The 10th Congress of the International Society for the Study of Fatty Acids and Lipids (ISSFAL) convened May 26-30, in Vancouver, Canada, overlooking the North Shore Mountains, Coal Harbor and Stanley Park. Three days packed with meetings, breakfast workshops, plenary and poster sessions, exhibits and a gala dinner brought together scientists and others from 33 countries. All share an interest in current research on the biochemistry, health effects and genomics of fatty acids and lipids.
The conference program and abstracts can be downloaded here. Selected highlights from the meeting include:
- Several papers described research with resolvins and protectins regarding the resolution of inflammation; reduction in the time to resolve inflammatory responses; enhanced immune responses to airway inflammation from injury, infection and allergens; and their increased production with n-3 LC-PUFA supplementation in patients with chronic kidney disease.
- John Paul SanGiovanni described the activity of 4-HDHA, a metabolite generated by 5-lipoxygenase, and the complement system in the antiangiogenic properties of DHA in retinal neovascularization, which occurs in the advanced stages of age-related macular degeneration (AMD)
- Martha Neuringer detailed the effects of deficiencies in xanthophylls or n-3 LC-PUFAs or both on retinal structure and function in rhesus monkeys. Deficient animals developed premature signs of AMD and those deficient in n-3 LC-PUFAs also developed reduced rod sensitivity and selective losses in the central retina. Results suggest that both types of nutrients may help prevent AMD
- Cécilia Samieri assessed plasma EPA and DHA levels and their relationship to MRI images of brain in 65-year-old adults at baseline and after 4 years to evaluate changes in gray matter volume in the right hippocampus and right amygdala, semantic memory and depressive symptoms. Higher plasma EPA, but not DHA, was associated with less atrophy of gray matter in both brain regions and with less decline in semantic memory and less severe symptoms of depressive illness.
- Hiroshi Kawashima reported that among more than 1,100 Japanese adults aged 60 to 88 years, low serum levels of ARA and EPA were associated with a significantly higher risk of cognitive decline compared with participants in the third or fourth quintiles of these fatty acids.
- Bert Koletzko reported that for 1- to 11-year-old children with phenylketonuria (PKU), an inborn error of metabolism, who have very low protein intakes and no food sources of n-3 LC-PUFAs, supplementation with fish oil containing 15 mg DHA/ kg body weight for 3 months was associated with significantly improved visual evoked potential latencies, motor function and coordination. An ongoing multi-center study aims to determine the quantitative requirements for DHA in PKU children.
- David Ma presented details of a study in delta-6-desaturase knock-out mice and wild-type mice comparing the effects of a low or high ALA diet compared with a fish oil or lard diet on the development of hepatic steatosis and inflammation. They hoped to identify potential effects attributable solely to ALA. At 8 weeks, the hepatic inflammation scores for the ALA groups were intermediate between those of the lard and fish oil groups in both strains of mice. Hepatic steatosis scores were higher in the knock-out mice on the ALA diets compared with the wild-type mice. However, knock-out mice fed the high ALA or fish oil diets had less liver lipid compared with the lard-fed knock-out animals. The results suggested that ALA had direct effects on inflammation independent of conversion to long-chain forms, but that lack of conversion was associated with the development of fatty liver.
- Maria Makrides described findings from a supplementation study of 800 mg of DHA or vegetable oil in the last half of pregnancy on the risk of developing gestational diabetes or preeclampsia. There was no difference between the DHA-supplemented and control mothers in either outcome, but perinatal death and neonatal convulsions were significantly lower in the DHA group.
- Christopher Ramsden presented a detailed analysis of data from the Sydney Diet Heart Study in which linoleic acid intakes in middle-aged men with coronary heart disease increased from 8% to 15% of energy at the expense of saturated fat consumption. In a follow-up of 2 to 7 years, all cause mortality increased by 62%, CVD mortality by 70% and CHD mortality by 74% in the intervention group compared with the no-intervention control group. This analysis provides additional evidence that high intakes of linoleic acid are associated with increased risk of mortality, especially from heart disease.
- Richard Bazinet discussed the uptake and metabolism of PUFAs into the brain using radiolabelled fatty acids. Some PUFAs, such as ARA and DHA, are highly conserved and recycled, whereas others, such as EPA, are rapidly removed from the brain largely by beta-oxidation. These observations would explain why EPA levels are very low in the brain.
- Gunter Eckert reported that the brains of aged animals or those with neurodegenerative diseases exhibit reduced mitochondrial function, increased oxidative stress and greater synaptic dysfunction. Brain cells and mitochondria from aged brains have lower ATP levels, reduced respiration and less DHA. The provision of fish oil to young or old animals increased DHA concentrations in the brain, improved mitochondrial respiration and promoted the production of ATP.
- James Ntambi described the activity of stearoyl-CoA desaturase (SCD) enzyme in skin and its function in the synthesis of oleate and palmitoleate. Animals lacking this enzyme develop sebaceous gland hypoplasia and progressive hair loss with decreased levels of monounsaturated fatty acids and increased skin levels of retinol and retinoic acid. Feeding these animals diets high in oleate fails to increase skin levels of oleate or restore sebaceous gland lipids and normal hair growth. These observations suggest that SCD is important for normal skin function and retinol homeostasis, with implications for several human skin disorders, such as acne and seborrheic dermatitis.
- Alex Richardson and Paul Montgomery presented data from the DHA Oxford Learning and Behavior Study. Behavior, working memory and reading ability correlated with blood DHA levels in a large sample of 7-9 year old children from Oxfordshire who read at the 33rd percentile or lower. As part of a subsequent intervention with 600 mg of DHA per day for 16 weeks, they found that normal school children with reading difficulties, (test scores at the 20th percentile) showed significant improvement in reading performance after the intervention compared with the placebo group. Improvement in Parent-rated behavior also improved, but there was no benefit on memory.
- Susan Carlson reported that healthy pregnant women supplemented with 600 mg of DHA per day from 14 weeks’ gestation until delivery had a significantly increased gestation time from 272 to 276 days and their infants were significantly heavier, longer and had greater head circumferences compared with infants of mothers consuming a placebo supplement. DHA levels in the mothers and offspring were also increased.