Resistance or aerobic training decreases blood pressure and improves cardiovascular autonomic control and oxidative stress in hypertensive menopausal rats

Mitigation of Subsequent Ovariectomy Responses through Prior Exercise Training in Rats

It is well known that cardiometabolic dysfunction gradually increases after menopause, and the sedentary lifestyle can aggravate this condition. Therefore, we compared the effects of aerobic exercise training during the premenopausal period and after ovariectomy (OVX) on metabolic, hemodynamic, and autonomic parameters in an experimental rat model of menopause. The female rats were divided into four groups: control (C), sedentary OVX (SO), trained OVX (TO), and previously trained OVX (PTO). The PTO group was trained for 4 weeks prior to+8 weeks after OVX, and the TO group trained only after OVX on a motor treadmill. Autonomic modulation was evaluated, white adipose tissue (WAT) was removed and weighed, and lipolysis was assessed. The citrate synthase activity in the soleus muscle was analyzed. The trained groups prevented the impairment of baroreceptor reflex sensitivity in relation to SO; however, only PTO reduced the low-frequency band of the pulse interval compared to SO. PTO reduced the weight of WAT compared to the other groups; lipolysis in PTO was similar to that in C. PTO preserved muscle metabolic injury in all types of fibers analyzed. In conclusion, this study suggests that exercise training should be recommended in a premenopausal model to prevent cardiometabolic and autonomic menopause-induced deleterious effects.

Combined cardiovascular effects of ovariectomy and high-intensity interval training in female spontaneously hypertensive rats

Hypertensive postmenopausal women are more likely to develop adverse cardiac remodeling and respond less effectively to drug treatment than men. High-intensity interval exercise (HIIE) is a nonpharmacological strategy for the treatment of hypertension; however, the effectiveness in women remains uncertain. This study was designed to evaluate 1) the effects of HIIE training upon morphological and functional markers of cardiovascular health in female SHR and 2) to determine whether the hormonal shift induced by ovariectomy could influence cardiovascular responses to HIIE. Thirty-six SHR were randomly assigned to four groups: ovariectomized sedentary, ovariectomized trained, sham-operated sedentary, and sham-operated trained. The trained rats performed HIIE 5 days/wk for 8 wk. Blood pressure and echocardiographic measurements were performed before and after training in animals. Cardiac response to β-adrenergic stimulation and the expression of calcium regulatory proteins and estrogen receptors in heart samples were assessed. Endothelium-dependent vasorelaxation in response to acetylcholine was evaluated in aortic rings as well as the expression of nitric oxide synthase isoforms (eNOS and P-eNOS) by Western blotting. In both groups of trained SHR, HIIE induced eccentric cardiac remodeling with greater inotropic and chronotropic effects, as well as an increase in SERCA and β1AR expression. However, although the trained rats showed improved endothelial function and expression of eNOS and P-eNOS in the aorta, there was no demonstrated effect on blood pressure. In addition, the responses to HIIE training were not affected by ovariectomy. This work highlights the importance of assessing the cardiovascular efficacy and safety of different exercise modalities in women.NEW & NOTEWORTHY This study reports the effects of high-intensity interval exercise (HIIE) training on cardiac and endothelial function in female hypertensive rats. Despite a lack of effect on blood pressure (BP), HIIE training induces eccentric cardiac remodeling with greater functionals effects. Furthermore, training has beneficial effects on endothelial function. However, ovarian hormones do not seem to modulate cardiac and aortic adaptations to this training modality. All this underlines the need to consider training modalities on the cardiovascular system in women.

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

Cardiovascular risk increases during the aging process in women with atherosclerosis and exercise training is a strategy for management of cardiac risks in at-risk populations. Therefore, the aims of this study were to evaluate: (1) the influence of the aging process on cardiac function, hemodynamics, cardiovascular autonomic modulation, and baroreflex sensitivity in females with atherosclerosis at the onset of reproductive senescence; and (2) the impact of exercise training on age-related dysfunctions in this model. Eighteen Apolipoprotein-E knockout female mice were divided equally into young (Y), middle-aged (MA), and trained middle-aged (MAT). Echocardiographic exams were performed to verify cardiac morphology and function. Cannulation for direct recording of blood pressure and heart rate, and analysis of cardiovascular autonomic modulation, baroreflex sensitivity were performed. The MA had lower cardiac diastolic function (E'/A' ratio), and higher aortic thickness, heart rate and mean arterial pressure, lower heart rate variability and baroreflex sensitivity compared with Y. There were no differences between Y and MAT in these parameters. Positive correlation coefficients were found between aortic wall thickness with hemodynamics data. The aging process causes a series of deleterious effects such as hemodynamic overload and dysautonomia in female with atherosclerosis. Exercise training was effective in mitigating aged-related dysfunctions.

Concurrent exercise training potentiates the effects of angiotensin-converting enzyme inhibitor on regulatory systems of blood pressure control in ovariectomized hypertensive rats

OBJECTIVE

Enalapril has shown satisfactory potential in controlling increased and sustained blood pressure (BP). However, multiple dysregulated mechanisms that interact with each other and are involved in the pathophysiology of arterial hypertension may not be affected, contributing to the remaining cardiovascular risk. Using an exercise training protocol, we investigated whether adding both approaches to arterial hypertension management could promote higher modulation of regulatory mechanisms of BP in postmenopausal rats.

METHODS

Spontaneously hypertensive rats were allocated into sedentary (S) and ovariectomized groups: sedentary (OS), sedentary treated with enalapril maleate (OSE) and trained treated with enalapril maleate (OTE). Both the pharmacological and exercise training protocols lasted for 8 weeks. The BP was directly recorded. Inflammation and oxidative stress were evaluated in the cardiac tissue.

RESULTS

Although BP reduction was similar between OSE and OTE, trained group showed lower vasopressor systems outflow after sympathetic ganglion blocking by hexamethonium (mean BP) (OTE: -53.7 ± 9.86 vs. OS: -75.7 ± 19.2 mmHg). Bradycardic and tachycardic response were increased in OTE group (-1.4 ± 0.4 and -2.6 ± 0.4 vs. OS: -0.6 ± 0.3 and -1.3 ± 0.4 bpm/mmHg, respectively), as well as BP variability. In addition, the combination of approaches induced an increase in interleukin 10, antioxidant defense (catalase and glutathione peroxidase) and nitrite levels compared with the OS group.

CONCLUSION

Despite similar BP, the inclusion of exercise training in antihypertensive drug treatment exacerbates the positive adaptations induced by enalapril alone on autonomic, inflammatory and oxidative stress profiles, probably affecting end-organ damage and remaining risk.

Impact of exercise training associated with enalapril treatment on blood pressure variability and renal dysfunctions in an experimental model of arterial hypertension and postmenopause

OBJECTIVE

In this study, we aimed to investigate the effects of the concurrent exercise training (CET) associated with the enalapril maleate on blood pressure variability (BPV) and renal profile in an experimental model of arterial hypertension (AH) and postmenopause.

METHODS

Female ovariectomized spontaneously hypertensive rats (SHR) were distributed into 4 groups (n = 8/group): sedentary (SO), sedentary + enalapril (SOE), trained (TO) and trained + enalapril (TOE). Both enalapril (3mg/kg) and CET (3 days/week) were conducted during 8 weeks. Blood pressure (BP) was directly recorded for BPV analyses. Renal function, morphology, inflammation and oxidative stress were assessed.

RESULTS

The SOE, TO e TOE groups presented decreased systolic BP compared with SO. Both trained groups (TO and TOE) presented lower BPV and increased baroreflex sensitivity (TO: 0.76 ± 0.20 and TOE: 1.02 ± 0.40 vs. SO: 0.40 ± 0.07 ms/mmHg) compared with SO group, with additional improvements in TOE group. Creatinine and IL-6 levels were reduced in SOE, TO and TOE compared with SO group, while IL-10 was increased only in TOE group (vs. SO). Enalapril combined with CET promote reduction in lipoperoxidation (TOE: 1.37 ± 0.26 vs. SO: 2.08 ± 0.48 and SOE: 1.84 ± 0.35 μmol/mg protein) and hydrogen peroxide (TOE: 1.89 ± 0.40 vs. SO: 3.70 ± 0.19 and SOE: 2.73 ± 0.70 μM), as well as increase in catalase activity (vs. sedentary groups). The tubulointerstitial injury was lower in interventions groups (SOE, TO and TOE vs. SO), with potentialized benefits in the trained groups.

CONCLUSIONS

Enalapril combined with CET attenuated BPV and baroreflex dysfunctions, probably impacting on end-organ damage, as demonstrated by attenuation in the AH-induced renal inflammations, oxidative stress and morphofunctional impairments in postmenopausal rats.

Concurrent exercise training induces additional benefits to hydrochlorothiazide: Evidence for an improvement of autonomic control and oxidative stress in a model of hypertension and postmenopause

OBJECTIVE

This study aimed to evaluate whether exercise training could contribute to a better modulation of the neurohumoral mechanisms linked to the pathophysiology of arterial hypertension (AH) in postmenopausal hypertensive rats treated with hydrochlorothiazide (HCTZ).

METHODS

Female spontaneously hypertensive rats (SHR) (150-200g, 90 days old) were distributed into 5 hypertensive groups (n = 7-8 rats/group): control (C), ovariectomized (O), ovariectomized treated with HCTZ (OH), ovariectomized submitted to exercise training (OT) and ovariectomized submitted to exercise training and treated with HCTZ (OTH). Ovarian hormone deprivation was performed through bilateral ovariectomy. HCTZ (30mg/kg/day) and concurrent exercise training (3d/wk) were conducted lasted 8 weeks. Arterial pressure (AP) was directly recorded. Cardiac effort was evaluated using the rate-pressure product (RPP = systolic AP x heart rate). Vasopressin V1 receptor antagonist, losartan and hexamethonium were sequentially injected to evaluate the vasopressor systems. Inflammation and oxidative stress were evaluated in cardiac tissue.

RESULTS

In addition to the reduction in AP, trained groups improved RPP, AP variability, bradycardic (OT: -1.3 ± 0.4 and OTH: -1.6 ± 0.3 vs. O: -0.6 ± 0.3 bpm/mmHg) and tachycardic responses of baroreflex sensitivity (OT: -2.4 ± 0.8 and OTH: -2.4 ± 0.8 vs. O: -1.3 ± 0.5 bpm/mmHg), NADPH oxidase and IL-10/TNF-α ratio. Hexamethonium injection revealed reduced sympathetic contribution on basal AP in OTH group (OTH: -49.8 ± 12.4 vs. O: -74.6 ± 18.1 mmHg). Furthermore, cardiac sympathovagal balance (LF/HF ratio), IL-10 and antioxidant enzymes were enhanced in OTH group. AP variability and baroreflex sensitivity were correlated with systolic AP, RPP, LF/HF ratio and inflammatory and oxidative stress parameters.

CONCLUSION

The combination of HCTZ plus concurrent exercise training induced additional positive adaptations in cardiovascular autonomic control, inflammation and redox balance in ovariectomized SHR. Therefore, combining exercise and medication may represent a promising strategy for managing classic and remaining cardiovascular risks in AH.

Hypertension after the Menopause: What Can We Learn from Experimental Studies?

Hypertension is the most prevalent cardiovascular disease of the adult population and is closely associated with serious cardiovascular events. The burden of hypertension with respect to vascular and other organ damage is greater in women. These sex differences are not fully understood. The unique feature in women is their transition to menopause accompanied by profound hormonal changes that affect the vasculature that are also associated with changes of blood pressure. Results from studies of hormone replacement therapy and its effects on the cardiovascular system are controversial, and the timing of treatment after menopause seems to be important. Therefore, revealing potential sex- and sex hormone-dependent pathophysiological mechanisms of hypertension in experimental studies could provide valuable information for better treatment of hypertension and vascular impairment, especially in postmenopausal women. The experimental rat models subjected to ovariectomy mimicking menopause could be useful tools for studying the mechanisms of blood pressure regulation after menopause and during subsequent therapy.

Combined Exercise Training Promotes More Benefits on Cardiovascular Autonomic Modulation in Ovariectomized Rats Than Isolated Aerobic or Resistance Training

Introduction

Cardiovascular risk increase after ovarian deprivation has been extensively demonstrated by our research group through cardiovascular autonomic analysis. Interventions involving different types of exercises, such as resistance exercises or combined exercises (aerobic and resistance) have been widely recommended to prevent or minimize neuromuscular decline in postmenopausal women, which is aggravated by a sedentary lifestyle. Experimentally, the cardiovascular effects of resistance or combined training, as well as comparison between aerobic, resistance, and combined training, in ovariectomized animals are scarce.

Purpose

In this study, we hypothesized that the combination of aerobic and resistance training may be more effective in preventing muscle mass loss, as well as improving cardiovascular autonomic modulation and baroreflex sensitivity, than aerobic or resistance training individually in ovariectomized rats.

Animals and Methods

Female rats were divided into 5 groups: sedentary (C); ovariectomized (Ovx); trained ovariectomized submitted to aerobic training (OvxAT); resistance training (OvxRT); combined training (OvxCT). Exercise training lasted 8 weeks, with the combined group alternating between aerobic training and resistance training every other day. At the end of the study, glycemia and insulin tolerance were evaluated. Arterial pressure (AP) was directly recorded. Baroreflex sensitivity was assessed by heart rate response to changes in arterial pressure. Cardiovascular autonomic modulation was evaluated by spectral analysis.

Results

Combined training was the only training regime that increased baroreflex sensitivity for tachycardic response and reduced all systolic blood pressure variability parameters. Furthermore, all animals submitted to exercise training on a treadmill (OvxAT and OvxCT) presented lower systolic, diastolic, and mean pressure, as well as improvements in the autonomic modulation for the heart.

Conclusion

Combined training showed to be more effective than isolated aerobic and resistance training, mixing the isolated benefits of each modality. It was the only modality able to increase baroreflex sensitivity to tachycardic responses, reduce arterial pressure and all parameters of vascular sympathetic modulation.

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

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.

Effect of exercise and antioxidant supplementation on cellular lipid peroxidation in elderly individuals: Systematic review and network meta-analysis

Background: The viewpoints of previous studies on the correlation between exercise and cellular lipid peroxidation are contradictory from many perspectives and lack evidence for elder individuals. A new systematic review with network meta-analysis is necessary and will have significant practical value to provide high-quality evidence in the development of exercise protocols and an evidence-based guide for antioxidant supplementation for the elderly. Aims: To identify the cellular lipid peroxidation induced by different types of exercise, with or without antioxidant supplementation, in elderly individuals. Methods: Randomized controlled trials that recruited elderly participants and reported cellular lipid peroxidation indicators and were published in peer-reviewed journals in English were searched by a Boolean logic search strategy and screened in the databases PubMed, Medline, Embase, and Web of Science. The outcome measures were the biomarkers of oxidative stress in cell lipids in urine and blood, namely F2-isoprostanes, hydrogen peroxide (LOOH, PEROX, or LIPOX), malondialdehyde (MDA), and thiobarbituric acid reactive substances (TBARS). Result: 7 trials were included. A combination program of aerobic exercise (AE), low-intensity resistance training (LIRT), and a placebo intake (Placebo) and a combination program of aerobic exercise, low-intensity resistance training, and antioxidant supplementation (S) had the most and sub-most potential to dampen cellular lipid peroxidation (AE + LIRT + Placebo: 0.31 in Rank 1 and 0.2 in Rank 2; AE + LIRT + S: 0.19 in Rank 1 and 0.20 in Rank 2); A placebo intake (Placebo) and a blank intervention without exercise (NE) had the most and sub-most potential to induce an enhancement of cellular lipid peroxidation (Placebo: 0.51 in Rank 9 and 0.16 in Rank 8; NE: 0.16 in Rank 9 and 0.28 in Rank 8). All included studies had an unclear risk of selecting reporting. There were no high confidence ratings in all the direct and indirect comparisons, 4 comparisons in the direct evidence structure and 7 comparisons in the indirect evidence structure had moderate confidence. Conclusion: A combined protocol consisting of aerobic exercise and low-intensity resistance training is recommended to dampen cellular lipid peroxidation. Extra antioxidant supplementation might be unnecessary if an elderly individual has enough aerobic and resistance exercise. Systematic Review Registration: CRD42022367430.

Physical Exercise Effects on Cardiovascular Autonomic Modulation in Postmenopausal Women-A Systematic Review and Meta-Analysis

BACKGROUND

The cardioprotective effect of physical exercise has been demonstrated in several studies. However, no systematic or updated analysis has described the effects of physical exercise on cardiovascular autonomic modulation in postmenopausal women.

AIM

to describe the effects of physical exercise on cardiovascular autonomic modulation in postmenopausal women.

METHODS

The Scopus, PubMed, and Embase databases were searched for randomized clinical trials published between January 2011 and December 2021, and regarding the effects of physical exercise on cardiovascular autonomic modulation in postmenopausal women. Two independent authors processed the citations. The methodological quality was evaluated using the PEDRo scale.

RESULTS

Of the 91 studies identified, only 8 met the inclusion criteria, of which 7 had fair or poor methodological quality. The analyzed studies investigated the effects of functional training, whole-body vibration, muscular resistance, stretching, and aerobic exercises performed at home or at the gym. The majority of these exercise modalities showed improvements in heart-rate variability (HRV) indices and in the low-frequency band of blood pressure variability. The meta-analysis shows that exercise increased the standard deviation of instantaneous beat-to-beat variability (SD1) (mean difference (MD) = 3.99; 95% confidence interval (CI) = 1.22 to 6.77, n = 46; I²: 0%) and the standard deviation of long-term variability (SD2) (MD = 11.37; 95% CI = 2.99 to 19.75; n = 46; I²: 0%).

CONCLUSIONS

Aerobic exercise and some nonconventional training modalities may have beneficial effects on cardiovascular autonomic modulation in postmenopausal women. More high-quality studies are still needed to further confirm their efficacy and safety.

Cardiac changes in spontaneously hypertensive rats: Modulation by aerobic exercise

Systemic arterial hypertension is a multifactorial clinical condition characterized by high and sustained levels of blood pressure. For a better understanding of the pathophysiology of hypertension, studies are conducted with spontaneously hypertensive animals, which allow the investigation of physiological changes that in most cases cannot be studied in humans. In these animals, myocardial remodeling, increased pro-inflammatory markers, redox imbalance and contractile dysfunctions that lead to changes in cardiac function can be observed. However, it can be inferring that aerobic training improves cardiac function and cardiomyocyte contractility, in addition to controlling inflammation and reducing oxidative stress in cardiac muscle, despite this, the precise mechanisms by which physical exercise improves cardiovascular control are not fully understood. In this review, we provide an overview of the pathophysiological changes that affect the heart of spontaneously hypertensive animals and their modulation by aerobic exercise.

Combined effect of physical exercise and hormone replacement therapy on cardiovascular and metabolic health in postmenopausal women: A systematic review and meta-analysis

The cardioprotective effect of postmenopausal hormone replacement therapy (HRT) has been demonstrated in several studies. Similarly, physical exercise has yielded positive results. However, the effects of their combination remain inconclusive. This review describes the combined effects of physical exercise and hormone therapy on cardiovascular and metabolic health in postmenopausal women. We searched the Scopus, Web of Science, PubMed, and Embase databases and included randomized controlled trials published up to December 2021 on the combined effects of physical exercise and hormone therapy on cardiovascular and metabolic health in postmenopausal women. We identified 148 articles, of which only seven met the inclusion criteria (386 participants; 91 [23%] HRT + exercise; 104 [27%] HRT; 103 [27%] exercise; 88 [23%] placebo). The combined treatment further decreased systolic blood pressure (SBP) compared to the isolated effect of aerobic training (AT) (mean difference [MD]=-1.69; 95% confidence interval [CI]=-2.65 to -0.72, n=73). Nevertheless, it attenuated the decrease in diastolic blood pressure (DBP) (MD=0.78; 95%CI: 0.22-1.35, n=73), and the increase in peak oxygen consumption (VO2 peak) promoted by exercise (AT + HRT=2.8±1.4 vs AT + placebo=5.8±3.4, P=0.02). The combination of AT and oral HRT improved SBP. However, AT alone seemed to have a better effect on physical fitness and DBP in postmenopausal women.

Elastic resistance training is more effective than vitamin D3 supplementation in reducing oxidative stress and strengthen antioxidant enzymes in healthy men

OBJECTIVE

Today, reducing oxidative stress and improving the antioxidant system with antioxidant supplements along with exercise training has received a lot of attention. Vitamin D plays a very important role in general health and reducing oxidative stress. The aim of this study was to examine the effect of vitamin D3 supplements during elastic-band resistance training (EBT) on oxidative stress and antioxidant indices in healthy men.

METHODS

Forty healthy men (Serum: 20 ≤ 25 (OH) D ≤ 25 ng/mL) voluntarily participated in the current study and randomly were assigned to EBT-vitamin D3 (ED, n = 10), EBT-placebo (EP, n = 10), vitamin D3 (VD, n = 10), and control (Con, n = 10). EBT was performed three times per week on non-consecutive days for eight weeks, in seven exercises. The subjects in the ED, VD, and EP consumed 50,000 IU vitamin D3 or placebo once every 2 weeks. Ten ccs blood samples were collected before and after exercise training and the total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPX), and creatine kinase (CK) activities were measured in the plasma. Malondialdehyde (MDA), as the lipid peroxidation index, and 25(OH) D were measured in the plasma.

RESULTS

We found that there was a significant difference between ED with VD (p = 0.011) and Con (p = 0.022) for MDA. A significant difference was also seen for SOD in ED with VD (p = 0.024) and Con (p = 0.038) and TAC in ED with VD (p = 0.020) and Con (p = 0.030), and GPX in ED with VD (p = 0.040) and Con (p = 0.010). While there were no significant differences between ED and EP in all mentioned variables (p > 0.05).

CONCLUSION

Finally, it can be said that elastic resistance training improved antioxidant defence. However, vitamin D3 supplementation during resistance elastic training has no synergistic effect on attenuating oxidative stress indices.

Effect of combined aerobic and resistance exercise on blood pressure in postmenopausal women: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The purpose of this study is to evaluate the effects of combined aerobic and resistance exercise on blood pressure (BP) in postmenopausal women. The results of this study will provide an effective means for postmenopausal women to control BP and reduce the morbidity and mortality of cardiovascular disease (CVD).

METHODS

Eligible studies were searched in five electronic databases until November 2020, and 11 randomized controlled trials that met the inclusion criteria were included in this systematic review and meta-analysis. The random-effects model was used to calculate overall effect sizes of weighted mean differences (WMD) and 95% confidence interval (CI). This study was registered in PROSPERO with the registration number: CRD42021225546.

RESULTS

Compared with the control group, the aerobic combined resistance exercise significantly decreased the systolic blood pressure (SBP) and diastolic blood pressure (DBP) by 0.81 mmHg (95% CI, -1.34 to -0.28) and 0.62 mmHg (95% CI, -1.11 to -0.14), respectively. The results of the meta-analysis also indicated that a significant reduction in brachial-to-ankle pulse wave velocity (baPWV) of - 1.18 m/s (95% CI, -1.81 to -0.56) and heart rate (HR) of -0.22 beats/min (95% CI: -0.42 to -0.02) after combined aerobic and resistance exercise intervention. Subgroup analysis showed that postmenopausal women ≥60 years of age who were overweight or had a normal baseline BP were more sensitive to the combined aerobic and resistance exercise. When combined aerobic and resistance exercise frequency < 3 times/week, weekly exercise time ≥ 150 min, or the duration of exercise lasted for 12 weeks, the SBP and DBP of postmenopausal women could be reduced more effectively.

CONCLUSIONS

The present study indicates that combined aerobic and resistance exercise can significantly reduce BP in postmenopausal women. Accordingly, combined aerobic and resistance exercise may be an effective way to prevent and manage hypertension in postmenopausal women.

Nicotinamide attenuates streptozotocin-induced diabetes complications and increases survival rate in rats: role of autonomic nervous system

BACKGROUND

To evaluate the effect of nicotinamide prior to streptozotocin-induced (STZ) diabetes in baroreflex sensitivity and cardiovascular autonomic modulation, and its association with hemodynamics and metabolic parameters.

METHODS

Methods: Male Wistar rats were divided into control (Cont) and STZ-induced diabetes (Diab). Half of the rats from each group received a single dose of nicotinamide (100 mg/Kg) before STZ injection (Cont+NicA and Diab+NicA). All groups were followed-up for 5 weeks.

RESULTS

Body weight loss of more than 40% was observed in Diab throughout the period (Diab: 271.00 ± 12.74 g; Diab+NicA: 344.62 ± 17.82). Increased glycemia was seen in Diab rats (541.28 ± 18.68 mg/dl) while Diab+NicA group had a slight decrease (440.87 ± 20.96 mg/dl). However, insulin resistance was observed only in Diab. In relation to Cont, heart rate, mean blood pressure and diastolic function were reduced when compared to Diab, together with parasympathetic modulation and baroreflex sensitivity. All of these parameters were improved in Diab+NicA when compared to Diab. Improved baroreflex sensitivity and parasympathetic modulation were correlated with glycemia, insulin resistance, and body weight mass. Additionally, Diab+NicA group increased survival rate.

CONCLUSIONS

Results suggest that the association of nicotinamide in STZ-induced diabetic rats prevents most of the expected derangements mainly by preserving parasympathetic and baroreflex parameters.

Aerobic Exercise During Advance Stage of Uncontrolled Arterial Hypertension

Aim

To evaluate the influence of physical training on myocardial function, oxidative stress, energy metabolism, and MAPKs and NF-κB signaling pathways in spontaneously hypertensive rats (SHR), at advanced stage of arterial hypertension, which precedes heart failure development.

Methods

We studied four experimental groups: normotensive Wistar rats (W, n = 27), trained W (W-EX, n = 31), SHR (n = 27), and exercised SHR (SHR-EX, n = 32). At 13 months old, the exercise groups underwent treadmill exercise 5 days a week for 4 months. In vitro myocardial function was analyzed in left ventricular (LV) papillary muscle preparations. Antioxidant enzyme activity and energy metabolism were assessed by spectrophotometry. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was analyzed by lucigenin reduction and protein expression by Western blot. Statistical analyzes: ANOVA and Tukey or Kruskal–Wallis and Dunn tests.

Results

SHR-EX had a lower frequency of heart failure features than SHR. Myocardial function and antioxidant enzyme activity were better in SHR-EX than SHR. Lipid hydroperoxide concentration, and phosphorylated JNK and total IkB protein expression were higher in hypertensive than control groups. Malondialdehyde, NADPH oxidase activity, total JNK, phosphorylated p38, phosphorylated and total p65 NF-κB, and phosphorylated IkB did not differ between groups. Protein expression from total p38, and total and phosphorylated ERK were higher in SHR than W. Lactate dehydrogenase and phosphorylated ERK were lower and citrate synthase and β-hydroxyacyldehydrogenase were higher in SHR-EX than SHR.

Conclusion

Exercise improves physical capacity, myocardial function, and antioxidant enzyme activity; reduces the frequency of heart failure features and ERK phosphorylation; and normalizes energy metabolism in SHR.

Resistance training improves cardiac function and cardiovascular autonomic control in doxorubicin-induced cardiotoxicity

Doxorubicin (DOX) is an anticancer chemotherapy drug that is widely used in clinical practice. It is well documented that DOX impairs baroreflex responsiveness and left ventricular function and enhances sympathetic activity, cardiac sympathetic afferent reflexes and oxidative stress, which contribute to hemodynamic deterioration. Because resistance training (RT)-induced cardioprotection has been observed in other animal models, the objective of this study was to assess the effects of RT during DOX treatment on hemodynamics, arterial baroreflex, cardiac autonomic tone, left ventricular function and oxidative stress in rats with DOX-induced cardiotoxicity. Male Wistar rats were submitted to a RT protocol (3 sets of 10 repetitions, 40% of one-repetition maximum (1RM) of intensity, 3 times per week, for 8 weeks). The rats were separated into 3 groups: sedentary control, DOX sedentary (2.5 mg/kg of DOX intraperitoneal injection, once a week, for 6 weeks) and DOX + RT. After training or time control, the animals were anesthetized and 2 catheters were implanted for hemodynamic, arterial baroreflex and cardiac autonomic tone. Another group of animals was used to evaluate left ventricular function. We found that RT in DOX-treated rats decreased diastolic arterial pressure, heart rate, sympathetic tone and oxidative stress. In addition, RT increased arterial baroreflex sensitivity, vagal tone and left ventricular developed pressure in rats with DOX-induced cardiotoxicity. In summary, RT is a useful non-pharmacological strategy to attenuate DOX-induced cardiotoxicity.

Estrogen Deprivation and Myocardial Infarction: Role of Aerobic Exercise Training, Inflammation and Metabolomics

In general, postmenopausal women present higher mortality, and worse prognosis after myocardial infarction (MI) compared to men, due to estrogen deficiency. After MI, cardiovascular alterations occur such as the autonomic imbalance and the pro-inflammatory cytokines increase. In this sense, therapies that aim to minimize deleterious effects caused by myocardial ischemia are important. Aerobic training has been proposed as a promising intervention in the prevention of cardiovascular diseases. On the other hand, some studies have attempted to identify potential biomarkers for cardiovascular diseases or specifically for MI. For this purpose, metabolomics has been used as a tool in the discovery of cardiovascular biomarkers. Therefore, the objective of this work is to discuss the changes involved in ovariectomy, myocardial infarction, and aerobic training, with emphasis on inflammation and metabolism.

Aerobic or resistance training improves autonomic control of circulation in oophorectomized rats with cardiometabolic dysfunctions: Impact on renal oxidative stress

Cardiovascular autonomic dysfunction is associated with end organ damage and increased risk of mortality. Menopause and metabolic syndrome increase the risk for cardiorenal complications. In this study, we investigated the effects of aerobic or resistance exercise training on autonomic control of circulation and renal oxidative stress in a model of menopause and metabolic syndrome. Female Wistar rats and spontaneously hypertensive rats (SHR) were divided into 5 groups (n = 8): control (C), hypertensive (H), and sedentary (FHO), aerobic trained (FHOTa) and resistance trained (FHOTr) oophorectomized hypertensive treated with fructose (100 mg/mL drink water for 19 weeks). The FHO group presented increased vascular sympathetic modulation (LF-SBP), impaired baroreflex sensitivity (BRS) associated with increased blood pressure (BP) when compared to the H group. Aerobic exercise training enhanced tachycardic responses, while resistance training improved bradycardic responses to BP changes, thus ameliorating BRS. Moreover, despite unchanged BP, both exercise training protocols were effective in preventing increase in LF-SBP, reduction in systemic nitric oxide bioavailability (NOx), and increase in oxidative stress in the renal tissue, by decreasing lipid and protein oxidation in renal tissue. Positive correlation between LF-SBP and renal lipoperoxidation (r = 0.63, p < 0.05), as well as a negative correlation between NOx and renal lipoperoxidation (r = -0.66, p < 0.05) were observed. In conclusion, both aerobic and resistance exercise training were effective in improving autonomic control of circulation and reducing renal oxidative stress, thus attenuating the deleterious effects induced by arterial hypertension and fructose overload in female rats after ovarian hormone deprivation.

Impact of combined exercise training on the development of cardiometabolic and neuroimmune complications induced by fructose consumption in hypertensive rats

This study evaluated the impact of combined exercise training on the development of cardiovascular and neuroimmune complications induced by fructose consumption (10% in the drinking water) in hypertensive rats (SHR). After weaning, SHR were divided into 3 groups: SHR (H), SHR+fructose (HF) and SHR+fructose+combined exercise training (treadmill+ladder, 40-60% of maximum capacity) (HFTC). Metabolic, hemodynamic, autonomic, inflammatory and oxidative stress parameters were evaluated in the subgroups (n = 6 group/time) at 7, 15, 30 and 60 days of protocol. Fructose consumption (H vs. HF groups) decreased spontaneous baroreflex sensitivity and total variance of pulse interval at day 7 (7 to 60); increased IL-6 and TNFα in the heart (at day 15, 30 and 60) and NADPH oxidase activity and cardiac lipoperoxidation (LPO) (day 60); increased white adipose tissue weight, reduced insulin sensitivity and increased triglycerides (day 60); induced an additional increase in mean arterial pressure (MAP) (days 30 and 60). Combined exercise training prevented such dysfunctions and sustained increased cardiac IL-10 (day 7) and glutathione redox balance (GSH/GSSG) for the entire protocol. In conclusion, combined exercise training performed simultaneously with exacerbated fructose consumption prevented early cardiovascular autonomic dysfunction, probably trigging positive changes in inflammation and oxidative stress, resulting in a better cardiometabolic profile in rats genetically predisposed to hypertension.

Short-Term Resistance Training Improves Cardiac Autonomic Modulation and Blood Pressure in Hypertensive Older Women: A Randomized Controlled Trial

Oliveira-Dantas, FF, Brasileiro-Santos, MdS, Thomas, SG, Silva, AS, Silva, DC, Browne, RAV, Farias-Junior, LF, Costa, EC, and Santos, AdC. Short-term resistance training improves cardiac autonomic modulation and blood pressure in hypertensive older women: a randomized controlled trial. J Strength Cond Res 34(1): 37-45, 2020-This randomized controlled trial investigated the efficacy of short-term resistance training (RT) on cardiac autonomic modulation and peripheral hemodynamic parameters in hypertensive older women. Twenty-five hypertensive older women who were insufficiently active (64.7 ± 4.7 years) participated in this study. Subjects were randomly allocated to a 10-week RT program (2 d·wk in the first 5 weeks; 3 d·wk in the last 5 weeks) or a nonexercise control group. Linear reverse periodization was used for the RT program. Cardiac autonomic modulation, mean blood pressure (MBP), peripheral vascular resistance (PVR), and resting heart rate (RHR) were measured before and after 10 weeks. The RT group reduced cardiac sympathetic modulation (0V%; B = -6.6; 95% confidence interval [CI]: -12.9 to -0.2; p = 0.045; Cohen's d = 0.88) and showed a trend for increased parasympathetic modulation (2V%; B = 12.5; 95% CI: 0-25; p = 0.050; Cohen's d = 0.87) compared with the control group. The RT group reduced MBP (B = -8.5 mm Hg; 95% CI: -13.6 to -3.4; p = 0.001; Cohen's d = 1.27), PVR (B = -14.1 units; 95% CI: -19.9 to -8.4; p < 0.001; Cohen's d = 1.86), and RHR (B = -8.8 b·min; 95% CI: -14.3 to -3.3; p = 0.002; Cohen's d = 1.20) compared with the control group. In the RT group, the changes in 2V% patterns and low-frequency components showed a correlation with changes in MBP (r = -0.60; p = 0.032) and RHR (r = 0.75; p = 0.0003). In conclusion, 10 weeks of RT improved cardiac autonomic modulation and reduced MBP and PVR in hypertensive older women. These results reinforce the importance of RT for this population.

Long-term stimulation of cardiac vagal preganglionic neurons reduces blood pressure in the spontaneously hypertensive rat

BACKGROUND

Arterial hypertension is associated with autonomic nervous system dysfunction. Different interventional strategies have been implemented in recent years for the reduction of sympathetic activity in patients with hypertension. However, the therapeutic benefit of increasing vagal tone in hypertensive patients remains largely unexplored.

OBJECTIVE

Here, we describe the effects of long-term activation of vagal neural pathways on arterial pressure, heart rate arterial pressure variability and spontaneous baroreflex sensitivity in spontaneously hypertensive rats (SHR) and normotensive Wistar rats.

METHODS

Brainstem vagal preganglionic neurons residing in the dorsal vagal motor nucleus (DVMN) were targeted with a lentiviral vector to induce the expression of an artificial G(s) protein-coupled receptor termed designer receptors exclusively activated by designer drugs (DREADD-Gs). The transduced neurons were activated daily by systemic administration of otherwise inert ligand clozapine-n-oxide. Arterial pressure measurements were recorded in conscious freely moving animals after 21 consecutive days of DVMN stimulation.

RESULTS

Resting arterial pressure was significantly lower in SHRs expressing DREADD-Gs in the DVMN, compared with control SHRs expressing enhanced green fluorescent protein. No changes in arterial pressure were detected in Wistar rats expressing DREADD-Gs compared with rats expressing enhanced green fluorescent protein in the DVMN. Pharmacogenetic activation of DREADD-Gs-expressing DVMN neurons in SHRs was accompanied with increased baroreflex sensitivity and a paradoxical decrease in cardio-vagal components of heart rate and systolic arterial pressure variability in SHRs.

CONCLUSION

These results suggest that long-term activation of vagal parasympathetic pathways is beneficial in restoring autonomic balance in an animal model of neurogenic hypertension and might be an effective therapeutic approach for the management of hypertension.

Neuroimmunology of the female brain across the lifespan: Plasticity to psychopathology

The female brain is highly dynamic and can fundamentally remodel throughout the normal ovarian cycle as well as in critical life stages including perinatal development, pregnancy and old-age. As such, females are particularly vulnerable to infections, psychological disorders, certain cancers, and cognitive impairments. We will present the latest evidence on the female brain; how it develops through the neonatal period; how it changes through the ovarian cycle in normal individuals; how it adapts to pregnancy and postpartum; how it responds to illness and disease, particularly cancer; and, finally, how it is shaped by old age. Throughout, we will highlight female vulnerability to and resilience against disease and dysfunction in the face of environmental challenges.

Exercise training initiated at old stage of lifespan attenuates aging-and ovariectomy-induced cardiac and renal oxidative stress: Role of baroreflex

BACKGROUND

The association of aging and menopause is a potent risk factor for cardiometabolic disease. We studied the impact of aerobic exercise training (ET) initiated in the old stage of lifespan in hemodynamics, metabolic, autonomic and oxidative stress.

METHODS

Aged (18 months old) female Wistar rats were divided into: ovariectomized and untrained (AG-OVX), and ovariectomized and trained (AG-OVXt, ET for 8 weeks). Intact aged (AG) and young female rats (3 months old; Y) were also studied. Blood pressure and metabolic parameters were measured. Baroreflex sensitivity (BRS) was studied by bradycardic (BR) and tachycardic (TR) responses to vasoactive drugs. Cardiac and renal lipid peroxidation (LPO), catalase (CAT), superoxide dismutase (SOD) and gluthatione peroxidase (GPx), and gluthatione redox balance (GSH/GSSG) were analyzed.

RESULTS

AG-OVXt group increased aerobic performance in 35%, decreased adipose tissue and triglycerides in 36% and 27%, respectively, and improved insulin tolerance in 50% in comparison to AG-OVX. AG-OVX presented hypertensive levels of blood pressure (systolic: 155 ± 5, diastolic: 111 ± 3 mmHg). In contrast, AG-OVXt presented blood pressure values similar to Y rats (systolic: 129 ± 3, diastolic: 112 ± 3 mmHg). TR and BR were reduced by 70% and 46%, respectively, in AG-OVX vs. Y. Once more, AG-OVXt presented similar results to Y. ET decreased LPO in the heart and kidney. In the latter, renal CAT and SOD were corrected by ET, while cardiac redox balance was partially recovered. Improved BRS was correlated with improved oxidative stress markers.

CONCLUSIONS

Even when initiated after aging and ovariectomy deleterious effects, ET is able to normalize BRS and highly improve cardiac and renal oxidative stress.

Resistance training and modulation of cardiac autonomic control in animal models: a systematic review

The purpose of the present review is to systematically evaluate the existing literature on the effects of resistance training (RT) on cardiac autonomic control in animal models. Electronic search was conducted in Pubmed, PEDro and Scopus databases from inception till June 2018. Randomised controlled trials and quasi-experimental trials which investigated the effects of RT (for at least 4 weeks) on cardiac autonomic control (assessed either by heart rate variability, baroreflex sensitivity or post-exercise heart rate recovery) in animal models were included. Out of the total 3,442 studies retrieved by the electronic search, 9 were found to be suitable as per the eligibility criteria and were included in this review. The majority of these studies (6 out of 9) demonstrated improvement in cardiovascular autonomic control after RT in animals; however, three studies did not illustrate any significant change. Standardised mean differences (SMD) showed a significant effect of RT on root mean square of successive differences between adjacent inter-beat (R-R) intervals (RMSSD) [SMD (confidence interval (CI)) = 4.56 (2.89, 6.23); P<0.0001] and bradycardic response to change in arterial blood pressure [SMD (CI)=-2.27 (-4.50, -0.03; P=0.05)] whereas no significant change was observed for other variables of cardiac autonomic control post-RT. The present systematic review do not give a clear conclusion regarding the effect of RT on cardiac autonomic control in animal models and thus highlight the need for good quality research in future.

Non-periodized and Daily Undulating Periodized Resistance Training on Blood Pressure of Older Women

The present study aimed at investigating the effects of a daily undulating periodization (DUP) and non-periodized (NP) resistance training programs on hemodynamic parameters of older women. Forty-two older women were randomized into one of the three experimental groups: NP, DUP, and control group (CG). Evaluations of the hemodynamic parameters occurred before, during and after the intervention. The exercise programs were performed twice a week over 22 weeks. NP and DUP groups were based on 3 sets of 8-10 repetitions in 9 exercises. In NP, the two exercise sessions were based on traditional strength training, which was performed at a Difficult intensity according to the rating of perceived exertion (RPE) method. In DUP, the first session was based on power resistance exercise, in which the concentric muscle contraction was performed as fast as possible at a moderate intensity based on RPE, while the second session was the same that was performed by NP. The findings demonstrated that diastolic blood pressure (90.4 vs. 76.2 mmHg) and mean arterial pressure (108.6 vs. 92.7 mmHg) were significantly reduced after NP, while no significant alterations were observed in DUP. Nevertheless, both training groups seem to have a cardio protective effect, since both training modes prevented the increase in HR reported in the experimental period in CG. In conclusion, our findings indicate that a 22-week NP resistance training program causes beneficial effects on hemodynamic parameters of older women. Trial Registration: NCT03443375.

Combined Aerobic and Resistance Exercise Training Improve Hypertension Associated With Menopause

The prevalence of hypertension sharply increases in menopausal women. Recent studies have demonstrated that aerobic or resistance training may help control hypertension. In this study, we report that combining aerobic and resistance training may provide an effective therapeutic approach for hypertension control, attenuating inflammation and oxidative stress in ovariectomized rats. Female Wistar and spontaneous hypertensive rats (SHR) were distributed into four groups: sedentary control (C), sedentary hypertensive (HR), sedentary hypertensive ovariectomized (HR-O), and combined trained hypertensive ovariectomized (T-HR-O). Combined exercise training was performed on a motor treadmill (aerobic training) and on a ladder adapted to rats (resistance training), in alternate days for 8 weeks. Direct arterial pressure was recorded and oxidative stress and inflammation were evaluated in cardiac and renal tissue. Ovariectomy increases increased mean arterial blood pressure, sympathetic modulation, and oxidative stress in SHR. Combining aerobic and resistance training reduced mean arterial blood pressure (12% vs. HR-O), heart rate (8% vs. HR-O), vascular sympathetic modulation (40% vs. HR-O), and improved baroreflex sensitivity. Combined training reduced cardiac inflammation (TNF and IL-6) and cardiac and renal lipoperoxidation (59% and 57%, respectively vs. HR-O). It also enhanced cardiac (71%) and renal (76%) total antioxidant capacity when compared to HR-O group. In conclusion, combining aerobic and resistance training improves mean arterial blood pressure, cardiovascular autonomic control, preventing cardiac and renal oxidative stress and inflammation in an experimental hypertension model with surgical menopause induced with ovariectomy.

Cardiovascular Benefits of Exercise Training in Postmenopausal Hypertension

Exercise training is often considered the cornerstone of nonpharmacological therapy for postmenopausal hypertension while aerobic exercise is the mainstay of life style modification for antihypertension. Moderate-intensity aerobic exercise is well tolerated on most days of the week by most people with postmenopausal hypertension and is not suspected to detract from exercise adherence. That being said, moderate aerobic exercise may be superior for eliciting cardiovascular benefits in hypertensive postmenopausal women and resistance exercise may offer desirable benefits. The beneficial outcomes of exercise training for hypertensive postmenopausal women include improvements in blood pressure, autonomic tone, baroreflex sensitivity, oxidative stress, nitric oxide (NO), bioavailability, and lipid profiles, as well as cardiovascular function and cardiorespiratory fitness. This partly explains the fact that exercise training programs have a positive effect for cardiovascular disease in hypertensive postmenopausal women. This review is to collect and present the literature of exercise training in postmenopausal hypertension. Our review may provide the current understanding of beneficial effects and mechanisms of exercise intervention for prevention and treatment of stage 1 to 2 hypertensive postmenopausal women.

Does resistance training modulate cardiac autonomic control? A systematic review and meta-analysis

PURPOSE

To systematically evaluate the literature on the effects of resistance training (RT) on cardiac autonomic control in healthy and diseased individuals.

METHODS

Electronic databases Pubmed, PEDro, and Scopus were systematically searched from their inception up to June 2018. Randomized controlled trials, quasi-experimental trials, and cross-over controlled trials investigating the effect of RT (of at least 4 weeks duration) on cardiac autonomic control assessed either by linear or non-linear measures of heart rate variability (HRV), baroreflex sensitivity, or post-exercise heart rate recovery were included. Of the studies retrieved, 28 were included in the systematic review. Meta-analysis was performed on 21 studies of the total 28 studies.

RESULTS

Quality and characteristic assessment revealed fair quality evidence. The majority of literature on healthy humans suggested no change in cardiac autonomic control following RT. Standardized mean differences (SMD) showed a significant effect of RT on root mean square of successive differences between adjacent inter-beat (R-R) intervals (RMSSD) [SMD 0.96, 95% confidence interval (CI) 0.20-1.73; p = 0.01], ratio of low- to high-frequency power of HRV (LF/HF ratio; SMD -0.72, 95% CI -1.03 to -0.42; p < 0.00001), standard deviation of the instantaneous beat-to-beat variability (SD1; SMD 1.78, 95% CI 1.07-2.49, p < 0.00001), and sample entropy (SMD 1.17, 95% CI 0.36-1.97, p = 0.005) in diseased individuals.

CONCLUSION

This rigorous systematic analysis revealed that RT has no or minimal effects on cardiac autonomic control of healthy individuals, but RT leads to improvement in cardiac autonomic control of diseased individuals.

Association between Diastolic Dysfunction with Inflammation and Oxidative Stress in Females ob/ob Mice

Objective: To evaluate autonomic and cardiovascular function, as well as inflammatory and oxidative stress markers in ob/ob female mice.

Methods: Metabolic parameters, cardiac function, arterial pressure (AP), autonomic, hormonal, inflammatory, and oxidative stress markers were evaluated in 12-weeks female wild-type (WT group) and ob/ob mice (OB group).

Results: OB animals showed increased body weight, blood glucose, and triglyceride levels, along with glucose intolerance, when compared to WT animals. Ejection fraction (EF) and AP were similar between groups; however, the OB group presented diastolic dysfunction, as well as an impairment on myocardial performance index. Moreover, the OB group exhibited important autonomic dysfunction and baroreflex sensitivity impairment, when compared to WT group. OB group showed increased Angiotensin II levels in heart and renal tissues; decreased adiponectin and increased inflammatory markers in adipose tissue and spleen. Additionally, OB mice presented a higher damage to proteins and lipoperoxidation and lower activity of antioxidant enzymes in kidney and heart. Correlations were found between autonomic dysfunction with angiotensin II and inflammatory mediators, as well as between inflammation and oxidative stress.

Conclusions: Our results showed that female adult ob/ob mice presented discrete diastolic dysfunction accompanied by autonomic disorder, which is associated with inflammation and oxidative stress in these animals.