Positive effect of combined exercise training in a model of metabolic syndrome and menopause: autonomic, inflammatory, and oxidative stress evaluations

Low-intensity exercise prevents cardiac inflammation through the NF-κB/TNFα pathway in insulin-resistant male rats

Our previously published results have proven that low-intensity exercise, equivalent to brisk walking, is beneficial in managing cardiac insulin resistance in post-weaning male rats exposed to a fructose-rich diet. Still, its role in protecting against cardiac inflammation is unclear. This experiment was designed to investigate the preventive effect of low-intensity exercise on cardiac inflammation in male post-weaning rats exposed to a fructose-rich diet (10%). Male Wistar rats were randomly assigned to a sedentary control group, a sedentary group with fructose overload, and a fructose overload group subjected to treadmill exercise for nine weeks. Protein expression of cardiac inducible nitric oxide synthase (iNOS), matrix metalloproteinase 9, as well as cellular localization/phosphorylation of nuclear factor kappa B (NF-κB), and α1 and α2 subunits of sodium-potassium ATPase pump (Na/K-ATPase) was determined. Additionally, gene expression of tumor necrosis factor α (TNFα) and suppressor of cytokine signaling 3 (SOCS3) was examined. The results demonstrate that a chronic fructose-rich diet in sedentary rats elevates the expression of key inflammatory markers, including SOCS3, TNFα, NF-κB, and iNOS, as well as the plasma membrane α1 and α2 subunits. Exercise prevented alterations induced by a fructose-rich diet, except iNOS expression. Additionally, exercise increased the protein expression of the α1 and α2 subunits of Na/K-ATPase in the lysate of fructose-fed rats. These findings suggest that low-intensity exercise is an effective non-invasive strategy for cardioprotection, helping to prevent inflammation by modulating TNFα and NF-κB expression in insulin-resistant hearts of post-weaning male rats.

The phytoestrogen genistein improves hippocampal neurogenesis and cognitive impairment and decreases neuroinflammation in an animal model of metabolic syndrome

Metabolic syndrome (MS) is the medical term for the combination of at least three of the following factors: obesity, hyperlipidemia, hyperglycemia, insulin resistance, and hypertension. The spontaneously hypertensive rat (SHR) is an accepted animal model for the study of human MS that reveals all the features of the syndrome when fed high-fat, high-carbohydrate diets. The intake of high-fat diets in rats has been shown to produce brain neuropathology. In humans, MS increases the risk of cognitive impairment, dementia, and Alzheimer's disease. Genistein (GEN) is a phytoestrogen found in soy that lacks feminizing and carcinogenic effects and was found to have neuroprotective and anti-inflammatory effects in many pathological conditions. Considering that multiple data support that natural phytoestrogens may be therapeutic options for CNS maladies, we aim to elucidate if these properties also apply to a rat model of MS. Thus, GEN effects on neuroinflammation, neurogenesis, and cognition were evaluated in SHR eating a fat/carbohydrate-enriched diet. To characterize the neuropathology and cognitive dysfunction of MS we fed SHR with a high-fat diet (4520 kcal/kg) along with a 20% sucrose solution to drink. MS rats displayed a significant increase in body weight, BMI and obesity indexes along with an increased in fasting glucose levels, glucose intolerance, high blood pressure, and high blood triglyceride levels. MS rats were injected with GEN during 2 weeks a dose of 10 mg/kg. We found that MS rats showed a decreased number of DCX+ neural progenitors in the dentate gyrus and treatment with GEN increased this parameter. Expression of GFAP was increased in the DG and CA1 areas of the hippocampus and treatment decreased astrogliosis in all of them. We measured the expression of IBA1+ microglia in the same regions and classified microglia according to their morphology: we found that MS rats presented an increased proportion of the hypertrophied phenotype and GEN produced a shift in microglial phenotypes toward a ramified type. Furthermore, colocalization of IBA1 with the proinflammatory marker TNFα showed increased proportion of proinflammatory microglia in MS and a reduction with GEN treatment. On the other hand, colocalization with the anti-inflammatory marker Arg1 showed that MS has decreased proportion of anti-inflammatory microglia and GEN treatment increased this parameter. Cognitive dysfunction was evaluated in rats with MS using a battery of behavioral tests that assessed hippocampus-dependent spatial and working memory, such as the novel object recognition test (NOR), the novel object location test (NOL), and the free-movement pattern Y-maze (FMP-YMAZE) and the d-YMAZE. In all of them, MS performed poorly and GEN was able to improve cognitive impairments. These results indicate that GEN was able to exert neuroprotective actions increasing neurogenesis and improving cognitive impairments while decreasing astrogliosis, microgliosis, and neuroinflammatory environment in MS rats. Together, these results open an interesting possibility for proposing this phytoestrogen as a neuroprotective therapy for MS.

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.

Comparison of Metabolic Risk Factors Based on the Type of Physical Activity in Korean Adolescents: Results from a Nationwide Population-Based Survey

BACKGROUND

Physical activity (PA) is associated with a favorable metabolic risk profile in adults. However, its role in adolescents remains unclear. In this study, using data (2019-2021) from the 8th Korea National Health and Nutrition Examination Survey, we investigated the optimal exercise type for preventing metabolic complications in adolescents.

METHODS

A total of 1,222 eligible adolescent participants (12-18-year-old) were divided into four groups as follows: aerobic exercise (AE), resistance exercise (RE), combined aerobic and resistance exercise (CE), and no exercise (NE). Daily PA was assessed using the international PA questionnaire. Blood samples were collected to measure lipid, glucose, and insulin levels. Additionally, the homeostasis model assessment for insulin resistance (HOMA-IR) and triglyceride-glucose (TyG) indices were measured. Multivariate regression analysis was used to compare the metabolic risk factors across the PA groups before and after propensity score matching (PSM) adjustment for confounding variables.

RESULTS

The CE group exhibited improved fasting glucose levels, lower TyG index, reduced white blood cell count, and higher high-density lipoprotein (HDL) cholesterol levels than the NE group. The RE group exhibited lower mean blood pressure, triglyceride, fasting insulin, HOMA-IR, TyG index and a reduced risk of metabolic syndrome than the NE group. The AE group had higher total and HDL cholesterol levels. In detailed comparison of the AE and RE groups, the RE group consistently exhibited favorable metabolic parameters, including lower blood pressure and total and low-density cholesterol levels, which persisted after PSM.

CONCLUSION

These findings highlight the positive effects of PA on cardiovascular risk factors in adolescents. Thus, RE may have a more favorable metabolic effect than AE. Further studies are needed to validate the benefits of exercise according to the exercise type.

Insulin Treatment Does Not Prevent EARLY Autonomic Cardiovascular and Diastolic Dysfunctions in Streptozotocin-Induced Diabetic Rats

Recent studies have found increased cardiovascular mortality risk in patients with type 1 diabetes when compared to normoglycemic people, even when they were kept under good glycemic control. However, the mechanisms underlying this condition have yet to be fully understood. Using streptozotocin (STZ)-induced diabetic rats, we evaluated the effects of insulin replacement therapy on cardiac, autonomic, inflammatory, and oxidative stress parameters. Daily treatment with insulin administrated subcutaneously in the STZ-diabetic rats showed a reduction in hyperglycemia (>250 mg/dL) to normalized values. The insulin treatment was effective in preventing alterations in cardiac morphometry and systolic function but had no impact on diastolic function. Also, the treatment was not able to prevent the impairment of baroreflex-tachycardic response and systolic arterial pressure variability (SAP-V). A correlation was found between improvement of these autonomic parameters and higher levels of IL-10 and lower levels of oxidized glutathione. Our findings show that insulin treatment was not able to prevent diastolic, baroreflex, and SAP-V dysfunction, suggesting an outstanding cardiovascular risk, even after obtaining a good glycemic control in STZ-induced diabetic rats. This study shed light on a relatively large population of diabetic patients in need of other therapies to be used in combination with insulin treatment and thus more effectively manage cardiovascular risk.

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.

Endocrine Changes in Postmenopausal Women: A Comprehensive View

Menopause, when menstrual cycles stop, is brought on by a decline in the level of the hormones progesterone and oestrogen synthesised by the ovaries. Menopause is an unavoidable stage of a female's lifecycle, but because experiences differ for every woman, several women require health care aid to manage their health problems. The physiological variations that take place at various periods of the reproducing age, along with the kind and timing of menopause, are components that are frequently associated with a greater threat of cardiometabolic illness. The most researched associations between menopause and cardiometabolic health are reduced levels of ovarian estrogen synthesis and excessive amounts of androgen during the onset of menopause. Although testosterone and oestrogens have differing effects on adipocyte physiology, it is debatable how important oestrogens are for the emergence of metabolic disorders following menopause. The control of adipocyte differentiation by the brain as well as potential roles of oestrogen and endocrine disruptors chemicals are reviewed in this systematic review of the subject. In general, women had a greater frequency of metabolic syndrome compared to men. Female metabolism was significantly impacted by overt hyperthyroidism and subclinical hypothyroidism. Osteoporosis is another medical condition that menopausal women may experience. Estrogen deprivation is the main contributor to osteoporosis in menopausal women. The regular cycle of bone turnover is disrupted by the decrease in estrogen secretion, which boosts osteoclastic resorption activity while decreasing osteoblastic activity. The entire article assesses and provides information on all the changes in a woman's life after menopause.

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.

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.

EFFECTS OF A 4-WEEK MICRO-HYPERBARIC OXYGEN INTERVENTION ON OXIDATION-ANTIOXIDATION SYSTEM FUNCTION

ABSTRACT Introduction Hyperbaric oxygen intervention has an important effect on the function of the body’s oxidation-antioxidant system. Objective To verify the effects of a 4-week micro-hyperbaric oxygen intervention on oxidation-antioxidation system function in skeleton athletes. Methods The experimental group underwent a 1.3 ATA HBO intervention for 4 weeks and the control group underwent natural recovery. The levels of MDA, PC, SOD, CAT, GSH-PX, T-AOC, BU, CK, T, and C of the two groups were measured at Week 0, Week 2, and Week 4. Results The MDA, PC, and CK of the Exp group were significantly lower than Con group (P < 0.05) in Week 4. The SOD, CAT, and T-AOC of the Exp group were significantly higher in Week 4 than in Week 0 (P < 0.05) and significantly higher than the Con group values (P < 0.05). Conclusions A four-week 1.3 ATA HBO intervention decreased the level of oxidative stress, increased the activity of antioxidant enzymes, and reduced the degree of exercise fatigue in skeleton athletes. Level of Evidence II; Therapeutic studies - Investigating treatment results.

Free-radical oxidation as a pathogenetic factor of metabolic syndrome

The medical and social significance of cardiovascular diseases remains high. One of the factors that determine cardiovascular risks is metabolic syndrome. As a result of excessive accumulation of lipid and carbohydrate metabolism products in metabolic syndrome, oxidative (oxidative) stress develops. The article considers both domestic and foreign scientific studies, which highlight various aspects of the influence of reactive oxygen and nitrogen species, as well as other free radicals on the formation of oxidative stress in pathological conditions that are part of the metabolic syndrome complex. This describes the mechanisms of the formation of chronic inflammation through excessive secretion of pro-inflammatory cytokines and adipokines, activation of the transcription factor NF-kB, as well as damage to the antioxidant system in obesity. Separately, a number of mechanisms of the stimulating effect of adipokines: leptin, adiponectin, chimerine, omentin 1, resistin, on the formation of oxidative stress have been noted. The ways of activating the polyol pathway, as well as diacyl-glycerol — protein kinase C — the signaling pathway of oxidative stress, the formation of mitochondrial dysfunction is described. As a result of which there is an excessive production of free radicals in insulin resistance, diabetes mellitus and macroand microvascular complications of diabetes. In addition, the influence of oxidative stress directly on the formation of cardiovascular diseases of atherosclerotic genesis, as well as arterial hypertension, has been shown.

Benefits of combined exercise training on arterial stiffness and blood pressure in spontaneously hypertensive rats treated or not with dexamethasone

Dexamethasone (DEX)-induced arterial stiffness is an important side-effect, associated with hypertension and future cardiovascular events, which can be counteracted by exercise training. The aim of this study was to evaluate the mechanisms induced by combined training to attenuate arterial stiffness and hypertension in spontaneously hypertensive rats treated or not with dexamethasone. Spontaneously hypertensive rats (SHR) underwent combined training for 74 days and were treated with dexamethasone (50 µg/kg s. c.) or saline solution during the last 14 days. Wistar rats were used as controls. Echocardiographic parameters, blood pressure (BP) and pulse wave velocity (PWV), as well as histological analyses of the heart and aorta, carotid and femoral arteries were performed. At the beginning, SHR had higher BP and PWV compared with Wistar rats. After 60 days, while BP increased in sedentary SHR, combined exercise training decreased BP and PWV. After 74d, the higher BP and PWV of sedentary SHR was accompanied by autonomic imbalance to the heart, cardiac remodeling, and higher arterial collagen deposition. DEX treatment did not change these parameters. On the other hand, trained SHR had reduced BP and PWV, which was associated with better autonomic balance to the heart, reduced myocardial collagen deposition, as well as lower arterial collagen deposition. The results of this study suggest that combined training, through the reduction of aortic collagen deposition, is an important strategy to reduce arterial stiffness in spontaneously hypertensive rats, and these lower responses were maintained regardless of dexamethasone treatment.

Effects of Concurrent Aerobic Plus Resistance Training on Blood Pressure Variability and Blood Pressure Values in Patients with Hypertension and Coronary Artery Disease: Gender-Related Differences

The purpose of this study was to compare changes in blood pressure variability (BPV) and blood pressure (BP) values occurring in response to concurrent training (CT) between the two genders. A total of 35 males and 20 women aged 55–80 years, with hypertension and coronary artery disease, were included. They underwent a 12-week CT program. The aerobic component of CT was performed according to the rate of perceived exertion while the intensity of the resistance component was set at 60% of 1 repetition maximum for the first 4 weeks and then increased to 80%. BP and BPV were evaluated at baseline and at the end of the CT program through 24 h ambulatory blood pressure monitoring. After 12-weeks, 24 h and daytime systolic BPV decreased in both men and women without significant between-groups differences. Twenty-four-hour daytime and nighttime diastolic BPV decreased in both genders with a significantly greater decrease in women compared to men. Twenty-four-hour daytime systolic and 24 h diastolic BP decreased in men while they were unchanged in women. In conclusion, CT induced similar reductions of systolic BPV in men and women and a greater decrease in diastolic BPV in women. Conversely, CT decreased BP values in males but not in females. CT appears to be an effective intervention for reducing BPV in both genders.

Effects of Exercise Training on the Autonomic Nervous System with a Focus on Anti-Inflammatory and Antioxidants Effects

Studies show that the autonomic nervous system (ANS) has an important impact on health in general. In response to environmental demands, homeostatic processes are often compromised, therefore determining an increase in the sympathetic nervous system (SNS)’s functions and a decrease in the parasympathetic nervous system (PNS)’s functions. In modern societies, chronic stress associated with an unhealthy lifestyle contributes to ANS dysfunction. In this review, we provide a brief introduction to the ANS network, its connections to the HPA axis and its stress responses and give an overview of the critical implications of ANS in health and disease—focused specifically on the immune system, cardiovascular, oxidative stress and metabolic dysregulation. The hypothalamic–pituitary–adrenal axis (HPA), the SNS and more recently the PNS have been identified as regulating the immune system. The HPA axis and PNS have anti-inflammatory effects and the SNS has been shown to have both pro- and anti-inflammatory effects. The positive impact of physical exercise (PE) is well known and has been studied by many researchers, but its negative impact has been less studied. Depending on the type, duration and individual characteristics of the person doing the exercise (age, gender, disease status, etc.), PE can be considered a physiological stressor. The negative impact of PE seems to be connected with the oxidative stress induced by effort.

The Effects of Aerobic-Resistance Training and Broccoli Supplementation on Plasma Dectin-1 and Insulin Resistance in Males with Type 2 Diabetes

Background: This study aimed to evaluate the effects of a combination of aerobic-resistance training (CARET) and broccoli supplementation on dectin-1 levels and insulin resistance in men with type 2 diabetes mellitus (T2D). Methods: Forty-four males with T2D were randomly allocated to four groups (n = 11 each group): CARET + broccoli supplement (TS), CARET + placebo (TP), control + broccoli supplement (S), and control + placebo (CP). CARET was performed three days per week for 12 weeks. TS and S groups received 10 g of broccoli supplement per day for 12 weeks. All variables were assessed at baseline and 12 weeks. Results: Plasma dectin-1 levels were decreased in TS and TP groups compared with the CP group (p < 0.05). Cardiometabolic risk factors showed significant reductions in TP and TS groups compared to S and CP groups (p < 0.05). Conclusion: The combination of CARET and broccoli supplementation produced the largest improvements in insulin resistance and dectin-1 and other complications of T2D.

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.

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.

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.

Coexistence of metabolic syndrome and osteopenia associated with social inequalities and unhealthy lifestyle among postmenopausal women in South Korea: the 2008 to 2011 Korea National Health and Nutritional Examination Survey (KNHANES)

OBJECTIVE

The prevalence of metabolic syndrome (MetS) and osteoporosis (OP) among postmenopausal women has been rapidly increasing. We examined the associations between socioeconomic status-related factors, unhealthy lifestyle, and the coexistence of MetS and osteopenia or OP.

METHODS

One thousand nine hundred ninety-one postmenopausal women aged 45 to 65 years were used to select a representative sample of the civilian, noninstitutionalized South Korean population from the 2008 to 2011 Korea National Health and Nutrition Examination Survey data. Women were grouped as neither MetS nor OP (normal), MetS, OP, and both MetS and OP (MetS + OP). Socioeconomic status (education, household income, place of residence, employment status), health-related behaviors (physical activity, alcohol consumption, smoking), and diet-related factors (intake of nutrients and food groups, eating habits, food insecurity) were obtained. Logistic regression models were used to examine the odds ratio (OR) and 95% confidence interval (CI).

RESULTS

The prevalence of MetS + OP was 32.5%. The average number of MetS risk factors in MetS + OP was 3.5, higher than that of normal and OP groups (P < 0.001). Bone mineral density at all sites was significantly lower in MetS + OP than normal and MetS groups (P < 0.001). Also, calcium, phosphorus, vitamin A, riboflavin, and niacin levels were lowest in the MetS + OP group compared with the three other groups (P < 0.05). After controlling for covariates, low-income and low-education women were more likely to have MetS + OP (OR 1.97, 95% CI 1.04-3.72); high-income and high-education group was 70% less likely to have MetS + OP (OR 0.30, 95% CI 0.10-0.86) compared with the middle-income and middle-education group.

CONCLUSIONS

Social inequalities might be powerful contributors in Korean postmenopausal women with coexistence of MetS and OP. Therefore, social and political perspective approaches are required in this population for prevention and treatment of MetS and OP. Future studies should explore to find controllable factors and thereby improve health status in postmenopausal women.

Aerobic Training Is Better Than Resistance Training on Cardiac Function and Autonomic Modulation in Female ob/ob Mice

Objective: This study evaluated the effects of aerobic, resistance, and combined exercise training on cardiac function and autonomic modulation in female ob/ob mice. Methods: Four-week-old female wild type and obese (ob/ob) mice were divided into five groups (n = 8): control (WT), obese (OB) obese + aerobic training (OBA), obese + resistance training (OBR), and obese + combined training (OBC). The exercise training was performed on treadmill and/or ladder at 40-60% maximum test during 8 weeks. Cardiac function was measured using echo machine. Heart rate variability (HRV) was evaluated in the time and frequency domain. Results: OB group presented higher body weight gain (~600%), glycemia (~44%) and glucose intolerance (~150%), reduction of cardiac vagal modulation, evidenced by a lower RMMSD (~56%), total power and high frequency band, and a higher isovolumic relaxation time (IVRT) (~24%) in relation to the WT group. Aerobic and combined training led to a lower IVRT (OBA: ~14%; OBC: ~14%) and myocardial global index (OBA: ~37%; OBC: ~44%). The OBA group presented an increased in vagal indexes of HRV than the other ob/ob groups. A negative correlation was observed between the delta of aerobic exercise capacity and MPI (r = 0.45; p = 0.002) and exercise capacity and body weight gain (r = 0.39; p = 0.002). Conclusion: Only the obese females underwent to aerobic exercise training showed improvement in cardiac function and HRV. Moreover, the aerobic exercise capacity as well as a greater responsivity to aerobic exercise training is intimately associated with these improvements, reinforcing the importance of aerobic exercise training to this population.

Exercise benefits the cardiac, autonomic and inflammatory responses to organophosphate toxicity

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DFP promotes cardiac and autonomic dysfunction.

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DFP led to mild neuroinflammation.

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Exercise training prevents/attenuates some of the impairments provoked by DFP.

The organophosphate, diisopropyl fluorophosphate (DFP), may impair cardiovascular, autonomic and immune function while exercise training is thougt to be restorative. Experiments determined effects of wheel exercise in C57B1 male mice, testing cardiovascular and autonomic function and characterization of the immunological profile. Sedentary (S) and exercise (ET) groups were treated with corticosterone (CORT) followed by injection of DFP. This model was associated with systolic and diastolic dysfunction in the S group, measured using echocardiography (ECHO). Chronic exercise ameliorated the cardiac deficit. Autonomic balance, accessed by heart rate variability (HRV), showed increased sympathetic and decreased parasympathetic modulation in S group. Autonomic balance in ET mice was not affected by DFP. Our DFP model resulted in mild neuroinflammation seen by increased IL5, IL12 and MIP2 in brain and plasma IL6 and IL1a. DFP had a negative impact on cardiac/autonomic function and inflammatory markers, effects reduced by exercise. Data suggest a beneficial effect of exercise training on the cardiovascular and autonomic responses to DFP/CORT.

Combined Exercise Training Performed by Elderly Women Reduces Redox Indexes and Proinflammatory Cytokines Related to Atherogenesis

Cardiovascular benefits for the general population of combined aerobic-resistance exercise training are well-known, but the impact of this exercise training modality on the plasma lipid, inflammatory, and antioxidant status in elderly women that are exposed to a great risk of developing ischemic cardio- and cerebrovascular diseases has not been well investigated. So, we aimed to evaluate the plasma lipids, oxidative stress, and inflammatory cytokines in 27 elderly women (TRAINED group, 69.1 ± 8.1 yrs) that were performing moderate intensity combined aerobic-resistance exercise training (3 times/week for at least 18 months) and in 27 sedentary elderly women (SED group, 72.0 ± 6.4 yrs), not submitted to exercise training for at least 5 yrs. Our results showed that BMI was lower in the TRAINED group than in the SED group (25.1 ± 3.2 vs. 28.7 ± 5.1, p < 0.05). The TRAINED group had lower glycemia (92 ± 3 vs. 118 ± 12, p < 0.05), glycated hemoglobin (5.9 ± 0.1 vs. 6.4 ± 0.2, p < 0.05), and triglycerides (98 (75-122) vs. 139 (109-214), p < 0.01); equal total cholesterol (199 (175-230) vs. 194 (165-220)), LDL-cholesterol (108 (83-133) vs. 109 (98-136)), and non-HDL-cholesterol (54 (30-74) vs. 62 (26-80)); and also higher HDL-cholesterol (64 (52-77) vs. 52 (44-63), p < 0.01) and LDL-C/oxLDL ratio (13378 ± 2570 vs. 11639 ± 3113, p < 0.05) compared to the SED group. Proinflammatory cytokines as IL-1β (11.31 ± 2.4 vs. 28.01 ± 4.7, p < 0.05), IL-6 (26.25 ± 7.4 vs. 49.41 ± 17.8, p < 0.05), and TNF-α (25.72 ± 2.8 vs. 51.73 ± 4.2, p < 0.05) were lower in the TRAINED group than in the SED group. The TRAINED group had lower total peroxides (26.3 ± 7.4 vs. 49.0 ± 17.8, p < 0.05) and oxidized LDL (1551 ± 50.33 vs. 1773 ± 74, p < 0.02) and higher total antioxidant capacity (26.25 ± 7.4 vs. 49.41 ± 17.8, p < 0.001) compared to the SED group. In conclusion, in TRAINED women, BMI was lower, plasma lipid profile was better, plasma oxidative stress was diminished, and there was less expression of proinflammatory interleukins than in SED, suggesting that combined aerobic-resistance exercise training may promote the protection against the complications of ischemic cardio- and cerebrovascular disease in elderly women.

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.

Preventive effect of exercise training on diabetic kidney disease in ovariectomized rats with type 1 diabetes

IMPACT STATEMENT

To date, no studies have been found evaluating the effects of physical exercise on renal function and structure changes in ovariectomized rats with type 1 diabetes. Therefore, this work emerges with an important tool for strengthening and expanding innovative research on exercise with potential for the prevention of renal diseases in ovariectomized diabetic rats, and future development of studies that seek to increase scientific knowledge about the beneficial effects of physical exercise on renal diseases in humans.

The mechanical and biochemical properties of tail tendon in a rat model of obesity: Effect of moderate exercise and prebiotic fibre supplementation

The worldwide trajectory of increasing obesity rates is a major health problem precipitating a rise in the prevalence of a variety of co-morbidities and chronic diseases. Tendinopathy, in weight and non-weight bearing tendons, in individuals with overweight or obesity has been linked to metabolic dysfunction resulting from obesity. Exercise and dietary fibre supplementation (DFS) are common countermeasures to combat obesity and therefore it seems reasonable to assume that they might protect tendons from structural and mechanical damage in a diet-induced obesity (DIO) model. The purpose of this study was to determine the effects of a DIO, DIO combined with moderate exercise, DIO combined with DFS (prebiotic oligofructose), and DIO combined with moderate exercise and DFS on the mechanical and biochemical properties of the rat tail tendon. Twenty-four male Sprague-Dawley rats, fed a high-fat/high-sucrose diet were randomized into a sedentary, a moderate exercise, a DFS, or a moderate exercise combined with DFS group for 12 weeks. Additionally, six lean age-matched animals were included as a sedentary control group. DIO in combination with exercise alone and with exercise and DFS reduced the Young's Modulus but not the collagen content of the rat tail tendons compared to lean control animals. However, no differences in the mechanical and biochemical properties of the rat tail tendon were detected between the DIO and the lean control group, suggesting that DIO by itself did not impact the tail tendon. It seems that longer DIO exposure periods may be needed to develop overt differences in our DIO model.

Low-intensity exercise in the prevention of cardiac insulin resistance-related inflammation and disturbances in NOS and MMP-9 regulation in fructose-fed ovariectomized rats

Exercise is important nonpharmacological treatment for improvement of insulin sensitivity in menopause. However, its effect on menopausal cardiac insulin resistance is needing further research. We investigated protective effects of low-intensity exercise on cardiac insulin signaling, inflammation, regulation of nitric oxide synthase (NOS) and matrix metalloproteinase 9 (MMP-9) in ovariectomized (OVX) Wistar rats, submitted to 10% fructose solution for 9 weeks. OVX rats were divided into control, sedentary fructose, and exercise fructose groups. Measurements of physical and biochemical characteristics were carried out to evaluate metabolic syndrome development. Messenger RNA and protein levels and phosphorylation of cardiac insulin signaling molecules, endothelial and inducible NOS (eNOS and iNOS), p65 subunit of nuclear factor κB (NFκB), tumor necrosis factor α (TNF-α), suppressor of cytokine signaling 3 (SOCS3), and MMP-9 were analyzed. Fructose increased insulin level, homeostasis model assessment (HOMA) index, and visceral adipose tissue weight, while low-intensity exercise prevented insulin level and HOMA index increase. Fructose also decreased cardiac pAkt (Ser473), peNOS (Ser1177) and increased insulin receptor substrate 1 (IRS1) phosphorylation at Ser307, pNFκB (Ser276) and NFκB and MMP-9 content, without any effect on iNOS, protein-tyrosine phosphatase 1B, TNF-α, and SOCS3. Exercise prevented changes in pIRS1 (Ser307), pAkt (Ser473), peNOS (Ser1177), pNFκB (Ser276), and NFκB expression. In addition, exercise increased pIRS1 (Tyr632), pAkt (Thr308), and eNOS expression. Low-intensity exercise prevented cardiac insulin signaling disarrangement in fructose-fed OVX rats and therefore eNOS dysfunction, as well as pro-inflammatory signaling activation, without effect on tissue remodeling, suggesting physical training as a way to reduce cardiovascular risk.

Protective effect of prebiotic and exercise intervention on knee health in a rat model of diet-induced obesity

Obesity, and associated metabolic syndrome, have been identified as primary risk factors for the development of knee osteoarthritis (OA), representing nearly 60% of the OA patient population. In this study, we sought to determine the effects of prebiotic fibre supplementation, aerobic exercise, and the combination of the two interventions, on the development of metabolic knee osteoarthritis in a high-fat/high-sucrose (HFS) diet-induced rat model of obesity. Twelve-week-old male Sprague-Dawley rats were randomized into five groups: a non-exercising control group fed a standard chow diet, a non-exercising group fed a HFS diet, a non-exercising group fed a HFS diet combined with prebiotic fibre supplement, an exercise group fed a HFS diet, and an exercise group fed a HFS diet combined with prebiotic fibre supplement. Outcome measures included knee joint damage, percent body fat, insulin sensitivity, serum lipid profile, serum endotoxin, serum and synovial fluid cytokines and adipokines, and cecal microbiota. Prebiotic fibre supplementation, aerobic exercise, and the combination of the two interventions completely prevented knee joint damage that is otherwise observed in this rat model of obesity. Prevention of knee damage was associated with a normalization of insulin resistance, leptin levels, dyslipidemia, gut microbiota, and endotoxemia in the HFS-fed rats.

Cholinergic Stimulation by Pyridostigmine Bromide Before Myocardial Infarction Prevent Cardiac and Autonomic Dysfunction

Inflammatory processes and cardiovascular autonomic imbalance are very relevant characteristic of the enormous dynamic process that is a myocardial infarction (MI). In this sense, some studies are investigating pharmacological therapies using acetylcholinesterase inhibitors, such as pyridostigmine bromide (PYR), aiming to increase parasympathetic tone after MI. Here we hypothesized that the use of PYR before the MI might bring an additional positive effect to the autonomic function, and consequently, in the inflammatory response and cardiac function. The present study aimed to evaluate left ventricular function, baroreflex sensitivity, autonomic modulation, and inflammatory profile in PYR-treated rats previously to MI. Methods: Male Wistar rats (250–300 g) were treated for 60 days with PYR. After treatment, they were submitted to the MI. After the MI, the autonomic and ventricular function were evaluated, as well as the systemic, left ventricle, and adipose tissue inflammatory profile. Results: PYR, performed before MI, prevented HR increase, systolic function impairment, baroreflex sensitivity drop, as well as pulse interval variance, RMSSD, blood pressure and parasympathetic modulation reduction in treated rats compared to untreated rats. Also, this positive functional changes may have been a result of the reduced inflammatory parameters in the left ventricle (IFN-γ, IL-6, and IL-1β), as well as increased IL-10 expression and IL-10/TNF-α ratio in treated animals before MI. Conclusion: Prior treatment with PYR prevents impairment of the autonomic nervous system after MI, which may be associated with the attenuated expression of inflammatory factors and heart dysfunction.

Effects of high-intensity interval training on vascular function in breast cancer survivors undergoing anthracycline chemotherapy: design of a pilot study

INTRODUCTION

Cardiovascular disease (CVD) mortality is higher among breast cancer survivors (BCS) who receive chemotherapy compared with those not receiving chemotherapy. Anthracycline chemotherapy is of particular concern due to anthracycline-related impairment of vascular endothelial cells and dysregulation of the extracellular matrix. One strategy proven to offset these impairments is a form of exercise known as high-intensity interval training (HIIT). HIIT improves endothelial function in non-cancer populations by decreasing oxidative stress, the main contributor to anthracycline-induced vascular dysfunction. The purpose of this pilot study is to assess the feasibility of an 8-week HIIT, as well as the HIIT effects on endothelial function and extracellular matrix remodelling, in BCS undergoing anthracycline chemotherapy.

METHODS AND ANALYSIS

Thirty BCS are randomised to either HIIT, an 8-week HIIT intervention occurring three times per week (seven alternating bouts of 90% of peak power output followed by 10% peak power output), or delayed group (DEL). Feasibility of HIIT is assessed by (1) the percentage of completed exercise sessions and (2) the number of minutes of exercise completed over the course of the study. Vascular function is assessed using brachial artery flow-mediated dilation and carotid intima media thickness. Extracellular matrix remodelling is assessed by the level of matrix metalloproteinases in the plasma. A repeated-measures analysis of covariance model will be performed with group (HIIT and DEL group) and time (pre/post assessment) as independent factors. We hypothesise that HIIT will be feasible in BCS undergoing anthracycline chemotherapy, and that HIIT will improve endothelial function and extracellular matrix remodelling, compared with the DEL group. Success of this study will provide evidence of feasibility and efficacy to support a larger definitive trial which will impact cancer survivorship by decreasing anthracycline-induced vascular dysfunction, thereby benefiting cardiovascular markers that are related to CVD risk.

ETHICS AND DISSEMINATION

This trial was approved by the University of Southern California Institutional Review Board (HS-15-00227).

TRIAL REGISTRATION NUMBER

NCT02454777; Pre-results.

Cross-Talk Between Insulin Signaling and G Protein-Coupled Receptors

Diabetes is a major risk factor for the development of heart failure. One of the hallmarks of diabetes is insulin resistance associated with hyperinsulinemia. The literature shows that insulin and adrenergic signaling is intimately linked to each other; however, whether and how insulin may modulate cardiac adrenergic signaling and cardiac function remains unknown. Notably, recent studies have revealed that insulin receptor and β2 adrenergic receptor (β2AR) forms a membrane complex in animal hearts, bringing together the direct contact between 2 receptor signaling systems, and forming an integrated and dynamic network. Moreover, insulin can drive cardiac adrenergic desensitization via protein kinase A and G protein-receptor kinases phosphorylation of the β2AR, which compromises adrenergic regulation of cardiac contractile function. In this review, we will explore the current state of knowledge linking insulin and G protein-coupled receptor signaling, especially β-adrenergic receptor signaling in the heart, with emphasis on molecular insights regarding its role in diabetic cardiomyopathy.

Photobiomodulation Leads to Reduced Oxidative Stress in Rats Submitted to High-Intensity Resistive Exercise

The aim of this study was to determine whether oxidative stress markers are influenced by low-intensity laser therapy (LLLT) in rats subjected to a high-intensity resistive exercise session (RE). Female Wistar rats divided into three experimental groups (Ctr: control, 4J: LLLT, and RE) and subdivided based on the sampling times (instantly or 24 h postexercise) underwent irradiation with LLLT using three-point transcutaneous method on the hind legs, which was applied to the gastrocnemius muscle at the distal, medial, and proximal points. Laser (4J) or placebo (device off) were carried out 60 sec prior to RE that consisted of four climbs bearing the maximum load with a 2 min time interval between each climb. Lipoperoxidation levels and antioxidant capacity were obtained in muscle. Lipoperoxidation levels were increased (4-HNE and CL markers) instantly post-RE. LLLT prior to RE avoided the increase of the lipid peroxidation levels. Similar results were also notified for oxidation protein assays. The GPx and FRAP activities did not reduce instantly or 24 h after RE. SOD increased 24 h after RE, while CAT activity did not change with RE or LLLT. In conclusion, LLLT prior to RE reduced the oxidative stress markers, as well as, avoided reduction, and still increased the antioxidant capacity.

Measurement of Mouse Heart Rate Variability using Echocardiographic System

Aim:

We employed an echocardiographic (ECHO) system as the backbone for the collection of electrocardiogram (ECG) and heart rate variability (HRV) data. The system was tested using an exercise model in which C57 male mice were exposed to sham or forced wheel running.

Methods:

Peak/peak (RR) interval was recorded over a 3 min period using the ECG platform of the ECHO system. Isoflurane-anesthetized male mice were divided into two groups (n = 8/group): sedentary (S) and forced wheel trained (T). HRV was analyzed in time and frequency domains (Fast Fourier Transform). Exercise training (T) was performed on a motorized wheel at low intensity 1 h/day, 5 days/week, 8 weeks duration. Cardiac morphometry and function were analyzed using ECHO while ECG was the basis to measure HRV. The sampling rate was 8000 Hz. Results show that the trained mice presented a reduction in heart rate as compared to the sedentary group. This was associated with lower cardiac sympathetic and higher parasympathetic modulation leading to an improved sympathetic/parasympathetic ratio (low-frequency band/high-frequency band). The trained group showed a reduction in isovolumetric relaxation time, reduced myocardial performance index, increased relative wall thickness, and left ventricle mass when compared to the sedentary group.

Conclusion:

Results document the utility of combining the ECHO and the ECG platform, allowing for the dual measurement of autonomic and cardiac function in mice.

The impact of exercise frequency upon microvascular endothelium function and oxidative stress among patients with coronary artery disease

PURPOSE

This study compared the effects of low and high weekly exercise frequencies on microvascular endothelium function and oxidative stress among patients with coronary artery disease.

METHODS

Thirty-four male patients completed a 6-month cardiac rehabilitation programme, from which 23 performed exercise with a high frequency (HF) and 11 with a low frequency (LF). Systemic microvascular blood flow, maximal aerobic capacity, blood lipids, oxidative stress and anthropometric data were assessed prior to and after the cardiac rehabilitation programme. Microvascular blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with iontophoresis of acetylcholine.

RESULTS

Maximal aerobic capacity, biochemical analysis and anthropometric data were similar between groups prior to and after the cardiac rehabilitation programme (P>0·05). However, after 6 months of cardiac rehabilitation performed with HF, there was an increase in the peak response to acetylcholine compared with LF (83·5 ± 58·5 versus 21·8 ± 22·4%; P<0·05). Changes in lipid peroxidation (HF: -5·5 ± 9·4 versus LF: 2·2 ± 12·0 pmol MDA mg^-1 ; P = 0·19), catalase activity (HF: 0·07 ± 0·17 versus LF: 0·04 ± 0·08 U mg^-1 ; P = 0·74) and nitric oxide levels (HF: 1·8 ± 15·3 versus LF: -3·2 ± 12·3 μM; P = 0·36) were similar between groups after cardiac rehabilitation.

CONCLUSION

Six months of aerobic exercise training performed with high frequency is preferable to low frequency aiming endothelium microvascular function increases in patients with coronary artery disease. The mechanisms involved in this response are unclear and warrant additional research.

Uric Acid Level Has a J-Shaped Association with Arterial Stiffness in Korean Postmenopausal Women

Background

Uric acid has been reported to function both as an oxidant or antioxidant depending on the context. A previous study in the Korean population reported a positive linear association between serum uric acid level and arterial stiffness in men, but little is known about how serum uric acid level is related to the risk of increased arterial stiffness in Korean postmenopausal women.

Methods

We performed a cross-sectional study of 293 subjects who participated in a health examination program run by the health promotion center of Gangnam Severance Hospital between October 2007 and July 2010. High brachial-ankle pulse wave velocity was defined as a brachial-ankle pulse wave velocity of more than 1,450 cm/s. The odds ratios (ORs) for high brachial-ankle pulse wave velocity were calculated using multivariate logistic regression analysis across uric acid quartiles after adjusting for other indicators of cardiovascular risk.

Results

The 293 postmenopausal women were divided into quartiles according to uric acid level. The mean brachial-ankle pulse wave velocity values of each quartile were as follows: Q1, 1,474 cm/s; Q2, 1,375 cm/s; Q3, 1,422 cm/s; Q4, 1,528 cm/s. The second quartile was designated as the control group based on mean brachial-ankle pulse wave velocity value. Multivariate adjusted ORs (95% confidence intervals) for brachial-ankle pulse wave velocity across the uric acid quartiles were 2.642 (Q1, 1.095–6.3373), 1.00, 4.305 (Q3, 1.798–10.307), and 4.375 (Q4, 1.923–9.949), after adjusting for confounding variables.

Conclusion

Serum uric acid level has a J-shaped association with arterial stiffness in Korean postmenopausal women.

Hypertension induces additional cardiometabolic impairments and attenuates aerobic exercise training adaptations in fructose-fed ovariectomized rats

We tested whether hypertension favors the development of additional cardiometabolic changes in fructose-fed ovariectomized rats and how it affects aerobic exercise training (ET) effects. All rats received fructose in drinking water (10%) beginning at weaning, were ovariectomized at 10 weeks of age and divided into the normotensive sedentary (NFOS) and trained (NFOT) and hypertensive sedentary (HFOS) and trained (HFOT) groups. ET was performed on a treadmill. Arterial pressure (AP) was directly recorded; heart rate and AP variabilities were analyzed. Lipoperoxidation (LPO) and antioxidant enzyme levels were measured in the left ventricle. In addition to increased AP levels, when compared with the NFOS group, the hypertensive groups had resting tachycardia, a reduction of 29% in the pulse interval variance (VAR-PI), 19% in RMSSD (root mean square of successive differences, a cardiac parasympathetic index) and 53% in the α-index (spontaneous baroreflex), while the systolic AP variance (VAR-SAP) and its low-frequency band (LF-SAP) were sharply increased. ET did not alter AP levels. Even in the presence of hypertension, ET induced resting bradycardia, decreases of 33% in VAR-SAP and 49% in LF-SAP, and an increase of more than 60% in VAR-PI and the α-index. However, some of these parameters were still impaired relative to those of normotensive rats. LPO was reduced and catalase was increased in both trained groups, with no difference between the normotensive and hypertensive groups. Negative correlations were obtained between LPO and RMSSD (r=-0.60, P<0.05) and α-index (r=-0.63, P<0.05). In conclusion, hypertension augmented the dysfunctions in fructose-fed ovariectomized rats and attenuated metabolic aerobic ET benefits. These changes may be related to cardiovascular autonomic and oxidative stress alterations.

Cross platform analysis of transcriptomic data identifies ageing has distinct and opposite effects on tendon in males and females

The development of tendinopathy is influenced by a variety of factors including age, gender, sex hormones and diabetes status. Cross platform comparative analysis of transcriptomic data elucidated the connections between these entities in the context of ageing. Tissue-engineered tendons differentiated from bone marrow derived mesenchymal stem cells from young (20-24 years) and old (54-70 years) donors were assayed using ribonucleic acid sequencing (RNA-seq). Extension of the experiment to microarray and RNA-seq data from tendon identified gender specific gene expression changes highlighting disparity with existing literature and published pathways. Separation of RNA-seq data by sex revealed underlying negative binomial distributions which increased statistical power. Sex specific de novo transcriptome assemblies generated fewer larger transcripts that contained miRNAs, lincRNAs and snoRNAs. The results identify that in old males decreased expression of CRABP2 leads to cell proliferation, whereas in old females it leads to cellular senescence. In conjunction with existing literature the results explain gender disparity in the development and types of degenerative diseases as well as highlighting a wide range of considerations for the analysis of transcriptomic data. Wider implications are that degenerative diseases may need to be treated differently in males and females because alternative mechanisms may be involved.

Prevalence of metabolic syndrome and its association with lifestyle and cardiovascular biomarkers among postmenopausal women in western Algeria

OBJECTIVE

To evaluate the prevalence of metabolic syndrome (MetS), its components, and their relationship with lifestyle, inflammation, and oxidative stress among postmenopausal Algerian women.

METHODS

A prospective cross-sectional survey was conducted among postmenopausal women at a clinic in Oran, Algeria, from March 1 to June 28, 2015. A diagnosis of MetS was made using the National Cholesterol Education Program Adult Treatment Panel III guidelines. Demographic, clinical, metabolic, inflammatory, dietary, and energy variables were assessed.

RESULTS

Among 183 participants, 106 (57.9%) were diagnosed with MetS. Components of MetS included hypertension (n=144, 78.7%), hyperglycemia (n=135, 73.8%), hypertriglyceridemia (n=125, 68.3%), abdominal obesity (n=123, 67.2%), and low levels of high-density lipoprotein cholesterol (n=121, 66.1%). Although daily energy expenditure was similar among the women with or without MetS, total energy intake was increased in the group with MetS (P<0.001). The following measures were also increased among women with MetS: saturated fatty acid intake (P<0.001), C-reactive protein (P=0.051), thiobarbituric acid reactive substances (P<0.001), and carbonyls (P<0.001). By contrast, decreased monounsaturated fatty acid intake (P=0.024) and catalase activity (P<0.001) were observed in this group.

CONCLUSION

Postmenopausal status could predict MetS, with inflammation and oxidative stress arising from an unhealthy lifestyle potentially increasing cardiovascular risk.

Treating fructose-induced metabolic changes in mice with high-intensity interval training: insights in the liver, white adipose tissue, and skeletal muscle

Fructose-rich caloric sweeteners induce adverse changes in the metabolism of humans. The study evaluated the effects of high-intensity interval training (HIIT) on a fructose feeding model, focusing on the liver, white adipose tissue (WAT), skeletal muscle, and their interplay. Male C57BL/6 mice were fed for 18 wk one of the following diets: control (C; 5% of total energy from fructose) or fructose (F; 55% of total energy from fructose). In the 10th week, for an additional 8-wk period, the groups were divided into nontrained (NT) or HIIT groups, totaling four groups: C-NT, C-HIIT, F-NT, and F-HIIT. At the end of the experiment, fructose consumption in the F-NT group led to a high systolic blood pressure, high plasma triglycerides, insulin resistance with glucose intolerance, and lower insulin sensitivity. We also observed liver steatosis, adipocyte hypertrophy, and diminished gene expressions of peroxisome proliferator-activated receptor-γ coactivator 1-α and fibronectin type III domain containing 5 (FNDC5; irisin) in this F-NT group. These results were accompanied by decreased gene expressions of nuclear respiratory factor 1 and mitochondrial transcription factor A (markers of mitochondrial biogenesis), and peroxisome proliferator-activated receptor-α and carnitine palmitoyltransferase 1 (markers of β-oxidation). HIIT improved all of these data in the C-HIIT and F-HIIT groups. In conclusion, in mice fed a fructose diet, HIIT improved body mass, blood pressure, glucose metabolism, and plasma triglycerides. Liver, WAT, and skeletal muscle were positively modulated by HIIT, indicating HIIT as a coadjutant treatment for diseases affecting these tissues.NEW & NOTEWORTHY We investigated the effects of high-intensity interval training (HIIT) in mice fed a fructose-rich diet and the resulting severe negative effect on the liver, white adipose tissue (WAT), and skeletal muscle, which reduced the expression of fibronectin type III domain containing 5 (FNDC5, irisin) and PGC1α and, consequently, affected markers of mitochondrial biogenesis and β-oxidation. Because HIIT may block these adverse effects in all of these three tissues, it might be suggested that it functions as a coadjutant treatment in combatting the alterations caused by high-fructose intake.

The Coexistence of Hypertension and Ovariectomy Additively Increases Cardiac Apoptosis

To investigate whether the coexistence of hypertension and ovariectomy will increase cardiac Fas receptor and mitochondrial-dependent apoptotic pathways, histopathological analysis, the TUNEL assay and Western blotting were performed on the excised hearts from three groups of female spontaneously hypertensive rats (SHR), which were divided into a sham-operated group (SHR-Sham), bilaterally ovariectomized group (SHR-OVX) and normotensive Wistar Kyoto rats (WKY). Compared with the WKY group, the SHR-Sham group exhibited decreased protein levels of ERα, ERβ, p-Akt/Akt, Bcl-2, Bcl-xL and p-Bad and decreased further in the SHR-OVX group, as well as protein levels of t-Bid, Bak, Bad, Bax, cytochrome c, activated caspase-9 and activated caspase-3 (mitochondria-dependent apoptosis) increased in the SHR-Sham group and increased further in the SHR-OVX group. Compared with the WKY group, protein levels of Fas ligand, TNF-α, Fas death receptors, TNFR1, FADD and activated caspase-8 (Fas receptor-dependent apoptosis) increased in the SHR-Sham group, but did not increase in the SHR-OVX group, except Fas ligand and TNF-α. The coexistence of hypertension and ovariectomy attenuated the estrogen receptor survival pathway and appeared to additively increase the cardiac mitochondria-dependent, but not the Fas receptor-dependent apoptosis pathway, which might provide one possible mechanism for the development of cardiac abnormalities in hypertensive postmenopausal women.

Inflammatory Mechanisms Associated with Skeletal Muscle Sequelae after Stroke: Role of Physical Exercise

Inflammatory markers are increased systematically and locally (e.g., skeletal muscle) in stroke patients. Besides being associated with cardiovascular risk factors, proinflammatory cytokines seem to play a key role in muscle atrophy by regulating the pathways involved in this condition. As such, they may cause severe decrease in muscle strength and power, as well as impairment in cardiorespiratory fitness. On the other hand, physical exercise (PE) has been widely suggested as a powerful tool for treating stroke patients, since PE is able to regenerate, even if partially, physical and cognitive functions. However, the mechanisms underlying the beneficial effects of physical exercise in poststroke patients remain poorly understood. Thus, in this study we analyze the candidate mechanisms associated with muscle atrophy in stroke patients, as well as the modulatory effect of inflammation in this condition. Later, we suggest the two strongest anti-inflammatory candidate mechanisms, myokines and the cholinergic anti-inflammatory pathway, which may be activated by physical exercise and may contribute to a decrease in proinflammatory markers of poststroke patients.

Combined effects of aerobic exercise and l-arginine ingestion on blood pressure in normotensive postmenopausal women: A crossover study

After menopause the incidence of cardiovascular diseases increases in women. A decrease in nitric oxide (NO) bioavailability has been pointed out to play a major role in this phenomenon. Since it is believed that l-arginine administration could improve NO bioavailability, the aim of this study was to examine the effects of acute l-arginine administration associated with aerobic exercise on blood pressure (BP), redox state and inflammatory biomarkers in normotensive postmenopausal women (NPW). Sixteen volunteers (57±6yr) were subjected to four experimental sessions (crossover design): arginine+exercise (A-E); arginine (ARG); exercise+placebo (EXE); control (CON). Each session was initiated with either 9g of l-arginine ingestion (ARG or A-E days), placebo (EXE day), or nothing (CON day). The participants performed 30min of aerobic exercise (A-E and EXE days) or sitting rest (CON and ARG days). Blood samples were collected before each session and 45min after the intervention. Office BP and ambulatory blood pressure monitoring (ABPM) were evaluated. NO/cGMP pathway, redox state and inflammatory biomarkers were measured. Systolic BP decreased during the 24-hour in A-E and EXE sessions. However, diastolic BP reduced only in A-E session. No changes were found in the biomarkers concentrations. In conclusion, the association was effective in lowering diastolic BP in NPW. Additionally, physical exercise alone promoted a long lasting effect on systolic BP measured by ABPM in this population, although this beneficial effect was not associated with changes in the cardio-inflammatory biomarkers. Possibly, other factors such as neural influences could be mediating this effect.