Obesity and diabetes has become a major epidemic across the globe. Controlling obesity has been a challenge since this would require either increased physical activity or reduced caloric intake; both are difficult to enforce. There has been renewed interest in exploiting pathways such as uncoupling protein 1 (UCP1)-mediated uncoupling in brown adipose tissue (BAT) and white adipose tissue to increase energy expenditure to control weight gain. However, relying on UCP1-based thermogenesis alone may not be sufficient to control obesity in humans. On the other hand, skeletal muscle is the largest organ and a major contributor to basal metabolic rate and increasing energy expenditure in muscle through nonshivering thermogenic mechanisms, which can substantially affect whole body metabolism and weight gain. In this review we will describe the role of Sarcolipin-mediated uncoupling of Sarcoplasmic Reticulum Calcium ATPase (SERCA) as a potential mechanism for increased energy expenditure both during cold and diet-induced thermogenesis.
Adipose Tissue, Brown ; Adipose Tissue, White ; Basal Metabolism ; Diabetes Mellitus ; Energy Intake ; Energy Metabolism* ; Hand ; Humans ; Metabolism ; Motor Activity ; Muscle, Skeletal* ; Obesity ; Sarcoplasmic Reticulum Calcium-Transporting ATPases ; Thermogenesis* ; Weight Gain

BACKGROUND: Excessive weight and obesity (EwO) are independent factors in the development of heart failure; they lead to a state of myocardiopathy via inflammatory and hormonal mechanisms. If excessively accumulated, epicardial fat favors a proinflammatory state. Ventricular asynchrony is a marker of heart failure progression and has been poorly studied in EwO. The objective was evaluate the relation between epicardial fat, body mass index (BMI) and mechanical synchrony measured by echocardiography, in healthy individuals with EwO. METHODS: We included 55 healthy individuals between the ages of 18 and 35, 17 had a BMI < 25 kg/m2 (30.9%) and 38 had a BMI > 25 kg/m2 (EwO group) (69.09%), anthropometric measurements, transthoracic echocardiogram and synchrony evaluation were obtained. RESULTS: Left atrial volume, telediastolic and telesystolic left ventricular volumes and the baseline volume of the right ventricle were greater in the EwO group (20 mL/m2 vs. 15 mL/m2, p = 0.001; 106 mL vs. 82 mL, p = 0.0149 vs. 32 mL, p = 0.001 and 34 mm vs. 31 mm, p = 0.02, respectively). The Yu index also correlated with epicardial fat, r = 0.53, p < 0.01, whereby the greater the amount of epicardial fat, the greater the dispersion timing of ventricular activation. The systolic synchrony index also correlated with the BMI, p = 0.01. CONCLUSION: Mechanical intraventricular asynchrony is associated to EwO and the amount of epicardial fat; hence, asynchrony may be one more factor leading to heart failure in EwO individuals.
Body Mass Index ; Cardiomyopathies ; Echocardiography ; Heart Failure ; Heart Ventricles ; Obesity* ; Pilot Projects*