Decrease In Basal Metabolic Rate Research Articles

Algorithm for personalization of diet therapy in patients with atrial fibrillation and obesity based on metabolic status assessment

Aim: To develop an algorithm for personalizing the diet therapy of patients with obesity and atrial fibrillation (AF) based on the assessment of the metabolic status.Material and Methods. The study included 100 patients with grade III obesity and paroxysmal AF. All subjects had nonvalvular AF. Anthropometric parameters, actual nutrition, bioimedance analysis of body composition, basal metabolic rate (BMR) were assessed.Results. Changes in basal metabolism by gender were identified. In women – a decrease in the rate of carboydrate oxidation (CHO) (by 27 ± 12.2%, p < 0.05), an increase in fat oxidation (by 48,58 ± 14.6%, p < 0.01). In men – a decrease in BMR (by 26,23 ± 13.6%, p < 0.05), CHO (by 57,18 ± 18.1%, p < 0.01) and protein (by 28,06 ± 12.9%, p < 0.05), increased rate of fat oxidation (by 31,42 ± 10.0%, p <0.05). A hyperphagic pattern of actual nutrition has been established: excess daily energy intensity (by 16–44%), excess of daily intake of proteins (by 34–54%), fats (by 17% in women) and carbohydrates (by 57–72%, p < 0.05). An excessive amount of saturated fat, cholesterol, and added sugar was revealed in the diet. A deficiency in vitamin D intake was found (by 8–16%, p < 0.05). The maximum daily energy requirement for 95% of women is within 2250 kcal/day, for men – 2950 kcal/day.Conclusion. Metabolic status disorders serve as factors of hemodynamic overload, humoral and electrical dysfunction of the heart. Diet therapy is a powerful component in the treatment and prevention of AF. It is advisable to carry out an algorithm for individual correction of the chemical composition and energy value of diet therapy taking into account the optimal metabolic corridor of needs, enriching the diet with vitamin D, eliminating added sugar, cholesterol, sodium, phosphorus, and sources of vitamin K.

Ayurvedic Management of Hypothyroidism - A Case Report

Hypothyroidism is the significant endocrine problem found in general public. It is characterized by insufficient production of thyroid hormones, leading to abnormal levels. This condition prompts the decrease in Basal metabolic rate of the body. Ayurveda places a significant part to preclude the basic reason and to treat it. In Ayurveda, it tends to be associated with Kapha-vata dosha dushti, Rasavaha Strotasadushti, Medadushti and Agnimandya. In present study, a 22 years old female patient suffering from Sthaulya (~Weight gain), Duarbalya (~Weakness), Twak rukshata (~Dry skin), Kesh patana (hair loss), puffiness around eyes, mood swings, impaired memory, emotional depression, drowsiness, headache, Amalapitta (~Hyperacidity) and lethargy from last three years. She had been taking allopathic medicine without experiencing any satisfactory relief in her symptoms. In the present study, group of Herbo-mineral preparation was prescribed to the patient for a period of 4 months. After four months patient experienced relief, and her allopathic medicine was completely stopped. Keywords: Hypothyroidism, Agnimandya, Sthaulya

Оценка основного обмена у несовершеннолетних спортсменов

Objective. To assess the intensity of basal metabolism in adolescent elite athletes. Patients and methods. This study included 154 adolescent athletes (42 boys, 112 girls) aged 13–18 years (mean age: 15.3 ± 2.5 years). Basal metabolic rate (BMR) was measured in all participants using respiratory indirect calorimetry and the Harris–Benedict equation. Study design: single-center, cross-sectional, randomized, uncontrolled. Results. An increase in BMR was revealed in 79 (51%) participants, normal BMR – in 50 (33%) participants, and a decrease in BMR – in 25 (16%) participants. Increased BMR was statistically significantly more common in boys compared to girls (83% and 39% respectively, p = 0,01), whereas decreased BMR was more characteristic of girls compared to boys (20% and 4%, respectively, p = 0.001). Conclusion. Most adolescent athletes show an increase in BMR, which reflects an adaptation of the organism to high physical exertion. A decrease in BMR may indicate the presence of relative energy deficiency in athletes. The Harris–Benedict equation significantly underestimates the value of BMR in adolescent athletes and is not an alternative to respiratory indirect calorimetry when individual assessment of energy expenditure is necessary as part of biomedical support. Key words: children, high-performance sport, basal metabolic rate, indirect calorimetry

The Effect of Resistance Training on Physical Performance in Obese Women after Bariatric Surgery

Background: Bariatric surgery is one of the most common methods for weight loss. This study, explores the effects and differences of control and exercise on obese patients after surgery and observed the effects of a 4-week exercise program combined with standard postoperative treatment on the physical function and glycolipid metabolism of obese individuals following bariatric surgery. Materials and Methods: Eight of the seventeen obese female individuals who satisfied the inclusion criteria were placed in the group of exercise, and nine were placed in the group of control. During four weeks, the exercise group got a 60-minute exercise intervention three times per week (training every other day). The Control group did not engage in any athletic activity. Before and after the intervention, data were gathered. Software SPSS26.0 was employed. Since the data had a normal distribution, the groups individually were compared using the independent sample T test, whereas the groups before and after the group were contrasted using the paired sample T test. Use a non-normal distribution with a nonparametric Mann-Whitney U test. Findings: Weight, BMI, waist and neck circumferences, and hip circumferences in the exercise and control groups were substantially decreased (P<0.01) compared to the pre-test, as well as the waist-to-hip ratio (WHR) in the group of the exercise was statistically significantly reduced (P<0.05), while WHR in the Control group was not statistically different (P>0.05). The decrease in basal metabolic rate (BMR) was better in than in the Control group (P<0.05) in the exercise group. When compared to the pre-test, both groups' total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels considerably decreased (P< 0.01). Conclusion: Both groups had improvements in the composition of the body; however, exercise had a more significant effect on subjects' WHR and TF, as well as delaying the loss of skeletal muscle and BMR, than the Control group did on subjects' WC decline.

Role of Cardiac AMP-Activated Protein Kinase in a Non-pathological Setting: Evidence From Cardiomyocyte-Specific, Inducible AMP-Activated Protein Kinase α1α2-Knockout Mice.

AMP-activated protein kinase (AMPK) is a key regulator of energy homeostasis under conditions of energy stress. Though heart is one of the most energy requiring organs and depends on a perfect match of energy supply with high and fluctuating energy demand to maintain its contractile performance, the role of AMPK in this organ is still not entirely clear, in particular in a non-pathological setting. In this work, we characterized cardiomyocyte-specific, inducible AMPKα1 and α2 knockout mice (KO), where KO was induced at the age of 8 weeks, and assessed their phenotype under physiological conditions. In the heart of KO mice, both AMPKα isoforms were strongly reduced and thus deleted in a large part of cardiomyocytes already 2 weeks after tamoxifen administration, persisting during the entire study period. AMPK KO had no effect on heart function at baseline, but alterations were observed under increased workload induced by dobutamine stress, consistent with lower endurance exercise capacity observed in AMPK KO mice. AMPKα deletion also induced a decrease in basal metabolic rate (oxygen uptake, energy expenditure) together with a trend to lower locomotor activity of AMPK KO mice 12 months after tamoxifen administration. Loss of AMPK resulted in multiple alterations of cardiac mitochondria: reduced respiration with complex I substrates as measured in isolated mitochondria, reduced activity of complexes I and IV, and a shift in mitochondrial cristae morphology from lamellar to mixed lamellar-tubular. A strong tendency to diminished ATP and glycogen level was observed in older animals, 1 year after tamoxifen administration. Our study suggests important roles of cardiac AMPK at increased cardiac workload, potentially limiting exercise performance. This is at least partially due to impaired mitochondrial function and bioenergetics which degrades with age.

Thyroid Function in Adults With Prader-Willi Syndrome

Abstract Introduction: Prader-Willi syndrome (PWS) is a complex genetic syndrome in which hypothalamic dysfunction leads to extreme appetite (hyperphagia) and pituitary hormone deficiencies (PHD), among others. Compared with the ‘general endocrine population’, the population of adults with PWS is characterized by a high prevalence of intellectual disability (ID) and frequent use of psychotropic drugs. Due to hypotonia and the low muscle mass associated with the syndrome, adults with PWS have a low basal metabolic rate (BMR) and a high risk of developing obesity. Therefore, exercising is extremely important. However, PHD like hypothyroidism can cause fatigue and exercise intolerance. If left untreated, hypothyroidism can lead to a further decrease in BMR, an increase in Body Mass Index (BMI) and increased cardiovascular risk. As mortality in PWS is high (3% yearly) and often related to cardiovascular problems and obesity, it is of utmost importance to optimize thyroid function and other factors affecting BMR. Methods: In 122 adults with PWS (median age 29 y [IQR 21-39], median BMI 29 kg/m2 [IQR 26-36]), we measured TSH, free T4 and T3 (the active form of thyroid hormone) and searched the medical history for use of medication and any pre-existing diagnosis of hypothyroidism. Moreover, we performed an extensive literature search and summarized the current literature on hypothyroidism, T3 and T4 levels in adults with PWS. Results: Hypothyroidism was present in 17% and more prevalent in females (23%) than in males (10%), even though this was not statistically significant (P=0.06). Although within the reference range, serum T3 levels were relatively high compared to free T4 levels. T3 levels were significantly lower in patients that used psychotropic medication (n=45) than in patients that did not (median 1.7 [IQR 1.5-2.0] vs 2.1 [IQR 1.7-2.3], P=0.013). Conclusion: We found a prevalence of hypothyroidism of 17% (compared to 3% in the non-PWS population). T3 levels were relatively high, which might be explained by increased peripheral conversion of T4 to T3 by deiodinase type 2. Levels of the active thyroid hormone T3 were significantly lower in patients using psychotropic medication. Based on our findings, we recommend 1) yearly screening of thyroid hormone levels in adults with PWS to avoid negative effects of untreated hypothyroidism on BMR, BMI and cardiovascular risk and 2) extra monitoring of the active thyroid hormone T3 in patients using psychotropic drugs.

P38 Cambios en la composición corporal en pacientes sometidos a cirugía bariátrica

Introducción: el objetivo del descenso de peso en pacientes con obesidad es la pérdida de masa grasa (MG), sin embargo, también se pierde una proporción de masa magra (MM) que contribuye a la tasa metabólica. El músculo esquelético (ME) es un componente importante de la MM y el mejor predictor de la tasa metabólica basal (TMB). Los resultados de la cirugía bariátrica (CB) en los cambios de composición corporal y TMB son controvertidos. La disminución de la TBM puede predisponer a reganancia de peso post-quirúrgica. La bioimpedancia (BIA) es una técnica no invasiva, de bajo costo y rápido manejo, útil para medir la composición corporal en la práctica clínica.Objetivos: evaluar los cambios en la composición corporal mediante bioimpedancia en pacientes sometidos a CB.Materiales y métodos: estudio descriptivo, observacional, retrospectivo. Se incluyeron pacientes sometidos a CB desde enero de 2009 a enero de 2019.

HYPOTHERMIC EMERGENCY

SESSION TITLE: Medical Student/Resident Critical Care Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Hypothermia is defined as a core temperature below 95℉. The causes for hypothermia can be divided into two categories, impaired thermoregulation and increased heat loss. Increased heat loss can result from disorders that impair the skin barrier, heat stroke, cold exposure, and shock. Central failure, peripheral failure, hypothyroidism, hypoglycemia, and neuromuscular compromise are examples of causes secondary to impaired thermoregulation. In a severe state of hypothyroidism, known as myxedema coma, low thyroid hormone levels lead to a decrease in basal metabolic rate impairing thermogenesis. CASE PRESENTATION: A 65 year old male was brought to the hospital after being found unresponsive, lying outdoors for an unknown amount of time while temperatures were below freezing. Upon presentation to the ED, the patient was found to be obtunded, hypothermic to 80.6 F, bradycardic, and hypotensive. The patient's presentation was assumed to be from extended cold exposure and rewarming was initiated. He was intubated for airway protection, started on vasopressors, and admitted to the medical intensive care unit.Further work up showed an acute kidney injury, hyperkalemia, lactic acidosis, and rhabdomyolysis. His endocrine studies showed an elevated thyroid stimulating hormone (TSH) of 28.14, an undetectable triiodothyronine (T3) and thyroxine (T4), and abnormally normal cortisol. The patient was diagnosed with myxedema coma (MC) and started on an IV of liothyronine and levothyroxine as well as stress dose steroids for presumed adrenal insufficiency. Eight days after this presentation and after the initiation of thyroid hormone therapy, his mental status improved and he was successfully extubated. He was ultimately discharged to a skilled nursing facility 5 weeks later. DISCUSSION: Given several mechanisms contributing to the development of hypothermia, it is imperative to be conscious of endocrine disorders which can impair thermoregulation. MC is a medical emergency with a reported incidence of 0.22 per million per year in the Western world and a mortality rate as high as 60%. Mortality decreases to 20%–40% in treated individuals mainly as a result of clinician awareness, improvements in diagnostic testing, and advances in intensive care. If diagnostic criteria for MC is met, initiation of appropriate therapy should not be delayed as results of endocrine testing may not be readily available. CONCLUSIONS: Despite the high mortality rate associated with MC, due to prompt management in the intensive care unit with appropriate therapy of glucocorticoids and thyroxine, this patient's condition improved. We wish to emphasize the need for early detection and treatment of endocrine emergencies. In patients with severe hypothermia, initial steps for resuscitation efforts should also include early treatment of MC due to the associated mortality benefit. Reference #1: Zafren, Ken. "Out-of-Hospital Evaluation and Treatment of Accidental Hypothermia.” Emergency Medicine Clinics of North America, vol. 35, no. 2, 2017, pp. 261–279., https://doi.org/10.1016/j.emc.2017.01.003. Reference #2: Brown, Douglas J.a. "Accidental Hypothermia.” New England Journal of Medicine, vol. 367, no. 20, 2012, pp. 1930–1938., https://doi.org/10.1056/nejmra1114208. Reference #3: Wall CR. Myxedema coma: diagnosis and treatment. Am Fam Physician. 2000;62(11):2485-2490. DISCLOSURES: No relevant relationships by Michael Blaj, source=Web Response No relevant relationships by Priyanka Durai, source=Web Response No relevant relationships by Jennifer Lindsey, source=Web Response No relevant relationships by Daisy Ngwainmbi, source=Web Response No relevant relationships by Luis Rauseo Lopez, source=Web Response

The Effects of Aerobic Exercise on Thyroid Hormone Levels in Obese Boys

Aim: Although beneficial effects of physical exercises on adulthood obesity are well known, it is unclear how physical exercises affect thyroid hormone related body composition, basal metabolic rate and thermogenesis in obese children. Our objective is to examine the effects of physical exercise program on 3-5-3’triiodothyronine (T3) and 3-5-3’-5’tetraiodothyronine (T4) in obese boys. Materials and Method: Our study consisted of 10 obese boys (aged from 13 to 15) and a control group of 10 healthy boys age and gender matched. Before exercise program, 10 ml blood samples were taken from the obese and control group boys; and 10 ml blood samples were taken from the obese boys after program exercise 3 days/week for 12 weeks. The lipid profiles, creatine kinase (CK), creatine kinase-MB, T3 and T4 levels in blood samples were measured for both groups. Results: In present study, it was found that control group and obese boys after aerobic exercise had significantly higher T3 and T4 levels (1.63±0.17; 9.80±0.93 and 1.70±0.10; 10.1±0.54, respectively) and significantly lower CK levels (142.7±4.11 and 151.8±3.70, respectively) than those of obese boys before aerobic exercise (1.19±0.81; 7.37±0.47 and 165.3±2.49, respectively). Furthermore, it was found that aerobic exercise significantly decreased triglyceride and cholesterol levels in obese boys (104.0±3.77 and 193.7±2.90, respectively). Conclusion: When these findings are taken into account, it may be suggested that aerobic exercises can help with the improvement of decreased thyroid hormone levels which may be cause a weight increase together with a decrease in basal metabolic rate and thermogenesis in obese boys.

Exercise and Testosterone Countermeasures to Mitigate Metabolic Changes during Bed Rest

Background/Objectives: Exercise is a front-line countermeasure used to maintain astronaut health during long-duration spaceflight; however, reductions in metabolic health still occur. Accordingly, we evaluated serial changes in metabolic parameters in a spaceflight analog and evaluated the efficacy of exercise with or without the addition of low-dose testosterone treatment on mitigating adverse metabolic changes. Subjects/Methods: Healthy young (<55 years) men were randomly assigned to one of three groups during 70-days of strict, diet controlled, 6° head-down bed rest: Control (CON, n=9), exercise plus testosterone countermeasure (TEX, n=8), or exercise countermeasure plus placebo (PEX, n=9). Basal metabolic rate (BMR), glucose tolerance, and insulin sensitivity were measured before, during, and after bed rest. Exercise energy expenditure and excess post-exercise oxygen consumption were measured in TEX and PEX subjects during bed rest. Results: Leptin decreased during bed rest (Pre to BR+0 changed from 6.9 ± 5.1, 5.8 ± 4.2, and 4.7 ± 4.1 to 7.9 ±3.6, 6.5 ± 4.6, and 4.1 ±3.0 ug• L−1 for CON, PEX, and TEX respectively). Bed rest induced a decrease in BMR (Pre to BR57 changed from 1655 ± 212, 1629 ± 108, and 1706 ± 146 to 1476 ± 166, 1668 ± 142, and 1603 ± 132 kcal • day−1 ± 95%CI for CON, PEX, and TEX respectively). Similarly, bed rest negatively affected glucose metabolism assessed by 2hr OGTT glucose (Pre to BR66 changed from 6.29 ± 0.72, 5.13 ± 0.72, and 5.87 ± 0.73 to 6.62 ± 0.72, 5.83 ± 0.72, and 7.08 ± 0.72 mmol • L−1 ± 95%CI). Reambulation following bed rest positively affected glucose tolerance in CON (2hr OGTT glucose at BR+12: 5.3 ± 0.72, 6.42 ± 0.73, and 6.04 ± 0.73 mmol • L−1 ± 95%CI). Testosterone protected against bed rest induced insulin resistance (HOMA-IR from Pre to BR+66 changed from 1.74 ± 0.54, 1.18 ± 0.55, and 1.45 ± 0.56 to 2.24 ± 0.56, 1.47 ± 0.54, and 1.07 ± 0.54). Conclusion: This study confirmed that inactivity during 70 days of head-down bed rest adversely affects metabolic health. The daily exercise countermeasures were beneficial but not completely protective of bed rest induced decrements in metabolic health. Supplementary countermeasures such as testosterone may provide additional benefits not provided by exercise alone.

CPAP Effect on Cardiopulmonary Exercise Testing Performance in Patients with Moderate-Severe OSA and Cardiometabolic Comorbidities.

Background and Objectives: Obstructive sleep apnea (OSA) is associated with daytime somnolence, cognitive impairment and high cardiovascular morbidity and mortality. Obesity, associated cardiovascular comorbidities, accelerated erythropoiesis and muscular mitochondrial energetic dysfunctions negatively influence exercise tolerance in moderate-severe OSA patients. The cardiopulmonary exercise testing (CPET) offers an integrated assessment of the individual’s aerobic capacity and helps distinguish the main causes of exercise limitation. The purpose of this study is to evaluate the aerobic capacity of OSA patients, before and after short-term continuous positive airway pressure (CPAP). Materials and Methods: Our prospective study included 64 patients with newly diagnosed moderate-severe OSA (apnea hypopnea index (AHI) 39.96 ± 19.04 events/h) who underwent CPET before and after CPAP. Thirteen patients were unable to tolerate CPAP or were lost during follow-up. Results: 49.29% of our patients exhibited a moderate or severe decrease in functional capacity (Weber C or D). CPET performance was influenced by gender but not by apnea severity. Eight weeks of CPAP induced significant improvements in maximal exercise load (Δ = 14.23 W, p = 0.0004), maximum oxygen uptake (Δ = 203.87 mL/min, p = 0.004), anaerobic threshold (Δ = 316.4 mL/min, p = 0.001), minute ventilation (Δ = 5.1 L/min, p = 0.01) and peak oxygen pulse (Δ = 2.46, p = 0.007) as well as a decrease in basal metabolic rate (BMR) (Δ = −8.3 kCal/24 h, p = 0.04) and average Epworth score (Δ = −4.58 points, p < 0.000001). Conclusions: Patients with moderate-severe OSA have mediocre functional capacity. Apnea severity (AHI) was correlated with basal metabolic rate, resting heart rate and percent predicted maximum effort but not with anaerobic threshold or maximum oxygen uptake. Although CPET performance was similar in the two apnea severity subgroups, short-term CPAP therapy significantly improved most CPET parameters, suggesting that OSA per se has a negative influence on effort capacity.

Screening for basal metabolic rate and visceral fat among postmenopausal osteoporosis with type 2 diabetes mellitus

BackgroundIn people with type 2 diabetes mellitus, there is an increase in basal metabolic rate (BMR) which is associated with level of glycaemic control. Women with postmenopausal osteoporosis have decreased BMR. The aim of the present study is to find the BMR using Meffin-St Jeor predictive equation in women with type 2 diabetes mellitus (T2DM) who have attained menopause with osteoporosis. Materials & methods100 women who have attained menopause, who were diagnosed to have osteoporosis with type 2 diabetes mellitus were assessed for BMR using Meffin-St Jeor predictive equation. Detailed history of diabetes and menopause were obtained. Blood glucose value was measured using standard glucometers. Body composition for visceral fat (VF) was measured using bioelectrical impedance analysis. Level of physical activity of the participants was measured using global physical activity questionnaire (GPAQ). ResultsThe median BMR of the participants was 1.075 (714, 1483.25). Statistically significant correlation was found between BMR and GPAQ (rs = 0.731), BMR and VF (rs = 0.678). However BMR was not correlated with FBS (rs = 0.083) duration of diabetes (rs = −0.046). ConclusionThere is a decrease in BMR in women with T2DM with postmenopausal osteoporosis. BMR was significantly correlated with level of physical activity and visceral fat.

Seasonal and Sexual Variation in Metabolism, Thermoregulation, and Hormones in the Big Brown Bat (Eptesicus fuscus)

In response to seasonal variation in energy availability and thermal environment, physiological and endocrine mechanisms have evolved in temperate zone animals. Seasonal changes in hormone activity affect metabolism, body temperature, and reproductive activity. We examined the seasonal regulatory role of hormones on basal metabolic rate (BMR) and regulatory nonshivering thermogenesis (RNST) in 98 female and 17 male adult Eptesicus fuscus (big brown bat). We measured BMR, RNST, and plasma levels of thyroid hormone (T3), leptin, and cortisol in bats captured in maternity colonies in eastern Massachusetts from May to August (from arousal from the hibernation phase to the prehibernation phase). We hypothesized that all three hormones are seasonally primarily metabolic hormones and secondarily thermogenic hormones. In males, only BMR significantly changed seasonally. In females, all five variables significantly changed seasonally. The seasonal pattern of plasma leptin and cortisol levels correlated with the seasonal pattern of BMR, with an initial increase followed by a decrease, suggesting that leptin and cortisol are primarily metabolic hormones. The seasonal pattern of plasma T3 levels generally paralleled the basic seasonal pattern of RNST, with both increasing at the second half of the season, suggesting that T3 is primarily a thermogenic hormone. The observed decrease in plasma leptin levels may be necessary to allow for the observed seasonal decrease in BMR, with the similar cortisol pattern important for leptin regulation. While T3 is needed to maintain BMR, it may play a more critical role in the seasonal regulation of RNST than of BMR.

減量しながら筋肉量および基礎代謝量を高めることは可能か？

Most people who go to fitness clubs or sports gyms for weight control, and many co-medicals and physicians believe that an increase in muscle mass and/or basal metabolic rate (BMR) is possible through a combination of regular exercise and optimal protein intake during weight loss. This seems a myth, and the reasons are discussed in this article. First, muscle mass is quite difficult to quantify. The limitations of body composition measurement should be well understood. Second, increasing muscle mass during weight loss is difficult. This might be attained through strict implementation of a protein-rich, low-carbohydrate diet; high-intensity resistance training; and aerobic exercise for a long duration. However, such a strict regimen is not feasible for most people. Finally, a 1-kg increase in muscle mass corresponds to an increase of only 13 kcal of BMR per day. Thus, an increase in muscle mass of 1 kg is difficult to achieve, while the gained BMR is approximately equivalent to a decrease of 13.5 kcal of BMR according to a 3-kg decrease of adipose tissue. Weight loss, unless through an extremely sophisticated weight control program, contributes to a decrease in BMR. However, it is an accomplished fact that women with significantly less muscle mass and lower BMR live longer than men with more muscle mass and higher BMR, regardless of ethnicity. Maintaining activities of daily living and daily activity function might be more essential.

Nat1 Deficiency Is Associated with Mitochondrial Dysfunction and Exercise Intolerance in Mice

We recently identified human N-acetyltransferase 2 (NAT2) as an insulin resistance (IR) gene. Here, we examine the cellular mechanism linking NAT2 to IR and find that Nat1 (mouse ortholog of NAT2) is co-regulated with key mitochondrial genes. RNAi-mediated silencing of Nat1 led to mitochondrial dysfunction characterized by increased intracellular reactive oxygen species and mitochondrial fragmentation as well as decreased mitochondrial membrane potential, biogenesis, mass, cellular respiration, and ATP generation. These effects were consistent in 3T3-L1 adipocytes, C2C12 myoblasts, and in tissues from Nat1-deficient mice, including white adipose tissue, heart, and skeletal muscle. Nat1-deficient mice had changes in plasma metabolites and lipids consistent with a decreased ability to utilize fats forenergy and a decrease in basal metabolic rate and exercise capacity without altered thermogenesis. Collectively, our results suggest that Nat1 deficiency results in mitochondrial dysfunction, which may constitute a mechanistic link between this gene and IR.

Longitudinal changes in body composition and metabolic profile between exercise clinical trials in men with chronic spinal cord injury

Study design: Longitudinal design.Objectives: The study was undertaken to determine the effects of cessation of exercise interventions on body composition and metabolic profiles in men with chronic SCI.Settings: Clinical trials within a Medical Center.Methods: Eleven men with motor complete SCI were followed on average over a period of 2.5 years. Six men were involved in two different exercise interventions (functional electrical stimulation cycling versus arm cycling ergometer), 5 days/week for 16 weeks (exercise group), and five men served as a control (control group). Anthropometrics and dual energy X-ray absorptiometry (DXA) were captured to measure changes in lean mass (LM), fat mass (FM), percentage FM before, immediately after exercise, and after a period of 2.5 years. Basal metabolic rate (BMR) and lipid panel were also measured.Results: Thigh circumference increased by 8.5% following exercise (P = 0.042) and remained 6.4% greater than baseline measurements (P = 0.012). Leg LM increased by 9% following the exercise intervention (P = 0.03) and decreased by 16% in the follow-up visit (P = 0.02). Percentage trunk and total body FM increased by 4.5% (P = 0.008) and 3.5% (P = 0.019) in the follow-up visit, respectively, and whole body LM increased by 8.4% and decreased back by 5.4% following a 2.5 year-period. BMR significantly decreased by 15.5% following the exercise (P = 0.029) interventions.Conclusion: Exercise training is accompanied with positive changes in body composition as well as compensatory decrease in BMR, that regressed back following 2.5 years of exercise cessation. Participation in an exercise trial is unlikely to confound the measurements of a follow-up trial.

Resistant Starch and Energy Balance: Impact on Weight Loss and Maintenance

The obesity epidemic has prompted researchers to find effective weight-loss and maintenance tools. Weight loss and subsequent maintenance are reliant on energy balance—the net difference between energy intake and energy expenditure. Negative energy balance, lower intake than expenditure, results in weight loss whereas positive energy balance, greater intake than expenditure, results in weight gain. Resistant starch has many attributes, which could promote weight loss and/or maintenance including reduced postprandial insulinemia, increased release of gut satiety peptides, increased fat oxidation, lower fat storage in adipocytes, and preservation of lean body mass. Retention of lean body mass during weight loss or maintenance would prevent the decrease in basal metabolic rate and, therefore, the decrease in total energy expenditure, that occurs with weight loss. In addition, the fiber-like properties of resistant starch may increase the thermic effect of food, thereby increasing total energy expenditure. Due to its ability to increase fat oxidation and reduce fat storage in adipocytes, resistant starch has recently been promoted in the popular press as a “weight loss wonder food”. This review focuses on data describing the effects of resistant starch on body weight, energy intake, energy expenditure, and body composition to determine if there is sufficient evidence to warrant these claims.

TT Mutant Homozygote ofKruppel-like Factor 5Is a Key Factor for Increasing Basal Metabolic Rate and Resting Metabolic Rate in Korean Elementary School Children

We investigated the contribution of genetic variations of KLF5 to basal metabolic rate (BMR) and resting metabolic rate (RMR) and the inhibition of obesity in Korean children. A variation of KLF5 (rs3782933) was genotyped in 62 Korean children. Using multiple linear regression analysis, we developed a model to predict BMR in children. We divided them into several groups; normal versus overweight by body mass index (BMI) and low BMR versus high BMR by BMR. There were no differences in the distributions of alleles and genotypes between each group. The genetic variation of KLF5 gene showed a significant correlation with several clinical factors, such as BMR, muscle, low-density lipoprotein cholesterol, and insulin. Children with the TT had significantly higher BMR than those with CC (p = 0.030). The highest muscle was observed in the children with TT compared with CC (p = 0.032). The insulin and C-peptide values were higher in children with TT than those with CC (p= 0.029 vs. p = 0.004, respectively). In linear regression analysis, BMI and muscle mass were correlated with BMR, whereas insulin and C-peptide were not associated with BMR. In the high-BMR group, we observed that higher muscle, fat mass, and C-peptide affect the increase of BMR in children with TT (p < 0.001, p < 0.001, and p = 0.018, respectively), while Rohrer's index could explain the usual decrease in BMR (adjust r2 = 1.000, p < 0.001, respectively). We identified a novel association between TT of KLF5 rs3782933 and BMR in Korean children. We could make better use of the variation within KLF5 in a future clinical intervention study of obesity.

GLP-2 receptor in POMC neurons suppresses feeding behavior and gastric motility

Glucagon-like peptides (GLP-1/2) are cosecreted from endocrine L cells in the gut and preproglucagonergic neurons in the brain. Peripheral GLP-2 action is essential for maintaining intestinal homeostasis, improving absorption efficiency and blood flow, promoting immune defense, and producing efficacy in treatment of gastrointestinal diseases. However, it is unknown if CNS GLP-2 plays a physiological role in the control of energy homeostasis. Since GLP-1/2 are cotranslated from preproglucagongene and coproduced by prohormone convertase-1, it is challenging to knockout GLP-2 only. Instead, our laboratory has generated a Glp2r-floxed mouse line to dissect cell-specific GLP-2 receptor GLP-2R) action in the regulation of energy balance. Our objective was to determine if GLP-2R in the hypothalamus modulates feeding behavior and gastric emptying. We show that Glp2r mRNA and protein are highly expressed in the arcuate nucleus and dorsomedial nucleus of the mouse hypothalamus. Using the Cre-LoxP system, we generated mice that lack Glp2r expression in POMC neurons (KO; mainly in the hypothalamus). The KO mice showed hyperphagic behavior (such as increases in food intake and meal frequency), accelerated gastric emptying (assessed by [(13)C]octanoic acid breath test), and late-onset obesity, yet there was no decrease in basal metabolic rate. Infusion of GLP-2 (2.5 nmol into the 4th ventricle) suppressed food intake and gastric emptying, while GLP-2-mediated effects were abolished in the melanocortin receptor-4 (MC4R) KO mice. We conclude that Glp2r deletion in POMC neurons enhances feeding behavior and gastric motility, whereas icv GLP-2R activation suppresses food intake and gastric emptying through the MC4R signaling pathway. This study indicates that CNS GLP-2R plays a physiological role in the control of feeding behavior and gastric emptying and that this is mediated probably through the melanocortin system.

Limited Access to Food and Physiological Trade‐Offs in a Long‐Distance Migrant Shorebird. I. Energy Metabolism, Behavior, and Body‐Mass Regulation

Previous experiments showed reduction of basal metabolic rate (BMR) in birds facing energetic challenges. We alternately exposed two groups of red knots (Calidris canutus) to either 6 h or 22 h of food availability for periods of 22 d. Six h of access to food led to a 6%-10% loss of body mass over the first 8 d, with nearly all of the birds' daily energy expenditures supported by body nutrient stores during the first 2 d. Birds responded by increasing feeding behavior and food intake, but the response was slow. There were no gains of mass before day 15, which suggests a digestive bottleneck and a period of physiological adjustment. Food-restricted birds exhibited decreases in pectoral-muscle thickness and BMR in association with a loss of body mass. Although a decrease in BMR saves energy, savings represented only 2%-7% of the daily energy spent in excess of that acquired during the deficit period. Red knots did not downregulate mass-independent BMR. On the bases of recent independent findings and the pattern of mass gain observed when food access was switched from 6 h to 22 h, we suggest that these birds routinely maintain nutrient stores as a buffer against periods of energy shortages, thereby precluding the need for downregulation of mass-independent BMR.