and the behavior of endothelial cells, smooth muscle cells, and macrophages in the vessel wall. Together, these systemic factors and local cellular events mediate atherosclerosis. HSC indicates hematopoietic stem cell. [Powerpoint File]