Maternal protein intake during pregnancy is associated with child growth up to 5 years of age, but not through insulin-like growth factor-1: findings from the ROLO study.

Infant protein intake has been associated with child growth, however, research on maternal protein intake during pregnancy is limited. Insulin-like growth factors (IGF) play a role in early fetal development and maternal protein intake may influence child body composition via IGF-1. The aim of this study was to investigate the association of maternal protein intake throughout pregnancy on cord blood IGF-1 and child body composition from birth to 5 years of age. Analysis was carried out on 570 mother-child dyads from the Randomised cOntrol trial of LOw glycaemic index diet study. Protein intake was recorded using 3-d food diaries in each trimester of pregnancy and protein intake per kg of maternal weight (g/d per kg) was calculated. Cord blood IGF-1 was measured at birth. Infant anthropometry was measured at birth, 6 months, 2 and 5 years of age. Mixed modelling, linear regression, and mediation analysis were carried out. Birth weight centiles were positively associated with early-pregnancy protein intake (g/d per kg), while weight centiles from 6 months to 5 years were negatively associated (B=-21·6, P<0·05). These associations were not mediated by IGF-1. Our findings suggest that high protein intake in early-pregnancy may exert an in utero effect on offspring body composition with a higher weight initially at birth but slower growth rates into childhood. Further research is needed to elucidate the exact mechanisms by which dietary protein modulates fetal growth.

Maternal and fetal blood lipid concentrations during pregnancy differ by maternal body mass index: findings from the ROLO study.

BACKGROUND: Pregnancy is a time of altered metabolic functioning and maternal blood lipid profiles change to accommodate the developing fetus. While these changes are physiologically necessary, blood lipids concentrations have been associated with adverse pregnancy outcomes such as gestational diabetes, pregnancy-induced hypertension and high birth weight. As blood lipids are not routinely measured during pregnancy, there is limited information on what is considered normal during pregnancy and in fetal blood. METHODS: Data from 327 mother-child pairs from the ROLO longitudinal birth cohort study were analysed. Fasting total cholesterol and triglycerides were measured in early and late pregnancy and fetal cord blood. Intervals were calculated using the 2.5th, 50th and 97.5th centile. Data was stratified based on maternal body mass index (BMI) measured during early pregnancy. Differences in blood lipids between BMI categories were explored using ANOVA and infant outcomes of macrosomia and large-for-gestational-age (LGA) were explored using independent student T-tests and binary logistic regression. RESULTS: All maternal blood lipid concentrations increased significantly from early to late pregnancy. In early pregnancy, women with a BMI < 25 kg/m2 had lower concentrations of total cholesterol compared to women with a BMI of 25-29.9 kg/m2 (P = 0.02). With triglycerides, women in the obese category (BMI > 30 kg/m2) had higher concentrations than both women in the normal-weight and overweight category in early and late pregnancy (P < 0.001 and P = 0.03, respectively). In late pregnancy, triglyceride concentrations remained elevated in women in the obese category compared to women in the normal-weight category (P = 0.01). Triglyceride concentrations were also elevated in late pregnancy in mothers that then gave birth to infants with macrosomia and LGA (P = 0.01 and P = 0.03, respectively). CONCLUSION: Blood lipid concentrations increase during pregnancy and differ by maternal BMI. These intervals could help to inform the development of references for blood lipid concentrations during pregnancy. TRIAL REGISTRATION: ROLO Study - ISRCTN54392969 . Date of registration: 22/04/2009.

Lower education predicts poor response to dietary intervention in pregnancy, regardless of neighbourhood affluence: secondary analysis from the ROLO randomised control trial.

OBJECTIVE: To determine if response to a low glycaemic index (GI) dietary intervention, measured by changes in dietary intake and gestational weight gain, differed across women of varying socio-economic status (SES). DESIGN: Secondary data analysis of the ROLO randomised control trial. The intervention consisted of a two-hour low-GI dietary education session in early pregnancy. Change in GI was measured using 3 d food diaries pre- and post-intervention. Gestational weight gain was categorised as per the 2009 Institute of Medicine guidelines. SES was measured using education and neighbourhood deprivation. SETTING: The National Maternity Hospital, Dublin, Ireland. SUBJECTS: Women (n 625) recruited to the ROLO randomised control trial. RESULTS: The intervention significantly reduced GI and excess gestational weight gain (EGWG) among women with third level education residing in both disadvantaged (GI, mean (sd), intervention v. control: -3·30 (5·15) v. -0·32 (4·22), P=0·024; EGWG, n (%), intervention v. control: 7 (33·6) v. 22 (67·9); P=0·022) and advantaged areas (GI: -1·13 (3·88) v. 0·06 (3·75), P=0·020; EGWG: 41 (34·1) v. 58 (52·6); P=0·006). Neither GI nor gestational weight gain differed between the intervention and control group among women with less than third level education, regardless of neighbourhood deprivation. CONCLUSIONS: A single dietary education session was not effective in reducing GI or gestational weight gain among less educated women. Multifaceted, appropriate and practical approaches are required in pregnancy interventions to improve pregnancy outcomes for less educated women.

The association between childcare and risk of childhood overweight and obesity in children aged 5 years and under: a systematic review.

UNLABELLED: The aim of this paper was to systematically review the published evidence on the relationship between the type of childcare and risk of childhood overweight or obesity. The databases PubMed, MEDLINE, Cochrane Library and EMBASE were searched using combinations of the various search terms to identify eligible observational studies published between 2000 and May 2016 in English. Fifteen publications from 7 countries matched the inclusion criteria. The most commonly reported childcare arrangements were centre-based (e.g. crèche) and informal care (e.g. relatives, neighbours, friends). Informal care was most frequently associated with an increased risk of childhood overweight and obesity. Associations were also found for other lifestyle variables such as low maternal education, high birth-weight, maternal employment, ethnicity, maternal overweight/obesity and father's Body Mass Index (BMI). CONCLUSION: The relationship between childcare and childhood overweight/obesity is multi-faceted with many aspects linked to childhood adiposity, in particular the age of initiation to care, type of care (i.e. informal care) and shorter breastfeeding duration were related with infant adiposity. WHAT IS KNOWN: • Lifestyle factors during early years affect health outcomes in adulthood, particularly in children with low birth weight. • Pre-school stage influences children's body composition and growth. What is new: • This is the first systematic review of observational studies examining the association between childcare and childhood overweight and obesity in preschool children. • 'Informal' care is linked to early introduction to solid foods, less physical activity and obesity.

The Promotion of Sustainable Diets in the Healthcare System and Implications for Health Professionals: A Scoping Review.

The impacts of the current global food system are already visible in the environment and in the health of the population. The promotion of sustainable diets is key to counter the negative consequences. The healthcare system could be a powerful tool to educate patients by guiding their diets towards sustainability. This study aimed to assess the size and scope of the available literature regarding the promotion of sustainable diets in the healthcare system and to obtain a reliable approximation of the processes and roles related to sustainable diet promotion within healthcare systems. A scoping review where online databases were used to identify English written scientific and grey literature published between 2000-2019 was carried out. The analytical-synthetic approach was used for data charting. Twelve studies were included that were published between 2007-2020. The data highlight education, community and clinical health services, community engagement and policy advocacy, and governance as main action areas along with two transversal aspects, social support, and gender. A systemic approach to the food system is emphasized. Evidence suggests that health professionals have the potential to drive a paradigm shift in food-health environments. Currently, however, their role and potential impact is underestimated within healthcare systems. This review has identified a framework with key areas where processes need to be developed to guarantee sustainable diet promotion in healthcare services.

Association between vitamin D status in early pregnancy and atopy in offspring in a vitamin D deplete cohort.

BACKGROUND: Vitamin D status may play a role in the development of atopic diseases due to its action on lung development and immune system development and function. AIMS: Our objective was to assess whether 25-hydroxyvitamin D (25OHD) levels in maternal blood in pregnancy were associated with atopy in children. METHODS: We analysed 279 mother-child pairs from the ROLO study conducted in Dublin, Ireland. Serum 25OHD was measured at 13 and 28 weeks of pregnancy. Development of childhood atopy was self-reported by mothers at follow-up appointments at 6 months, 2 years or 5 years. Logistic regression analysis was used to evaluate associations between maternal 25OHD status and development of atopy. RESULTS: The mean (SD) 25OHD levels in early and late pregnancy were 41.9 (19.2) nmol/L and 40.2 (21.6) nmol/L, respectively. Maternal 25OHD status in early pregnancy, but not in late pregnancy, was associated with a reduced risk of atopy at 2 years (OR 0.972, CI 0.946-0.999). In early pregnancy, those with serum 25OHD levels < 30 nmol/L compared with those with 25OHD > 50 nmol/L had significantly greater risk of developing atopy at 2 years (OR 4.76, CI 1.38-16.47). CONCLUSIONS: The development of childhood atopy may be associated with maternal vitamin D deficiency in early pregnancy among a cohort of women at risk of vitamin D deficiency. Further research is required to explore the relationship between vitamin D and atopy, particularly among women with poor vitamin D status, and whether supplementation should be prioritised in early pregnancy to reduce childhood atopy.

Antenatal breastfeeding self-efficacy and breastfeeding outcomes among mothers participating in a feasibility breastfeeding-support intervention.

BACKGROUND: Breastfeeding rates in Ireland are among the lowest worldwide. A feasibility study of a breastfeeding-support intervention explored maternal characteristics associated with antenatal breastfeeding self-efficacy and with infant-feeding mode at 6 weeks postpartum among women giving birth in Ireland. METHODS: We conducted a prospective study across two sites, urban and rural: The National Maternity Hospital (NMH), Dublin and Wexford General Hospital (WGH), Wexford. Nulliparous, pregnant women were recruited at approximately 32 weeks gestation from the hospitals' antenatal out-patient departments. Participants attended an antenatal class with a support partner, received a one-to-one session with a lactation consultant after delivery and had access to a breastfeeding-support clinic and telephone advice postpartum. Our aim was to understand maternal variables associated with breastfeeding self-efficacy and infant-feeding mode. We explored associations between continuous and categorical variables and any breastfeeding and exclusive breastfeeding using t tests and Chi-squared analyses. RESULTS: One hundred mothers provided baseline data; 64 provided follow-up data. Lower maternal age and non-Irish nationality were associated with higher antenatal breastfeeding self-efficacy. At the rural unit, mothers with tertiary education were more likely to be exclusively breastfeeding than those with secondary education. Though not statistically significant, more normal-weight mothers from the urban unit were exclusively breastfeeding at 6 weeks than overweight/obese mothers. CONCLUSIONS: Breastfeeding outcomes differed by maternal education. Future interventions should target mothers with lower education and possibly also overweight and obese mothers. Increasing breastfeeding self-efficacy, particularly among older and Irish-born mothers, may be a mechanism for improving breastfeeding outcomes.

Impact of maternal education on response to lifestyle interventions to reduce gestational weight gain: individual participant data meta-analysis.

OBJECTIVES: To identify if maternal educational attainment is a prognostic factor for gestational weight gain (GWG), and to determine the differential effects of lifestyle interventions (diet based, physical activity based or mixed approach) on GWG, stratified by educational attainment. DESIGN: Individual participant data meta-analysis using the previously established International Weight Management in Pregnancy (i-WIP) Collaborative Group database (https://iwipgroup.wixsite.com/collaboration). Preferred Reporting Items for Systematic reviews and Meta-Analysis of Individual Participant Data Statement guidelines were followed. DATA SOURCES: Major electronic databases, from inception to February 2017. ELIGIBILITY CRITERIA: Randomised controlled trials on diet and physical activity-based interventions in pregnancy. Maternal educational attainment was required for inclusion and was categorised as higher education (≥tertiary) or lower education (≤secondary). RISK OF BIAS: Cochrane risk of bias tool was used. DATA SYNTHESIS: Principle measures of effect were OR and regression coefficient. RESULTS: Of the 36 randomised controlled trials in the i-WIP database, 21 trials and 5183 pregnant women were included. Women with lower educational attainment had an increased risk of excessive (OR 1.182; 95% CI 1.008 to 1.385, p =0.039) and inadequate weight gain (OR 1.284; 95% CI 1.045 to 1.577, p =0.017). Among women with lower education, diet basedinterventions reduced risk of excessive weight gain (OR 0.515; 95% CI 0.339 to 0.785, p = 0.002) and inadequate weight gain (OR 0.504; 95% CI 0.288 to 0.884, p=0.017), and reduced kg/week gain (B -0.055; 95% CI -0.098 to -0.012, p=0.012). Mixed interventions reduced risk of excessive weight gain for women with lower education (OR 0.735; 95% CI 0.561 to 0.963, p=0.026). Among women with high education, diet based interventions reduced risk of excessive weight gain (OR 0.609; 95% CI 0.437 to 0.849, p=0.003), and mixed interventions reduced kg/week gain (B -0.053; 95% CI -0.069 to -0.037,p<0.001). Physical activity based interventions did not impact GWG when stratified by education. CONCLUSIONS: Pregnant women with lower education are at an increased risk of excessive and inadequate GWG. Diet based interventions seem the most appropriate choice for these women, and additional support through mixed interventions may also be beneficial.

A Low Glycaemic Index Diet in Pregnancy Induces DNA Methylation Variation in Blood of Newborns: Results from the ROLO Randomised Controlled Trial.

The epigenetic profile of the developing fetus is sensitive to environmental influence. Maternal diet has been shown to influence DNA methylation patterns in offspring, but research in humans is limited. We investigated the impact of a low glycaemic index dietary intervention during pregnancy on offspring DNA methylation patterns using a genome-wide methylation approach. Sixty neonates were selected from the ROLO (Randomised cOntrol trial of LOw glycaemic index diet to prevent macrosomia) study: 30 neonates from the low glycaemic index intervention arm and 30 from the control, whose mothers received no specific dietary advice. DNA methylation was investigated in 771,484 CpG sites in free DNA from cord blood serum. Principal component analysis and linear regression were carried out comparing the intervention and control groups. Gene clustering and pathway analysis were also explored. Widespread variation was identified in the newborns exposed to the dietary intervention, accounting for 11% of the total level of DNA methylation variation within the dataset. No association was found with maternal early-pregnancy body mass index (BMI), infant sex, or birthweight. Pathway analysis identified common influences of the intervention on gene clusters plausibly linked to pathways targeted by the intervention, including cardiac and immune functioning. Analysis in 60 additional samples from the ROLO study failed to replicate the original findings. Using a modest-sized discovery sample, we identified preliminary evidence of differential methylation in progeny of mothers exposed to a dietary intervention during pregnancy.

A feasibility study of a multidimensional breastfeeding-support intervention in Ireland.

BACKGROUND: Breastfeeding is the optimum mode of infant feeding. Despite this, most global populations do not achieve the World Health Organisation's recommendation of exclusive breast milk for the first 6 months of life. Irish breastfeeding rates are among the lowest in Europe, necessitating a well-designed breastfeeding-support intervention. AIM: To evaluate the feasibility and acceptability of a multidimensional breastfeeding intervention in a rural and an urban maternity setting in Ireland. DESIGN: A feasibility study of a breastfeeding-support intervention. SETTING: Participants were recruited from The National Maternity Hospital (Dublin, urban) and Wexford General Hospital (Wexford, rural). Questionnaires were completed antenatally, at 6 weeks postpartum and at 3 months postpartum to assess acceptability of the intervention and determine breastfeeding status. PARTICIPANTS: Pregnant women were recruited in the 3rd trimester, alongside a support partner. INTERVENTION: The intervention consisted of an antenatal class (including the physiology and practical approaches to breastfeeding), a one-to-one breastfeeding consultation with a lactation consultant after birth, access to a breastfeeding helpline, online resources, and a postnatal breastfeeding support group which included a one-to-one consultation with the lactation consultant. RESULTS: One hundred women from The National Maternity Hospital, Dublin and 27 women from Wexford General Hospital were recruited. The antenatal class was attended by 77 women in Dublin and 23 in Wexford; thus, 100 women participated in the intervention. Seventy-six women had a one-to-one postnatal consultation with a lactation consultant in Dublin and 23 in Wexford. Fifty and 45 women in Dublin, and 15 and 15 in Wexford responded to the 6-week and 3-month questionnaires, respectively. At 3 months postpartum, 70% of respondents from Dublin and 60% from Wexford were breastfeeding. Mothers perceived the one-to-one consultation with the lactation consultant during postnatal hospitalization as the most helpful part of the intervention. Inclusion of a support partner was universally viewed positively as a means to support the mother's decision to initiate and continue breastfeeding. CONCLUSION: This multidimensional intervention is well-accepted and feasible to carry out within an Irish cohort, in both urban and rural areas. Data from this feasibility study will be used to design a randomized controlled trial of a breastfeeding-support intervention.

Metabolic programming of a beige adipocyte phenotype by genistein.

SCOPE: Promoting the development of brown or beige adipose tissue may protect against obesity and related metabolic features, and potentially underlies protective effects of genistein in mice. METHODS AND RESULTS: We observed that application of genistein to 3T3-L1 adipocytes changed the lipid distribution from large droplets to a multilocular distribution, reduced mRNAs indicative of white adipocytes (ACC, Fasn, Fabp4, HSL, chemerin, and resistin) and increased mRNAs that are a characteristic feature of brown/beige adipocytes (CD-137 and UCP1). Transcripts with a role in adipocyte differentiation (Cebpß, Pgc1α, Sirt1) peaked at different times after application of genistein. These responses were not affected by the estrogen receptor (ER) antagonist fulvestrant, revealing that this action of genistein is not through the classical ER pathway. The Sirt1 inhibitor Ex-527 curtailed the genistein-mediated increase in UCP1 and Cebpß mRNA, revealing a role for Sirt1 in mediating the effect. Baseline oxygen consumption and the proportional contribution of proton leak to maximal respiratory capacity was greater for cells exposed to genistein, demonstrating greater mitochondrial uncoupling. CONCLUSIONS: We conclude that genistein acts directly on adipocytes or on adipocyte progenitor cells to programme the cells metabolically to adopt features of beige adipocytes. Thus, this natural dietary agent may protect against obesity and related metabolic disease.

Child Care Exposure Influences Childhood Adiposity at 2 Years: Analysis from the ROLO Study.

BACKGROUND: The first 2 years of life are instrumental for childhood physical development. Factors contributing to childhood obesity are difficult to determine; child care exposure is one to consider, by influencing food preference and physical activity development. OBJECTIVE: To investigate the association of child care exposure with adiposity at 2 years. METHODS: Data were collected as part of the secondary analysis of the prospective ROLO study (randomized control trial of low glycemic index diet) in Dublin, Ireland. Mothers were recruited antenatally and followed up at 2 years postpartum. Maternal and childhood anthropometric data and lifestyle questionnaires, reporting on child care attendance (defined as nonparental care), exposure (weeks), and infant-feeding practices, were collected. RESULTS: Anthropometric measures and lifestyle data were collected for 273 mothers and children aged 2 years, 52.7% of whom attended child care. Child care was predominately provided by a nonrelative (83.7%), either in a crèche (57%) or by a childminder (26.7%). More than half (56.2%) of the children attended child care part-time (≤30 hours/week). Central adiposity measures (abdominal circumference, waist:height ratio) and total adiposity (sum of all skin folds) were significantly elevated in children with increasing time in child care. Children provided with "meals and snacks" had elevated adiposity measures versus those given "snacks or no food." No difference in the infant-feeding practices was identified between the child care groups. CONCLUSIONS: Children attending child care have higher total and central adiposity, proportional to exposure. More research is required to investigate this link to appropriately design health promotion and obesity prevention programs targeting children at 2 years.

Maternal Blood Lipid Profile during Pregnancy and Associations with Child Adiposity: Findings from the ROLO Study.

BACKGROUND: The in-utero environment affects fetal development; it is vital to understand how maternal diet during pregnancy influences childhood body composition. While research indicates that triglycerides in hyperglycaemic women may increase birth weight, little is known about this relationship in euglycemic women. This study examines the relationship between maternal blood lipid status and infant adiposity up to 2 years of age. METHODS: Data from 331 mother-child pairs from the ROLO longitudinal birth cohort study was analysed. Maternal dietary intakes were recorded and fasting blood lipids, leptin and HOMA were measured in early and late pregnancy and cord blood. Infant anthropometric measurements and skin-fold thicknesses were recorded at birth, 6 months and 2 years. Correlation and regression analyses were used to explore associations between maternal blood lipid status and infant adiposity. RESULTS: All maternal blood lipids increased significantly during pregnancy. Maternal dietary fat intake was positively associated with total cholesterol levels in early pregnancy. Late pregnancy triglycerides were positively associated with birth weight (P = 0.03) while cord blood triglycerides were negatively associated with birth weight (P = 0.01). Cord HDL-C was negatively associated with infant weight at 6 months (P = 0.005). No other maternal blood lipids were associated with infant weight or adiposity up to 2 years of age. CONCLUSION: Maternal and fetal triglycerides were associated with birth weight and cord HDL-C with weight at 6 months. Thus, maternal lipid concentrations may exert in-utero influences on infant body composition. There may be potential to modulate infant body composition through alteration of maternal diet during pregnancy.

Nutrition During Pregnancy Impacts Offspring's Epigenetic Status-Evidence from Human and Animal Studies.

Pregnancy is a vital time of growth and development during which maternal nutrition significantly influences the future health of both mother and baby. During pregnancy, the fetus experiences a critical period of plasticity. Epigenetics, specifically DNA methylation, plays an important role here. As nutrition is influential for DNA methylation, this review aims to determine if maternal nutrition during pregnancy can modify the offspring's epigenome at birth. Research focuses on micronutrients and methyl donors such as folate and B vitamins. Evidence suggests that maternal nutrition does not largely influence global methylation patterns, particularly in nutrient-replete populations; however, an important impact on gene-specific methylation is observed. A link is shown between maternal nutrition and the methylome of the offspring; however, there remains a paucity of research. With the potential to use DNA methylation patterns at birth to predict health of the child in later life, it is vital that further research be carried out.

Resveratrol does not increase body fat loss induced by energy restriction.

Resveratrol (RSV) is known to have an antiobesogenic effect because it mimics energy restriction. However, hardly any evidence exists concerning the combined effects of RSV and energy restriction on body fat reduction. So, the aim of the present study was to determine whether RSV increases body fat reduction induced by energy restriction. Male Wistar rats were fed a high-fat, high-sucrose diet for 6 weeks to obtain a diet-induced obesity model. Then they were submitted to a mild energy restriction (25%) without or with RSV supplementation (30 mg/kg body weight/day) for 2 weeks. Final body weight, subcutaneous and intra-abdominal white adipose tissues weights, Adipose Index, and serum triacylglycerol, cholesterol, glucose, and insulin were assessed. Lipoprotein lipase (LPL), fatty acid synthase (FAS), and acetyl coenzyme A carboxylase (ACC) activities, as well as their genetic expressions, were measured in white adipose tissue. Final body weight, white adipose tissue weights, Adipose Index, and serum triacylglycerol, cholesterol, and insulin were reduced in both groups, but no differences were found among them. FAS, ACC, and LPL activities and expressions were also similar in both groups. These results suggest a lack of any adjuvant effect of RSV on energy restriction for obesity treatment purposes.

Hepatic lipid metabolic pathways modified by resveratrol in rats fed an obesogenic diet.

OBJECTIVE: The scientific community is on the look-out for safe biomolecules useful in the prevention of obesity and related aberrations such as fatty liver. This study analyzed the influence of resveratrol on hepatic triacylglycerol metabolism. METHODS: Male Sprague-Dawley rats were divided into control and resveratrol-treated groups (30 mg/kg of body weight per day) and fed a commercial obesogenic diet for 6 wk. Liver triacylglycerol content and the activity of carnitine palmitoyl transferase-Ia (CPT-Ia), acyl-coenzyme A oxydase (ACO), fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH), malic enzyme (ME), acetyl-coenzyme A carboxylase (ACC), adenosine monophosphate-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) activation were measured. Mitochondrial protein cytochrome C oxidase subunit 2 (COXII), mitochondrial transcription factor A (TFAM), sterol regulatory element-binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor-α (PPAR-α), sirtuin-1 (SIRT1), hepatocyte nuclear factor receptor-4α (HNF-4α), and PGC-1α mRNA levels were also analyzed. Serum insulin was quantified. RESULTS: Resveratrol decreased liver fat accumulation, increased CPT-Ia and ACO, and decreased ACC activities. Other lipogenic enzymes, FAS, ME, and G6PDH were not modified. The polyphenol activated AMPK and PGC-1α. The expression of SRBP-1c, PPAR-α, SIRT1, PGC-1α, HNF-4α, TFAM, and COXII was not modified. No changes in serum insulin levels were observed. CONCLUSION: Resveratrol partly prevents the increase in liver fat accumulation induced by high-fat high-sucrose feeding by increasing fatty acid oxidation and decreasing lipogenesis. These effects are mediated by the activation of the AMPK/SIRT1 axis.

Thermogenesis is involved in the body-fat lowering effects of resveratrol in rats.

The effect of resveratrol on thermogenesis in skeletal muscle and interscapular brown adipose tissue (IBAT) was investigated. Rats were fed an obesogenic diet supplemented with resveratrol (30mg/kg/day) or not supplemented for 6weeks. Resveratrol intake led to increased gene expression of mitochondrial-transcription-factor-A (TFAM), mitochondrial-protein-cytochrome-C-oxidase subunit-2 (COX2), sirtuin-1 (SIRT1), peroxisome-proliferator-activated-receptor-ß/δ (PPARß/δ) and proliferator-activated-receptor-gamma-coactivator1-α (PGC-1α) in IBAT and increased UCP1protein expression; however, peroxisome-proliferator-activated-receptor-α (PPARα) expression remained unchanged. In gastrocnemius muscle, resveratrol increased the gene expression of TFAM and COX2; however, no changes were observed in levels of SIRT1, PGC-1α and PPARß/δ. Acetylated-PGC-1α was decreased in the resveratrol-treated group, indicating a higher level of activation, and a significant increase of UCP3 protein expression was observed in this group. The increases in UCP protein expression in two important thermogenic tissues after resveratrol treatment may contribute to increased whole-body energy dissipation, which may help to better understand the body-fat lowering effect of this polyphenol.

Changes in white adipose tissue metabolism induced by resveratrol in rats.

BACKGROUND: A remarkable range of biological functions have been ascribed to resveratrol. Recently, this polyphenol has been shown to have body fat lowering effects. The aim of the present study was to assess some of the potential underlying mechanisms of action which take place in adipose tissue. METHODS: Sixteen male Sprague-Dawley rats were randomly divided into two groups: control and treated with 30 mg resveratrol/kg body weight/d. All rats were fed an obesogenic diet and after six weeks of treatment white adipose tissues were dissected. Lipoprotein lipase activity was assessed by fluorimetry, acetyl-CoA carboxylase by radiometry, and malic enzyme, glucose-6P-dehydrogenase and fatty acid synthase by spectrophotometry. Gene expression levels of acetyl-CoA carboxylase, fatty acid synthase, lipoprotein lipase, hormone-sensitive lipase, adipose triglyceride lipase, PPAR-gamma, SREBP-1c and perilipin were assessed by Real time RT-PCR. The amount of resveratrol metabolites in adipose tissue was measured by chromatography. RESULTS: There was no difference in the final body weight of the rats; however, adipose tissues were significantly decreased in the resveratrol-treated group. Resveratrol reduced the activity of lipogenic enzymes, as well as that of heparin-releasable lipoprotein lipase. Moreover, a significant reduction was induced by this polyphenol in hormone-sensitive lipase mRNA levels. No significant changes were observed in other genes. Total amount of resveratrol metabolites in adipose tissue was 2.66 ± 0.55 nmol/g tissue. CONCLUSIONS: It can be proposed that the body fat-lowering effect of resveratrol is mediated, at least in part, by a reduction in fatty acid uptake from circulating triacylglycerols and also in de novo lipogenesis.