Reduction In Lean Mass Research Articles

Male and female cats have different regional body compositions and energy requirements for weight loss and weight maintenance.

Body composition and energy requirements are different between males and females in several species, and both interfere with weight loss. The aim of this study was to compare the total and regional body composition and energy requirements in obese male (n=8) and female (n=8) cats, during weight loss and weight maintenance over 17 subsequent weeks after regimen. The total and regional (thoracic and pelvic limbs, and trunk) body composition was assessed by dual-energy X-ray absorptiometry (DXA). Females exhibited a higher fat mass (FM) than males (p<0.05), and the trunk was the site with greater fat accumulation regardless of gender. A 23.0±2.8% reduction in body weight was followed by a 50.3±9.4% and a 37.0±8.9% reduction in fat in the trunk region in males and females respectively. Lean mass (LM) mobilization was also increased in the trunk (p<0.05), and the loss of LM was associated with a reduction in bone mass. The energy intake to achieve the same rate of weight loss was 12.9±3.4% higher in males (p<0.05). The cats exhibited a gradual increase in energy requirements to maintain their body weight after weight loss (p<0.05). It was concluded that obese cats mainly accumulate fat in the trunk. The reduction in lean mass after the regimen also occurred in the trunk, with no modifications in the skeletal muscle mass of the limbs. Neutered male cats have higher energy requirements than neutered females, and gender should be considered during obesity management in cats.

EIF3f depletion impedes mouse embryonic development, reduces adult skeletal muscle mass and amplifies muscle loss during disuse.

In muscular cells, eukaryotic initiation factor subunit f (eIF3f) activates protein synthesis by allowing physical interaction between mechanistic target of rapamycin complex 1 (MTORC1) and ribosomal protein S6 kinase 1 (S6K1), although its physiological role in animals is unknown. A knockout approach suggests that homozygous mice carrying a null mutation of the eIF3f gene fail to develop and consequently die at early embryonic stage, whereas heterozygous mice associated with a partial depletion of eIF3f gene grow normally and are phenotypically indistinguishable from wild-type mice. Heterozygous mice express reduced eIF3f mRNA and protein levels in skeletal muscles and show diminished muscle mass associated with a decrease in the protein synthesis rate and an inhibition of the MTORC1 pathway. During hindlimb immobilization, heterozygous eIF3f mice display an exacerbated immobilization-induced muscle atrophy associated with reduced protein synthesis. These results highlight the essential role of eIF3f during embryonic development and its involvement in muscular homeostasis via protein synthesis regulation. Eukaryotic translation initiation factor 3, subunit F (eIF3f), a component of eIF3 complex, plays an important role in protein synthesis regulation, although its physiological functions are unknown. We generated and analysed mice carrying a null mutation in the eIF3f gene. We showed that homozygous eIF3f knockout fail to develop and that eIF3f-/- embryos die at an early stage of development but after the pre-implantation stage. However, disrupting one eIF3f allele does not affect growth, viability and fertility of heterozygous mice but, instead, reduces eIF3f mRNA and protein levels in all tissues examined. Although heterozygous mice are phenotypically indistinguishable from wild-type mice, they present a diminished body weight and a lean mass reduction associated with normal body size. Interestingly, skeletal muscles are mainly affected and display an altered cell size without modification of fibre number. Skeletal muscles of heterozygous mice show a deficiency in polysome content, a decrease in protein synthesis rate and an inhibition of the mechanistic target of rapamycin (MTOR) pathway. We then studied the effects of hindlimb immobilization that mimic muscle disuse on heterozygous mice aiming to further explore the involvement of eIF3f in protein synthesis. We found that eIF3f partial depletion amplifies muscle atrophy compared to wild-type mice. Mass and cross-sectional area decreases were associated with reduced MTOR pathway activation and protein synthesis rate. Taken together, our data indicate that eIF3f is essential for mice embryonic development and controls adult skeletal muscle mass via protein synthesis regulation in a MTOR-dependent manner.

Iron Deficiency and Neuroendocrine Regulators of Basal Metabolism, Body Composition and Energy Expenditure in Rats.

Although dietary iron is a determinant of iron status in animals, body fat mass has been reported to have an inverse association with iron status in human studies. The goal of this study was to determine the relationship between Fe homeostasis, body composition, energy expenditure and neuroendocrine regulators for severe Fe-deficiency anaemia. Forty male Wistar albino rats recently weaned were divided at random into two groups: the control group was fed the basal diet, AIN-93G diet (normal-Fe) and the anaemic group received a low-Fe diet for 40 days. Neuroendocrine parameters that regulate basal metabolism and appetite (thyroid hormones, ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon, insulin, adrenocorticotropic hormone and corticosterone), body composition, respiratory volumes, energy expenditure, haematological and biochemical were assessed. Total body fat was lower, whereas lean mass, free and total water were higher in the anemic group. O2 consumption, CO2 production, energy expenditure (EE) and respiratory quotient (RQ) were lower in the Fe-deficient animals. Triiodothyronine and thyroxine hormones decreased, while thyroid-stimulating hormone increased in the anemic group. Circulating levels of ghrelin were lower in the anemic group, while GIP, glucagon, insulin, corticosterone and adrenocorticotropic hormone levels were higher. Fe-deficiency impairs weight gain in the rats, with marked reductions in lean mass and body fat, indicating lower energy stores.

The Obesity Paradox in Cardiovascular Diseases

The Obesity Paradox in Cardiovascular Diseases

Effects of high altitude mountaineering on body composition: a systematic review

High altitude mountaineering is characterized by high energetic requirements due to the environment in which the activity is developed: negative energy balance, extreme cold, high altitude and the assumption of potential risks can be found during the practice of this sport. High altitude mountaineering, as a result of the previous factors, induces changes in body composition which have never been studied previously in a systematic review. A search within four different databases (PubMed, SportDiscus, Scopus and Medline) was performed using the thesaurus terms "Mountaineering" and "Body composition". A second search was performed using the following terms "Altitude" and "Body composition". The selection criteria included studies with healthy adults which evaluated the effects of at least 14 days of uninterrupted stays at altitudes above 4,000 m. The studies included in the review assessed body composition through different methods such as anthropometry, bioimpedance, dual energy x-ray absorptiometry, hydrostatic weighing and air displacement plethysmography. The search was performed up to and including December 1st 2018. Eleven observational studies met the inclusion criteria. All studies reported weight loss, of which five reported significant reductions in lean mass and six reported reductions in fat mass. Also, three studies reported reductions in both fat mass and lean mass. Current evidence is limited to observational studies with important confounding factors affecting the final conclusions. Longitudinal studies with a better methodological design and control groups are needed in order to verify these results.

Effects of dancing compared to walking on cardiovascular risk and functional capacity of older women: A randomized controlled trial

Aging is characterized by reductions in lean mass simultaneously to increases in visceral adipose tissue, elevating cardiovascular risk (CVR) and physical dependence. Dancing has been recommended for improving fall-risk and CVR, however, comparisons with traditional exercises are limited. This study aimed to compare the effects of dancing with walking on CVR and functionality of older women. Thirty sedentary women (65 ± 5 years, BMI 27 ± 4 kg/m2) were randomized into three groups (n = 10/group): dancing, walking or stretching (active control). All interventions lasted 8 weeks (60 min sessions): dancing/walking 3×/week, stretching 1×/week. Dancing: several styles, no partner. Walking: treadmill, 60% peak oxygen consumption (VO2peak). Stretching: large muscle groups, no discomfort. Before and after interventions assessments: VO2peak (primary outcome), total cholesterol, HDL-C, LDL-C, glucose, insulin, CRP, TNF-α, waist and hip circumferences, visceral adipose tissue (VAT), muscle thickness, maximal muscle strength/power, static and dynamic balance, gait ability, flexibility, chair-raise and level of physical activity (PA). generalized estimating equations, post-hoc LSD (p < 0.05), SPSS 22.0. (Mean-CI): (before vs after): group vs time interaction showed increases in VO2peak (mL·kg-1·min-1) for dancing 23.3 (20.8-25.8) vs 25.6 (23.4-27.8), and walking 23.4 (21.3-25.5) vs 27.0 (25.4-28.6), with no differences for stretching 23.5 (21.3-25.7) vs 23.0 (21.0-24.9). Lower body muscle power and static balance also improved for dancing and walking, but not for stretching. Main time effect showed improvements in CRP, TNF-α, LDL-C, HDL-C, VAT, waist, hip, chair raise, flexibility and level of daily PA for all groups. Dancing induced similar increases in VO2peak, lower body muscle power and static balance as walking, while the stretching group remained unchanged. Pooled effects showed improvements in body composition, lipid and inflammatory profile, which are supported by increased PA levels. NCT03262714.

Sarcopenic Obesity: Definition, Health Consequences and Clinical Management

Over the last decade, a new condition, which occurs in the presence of both sarcopenia and obesity, has been termed “sarcopenic obesity”. The term describes the coexistence of obesity, defined as the increase in body fat mass deposition, and sarcopenia, defined as the reduction in lean mass and muscle strength. However, many uncertainties still surround the condition of sarcopenic obesity in terms of its definition, the adverse short- and long-term health effects (i.e., medical disease, psychosocial functioning, quality of life and mortality) and its clinical management. The aim of this short communication is to emphasize some crucial aspects that future research should take into account in order to avoid bias and misinterpretations and to underline that the study of sarcopenic obesity should be considered a scientific and clinical priority, as reported by the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Association for the Study of Obesity (EASO).

Gut microbiota mediates the anti-obesity effect of calorie restriction in mice

Calorie restriction (CR) extends lifespan and elicits numerous effects beneficial to health and metabolism in various model organisms, but the underlying mechanisms are not completely understood. Gut microbiota has been reported to be associated with the beneficial effects of CR; however, it is unknown whether these effects of CR are causally mediated by gut microbiota. In this study, we employed an antibiotic-induced microbiota-depleted mouse model to investigate the functional role of gut microbiota in CR. Depletion of gut microbiota rendered mice resistant to CR-induced loss of body weight, accompanied by the increase in fat mass, the reduction in lean mass and the decline in metabolic rate. Depletion of gut microbiota led to increases in fasting blood glucose and cholesterol levels independent of CR. A few metabolism-modulating hormones including leptin and insulin were altered by CR and/or gut microbiota depletion. In addition, CR altered the composition of gut microbiota with significant increases in major probiotic genera such as Lactobacillus and Bifidobacterium, together with the decrease of Helicobacter. In addition, we performed fecal microbiota transplantation in mice fed with high-fat diet. Mice with transferred microbiota from calorie-restricted mice resisted high fat diet-induced obesity and exhibited metabolic improvement such as alleviated hepatic lipid accumulation. Collectively, these data indicate that CR-induced metabolic improvement especially in body weight reduction is mediated by intestinal microbiota to a certain extent.

Impacto de la obesidad en la salud de la mujer adulta mayor

La población mundial ha envejecido y se está haciendo más femenina. La mujer adulta mayor sufre el impacto negativo del envejecimiento y la falla ovárica, con niveles bajos de estrógenos por la menopausia. Incrementa hasta en 33% de ellas el peso corporal, en rango de sobrepeso u obesidad, con redistribución de la grasa en la región visceral y disminución de la masa magra. Ello la predispone a todas las comorbilidades asociadas con la obesidad así como las enfermedades metabólicas y cardiovasculares, además de mortalidad a edad más temprana que sus pares que cursan con peso normal. Se ha incrementado la esperanza de vida. Por tanto sería ideal añadir a estos años calidad, viviendo libre de enfermedades crónicas e invalidantes y hasta donde sea posible lograr que ellas sean autosuficientes e independientes. Hay que intervenir para buscar la pérdida de peso intencional en aquellas que lo tienen incrementado y así reducir la morbimortalidad que se aumenta con la obesidad.

Association between sleep duration, fat mass, lean mass and obesity in Korean adults: the fourth and fifth Korea National Health and Nutrition Examination Surveys.

This study investigated the association between sleep duration, fat mass, lean mass and obesity. Participants of this cross-sectional study were 16905 adults included into the 4th and 5th Korea National Health and Nutrition Examination Surveys. Sleep duration was assessed by self-reported survey and categorized into ≤5, 6, 7, 8 and ≥9h per day. The group reporting 7h of sleep per day (comprised of those sleeping 7-8h per day) was used as the reference group. Body composition was measured by dual X-ray absorptiometry (DEXA). Obesity was defined based on the criteria from the Korean Society for the Study of Obesity. Least-squares means of fat mass index (FMI) and lean mass index (LMI) adjusted for age, employment status, comorbidities and physical activity were used to assess the relation between sleep duration and body composition. Multivariable logistic regression was used to calculate the adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) of obesity according to sleep duration after adjusting for sociodemographic and health-related factors. After adjustment, FMI increased with fewer hours of sleep (P for trend: <0.001) and LMI decreased with more hours of sleep (P for trend: 0.011). Compared to the reference group, sleep-deprived individuals were 1.22 times more likely to have general obesity (aOR: 1.22; 95% CI: 1.03-1.45) and 1.32 times more likely to have abdominal obesity (aOR: 1.32; 95% CI: 1.10-1.58). Our findings suggest that sleep deprivation might be related to an increase of fat mass and obesity, while oversleeping could be linked to a reduction of lean mass.

Dehydration Causes Increased Reliance on Protein Oxidation in Mice: A Test of the Protein-for-Water Hypothesis in a Mammal.

During fasting, animals rely on a mixture of fats, carbohydrates, and proteins that are derived solely from endogenous sources. The relative contributions of these metabolic fuels chiefly depend on the duration of the fast, but other factors including previous diet, environmental temperature, and activity level can modulate the fuel mixture. It has long been held that endogenous proteins are spared from catabolism until the final stages of prolonged fasting and contribute a significant proportion of energy once the other metabolic fuels have been depleted. However, evidence is mounting that protein is catabolized supplemental to fat metabolism under some circumstances. This has been shown in migratory birds that exhibit dramatic reductions in lean mass during flights. One hypothesis to explain this seemingly maladaptive metabolic strategy is that the catabolism and oxidation of protein in situ yields five times more metabolic water than that generated through fat oxidation alone. Recent support for this hypothesis is that birds benefit from such a strategy due to their uricotelic nature. However, it remains unclear whether ureotelic mammals would also employ this strategy. Here we test the protein-for-water hypothesis in resting laboratory mice subjected to water deprivation during fasting while we tracked rates of protein and lipid catabolism using endogenously incorporated 13C-leucine and 13C-palmitic acid. We found no differences in instantaneous leucine oxidation; however, cumulative differences in instantaneous leucine oxidation ultimately resulted in a higher total leucine oxidation after 72 h of fasting in water-deprived animals. We also found that lipid oxidation was 8% higher in the hydrated mice, but the difference was not significant presumably because of a concomitant reduction in metabolic rates of the water-deprived mice. Our results indicate that mammals do increase rates of protein catabolism during dehydration but to a lesser degree than birds. The ability of mammals to produce highly concentrated urine and their lower inherent rates of protein turnover apparently preclude mammals from taking full advantage of the protein-for-water strategy during fasting under dehydrating conditions.

Effects of Weight Loss on Lean Mass, Strength, Bone, and Aerobic Capacity.

This study aimed to evaluate the hypothesis that exercise attenuates the reductions in lean mass, muscle strength, bone mineral density, and V˙O2max that accompany modest weight loss induced by calorie restriction (CR). Overweight, sedentary women and men (n = 52, 45-65 yr) were randomized to 6%-8% weight loss by using CR, endurance exercise training (EX), or both (CREX). The CR and the CREX groups underwent counseling to reduce energy intake by 20% and 10%, respectively. The EX and the CREX groups exercised 7.4 ± 0.5 and 4.4 ± 0.5 h·wk, respectively. Before and after 16.8 ± 1.1 wk of weight loss, lean mass and bone mineral density were measured with dual-energy x-ray absorptiometry, strength was measured with dynamometry, and aerobic capacity (V˙O2max) was measured with indirect calorimetry during maximal-intensity treadmill exercise. Weight loss was ~7% in all groups. Decreases in whole-body (~2%, P = 0.003) and lower extremity (~4%, P < 0.0001) lean mass occurred in the CR group (both P < 0.05). Despite similar weight loss, these reductions were attenuated in the CREX group (~1%, P = 0.44 and ~2%, P = 0.05, respectively) and absent in the EX group. Absolute aerobic capacity decreased ~6% in the CR group (P = 0.04), was unchanged in the CREX group (P = 0.28), and increased ~15% in the EX group (P < 0.0001). No changes in muscle strength or bone were observed. Modest weight loss (~7%) induced by 20% CR in overweight women and men decreases lean mass and reduces absolute V˙O2max. Exercise protects against these effects. Although the CR-induced changes might be considered physiologically appropriate for a reduced body weight, exercise preserves and/or improves these parameters during weight loss, which likely improves physical function. These findings support the notion of using exercise as an important component of weight loss programs.

Effects of testosterone treatment on body fat and lean mass in obese men on a hypocaloric diet: a randomised controlled trial.

BackgroundWhether testosterone treatment has benefits on body composition over and above caloric restriction in men is unknown. We hypothesised that testosterone treatment augments diet-induced loss of fat mass and prevents loss of muscle mass.MethodsWe conducted a randomised double-blind, parallel, placebo controlled trial at a tertiary referral centre. A total of 100 obese men (body mass index ≥ 30 kg/m2) with a total testosterone level of or below 12 nmol/L and a median age of 53 years (interquartile range 47–60) receiving 10 weeks of a very low energy diet (VLED) followed by 46 weeks of weight maintenance were randomly assigned at baseline to 56 weeks of 10-weekly intramuscular testosterone undecanoate (n = 49, cases) or matching placebo (n = 51, controls). The main outcome measures were the between-group difference in fat and lean mass by dual-energy X-ray absorptiometry, and visceral fat area (computed tomography).ResultsA total of 82 men completed the study. At study end, compared to controls, cases had greater reductions in fat mass, with a mean adjusted between-group difference (MAD) of –2.9 kg (–5.7 to –0.2; P = 0.04), and in visceral fat (MAD –2678 mm2; –5180 to –176; P = 0.04). Although both groups lost the same lean mass following VLED (cases –3.9 kg (–5.3 to –2.6); controls –4.8 kg (–6.2 to –3.5), P = 0.36), cases regained lean mass (3.3 kg (1.9 to 4.7), P < 0.001) during weight maintenance, in contrast to controls (0.8 kg (–0.7 to 2.3), P = 0.29) so that, at study end, cases had an attenuated reduction in lean mass compared to controls (MAD 3.4 kg (1.3 to 5.5), P = 0.002).ConclusionsWhile dieting men receiving placebo lost both fat and lean mass, the weight loss with testosterone treatment was almost exclusively due to loss of body fat.Trial registrationclinicaltrials.gov, identifier NCT01616732, registration date: June 8, 2012Electronic supplementary materialThe online version of this article (doi:10.1186/s12916-016-0700-9) contains supplementary material, which is available to authorized users.

Rictor/mTORC2 loss in osteoblasts impairs bone mass and strength

Mammalian target of rapamycin (mTOR) is a Ser/Thr kinase conserved through evolution that coordinates extra cellular signals associated with cell growth. Main functions of mTOR present in the form of two complexes, namely mTORC1 and mTORC2, which are distinct in their unique components, raptor and rictor. In the current study, using a Cre/loxp system, we found an anabolic effect of mTORC2 signaling on skeleton. Osteoblast differentiation was reduced, with down-regulation of mTORC2 signaling activity in primary cultures of osteoblasts that did not contain rictor. Mice with a specific deletion of rictor in mature osteoblasts showed a significant reduction in lean mass and bone mineral density by dual energy x-ray absorptiometry analysis. Micro-computed tomography, histomorphometric, and molecular biological analyses revealed a marked impairment of the cortical bone mass and microarchitecture, as well as minor changes in trabecular bone, of the Rictorob-/- mice. Cortical bone mass and thickness of the femoral mid-shaft were dramatically reduced, with unusual increases in porosity and marrow area in Rictorob-/- mice. Thinner trabeculae were found in the L4 vertebrae with relatively normal structural indices of trabecular numbers and separation. A lower rate of bone turnover was observed, as the consequence of the decreased individual osteoblast activity and bone resorption. Furthermore, these changes were associated with significantly decreased bone biomechanical properties. In conclusion, expression of rictor in osteoblasts is essential for the maintenance of normal bone remodeling and microarchitecture, especially for the maintenance of the cortical bone.

Mobilization of mercury from lean tissues during simulated migratory fasting in a model songbird.

The pollutant methylmercury accumulates within lean tissues of birds and other animals. Migrating birds catabolize substantial amounts of lean tissue during flight which may mobilize methylmercury and increase circulating levels of this neurotoxin. As a model for a migrating songbird, we fasted zebra finches (Taeniopygia guttata) that had been dosed with 0.0, 0.1, and 0.6 parts per million (ppm) dietary methylmercury and measured changes in blood total mercury concentrations (THg) in relation to reductions in lean mass. Birds lost 6–16% of their lean mass during the fast, and THg increased an average of 12% and 11% in the 0.1 and 0.6 ppm treatments, respectively. Trace amounts of THg in the 0.0 ppm control group also increased as a result of fasting, but remained extremely low. THg increased 0.4 ppm for each gram of lean mass catabolized in the higher dose birds. Our findings indicate that methylmercury is mobilized from lean tissues during protein catabolism and results in acute increases in circulating concentrations. This is a previously undocumented potential threat to wild migratory birds, which may experience greater surges in circulating methylmercury than demonstrated here as a result of their greater reductions in lean mass.

Association between sarcopenia and quality of life in quilombola elderly in Brazil.

IntroductionCurrently, there is no single consensual definition of sarcopenia in the literature. This creates a challenge for the evaluation of its prevalence and its direct or indirect impact on the quality of life of elderly populations of different races and ethnicities. Furthermore, no studies as yet have analyzed these variables in populations of elderly subjects of the “quilombola” ethnic group.ObjectiveWe aimed to verify the association between sarcopenia and quality of life in quilombola elderly using the Baumgartner and the European Working Group on Sarcopenia in Older People (EWGSOP) criteria.MethodsThis was a cross-sectional study of 70 male and female participants (mean age: 65.58±6.67 years). Quality of life was evaluated using the multidimensional 36-item Short-Form Health Survey (SF-36) of the Medical Outcomes Study. Sarcopenia was diagnosed according to the Baumgartner cutoff for appendicular skeletal muscle mass and the criteria recommended by the EWGSOP. Muscle mass and fat mass percentages were analyzed by dual-energy X-ray absorptiometry, while handgrip strength (HGS) was evaluated using a hand-held dynamometer. Physical performance was assessed through a gait speed test.ResultsThe prevalence of sarcopenia was 15% according to the Baumgartner cutoff and 10% according to EWGSOP criteria. Quilombola elderly classified as physically active or very active were at least six times less likely to develop sarcopenia than those classified as irregularly active or sedentary. HGS was negatively associated with a diagnosis of sarcopenia according to both sets of criteria. Subjects with sarcopenia reported lower scores than those without the condition on the physical role functioning and bodily pain domains of the SF-36.ConclusionIn this sample of quilombola elderly, quality of life was negatively associated with sarcopenia, regardless of the classification criteria used. Additionally, the results showed that diagnostic criteria for sarcopenia should include reductions in lean mass in addition to measures of functioning and physical performance because some subjects showed the former symptom without any alteration of the latter two variables. The cutoff value suggested by Baumgartner criteria were less accurate than that specified by the EWGSOP criteria because they do not consider functioning and physical performance. However, Baumgartner criteria were more sensitive in detecting sarcopenia because reductions in lean mass predict alterations in strength and walking speed.

Chronic Caloric Restriction Alters Nutrient Sensing in Skeletal Muscle in High‐Fat Diet Fed Rats

Caloric restriction (CR) is regarded as one of the most effective strategies for weight loss, decreasing chronic disease risk markers. However, the reduction on body weight induces both lean and fat mass loss, and the molecular mechanism underlying excessive loss of skeletal muscle mass remains largely unknown. We hypothesize that CR alters nutrient sensing pathways in muscle, causing phenotypical loss of muscle mass. To that end, the aim of our study was to analyze the changes in body composition after prolonged CR and the effect on nutrient sensing pathways. In our study, 5 to 6 week old male Sprague‐Dawley rats were fed a high fat diet (45% Kcal from fat) Ad libitum for 3 months. Rats were then divided into HF group Ad libitum (HF), maintenance group fed a control diet (ML, 100% energy requirement at baseline adjusted with body weight), and the caloric restriction group (CR, 25% energy reduction of baseline requirement with age adjustment). Food intake, body weight, and body composition were regularly monitored and recorded. Six months after the dietary intervention rats were sacrificed, nutrient sensing intermediates in serum were measured, and skeletal muscle samples were analyzed for gene expression. The HF group showed an increase of 30.5% in body weight, of which 83.0% is fat and 7.0% is lean mass, respectively. At the same time, ML maintained body weight gain (8.4%). A negative balance was observed in the CR group, with a marked 16.9% decrease in body weight, and a significant fat and lean mass reduction of 61.0% and 12.4%, respectively at the end of the experiment. Gene expression analysis of skeletal muscle revealed a 2.2‐fold increase in the expression of Activating Transcription Factor 4 (Atf4) in CR group compared to HF, as well as a 3.1‐fold upregulation of proteosomal degradation factor Muscle‐Specific Ring Finger Protein 1 (Murf1) and a 2.3‐fold increase in master myogenic regulator Follistatin (Fst). Nutrient sensing during the caloric restriction is further characterized by investigation of regulatory mechanisms of these pathways. Overall, chronic caloric restriction resulted in the activation of nutrient sensing and protein degradation pathways, which correlates to the reduced fat mass and concomitant lean mass loss in response to the reduced energy.

Frailty phenotype and chronic kidney disease: a review of the literature.

Frailty is a construct originally coined by gerontologists to describe cumulative declines across multiple physiological systems that occur with aging and lead individuals to a state of diminished physiological reserve and increased vulnerability to stressors. Fried et al. provided a standardized definition for frailty, and they created the concept of frailty phenotype which incorporates disturbances across interrelated domains (shrinking, weakness, poor endurance and energy, slowness, and low physical activity level) to indentify old people who are at risk of disability, falls, institutionalization, hospitalization, and premature death. Some authors consider the presence of lean mass reduction (sarcopenia) as part of the frailty phenotype. The frailty status has been documented in 7 % of elderly population and 14 % of not requiring dialysis CKD adult patients. Sarcopenia increases progressively along with loss of renal function in CKD patients and is high in dialysis population. It has been documented that prevalence of frailty in hemodialysis adult patients is around 42 % (35 % in young and 50 % in elderly), having a 2.60-fold higher risk of mortality and 1.43-fold higher number of hospitalization, independent of age, comorbidity, and disability. The Clinical Frailty Scale is the simplest and clinically useful and validated tool for doing a frailty phenotype, while the diagnosis of sarcopenia is based on muscle mass assessment by body imaging techniques, bioimpedance analysis, and muscle strength evaluated with a handheld dynamometer. Frailty treatment can be based on different strategies, such as exercise, nutritional interventions, drugs, vitamins, and antioxidant agents. Finally, palliative care is a very important alternative for very frail and sick patients. In conclusion, since the diagnosis and treatment of frailty and sarcopenia is crucial in geriatrics and all CKD patients, it would be very important to incorporate these evaluations in pre-dialysis, peritoneal dialysis, hemodialysis, and kidney transplant patients in order to detect and consequently treat the frailty phenotype in these groups.

Lower lean mass and higher percent fat mass in patients with Alzheimer's disease

In this study we analyzed body composition in relation to cognitive and functional status, in a cross-sectional sample of patients with Alzheimer's disease (AD).Seventy individuals (27 men, 78.1±6.5years; 43 women, 80.4±5.6years) with mild–moderate stages of AD (clinical dementia ratings 1 and 2) were selected from the Alzheimer Center, SS. Trinità Hospital, ASL 8 of Cagliari (Italy). Cognitive and psycho-functional status was evaluated using mini-mental state examination (MMSE), activities of daily living (ADL) scale, and geriatric depression scale (GDS). Mini-nutritional assessment (MNA) was applied. Anthropometric measurements were taken and body mass index (BMI) was calculated. Body composition was assessed by means of specific bioelectrical impedance vector analysis (BIVA), using the references for the elderly. In comparison with the reference group, patients with AD showed similar BMI and MNA, but peculiar bioelectrical characteristics: lower phase angles and longer vectors (p<0.05). According to specific BIVA, this bioelectrical pattern is indicative of a reduction of lean tissue mass and an increase of percent fat mass (FM%). A more accentuated lean mass reduction (p < 0.05) was observed in women with worse cognitive status and a FM% increase (p < 0.01) in women with worse functional status.In conclusion, patients with AD had lower lean tissue mass and higher percent fat mass than healthy elderly individuals. In women, this pattern was associated with cognitive and functional decline, as indicated by MMSE and ADL values. Specific BIVA showed to be a suitable technique in the elderly, that could enhance BMI and MNA information in the evaluation of nutritional status.

Do antispasmodics affect the body composition and basal metabolic rate in patients with cerebral palsy?

The aim is to describe differences in the basal metabolic rate, anthropometric and body composition measurements between cerebral palsy (CP) patients treated and not treated with antispasmodic agents. Children diagnosed with CP and a healthy control group were included in the study. Patients were divided into two groups: patients currently treated with antispasmodics (group 1) and patients without antispasmodic treatment (group 2). There were 34 children with CP, mean age 7.57±3.62 years. Although weight and height measurements were signifi cantly reduced in patient groups compared to the healthy control group, there was no signifi cant diff erence between group 1 and group 2. Body mass index, triceps and subscapular skinfold thickness, arm circumference, and waist/hip ratio were not statistically diff erent between group 1 and group 2. Although there was signifi cant reduction in lean mass, dry mass, body cell mass, basal metabolic rate and fat free mass index in patient groups as compared to control group, there was no signifi cant diff erence between group 1 and group 2 according to fat percentage, fat mass, total body water, body fat mass index, lean mass, dry mass, body cell mass, basal metabolic rate, fat free mass index, and basal metabolic rate/body weight. In conclusion, additional studies are needed to detect the exact eff ect of antispasmodic drugs on body composition in CP.