Consumption of omega 3 fatty acids is known to have health benefits. For many years, the importance of the only member of the omega 3 family considered to be essential, alpha-linolenic acid (ALA), has been overlooked. Current research indicates that ALA, along with its longer chain metabolites, may play an important role in many physiological functions. Potential benefits of ALA include cardioprotective effects, modulation of the inflammatory response, and a positive impact on both central nervous system function and behavior. Recommended levels for ALA intake have been set, yet the possible advantages of its consumption are just being revealed.

BARNEA, MAAYAN, AVI SHAMAY, ALIZA H. STARK, AND ZECHARIA MADAR. A high-fat diet has a tissue-specific effect on adiponectin and related enzyme expression. Obesity. 2006;14:2145-2153. Objective: This study was designed to test whether adiponectin plays a role in diet-induced obesity and insulin resistance and acts as a mediator to induce or inhibit specific metabolic pathways involved in lipid metabolism Research Methods and Procedures: Forty C57BL/6J male mice were fed either a high-fat (HF) or control diet for 4 months, and adiponectin, its receptors, and enzyme expression in liver and muscle tissue were measured. Results: Mice fed the HF diet exhibited significantly greater weight gain, abnormal oral glucose tolerance test curves, and elevated homeostasis model assessment of insulin resistance (5.3 Ϯ 0.89 vs. 2.8 Ϯ 0.39). A significant reduction of adiponectin RNA expression (51%) and protein levels (15%) was observed in the adipose tissue of HF animals; however, serum adiponectin levels did not differ between groups (7.12 Ϯ 0.34 g/mL vs. 6.44 Ϯ 0.38 g/mL). Expression of hepatic mRNA of AdipoR1 and AdipoR2 was reduced by 15% and 25%, respectively, in animals fed the HF diet. In contrast, receptor mRNA expression of AdipoR1 and AdipoR2 increased by 25% and 30%, respectively, in muscle tissue. No effect was found on hepatic adenosine monophosphate-activated protein kinase expression; however, a significant reduction of phosphoadenosine monophosphate kinase levels in muscles was observed. Hepatic acetyl-coenzyme A carboxylase was similar between groups, but in muscles, the inactive form phosphoacetylcoenzyme A carboxylase was significantly reduced (p Ͻ 0.05). Discussion: The HF diet led to decreased insulin sensitivity accompanied by impaired activity of adiponectin-related enzymes in skeletal muscles but not in the liver. These results suggest that the HF diet has a tissue-specific effect on adiponectin and associated enzyme expression.

The present study investigated the effects of the red microalga Porphyridium sp. on gastrointestinal physiology and lipid metabolism in male Sprague-Dawley rats. Diets containing dietary fibre from pelleted red microalgal cells (biomass) or their sulfated polysaccharide, pectin or cellulose (control) were fed to rats for a period of 30 d. All three fibre-supplemented diets increased the length of both the small intestine and colon, with a significantly greater effect in rats fed the algal polysaccharide. The polysaccharide also increased mucosa and muscularis cross-sectional area of the jejunum, and caused hypertrophy in the muscularis layer. The algal biomass significantly lowered gastrointestinal transit time by 44 % in comparison with the control rats. Serum and mucosal cholecystokinin levels were lower in rats on the pectin and polysaccharide diets, while cholecystokinin levels in rats fed algal biomass were not different from those in the control animals. In comparison with the control diet, all the experimental diets significantly lowered serum cholesterol levels (22–29 %). Feeding of non-fermentable algal polysaccharide or biomass significantly increased faecal weight and bile acid excretion compared with pectin-fed or control rats. The algal polysaccharide and biomass were thus shown to be potent hypocholesterolaemic agents active at low concentrations in the diet. Both metabolic and morphological changes were observed following consumption of algae, suggesting several possible mechanisms by which the alga affects lipid metabolism. The results presented in the present study encourage the use of red microalga as a functional food.

Athletes competing in individual sports such as judo are categorized by weight. Before competitions, weight cutting is common. This cross-sectional study was designed to characterize and determine the prevalence of rapid weight loss (RWL) among adolescent judo competitors. Male athletes aged 12- to 17-years old (N = 108) were recruited from local judo teams. Each participant completed a validated questionnaire regarding RWL practices. Anthropometric measurements were also performed. Average age was 14.6 ± 1.6 years and all participants were of normal body mass index (BMI). RWL was practiced by 80% of the athletes before competition, beginning at an average age of 12.5 ± 2.2 years with the highest prevalence (~94%) in the oldest group of judoka (16-17.9 years). Precompetition weight loss duration was 8 ± 5.4 days, with an average weight reduction of 1.5 ± 1.1 kg. The number of weight loss efforts per athlete in the past season was 2.8 ± 2.2. RWL was achieved by increased physical activity (82.6%), skipped meals (56.3%), or fasting at least once (47%). Two-thirds of the athletes indicated that their coaches were the most influential figure in their decision to lose weight before competition. RWL is highly prevalent in adolescent judo competitors. The methods used by these athletes can potentially lead to significant health risks including compromised nutritional status, diminished physical performance and impaired growth and development. It is of great importance to insure that those who guide young adults in weight loss for competitive sports have the knowledge and understanding to make safe recommendations and appropriate decisions regarding achieving specific weight goals.

The hypocholesterolaemic properties of an ethanol extract from defatted fenugreek (Trigonella foenumgraecum) seeds were investigated. Purification of the crude extract by dialysis produced an isolated component with haemolytic properties. The dialysate was also found to contain saponins demonstrated by thin-layer chromatography. Experiments in vitvo employing the everted-sac technique showed that the ethanol extract had the ability to inhibit taurocholate and deoxycholate absorption in a dose-dependent manner. In two separate feeding experiments, hypercholesterolaemic rats were fed on 30 or 50 g ethanol extract/kg for a 4-week period. Reductions in plasma cholesterol levels ranged from 18 to 26% and a tendency for lower concentrations of liver cholesterol was observed. These results indicate that the ethanol extract from fenugreek seeds contained hypocholesterolaemic components which appear to be saponins that interact with bile salts in the digestive tract.