Cerebral blood flow in normal aging adults: cardiovascular determinants, clinical implications, and aerobic fitness

Abstract

Senescence is a leading cause of mortality, disability, and noncommunicable chronic diseases in older adults. Mounting evidence indicates that the presence of cardiovascular disease and risk factors elevates the incidence of both vascular cognitive impairment and Alzheimer's disease (AD). Age-related declines in cardiovascular function may impair cerebral blood flow (CBF) regulation, leading to the disruption of neuronal micro-environmental homeostasis. The brain is the most metabolically active organ with limited intracellular energy storage and critically depends on CBF to sustain neuronal metabolism. In patients with AD, cerebral hypoperfusion, increased CBF pulsatility, and impaired blood pressure control during orthostatic stress have been reported, indicating exaggerated, age-related decline in both cerebro-and cardiovascular function. Currently, AD lacks effective treatments; therefore, the development of preventive strategy is urgently needed. Regular aerobic exercise improves cardiovascular function, which in turn may lead to a better CBF regulation, thus reducing the dementia risk. In this review, we discuss the effects of aging on cardiovascular regulation of CBF and provide new insights into the vascular mechanisms of cognitive impairment and potential effects of aerobic exercise training on CBF regulation.

Current intensity‐ and polarity‐specific online and aftereffects of transcranial direct current stimulation: An fMRI study

“…Finally, regarding transferal of these findings, it is important to note that when considering the heterogenous spatial distribution of the arterial supply and vascular tone across the cortex (Fan, Jahanian, Holdsworth, & Zaharchuk, ), as well as spatial differences in neurotransmitter receptor densities (Zilles, Palomero‐Gallagher, & Schleicher, ), it is not self‐evident that the observed characteristics of the physiological effects observed by tDCS on the M1 will transfer one‐to‐one to other cortical regions, and further studies would be needed to test this assumption. Likewise, given the potential impact of the current results to clinical populations, the findings presented here in young healthy adults cannot be assumed to transfer one‐to‐one with patient brains, or older adults, where an age‐related reduction in steady‐state CBF and cerebral metabolic rate is well known (Tarumi & Zhang, ). Parallel investigations across these additional populations will thus be informative for determining the therapeutic efficacy of tDCS.…”

Sleep disordered breathing in children disrupts the maturation of autonomic control of heart rate and its association with cerebral oxygenation

“…We speculate that HRV parameters are predictive of cerebral oxygenation in non‐snoring controls during sleep but not in children with SDB, because HRV is dampened in children with SDB. We posit that the dominant role that the gradient between arterial BP and intracranial pressure has in cerebral blood flow (Tarumi & Zhang, ) may obfuscate the influence of HRV in children with SDB.…”

Dynamic cerebral autoregulation of endurance-trained men following 6 weeks of high-intensity interval training to exhaustion

“…Established evidence show that cardiorespiratory fitness (CRF) is more cardioprotective when compared to overall physical activity levels (19). CRF-related benefits are not confided to the cardiovascular function and rather extend to the cerebrovascular system (23,36). For instance, aerobic exercise training alters favorably cerebrovascular health in varying clinical conditions ranging from chronic obstructive pulmonary disease (21), cognitive impairments (6), stroke (14) and following cancer (27).…”