Dexfenfluramine: action with estradiol on food intake and body weight in ovariectomized rats

1990 ◽  
Vol 258 (1) ◽  
pp. R211-R215 ◽  
Author(s):  
A. M. Souquet ◽  
N. E. Rowland

Previous work from this laboratory has shown that chronic administration of dexfenfluramine (DF) caused substantial weight loss in rats that were overweight 3-4 mo after ovariectomy (OVX), but not in OVX rats that were of normal weight, as a result of estrogen replacement. The present study was conducted to determine whether the enhanced weight loss in the former group is because of either overweight per se or an inhibitory effect of estrogen on DF. Starting either 0, 6, or 14 wk after OVX, when weight gain was zero, moderate, or near maximal, respectively, rats received a 12-day regimen of either estradiol or the oil vehicle and either DF (3 mg.kg-1.day-1 by osmotic minipump) or no drug. DF had no effect on either food intake or weight gain of groups treated during 0-2 wk after OVX but had significant anorectic and weight loss actions in groups treated 6-8 and 14-16 wk after OVX. Estrogen had a similar effect at all three times and in the 14-wk group produced an effect that was additive with that of DF. Measures of plasma glucose and triglycerides and adipose tissue lipoprotein lipase activity did not correlate with the effectiveness of the drug to promote weight loss.

2020 ◽  
Author(s):  
Qing-Song Xia ◽  
Fan Wu ◽  
Ming-Ming Gong ◽  
Yan Zhao ◽  
Ding-Kun Wang ◽  
...  

Abstract Objective: The observational study was intended to explore the weight changes and risk factors of weight gain during the self-quarantine and find available methods to lose weight.Method: This was an online retrospective observational study investigating the weight changes before and after home confinement. A total of 530 participants completed the online questionnaire. diet, sleep, self-reported depression, disease history and exercise information possibly relating to weight changes were incorporated into the questionnaire. The differences among four groups (underweight, normal weight, overweight and obesity) in BMI change and weight change were compared, and the risk factors of weight gain was also analyzed by multiple linear regression analysis. Result: Participants were mostly between 21-50 years old, getting an average weight change of 0.82±3.31kg, and an average BMI change of 0.35 [-0.37, 1.00]. 43.77% of them gained weight by 2.99±2.29kg averagely. People with normal weight were easier to gain weight than obese group (p=0.001). There were differences in food intake (p<0.001), eating habits(p<0.001), taste preference (p=0.047), daily exercise step change(p=0.007), exercise (p=0.02) between non-weight gain group and weight gain group. The multiple linear regression revealed that weight gains were associated with sex (p=0.002), food intake (p=0.004), current daily exercise step (p=0.009) and self-reported depression (p=0.002) and weight loss was related to food intake (p=0.004) and pre-BMI (p=0.001).Conclusion: Eating irregularly, increasing food intake, self-reported depression and decreased daily steps were risk factors of weight gain, yet weight loss was related to decreased food intake and pre-BMI.


2005 ◽  
Vol 75 (2) ◽  
pp. 156-160 ◽  
Author(s):  
Melton ◽  
Keenan ◽  
Stanciu ◽  
Hegsted ◽  
Zablah-Pimentel ◽  
...  

In this five-week study, we tested the hypotheses that free access to a maintenance diet supplemented with L-carnitine (L-C) would reduce body fat in adult, sedentary, ovariectomized (OVX) rats, and that there would be an additive effect of L-C on weight reduction in swim-trained animals. As expected, serum carnitine was higher in rats fed the L-C diet, and the OVX-induced weight gain and abdominal fat were counteracted by swimming. L-C supplementation did not reduce the weight gain or abdominal fat in these adult female rats. Moreover, though not reaching statistical significance, rats that were fed L-C demonstrated a tendency for greater weight gain than their basal-fed counterparts despite no difference in energy intake. If the results of this study on ovariectomized rats can be translated to postmenopausal women, moderate intensity exercise may be recommended, but L-C supplementation, with no energy restriction, may be contraindicated as a weight loss method in this cohort.


1993 ◽  
Vol 264 (6) ◽  
pp. R1214-R1218 ◽  
Author(s):  
J. M. Gray ◽  
S. Schrock ◽  
M. Bishop

Treatment of ovariectomized rats for 3 days with 2 micrograms estradiol benzoate (E2B), 6 micrograms ethinyl estradiol, or 1-2 mg of either of the antiestrogens nafoxidine or tamoxifen led to similar decreases in food intake, body weight gain, adipose tissue lipoprotein lipase activity, and hepatic fatty acid synthetase activity, despite their different effects on uterine growth and induction of progestin receptors in pituitary and adipose tissue. Longer-term (2 wk) treatment with tamoxifen resulted in similar transient changes in food intake and body weight gain, as did treatment with E2B. Daily administration of 50 micrograms fluphenazine (FLU) led to significant decreases in body weight, although there was no change in food intake. Concurrent administration of FLU with either E2B or tamoxifen led to additive effects on body weight and food intake change. None of the treatments had any effect on in vitro binding of [3H]tamoxifen to antiestrogen binding sites in pooled hypothalamic-preoptic area samples.


1981 ◽  
Vol 240 (5) ◽  
pp. E474-E481 ◽  
Author(s):  
J. M. Gray ◽  
G. N. Wade

A series of experiments examined the effects of two progestins, progesterone and R 5020, and two nonsteroidal antiestrogens, nafoxidine and MER-25, on body weight and composition in female rats. Both progesterone and R 5020 increased food intake, body weight, and carcass adiposity in ovariectomized (OVX) rats treated with estradiol benzoate (EB), but neither progestin had any effect on these measures in OVX rats not treated with EB. R 5020 was substantially more effective than progesterone on all end points. Nafoxidine and MER-25 mimicked the actions of estradiol and decreased adipose tissue lipoprotein lipase (LPL) activity by 75–80%. For adipose tissue LPL activity, both nafoxidine and MER-25 were full estrogen agonists and without antiestrogenic activity. Nafoxidine also mimicked the effects of EB by reducing food intake, body weight, and carcass adiposity in OVX rats. In contrast, nafoxidine antagonized the induction of cytoplasmic progestin ([3H]R 5020) binding sites by EB in parametrial adipose tissue of OVX rats. In nafoxidine-treated OVX rats, concurrent progesterone administration had no effect on adipose tissue LPL activity, but progesterone did increase food intake, body weight, and carcass fat content. Some physiological mechanisms by which gonadal steroids may act to influence eating and adiposity are discussed.


1983 ◽  
Vol 245 (3) ◽  
pp. E211-E219 ◽  
Author(s):  
I. Ramirez ◽  
M. I. Friedman

Rats were given daily injections of protamine-zinc insulin (PZI) that increased food intake and body weight. Termination of insulin treatment resulted in transient hypophagia and weight loss. Simultaneously with the weight loss, plasma levels of glycerol, free fatty acids, glucose, and ketones increased, whereas adipose tissue lipoprotein lipase activity and liver glycogen decreased. These changes in food intake and metabolism after termination of PZI treatment were accentuated in streptozotocin-diabetic rats. Two antilipolytic drugs (nicotinic acid and 3,5-dimethylpyrazole) blocked the elevation in plasma glycerol while having no effect on food intake. A 1-day fast after termination of insulin treatment equalized insulin-treated and control groups for plasma glycerol and ketones and reversed group differences in free fatty acids; the elevation in plasma glucose persisted despite starvation. Following starvation, previously PZI-treated rats ate less than controls on refeeding. The results show that enhanced lipolysis does not invariably accompany hypophagia during excess weight loss and suggest that a disturbance in carbohydrate metabolism or an increase in hepatic fatty acid oxidation may underlie this decrease in food intake.


2008 ◽  
Vol 103 (1) ◽  
pp. 35-47 ◽  
Author(s):  
Ingo Wegener ◽  
Astrid Wawrzyniak ◽  
Katrin Imbierowicz ◽  
Rupert Conrad ◽  
Jochen Musch ◽  
...  

Attenuated affective processing is hypothesized to play a role in the development and maintenance of obesity. Using an affective priming task measuring automatic affective processing of verbal stimuli, a group of 30 obese participants in a weight-loss program at the Psychosomatic University Clinic Bonn ( M age = 48.3, SD = 10.7) was compared with a group of 25 participants of normal weight ( M age = 43.6, SD= 12.5). A smaller affective priming effect was observed for participants with obesity, indicating less pronounced reactions to valenced adjectives. The generally reduced affective processing in obese participants was discussed as a possible factor in the etiology of obesity. Individuals who generally show less pronounced affective reactions to a given stimulus may also react with less negative affect when confronted with weight gain or less positive affect when weight is lost. Consequently, they could be expected to be less motivated to stop overeating or to engage in dieting and will have a higher risk of becoming or staying obese.


1979 ◽  
Vol 236 (2) ◽  
pp. E105 ◽  
Author(s):  
K T Borer ◽  
N Rowland ◽  
A Mirow ◽  
R C Borer ◽  
R P Kelch

Physiological and behavioral responses of adult hamsters to starvation were studied by measuring food intake, weight recovery, serum concentrations of glucose, insulin, free fatty acids and beta-hydroxybutyrate, and ketonuria in animals subjected to different weight losses, diets, and durations of fast. Hamsters were debilitated by fasts longer than 12 h or leading to greater than 20% weight loss. Hamsters' feeding patterns were unmodified by fasts ranging between 5 and 12 h and showed no circadian periodicity. Hamsters predominantly recovered from weight losses without increasing their food consumption (unless they were offered a diet of pellets and seeds) and without changing their meal patterns, at a rate of weight gain proportional to the magnitude of preceding weight loss if provided with uninterrupted access to food. By 8 h of fast, blood metabolites were indicative of mobilization of body fat. Hamsters are thus behaviorally unresponsive to duration of fast, but compensate physiologically for weight losses with proportional increases in the rate of weight gain.


2007 ◽  
Vol 293 (5) ◽  
pp. R1798-R1808 ◽  
Author(s):  
Prasanth K. Chelikani ◽  
Alvin C. Haver ◽  
Roger D. Reidelberger

Chronic administration of anorexigenic substances to experimental animals by injections or continuous infusion typically produces no effect or a transient reduction in daily food intake and body weight. Our aim was to identify an intermittent dosing strategy for intraperitoneal infusion of salmon calcitonin (sCT), a homolog of amylin that produces a sustained 25–35% reduction in daily food intake and adiposity in diet-induced obese rats. Rats (649 ± 10 g body wt, 27 ± 1% body fat), with intraperitoneal catheters tethered to infusion swivels, had free access to a 45% fat diet. Food intake, body weight, and adiposity during the 7-wk test period were relatively stable in the vehicle-treated rats ( n = 16). None of 10 sCT dosing regimens administered in succession to a second group of rats ( n = 18) produced a sustained 25–35% reduction in daily food intake for >5 days, although body weight and adiposity were reduced by 9% (587 ± 12 vs. 651 ± 14 g) and 22% (20.6 ± 1.2 vs. 26.5 ± 1.1%), respectively, across the 7-wk period. The declining inhibitory effect of sCT on daily food intake with the 6-h interinfusion interval appeared to be due in part to an increase in food intake between infusions. The declining inhibitory effect of sCT on daily food intake with the 2- to 3-h interinfusion interval suggested possible receptor downregulation and tolerance to frequent sCT administration; however, food intake increased dramatically when sCT was discontinued for 1 day after apparent loss of treatment efficacy. Together, these results demonstrate the activation of a potent homeostatic response to increase food intake when sCT reduces food intake and energy reserves in diet-induced obese rats.


2017 ◽  
Vol 42 (6) ◽  
pp. 605-612 ◽  
Author(s):  
Maria Fernanda Cury Rodrigues ◽  
Fabiano Candido Ferreira ◽  
Natália Santanielo Silva-Magosso ◽  
Marina Rodrigues Barbosa ◽  
Markus Vinicius Campos Souza ◽  
...  

Estrogen deficiency is directly related to central obesity and low-grade inflammation. Hormonal replacement and exercise training are both able to decrease fat accumulation and inflammation in postmenopausal women. However, the efficiency of resistance training (RT) and estrogen replacement (ER) in minimizing adiposity and inflammation in the visceral adipose tissue (VAT) of ovariectomized (OVX) rats has not yet been elucidated. In this study, Sprague–Dawley rats were divided into the following 6 groups: sham-operated sedentary (Sham-Sed), OVX-Sed, Sham-RT, OVX-RT, OVX-Sed-ER, and OVX-RT-ER groups. ER was performed by implanting silastic capsules containing 17β-estradiol. For RT, the animals were required to climb a 1.1-m vertical ladder with conical flasks containing weights attached to their tails for 12 weeks. Histological analyses were used to evaluate morphological changes. Gene expression levels were determined by quantitative real-time reverse transcriptase polymerase chain reaction, and protein concentrations were determined using Multiplex/Luminex assays. Ovariectomy increased the body mass (BM), adipocyte area, and inflammation in the VAT, the latter of which was indicated by reduced interleukin-10 (48%) and increased tumor necrosis factor (TNF)-α concentration (∼3%). RT efficiently decreased BM, adipocyte area, and inflammation in the OVX groups. The combination of RT and ER decreased BM (19%) and the TNF-α concentration (18%) and increased the gene and protein expression levels of adiponectin (173% and 18%). These results indicate that RT and the combination of RT and ER are efficient strategies for reducing the BM and improving the inflammatory status of OVX rats.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Jia Yang ◽  
Li-juan Xiong ◽  
Fei Xu ◽  
Xiang Zhao ◽  
Bo Liu ◽  
...  

Objective.To study the effects of estrogen on colon polyp formation, proliferation, and angiogenesis on a rat model of colon cancer induced by dimethylhydrazine (DMH).Methods.Thirty-six female ovariectomized (OVX) rats were randomly divided into 3 groups: (I) control group (administrated with vehicles weekly), (II) DMH group (administrated with DMH weekly), and (III) DMH + E2group (administrated with DMH and 17β-estradiol weekly). The incidence, volumes, and multiplicity of colon polyps in each group were evaluated. The microvessel density (MVD), the expressions of Proliferating Cell Nuclear Antigen (PCNA), and the expressions of HIF-1αand VEGF in polyps were detected in each group.Results.Estrogen reduced the multiplicity, volumes, and the PCNA expressions of DMH-induced colon polyps. The MVD in DMH + E2group was significantly lower than that in DMH group. Estrogen treatment decreased the HIF-1αand VEGF expressions at both mRNA and protein level.Conclusion.Estrogen replacement was protective for ovariectomized rats from DMH-induced carcinogenesis, and one of the mechanisms for this was due to estrogen’s inhibitive effects on blood vessel formation by downregulating VEGF and HIF-1αexpressions.


Sign in / Sign up

Export Citation Format

Share Document