Central and peripheral effects of physical exercise without weight reduction in obese and lean mice

Habitual physical activity minimizes healthcare costs resulting from comorbidities among adults with cardiovascular diseases

BACKGROUND

Habitual physical activity (HPA) can be used as a non-pharmacological strategy to prevent and control chronic diseases, as well as playing a role in minimizing healthcare costs.

OBJECTIVE

To verify the impact of HPA on healthcare costs at different levels of care, over 24 months, in an adult population with cardiovascular diseases (CVD), including individuals with or without comorbidities.

METHODS

Two-hundred and seventy-eight adults with CVD, aged between 30 and 65 years, participated in the study. Information on healthcare costs was obtained from medical records and included primary, secondary, and tertiary levels. Comorbidities such as diabetes, dyslipidemia, arterial hypertension, and obesity were registered. HPA was measured using the Baecke questionnaire. Comparisons between groups were performed using Student's t (

RESULTS

The presence of comorbidities increased healthcare costs (p<0.05). HPA provided savings ranging from US$ 22.5/24 months to US$ 63.9/24 months with primary healthcare services, regardless of the presence of comorbidities.

CONCLUSION

Considering adults with CVD, HPA significantly minimizes healthcare costs in the primary care in Brazil, even in the presence of comorbidities, such as diabetes, dyslipidemia, arterial hypertension, and obesity.

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Key Words

• Brazilian national health system
• Exercise
• Obesity
• Primary health care

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MESH Headings

• Adult
• Humans
• Middle Aged
• Aged
• Cardiovascular Diseases/epidemiology
• Health Care Costs
• Obesity
• Hypertension
• Diabetes Mellitus
• Exercise
• Dyslipidemias

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Affiliation(s)

Monique Yndawe Castanho Araujo Post-graduation Program in Movement Sciences, Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil; Group of Studies in Health, Physical Activity, and Economy (GESAFE), Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil.
Eduardo Kokubun Post-graduation Program in Movement Sciences, Universidade Estadual Paulista (UNESP), Rio Claro, São Paulo, Brazil
Maria Carolina Castanho Saes Norberto Post-graduation Program in Movement Sciences, Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil; Group of Studies in Health, Physical Activity, and Economy (GESAFE), Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil
André Lucas Servo Bento Group of Studies in Health, Physical Activity, and Economy (GESAFE), Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil
Bruna Camilo Turi-Lynch Department of Physical Education and Exercise Science, Lander University, Greenwood, South Carolina, USA
Jamile Sanches Codogno Post-graduation Program in Movement Sciences, Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil; Group of Studies in Health, Physical Activity, and Economy (GESAFE), Universidade Estadual Paulista (UNESP), Presidente Prudente, São Paulo, Brazil

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NPFFR2-deficient mice fed a high-fat diet develop strong intolerance to glucose

A previous study on neuropeptide FF receptor 2 (NPFFR2)-deficient mice has demonstrated that NPFFR2 is involved in the control of energy balance and thermogenesis. Here, we report on the metabolic impact of NPFFR2 deficiency in male and female mice that were fed either a standard diet (STD) or a high-fat diet (HFD) and each experimental group consisted of ten individuals. Both male and female NPFFR2 knockout (KO) mice exhibited severe glucose intolerance that was exacerbated by a HFD diet. In addition, reduced insulin pathway signaling proteins in NPFFR2 KO mice fed a HFD resulted in the development of hypothalamic insulin resistance. HFD feeding did not cause liver steatosis in NPFFR2 KO mice of either sex, but NPFFR2 KO male mice fed a HFD had lower body weights, white adipose tissues, and liver and lower plasma leptin levels compared with their wild-type (WT) controls. Lower liver weight in NPFFR2 KO male mice compensated for HFD-induced metabolic stress by increased liver PPARα and plasma FGF21 hepatokine, which supported fatty acid β-oxidation in the liver and white adipose tissue. Conversely, NPFFR2 deletion in female mice attenuated the expression of Adra3β and Pparγ, which inhibited lipolysis in adipose tissue.

Comorbidities do not mitigate the effect of habitual physical activity on the reduction of healthcare costs among adults with cardiovascular diseases: A mediation analysis

BACKGROUND

Habitual Physical activity (HPA) is a non-pharmacological strategy to prevent and control chronic diseases, and it plays an important role in minimizing healthcare costs.

OBJECTIVES

This study aimed to investigate the relationship between HPA and healthcare costs from the perspective of the Brazilian National Healthcare System, and to establish the mediating role of comorbidities in this relationship among patients with cardiovascular diseases (CVD).

DESIGN AND SETTING

This longitudinal study was conducted in a medium-sized Brazilian city and included 278 participants assisted by the Brazilian National Healthcare System.

METHODS

Information on healthcare costs were obtained from medical records and included primary, secondary, and tertiary levels. Comorbidities (diabetes, dyslipidemia, and arterial hypertension) were self-reported, and obesity was confirmed with the percentage of body fat. HPA was measured using a questionnaire (Baecke questionnaire). Face-to-face interviews provided information on sex, age, and education level. Statistical analysis included linear regression and Structural Equation Modeling, significance was set at 5 % and the Stata software (version 16.0) was used to perform the analysis.

RESULTS

The sample included 278 adults with a mean age of 54.49 (8.32) years. For each score of HPA, there was a reduction in healthcare costs of US$ 83.99/_{24 months} (95 % CI: - 159.15; - 8.84), and the sum of comorbidities did not mediate this relationship.

CONCLUSION

It is concluded that healthcare costs seem to be affected by HPA among patients with CVD, while this phenomenon seems not to be mediated by the sum of comorbidities.

Productivity Loss, Healthcare Costs, and Habitual Physical Activity Among Adults With Cardiovascular Diseases

OBJECTIVES

The aims of the study are to quantify the relationship between productivity loss and healthcare costs among adults with cardiovascular diseases and also to verify whether habitual physical activity (HPA) modulates this relationship.

METHODS

Information was obtained about healthcare costs, productivity loss, and HPA.

RESULTS

The sample consisted of 278 adults. Active workers who reported presenteeism and absenteeism due to cardiovascular diseases had higher direct costs ( P < 0.05) than those who reported other reasons. Those who reported absenteeism spent US $187.33 more on healthcare services annually than those who did not miss work because of health reasons. However, an annual savings of US $53.00 was observed for each increase in the score of HPA.

CONCLUSIONS

There was a positive correlation between absenteeism and direct healthcare costs among adults with cardiovascular diseases, and HPA positively affected this relationship.

Acute physical exercise increases PI3K-p110α protein content in the hypothalamus of obese mice

The anatomy of the hypothalamus includes many nuclei and a complex network of neurocircuits. In this context, some hypothalamic nuclei reside closer to the blood-brain barrier, allowing communication with the peripheral organs through some molecules, such as leptin. Leptin is considered the main adipokine for energy homeostasis control. Furthermore, leptin signalling in the hypothalamus can communicate with insulin signalling through the activation of phosphoinositide 3-kinase (PI3k). Previous data suggest that isoforms of PI3k are necessary to mediate insulin action in the hypothalamus. However, obese animals show impairment in the central signalling of these hormones. Thus, in the current study, we evaluated the role of acute exercise in the leptin and insulin pathways in the hypothalamus, as well as in food intake control in obese mice. Although acute physical exercise was not able to modulate leptin signalling, this protocol suppressed the increase in the suppressor of cytokine signalling 3 (SOCS3) protein levels. In addition, acute exercise increased the content of PI3k-p110α protein in the hypothalamus. The exercised animals showed a strong tendency to reduction in cumulative food intake. For the first time, our results indicate physical exercise can increase PI3k-p110α protein content in the hypothalamus of obese mice and regulate food intake.

Physical exercise promotes brain remodeling by regulating epigenetics, neuroplasticity and neurotrophins

Exercise has been shown to have beneficial effects on brain functions in humans and animals. Exercise can improve memory and learning in age-related neurodegenerative diseases. In animal models, physical exercise regulates epigenetics, promotes synaptic plasticity and hippocampal neurogenesis, regulates the expression levels of neurotrophic factors, and improves cognitive function. Therefore, exercise is very important for brain rehabilitation and remodeling. The purpose of this review is to explore the mechanisms by which exercise exerts positive effects on brain function. This knowledge implies that physical exercise can be used as a non-drug therapy for neurological diseases.

Delayed Exercise Training Improves Obesity-Induced Chronic Kidney Disease by Activating AMPK Pathway in High-Fat Diet-Fed Mice

Exercise training is now recognized as an interesting therapeutic strategy in managing obesity and its related disorders. However, there is still a lack of knowledge about its impact on obesity-induced chronic kidney disease (CKD). Here, we investigated the effects of a delayed protocol of endurance exercise training (EET) as well as the underlying mechanism in obese mice presenting CKD. Mice fed a high-fat diet (HFD) or a low-fat diet (LFD) for 12 weeks were subsequently submitted to an 8-weeks EET protocol. Delayed treatment with EET in obese mice prevented body weight gain associated with a reduced calorie intake. EET intervention counteracted obesity-related disorders including glucose intolerance, insulin resistance, dyslipidaemia and hepatic steatosis. Moreover, our data demonstrated for the first time the beneficial effects of EET on obesity-induced CKD as evidenced by an improvement of obesity-related glomerulopathy, tubulo-interstitial fibrosis, inflammation and oxidative stress. EET also prevented renal lipid depositions in the proximal tubule. These results were associated with an improvement of the AMPK pathway by EET in renal tissue. AMPK-mediated phosphorylation of ACC and ULK-1 were particularly enhanced leading to increased fatty acid oxidation and autophagy improvement with EET in obese mice.

Compensatory eating behaviors in male and female rats in response to exercise training

Exercise is often used as a strategy for weight loss maintenance. In preclinical models, we have shown that exercise may be beneficial because it counters the biological drive to regain weight. However, our studies have demonstrated sex differences in the response to exercise in this context. In the present study, we sought to better understand why females and males exhibit different compensatory food eating behaviors in response to regular exercise. Using a forced treadmill exercise paradigm, we measured weight gain, energy expenditure, food intake in real time, and the anorectic effects of leptin. The 4-wk exercise training resulted in reduced weight gain in males and sustained weight gain in females. In male rats, exercise decreased intake, whereas it increased food intake in females. Our results suggest that the anorectic effects of leptin were not responsible for these sex differences in appetite in response to exercise. If these results translate to the human condition, they may reveal important information for the use and application of regular exercise programs.

The TRPV1 channel regulates glucose metabolism

Endocannabinoids (ECs) mediate effects via cannabinoid receptor types 1 and 2 (CB1 and 2) and transient receptor potential channel-vanilloid subfamily member 1 (TRPV1) channels. In high-fat diet (HFD)-induced obese mice overactivity of the EC system and inhibition of CB1 increase skeletal muscle glucose uptake. We explored the role of TRPV1. Male TRPV1^+/+(WT) and TRPV1^-/-(KO)-mice were fed (20 wk) a standard laboratory diet (SLD) or HFD. An intraperitoneal glucose tolerance test was performed. RT-PCR was performed to measure mRNA of genes involved in glucose/lipid metabolism and the EC system in soleus (SOL) and extensor digitorum longus (EDL) muscles. Cultured L6 cells were used to measure glucose uptake in skeletal muscle. HFD mice weighed more and had higher insulin levels than SLD mice, with no genotype differences. Basal and peak glucose were higher in HFD mice irrespective of genotype, but glucose cleared faster in HFD WT vs. HFD KO-mice. 2-Arachidonoylglycerol augmented insulin-induced glucose uptake in skeletal L6-cells, an effect blocked by the TRPV1 antagonist SB-366791. In EDL, fatty acid amide hydrolase (FAAH) mRNA was increased in KO vs. WT mice, irrespective of diet. Pyruvate dehydrogenase kinase isozyme 4 (PDK4) and mitochondrial uncoupling protein 3 (UCP3) were elevated and FA desaturase 2 (FADS2) mRNA lower in HFD mice, irrespective of genotype. CB1 and stearoyl-CoA desaturase 1 (SCD1) were lower in HFD WT mice only. In SOL, PDK4, UCP3, hormone-sensitive lipase (LIPE), fatty acid translocase (CD36), and carnitine palmitoyl transferase 2 (CPT2) were elevated and SCD1, FAAH, FADS2, and Troponin 1 (TNNC1) mRNA lower in HFD mice, irrespective of genotype. In conclusion, TRPV1 regulates glucose disposal in HFD mice. We propose that TRPV1 plays a role in coordinating glucose metabolism in EDL under conditions of metabolic stress.

Role of orexin in exercise-induced leptin sensitivity in the mediobasal hypothalamus of mice

Orexin is known as an important neuropeptide in the regulation of energy metabolism. However, the role of orexin in exercise-induced leptin sensitivity in the hypothalamus has been unclear. In this study, we determined the effect of transient treadmill exercise on leptin sensitivity in the mediobasal hypothalamus (MBH) of mice and examined the role of orexin in post-exercise leptin sensitivity. Treadmill running for 45 min increased the orexin neuron activity in mice. Intraperitoneal injection of a submaximal dose of leptin after exercise stimulated the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in MBH of mice post-exercise compared with that in non-exercised mice, although intracerebroventricular (icv) injection of leptin did not enhance STAT3 phosphorylation, even after exercise. Icv injection of an orexin receptor antagonist, SB334867 reduced STAT3 phosphorylation, which was enhanced by icv injection of orexin but not by direct injection of orexin into MBH. Exercise increased the phosphorylation of extracellular signal-regulated kinases (ERKs) in the MBH of mice, while ERK phosphorylation was reduced by SB334867. Leptin injection after exercise increased the leptin level in MBH, whereas icv injection of SB334867 suppressed the increase in the leptin level in MBH of mice. These results indicate that the activation of orexin neurons by exercise may contribute to the enhancement of leptin sensitivity in MBH. This effect may be mediated by increased transportation of circulating leptin into MBH, with the involvement of ERK phosphorylation.

Voluntary wheel running reduces weight gain in mice by decreasing high-fat food consumption

We investigated whether wheel running for just 30 min on 5 days each week, an exercise routine based on recommended levels of physical activity for adults, regulates body weight and food intake in mice. Male C57BL/6 mice were divided into groups and given ad libitum access to high-fat food and standard chow or standard chow only. For 30 min on 5 days each week, mice were treated with an in-cage running wheel which was either open to allow voluntary exercise or locked and could not rotate for control. Wheel running reduced weight gain and fat mass among mice fed high-fat food and standard chow, but not mice fed standard chow only. Wheel running decreased high-fat food consumption. Standard chow intake was unchanged. Mice provided with a locked running wheel but pair-fed the same amount of food as wheel running mice also displayed reduced weight gain and fat mass. We conclude that voluntary wheel running for 30 min on 5 days each week reduced weight gain and fat mass in mice by preferentially decreasing high-fat food intake. This model of voluntary wheel running can be used to investigate mechanisms underlying the benefits of exercise on body weight and food intake, informing obesity intervention strategies for humans.

Adiponectin-Consideration for its Role in Skeletal Muscle Health

Adiponectin regulates metabolism through blood glucose control and fatty acid oxidation, partly mediated by downstream effects of adiponectin signaling in skeletal muscle. More recently, skeletal muscle has been identified as a source of adiponectin expression, fueling interest in the role of adiponectin as both a circulating adipokine and a locally expressed paracrine/autocrine factor. In addition to being metabolically responsive, skeletal muscle functional capacity, calcium handling, growth and maintenance, regenerative capacity, and susceptibility to chronic inflammation are all strongly influenced by adiponectin stimulation. Furthermore, physical exercise has clear links to adiponectin expression and circulating concentrations in healthy and diseased populations. Greater physical activity is generally related to higher adiponectin expression while lower adiponectin levels are found in inactive obese, pre-diabetic, and diabetic populations. Exercise training typically restores plasma adiponectin and is associated with improved insulin sensitivity. Thus, the role of adiponectin signaling in skeletal muscle has expanded beyond that of a metabolic regulator to include several aspects of skeletal muscle function and maintenance critical to muscle health, many of which are responsive to, and mediated by, physical exercise.

High-fat Diet and Physical Exercise Differentially Modulate Adult Neurogenesis in the Mouse Hypothalamus

The hypothalamus has emerged as a novel neurogenic niche in the adult brain during the past decade. However, little is known about its regulation and the role hypothalamic neurogenesis might play in body weight and appetite control. High-fat diet (HFD) has been demonstrated to induce an inflammatory response and to alter neurogenesis in the hypothalamus and functional outcome measures, e.g. body weight. Such modulation poses similarities to what is known from adult hippocampal neurogenesis, which is highly responsive to lifestyle factors, such as nutrition or physical exercise. With the rising question of a principle of neurogenic stimulation by lifestyle in the adult brain as a physiological regulatory mechanism of central and peripheral functions, exercise is interventionally applied in obesity and metabolic syndrome conditions, promoting weight loss and improving glucose tolerance and insulin sensitivity. To investigate the potential pro-neurogenic cellular processes underlying such beneficial peripheral outcomes, we exposed adult female mice to HFD together with physical exercise and evaluated neurogenesis and inflammatory markers in the arcuate nucleus (ArcN) of the hypothalamus. We found that HFD increased neurogenesis, whereas physical exercise stimulated cell proliferation. HFD also increased the amount of microglia, which was counteracted by physical exercise. Physiologically, exercise increased food and fat intake but reduced HFD-induced body weight gain. These findings support the hypothesis that hypothalamic neurogenesis may represent a counter-regulatory mechanism in response to environmental or physiological insults to maintain energy balance.