Sexual and site differences in calcium consumption by the Malabar Giant Squirrel Ratufa indica

Summary The calcium ingestion of Malabar Giant Squirrels Ratufa indica (Sciuridae) was examined at two sites, Magod and Bhimashankar, in western India. In females at Magod a positive correlation was found between rates of calcium ingestion from food resources and the contribution of those resources to the daily diet. This relationship was true for all females at Magod irre-spective of their reproductive condition. This relationship was neither significant for males at the same site nor for both sexes at Bhimashankar. A differential requirement for calcium between the sexes and the occurrence of higher rates of calcium ingestion or the probable presence of more easily digestible calcium at Bhimashankar are postulated to explain the observed phenomenon. Mature leaves and bark appear to be reliable sources of calcium at these sites.     

Evaluation of Drugs for Treating Obesity

Criteria for the evaluation of new drugs to treat obesity are important as guides for designing clinical trials to test these agents. These criteria must be developed in relation to the realities of obesity, which is a chronic disease associated with morbidity and mortality that is increased by visceral fat deposits. The observation that patients regain weight after stopping drug treatment for obesity argues for the proposition that drugs work only when taken and NOT that the drugs are ineffective. The analogy between the development of treatments for obesity to those for the treatment of hypertension is used to highlight potential areas for new developments. Several features of an ideal drug for the treatment of obesity are suggested. Criteria for evaluating new drugs include both primary and secondary endpoints. The primary endpoint for an anti-obesity drug should be weight loss, possibly by category of success. Losses of total body fat or visceral fat might be alternative primary endpoints. Secondary endpoints include reduction in risk factors for associated diseases and improvement in the quality of life. In trials where vigorous placebo designs including highly aggressive behavior modification or very-low-calorie diets were used, it may be difficult or impossible to detect a response to a drug.     

Cholecystokinin-octapeptide suppresses stress-induced eating by inducing hyperglycemia

Intracerebroventricular administration of cholecystokinin-octapeptide (CCK-8) in unanesthetized, unrestrained rats suppressed stress-induced eating and produced hyperglycemia. Prior adrenalectomy markedly reduced the hyperglycemia effect of intraventricular CCK-8 and also decreased the suppressive effect of CCK-8 on stress-induced eating. Our data are compatible with the anorectic effect of CCK-8 being secondary to the hyperglycemia it produces.     

The role of estradiol in adrenal insufficiency and its interaction with corticosterone on hydromineral balance

Estradiol (E2) plays an important role in controlling the homeostasis of body fluids. Several studies have reported the involvement of the hypothalamic pituitary adrenal axis (HPA) in the homeostatic control of hydromineral balance and the influence of estrogens on the modulation of this system. Nevertheless, until now, the physiological relevance of HPA axis activity on the hydromineral balance in females has not yet been fully elucidated. Therefore, the objective of the present study was to evaluate the effects of E2 (20 μg/animal) pretreatment on neuroendocrine and hydroelectrolyte changes induced by adrenalectomy (ADX) with or without glucocorticoid hormone replacement (corticosterone, CORT; 10 mg/kg) in ovariectomized rats (OVX). The results show that sodium appetite, natriuresis and the elevated plasma angiotensin II (ANG II) concentration induced by ADX were attenuated by E2 pretreatment. Additionally, a reduction of AT1 mRNA expression in the subfornical organ (SFO) and an increase in plasma atrial natriuretic peptide (ANP) concentrations by E2 pretreatment were observed. E2 pretreatment reversed the reduction in water intake induced by ADX in ADX CORT-replaced rats. Moreover, E2 pretreatment attenuated corticotropin releasing factor (CRF) mRNA expression in the paraventricular nucleus (PVN) induced by ADX. In contrast, E2 pretreatment increased CRF mRNA expression in the PVN in ADX CORT-replaced rats. Taken together, these results suggest that E2 has an important role in the modulation of behavioral and neuroendocrine responses involved in the maintenance of body fluid homeostasis in ADX rats with or without glucocorticoid replacement therapy.     

The daidzein- and estradiol- induced anorectic action in CCK or leptin receptor deficiency rats

We investigated the effect of daidzein feeding and estradiol treatment on food intake in cholecystokinin-1 receptor (CCK1R) deficiency, leptin receptor (ObRb) deficiency rats and their wild-type rats. These rats underwent an ovariectomy or a sham operation. For the 5 week experiment, each rat was divided in three groups: control, daidzein (150 mg/kg diet), and estradiol (4.2 μg/rat/day) groups. In both CCK1R+ and CCK1R? rats, daidzein feeding and estradiol treatment significantly decreased food intake. Daidzein feeding significantly reduced food intake in ovariectomized ObRb? rats, although not in ObRb+ rats. Estradiol treatment significantly lowered food intake in ovariectomized ObRb+ and ObRb? rats. In the ovariectomized rats, estradiol treatment significantly increases uterine weight, while daidzein feeding did not change it, suggesting that daidzein might have no or weak estrogenic effect in our experiment. These results suggest that CCK1R and ObRb signalings were not essential for the daidzein- and estradiol-induced anorectic action.     

Short-term effects of a "health-at-every-size" approach on eating behaviors and appetite ratings

Objective: To assess the effects of a “Health‐At‐Every‐Size” (HAES) intervention on eating behaviors and appetite ratings in 144 premenopausal overweight women. Research Methods and Procedures: Women were randomly assigned to one of the 3 groups: HAES group, social support (SS) group, and control group (N = 48 in each group). Interventions were conducted over a 4‐month period, and measurements were taken before and after this period. Eating behaviors (cognitive dietary restraint, disinhibition, and susceptibility to hunger) were evaluated by the Three‐Factor Eating Questionnaire. Appetite ratings (desire to eat, hunger, fullness, and prospective food consumption) were assessed by visual analogue scales before and after a standardized breakfast. Results: More important decreases in susceptibility to hunger and external hunger were observed in the HAES group when compared with the SS group (p = 0.05, for susceptibility to hunger) and the control group (p = 0.02 and p = 0.005, for susceptibility to hunger and external hunger, respectively). In addition, women from the HAES group had more important decreases in postprandial area under the curve for desire to eat (p = 0.02) and hunger (p = 0.04) when compared with the control group. The change in the desire to eat noted in the HAES group was also different from the one observed in SS group (p = 0.02). Women from the HAES group experienced significant weight loss at 4 months (?1.6 ± 2.5 kg, p < 0.0001), which did not differ significantly from the SS and control groups (p = 0.09). An increase in flexible restraint was significantly related to a greater weight loss in both HAES and SS groups (r = ?0.39, p < 0.01; and r = ?0.37, p < 0.05, respectively). A decrease in habitual susceptibility to disinhibition was also associated with a greater weight loss in HAES and control groups (r = 0.31, p < 0.05; and r = 0.44, p < 0.05, respectively). Discussion: These results suggest that a HAES intervention could have significant effects on eating behaviors and appetite ratings in premenopausal overweight women, when compared with an SS intervention or a control group.     

Does a High‐protein Diet Improve Weight Loss in Overweight and Obese Children?

Objective: To evaluate the effect of a high‐protein diet on anthropometry, body composition, subjective appetite, and mood sensations in overweight and obese children attending a residential weight‐loss camp. Research Methods and Procedures: Children (120; BMI, 33.1 ± 5.5 kg/m²; age, 14.2 ± 1.9 years) were randomly assigned to either a standard or high‐protein diet group (15% vs. 22.5% protein, respectively). All children were assessed at baseline and at the end of the camp for anthropometry, body composition, blood pressure, biochemical variables (n = 27), and subjective appetite and mood sensations (n = 50). Results: Attendance at the weight‐loss camp resulted in significant improvements in most measures. Campers lost 5.5 ± 2.9 kg in body weight (p < 0.001) and 3.8 ± 5.4 kg in fat mass (p < 0.001) and reduced their BMI standard deviation score by 0.27 ± 0.1 (p < 0.001) and their waist circumference by 6.6 ± 2.8 cm (p < 0.001). Subjective sensations of hunger increased significantly over the camp duration, but no other changes in appetite or mood were observed. There were no significant differences between the two diets on any physical or subjective measures. Discussion: Weight‐loss camps are effective in assisting children to lose weight and improve on a range of health outcomes, independently of the protein content of the diet. The implications of an increase in hunger associated with weight loss needs to be considered. Further work is warranted to investigate whether higher levels of dietary protein are feasible or effective in longer‐term weight‐loss interventions of this type.     

Effects of acute and chronic protein intake on metabolism, appetite, and ghrelin during weight loss

Objective: This study evaluated the effects of acute and chronic consumption of higher dietary protein on energy expenditure, macronutrient use, appetite, and appetite‐regulating hormones during weight loss in women. Research Methods and Procedures: Thirty‐eight women chronically consuming a 750 kcal/d energy‐deficit diet with a protein content of 30% (higher protein‐chronic diet, HP‐CD, n = 21) or 18% (normal protein‐chronic diet, NP‐CD, n = 17) for 9 weeks were tested. On separate days, metabolic, appetite, and hormonal responses were measured over 4 hours when the women consumed a higher protein‐acute meal (HP‐AM) (30% of energy as protein) or a normal protein‐acute meal (NP‐AM) (18% of energy as protein). Results: With chronic diet groups combined, HP‐AM led to lower respiratory exchange ratio (0.829 ± 0.005 vs. 0.843 ± 0.008; p < 0.05), lower carbohydrate oxidation (p < 0.05), and higher fat oxidation (p < 0.05) compared with NP‐AM. HP‐AM also led to reduced self‐reported postprandial hunger (p < 0.001) and desire to eat (p < 0.001) and lower postprandial ghrelin (252 ± 16 vs. 274 ± 18 ng/mL · 240 minutes, p < 0.05) compared with NP‐AM. No differences in postprandial energy expenditure (PPEE) occurred between meals. When combining acute meals, respiratory exchange ratio was lower (p < 0.05) and protein oxidation (p < 0.001) was higher in the HP‐CD vs. NP‐CD. An acute meal‐by‐chronic diet interaction was observed with PPEE such that HP‐AM led to greater PPEE in the HP‐CD vs. NP‐CD (28.7 ± 2.7 vs. 19.9 ± 2.7 kcal/min for 195 minutes; p < 0.05). Conclusions: During weight loss, thermogenesis and protein use appear to be influenced by chronic protein intake, while appetite and ghrelin are more responsive to acute protein intake.     

温度对小斑熊虫Milnesium tardigradum Doyère(缓步动物门,小斑熊虫科)食量和食物消化率的影响

为研究温度对小斑熊虫Milnesium tardigradum食量和食物消化率的影响,以轮虫为食物,将20只小斑熊虫分成两组,每组10只,分别在20℃和5℃下驯化饲养10天,并在各自驯化温度下进行实验观察。对实验结果的方差分析和t-检验表明,小斑熊虫的食量随温度的升高而显著增加,20℃下饲养的个体取食轮虫的个数比5℃下的多0.84个/天;小斑熊虫的食物消化率随温度的升高而显著增加,20℃下的小斑熊虫消化率比5℃下的快24 h。     

Serial Echocardiographic and Clinical Evaluation of Valvular Regurgitation Before,During, and After Treatment with Fenfluramine or Dexfenfluramine and Mazindol or Phentermine

RYAN, DONNA H., GEORGE A. BRAY, FRED HELMCKE, GARY SANDER, JULIA VOLAUFOVA, FRANK GREENWAY, PRAMILLA SUBRAMANIAM, AND D. LUKE GLANCY. Serial echocardiographic and clinical evaluation of valvular regurgitation before, during, and after treatment with fenfluramine or dexfenfluramine and mazindol or phentermine. Obes Res. Objective: The prevalence of cardiac valvular regurgitation demonstrated by echocardiography in patients who took appetite-suppressant medication for weight loss has been assessed at 5%-30%. We studied 86 patients who had echo-cardiograms before treatment with appetite suppressants to determine the incidence of new cases and to evaluate the clinical implication of the echocardiographic findings. Research Methods and Procedures: We studied 69 men [Mean± Standard Deviation (S) age 49±81] and 17 women (mean±S age 50±7) who had 233 echocardiograms before, during, and after a weight-loss program that used predominantly fenfluramine (or dexfenfluramine) with mazindol (or phentermine). Mean drug exposure was 17 months. Blinded echocardiographic readings were performed to identify and grade aortic regurgitation (AR) or mitral regurgitation (MR). Results: Seven of 86 patients (8%) had pre-existing regurgitation with five (6%) meeting our case definition. Thirteen (16. 5%) of initially normal patients developed valvular regurgitation and were new cases. Of the new cases, 12 were grade IAV AR and one was both grade II/III MR and IIDV AR. All 13 patients were asymptomatic, and only two aortic insufficiency murmurs could be auscultated. There was significantly greater risk for developing valvulopathy for those who took medications longer than 6 months (p = 0. 03), and no new cases were observed in patients exposed for less than 8 months. No increased risk associated with age, presence of hypertension, or exposure to fenfluramine-phentermine combination was demonstrated. Although there was a higher incidence of new regurgitation in women (31% vs. 13% for men), this was not statistically significant (p = 0. 093). Discussion: Some patients who had normal echocardiograms at baseline developed cardiac valvular regurgitation after exposure to fenfluramine or dexfenfluramine with mazindol or phentermine. The development of valvulopathy was significantly correlated with duration of exposure. The clinical implications of echocardiographically demonstrated regurgitation are uncertain, since there were only two audible murmurs and no other clinically relevant signs or symptoms among the patients.