Antioxidants may stop fat cells formation, says study

12/11/2007 - Natural antioxidant compounds like flavonoids and phenolic acids could inhibit the formation of fat formation from fat cells, suggests new research from Taiwan.A study of 15 phenolic acids and six flavonoids were studied for their ability to affect fat cells in laboratory cultures of mouse cells, with o-coumaric acid and rutin reported to inhibit activity of the glycerol-3-phosphate dehydrogenase (GPDH) enzyme that forms triglycerides - fatty materials which at high levels increase the risk of heart disease."These results indicate that flavonoids and phenolic acids may play a role in the control of adipogenesis and they might have further implication in in vivo anti-obesity effects," wrote Chin-Lin Hsu and Gow-Chin Yen from National Chung Hsing University.According to the International Obesity Task Force, an estimated 300 million adults worldwide are obese (body mass index over 30).Moreover, rising obesity is predicted to have a huge impact on public health services. A recent Foresight report predicted that the cost of the epidemic in Britain, in terms of health care provision and lost working hours, could reach £45bn a year by 2050.The new study, published in the Journal of Agricultural and Food Chemistry, looked at the effects of the flavonoids and phenolics on levels of triglyceride in the cells and GPDH activity in 3T3-L1 adipocytes (fat cells). The researchers chose the 3T3-L1 cell line because it has been used widely for several decades as a cell model for fat cell biology research.Among the 15 phenolic acids and six flavonoids tested o-coumaric acid and rutin were found to inhibit intracellular triglyceride the most, by 61 and 83 per cent, respectively.Moreover, the same two compounds were found to be the most potent inhibitors of GPDH, reducing activity by 54 and 67 per cent, respectively.These two compounds also inhibited the expression of peroxisome proliferators-activated receptor gamma (PPAR-gamma), a protein that plays a role in metabolic functions, and the hormone leptin.The compounds also up-regulated expression of adiponectin, a hormone that modulates a number of metabolic processes."Adipose tissue is now known to produce and secrete a PPAR-gamma, which [has a role] in the early stage of adipocyte differentiation," wrote the researchers. "Some studies have addressed the important role that PPAR-gamma plays in the regulation of insulin sensitivity and glucose homeostasis." "The present experiment indicated that o-coumaric acid and rutin treatment inhibited the expression of PPAR-gamma protein levels, which demonstrated that compounds inhibited adipogenesis by affecting the transcriptional factor cascade upstream of PPAR-gamma expression.

Long-term beta-carotene may slow mental decline

13/11/2007 - Men taking beta-carotene supplements for 15 years or more may experience a slower rate of age-related cognitive decline, according to a new study from Harvard.The study highlights the benefits of long-term nutritional support, noting that no short-term benefits were observed in the 1,904 men taking the supplements for less than ten years. "In this generally healthy population, the extent of protection conferred by long-term treatment appeared modest; nonetheless, studies have established that very modest differences in cognition, especially verbal memory, predict substantial differences in eventual risk of dementia; thus, the public health impact of long-term beta carotene use could be large," wrote the authors in the Archives of Internal Medicine.However, in an accompanying editorial in the same journal, Kristine Yaffe from the University of California, San Francisco cautioned that some issues were to be found in interpretation of the data since the study "had a complex design". Francine Grodstein and co-workers from Brigham and Women's Hospital and Harvard Medical School, Boston, tested the cognitive function of participants in the Physicians' Health Study II (PHSII), a continuation of the Physicians' Health Study (PHS) trial looking at the effects of beta carotene and other vitamin supplements on chronic disease, versus placebo.The subjects included participants from the original PHS (started in 1982) and newer recruits from 1998. Beta-carotene supplementation was 50 mg on alternate days.The researchers tested the general cognition, verbal memory, and category fluency of 5956 participants, including 4052 participants from the PHS with a minimum supplementation period of 18 years.The long-term beta-carotene supplementation was associated with a significantly higher mean global score, compared to placebo. This group also performed significantly better than placebo for verbal memory.On the other hand, men in the short-term group displayed no differences in cognition regardless of whether they took beta carotene or placebo.The potential mechanism for the protective effects was postulated to be related to the role of vitamin A (beta-carotene is converted to vitamin A in the body) on beta-amyloid protein production. The build-up of plaque from beta-amyloid deposits is associated with an increase in brain cell damage and death from oxidative stress. This is related to a loss of cognitive function and an increased risk of Alzheimer's.The study is the first to look at long-term antioxidant supplementation in relation to a decline in cognitive function that occurs with naturally with age, and that precedes diseases such as Alzheimer's.

Fish for brain health supported by trio of studies

11/14/2007 - Omega-3-rich fish consumption may improve brain function across a broad demographic spectrum, suggest three new studies from around the world.The studies pull together data from New Zealand, the Netherlands, and Norway, and all suggest significant benefits of fish consumption, specifically the omega-3 fatty acid content, and cognitive health.The majority of science for the health benefits of fish and omega-3 consumption has focused on cardiovascular health, but the science for cognitive benefits is growing and almost as compelling as the heart health data.Moreover, the number of studies reporting potential risk reduction of certain cancers, improved development of a baby during pregnancy, joint health, and improved behaviour and mood, are also growing. Published in the November 2007 issue of The American Journal of Clinical Nutrition, the studies have been commended by an independent expert."These recent reports are novel in that they address the association of n-3 fatty acid intake and cognitive function in non-demented individuals and, thus, present a shift in the attention to earlier stages of cognitive decline with the hope of preventing progression to states of dementia and disability before they become irreversible," wrote Irwin Rosenberg from Tufts University.For the first study, Dutch researchers, led by Carla Dullemeijer from Wageningen University, used data from the FACIT trial, involving 807 men and women (average age 60 at baseline) assigned to receive folic acid or placebo capsules for three years. A cross-sectional analysis studied all 807 participants, while a longitudinal analysis only focused on the 404 participants in the placebo group.The researchers report that increased levels of omega-3 fatty acids in the plasma were associated with a 69 per cent lower decline in sensorimotor speed and a 60 per cent lower decline in complex speed over three years. No effects were observed on memory, the speed at which the participants processed information, or their word fluency. "In this population, plasma n_3 PUFA proportions were associated with less decline in the speed-related cognitive domains over 3 y. These results need to be confirmed in randomized controlled trials," concluded Dullemeijer and co-workers.Researchers in New Zealand investigated if a relationship existed between the fatty acid composition of serum lipids and the mental and physical well-being of 2416 people participating in the 1997 National Nutrition Survey. Using data from a short-form 36 health questionnaire and blood samples, lead author Francesca Crowe from the University of Otago reports that the proportion of EPA in the blood, and the ratio of EPA to arachidonic acid (AA) was positively associated with physical well-being, and the EPA to AA ratio for mental well-being.

Nano-emulsions boost curcumin as health ingredient

11/21/2007 - The health benefits of curcumin, the natural pigment that gives the spice turmeric its yellow colour, could be enhanced by encapsulation in nano-emulsions, suggests new research.The study, published in the journal Food Chemistry, taps into the potential of nano-encapsulation to achieve much-needed differentiation and enhanced product value. Encapsulation, be it on the micro- or nano-scale, is increasingly being used to delay the release of flavours, aromas and bioactive ingredients.The new research looked at the potential of high-speed and high-pressure mixing of oil in water emulsions to protect curcumin and thereby enhance its potential health benefits.Curcumin has increasingly come under the scientific spotlight in recent years, with studies investigating its potential benefits for reducing cholesterol levels, improving cardiovascular health and cancer-fighting abilities.By preparing a model emulsion using medium chain triacylglycerols (MCT) as oil and Tween 20 as emulsifier, researchers from Rutgers University prepared emulsions containing droplets ranging from 618.6 nm to 79.5 nm.According to background information in the article, the majority of ingested curcumin is excreted with only limited uptake into the blood. This is due to the insolubility in water under acidic or neutral conditions. Moreover, the pigment is rapidly metabolised in the intestine, so finding a means to protect curcumin could enhance its bioavailability."Although curcumin is almost insoluble in water, it is found that one per cent curcumin can be successfully encapsulated in O/W emulsions, suggesting that O/W emulsions have a high capacity to carry curcumin," wrote the researchers.When tested in vivo in mice, the researchers reported that inflammation in the ear of the test animals (mice) would be reduced by 43 and 85 per cent when one per cent curcumin was encapsulated in 618.6 nm and 79.5 nm oil-in-water emulsions."It should be pointed out here that it is the synergistic effects of both emulsion droplet size and the presence of lipid in the emulsion that provide the optimum anti-inflammation activity of curcumin," wrote the researchers."Accordingly, high-pressure homogenised curcumin emulsions containing 79.5 nm emulsion droplets exhibit higher anti-inflammation activity than high-speed homogenised curcumin emulsions containing 618.6 nm emulsion droplets," they concluded.The researchers confirmed that the area was one of ongoing study. They state that evaluation of pharmacokinetics and biodistribution of curcumin encapsulated in the emulsions are underway. According to organisers of the recent Nano and Microtechnologies in the Food & Healthfood Industries conference in Amsterdam, the application of nanotechnology and nanoparticles in food are emerging rapidly.