High Levels of Both n-3 and n-6 Long-Chain Polyunsaturated Fatty Acids in Cord Serum Phospholipids Predict Allergy Development

Abstract

BackgroundLong-chain polyunsaturated fatty acids (LCPUFAs) reduce T-cell activation and dampen inflammation. They might thereby counteract the neonatal immune activation and hamper normal tolerance development to harmless environmental antigens. We investigated whether fatty acid composition of cord serum phospholipids affects allergy development up to age 13 years.MethodsFrom a population-based birth-cohort born in 1996/7 and followed until 13 years of age (n = 794), we selected cases with atopic eczema (n = 37) or respiratory allergy (n = 44), as well as non-allergic non-sensitized controls (n = 48) based on diagnosis at 13 years of age. Cord and maternal sera obtained at delivery from cases and controls were analysed for proportions of saturated, monounsaturated and polyunsaturated fatty acids among serum phospholipids.ResultsThe cord serum phospholipids from subject who later developed either respiratory allergy or atopic eczema had significantly higher proportions of 5/8 LCPUFA species, as well as total n-3 LCPUFA, total n-6 LCPUFA and total LCPUFA compared to cord serum phospholipids from controls who did not develop allergy (P<0.001 for all comparisons). Conversely, individuals later developing allergy had lower proportion of the monounsaturated fatty acid 18∶1n-9 as well as total MUFA (p<0.001) among cord serum phospholipids. The risk of respiratory allergy at age 13 increased linearly with the proportion of n-3 LCPUFA (Ptrend<0.001), n-6 LCPUFA (Ptrend = 0.001), and total LCPUFA (Ptrend<0.001) and decreased linearly with the proportions of total MUFA (Ptrend = 0.025) in cord serum phospholipids. Furthermore, Kaplan-Meier estimates of allergy development demonstrated that total LCPUFA proportion in cord serum phospholipids was significantly associated with respiratory allergy (P = 0.008) and sensitization (P = 0.002), after control for sex and parental allergy.ConclusionA high proportion of long-chain PUFAs among cord serum phospholipids may predispose to allergy development. The mechanism is unknown, but may involve dampening of the physiologic immune activation in infancy needed for proper maturation of the infant's immune system.

Maternal dietary counseling during pregnancy and infant fatty acid profiles

“…Our findings confirm the delivery of maternal dietary changes during pregnancy to the infant, the TAG FA representing a biomarker of exposure to exogenous FA over a very recent period of dietary intake (Lagström et al, 1998). The modification of infant's FA status at an early stage may be of importance and carry long-term health benefits up to adulthood (Barman et al, 2013;Kaikkonen et al, 2012). Dietary counseling, an approach applicable to public health setting, resulted in increased intakes of nÀ3 FA in the intervention group over the entire course of pregnancy and lactation, also reported previously in the larger study population (Ilmonen et al, 2011;Piirainen et al, 2006) Continuous supply of FA from the usual diet was ensured through supporting dietary counseling with provision of rapeseed oil based food products from early pregnancy onwards.…”

“…Early modification of infant's FA status by increasing the proportion of unsaturated FA, particularly nÀ3 FA, may be of importance both in the short and long term, benefits possibly extending up to adulthood (Barman et al, 2013;Kaikkonen et al, 2012). However, as no changes in the CE FA or FA at 1 month of age were detected, it may be speculated that more drastic measures, such as supplementation of FA, in either maternal or infant diet may be necessary.…”

Does allergy begin in utero?

“…For example, one study found increased maternal fish intake protects against eczema at 1 year of age, and against atopy and atopic wheeze at 6 years, especially among children who were not breastfed . Maternal PUFA supplementation during pregnancy reduces atopic eczema and egg sensitization in the first year of life , yet higher levels of LCPUFAs in cord serum are associated with increased risk of allergy . Another study showed that during the first trimester, maternal shellfish consumption increases the risks of wheezing and eczema, and fatty fish consumption increases the risk of asthma, although lean fish and total fish consumption did not affect allergic disease risk .…”

Malnutrition, Immunodeficiency, and Mucosal Infection

“…A meta-analysis concluded that maternal supplementation during pregnancy with n-3 PUFA was associated with decreased childhood asthma, allergic skintest responses to egg, and reduced levels of interleukin (IL)-13 (Klemens et al, 2011). However a recently reported study of neonatal cord blood levels showed that risk of respiratory allergy at age 13 years increased linearly with the proportion of n-3 or n-6 PUFA in cord blood serum and decreased linearly with the proportions of total medium chain PUFA levels, suggesting to the investigators that reduced inflammatory response in this period may prevent activation of immune response, leading to tolerance toward harmless environmental antigens (Barman et al, 2013). PUFAs target T-helper type 1 (Th1) cells activated by microbial exposure, whereas Th2 cells, which support the development of IgEmediated allergy, are not suppressed by either n-3 or n-6 PUFAs to the same extent (Wallace et al, 2001).…”