Depletion Of Body Fat Research Articles

Body Fat Depletion: the Yin Paradigm for Treating Type 2 Diabetes.

To highlight that body fat depletion (the Yin paradigm) with glucose-lowering treatments (the Yang paradigm) are associated with metabolic benefits for patients with type 2 diabetes mellitus (T2DM). The sodium-glucose cotransporter-2 inhibitor-mediated sodium/glucose deprivation can directly improve glycemic control and kidney outcome in patients with T2DM. The glucose deprivation might also promote systemic fatty acid β-oxidation to deplete ectopic/visceral fat and thereby contribute to the prevention of cardiovascular diseases. As with metabolic surgery, bioengineered incretin-based medications with potent anorexigenic and insulinotropic efficacy can significantly reduce blood glucose as well as body weight (especially in the ectopic/visceral fat depots). The latter effects could be a key contributor to their cardiovascular-renal protective effects. In addition to a healthy diet, the newer glucose-lowering medications, with body fat reduction effects, should be prioritized when treating patients with T2DM, especially for those with established cardiovascular/renal risks or diseases.

Accelerated abdominal lipid depletion from pesticide treatment alters honey bee pollen foraging strategy, but not onset, in worker honey bees.

Honey bee abdominal lipids decline with age, a change thought to be associated with the onset of foraging behavior. Stressors, such as pesticides, may accelerate this decline by mobilizing internal lipid to facilitate the stress response. Whether bees with stressor-induced accelerated lipid loss vary from controls in both the onset of foraging and nutritional quality of collected pollen is not fully understood. We asked whether stressors affect foraging behavior through the depletion of abdominal lipid, and whether stress-induced lipid depletion causes bees to forage earlier and for fattier pollen. We tested this by treating newly emerged bees with one of two pesticides, pyriproxyfen (a juvenile hormone analog) and spirodiclofen (a fatty acid synthesis disruptor), that may affect energy homeostasis in non-target insects. Bees fed these pesticides were returned to hives to observe the onset of foraging behavior. We also sampled foraging bees to assay both abdominal lipids and dietary lipid content of their corbicular pollen. Initially, spirodiclofen-treated bees had significantly more abdominal lipids, but these declined faster compared with controls. These bees also collected less, yet more lipid-rich, pollen. Our results suggest that bees with accelerated lipid decline rely on dietary lipid content and must collect fattier pollen to compensate. Pyriproxyfen treatment reduced the age at first forage but did not affect abdominal or collected pollen lipid levels, suggesting that accelerated fat body depletion is not a prerequisite for precocious foraging.

844-P: Jatupalathika Extract Acts via G-Protein-Coupled Receptors to Stimulate GLP-1 Secretion in STC-1 Cell Line

One of the most important molecular targets for the prevention and treatment of diabetes is glucagon-like peptide-1 (GLP-1) , a molecule secreted by enteroendocrine L cells in the intestine. It has been reported that nutrients, as well as non-nutritional dietary factors, can activate GLP-1 secretion. Jatupalathika (JPT) is a traditional herbal formulation of four dried fruits: Terminalia bellirica (Gaertn.) Roxb., Terminalia chebula Retz., Terminalia arjuna (Roxb.) Wight & Arn., and Phyllanthus emblica Linn. JPT extracts have traditionally been used for their anti-oxidant, anti-aging, body fat depletion, and weight loss properties. However, its effects on glucose metabolism and GLP-1 are not known. Thus, we evaluated the antidiabetes potential of JPT aqueous extracts by assessing its ability to induce GLP-1 secretion in a mouse intestinal cell line (STC-1) . The MTT assay was used to assess the cytotoxicity, and the LUMINEX multiplex assays were used to assess GLP-1 hormone secretion. When compared to control, JPT extracts (125 µg/ml) increased GLP-1 secretion after 45-120 minutes of incubation without any effects on cell survival. The mechanism of action of GLP-1 secretion activity in cells was studied using real-time PCR. We discovered an increase in expression of six genes related to GLP-1 secretion: SLC5A1 (encoding SGLT1) , FFAR2 (encoding GPR43) , FFAR3 (encoding GPR41) , GPR119, GPBAR1, and CABP1. This finding demonstrated that JTP extract significantly increased GLP-1 hormone production via G-protein-coupled receptor activation, which also promotes Ca2+ release from the endoplasmic reticulum. Phytochemical profiling and molecular docking study revealed that Ellagic acid and Orientin are abundant metabolites with a favorable ability to bind the FFAR2/3 protein, acting as potential agents that aid in GLP-1 production. The findings showed that JPT might be useful in the prevention and treatment of diabetes. However, more research on in vivo effects is required. Disclosure C.Chaichana: None. N.Khumkhana: None. P.Wongshaya: None. W.Deekum: None. P.Pramyothin: Research Support; Novo Nordisk, Speaker's Bureau; AstraZeneca, Boehringer Ingelheim International GmbH, Novo Nordisk.

Malnutrition Is Associated With Greater Lengths Of Stay And Rates Of Readmission Following Cardiac Transplant Or Left Ventricular Assist Device Placement

Introduction In a consensus statement, the Academy of Nutrition and Dietetics (AND) and the American Society for Parenteral and Enteral Nutrition (ASPEN) introduced the malnutrition clinical characteristics (MCC). The MCC encompasses a standardized set of characteristics that clinicians can assess to support a diagnosis of malnutrition. Studies utilizing this tool in patients undergoing orthotopic heart transplant (OHT) or placement of a left ventricular assist device (LVAD) are limited. Hypothesis Malnutrition as identified using a modified MCC is associated with greater lengths of stay and rates of readmission following OHT or LVAD placement. Methods A single-center retrospective review of 240 completed nutrition assessments using a modified MCC in patients who underwent OHT (n= 70) or LVAD placement (n=170) between January 2016 and February 2020 was performed. Four MCC characteristics were assessed: weight loss, decreased energy intake, body fat depletion and muscle mass loss. A diagnosis of malnutrition was determined for patients who met two or more of the characteristics (MCC ≥ 2, n= 153). Patients who met less than two of the characteristics did not meet criteria for diagnosis of malnutrition (MCC < 2, n = 87). Comparisons were made between groups using Mann-Whitney U and Chi-Square tests where appropriate. All tests were two-tailed and a p-value of <0.05 was considered statistically significant. Primary outcome was hospital length of stay (LOS). Secondary outcomes included total ICU LOS, post-operative ICU LOS and 30-day readmission. Results No significant difference in age, gender, ethnicity or baseline comorbidities was observed between groups. BMI was significantly lower among patients with an MCC ≥ 2 (26.5, IQR 23.4-31.9) compared to MCC < 2 (29.9, IQR 26.5-34.0, p<0.01). Primary outcome of hospital LOS was significantly greater among patients with an MCC ≥ 2 (p<0.01, table 1). Secondary outcomes of total ICU LOS, post-operative ICU LOS and 30-day readmission were significantly greater among patients with an MCC ≥ 2 compared to MCC < 2 (p<0.01, table 1). Conclusion Malnutrition as identified using a modified MCC was associated with significantly greater hospital and ICU lengths of stay and rates of 30-day readmission following OHT or LVAD placement. In a consensus statement, the Academy of Nutrition and Dietetics (AND) and the American Society for Parenteral and Enteral Nutrition (ASPEN) introduced the malnutrition clinical characteristics (MCC). The MCC encompasses a standardized set of characteristics that clinicians can assess to support a diagnosis of malnutrition. Studies utilizing this tool in patients undergoing orthotopic heart transplant (OHT) or placement of a left ventricular assist device (LVAD) are limited. Malnutrition as identified using a modified MCC is associated with greater lengths of stay and rates of readmission following OHT or LVAD placement. A single-center retrospective review of 240 completed nutrition assessments using a modified MCC in patients who underwent OHT (n= 70) or LVAD placement (n=170) between January 2016 and February 2020 was performed. Four MCC characteristics were assessed: weight loss, decreased energy intake, body fat depletion and muscle mass loss. A diagnosis of malnutrition was determined for patients who met two or more of the characteristics (MCC ≥ 2, n= 153). Patients who met less than two of the characteristics did not meet criteria for diagnosis of malnutrition (MCC < 2, n = 87). Comparisons were made between groups using Mann-Whitney U and Chi-Square tests where appropriate. All tests were two-tailed and a p-value of <0.05 was considered statistically significant. Primary outcome was hospital length of stay (LOS). Secondary outcomes included total ICU LOS, post-operative ICU LOS and 30-day readmission. No significant difference in age, gender, ethnicity or baseline comorbidities was observed between groups. BMI was significantly lower among patients with an MCC ≥ 2 (26.5, IQR 23.4-31.9) compared to MCC < 2 (29.9, IQR 26.5-34.0, p<0.01). Primary outcome of hospital LOS was significantly greater among patients with an MCC ≥ 2 (p<0.01, table 1). Secondary outcomes of total ICU LOS, post-operative ICU LOS and 30-day readmission were significantly greater among patients with an MCC ≥ 2 compared to MCC < 2 (p<0.01, table 1). Malnutrition as identified using a modified MCC was associated with significantly greater hospital and ICU lengths of stay and rates of 30-day readmission following OHT or LVAD placement.

Correlation of Physical Activity, Family Income and Consumption of Fruits and Vegetables with the Incidence of Obesity in Adolescents

Obesity is defined as an increase in energy intake compared to expenditure, resulting in depletion of body fat and eventually wearing weight. The prevalence of obesity has increased sharply in the Asia Pacific region. Many factors cause obesity. Based on data obtained from the Gorontalo District Health Office in 2018, it shows that the incidence of obesity was 8.795 cases (30.9%) consisting of 1.971 men (6.9%) and 6.824 women (24.0%). Objective: To determine several factors related to the incidence of obesity in adolescents in several high schools in Gorontalo District. This type of research uses observational analytic with a cross sectional study design. The population in this study were all students of class X and XI in SMA Negeri 1 Telaga and SMA Negeri 1 Tibawa, Gorontalo Regency as many as 1.341 students. By using the sampling technique of Proportional Stratified Random Sampling as many as 171 samples. With data analysis techniques using thetest Chi Square. The results of the study of physical activity and consumption of fruits and vegetables had no relationship with the incidence of obesity in adolescents in several high schools in Gorontalo District. Meanwhile, family income has a relationship with the incidence of obesity in adolescents in several high schools in Gorontalo Regency in 2019. It is hoped that each school can increase various activities that can reduce obesity problems and can also provide education in the form of health education to students.

Metabolic and Population Effects of Winter Tick Infestations on Moose: Unique Evolutionary Circumstances?

Moose (Alces alces) have evolved to store adequate body fat to emerge from winter in adequate nutritional condition that is key to annual productivity and neonatal survival. Blood consumption by winter ticks (Dermacentor albipictus) affects survival and productivity of moose, often resulting in marked local and regional die-offs of the calf segment of the population. Concurrent with an unprecedented frequency of winter tick epizootics (> 50% calf mortality) in the northeastern United States, productivity but not mortality of adult female moose has also declined due to low rates of twinning and calving. Chronic blood loss to winter ticks affects protein and energy balance in late winter-early spring when pregnant cows are in their energy- and protein-costly 3rd trimester, and will eventually calve and lactate initially in an environment low in digestible energy and protein. To describe this dynamic, I calculated the endogenous fat and protein balance of different-sized pregnant cows by developing energy balance equations that accounted temporally for gestation, winter tick infestation, and lactation under two consumption levels. The analysis revealed the critical importance of body mass and body fat as only large cows (25% pre-winter body fat) were immune from depletion of body fat at birth in all scenarios. Mid-sized cows (20% body fat) depleted fat reserves during gestation in most scenarios, and small cows (15% body fat) in all scenarios. The infestation and forage consumption levels influenced the predicted date of fat depletion up to several weeks, and failed calving or mortal mass loss associated with rapid loss of endogenous protein was possible in mid-sized and small cows. The continual decline in demographic parameters points to reduced body mass and body fat over time, or increased numbers of mid-sized and small cows in the population. Recent research is suggestive of a self-sustaining relationship largely influenced, ironically, by quality habitat and patterns of habitat use. This regional population is confronted with a unique and sustained combination of environmental and parasitic conditions associated with a warming climate that markedly affects its survival and reproduction in quality habitat, a unique occurrence in their evolutionary history.

A high-fat diet enriched in medium chain triglycerides triggers hepatic thermogenesis and improves metabolic health in lean and obese mice

Obesity, liver steatosis and type 2 diabetes are major diseases partly imputed to energy-dense diets rich in long chain triglycerides (LCT). The search for bioactive nutrients that help to overcome metabolic diseases is a growing field. In this regard, medium chain triglycerides (MCT) were shown to promote lipid catabolism and to stimulate brown adipose tissue thermogenesis. The objective of our study was to evaluate if the replacement of LCT by MCT in high-fat diets could prevent and/or reduce metabolic disorders. For this purpose, two cohorts of C57BL/6 mice were fed during 10 weeks with three isocaloric high-fat diets with variable MCT content. Cohort A was composed of lean mice while cohort B was composed of obese, insulin resistant mice. In cohort A, replacement of LCT by MCT preserved metabolic health, in part by triggering hepatic thermogenesis. We further found that medium chain fatty acids promote thermogenesis markers within cultured hepatocytes in a FFAR1/GPR40-dependent manner. In cohort B, high-fat diets enriched in MCT promoted body fat depletion and caused metabolic health improvement, together with the induction of thermogenesis markers in the liver as well as in subcutaneous white adipose tissue. Our study supports that replacement of LCT by MCT in high-fat diets improves the metabolic features associated with obesity.

Comprehensive Nutrition Assessment before Left Ventricular Assist Device Implantation in Chronically Ill Hospitalized Patients

Purpose Malnutrition is associated with mortality in hospitalized patients with heart failure. The Academy of Nutrition and Dietetics and the American Society for Parenteral and Enteral Nutrition recommend a standardized set of diagnostic characteristics to identify malnutrition in clinical practice. This study sought to determine the impact of comprehensive nutrition assessment on outcomes in patients undergoing left ventricular assist device implantation (LVAD), focusing on chronically ill hospitalized patients. Methods From February 2009 to August 2018, 151 patients who received a nutritional assessment prior to LVAD implantation were retrospectively reviewed. The malnutrition score (MS) was determined from 0-3 based on weight loss, decreased energy intake, body fat depletion, and muscle mass depletion prior to surgery. Serum albumin level was also assessed as a nutrition marker. Patients were categorized into 3 groups based on MS score and albumin level: a MS of 0 and albumin = 3.5 g/dL (Group 1, n = 68), a MS of 1-3 and albumin >= 3.5 g/dL (Group 2, n = 43), a MS of 1-3 and albumin Results All patients were chronically ill and deemed at risk of developing malnutrition. Median hospital stay before LVAD implant was 10 days (IQR 6 - 17). Median age of cohort was 61 years (IQR 52 - 69) and 129 (85%) were male. Ten (8.9%) were INTERMACS class 1, 63 (42%) required mechanical circulatory support prior to LVAD, and 87 (58%) were for destination therapy. Median preoperative albumin level was 3.7 g/ dL (IQR 3.3 - 3.95) and median MS was 1 (IQR 0 - 2). Overall in-hospital mortality was 10.7%. The preoperative albumin level ( = 3.5 g/ dL) did not affect the in-hospital mortality in the entire cohort (p = 0.77). Patients who had a positive MS tended to have higher mortality compared to patients with a MS of 0 (14.5% vs. 5.9%, p = 0.09). The in-hospital mortality was 5.9% in Group 1, 16.8% in Group 2, and 12.8% in Group 3 (p = 0.2). Median length of ICU stay was 8 days (IQR 6 - 11) in Group 1, 7 (IQR 5.75 - 11) in Group 2, and 7 (IQR 6 - 12) in Group 3 (p = 0.82). Conclusion Preoperative albumin level alone was not a useful marker to predict outcome in our cohort of chronically ill hospitalized patients. Routine comprehensive malnutrition assessment may help to identify high-risk cohort.

Higher fat stores contribute to persistence of little brown bat populations with white‐nose syndrome

The persistence of populations declining from novel stressors depends, in part, on their ability to respond by trait change via evolution or plasticity. White-nose syndrome (WNS) has caused rapid declines in several North America bat species by disrupting hibernation behaviour, leading to body fat depletion and starvation. However, some populations of Myotis lucifugus now persist with WNS by unknown mechanisms. We examined whether persistence of M.lucifigus with WNS could be explained by increased body fat in early winter, which would allow bats to tolerate the increased energetic costs associated with WNS. We also investigated whether bats were escaping infection or resistant to infection as an alternative mechanism explaining persistence. We measured body fat in early and late winter during initial WNS invasion and 8years later at six sites where bats are now persisting. We also measured infection prevalence and intensity in persisting populations. Infection prevalence was not significantly lower than observed in declining populations. However, at two sites, infection loads were lower than observed in declining populations. Body fat in early winter was significantly higher in four of the six persisting populations than during WNS invasion. Physiological models of energy use indicated that these higher fat stores could reduce WNS mortality by 58%-70%. These results suggest that differences in fat storage and infection dynamics have reduced the impacts of WNS in many populations. Increases in body fat provide a potential mechanism for management intervention to help conserve bat populations.

High serum free fatty acids and low leptin levels: Plausible metabolic indicators of negative energy balance in early lactating Murrah buffaloes.

Lactation is a highly demanding event in mammals, including buffaloes. It modulates the partitioning of nutrients, energy utilization, and food intake of the mother to meet her own and infant's energy needs. Failure to satisfy these energy needs leads to Negative Energy Balance (NEB). Currently, the only available indirect NEB indicator is Body Condition Score (BCS). However, direct dependency of the BCS on the peak depletion of body fat causes its inefficient use in a dairy farm. Thus, to establish objective NEB indicators in buffaloes, the serum levels of biochemical (serum β-hydroxybutyrate [BHBA] and free fatty acids [FFAs]), and endocrine (Growth Hormone [GH], insulin-like growth factor1 [IGF1], Insulin, and leptin) parameters were estimated in buffaloes. Our results revealed that serum FFA levels were significantly (p < 0.05) higher in high milk yielders (HMY) than low milk yielders (LMY) and heifers (H) during the 3rd and the 4th weeks of postpartum. The serum FFA levels were also significantly (p < 0.001) higher in the postpartum buffaloes with BCS < 3 in the field conditions. Further, serum leptin levels were significantly (p < 0.05) lower in HMY than LMY during the 3rd week of postpartum. However, the BHBA, GH, IGF1, and insulin levels were not significantly different between lactating buffaloes and H. These observations indicated that the NEB condition is probably restricted to the first month of early lactation in buffaloes. In conclusion, the simultaneous higher FFA and lower leptin levels could act as direct plausible metabolic indicators of NEB in buffaloes.

A prospective cohort study of digital cushion and corium thickness. Part 2: Does thinning of the digital cushion and corium lead to lameness and claw horn disruption lesions?

The aim of this study was to determine whether a decrease in thickness of the sole soft tissues (SST) beneath the flexor tuberosity of the distal phalanx (i.e., the digital cushion and corium) predisposed a claw to develop claw horn disruption lesions (CHDL) or a leg to lameness. Data were analyzed from a longitudinal study of 179 cows, which had been examined at 5 assessment points -8, +1, +9, +17, and +29 wk relative to their first, second, third, or fourth calving. At each assessment point, SST were measured using ultrasonography. Additional assessment point data included sole lesions and back fat thickness (BFT), and cows had been locomotion scored every 2 wk from calving. One hundred fifty-eight cows completed the study. Separate logistic regression survival analyses were constructed to assess the outcomes, either lameness on a leg or CHDL on a claw; combinations of lameness and lesions were tested as outcomes. Cow level variables tested included farm and lactation number. Variables were tested describing previous SST thickness, minimum previous SST thickness, BFT, and change in either variable between prior assessment points. Prior lesions/lameness strongly predicted repeat cases and the final models had the outcome first lesion or lameness on a claw or leg. In the reported lameness models, lameness was defined as a leg being recorded as lame twice within 3 consecutive scores, and in the reported lesion models, lesion was defined as the first presence of either a sole ulcer or a severe sole hemorrhage on a claw. Thin SST increased the likelihood of lesion occurrence; thin SST on the lateral claw predicted subsequent lameness on a leg. Thin BFT and thinning of BFT between previous assessment points increased the likelihood of future lesion occurrence. Thin SST and thinning of BFT had additional effects on the likelihood of lesion occurrence, suggesting that BFT and sole SST had independent effects on lesion occurrence. However, change in SST thickness between assessment points did not influence the likelihood of future lesions or lameness. This suggests that thin SST were not simply a result of depletion of body fat and challenges the theory that thinning of the digital cushion with body fat mobilization leads to CHDL. Other possible mechanisms by which SST become thin are discussed and could include changes in integrity of the suspensory apparatus with physiological events.

Pre‐wintering conditions and post‐winter performance in a solitary bee: does diapause impose an energetic cost on reproductive success?

1. Diapause is a dynamic process of low metabolic activity that allows insects to survive periods of harsh conditions. Notwithstanding the lowered metabolism, and because diapausing insects have no access to food, diapause has an energetic cost that may affect post‐diapause performance.2. Previous studies on the solitary bee Osmia lignaria have shown that prolonged pre‐wintering periods (the time during which individuals already in diapause remain at warm temperatures) are associated with elevated lipid consumption, fat body depletion, and body weight loss. The present study investigated whether prolonged pre‐wintering also affects reproduction, i.e. whether the costs associated with diapause could have an effect on post‐diapause performance in this species.3. Females were exposed to a range of pre‐wintering conditions, and ovary development and individual post‐wintering performance were monitored throughout their adult life span.4. No evidence of an effect of pre‐wintering duration on post‐diapause reproductive success was found. Expected differences in the timing of establishment were not observed because ovary maturation was, surprisingly, not arrested during pre‐wintering. Prolonged pre‐wintering duration did not result in decreased life span, probably because emerging females could rapidly replenish their metabolic reserves through feeding. However, there was a very strong effect of the duration of the pre‐emergence period on the likelihood of nest establishment.5. Longevity, the main factor determining fecundity in Osmia, is subjected to high levels of intrinsic variability, even among females of similar size exposed to identical conditions during development and nesting.

Marrow fat composition in anorexia nervosa

PurposeWomen with anorexia nervosa (AN) have increased marrow fat despite severe depletion of body fat. Recent studies have suggested that marrow fat composition may serve as a biomarker for bone quality. The purpose of our study was to investigate marrow fat composition of the femur using proton MR spectroscopy (1H MRS), and the relationship between measures of marrow fat composition and BMD and body composition in women with AN and normal-weight controls. Materials and methods14 women with AN (29.5±1.9years) and 12 age-matched normal-weight controls underwent 1H MRS to determine total marrow fat content and marrow fat composition of the femoral diaphysis and soleus intramyocellular lipids und unsaturated muscle lipids. MRI was performed to quantify abdominal fat, thigh fat and muscle areas. Lumbar spine BMD, fat and lean mass were assessed by DXA. ResultsSubjects with AN had higher marrow fat content (p<0.05), but similar marrow fat composition (p>0.05) compared to normal-weight controls. There was an inverse association between marrow methylene protons, an estimate of fatty acid (FA) saturated bonds, and lumbar spine BMD (r=−0.52, p=0.008) independent of %ideal body weight (%IBW). Olefinic protons at 5.3ppm, an estimate of FA unsaturated bonds, were inversely associated with body fat depots, independent of %IBW, and positively associated with soleus unsaturation (p≤0.05). ConclusionWomen with AN have higher total femoral marrow fat but similar composition compared to normal-weight controls. The degree of marrow FA saturation correlates inversely with BMD, suggesting that saturated lipids may have negative effects on BMD. The degree of marrow FA unsaturation correlates positively with soleus unsaturation, suggesting that marrow fat composition may be influenced by the same factors as ectopic lipid composition in muscle.

Endocrine aspects of ovary growth and gestation in the Argentinian cockroach, Blaptica dubia (Dictyoptera, Blaberidae)

Titers of juvenile hormone (JH) III and free ecdysteroids were studied in the hemolymph of the ovoviviparous Argentinian cockroach, Blaptica dubia, related to fat body depletion and reproduction. Adult females were analyzed during the first (days 5–25) and second vitellogenic cycle (days 80–100) and during the periods of gestation. Body weight changes of adult females were closely related to ovarian growth, ootheca formation, ootheca deposition, and hatching of the nymphs. Biochemical analysis of the fat body revealed lipids as the main storage compounds, followed by glycogen, proteins, and free carbohydrates. Changes in the fat body weight and in the chemical constituents of the fat body correlated with the processes of vitellogenesis and gestation. Concentrations of JH and free ecdysteroids in the hemolymph were measured by high pressure liquid chromatography-mass spectrometry. JH III was the only JH homolog found. JH III titers were high during vitellogenesis as well as toward the end of the gestation period. Changes in the concentrations of ecdysone and 20-hydroxyecdysone were less clear. The results reveal JH III as the major gonadotropic hormone in adult females of B. dubia.

Influence of Winter Temperature and Simulated Climate Change on Body Mass and Fat Body Depletion During Diapause in Adults of the Solitary Bee, &lt;I&gt;Osmia rufa&lt;/I&gt; (Hymenoptera: Megachilidae)

The influence of simulated climate change on body weight and depletion of fat body reserves was studied during diapause in the European solitary bee Osmia rufa L. (Hymenoptera: Megachilidae). Insects (females) were reared and collected from outdoor nests from September to March. One cohort of females was weighed and dissected immediately for analyses, whereas another cohort was subjected to simulated warmer temperature (15°C for 7 d) before analyses. A gradual decline in body mass and fat body content was recorded with declining temperatures from September to January in female bees from natural conditions. Temperature increased gradually from January to March with a further decline in body mass and fat body content. The fat body development index dropped from five in September-October (≈ 89% individuals) to four for the period from November to February (≈ 84% individuals) and further to three in March (95% individuals) before emergence. Simulated warmer winter temperature also resulted in a similar decline in body weight and fat body content; however, body weight and fat body content declined faster. The fat body development index dropped to three in December in the majority of individuals and continued at this level until March just before emergence. Taken together, our data indicate an earlier depletion of fat body reserves under simulated climate change conditions that may impact ovarian development and reproductive fitness in O. rufa.

Availability of energetic substrates and exercise performance in heart failure with or without diabetes

The goal of the study was to examine whether resting or post-exercise metabolic substrate levels are associated with differential exercise performance and long-term outcome in control subjects or heart failure (HF) patients with or without type 2 diabetes mellitus (DM). Twenty five healthy controls matched with 97 patients with stable advanced HF were prospectively enrolled. Exercise capacity, age, gender, and HF aetiology were balanced between HFDM- and HFDM+ groups. Subjects underwent maximal bicycle spiroergometry with blood sampling to measure metabolites and neurohormones before and immediately after the exercise. HFDM+ patients had increased free fatty acids, glucose, and β-hydroxybutyrate compared with controls. HFDM+ patients had higher baseline copeptin (24 ± 16 vs. 17 ± 13 pmol/L, P < 0.05) but otherwise showed similar neurohumoral activation and exercise response to HFDM- patients. Peak oxygen consumption (VO(2)) was unrelated to post-exercise free fatty acids, glucose, lactate, or glycerol, but strongly correlated with post-exercise pyruvate (in all: r = 0.62, P < 0.001). During the next 17 ± 10 months, 36% of HF patients experienced an adverse event (death, urgent transplantation, or assist device insertion). From metabolic factors, only post-exercise glucose [hazard ratio (HR) 1.28, P = 0.04), total body fat (HR 0.58, P < 0.001), and the presence of DM (HR 1.98, P = 0.04) were predictive of the outcome. With the exception of pyruvate, acute changes of metabolic substrates are not related to cardiac performance in HF, regardless of diabetic status. Inhibition of body fat depletion, attenuation of stress-related hyperglycaemia, or increasing dynamics of plasma pyruvate may represent therapeutic targets in advanced HF.

Young Women with Cold-Activated Brown Adipose Tissue Have Higher Bone Mineral Density and Lower Pref-1 than Women without Brown Adipose Tissue: A Study in Women with Anorexia Nervosa, Women Recovered from Anorexia Nervosa, and Normal-Weight Women

Anorexia nervosa (AN) is associated with depletion of body fat, loss of bone mineral density (BMD), and impaired thermogenesis. Brown adipose tissue (BAT) is lower in obese individuals and decreases during aging. Recent studies have suggested a link between BAT and bone metabolism. Our objective was to investigate the presence and quantity of BAT in patients with AN, recovered AN (AN-R), and normal-weight controls and to study the relationship between BAT and BMD and body composition and investigate hormonal predictors of BAT. This was a cross-sectional study at a clinical research center. Patients included 15 women: five with AN (mean age 30 ± 6.3 yr), five AN-R, and five healthy nonobese controls of comparable age. Cold-activated BAT was determined by fluorodeoxyglucose-positron emission tomography/computed tomography. BMD of total-body, spine, and hip, fat and lean mass was determined by dual-energy x-ray absorptiometry. Single-slice magnetic resonance imaging at L4 was done for abdominal fat compartments, and preadipocyte factor-1 (Pref-1), T₃, and T₄ were measured. Within the AN group, one of five; in the AN-R group, two of five; and in the healthy nonobese control group, four of five subjects were BAT positive. Subjects were divided into groups based on the presence (n = 7) or absence (n = 8) of BAT. Both groups were of comparable age and body mass index. Women with BAT had higher total-body BMD, higher T₃, and lower Pref-1 compared with women without BAT. There was a positive correlation between BAT and BMD that remained significant after controlling for disease status and body mass index. Young women with AN have low cold-activated BAT, which may be due to impaired BAT thermogenesis. Young women with BAT have higher BMD and lower Pref-1 compared with women without BAT, suggesting that BAT may be involved in the regulation of stem cell differentiation into the bone lineage at the expense of adipogenesis.

The long summer: Pre-wintering temperatures affect metabolic expenditure and winter survival in a solitary bee

The impact of climate change on insect populations depends on specific life cycle traits and physiological adaptations. The solitary bee Osmia lignaria winters as a pre-emergent adult, and requires a period of cold temperature for winter diapause completion. It is a univoltine species, and diapause induction does not depend on photoperiod. To understand the potential effects of longer summers on O. lignaria populations, we exposed individuals to three treatments simulating early, mid and late winter arrivals, and measured respiration rates, metabolic expenditure, weight loss, fat body depletion, lipid levels and winter mortality. The early-winter treatment disrupted diapause development, but had no apparent negative effects on fitness. In contrast, late-winter bees had a greater energetic expenditure (1.5-fold), weight (1.4-fold) and lipid (2-fold) loss, greater fat body depletion, and a 19% increase in mortality compared to mid-winter bees. We also monitored adult eclosion and arrival of winter temperatures under natural conditions in four years. We found a positive correlation between mean degree-day accumulation during pre-wintering (a measure of asynchrony between adult eclosion and winter arrival) and yearly winter mortality. Individually, bees experiencing greater degree-day accumulations exhibited reduced post-winter longevity. Timing of adult eclosion in O. lignaria is dependent on the duration of the prepupal period, which occurs in mid-summer, is also diapause-mediated, and is longer in populations from southerly latitudes. In a global warming scenario, we expect long summer diapause phenotypes to replace short summer diapause phenotypes, effectively maintaining short pre-wintering periods in spite of delayed winter arrivals.

Thigh Circumference as a Useful Predictor of Body Fat in Adolescent Girls with Anorexia Nervosa

Background/Aim: Girls with anorexia nervosa (AN) demonstrate severe depletion of body fat. The aim of this study was to determine an accurate anthropometric measurement for clinical assessment of fat depletion in girls with AN in connection with body composition measured by dual-energy X-ray absorptiometry (DXA). Methods: In 64 female AN patients aged 12.8–23.1 years (mean 16.0 ± 1.8), body mass index (BMI), skinfold thickness (subscapular, abdominal and triceps), mid-upper arm and thigh circumference, fat mass (FM) and lean mass were determined and compared with the data of 71 controls. Results: Girls with AN had lower anthropometric traits and were fat depleted compared to controls (14.9 ± 7.3 vs. 27.4 ± 6.4% of FM using DXA; all p < 0.001). BMI, thigh circumference and subscapular skinfold thickness demonstrated a very similar predictive value for DXA assessment of body fat. Based on the receiver-operating characteristic curve analysis and the determination of the positive predictive value, thigh circumference appeared the most specific and sensitive anthropometric predictor of fatness discriminating between AN and healthy girls, with the AUC value reaching 0.95 (95% CI = 0.92–0.97). Using a cutoff value of 49.6 cm, accuracy was 90.6%, sensitivity 93% and specificity 88.7%. Conclusions: Thigh circumference strongly correlates with DXA-FM and demonstrates a slight clinical advantage over BMI. This simple measurement might also serve as a useful predictor of body fatness in adolescent girls with AN and should therefore be further evaluated in independent cohort studies.

Both UDP N-acetylglucosamine pyrophosphorylases of Tribolium castaneum are critical for molting, survival and fecundity

A bioinformatics search of the genome of the red flour beetle, Tribolium castaneum, resulted in the identification of two genes encoding proteins closely related to UDP- N-acetylglucosamine pyrophosphorylases (UAPs), which provide the activated precursor, UDP- N-acetylglucosamine, for the synthesis of chitin, glycoproteins and glycosylphosphoinositide (GPI) anchors of some membrane proteins as well as for the modification of other substrates. This is in contrast to other arthropods whose genomes have been completely sequenced, all of which have only a single copy of this gene. The two T. castaneum UAP genes, TcUAP1 and TcUAP2, share both nucleotide and amino acid sequence identities of about 60%. RT-PCR analysis revealed that the two genes differ in their developmental and tissue-specific patterns of expression. RNA interference (RNAi) indicated roles for TcUAP1 and TcUAP2 at the molt and intermolt stages, respectively: RNAi for TcUAP1 resulted in specific arrest at the larval-larval, larval-pupal or pupal-adult molts, depending on time of injection of double-stranded RNAs, whereas RNAi for TcUAP2 prevented larval growth or resulted in pupal paralysis. Analysis of elytral cuticle indicated loss of structural integrity and chitin staining after RNAi for TcUAP1, but not after RNAi for TcUAP2. Loss of peritrophic matrix (PM)-associated chitin was also observed following RNAi for TcUAP1, but not after RNAi for TcUAP2. Down-regulation of transcripts for either TcUAP gene at the mature adult stage resulted in cessation of oviposition in females, as well as fat body depletion and eventual death in both sexes. These results demonstrate that both TcUAP genes are critical for beetle development and survival, but that only TcUAP1 is clearly associated with synthesis of cuticular or PM chitin. However, both of these genes appear to have additional critical role(s) unrelated to chitin synthesis, presumably in the glycosylation of proteins and/or secondary metabolites.