Retinal microvascular changes are known to be affected by inflammatory factors [26], and may be another biologic mechanism through which diet mediates microvascular caliber.

MLN8237 cell line Although the mechanisms underlying the above associations may not be completely understood, this data supports the vascular-protective effects of increased dietary fish, fiber, and low GI food consumption. Sedentary behavior, low levels of physical activity, and low cardiorespiratory fitness are all well-established risk factors for atherosclerosis and CVD [34]. Recent research has also shown that the adverse effects of lack of physical activity and low fitness extends to changes in microvascular structure [3,4,15,16,55]. Sedentary behavior, indicated by time spent watching TV and lower levels of physical activity, assessed via self-report, were found to be associated with retinal venular caliber [3,4,55], suggesting a possible deleterious

effect of decreased levels of physical activity and increased sedentary behavior on the microvasculature. In addition, the impact of physical activity on the retinal microvasculature was also observed in a cohort of 6-year children. In the study by Gopinath et al., children who spent more time in outdoor sporting activities had wider mean retinal arteriolar caliber [15], but those who spent more time watching TV had narrower mean retinal arteriolar Adriamycin mw caliber. More importantly, for each hour of daily television viewing time, oxyclozanide similar retinal arteriolar changes are associated with a 10 mmHg increase in systolic blood pressure [15]. Recently, there is also evidence showing the relationship between higher levels of physical fitness and retinal microvascular structure [16]. Higher cardiovascular fitness, as assessed by individual anaerobic threshold, was found to be related to retinal arteriolar dilation and higher retinal

AVR [16]. Moreover, 10 weeks of exercise training was also shown to induce arteriolar dilatation in obese individuals and increased AVR in both obese and lean individuals [16]. Conflicting results were found in a study of older women with type 2 diabetes in which no training-induced improvements in retinal vessel caliber were found after 12-weeks of moderate-intensity exercise. In this cohort, however, increased retinal microvascular density, shown by increased Df was associated with increased time to exhaustion during peak exercise testing, a measure of physical fitness. Observed associations between physical activity and changes in the retinal microvasculature may provide in vivo evidence regarding the effect of physical activity on the systemic circulation. Although the exact pathophysiologic mechanisms behind these relationships is not know, recent research suggests that moderators of vascular tone, specifically NO and ADMA, may play a significant role.