FODMAP Content Like-by-like Comparison in Spanish Gluten-free and Gluten-containing Cereal-based Products.

Gluten-free foods (GF) availability on supermarket shelves is growing and it is expected to continue expanding in the years ahead. These foods have been linked to a lower content of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs), molecules that trigger gastrointestinal symptoms in sensitive persons. In this study, the FODMAP content of 25 cereal-based GF foods in Spain (breakfast cereals, pasta, bread, biscuits, bakery products, and dough and puff pastry) and 25 gluten-containing equivalents (GC) available in the same supermarket were analysed and compared. Lactose, fructose, glucose, sorbitol, mannitol, raffinose, stachyose and fructans were quantified. In a like-by-like analysis, GF foods were found to generally contain fewer FODMAPs than their GC counterparts. The ingredients used in the manufacture of GF cereal-based foods may contribute to this fact. When the individually wrapped size was considered, the proportion of samples classified as high-FODMAPs in GC and GF foods showed a trend towards fewer samples in the GF. However, not all the GF samples were low-FODMAP. Altogether, our findings provide essential information for FODMAP content databases of GF products in Spain.

Application of a Platform for Gluten-Free Diet Evaluation and Dietary Advice: From Theory to Practice.

The present work aimed to analyze, through the GlutenFreeDiet digital platform, the evolution over one year of the nutritional status, dietary profile and symptoms present among celiac people on a gluten-free diet (GFD) while receiving individualized dietary advice. Twenty-seven adults and thirty-one celiac children/adolescents participated in the study. This was then followed up by three visits, at diagnosis, and after 3 and 12 months (vt0, vt3 and vt12). Participants filled out dietary and gastrointestinal symptoms questionnaires. All patients received written personalized dietary advice from dietitians who interpreted data from the platform. Results obtained indicated that participants consumed proteins and lipids in excess and carbohydrates in defect. Low intakes of cereals, fruit and vegetables and high meat intakes were observed. However, gluten-free product (GFP) consumption and that of ultra-processed foods was reduced after 1 year in adults. Symptoms decreased after vt3 but recurred in vt12. Changes in ultra-processed foods and GFP intake, but lack of changes in the rest of the parameters suggested that the platform support was not effective enough. Even though the platform represents a useful tool for monitoring celiac patients and giving dietary advice, modules that require more continuous attention and nutritional education of patients should be provided for interventions to be more effective.

Knowledge Gaps in Gluten-Free Diet Awareness among Patients and Healthcare Professionals: A Call for Enhanced Nutritional Education.

Diet is the only treatment for celiac disease (CeD), and good adherence to a gluten-free diet (GFD) is the only way to ensure complete remission and to prevent complications. Limited education about the disease and a GFD is an attributing factor to inadequate adherence. Thus, our aim was to assess the current knowledge about a GFD and the clinical monitoring of adherence to the diet among CeD people and HCPs. Specific questionnaires were designed and distributed to assess the knowledge of CeD people (Q1 questionnaire) (n = 2437) and to analyze the follow-up of the disease from the perspective of patients (Q2 questionnaire) (n = 1294) and HCPs (Q3 questionnaire) (n = 346). Two-thirds of HCPs specialized in pediatric care, while one-third did so in adult care. In CeD people, general questions regarding food classification and cross-contamination are well understood. When patients have doubts, 51.4% reported using the Internet and social networks. Thus, it is crucial that resources like social media are reliable and provide valuable information. Q3 revealed the lack of time to follow up the diet after diagnosis (48% of HCPs allocate < 15 min), the interest in further training, and the need for a professional specialized in diets within the healthcare system. In conclusion, it is essential to enhance nutritional education to increase awareness of a GFD.

Study Protocol for a Controlled Trial of Nutrition Education Intervention about Celiac Disease in Primary School: ZELIAKIDE Project.

The only treatment for celiac disease (CD) is a strict and lifelong gluten-free diet (GFD), which must be safe and nutritionally balanced. Avoiding gluten brings difficulties with following the diet and can affect the social life of people with CD. The Zeliakide Project is a nutrition education program aimed at increasing the knowledge of the general population about healthy diets, CD and GFD, and, therefore, to improve the social inclusion and quality of life of people with CD. It is a one-month intervention program, two-armed cluster, non-randomised and controlled trial, conducted among 10-12-year-old children. Pre- and post-intervention evaluation and 1 month follow-up will be carried out to assess the effectiveness of the program. It is based on competencies and their respective learning outcomes. The teaching methodology chosen is a STEAM methodology: inquiry-based learning (IBL). A teaching unit has been created to develop the project, which, in the future, will be useful for the self-application of the program. This study will provide a valid and useful tool to achieve changes in the diet at the school level and will help to promote the social inclusion of people with CD. Moreover, it will enforce the STEAM competences of children.

Uncovering the Concerns and Needs of Individuals with Celiac Disease: A Cross-Sectional Study.

The treatment for celiac disease (CD) involves a strict gluten-free diet, which can be challenging and lead to questions for patients. Pinpointing these uncertainties can enable the creation of efficient educational resources. In this study, a questionnaire was specifically designed to gain insights into the knowledge, concerns, and needs of individuals with CD and their supporters. The questionnaire was distributed through the Instagram social network and received adequate responses from 300 participants, 258 (86%) being female and 152 (50.7%) falling in the age range of 25-44 years. The concerns of individuals with celiac disease and celiac supporters were rated on a 1-4 scale, with a mean score of 3.5 indicating significant concern. A total of 255 (85%) of all participants expressed that their principal concern was the social limitations they faced, such as difficulties in eating out and sharing food with others. Every participant evaluated their overall disease knowledge, averaging at 2.92 out of 4, indicating a reasonable level of awareness. When asked if they believed that improving general knowledge about CD in the general population would enhance their quality of life, the vast majority responded affirmatively. This finding underscores the importance of not only educating individuals with CD but also reaching out to the wider population, especially those who have a direct impact on the daily lives of individuals with CD, such as family members, friends, and food service providers.

Gluten-Free Products: Do We Need to Update Our Knowledge?

The gluten-free (GF) food market has been growing exponentially in recent years. However, GF products could contribute to imbalanced diets. The main objective of the present work was to perform a temporal nutritional comparison of GF foods over the last nine years. At the same time, the nutritional compositions of 104 GF products currently marketed in Spain were assessed and compared with their gluten-containing counterparts. Diets including GF products and the equivalent diets with homologous products with gluten were compared as well, the subjects being 25 adult celiac patients. A comparison of GF products (GFPs) in 2013 and 2022 showed nutritional differences in the groups of cookies, breakfast cereals, doughs/puff pastries/pizzas, and breads. The pasta group stands out from the rest due to an important decrease in energy, protein, simple carbohydrates, saturated lipids, dietary fiber, and salt. Comparing GF and gluten-containing homologous products in 2022, the major differences were found in protein and salt. Accordingly, GFPs lead to a diet lower in protein and higher in carbohydrates. Despite improvements in the formulation of GF products in recent years, their macronutrient profile maintains marked variation, and they cannot be considered nutritionally equivalent to their gluten-containing counterparts.

Nutritional Imbalances in Adult Celiac Patients Following a Gluten-Free Diet.

Celiac disease (CD) is a chronic autoimmune disorder of the small intestine, whose only effective treatment is a gluten-free diet (GFD). It is characterized by the atrophy of the intestinal villi that leads to altered nutrient absorption. This study describes the nutritional imbalances which may be found in adults with CD following a GFD. During the first year of treatment, deficiencies will overcome as the intestinal mucosa recovers. Thus, biochemical data will show this progression, together with the decrease in symptoms. In contrast, in the long term, when a strict GFD is followed and mucosal recovery is achieved, analyzing nutrient intake makes more sense. Macronutrient consumption is characterized by its low complex carbohydrate and fiber intakes, and high fat (especially SFA) and sugar intakes. This profile has been related to the consumption of GFP and their nutritional composition, in addition to unbalanced dietary habits. The most notable deficiencies in micronutrients are usually those of iron, calcium and magnesium and vitamin D, E and some of group B. It is necessary to follow up patients with CD and to promote nutritional education among them, since it could help not only to achieve a gluten free but also a balanced diet.

Effect of analytically measured fiber and resistant starch from gluten-free products on the diets of individuals with celiac disease.

OBJECTIVE: The aim of the present work was to assess the content of fiber and resistant starch (RS) in several gluten-free products (GFPs), compare them with their gluten-containing analogs (GCP) analytically and with label data, and measure the contribution of these foodstuffs to the fiber content of a gluten-free diet. METHODS: Total dietary fiber and RS content in a large amount of GFP (n = 55) and their counterparts (n = 55) were measured by analytical techniques based on AOAC methods. Dietary assessment was carried out with a sample of 141 individuals (pediatric and adult patients with celiac disease) submitted to a food frequency questionnaire and a 24-h recall survey (three times on different days). RESULTS: In general terms, GFP and GCP showed similar fiber and RS content, with the exception of breads, which revealed a higher percentage of both in GFPs. This food group was the main contributor to fiber intake in both groups of patients. Even if GFPs were to be blamed for being nutritionally poorer than GCPs, this was not the case for fiber. CONCLUSIONS: The fiber and RS content were not different in the studied samples, except for the bread. It is noteworthy that label information can underestimate fiber consumption among those with celiac disease, and this must be considered for future database revision. Additionally, we demonstrated a significant effect on the fiber intake of children and adults due to GFPs, and especially to bread, a widely consumed basic product.

Hepatomegaly induced by trans-10,cis-12 conjugated linoleic acid in adult hamsters fed an atherogenic diet is not associated with steatosis.

OBJECTIVE: To study the effects of trans-10,cis-12 conjugated linoleic acid (CLA) on liver size and composition, as well as on hepatic lipogenesis and fatty acid oxidation, in adult hamsters. METHODS: Sixteen male Syrian Golden hamsters (8-month-old; initial body weight 167 +/- 5 g) were divided into two groups and fed on atherogenic diets supplemented either with 0.5% linoleic acid or trans-10,cis-12 CLA, for 6 weeks. Liver lipids, fatty acid profile, protein, water and DNA contents were analysed. The activity and expression of several enzymes involved in liver fatty oxidation and lipogenesis were assessed, as was the expression of transcriptional factors controlling these enzymes. RESULTS: The addition of CLA to the diet led to significantly greater liver weight due to hyperplasia. No changes were observed in liver composition. CLA did not modify the expression or the activity of analysed oxidative enzymes. With regard to lipogenic enzymes, an increase in the expression and the activity of acetyl-CoA carboxylase was found. CONCLUSIONS: These results show that the expected body fat-lowering effect of trans-10,cis-12 CLA, observed in young rodents, is not found in adult hamsters. The lack of increase in liver fatty acid oxidation, help to explain why that effect was not found in these animals. Further, the CLA treatment-induced hepatomegaly is a consequence of hyperplasia.

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.

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.

Conjugated linoleic acid isomers: differences in metabolism and biological effects.

The term conjugated linoleic acid (CLA) refers to a mixture of linoleic acid positional and geometric isomers, characterized by having conjugated double bonds, not separated by a methylene group as in linoleic acid. CLA isomers appear as a minor component of the lipid fraction, found mainly in meat and dairy products from cows and sheep. The most abundant isomer is cis-9,trans-11, which represents up to 80% of total CLA in food. These isomers are metabolized in the body through different metabolic pathways, but important differences, that can have physiological consequences, are observed between the two main isomers. The trans-10,cis-12 isomer is more efficiently oxidized than the cis-9,trans-11 isomer, due to the position of its double bounds. Interest in CLA arose in its anticarcinogenic action but there is an increasing amount of specific scientific literature concerning the biological effects and properties of CLA. Numerous biological effects of CLA are due to the separate action of the most studied isomers, cis-9,trans-11 and trans-10,cis-12. It is also likely that some effects are induced and/or enhanced by these isomers acting synergistically. Although the cis-9,trans-11 isomer is mainly responsible for the anticarcinogenic effect, the trans-10,cis-12 isomer reduces body fat and it is referred as the most effective isomer affecting blood lipids. As far as insulin function is concerned, both isomers seem to be responsible for insulin resistance in humans. Finally, with regard to the immune system it is not clear whether individual isomers of CLA could act similarly or differently.

New Software for Gluten-Free Diet Evaluation and Nutritional Education.

Following a gluten-free diet (GFD) is the only treatment for celiac disease. This diet must ensure the absence of gluten but also needs to be nutritionally balanced. Dietitians working in this field cannot properly evaluate energy and nutrient intake of celiac people because dietary programs available on the market do not contain the nutritional composition of gluten-free products (GFP). Here we present a new GFD evaluation software that contains more than 700 gluten-free rendered foodstuffs and their macronutrient composition. Apart from diet evaluation and design, the software represents a tool for nutritional education as well, since it shows diet appropriacy and indicates how to promote balanced self-care. Moreover, anthropometric and biochemical data or symptoms presence and diet adherence can be recorded and evaluated. This open free software, can be downloaded in its app format for mobiles and tablets. Software evaluation indicated its correct functionality and the importance of assessing a GFD with GFP instead of with their gluten-containing analogues. Thus, this software represents an essential e-Health tool, not only for proper GFD evaluation, but also for improving life quality of celiac and gluten sensitive people.

Trans-10, cis-12-conjugated linoleic acid does not increase body fat loss induced by energy restriction.

Very little evidence exists concerning the effects of conjugated linoleic acid (CLA) on body fat reduction induced by energy restriction. Moreover, although an effect of trans-10, cis-12-CLA on lipolysis has been suggested, it has not been consistently shown. The aims of the present study were to determine whether trans-10, cis-12-CLA increases the reduction of body fat induced by energy restriction, and to analyse its effect on lipolysis and adipose tissue lipase expression (hormone-sensitive lipase (HSL) and adipose tissue TAG lipase (ATGL)). Male Syrian Golden hamsters were fed a high-fat diet during 7 weeks in order to make them fatter. Then they were submitted to a mild energy restriction (25 %) without or with supplementation of 0.5 % trans-10, cis-12-CLA for 3 weeks. Basal glycerol release and lipolysis stimulated by several drugs acting at different levels of the lipolytic cascade were measured in epididymal adipose tissue. The expression of HSL and ATGL was assessed by real-time RT-PCR. No differences were found in adipose tissues size between the experimental groups. Medium adipocyte size and total number of adipocytes were similar in both experimental groups. Animals fed the CLA-enriched diet showed similar lipolytic rates as well as HSL and ATGL expressions to the controls. In conclusion, trans-10, cis-12-CLA does not promote adipose tissue lipid mobilisation nor does it heighten body fat reduction induced by energy restriction. Consequently, this CLA isomer does not seem to be a useful tool to be included in body weight-loss strategies followed in obesity treatment.

Brain endocannabinoid system is involved in fluoxetine-induced anorexia.

In order to describe the effects of chronic fluoxetine administration on the brain endocannabinoid system in lean and obese Zucker rats, brain immunostaining for the CB1 and CB1-phosphorylated cannabinoid receptors was carried out. Obese Zucker rats showed significantly increased the numbers of neural cells positively immunostained for the CB1-phosphorylated receptor in the striatum, compared to their lean litter-mates. Chronic fluoxetine administration decreased the number of neural cells immunostained for CB1-phosphorylated receptor in several striatal and hippocampal regions of obese Zucker rats, compared to controls treated with saline. In contrast, no change in CB1-phosphorylated receptor immunostaining was observed in fluoxetine-treated lean rats, with respect to controls. Taken together, these results suggest the involvement of the hippocampal and striatal endocannabinoid receptor system in fluoxetine-induced anorexia in lean and obese Zucker rats.

Celiac Male's Gluten-Free Diet Profile: Comparison to that of the Control Population and Celiac Women.

The aim of the present work was to analyze the body composition and dietary profile of Spanish celiac men and to compare them to control men and celiac women from our previous studies. Forty-two celiac men (31.5 ± 11.9 years) were recruited and anthropometric measurements were taken. Analysis of energy consumption, macro- and micronutrient intake and food frequency consumption was carried out. Celiac men were more overweight and obese than celiac women, but less than the control population, reporting the same energy intake and macronutrient distribution. Most micronutrient deficiencies in celiac men were not directly related to a gluten free diet; these were also observed for the entire population. The least adherence to Dietary Reference Intakes in women was reported for iron, iodine, potassium and selenium, whereas magnesium intake was higher than in men. Among celiac participants (both genders), cereal, vegetable and legume consumption was poor and meat intake was contrastingly excessive. In conclusion, the dietary profile of celiac men is as unbalanced as that of control men but slightly more than that of celiac women. General nutritional education should be given to both general and celiac populations, and specific advices to celiac men, in order to decrease the risk of celiac disease-related pathologies.

Evolution of Gluten Content in Cereal-Based Gluten-Free Products: An Overview from 1998 to 2016.

The treatment of Celiac disease consists in a strict lifelong gluten-free (GF) diet. As the ingestion of small amounts can have damaging complications, there has been an ongoing discussion regarding the safe threshold for dietary residual gluten. The aim was to analyze the evolution of gluten content in cereal-based GF foodstuffs (n = 3141) from 1998 to 2016 measured by the enzyme-linked immunosorbent assay (ELISA) technique. Eight categories were defined: flours, breakfast cereals/bars, bakery, pasta, breads, dough, snacks, and yeasts, and these were divided into GF labeled-foods (GF-L) or reportedly GF foodstuffs, but not certified (GF-NC). Gluten-detection was decreased over time in line with the evolving European regulations about food information and gluten content claims. This decline started sooner in GF-L products than in GF-NC. As a whole, gluten was detected in 371 samples, with breakfast cereals/bars being the most contaminated group. Snacks and yeasts changed from being high gluten-detected samples to being totally GF over the years. The downside is that, of contaminated samples, those in the low levels of gluten detection range have decreased while flour samples containing over 100 mg/kg gluten have risen in the 2013-2016 period. Obtained data confirm that GF cereal-based foods are becoming safer but gluten control must be maintained.

trans-10,cis-12 conjugated linoleic acid prevents adiposity but not insulin resistance induced by an atherogenic diet in hamsters.

While conjugated linoleic acid (CLA) has received a great deal of attention as a supplement that can favourably modify body composition, its potential impact on insulin sensitivity has not received equal attention. The aim of the present work was to analyse the effects of trans-10,cis-12 CLA isomer on insulin sensitivity in hamsters fed an atherogenic diet. Hamsters were divided into three groups: one group was fed a chow diet (control) and the other two a semipurified atherogenic diet supplemented with 0.5% linoleic acid (LA) or trans-10,cis-12 CLA, respectively. Serum glucose, FFAs, insulin, leptin and adiponectin were measured using commercial kits. HOMA-IR was calculated using the formula of Matthews et al. PPARgamma mRNA was assessed in epididymal adipose tissue by reverse transcription-polymerase chain reaction (RT-PCR). After 6 weeks, atherogenic feeding produced an increase in body fat accumulation as compared with control feeding. The addition of trans-10,cis-12 CLA to the atherogenic diet avoided this feature. Atherogenic feeding also led to significantly higher serum concentrations of glucose, insulin, FFAs, as well as greater HOMA-IR values. trans-10,cis-12 CLA did not prevent these effects. No significant differences were found among experimental groups in serum leptin and adiponectin concentrations, nor in PPARgamma expression. In summary, although the addition of trans-10,cis-12 CLA to an atherogenic diet reduces fat accumulation, it does not improve the impairment of insulin action associated with this feeding. The maintenance of insulin resistance in hamsters fed the atherogenic CLA-enriched diet is probably due to the high serum FFA concentration observed in these animals.

Effects of conjugated linoleic acid on liver composition and fatty acid oxidation are isomer-dependent in hamster.

OBJECTIVE: The present work was designed to study the effects of the two main isomers of conjugated linoleic acid (CLA), cis-9,trans-11 and trans-10,cis-12, on liver composition and hepatic fatty acid oxidation in hamsters. METHODS: Animals were divided into three groups that were fed atherogenic diets supplemented with 0.5% linoleic acid, cis-9,trans-11 CLA, or trans-10,cis-12 CLA for 6 wk. Liver lipids, protein, water and DNA contents, and histologic structure were analyzed. Hepatic carnitine palmitoyltransferase-I and acyl coenzyme A oxidase activities were assessed. Triacylglycerol concentration, and aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, and alkaline phosphatase activities were evaluated in serum. CLA isomer contents were analyzed by gas chromatography in hepatic triacylglycerols. Peroxisome proliferator-activated receptor-alpha mRNA was determined by reverse transcriptase polymerase chain reaction. RESULTS: Trans-10,cis-12 CLA led to significantly greater weight, lower levels of triacylglycerol, cholesterol, and phospholipid, and larger total cell number in liver. Carnitine palmitoyltransferase-I and acyl coenzyme A oxidase activities were significantly increased by this isomer. No changes were induced by cis-9,trans-11 CLA. Trans-10,cis-12 CLA was recovered in significantly lower proportions than cis-9,trans-11 in liver triacylglycerols. Histopathologic analysis showed no abnormalities. No significant differences in serum aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, and alkaline phosphatase activities or in hepatic mRNA peroxisome proliferator-activated receptor-alpha expression were found among the three experimental groups. CONCLUSIONS: These results suggest that the addition of 0.5% of these CLA isomers to the diet do not induce toxic effects in liver after 6 wk of feeding. Intake of trans-10,cis-12 isomer but not of cis-9,trans-11 CLA increases liver fatty acid oxidation. This effect leads to decreased hepatic and serum triacylglycerols.

Doses of Quercetin in the Range of Serum Concentrations Exert Delipidating Effects in 3T3-L1 Preadipocytes by Acting on Different Stages of Adipogenesis, but Not in Mature Adipocytes.

SCOPE: To determine whether doses of quercetin in the range of serum concentrations exert any effect on triacylglycerol accumulation in maturing preadipocytes and mature adipocytes. The influence on the expression of adipogenic markers as well as on gene expression and activity of enzymes involved in triacylglycerol metabolism were assessed. METHODS AND RESULTS: 3T3-L1 preadipocytes were treated during differentiation and mature adipocytes for 24 hours with low doses (0.1-10 µM) of quercetin. Triacylglycerol content in both cell types and free fatty acid and glycerol in the incubation medium of mature adipocytes were measured spectrophotometrically. Gene and protein expression were assessed by RT-PCR and Western blot. LPL and FAS activities were quantified. During differentiation quercetin reduced triacylglycerol content at doses from 0.5 to 10 µM. 1 µM of quercetin reduced C/EBPß gene expression, SREBP1 mature protein levels, and PPARγ gene expression. 10 µM of quercetin reduced LPL gene expression and PPARγ and SREBP1c expression. In mature adipocytes, only 10 µM of quercetin reduced triacylglycerol content. Lipogenic FAS expression and activity were reduced at this dose. CONCLUSION: Quercetin, in the range of serum concentrations, is able to inhibit adipogenesis, but higher doses, at least 10 µM, are needed to reduce fat accumulation in mature adipocytes.