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Obesity over-activates the classical arm of the renin-angiotensin system (RAS), impairing skeletal muscle remodeling. We aimed to compare the effect of exercise training and enalapril, an angiotensin-converting enzyme inhibitor, on RAS modulation in the skeletal muscle of obese animals. Thus, we divided C57BL/6 mice into two groups: standard chow (SC) and high-fat (HF) diet for 16 weeks. At the eighth week, the HF-fed animals were divided into four subgroups-sedentary (HF), treated with enalapril (HF-E), exercise training protocol (HF-T), and combined interventions (HF-ET). After 8 weeks of treatment, we evaluated body mass and index (BMI), body composition, exercise capacity, muscle morphology, and skeletal muscle molecular markers. All interventions resulted in lower BMI and attenuation of overactivation in the classical arm, while favoring the B2R in the bradykinin receptors profile. This was associated with reduced apoptosis markers in obese skeletal muscles. The HF-T group showed an increase in muscle mass and expression of biosynthesis markers and a reduction in expression of degradation markers and muscle fiber atrophy due to obesity. These findings suggest that the combination intervention did not have a synergistic effect against obesity-induced muscle remodeling. Additionally, the use of enalapril impaired muscle's physiological adaptations to exercise training., (© 2024 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Altered methionine metabolism is associated with weight gain in obesity. The methionine adenosyltransferase (MAT), catalyzing the first reaction of the methionine cycle, plays an important role regulating lipid metabolism. However, its role in obesity, when a plethora of metabolic diseases occurs, is still unknown. By using antisense oligonucleotides (ASO) and genetic depletion of Mat1a, here, we demonstrate that Mat1a deficiency in diet-induce obese or genetically obese mice prevented and reversed obesity and obesity-associated insulin resistance and hepatosteatosis by increasing energy expenditure in a hepatocyte FGF21 dependent fashion. The increased NRF2-mediated FGF21 secretion induced by targeting Mat1a, mobilized plasma lipids towards the BAT to be catabolized, induced thermogenesis and reduced body weight, inhibiting hepatic de novo lipogenesis. The beneficial effects of Mat1a ASO were abolished following FGF21 depletion in hepatocytes. Thus, targeting Mat1a activates the liver-BAT axis by increasing NRF2-mediated FGF21 secretion, which prevents obesity, insulin resistance and hepatosteatosis., (© 2022. The Author(s).)

The obstructive sleep apnea syndrome (OSA) is a clinical entity characterized by recurring episodes of apnea and/or hypopnea during sleep, due to a total or partial collapse, respectively, of the upper airway. This collapse originates a set of pathophysiological changes that determine the appearance of several cardiovascular complications. OSA contributes for the development of hypertension, heart failure, arrhythmias and coronary heart disease. Nowadays it is recognized to be an important public health problem, taking into account not just its repercussions but also its prevalence, since the main risk factor for the disease is obesity, a growing problem worldwide, both in developed and developing countries. The present review summarizes the current knowledge about OSA, as regards its definition, pathophysiology, clinical manifestations, diagnosis, cardiovascular effects and treatment., (Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.)

The aim of this study was to evaluate whether high-fat (HF) diet intake during puberty can program obesity as well as generate glucose imbalance and hepatic metabolic dysfunctions in adult life. Male Wistar rats were randomly assigned into two groups: rats fed standard chow (NF) and rats fed a HF from postnatal 30-day-old (PND30) until PND60. Then, both groups were fed a standard chow from PND60 until PND120. Euthanasia and samples collections occurred at PND120. HF animals were overweight (+11%) and had increased adiposity, hyperphagia (+12%), hyperglycaemia (+13%), hyperinsulinemia (+69%), and hypertriglyceridemia (+34%). Plasma glucose levels during intravenous glucose tolerance test (ivGTT) and intraperitoneal insulin tolerance test (ipITT) were also higher in the HF group, whereas Kitt was significantly lower (–34%), suggesting reduced insulin sensitivity. In the same sense, HF animals present pancreatic islets hypertrophy and high β-cell mass. HF animals also had a significant increase in blood glucose levels during pyruvate tolerance test, indicating increased gluconeogenesis. Hepatic morphology analyses showed an increase in lipid inclusion in the HF group. Moreover, PEPCK and FAS protein expression were higher in the livers of the HF animals (+79% and + 37%, respectively). In conclusion, HF during puberty causes obese phenotype leading to glucose dyshomeostasis and nonalcoholic fatty liver disease, which can be related to the overexpression of proteins PEPCK and FAS. [ABSTRACT FROM AUTHOR]

Bisphenol S (BPS) is widely used in the manufacture products and increase the risk of cardiovascular diseases. The effect of the association between obesity and BPS on cardiac outcomes is still unknown. Male C57BL/6 mice were divided into standard chow diet (SC; 15 kJ/g), standard chow diet + BPS (SCB), high-fat diet (HF; 21 kJ/g), and high-fat diet + BPS (HFB). Over 12 weeks, the groups were exposed to BPS through drinking water (dose: 25 μg/kg/day) and/or a HF diet. We evaluated: body mass (BM), total cholesterol, systolic blood pressure (SBP), left ventricle (LV) mass, and cardiac remodeling. In the SCB group, BM, total cholesterol, and SBP increase were augmented in relation to the SC group. In the HF and HFB groups, these parameters were higher than in the SC and SCB groups. Cardiac hypertrophy was evidenced by augmented LV mass and wall thickness, and ANP protein expression in all groups in comparison to the SC group. Only the HFB group had a thicker LV wall than SCB and HF groups, and increased cardiomyocyte area when compared with SC and SCB groups. Concerning cardiac fibrosis, SCB, HF, and HFB groups presented higher interstitial collagen area, TGFβ, and α-SMA protein expression than the SC group. Perivascular collagen area was increased only in the HF and HFB groups than SC group. Higher IL-6, TNFα, and CD11c protein expression in all groups than the SC group evidenced inflammation. All groups had elevated CD36 and PPARα protein expression in relation to the SC group, but only HF and HFB groups promoted cardiac steatosis with increased perilipin 5 protein expression than the SC group. BPS exposure alone promoted cardiac remodeling with pathological concentric hypertrophy, fibrosis, and inflammation. Diet-induced remodeling is aggravated when associated with BPS, with marked hypertrophy, alongside fibrosis, inflammation, and lipid accumulation. [Display omitted] • Bisphenol S increases systolic blood pressure. • Bisphenol S promotes cardiac hypertrophy, fibrosis, and inflammation. • High-fat diet-induced cardiac hypertrophy is worsened by Bisphenol S exposure. [ABSTRACT FROM AUTHOR]

This study investigated whether regulation of the renin–angiotensin system (RAS) by enalapril and/or aerobic exercise training (AET) causes browning of the subcutaneous white adipose tissue (sWAT). C57BL/6 mice were fed either a standard chow or a high‐fat (HF) diet for 16 weeks. At Week 8, HF‐fed animals were divided into sedentary (HF), enalapril (HF‐E), AET (HF‐T), and enalapril plus AET (HF‐ET) groups. Subsequently, sWAT was extracted for morphometry, determination of RAS expression, and biomarkers of WAT browning. The HF group displayed adipocyte hypertrophy and induction of the classical RAS axis. Conversely, all interventions reduced adiposity and induced the counterregulatory RAS axis. However, only AET raised plasma irisin, increased peroxisome proliferator‐activated receptor‐γ coactivator‐1α, and uncoupling protein‐1 levels, and the expression of PR‐domain containing 16 in sWAT. Therefore, we concluded that AET‐induced sWAT browning was independent of the counterregulatory axis shifting of RAS in HF diet‐induced obesity. [ABSTRACT FROM AUTHOR]

Overactivation of the classical arm of the renin-angiotensin (Ang) system (RAS) occurs during inflammation, oxidative stress and obesity-induced cardiomyopathy. The activation of the protective arm of RAS may act to counterbalance the deleterious effects of the classical RAS. Although aerobic exercise training (AET) shifts the balance of the RAS towards the protective arm, little is known about the molecular adaptations to different volumes of AET. The aim of this study was to evaluate the impact of AET volume on the modulation of RAS, as well as on cardiac biomarkers of oxidative stress and inflammation, in a diet-induced obesity model. Male Wistar rats were fed either control (CON) or high fat (HF) diet for 32 weeks. At week 20, HF group was subdivided into sedentary, low (LEV, 150 min/week) or high (HEV, 300 min/week) exercise volume. After 12 weeks of exercise, body mass gain, systolic blood pressure and heart rate were evaluated, as well as RAS, oxidative stress and inflammation in the heart. Body mass gain, systolic blood pressure and heart rate were higher in HF group when compared with SC group. Both trained groups restored systolic blood pressure and heart rate, but only HEV reduced body mass gain. Regarding the cardiac RAS, the HF group exhibited favoring of the classical arm and both trained groups shifted the balance towards the counterregulatory protective arm. The HF group had higher B1R expression and lower B2R expression than the control group, and B2R expression was reverted in both trained groups. The HF group also presented oxidative stress. The LEV and HEV groups improved the cardiac redox status by reducing Nox 2 and nitrotyrosine expression, but only the LEV group was able to increase the antioxidant defense by increasing Nrf2 signaling. While the HF group presented higher TNF-α, IL-6 and NFκB expression, and lower IL-10 expression, than the SC group, both training protocols improved the inflammatory profile. Although both trained groups improved the deleterious changes related to obesity cardiomyopathy, it is clear that the molecular mechanisms differ between them. Our results suggest that different exercise volumes might reach different molecular targets, and this could be a relevant factor when using exercise to manage obesity. • Obesity increased cardiac inflammation, oxidative stress and ACE/AT1R activation. • 12 weeks of two different exercise volume protocols were tested for its benefits on the heart. • Both training volumes reduced Nox2 expression, nitrosative damage, and inflammation. • Increased Nrf2 signaling was observed with 150 min, but not 300 min of weekly exercise. • Higher exercise volume favored the alternative arm of renin angiotensin system. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress poses a new pathological mechanism for metabolic-associated fatty liver disease (MAFLD). MAFLD treatment has encompassed renin-angiotensin system (RAS) blockers and aerobic exercise training, but their association with hepatic ER stress is not well known. Therefore, we aimed to compare the effects of hepatic RAS modulation by enalapril and/or aerobic exercise training over ER stress in MAFLD caused by a diet-induced obesity model. C57BL/6 mice were fed a standard-chow (CON, n = 10) or a high-fat (HF, n = 40) diet for 8 weeks. HF group was then randomly divided into: HF (n = 10), HF + Enalapril (EN, n = 10), HF + Aerobic exercise training (AET, n = 10), and HF + Enalapril+Aerobic exercise training (EN + AET, n = 10) for 8 more weeks. Body mass (BM) and glucose profile were evaluated. In the liver, ACE and ACE2 activity, morphology, lipid profile, and protein expression of ER stress and metabolic markers were assessed. Both enalapril and aerobic exercise training provided comparable efficacy in improving diet-induced MAFLD through modulation of RAS and ER stress, but the latter was more efficient in improving ER stress, liver damage and metabolism. This is the first study to evaluate pharmacological (enalapril) and non-pharmacological (aerobic exercise training) RAS modulators associated with ER stress in a diet-induced MAFLD model. HF diet led to favoring of the RAS classical arm and increased ER stress through higher expression of the eIF2α pathway. These results could be related to HF diet-associated insulin resistance and upregulation of gluconeogenesis enzymes PEPCK and G6Pase, as well as lipid accumulation through increased lipogenic transcription factor SREBP1c and lower PPARα levels. Enalapril treatment, aerobic exercise training, and the combination of both interventions were able to favor the RAS counterregulatory arm, improve ER stress and decrease lipid accumulation. All interventions were also able to improve insulin resistance, although aerobic exercise training showed more efficiency, reverting glucose intolerance and decreasing the expression of PEPCK. Aerobic exercise training was also the only intervention able to reduce binucleation of hepatocytes and the association with enalapril treatment reverted the increase in hepatocytes with two or more nuclei, which could be suggestive of liver damage associated with the pharmacological treatment. [Display omitted] • Enalapril and aerobic exercise training decrease ACE/ACE2 ratio in obese mice. • RAS counterregulatory arm could be associated to decreased ER stress markers in MAFLD. • Aerobic exercise training better improved liver ER stress markers, metabolism and damage. [ABSTRACT FROM AUTHOR]

Obesity-related metabolic diseases occur as a result of disruptions in white adipose tissue (WAT) plasticity, especially through visceral fat accumulation and adipocyte hypertrophy. This study aimed to evaluate the impact of renin–angiotensin system (RAS) and bradykinin receptors modulation by enalapril treatment and/or exercise training on WAT morphology and related deleterious outcomes. Male C57BL/6 mice were fed either a standard chow or a high-fat (HF) diet for 16 weeks. At the 8th week, HF-fed animals were divided into sedentary (HF), enalapril treatment (HF-E), exercise training (HF-T), and enalapril treatment plus exercise training (HF-ET) groups. Following the experimental protocol, body mass gain, adiposity index, insulin resistance, visceral WAT morphometry, renin-angiotensin system, and bradykinin receptors were evaluated. The HF group displayed increased adiposity, larger visceral fat mass, and adipocyte hypertrophy, which was accompanied by insulin resistance, overactivation of Ang II/AT1R arm, and favoring of B1R in bradykinin receptors profile. All interventions ameliorated visceral adiposity and related outcomes by favoring the Ang 1–7/MasR arm and the B2R expression in B1R/B2R ratio. However, combined therapy additively reduced Ang II/Ang 1–7 ratio. Our results suggest that Ang 1–7/MasR arm and B2R activation might be relevant targets in the treatment of visceral obesity. • Enalapril treatment and exercise training ameliorates visceral adiposity. • Visceral adiposity is related to Ang II/AT1R and B1R overexpression in vWAT. • The interventions favor the counterregulatory arm of visceral adipose RAS. • Combined therapy additively reduces Ang II/Ang 1–7 ratio in vWAT. • The interventions shift the bradykinin receptor profile towards B2R in vWAT. [ABSTRACT FROM AUTHOR]

Objectives: Lately, many countries have restricted or even banned transfat, and palm oil has become a preferred replacement for food manufacturers. Whether palm oil is potentially an unhealthy food mainly due to its high content of saturated Palmitic Acid (PA) is a matter of debate. The aim of this study was to test whether qualitative aspects of diet such as levels of PA and the fat source are risk factors for Metabolic Syndrome (MS) and Metabolic Associated Fatty Liver Disease (MAFLD). Methods: C57BL/6 male mice were fed for 14 weeks with three types of Western diet (WD): 1. LP-WD—low concentration of PA (main fat source—corn and soybean oils); 2. HP-WD—high concentration of PA (main fat source—palm oil); 3. HP-Trans-WD—high concentration of PA (mainly transfat). Results: All types of WD caused weight gain, adipocyte enlargement, hepatomegaly, lipid metabolism alterations, and steatohepatitis. Feeding with HP diets led to more prominent obesity, hypercholesterolemia, stronger hepatic injury, and fibrosis. Only the feeding with HP-Trans-WD resulted in glucose intolerance and elevation of serum transaminases. Brief withdrawal of WDs reversed MS and signs of MAFLD. However, mild hepatic inflammation was still detectable in HP groups. Conclusions: HP and HP-Trans-WD play a crucial role in the genesis of MS and MAFLD. [ABSTRACT FROM AUTHOR]

To compare the effect of 150 min vs. 300 min of weekly moderate intensity exercise training on the activation of the opioid system and apoptosis in the hearts of a diet-induced obesity model. Male Wistar rats were fed with either control (CON) or high fat (HF) diet for 32 weeks. At the 20th week, HF group was subdivided into sedentary, low (LEV, 150 min·week−1) or high (HEV, 300 min·week−1) exercise volume. After 12 weeks of exercise, body mass gain, adiposity index, systolic blood pressure, cardiac morphometry, apoptosis biomarkers and opioid system expression were evaluated. Sedentary animals fed with HF presented pathological cardiac hypertrophy and higher body mass gain, systolic blood pressure and adiposity index than control group. Both exercise volumes induced physiological cardiac hypertrophy, restored systolic blood pressure and improved adiposity index, but only 300 min·week−1 reduced body mass gain. HF group exhibited lower proenkephalin, PI3K, ERK and GSK-3β expression, and greater activated caspase-3 expression than control group. Compared to HF, no changes in the cardiac opioid system were observed in the 150 min·week−1 of exercise training, while 300 min·week−1 showed greater proenkephalin, DOR, KOR, MOR, Akt, ERK and GSK-3β expression, and lower activated caspase-3 expression. 300 min·week−1 of exercise training triggered opioid system activation and provided greater cardioprotection against obesity than 150 min·week−1. Our findings provide translational aspect with clinical relevance about the critical dose of exercise training necessary to reduce cardiovascular risk factors caused by obesity. [ABSTRACT FROM AUTHOR]

Postnatal early overfeeding (PO) is a risk factor for cardiometabolic disorders. However, remains unknown the cardiac effects in the second generation from postnatal overfed dams. Our aim was to investigate the effects of maternal PO on cardiac parameters in second generation (F2) offspring. For this, pregnant Wistar rats (F0) were divided into two groups: normal litter (NL, 9 pups) and small litter (SL, 3 pups). At P70, female offspring (F1) of both groups were mated with non-PO male rats. At P21 male and female F2 offspring (NLO and SLO) were weaned, and at P45 they were euthanized to evaluate the cardiac function and sample collection. Male and female SLO showed increased body weight, food intake and adiposity. Blood estradiol levels were increased in the male SLO and decreased in the female SLO. Blood testosterone levels increased in SLO females, but not change in SLO male rats. Although SLO offspring presented cardiac hypertrophy, only males had ex vivo functional impairments, such as reduction of the intraventricular systolic pressure and dP/dt. Male and female SLO had increased interstitial fibrosis; however, only the male SLO had increased perivascular fibrosis. In addition, only male rats from SLO group had decreased AKT and Type 2 Ang-2 receptor, increased catalase and type alpha estrogenic receptor protein levels. Maternal PO leads to obese phenotype and alters sex-steroid levels in both male and female offspring. Although both sexes showed cardiac hypertrophy, only male offspring showed cardiac dysfunction, which may be related with Ang2 and AKT signaling impairments. [ABSTRACT FROM AUTHOR]