Food readjustment plus exercise training improves cardiovascular autonomic control and baroreflex sensitivity in high‐fat diet‐fed ovariectomized mice

Abstract

Despite consensus on the benefits of food readjustment and/or moderate‐intensity continuous exercise in the treatment of cardiometabolic risk factors, there is little evidence of the association between these two cardiovascular risk management strategies after menopause. Thus, the objective of this study was to evaluate the effects of food readjustment and/or exercise training on metabolic, hemodynamic, autonomic, and inflammatory parameters in a model of loss of ovarian function with diet‐induced obesity. Forty C57BL/6J ovariectomized mice were divided into the following groups: high‐fat diet‐fed ‐ 60% lipids throughout the protocol (HF), food readjustment ‐ 60% lipids for 5 weeks, readjusted to 10% for the next 5 weeks (FR), high‐fat diet‐fed undergoing moderate‐intensity exercise training (HFT), and food readjustment associated with moderate‐intensity exercise training (FRT). Blood glucose evaluations and oral glucose tolerance tests were performed. Blood pressure was assessed by direct intra‐arterial measurement. Baroreflex sensitivity was tested using heart rate phenylephrine and sodium nitroprusside induced blood pressure changes. Cardiovascular autonomic modulation was evaluated in time and frequency domains. Inflammatory profile was evaluated by IL‐6, IL‐10 cytokines, and TNF‐alpha measurements. Only the exercise training associated with food readjustment strategy induced improved functional capacity, body composition, metabolic parameters, inflammatory profile, and resting bradycardia, while positively changing cardiovascular autonomic modulation and increasing baroreflex sensitivity. Our findings demonstrate that the association of these strategies seems to be effective in the management of cardiometabolic risk in a model of loss of ovarian function with diet‐induced obesity.

Aerobic exercise attenuates dysautonomia, cardiac diastolic dysfunctions, and hemodynamic overload in female mice with atherosclerosis

“…Twenty-four hours after surgery, hemodynamic measurements were obtained, and the animals were awake and allowed to move freely in their cages. The cannula was coupled to a biological signal transducer for recording blood pressure signals (Blood Pressure XDCR, Kent Scientific, Litchfield, CT, USA) for 30 min using a digital converter (Windaq DI720, 4-kHz sampling frequency, Dataq Instruments) The recorded data were analyzed on a beat-to-beat basis to quantify changes in mean arterial pressure (MAP) and HR 24 , 25 .…”

“…For frequency domain analysis of cardiovascular autonomic modulation, PI and SAP were divided into segments and overlapped by 50%, cubic spline-decimated to be equally spaced in time after linear trend removal; power spectral density was obtained through the fast Fourier transformation. The components of spectral analysis were quantified in the very low-frequency ranges (VLF-PI, 0–0.4 Hz), low-frequency ranges (LF-PI, 0.4–1.5 Hz), and high-frequency ranges (HF-PI, 1.5–5.0 Hz) 25 , 26 .…”

“…or phenylephrine (8 μg/kg body wt i.v. ), respectively 15 , 25 . Maximal dose per injection was < 20 µg 15 , 25 .…”

“…), respectively 15 , 25 . Maximal dose per injection was < 20 µg 15 , 25 . Peak increases or decreases in MAP after phenylephrine or sodium nitroprusside injection and the corresponding peak reflex changes in HR were recorded for each drug dose.…”

Mitigation of Subsequent Ovariectomy Responses through Prior Exercise Training in Rats

“…Moreover, experimental studies have demonstrated that rats subjected to ovarian hormone deprivation due to OVX surgery present with increased blood pressure (BP), sympathetic tonus, oxidative stress, and body weight, and reduced baroreceptor reflex sensitivity (BRS) compared to control female rats. On the other hand, these studies showed that the exercise training (ET) recommended after OVX improved the cardiometabolic dysfunction [6,7].…”