RESUMO
Poor maternal diet increases the risk of obesity and type 2 diabetes in offspring, adding to the ever-increasing prevalence of these diseases. In contrast, we find that maternal exercise improves the metabolic health of offspring, and here, we demonstrate that this occurs through a vitamin D receptor-mediated increase in placental superoxide dismutase 3 (SOD3) expression and secretion. SOD3 activates an AMPK/TET signaling axis in fetal offspring liver, resulting in DNA demethylation at the promoters of glucose metabolic genes, enhancing liver function, and improving glucose tolerance. In humans, SOD3 is upregulated in serum and placenta from physically active pregnant women. The discovery of maternal exercise-induced cross talk between placenta-derived SOD3 and offspring liver provides a central mechanism for improved offspring metabolic health. These findings may lead to novel therapeutic approaches to limit the transmission of metabolic disease to the next generation.
Assuntos
Exercício Físico , Placenta/metabolismo , Superóxido Dismutase/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Células Cultivadas , Desmetilação do DNA , Dieta Hiperlipídica , Feminino , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Gravidez , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Calcitriol/metabolismo , Transdução de Sinais , Superóxido Dismutase/genéticaRESUMO
BACKGROUND: Chronic kidney disease (CKD) is characterized by dysbiosis, elevated levels of uremic toxins, systemic inflammation, and increased markers of oxidative stress. These factors lead to an increased risk of cardiovascular disease (CVD) which is common among CKD patients. Supplementation with high amylose maize resistant starch type 2 (RS-2) can change the composition of the gut microbiota, and reduce markers of inflammation and oxidative stress in patients with end-stage renal disease. However, the impact of RS-2 supplementation has not been extensively studied in CKD patients not on dialysis. Aerobic exercise training lowers certain markers of inflammation in CKD patients. Whether combining aerobic training along with RS-2 supplementation has an additive effect on the aforementioned biomarkers in predialysis CKD patients has not been previously investigated. METHODS: The study is being conducted as a 16-week, double-blind, placebo controlled, parallel arm, randomized controlled trial. Sixty stage 3-4 CKD patients (ages of 30-75 years) are being randomized to one of four groups: RS-2 & usual care, RS-2 & aerobic exercise, placebo (cornstarch) & usual care and placebo & exercise. Patients attend four testing sessions: Two baseline (BL) sessions with follow up visits 8 (wk8) and 16 weeks (wk16) later. Fasting blood samples, resting brachial and central blood pressures, and arterial stiffness are collected at BL, wk8 and wk16. A stool sample is collected for analysis of microbial composition and peak oxygen uptake is assessed at BL and wk16. Blood samples will be assayed for p-cresyl sulphate and indoxyl sulphate, c-reactive protein, tumor necrosis factor α, interleukin 6, interleukin 10, monocyte chemoattractant protein 1, malondialdehyde, 8-isoprostanes F2a, endothelin-1 and nitrate/nitrite. Following BL, subjects are randomized to their group. Individuals randomized to conditions involving exercise will attend three supervised moderate intensity (55-65% peak oxygen uptake) aerobic training sessions (treadmills, bikes or elliptical machine) per week for 16 weeks. DISCUSSION: This study has the potential to yield information about the effect of RS-2 supplementation on key biomarkers believed to impact upon the development of CVD in patients with CKD. We are examining whether there is an additive effect of exercise training and RS-2 supplementation on these key variables. TRIAL REGISTRATION: Clinicaltrials.gov Trial registration# NCT03689569 . 9/28/2018, retrospectively registered.