RESUMO
The classical renin angiotensin aldosterone system (RAAS), as well as the recently described counter-regulatory or non-canonical RAAS have been well characterized for their role in cardiovascular homeostasis. Moreover, extensive research has been conducted over the past decades on both paracrine and the endocrine roles of local RAAS in various metabolic regulations and in chronic diseases. Clinical evidence from patients on RAAS blockers as well as pre-clinical studies using rodent models of genetic manipulations of RAAS genes documented that this system may play important roles in the interplay between metabolic diseases and cancer, namely breast cancer. Some of these studies suggest potential therapeutic applications and repurposing of RAAS inhibitors for these diseases. In this review, we discuss the mechanisms by which RAAS is involved in the pathogenesis of metabolic diseases such as obesity and type-2 diabetes as well as the role of this system in the initiation, expansion and/or progression of breast cancer, especially in the context of metabolic diseases.
Assuntos
Neoplasias da Mama , Homeostase , Doenças Metabólicas , Sistema Renina-Angiotensina , Humanos , Sistema Renina-Angiotensina/fisiologia , Neoplasias da Mama/metabolismo , Animais , Homeostase/fisiologia , Doenças Metabólicas/metabolismo , Feminino , Equilíbrio Hidroeletrolítico/fisiologia , Pressão Sanguínea/fisiologiaRESUMO
PURPOSE OF REVIEW: Sports nutrition (SN) is pivotal in aiding athletes to reach peak performance, minimize sport-related injuries, enhance career longevity, and improve general health. An accurate assessment of athletes' sports nutrition knowledge (SNK) is required to design targeted nutrition education programs aimed at enhancing both nutritional knowledge and dietary practices. This review systematically evaluates studies that use questionnaires to assess the SNK of athletes engaged in athletics. RECENT FINDINGS: The literature search was conducted in PubMed®, Web of Science®, and Scopus®, and 375 potentially relevant articles were identified. The total number of articles included in the present review is 11, with eight studies involving only athletic disciplines and three involving athletics and other sports. The majority (n = 8) of the questionnaires included general and SN aspects, with SN covering endurance athletes' knowledge of competition carbohydrate guidelines, gastrointestinal symptoms associated with exercise, and ultra-endurance athletes' sodium beliefs and practices. Questionnaires were either delivered online (n = 7) or self-administered in hard copy (n = 1). The three major strategies identified for developing questionnaires were based on previous literature and recent SN guidelines (n = 6), consultation with a panel of experts (n = 7), and the use of a previously developed sports nutrition knowledge questionnaires (SNKQ) (n = 4), with more than one approach used in five studies. Similarly, up to three validation approaches were used, including content, face, and construct validity. Seven studies used a test-retest procedure to ensure external reliability, and eight used Cronbach's alpha or kappa coefficient to assess internal consistency. Endurance and ultra-endurance athletes are the populations of interest for the majority of questionnaires developed for athletics, with most questionnaires incorporating general and SNK topics.
Assuntos
Ciências da Nutrição e do Esporte , Esportes , Humanos , Reprodutibilidade dos Testes , Atletas , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Alzheimer's disease (AD) is an age-related neurodegenerative disease characterized by amyloid-ß (Aß) plaques. Systemic inflammation and obesity may exacerbate AD pathogenesis. We previously reported anti-inflammatory and anti-obesity effects of EPA in mice. OBJECTIVES: We aimed to determine whether EPA reduces obesity-associated metabolic dysfunctions and Aß accumulation in AD amyloidogenic mice. METHODS: Two-mo-old APPswe/PS1dE9 transgenic (TG) mice and non-TG littermates were randomly assigned to low fat (LF; 10% kcal fat), high fat (HF; 45% kcal fat), or EPA (36 g/kg)-supplemented HF diets. Body composition, glucose tolerance, and energy expenditure were measured, and serum and brain metabolic markers were tested 38 wk postintervention. Outcomes were statistically analyzed via 3-factor ANOVA, modeling genotype, sex, and diet interactions. RESULTS: HF-fed males gained more weight than females (Δ = 61 mg; P < 0.001). Compared with LF, HF increased body weights of wild-type (WT) males (Δ = 31 mg; P < 0.001). EPA reduced HF-induced weight gain in WT males (Δ = 24 mg; P = 0.054) but not in females. HF mice showed decreased glucose clearance and respiratory energy compared with LF-fed groups (Δ = -1.31 g/dL; P < 0.001), with no significant effects of EPA. However, EPA conferred metabolic improvements by decreasing serum leptin and insulin (Δ = -2.51 g/mL and Δ = -0.694 ng/mL, respectively compared with HF, P ≤ 0.05) and increasing adiponectin (Δ = 21.6 ng/mL; P < 0.001). As we expected, TG mice expressed higher serum and brain Aß than WT mice (Δ = 0.131 ng/mL; P < 0.001 and Δ = 0.56%; P < 0.01, respectively), and EPA reduced serum Aß1-40 in TG males compared with HF (Δ = 0.053 ng/mL; P ≤ 0.05). CONCLUSIONS: To our knowledge, this is the first report that EPA reduces serum Aß1-40 in obese AD male mice, warranting further investigations into tissue-specific mechanisms of EPA in AD.
Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Masculino , Animais , Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/metabolismo , Ácido Eicosapentaenoico/farmacologia , Doenças Neurodegenerativas/complicações , Obesidade/metabolismo , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Glucose , Modelos Animais de Doenças , Camundongos Endogâmicos C57BLRESUMO
White adipose tissue (WAT) and brown adipose tissue (BAT) are involved in whole-body energy homeostasis and metabolic regulation. Changes to mass and function of these tissues impact glucose homeostasis and whole-body energy balance during development of obesity, weight loss, and subsequent weight regain. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), which have known hypotriglyceridemic and cardioprotective effects, can also impact WAT and BAT function. In rodent models, these fatty acids alleviate obesity-associated WAT inflammation, improve energy metabolism, and increase thermogenic markers in BAT. Emerging evidence suggests that ω-3 PUFAs can also modulate gut microbiota impacting WAT function and adiposity. This review discusses molecular mechanisms, implications of these findings, translation to humans, and future work, especially with reference to the potential of these fatty acids in weight loss maintenance.
Assuntos
Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/fisiologia , Ácidos Graxos Ômega-3/farmacologia , Inflamação/metabolismo , Animais , Ácidos Graxos Ômega-3/administração & dosagem , HumanosRESUMO
BACKGROUND/OBJECTIVES: Mechanisms of obesity-associated insulin resistance and dysglycemia in South Asians remain relatively unknown. The objective of this study was to detect subcutaneous (SAT) vs. visceral (VAT) adipose tissue characteristics and adipocytokines associated with obesity, insulin resistance, and dysglycemia in South Asian women. SUBJECTS/METHODS: This was a hospital-based cross-sectional study conducted in Sri Lanka. Subjects comprised of 58 adult women who underwent routine abdominal surgeries. SAT and VAT were obtained from anterior abdominal wall and omentum, respectively. Measures of adiposity, serum insulin and glucose, SAT and VAT crown-like structures (CLS), macrophages, resistin by immunohistochemistry, mean adipocyte area (MAA), and serum adipocytokines were examined. RESULTS: The homeostatic model assessment for insulin resistance (HOMA-IR) score significantly correlated with age and waist circumference (WC), but not with body mass index (BMI). Although the number of CLS positively correlated with BMI, there were no significant differences between the number of CLS in women with normal fasting glucose (NFG) vs. those with impaired fasting glucose (IFG), indicating that adipose tissue macrophage infiltration is unlikely to be related to dysglycemia. In contrast, serum resistin level was on average 60% higher in women with IFG compared to ones with NFG (p < 0.05). Serum resistin levels correlated with age (r = 0.36, p < 0.05) and WC (r = 0.27, p < 0.05). There were no associations in serum levels of other adipocytokines with IFG. Adipose immunohistochemistry showed that women with IFG had a higher percentage of resistin positive adipocytes in SAT compared to ones with NFG. MAA of VAT, but not SAT, correlated with both BMI and WC. CONCLUSIONS: Resistin may be an important adipokine linking central adiposity and insulin resistance in South Asian women. Both systemic and adipose tissue resistin are linked to dysglycemia in these individuals and may be a potential biomarker for diabetes in this population.
Assuntos
Tecido Adiposo/metabolismo , Adiposidade/fisiologia , Hiperglicemia/metabolismo , Resistência à Insulina/fisiologia , Sobrepeso/metabolismo , Resistina/metabolismo , Adolescente , Adulto , Idoso , Glicemia/metabolismo , Índice de Massa Corporal , Estudos Transversais , Feminino , Teste de Tolerância a Glucose , Humanos , Hiperglicemia/sangue , Pessoa de Meia-Idade , Sobrepeso/sangue , Resistina/sangue , Sri Lanka , Circunferência da Cintura , Adulto JovemRESUMO
Strategies to reduce obesity have become public health priorities as the prevalence of obesity has risen in the United States and around the world. While the anti-inflammatory and hypotriglyceridemic properties of long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) are well known, their antiobesity effects and efficacy against metabolic syndrome, especially in humans, are still under debate. In animal models, evidence consistently suggests a role for n-3 PUFAs in reducing fat mass, particularly in the retroperitoneal and epididymal regions. In humans, however, published research suggests that though n-3 PUFAs may not aid weight loss, they may attenuate further weight gain and could be useful in the diet or as a supplement to help maintain weight loss. Proposed mechanisms by which n-3 PUFAs may work to improve body composition and counteract obesity-related metabolic changes include modulating lipid metabolism; regulating adipokines, such as adiponectin and leptin; alleviating adipose tissue inflammation; promoting adipogenesis and altering epigenetic mechanisms.
Assuntos
Ácidos Graxos Ômega-3/farmacologia , Síndrome Metabólica/dietoterapia , Obesidade/dietoterapia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Fármacos Antiobesidade/farmacologia , Composição Corporal/efeitos dos fármacos , Exercício Físico , Humanos , Resistência à Insulina , Síndrome Metabólica/prevenção & controle , Obesidade/prevenção & controle , Paniculite/dietoterapia , Paniculite/metabolismo , Paniculite/prevenção & controle , Verduras/químicaRESUMO
As the incidence of noncommunicable diseases such as diabetes continues to rise at an alarming rate in South-East Asia, it is imperative that urgent and population-wide strategies are adopted. The most important contributors to the rise in noncommunicable disease are a rise in mean caloric intake and a decrease in physical activity. The evidence for population-based dietary approaches to counter these factors is reviewed. Several structural and cohesive interdepartmental coordination efforts are required for effective implementation of prevention strategies. Since low- and middle-income countries may lack the frameworks for effective and integrated multi-stakeholder intervention, implementation of population-based dietary and physical-activity approaches may be delayed and may be too late for effective prevention in current at-risk cohorts. Evidence-based strategies to decrease energy intake and increase physical activity are now well established and their urgent adoption by Member States of the World Health Organization South-East Asia Region is essential. In the context of Sri Lanka, for example, it is recommended that the most effective and easy-to-implement interventions would be media campaigns, restrictions on advertisement of unhealthy foods, taxation of unhealthy foods, subsidies for production of healthy foods, and laws on nutrition labelling that introduce colour coding of packaged foods.
Assuntos
Dieta , Promoção da Saúde/métodos , Doenças não Transmissíveis/prevenção & controle , Publicidade/legislação & jurisprudência , Doenças Cardiovasculares/prevenção & controle , Exercício Físico , Rotulagem de Alimentos/legislação & jurisprudência , Humanos , Obesidade/prevenção & controle , ImpostosRESUMO
BACKGROUND CONTEXT: Magnetic stimulation (MS), which is used to evaluate motor pathways, is helpful in evaluating cervical spinal cord compression (cervical myelopathy [CM]). Previous studies have shown that the central motor conduction time (CMCT), which is the time taken for the nerve impulses to reach the cervical spinal roots after the stimulation of the motor cortex, is prolonged in CM. However, the duration of motor-evoked potentials (MEPs) in CM has not been studied in detail. PURPOSE: To compare the duration, CMCT and amplitude of MEPs by MS between patients with clinical and magnetic resonance imaging (MRI) features of CM and a control group. STUDY DESIGN/SETTING: A cross-sectional study done at Teaching Hospital, Peradeniya, Sri Lanka. PATIENT SAMPLE: Consecutive patients with clinical features of cervical spondylotic myelopathy, without coexisting neurological abnormality. METHODS: Transcranial and cervical spinal magnetic stimulation were performed on 21 patients with clinical and MRI features of spondylotic CM (mean age, 43.5years; range, 36-63 years; 9 men) and 17 healthy volunteers (mean age, 39.05 years; range, 23-54yrs; 6 males) using a circular coil with a Magstim 200 stimulator. MEPs were recorded over abductor digiti minimi muscle on both hands. RESULTS: Seventeen patients had upper motor neuron (UMN) features in all four limbs; in the others, both lower limbs and one upper limb were affected. The upper limbs with UMN features had shorter duration MEPs compared with the control group. The CMCT and the total motor conduction time were also delayed in the CM group. All three differences were very highly significant (t=5.75, -3.76, 5.27; p<.001). The amplitudes showed no significant difference between the two groups (t=1.27, p=.208). CONCLUSION: This study shows that in addition to the CMCT, the duration of MEPs is also useful in evaluating patients with CM using MS.