Body Mass Regulation Research Articles

The interplay between hypothalamic and brainstem nuclei in homeostatic control of energy balance.

Energy balance and body weight are tightly regulated by homeostatic and hedonic systems of the brain. These systems are ultimately finely tuned by hypothalamic and extrahypothalamic neurocircuitry that modulate feeding and the appetite signalling cascade. The hypothalamus has been extensively researched and its role in homeostatic regulation of energy balance is well established. Later on, evidence indicated that extrahypothalamic signalling also has a critical role in regulation of body mass across the lifespan. One of these brain regions was the brainstem and specifically the dorsal vagal complex (DVC), which comprises of the area postrema (AP), nucleus of the solitary tract (NTS) and dorsal motor complex of the vagus (DMV). These brain stem nuclei were shown to also finely tune feeding behaviour through catecholaminergic, glutamatergic, and GABAergic signals. Moreover, these nuclei also receive afferent signals from the viscera through the gut, as well as humoral input from the bloodstream. Therefore, these brain stem nuclei are deemed as the port of entry where initial appetite-related signals are first conveyed and then modulated to the forebrain to hypothalamic and extrahypothalamic regions such as the arcuate nucleus (ARC) and parabrachial nucleus (PBN). Understanding the intricate interactions and projections between hypothalamic and brainstem nuclei is instrumental to comprehend energy balance regulation as a whole and to potentially address metabolic conditions such as diabetes and obesity. Further research in this area may lead to the development of targeted pharmacological and lifestyle intervention strategies that could lead to mitigation of metabolic disorders and/or promote a healthier body mass across the life span.

Efficiency of cognitive-behavioral group therapy for obesity in combination with dietary modifications in women

Data are accumulating on the direct influence of psychoemotional and psychosocial factors on the inexorable growth of obesity prevalence, and therefore the concept of an interdisciplinary approach is needed, including dietary, physical activity and mental state modifications.Aim. To determine the effectiveness of cognitive-behavioral group the­ra­py (CBGT) in combination with nutritional modifications for body mass (BM) management in women with obesity.Material and methods. The study involved 20 women (mean age 46,6±12,3 years) with a BMI ≥30 kg/m2, rigid to diet therapy. A medical psychologist and a nutritionist conducted CBGT sessions with the participants. Initially, BM, BM index, and eating behavior were assessed (DEBQ, Stunkard, CARDIA questionnaires). In addition, the following were used to study the mental status: Toronto Alexithymia Scale ­(TAS-20), vital exhaustion test, University of California, Los Angeles (UCLA) Loneliness Scale, Test of Self-Conscious Affect (TOSCA), Reeder Stress Inventory, and Psychological Stress Measure (PSM-25). The changes were studied 8 weeks after the start CBGT.Results. After 2 months, the BMI dynamics was -4,33 kg (p<0,001). A decrease in the severity of emotional eating behavior by an average of 0,77 (p<0,001), external eating behavior by 1,05 (p<0,001) points was noted, no significant changes in restrained eating behavior were obtained (p=0,43). According to the CARDIA test, after 2 months of CBGT, the detection rate of pathological significance of BM decreased by 50% (p<0,001); as well as episodes of loss of control over food intake (initially in 5 (25%) (p<0,001)), distress due to loss of control over food intake (initially in 6 (30%) (p<0,001). CBGT in combination with dietary intervention showed a decrease in the severity of chronic stress, which corresponded to an increase in the total score from 1,8±0,75 to 2,0±0,60 (p<0,05), a decrease in vital exhaustion from 5,6±3,89 to 4,1±2,66 (p=0,001) and loneliness from 34,9±12,61 to 29,9±7,57 (p=0,007), a decrease in guilt-proneness from 53,0±8,42 to 42,8±11,18 (p<0,001) and shame-proneness from 38,3±10,99 to 31,6±10,07 points (p=0,014).Conclusion. The mental state of a person has a significant impact on eating behavior and on the regulation of BM, which emphasizes the need for complex interventions to provide effective assistance to people with obesity.

Prolactin Mediates Long-Term, Seasonal Rheostatic Regulation of Body Mass in Female Mammals.

A series of well-described anabolic and catabolic neuropeptides are known to provide short-term, homeostatic control of energy balance. The mechanisms that govern long-term, rheostatic control of regulated changes in energy balance are less well characterized. Using the robust and repeatable seasonal changes in body mass observed in Siberian hamsters, this report examined the role of prolactin in providing long-term rheostatic control of body mass and photoinduced changes in organ mass (ie, kidney, brown adipose tissue, uterine, and spleen). Endogenous circannual interval timing was observed after 4 months in a short photoperiod, indicated by a significant increase in body mass and prolactin mRNA expression in the pituitary gland. There was an inverse relationship between body mass and the expression of somatostatin (Sst) and cocaine- and amphetamine-regulated transcript (Cart). Pharmacological inhibition of prolactin release (via bromocriptine injection), reduced body mass of animals maintained in long photoperiods to winter-short photoperiod levels and was associated with a significant increase in hypothalamic Cart expression. Administration of ovine prolactin significantly increased body mass 24 hours after a single injection and the effect persisted after 3 consecutive daily injections. The data indicate that prolactin has pleiotropic effects on homeostatic sensors of energy balance (ie, Cart) and physiological effectors (ie, kidney, BAT). We propose that prolactin release from the pituitary gland acts as an output signal of the hypothalamic rheostat controller to regulate adaptive changes in body mass.

The Role of Endocrine Disruptors Bisphenols and Phthalates in Obesity: Current Evidence, Perspectives and Controversies.

Excess body weight constitutes one of the major health challenges for societies and healthcare systems worldwide. Besides the type of diet, calorie intake and the lack of physical exercise, recent data have highlighted a possible association between endocrine-disrupting chemicals (EDCs), such as bisphenol A, phthalates and their analogs, and obesity. EDCs represent a heterogeneous group of chemicals that may influence the hormonal regulation of body mass and adipose tissue morphology. Based on the available data from mechanistic, animal and epidemiological studies including meta-analyses, the weight of evidence points towards the contribution of EDCs to the development of obesity, associated disorders and obesity-related adipose tissue dysfunction by (1) impacting adipogenesis; (2) modulating epigenetic pathways during development, enhancing susceptibility to obesity; (3) influencing neuroendocrine signals responsible for appetite and satiety; (4) promoting a proinflammatory milieu in adipose tissue and inducing a state of chronic subclinical inflammation; (5) dysregulating gut microbiome and immune homeostasis; and (6) inducing dysfunction in thermogenic adipose tissue. Critical periods of exposure to obesogenic EDCs are the prenatal, neonatal, pubertal and reproductive periods. Interestingly, EDCs even at low doses may promote epigenetic transgenerational inheritance of adult obesity in subsequent generations. The aim of this review is to summarize the available evidence on the role of obesogenic EDCs, specifically BPA and phthalate plasticizers, in the development of obesity, taking into account in vitro, animal and epidemiologic studies; discuss mechanisms linking EDCs to obesity; analyze the effects of EDCs on obesity in critical chronic periods of exposure; and present interesting perspectives, challenges and preventive measures in this research area.

High-altitude environments enhance the ability of Eothenomys miletus to regulate body mass during food limitation, with a focus on gut microorganisms and physiological markers.

Animals' digestion, energy metabolism, and immunity are significantly influenced by interactions between the gut microbiota and the intestinal environment of the host. Previous studies have shown that gut microbiota of Eothenomys miletus can respond to environmental changes, high fiber or fat foods. But how E. miletus in high-altitude adapt to their environment through gut microbiota and physiological changes during winter food shortages period was unclear. In the present study, we evaluated the altitude differences in gut microbiota and their interactions with physiology in terms of body mass regulation in order to study the adaptation of the gut microbiota and physiological indicators of the E. miletus under food restriction settings. E. miletus were collected for this study from Jingdong County (JD, low-altitude) and Xianggelila County (XGLL, high-altitude) in Yunnan Province, China, and split into three groups: control group, food-restricted feeding group for 7 days, and re-feeding group was offered a standard diet for 14 days. 16S rRNA gene sequencing and physiological methods were used to analyze the abundance and community structure of gut microbiota, as well as physiological indicators of each group in E. miletus. The results showed that while the RMR changed more during the period of food restriction, the body mass and major organ masses of E. miletus from high-altitude changed less. After food restriction, RMR in XGLL decreased by 25.25%, while that of in JD decreased by 16.54%. E. miletus from the XGLL had gut bacteria that were more abundant in Firmicutes and had fewer OTUs, and the microbiota had a closer interaction with physiological indicators. Moreover, the gut microbiota adapted to the food shortage environment by enhancing the genera of Bacterroides, Ruminococcus, Turicibacter, and Treponema to improve the utilization of nutrient resources. The interactions between microbial species and the equilibrium of energy homeostasis were further impacted by alterations in physiological indicators and microbial community structure. These variations were important for E. miletus to adapt to the fluctuations and changes of food resources in high-altitude region, which also expand our knowledge of organismal adaptations and the mechanisms behind the interactions between gut bacteria and host physiology.

Effects of high-fiber food on gut microbiology and energy metabolism in Eothenomys miletus at different altitudes.

Intestinal microorganisms assist the host in digesting complex and difficultly decomposed foods; expand the host's dietary ecological niche. In order to investigate the effect of high-fiber food on intestinal microorganisms of Eothenomys miletus at different altitudes, exploring the regional differences of intestinal microorganisms and their roles in body mass regulation, we collected E. miletus from Dali (DL) and Xianggelila (XGLL), which were divided into control group, high-fiber group fed with high-fiber diet for 7 days, and refeeding group fed with standard diet for 14 days after high-fiber diet. Using 16S rRNA gene sequencing technology combined with physiological methods, we analyzed the gut microbial diversity, abundance, community structure and related physiological indicators of each group, and explored the effects of high-fiber foods and regions on the diversity, structure of gut microorganisms and physiological indicators. The results showed that high-fiber food affected the food intake and metabolic rate of E. miletus, which also showed regional differences. The intestinal microorganisms of E. miletus obtained energy through the enrichment of fiber degrading bacteria under the condition of high-fiber food, while producing short-chain fatty acids, which participated in processes such as energy metabolism or immune regulation. Moreover, it also affected the colonization of intestinal microorganisms. High-fiber food promoted the enrichment of probiotics in the intestinal microbiota of E. miletus, but pathogenic bacteria also appeared. Therefore, the changes in the composition and diversity of gut microbiota in E. miletus provided important guarantees for their adaptation to high fiber food environments in winter.

Leptin/SFRP5 ratio as a potential predictor of postpartum weight retention. A prospective pilot study.

Excessive gestational weight gain (EGWG) and failure to lose weight within 6 months from delivery are important and identifiable predictors of the long-term obesity. The aim of the study was to verify clinical usefulness of several substances that had been proved to play a significant role in metabolism and body mass regulation, i.e., leptin, ghrelin, fatty acid binding protein 4 (FABP4), secreted frizzled-related protein 5 (SFRP5), and vaspin, in relation to certain laboratory results, body composition and hydration status of females in the early postpartum period. The main goal was to determine a potential marker, which assessed as early as 48 hours after delivery, could predict serious difficulties in achieving pre pregnancy body mass of women with EGWG six months afterwards. The same inclusion criteria applied to the study group (women with EGWG) as well as the control group (women with appropriate body mass gain in pregnancy). These included normal pre-pregnancy BMI, absence of any diseases prior, during pregnancy and after delivery, 6-month long breastfeeding. Postpartum weight retention (PPWR) depended positively on gestational weight gain as well as the leptin/ /SFRP5 ratio assessed 48 hours after delivery. Both obstetricians and midwives should pay special attention to proper nutrition of pregnant women. The assessment of biophysical and biochemical parameters in the early postpartum period, when the mothers are usually hospitalized, seems to allow to predict the risk of greater body weight retention. Future research will help to determine to what extent the circulating concentrations of leptin and SFRP5 in the early puerperium are important for prediction of maternal PPWR and obesity.

Chronic positive mass balance is the actual etiology of obesity: A living review

The fundamental cause of obesity is widely assumed to be an energy imbalance between calories consumed and calories expended (i.e., the energy balance theory). However, this century-old obesity paradigm is fallacious. According to known laws of physics, the actual etiology of obesity is chronic positive mass balance, not positive energy balance. Furthermore, the relevant physical law in body mass regulation is the Law of Conservation of Mass, not the Law of Conservation of Energy. It is important to understand that energy balance and mass balance are separate balances in the human body. Since calories simply represent the heat released on food oxidation, they have no impact on body mass. Body mass can only change as a result of net mass flow; thus, the only food property that can augment body mass is its nutrient mass, not its energy content. The recently proposed mass balance model describes the temporal evolution of body weight and body composition under a wide variety of feeding experiments, and it seems to provide a highly accurate description of the very best experimental human feeding data. By shifting to a mass balance paradigm of obesity, a deeper understanding of this condition may follow in the near future. The purpose of this living review is to present the core issues of the upcoming paradigm shift and some practical applications related to the subject.

Effects of exogenous melatonin on body mass and thermogenesis in red-backed vole (Eothenomys miletus) between Kunming and Dali regions.

Melatonin (MEL) is an indole hormone synthesized and secreted by the pineal gland at night, which is involved in the regulation of body mass and thermogenesis in small mammals. To test the effects of exogenous MEL on body mass and thermogenic ability in two different red-backed vole (Eothenomys miletus) populations from two different regions (Kunming [KM] and Dali [DL]) with different annual variation in climatic variables, such as temperature, sunshine and rainfall. we traced the changes of energy balance in E. miletus from KMand DL, which were placed at 25 ± 1°C with photoperiod of 12 L:12 D, intraperitoneal injection of MEL was performed daily for 28 days. The results showed that body mass and food intake were significantly decreased, while resting metabolic rate (RMR) and nonshivering thermogenesis (NST) were significantly increased after MEL injection; Contents of total protein, mitochondrial protein, the activities of cytochrome C oxidase (COX) and α-glycerophosphate oxidase (α-PGO) in liver and brown adipose tissue (BAT) were enhanced; the activity of thyroxin 5'-deiodinase (T4 5'-DII) and uncoupling protein 1 (UCP1) in BAT were also increased. Serum leptin, triiodothyronine (T3 ) levels and T3 /T4 ratio were significantly increased, thyroxine (T4 ) levels was significantly decreased. Moreover, body mass and food intake in E. miletus from KM were higher than those from DL, but RMR and NST were lower than those from DL. Changes of body mass, food intake and thermogenic activity of KM were higher than those of DL when exposed to injection of MEL, indicating that E. miletus in KM were more sensitive to MEL. Furthermore, MEL was involved in the regulation of body mass and thermogenesis in E. miletus between KM and DL.

Individual response in body mass and basal metabolism to the risks of predation and starvation in passerines.

Wintering energy management in small passerines has focused on the adaptive regulation of the daily acquisition of energy reserves within a starvation-predation trade-off framework. However, the possibility that the energetic cost of living, i.e. basal metabolic rate (BMR), is being modulated as part of the management energy strategy has been largely neglected. Here, we addressed this possibility by experimentally exposing captive great tits (Parus major) during winter to two consecutive treatments of increased starvation and predation risk for each individual bird. Body mass and BMR were measured prior to and after each week-long treatment. We predicted that birds should be lighter but with a higher metabolic capacity (higher BMR) as a response to increased predation risk, and that birds should increase internal reserves while reducing their cost of living (lower BMR) when exposed to increased starvation risk. Wintering great tits kept a constant body mass independently of a week-long predation or starvation treatment. However, great tits reduced the cost of living (lower BMR) when exposed to the starvation treatment, while BMR remained unaffected by the predation treatment. Energy management in wintering small birds partly relies on BMR regulation, which challenges the current theoretical framework based on body mass regulation.

Analysis of differential metabolites and metabolic pathways in adipose tissue of tree shrews (Tupaia belangeri) under gradient cooling acclimation

In order to investigate the influence of gradient cooling acclimation on body mass regulation in tree shrews (Tupaia belangeri), white adipose tissue (WAT) and brown adipose tissue (BAT) in T. belangeri between the control group and gradient cooling acclimation group on day 56 were collected, body mass, food intake, thermogenic capacity, differential metabolites, and related metabolic pathways in WAT and BAT were measured, the changes of differential metabolites were analyzed by non-targeted metabolomics method based on liquid chromatography-mass spectrometry. The results shown that gradient cooling acclimation significantly increased body mass, food intake, resting metabolic rate (RMR), non-shivering thermogenesis (NST), and masses of WAT and BAT. 23 significant differential metabolites in WAT between the gradient cooling acclimation group and the control group, of which the relative contents of 13 differential metabolites were up-regulated and 10 differential metabolites were down-regulated. 27 significant differential metabolites in BAT, of which 18 differential metabolites decreased and 9 differential metabolites increased. 15 differential metabolic pathways in WAT, 8 differential metabolic pathways in BAT, and 4 differential metabolic pathways involved in both WAT and BAT, including Purine metabolism, Pyrimidine metabolism, Glycerol phosphate metabolism, Arginine and proline metabolism, respectively. All of the above results suggested that T. belangeri could use different metabolites of adipose tissue to withstand low temperature environments and enhance their survival.

Roles of Ghrelin and Leptin in Body Mass Regulation under Food Restriction Based on the AMPK Pathway in the Red-Backed Vole, Eothenomys miletus, from Kunming and Dali Regions.

The phenotype plasticity of animals' physiological characteristics is an important survival strategy to cope with environmental changes, especially the change in climate factors. Small mammals that inhabit seasonally changing environments often face the stress of food shortage in winter. This study measured and compared the thermogenic characteristics and related physiological indicators in the adenosine-5'-monophosphate-activated protein kinase (AMPK) pathway in Eothenomys miletus between Kunming (KM, n = 18) and Dali (DL, n = 18) under food restriction and refeeding. The results showed that food restriction and the region have significant effects on body mass, the resting metabolic rate (RMR), hypothalamic neuropeptide gene expression, ghrelin levels in the stomach and serum, serum leptin level and the activity of AMPK, and malonyl CoA and carnitine palmitoyltransferase 1 (CPT-1) activity. Food restriction reduced the body mass, the gene expression of neuropeptide proopiomelanocortin (POMC), cocaine- and amphetamine-regulated transcription peptide (CART), and leptin level. However, the ghrelin concentration and AMPK activity increased. After refeeding, there was no difference in these physiological indexes between the food restriction and control groups. Moreover, the physiological indicators also showed regional differences, such as the body mass, POMC and CART gene expression, ghrelin concentration in the stomach and serum, and AMPK activity in DL changed more significantly. All these results showed that food restriction reduces energy metabolism in E. miletus. After refeeding, most of the relevant physiological indicators can return to the control level, indicating that E. miletus has strong phenotypic plasticity. Ghrelin, leptin, and the AMPK pathway play an important role in the energy metabolism of E. miletus under food restriction. Moreover, regional differences in physiological indicators under food restriction may be related to the different temperatures or food resources in different regions.

Emerging Nutrition Approaches to Support the Mind and Muscle for Healthy Aging.

This narrative review highlights recent advances and ongoing trials using nutrition approaches for healthy aging. Focus will be placed on nutrition therapies that target cognition ("the mind") and mobility ("the muscle"), both critical components to maintaining a high quality of life for older adults. For "the mind," two seemingly incongruent therapies are being investigated to improve cognition-the MIND diet (high in carbohydrates and anti-oxidant fruits and vegetables) and the ketogenic diet (low in carbohydrates, high in fats). For "the muscle," a focus on protein and energy intake has dominated the literature, yet a recent clinical trial supports the use of whole-grains as a tool to improve whole-body protein turnover-a primary regulator of lean body mass and muscle. Finally, emerging data and clinical trials on caloric restriction have solidified this strategy as the only nutritional approach to slow intrinsic factors of whole-body aging, which may positively impact both "the mind" and "the muscle."

The orphan G protein-coupled receptor, GPR139, is expressed in the hypothalamus and is involved in the regulation of body mass, blood glucose, and insulin

GPR139 is an orphan G-protein-coupled receptor that is expressed in restricted areas of the nervous system, including the hypothalamus. In this study, we hypothesized that GPR139 could be involved in the regulation of energy balance and metabolism. In the first part of the study, we confirmed that GPR139 is expressed in the hypothalamus and particularly in proopiomelanocortin and agouti-related peptide neurons of the mediobasal hypothalamus. Using a lentivirus with a short-hairpin RNA, we inhibited the expression of GPR139 bilaterally in the mediobasal hypothalamus of mice. The intervention promoted a 40% reduction in the hypothalamic expression of GPR139, which was accompanied by an increase in body mass, a reduction in fasting blood glucose levels, and an increase in insulin levels. In the hypothalamus, inhibition of GPR139 was accompanied by a reduction in the expression of orexin. As previous studies using a pharmacological antagonist of orexin showed a beneficial impact on type 2 diabetes and glucose metabolism, we propose that the inhibition of hypothalamic GPR139 could be acting indirectly through the orexin system to control systemic glucose and insulin. In conclusion, this study advances the characterization of GPR139 in the hypothalamus, demonstrating its involvement in the regulation of body mass, blood insulin, and glycemia.

Comparative research of intestinal microbiota diversity and body mass regulation in Eothenomys miletus from different areas of Hengduan mountain regions.

In order to investigate the effects of different areas on intestinal bacterial diversity and body mass regulation in Eothenomys miletus from Hengduan mountain regions, and to explore the community structure and diversity of intestinal microflora and their role in body mass regulation. E. miletus was collected from five areas including Deqin (DQ), Xianggelila (XGLL), Lijiang (LJ), Jianchuan (JC), and Dali (DL), we used 16S rRNA sequencing technology combined with physiological and morphological methods to study the intestinal microbiota diversity, abundance and community structure of the intestinal bacteria in winter, and to explore the influence of geographical factors, physiological indicators including food intake, resting metabolic rate (RMR), non-shivering thermogenesis (NST), neuropeptide Y (NPY), Agouti-Related Protein (AgRP), proopiomelanocortin (POMC), cocaine and amphetamine regulated transcription peptide (CART), and morphological indicators including body mass, body length and other nine indicators on the intestinal microflora diversity in E. miletus. The results showed that there were significant differences in metabolic indexes such as RMR, NST, NPY, AgRP, and morphological indexes such as body length, tail length and ear length among the five regions. Bacterial community in intestinal tract of E. miletus mainly includes three phyla, of which Firmicutes is the dominant phyla, followed by Bacteroidetes and Tenericutes. At the genus level, the dominant bacterial genera were S24-7(UG), Clostridiales (UG), and Lachnospiraceae (UG), etc. α diversity of intestinal microorganisms in DL and JC were significantly different from that in the other three regions. Genera of intestinal microorganisms in DL and JC were also the most. Moreover, Bacteroides, Ruminococcus, and Treponema could affect energy metabolism in E. miletus, which were closely related to the environment in which they lived. All of these results indicated that different areas in Hengduan Mountain had certain effects on the structure of intestinal microbial community in E. miletus, which were responded positively to changes in food abundance and other environmental factors. Furthermore, Firmicutes and Bacteroidetes play an important role in the body mass regulation in E. miletus.

The emerging role of leptin in obesity-associated cardiac fibrosis: evidence and mechanism.

Cardiac fibrosis is a hallmark of various cardiovascular diseases, which is quite commonly found in obesity, and may contribute to the increased incidence of heart failure arrhythmias, and sudden cardiac death in obese populations. As an endogenous regulator of adiposity metabolism, body mass, and energy balance, obesity, characterized by increased circulating levels of the adipocyte-derived hormone leptin, is a critical contributor to the pathogenesis of cardiac fibrosis. Although there are some gaps in our knowledge linking leptin and cardiac fibrosis, this review will focus on the interplay between leptin and major effectors involved in the pathogenesis underlying cardiac fibrosis at both cellular and molecular levels based on the current reports. The profibrotic effect of leptin is predominantly mediated by activated cardiac fibroblasts but may also involve cardiomyocytes, endothelial cells, and immune cells. Moreover, a series of molecular signals with a known profibrotic property is closely involved in leptin-induced fibrotic events. A more comprehensive understanding of the underlying mechanisms through which leptin contributes to the pathogenesis of cardiac fibrosis may open up a new avenue for the rapid emergence of a novel therapy for preventing or even reversing obesity-associated cardiac fibrosis.

Seasonal adjustments in body mass and basal thermogenesis in Chinese hwameis (Garrulax canorus): the roles of temperature and photoperiod.

For small birds to survive during seasonal acclimatization in temperate zones, regulation of body mass and thermogenesis is crucial. To determine the role of temperature and photoperiod in seasonal changes in body mass and thermogenesis in Chinese hwameis (Garrulax canorus), we compared body mass, basal metabolic rate (BMR), energy intake and cellular metabolic capacity of the tissue (muscle) and/or organs (liver, kidney, heart and small intestine) in seasonally acclimatized and laboratory-acclimated hwameis. A significant seasonal influence on body mass and BMR (which peaked in winter) was found, and these variations were mirrored by exposing the housed birds to cold temperatures or a short photoperiod. The level of dry matter intake, gross energy intake and digestible energy intake was higher during winter, and in housed animals that were exposed to cold temperatures. These results suggest that by increasing energy intake and thermogenesis, Chinese hwameis can overcome winter thermoregulatory challenges. When compared with warm-acclimated birds, cold-acclimated birds displayed higher mass-specific and whole-organ state 4 respiration in the muscle, liver and kidney, and higher mass-specific and whole-organ cytochrome c oxidase activity in the liver. These data demonstrate that cellular thermogenesis partly underpins basal thermoregulation in Chinese hwameis. Cold temperature and short photoperiod can be used as helpful environmental cues during seasonal acclimatization. However, the role of temperature is more significant compared with that of photoperiod in Chinese hwameis; the changes in energy metabolism and thermoregulation induced by temperature appear to be intensified by photoperiod.

A Refined Method for Studying Foraging Behaviour and Body Mass in Group-Housed European Starlings.

Simple SummarySmall birds such as European starlings respond rapidly to environmental challenges by losing or gaining weight. Laboratory studies of these birds are therefore useful for understanding how the environment affects body weight. However, practical constraints including the need to catch birds frequently for weighing has meant that birds are often housed alone in small cages for such studies. Such conditions are unnatural and are likely to cause stress. Consequently, the data obtained from these studies are unrepresentative of wild birds. Here, we describe a novel technology based on smart feeders that permits continuous recording of foraging behaviour and body masses from starlings housed in groups in large indoor aviaries that permit more natural behaviour. We show that the birds quickly learn to use the feeders and that the system delivers detailed real-time data on foraging behaviour and body mass, without the need for frequent catching. The data obtained allowed us to study how the foraging decisions that a bird makes within a single day affect its body weight that day. These improvements in the quality of the data that we are able to collect will help inform our understanding of the environmental causes of weight gain and obesity.Laboratory experiments on passerine birds have been important for testing hypotheses regarding the effects of environmental variables on the adaptive regulation of body mass. However, previous work in this area has suffered from poor ecological validity and animal welfare due to the requirement to house birds individually in small cages to facilitate behavioural measurement and frequent catching for weighing. Here, we describe the social foraging system, a novel technology that permits continuous collection of individual-level data on operant foraging behaviour and body mass from group-housed European starlings (Sturnus vulgaris). We report on the rapid acquisition of operant key pecking, followed by foraging and body mass data from two groups of six birds maintained on a fixed-ratio operant schedule under closed economy for 11 consecutive days. Birds gained 6.0 ± 1.2 g (mean ± sd) between dawn and dusk each day and lost an equal amount overnight. Individual daily mass gain trajectories were non-linear, with the rate of gain decelerating between dawn and dusk. Within-bird variation in daily foraging effort (key pecks) positively predicted within-bird variation in dusk mass. However, between-bird variation in mean foraging effort was uncorrelated with between-bird variation in mean mass, potentially indicative of individual differences in daily energy requirements. We conclude that the social foraging system delivers refined data collection and offers potential for improving our understanding of mass regulation in starlings and other species.

Polne razlike u kvalitetu života i motivaciji za treningom kod adolescenata prosečne i suvišne telesne mase

The main aim of this transversal study was to examine the relevant differences between the constructs of quality of life and exercise motivation among male and female adolescents of average and increased body mass. The sample included high school students from Valjevo (N = 337). The average age of the participants was M = 16.53 years (SD = .38). Two measuring instruments were used: The Exercise Motivations Inventory-2 (EMI-2) and The Kidscreen Questionnaire -27 (TKQ). The results of the Cronbach's alpha suggested that the questionnaires used in the research have satisfactory level of reliability and internal consistency, and are valid for assessing adolescent population in Serbia. The research has shown that there are internal and external motives for adolescents' exercise motivation, and that the male adolescents more favourably perceive the quality of life. Statistically significant gender differences were found, there was higher level of the evaluation of the TKQ construct among male adolescents than female adolescents which is the consequence of a more substantial view of physical well-being, pleasant feelings and moods, good family and social environment, as well as the ability to organize and arrange free time. It was also found that participants with average body mass prefer the perception of own physical activity and health more than their peers with increased body mass. Male adolescents do physical exercise for enjoyment, challenge, competition, strength and endurance, as well as for social reasons (factors such as belonging to a group, pressure, and acceptance), whereas female participants are more willing to exercise in order to control their body mass. The results of the Mann-Whitney U test revealed relevant gender differences: adolescents with average body mass are more likely to exercise because they enjoy the activity, while adolescents with increased body mass are more stimulated by the possibility of body mass regulation (p ≤ .01). This research discussed practical implications of the results on creating the motivation for exercise and quality of life among adolescents of both sexes with normal and increased body mass (BM).

Idiopathic Intracranial Hypertension: Current Neuroophthalmologic Points

Idiopathic intracranial hypertension (ICH) is a neuroophophthalmologic syndrome, the main ophthalmologic symptoms of which are vision loss and bilateral swelling of optic nerve disks (OD). The article provides a review covering various aspects of ICH. Epidemiology: ICH occurs mainly in women aged 20–45 years with body overweight. In this group of patients world incidence is 12–20 per 100 000 of population per year. In the total population it represents 0.5–2 cases per 100 000 of population per year. The eightfold gender predominance of women with ICH is observed. Etiology is not fully known until present time. The reliable connection between obesity in childbearing age women and menstrual cycle disorders as evidences of hormonal changes has been established. The probable mechanisms of increase of ICP are supposed: hyperproduction of and disturbances of its absorption, CSF mechanical pressure on the optic nerve sheath; restriction of venous outflow from the brain due to the pathology of venous sinuses; stimulating effect of abundant vitamin A in diet resulting in the fat tissue formation with the development of obesity; expression of the protein aquaporin, involved in the regulation of body mass and water metabolism in the subarachnoid space. Clinical manifestations. Ophthalmologic symptoms of ICH: transient visual impairment, sustained loss of visual acuity, photopsy, retrobulbar pain, diplopia. Non-ophthalmologic symptoms: headache, throbbing tinnitus, hearing loss, dizziness. Diagnostics. The valuable diagnostic data can be obtained by visual field investigation, ophthalmoscopic examination with revealing of bilateral OD-edema, OD and retinal optical coherent tomography, orbital ultrasound examination, brain MRI with venography. Treatment. Non-drug therapy: weight loss, lowcalorie diet with limited water and salt intake. Drug therapy: long-term oral use of carbonic anhydrase inhibitors (acetazolamide, topiramate). High doses of steroids (methylprednisone) are used for short-term treatment of patients with fulminant disease type before surgery. Surgery: bypass surgery, cerebral venous sinus stenting and fenestrations of the optic nerve sheath: bariatric surgery with reducing of stomach volume.