Potential Usefulness of a Wakame/Carob Functional Snack for the Treatment of Several Aspects of Metabolic Syndrome: From In Vitro to In Vivo Studies.

Metabolic syndrome (MetS) greatly increases the risk of cardiovascular diseases and type 2 diabetes mellitus. The aim of this study was to evaluate the efficacy of functional snacks containing a combination of wakame (W) and carob pod (CP) flours in reducing markers associated with MetS. The mechanisms of action underlying these effects were also evaluated. In vitro approaches were carried out in mature 3T3-L1 adipocytes and RAW 264.7 macrophages treated with different doses of extracts from W, CP, or a combination of both. Furthermore, an in vivo experiment was conducted in rats with MetS treated with normal-caloric diets containing different snack formulations with combinations of 1/50 (snack A) or 1/5 of wakame/carob (snack B). In vitro experiments results indicated that both W and CP had delipidating effects, but only the latter induced anti-inflammatory and anti-hypertensive effects. As far as the in vivo study is concerned, snack B was ineffective and snack A showed an anti-hypertensive effect in rats with MetS. The present study shows for the first time the in vitro efficacy of a W and CP combination as an anti-inflammatory, delipidating, and anti-hypertensive tool, and its potential usefulness in treating MetS.

The combination of resveratrol and conjugated linoleic acid is not useful in preventing obesity

No disponible

Scientific research is constantly looking for new molecules to be used as functional ingredients to combat obesity. The aim of the present study was to analyse whether resveratrol and conjugated linoleic acid (CLA) together could reduce body fat more efficiently than their separate administration. Thirty-six male Wistar rats were randomly divided into four groups: controls rats (C), rats treated with resveratrol (RSV), rats treated with CLA (CLA) and rats treated with a combination of resveratrol and CLA (RSV+CLA). All rats were fed on an obesogenic diet. In RSV and RSV+CLA groups, the rats received 30 mg resveratrol/kg body weight/day. In CLA and RSV+CLA groups, an equimolecular mixture of trans-10,cis-12 and cis-9,trans-11 was added to the diet to reach 0.5% of the active isomer trans-10,cis-12. After 6 weeks of treatment, white adipose tissue from different anatomical locations was dissected and weighed. Serum triacylglycerols, total and HDL cholesterols, glucose, insulin, fructosamine and TNF-á were measured. A glucose tolerance test was also performed. Separately, resveratrol and CLA significantly reduced body fat but did not do so when combined: 20% in the RSV group and 18% in CLA group but 7% in the RSV+CLA group. Resveratrol reduced serum triacylglycerols. No differences were found among groups in serum cholesterol. Resveratrol, as well as the combination RSV+CLA, improved glycaemic control. These results demonstrate that the combination RSV+CLA reduces the effectiveness of each compound on body fat-lowering action, but it maintains the positive effect of resveratrol on glycaemic control. Consequently, this combination has no usefulness in obesity prevention (AU)

The combination of resveratrol and conjugated linoleic acid is not useful in preventing obesity.

Scientific research is constantly looking for new molecules to be used as functional ingredients to combat obesity. The aim of the present study was to analyse whether resveratrol and conjugated linoleic acid (CLA) together could reduce body fat more efficiently than their separate administration. Thirty-six male Wistar rats were randomly divided into four groups: controls rats (C), rats treated with resveratrol (RSV), rats treated with CLA (CLA) and rats treated with a combination of resveratrol and CLA (RSV+CLA). All rats were fed on an obesogenic diet. In RSV and RSV+CLA groups, the rats received 30 mg resveratrol/kg body weight/day. In CLA and RSV+CLA groups, an equimolecular mixture of trans-10,cis-12 and cis-9,trans-11 was added to the diet to reach 0.5% of the active isomer trans-10,cis-12. After 6 weeks of treatment, white adipose tissue from different anatomical locations was dissected and weighed. Serum triacylglycerols, total and HDL cholesterols, glucose, insulin, fructosamine and TNF-α were measured. A glucose tolerance test was also performed. Separately, resveratrol and CLA significantly reduced body fat but did not do so when combined: 20% in the RSV group and 18% in CLA group but 7% in the RSV+CLA group. Resveratrol reduced serum triacylglycerols. No differences were found among groups in serum cholesterol. Resveratrol, as well as the combination RSV+CLA, improved glycaemic control. These results demonstrate that the combination RSV+CLA reduces the effectiveness of each compound on body fat-lowering action, but it maintains the positive effect of resveratrol on glycaemic control. Consequently, this combination has no usefulness in obesity prevention.

Effects of trans-10,cis-12 CLA on liver size and fatty acid oxidation under energy restriction conditions in hamsters.

OBJECTIVE: Little evidence exists concerning the effects of trans-10,cis-12 conjugated linoleic acid (CLA) under energy restriction. Thus, the effects of this CLA isomer on adipose tissue size, liver composition, as well as on expression and activity of carnitine-palmitoyl transferase I (CPT-I) and acyl CoA oxidase (ACO), in hamsters fed an energy-restricted diet were analyzed. METHODS: Hamsters were fed a high-fat diet for 7 wk and then subjected to 25% energy-restricted diets supplemented with 0.5% linoleic acid or 0.5% trans-10,cis-12 CLA for 3 wk. Serum insulin, free-triiodothyronine and non-esterified fatty acid levels, liver triacylglycerol, protein and water contents, and CPT-I, ACO, and Peroxisome proliferator-activated receptor alpha (PPARα) expressions and enzyme activities were assessed. RESULTS: Energy restriction reduced liver size, serum levels of insulin, free-triiodothyronine, and non-esterified fatty acid and increased CPT-I activity. Liver composition was not modified. No differences were found between both restricted groups, with the exception of CPT-I and ACO oxidative enzyme activities, which were greater in hamsters fed the CLA diet. CONCLUSIONS: Energy restriction does not cause trans-10,cis-12 CLA to induce liver hyperplasia. Although this CLA isomer increases liver CPT-I and ACO activities, this effect does not result in reduced hepatic triacylglyerol content or decreased adipose tissue size. Consequently, this CLA isomer seems not to be a useful tool for inclusion in body weight loss strategies followed during obesity treatment.

Weak effect of trans-10, cis-12-conjugated linoleic acid on body fat accumulation in adult hamsters.

It has been proposed that young animals and subjects are more responsive to conjugated linoleic acid (CLA) than the adults. Nevertheless, there is very little information concerning the effectiveness of CLA in adult animals. In the present study we aimed to explore the effects of trans-10, cis-12-CLA on body fat accumulation in adult hamsters, as well as on some of the molecular mechanisms described in young animals as responsible for the CLA body fat-lowering effect, such as lipogenesis, lipoprotein lipase (LPL)-mediated fat uptake and thermogenesis. The experiment was conducted with sixteen adult male Syrian Golden hamsters (aged 8 months) fed a high-fat diet supplemented or not with 0.5 % trans-10, cis-12-CLA for 6 weeks. Acetyl-CoA carboxylase (ACX), fatty acid synthase (FAS), LPL, PPARgamma, sterol regulatory element-binding protein (SREBP)-1a and SREBP-1c expressions were assessed in subcutaneous and perirenal adipose tissues by real-time RT-PCR. Total and heparin-releasable LPL activities were determined in subcutaneous adipose tissue by fluorimetry and FAS activity by spectrophotometry. Uncoupling protein-1 (UCP1) expression in interscapular brown adipose tissue was assessed by Western blot. Hamsters fed the trans-10, cis-12-CLA diet showed a significant reduction in subcutaneous adipose tissue. No changes were observed in the expression of ACX, FAS, LPL, SREBP-1a, SREBP-1c and PPARgamma, nor in total and heparin-releasable LPL and FAS activities. Trans-10, cis-12-CLA induced a significant increase in the amount of UCP1. These results suggest a low responsiveness to trans-10, cis-12-CLA in adults, lower than that in young hamsters. One of the reasons explaining this difference is the lack of effect on LPL.

Effects of high-fat high-sucrose feeding, energy restriction, and trans-10,cis-12 conjugated linoleic acid on visfatin and apelin in hamsters.

OBJECTIVE: To analyze the effects of high-fat high-sucrose (HFHS) feeding, energy restriction, and trans-10,cis-12 conjugated linoleic acid (CLA) on visfatin and apelin. DESIGN: A randomized dietary intervention study. SETTING: Free-living individuals studied in metabolic cages. SUBJECTS: Thirty-two male Syrian Golden hamsters (82.6 +/- 1.4 g). INTERVENTIONS: Standard and HFHS feeding for 7 weeks. After that, some hamsters fed the HFHS diet were submitted for 3 weeks to a 25% energy restriction with or without trans-10,cis-12 CLA supplementation (0.5%). RESULTS: Feeding animals an HFHS diet resulted in increased body fat and reduced insulin sensitivity. No changes were observed in the expression and serum levels of visfatin and apelin, or in peroxisome proliferator-activated receptor (PPAR)gamma and Sirt1 expression. Energy restriction reduced body fat and normalized insulin sensitivity. Visfatin showed increased serum levels without changes in expression. No modifications were found as far as apelin was concerned. Sirt1 expression was increased, and PPARgamma remained unchanged. With regard to trans-10,cis-12 CLA, no changes were induced by its addition to the restricted diet. CONCLUSIONS: Insulin function impairment induced by HFHS feeding is not mediated by visfatin and apelin. However, visfatin can play a role in improving insulin sensitivity associated with energy restriction. These results suggest that visfatin may not have evolved as a molecule that reserves the action of insulin when food is widely available, but rather that its function seems to be associated with energy restriction adaptation. In general terms, trans-10,cis-12 CLA did not modify changes induced by energy restriction.

Effects of fluoxetine administration on regional galanin expression in obese Zucker rat hypothalamus.

The aim of the present work was to study the potential involvement of hypothalamic galanin system in the anorectic mechanism of fluoxetine in obese Zucker rats. Male obese Zucker (fa/fa) rats were administered fluoxetine (10 mg/kg; i.p.) daily for two weeks. The control group was given 0.9% NaCl solution. Significant decreases in food intake, final body weight and total body fat were observed after fluoxetine treatment. Although fluoxetine-treated rats showed a decrease in urine elimination, this effect was not enough to compensate decreased water intake, leading to dehydration, as showed by decreased body water content. Chronic fluoxetine administration increased the numbers of galanin positively immunostained neural cells in medial and lateral preoptic areas, lateral hypothalamic area and paraventricular nucleus (rostral and magnocellular regions), without changes in dorsomedial, ventromedial, supraoptic, suprachiasmatic and arcuate nuclei. Taken into account that galanin stimulates appetite, these results could represent rather a compensatory response against reduced food intake than a direct anorectic mechanism. Changes in the magnocellular region of the hypothalamic paraventricular nucleus suggest a role for galanin neural circuits at this level in fluoxetine-induced hydro-osmotic impairment.

Effects of fluoxetine administration on neuropeptide y and orexins in obese zucker rat hypothalamus.

OBJECTIVE: The aim of this work was to study the potential involvement of neuropeptide Y (NPY) and orexins in the anorexigenic mechanism of fluoxetine in obese Zucker rats, assessing the effects of chronic fluoxetine treatment on NPY and orexin immunostaining in several hypothalamic regions. RESEARCH METHODS AND PROCEDURES: Male obese Zucker (fa/fa) rats were administered fluoxetine (10 mg/kg intraperitoneally) daily for 2 weeks. The control group was administered 0.9% NaCl solution. Carcass composition was assessed using the official methods of the Association of Official Analytical Chemists. To test the potential thermogenic effect of fluoxetine administration, total body oxygen consumption was measured daily for 60 minutes before fluoxetine or saline injection and for 30 minutes after drug or saline injection. Hypothalamic arcuate and paraventricular nuclei, and the lateral hypothalamic area were immunostained for NPY, orexin A, and orexin B. Commercial kits were used for serum determinations. RESULTS: Chronic fluoxetine administration in obese Zucker rats generated a reduction in body weight gain, food intake, adipocyte size, fat mass, and body protein. A decrease in NPY immunostaining in the paraventricular nucleus, without changes in the arcuate, was observed. However, no changes were observed in the number of neural cells immunostained for orexin A or orexin B in the lateral hypothalamic area. DISCUSSION: Due to the hyperphagic effect of NPY in the paraventricular nucleus, these results suggest that NPY, but not orexins, could be involved in the anorexigenic effect of fluoxetine in obese Zucker rats.