Endotheliumprotectiv and antihypoxic properties of quercetin in elderly patients with metabolic syndrome

Abstract

Aim: To investigate the effectiveness of course quercetin in improving functional state of the microvascular endothelium and to determine the possibility of using quercetin to increase body resistance to hypoxia in the elderly. Materials and methods. The effectiveness of quercetin in improving the functional state of the endothelium and increasing body resistance to hypoxia was studied in 110 elderly patients with metabolic syndrome, who were divided equally into the main and control groups. Patients in the main group received quercetin at a daily dose of 240 mg for 3 months, and patients in the control group received placebo for the same period. Before and after treatment, the microvascular endothelial function was studied by laser Doppler flowmetry using the post-occlusive hyperemia test. Acute hypoxic test was performed under isocapnicnormobaric hypoxia, during which the followings were recorded: blood saturation (SpO2), heart rate and diastolic blood pressure (BP). Results. In the group of patients receiving quercetin, there was an improvement in blood flow to the skin, as evidenced by a statistically significant increase in the maximum volumetric rate of cutaneous blood flow and the duration of the recovery period of OSHSK to baseline in the post-occlusive hyperaemia. The course of quercetin also led to a less significant decrease in SpO2 during hypoxic test and to a decrease in the absolute values of systolic and diastolic blood pressure, while reducing an increase of the systolic blood pressure on the 20th min of the hypoxic test. Conclusions. In elderly patients with metabolic syndrome (within a 3 month course) the use of quercetin has improved the microvascular endothelium functional status and increased the resistance to hypoxia.