Omega-6 polyunsaturated fatty acids and the early origins of obesity

PURPOSE OF REVIEW: The incidence of obesity and its related metabolic disorders has increased significantly over the past 3 decades, culminating in the current global epidemic of metabolic disease and leading to the search for contributing factors. Exposure of the developing foetus/neonate to a typical Western diet increases their risk of obesity and metabolic disorders throughout the life-course, creating an intergenerational cycle of metabolic disease. In Western countries, this epidemic of metabolic disease has coincided with a marked increase in the intake of omega-6 polyunsaturated fatty acids (omega-6 PUFA), leading to suggestions that the two may be causally related. RECENT FINDINGS: Recent studies have emphasized the proadipogenic properties of the omega-6 PUFA, and provided evidence that rodents fed on diets with omega-6 PUFA contents similar to the typical US diet (6–8% energy) have an increased fat mass. Importantly, recent studies have shown that perinatal exposure to a high omega-6 PUFA diet results in a progressive accumulation of body fat across generations. SUMMARY: This review highlights the recent evidence supporting the role of the omega-6 PUFA in the early life origins of obesity and metabolic disease, the need for more clinical studies and the potential need for health agencies to re-evaluate current recommendations to further increase omega-6 PUFA intakes.Beverly S. Muhlhausler and Gérard P. Ailhau

Establishment of preadipocyte clonal line from epididymal fat pad of ob/ob mouse that responds to insulin and to lipolytic hormones

A clonal cell line that responds to insulin and to lipolytic hormones has been established from the epididymal fat pad of the C57BL/6J ob/ob mouse. This line, designated ob 17, has a doubling time of 12.5 or 19 hr in 10% or 1% fetal calf serum, respectively. It presents a heterogeneous chromosome number with 40% of the cells containing 35-44 chromosomes and expresses the characteristic H2-LA antigen. After cessation of growth, ob 17 cells accumulate droplets of triglycerides; this accumulation occurs to a significant extent even in the absence of insulin normally added after confluence. Lipoprotein lipase activity is negligible in exponentially growing cells but appears at its maximal level just after confluence with or without insulin. Acid:CoA ligase and acylCoA:diglyceride acyltransferase develop later than lipoprotein lipase. The appearance of lipolytic and lipogenic enzymes, but not of triglycerides, seems to be independent of the presence of lipoproteins or of unesterified fatty acids in the culture medium. Therefore, the differentiation program becomes operative when growth is arrested, and differentiation occurs, providing a source of exogenous lipids. Differentiated ob 17 cells in which endogenous triglycerides have been prelabeled on the fatty acid moiety do respond to epinephrine and corticotropin by release of radioactive fatty acid. This lipolytic response is counteracted by prior addition of insulin. The ob 17 cell line appears to be a useful model for study of growth and differentiation of adipose cells as compared to preadipocyte cell lines from the nongenetically obese mouse

Quintais agroecológicos conquistam o Semiárido brasileiro: Segurança alimentar para os mais vulneráveis com o uso da força da terra

Quintais representam um espaço para prosa, troca de mudas e descanso; o projeto acrescentou a estes fatores a utilização de princípios agroecológicos. O resultado é um sistema que possibilita a produção de alimentos saudáveis a partir de processos produtivos coerentes com os recursos naturais disponíveis

The effectiveness of ω-3 polyunsaturated fatty acid interventions during pregnancy on obesity measures in the offspring: an up-to-date systematic review and meta-analysis.

BACKGROUND: The potential role of ω-3 long chain polyunsaturated fatty acid (LCPUFA) supplementation during pregnancy on subsequent risk of obesity outcomes in the offspring is not clear and there is a need to synthesise this evidence. OBJECTIVE: A systematic review and meta-analysis of randomised controlled trials (RCTs), including the most recent studies, was conducted to assess the effectiveness of ω-3 LCPUFA interventions during pregnancy on obesity measures, e.g. BMI, body weight, fat mass in offspring. METHODS: Included RCTs had a minimum of 1-month follow-up post-partum. The search included CENTRAL, MEDLINE, SCOPUS, WHO's International Clinical Trials Reg., E-theses and Web of Science databases. Study quality was evaluated using the Cochrane Collaboration's risk of bias tool. RESULTS: Eleven RCTs, from ten unique trials, (3644 children) examined the effectiveness of ω-3 LCPUFA maternal supplementation during pregnancy on the development of obesity outcomes in offspring. There were heterogeneities between the trials in terms of their sample, type and duration of intervention and follow-up. Pooled estimates did not show an association between prenatal intake of fatty acids and obesity measures in offspring. CONCLUSION: These results indicate that maternal supplementation with ω-3 LCPUFA during pregnancy does not have a beneficial effect on obesity risk. Due to the high heterogeneity between studies along with small sample sizes and high rates of attrition, the effects of ω-3 LCPUFA supplementation during pregnancy for prevention of childhood obesity in the long-term remains unclear. Large high-quality RCTs are needed that are designed specifically to examine the effect of prenatal intake of fatty acids for prevention of childhood obesity. There is also a need to determine specific sub-groups in the population that might get a greater benefit and whether different ω-3 LCPUFA, i.e. eicosapentaenoic (EPA) vs. docosahexanoic (DHA) acids might potentially have different effects