Supplements of omega-3s may slow cellular ageing in older people with mild cognitive impairment, according to results of a pilot randomized clinical trial.
DHA (docosahexaenoic acid) was associated with reduced shortening of telomeres, DNA sequences at the end of chromosomes that shorten as cells replicate and age, report researchers from Australia in the journal Nutrition.
The aging and lifespan of normal cells are linked to the “telomerase shortening mechanism”, which limits cells to a fixed number of divisions. During cell replication, the telomeres function by ensuring the cell’s chromosomes do not fuse with each other or rearrange, which can lead to cancer. Elizabeth Blackburn, a telomere pioneer at the University of California San Francisco, likened telomeres to the ends of shoelaces, without which the lace would unravel.
With each replication the telomeres shorten, and when the telomeres are totally consumed, the cells are destroyed (apoptosis). Previous studies have also reported that telomeres are highly susceptible to oxidative stress. “It is becoming increasingly evident that damage specific to the telomeric ends of chromosomes is one of the most critical events that initiate genome instability leading to accelerated ageing, cognitive decline and neurodegenerative disease,” explained the authors of the new paper.
This is not the first time that omega-3s have been linked to reduced telomere shortening, with findings from a study by researchers from the University of California, San Francisco indicating that high blood levels of omega-3 fatty acids may slow cellular ageing in people with coronary heart disease (JAMA, Vol. 303, pp. 250-257).
The UCSF study was epidemiological, however, while the new study, performed by scientists from the Commonwealth Scientific and Industrial Research Organization (CSIRO), the University of South Australia, and the University of Newcastle is an intervention study, albeit on a pilot scale.
Led by Nathan O’Callaghan, the researchers recruited 33 people over the age of 65 with mild cognitive impairment, and randomly assigned them to one of three groups: The first group received EPA (eicosapentaenoic acid) omega-3 supplements (1.67g EPA+0.16g DHA/day); the second group received DHA omega-3 supplements (1.55g DHA+0.40g EPA/day), or omega-6 linoleic acid (LA, 2.2g/day) for six months.
Results of the study showed that the omega-6 group exhibited the greatest shortening of telomere length, compared to the DHA and EPA groups. Increased levels of DHA in red blood cells was significantly associated with reduced telomere shortening in the DHA group, said O’Callaghan and his co-workers. “Although underpowered to detect significant differences between treatment groups, this study provides interesting pilot data that indicates telomere shortening may be modified by nutritional means over a six month period,” they wrote.
“Specifically, increasing n-3 PUFA intake via supplementation may attenuate telomere shortening that occurs with age. These data build on current epidemiological evidence and recent reports linking increased marine n-3 PUFA with decreased telomere attrition.
Published online ahead of print, doi: 10.1016/j.nut.2013.09.013
“Telomere shortening in elderly people with mild cognitive impairment may be attenuated with omega-3 fatty acid supplementation: A randomized controlled pilot study”
Authors: N. O’Callaghan, N. Parletta, Catherine M. Milte, Bianca Benassi-Evans, Michael Fenech, Peter RC. Howe
Clinical Effects of Diet Supplementation with DHA in Pediatric Patients with Cystic Fibrosis
CYSTIC FIBROSIS – DHA, Docosahexaenoic Acid, Omega-3 Fatty Acids
“Clinical effects of diet supplementation with DHA in pediatric patients suffering from cystic fibrosis,” Leggieri E, De Biase RV, et al, Minerva Pediatr, 2013 Aug; 65(4): 389-98. (Address: Centro Fibrosi Cistica Regione Lazio, Sapienza University, Rome, Italy.
In a study involving pediatric patients with cystic fibrosis, supplementation with the omega-3 fatty acid, DHA, for a period of 6 months, was found to be associated with improvements in clinical condition of patients, as well as reductions in pulmonary and intestinal inflammation. One g/10 kg/d was adminstered for the first month, followed by 250 mg/10 kg/d for the following 5 months. Results found reductions in IL-8, TNF-alpha in serum, and calprotectin in stools, as well as improvements in auxometric parameters and clinical condition. The authors conclude that DHA may have beneficial effects in pediatric patients with CF.
Probiotic Supplementation Reduces the Duration and Incidence of Infections in Elite Rugby Players
INFECTIONS, ATHLETES, IMMUNE FUNCTION – Probiotics
“Probiotic supplementation reduces the duration and incidence of infections but not severity in elite rugby union players,” Haywood BA, Black KE, et al, J Sci Sport, 2013 Aug 30; [Epub ahead of print]. (Address: Department of Human Nutrition, University of Otago, New Zealand).
In a randomized, placebo-controlled trial involving 30 elite rugby players, daily supplementation with probiotics for a period of 4 weeks was found to be associated with reduction in incidence of infections, while severity of symptoms while sick did not differ between the groups. Specifically, while receiving probiotics, 14 of the 30 subjects never experienced even a single upper respiratory tract infection or gastrointestinal episode, as compared to 6 of the 30 subjects while receiving a placebo. The mean number of days of illness was higher in the placebo group (5.8 days) as compared to the probiotic group (3.4 days). No significant difference in severity of symptoms when they arose was found between the groups. The authors conclude, “These positive effects of probiotic supplements provide evidence for the beneficial effects of daily supplementation with these probiotic strains in highly trained rugby union players.”