Buss Caroline, Maranhão Priscila A, de Souza Maria das Graças C, Bouskela Eliete, Kraemer-Aguiar Luiz Guilherme
Department of Nutrition Federal University of Health Sciences of Porto Alegre (UFCSPA), RS, Brazil; Graduate Program in Health Sciences, UFCSPA, RS, Brazil.
Clinical and Experimental Research Laboratory on Vascular Biology (BioVasc) Biomedical Center, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Faculty of Medicine, Center for Research in Health Technologies and Information Systems (CINTESIS), University of Porto, Porto, Portugal.
Physiol Behav. 2020 Oct 15;225:113087. doi: 10.1016/j.physbeh.2020.113087. Epub 2020 Jul 22.
Neurally mediated anticipatory responses, also named cephalic-phase responses, and microcirculatory regulation are two important mechanisms to maintain metabolic homeostasis. Altered cephalic-phase responses in obesity and its metabolic consequences have been proposed. There is, however, a lack of studies focusing on in vivo assessment of the microcirculation during this phase in patients with obesity. In this randomized controlled trial, we selected patients with obesity and healthy subjects after clinical and laboratory assessments. Those with obesity were randomized into two groups: experimental (cephalic-phase microvascular response stimulation - CP group, n = 13) and controls (n = 14). Healthy subjects (n = 17) were also included to form a CP control group. Skin microvascular assessment was used as a model of systemic microcirculation. Resting functional capillary density (FCD) and peak FCD during post-occlusive reactive hyperemia (PORH) were measured by dorsal finger videocapillaroscopy and expressed mainly capillary recruitment capacity. Resting red blood cell velocity (RBCV), peak RBCV during PORH (RBCV), and time taken to reach RBCV (TRBCV) were assessed by dynamic nailfold videocapillaroscopy and expressed the microhemodynamics. Patients with obesity (with or without stimulus) failed to show an increase on FCD during PORH post-stimulus (p = 0.221 and p = 0.307, respectively) depicting lack of capillary recruitment. In contrast, healthy subjects presented an increase in this microvascular outcome (p = 0.004). Changes in all variables of microhemodynamics occurred in both CP groups (healthy and those with obesity). During CP, we originally demonstrated an absence of capillary recruitment in subjects with obesity. These findings might contribute to the literature of microvascular impairment and metabolic conditions.
神经介导的预期反应，也称为头期反应，以及微循环调节是维持代谢稳态的两个重要机制。肥胖症中头期反应的改变及其代谢后果已被提出。然而，缺乏针对肥胖患者在此阶段微循环的体内评估研究。在这项随机对照试验中，我们在临床和实验室评估后选择了肥胖患者和健康受试者。肥胖患者被随机分为两组：实验组（头期微血管反应刺激 - CP组，n = 13）和对照组（n = 14）。还纳入了健康受试者（n = 17）以形成CP对照组。皮肤微血管评估用作全身微循环的模型。通过手指背侧视频毛细血管镜测量静息功能毛细血管密度（FCD）和闭塞后反应性充血（PORH）期间的峰值FCD，主要表示毛细血管募集能力。通过动态甲襞视频毛细血管镜评估静息红细胞速度（RBCV）、PORH期间的峰值RBCV（RBCV）以及达到RBCV所需的时间（TRBCV），并表示微循环动力学。肥胖患者（有或无刺激）在刺激后PORH期间FCD未显示增加（分别为p = 0.221和p = 0.307），表明缺乏毛细血管募集。相比之下，健康受试者在这一微血管指标上有所增加（p = 0.004）。两个CP组（健康组和肥胖组）的微循环动力学所有变量均发生变化。在头期期间，我们最初证明肥胖受试者不存在毛细血管募集。这些发现可能有助于丰富微血管损伤和代谢状况的文献。
