Flow motion dynamics of microvascular blood flow and oxygenation: Evidence of adaptive changes in obesity and type 2 diabetes mellitus/insulin resistance

Abstract

An altered spatial heterogeneity and temporal stability of network perfusion can give rise to a limited adaptive ability to meet metabolic demands. Derangement of local flow motion activity is associated with reduced microvascular blood flow and tissue oxygenation, and it has been suggested that changes in flow motion activity may provide an early indicator of declining, endothelial, neurogenic, and myogenic regulatory mechanisms and signal the onset and progression of microvascular pathophysiology. This short conference review article explores some of the evidence for altered flow motion dynamics of blood flux signals acquired using laser Doppler fluximetry in the skin in individuals at risk of developing or with cardiometabolic disease.

Sustained vasomotor control of skin microcirculation in Sherpas versus altitude‐naive lowlanders: Experimental evidence from Xtreme Everest 2

“…This may be attributable to an adaptive modulation of sympathovagal activity through which Sherpas can better regulate flow, allowing them to stay in a hypobaric atmosphere at lower temperatures without excessive autonomic stress (Passino et al, 1996). Declining spontaneous variation in flowmotion activity may be deleterious to health and has been identified in cardiovascular and metabolic disease (Clough, Kuliga, & Chipperfield, 2017). Despite significant differences in microvascular flux and function, our data showed little distinction in forearm tissue oxygenation between the cohorts at high altitude.…”

“…In computational models, chaotic capillary activity has been shown to promote more efficient tissue oxygenation in skeletal muscle than regular rhythmic patterns of vasomotion (Pradhan et al 2007). Declining spontaneous variation in flowmotion activity may be deleterious to health and has been identified in cardiovascular and metabolic disease (Clough, Kuliga, & Chipperfield, 2017). Figure 1 demonstrates the changes in flowmotion control in both cohorts on ascent to altitude.…”

Multi‐domain analysis of microvascular flow motion dynamics in NAFLD

“…Spectral analysis of the frequency components of the LDF signal has been shown to reflect the influence of endothelial (0.0095‐0.02 Hz) and sympathetic (0.02‐0.06 Hz) activity, myogenic activity in the vessel wall (0.06‐0.15 Hz), respiration (0.15‐0.4 Hz), and heart beat (0.4‐1.6 Hz) on local tissue perfusion . Variations in the amplitude and relative contribution of the spontaneous, rhythmic oscillatory fluctuations of both local (endothelial, neurogenic, and myogenic) and systemic origin have been associated with a decline in microvascular function in individuals at risk of, or with CV and Met disease . However, time and frequency domain analysis have not proved sufficient for the classification of tissue perfusion features in different pathophysiological groups or provided consistent interpretation of microvascular function.…”

Time-dependent Behavior of Microvascular Blood Flow and Oxygenation: a Predictor of Functional Outcomes

“…Greater variability may also indicate an ability to influence flow independently of the spectral amplitude of flowmotion [16]. Thus a declining spontaneous variation in flowmotion activity as seen in vascular beds at risk of CV and Met disease [14] may contribute to a loss of system flexibility and adaptability in the face of physiological or pathological challenge.…”

“…Variations in the amplitude and relative contribution of these flowmotion oscillations have been associated with a decline in microvascular function in individuals at risk of CV and Met disease [9][10][11][12][13] (for review see [14]). Studies in a primate model of diabetes have shown a reduced complexity of the BF signal using a Lempel-Ziv (L-Z) complexity algorithm [15].…”