Neither macro- nor micronutrient supplements have been clearly demonstrated to reduce the risk of preterm birth. However, there has been little attention to carotenoids, tocopherols, and long-chain fatty acids other than n-3 polyunsaturates.
We conducted a case-control study nested in a large (n = 5337) prospective, multicenter cohort. All cohort women had an interview, examination, and venipuncture at 24-26 weeks' gestation. Frozen plasma samples in spontaneous preterm births (n = 207) and approximately 2-term controls per case (n = 443) were analyzed for carotenoids, retinol, tocopherols, and long-chain fatty acids. Fresh placentas were fixed, stained, and assessed (without knowledge of pregnancy outcome) for histologic evidence of infection or inflammation, decidual vasculopathy, and infarction.
High (above the median) plasma concentrations of alpha- and beta-carotene, alpha- and beta-cryptoxanthin, and lycopene were all associated with reductions in risk of spontaneous preterm birth, with evidence of dose-response effects across quartiles. Modest increases in risk were observed with elevated total monounsaturated, total polyunsaturated, and total n-6 polyunsaturated long-chain fatty acids concentrations. Paradoxically, a high gamma-tocopherol concentration was associated with increased preterm birth risk (adjusted odds ratio = 1.8 [95% confidence interval = 1.2-2.6]). Only one of the studied micronutrients (lutein) was independently associated with a reduced risk of decidual vasculopathy (0.5 [0.3-0.9]).
Carotenoids and long-chain fatty acids warrant further investigation in in vitro, animal, and human studies of preterm birth.
The mechanisms involved in thyroid homeostasis are complex, and perfluoroalkyl substances (PFASs) have been indicated to interfere at several levels in this endocrine system. Disruption of the maternal thyroid homeostasis during early pregnancy is of particular concern, where subclinical changes in maternal thyroid hormones (THs) may affect embryonic and foetal development. The present study investigated associations between THs, thyroid binding proteins (TH-BPs) and PFAS concentrations in pregnant women from Northern Norway. Women participating in The Northern Norway Mother-and-Child contaminant Cohort Study (MISA) donated a blood sample at three visits related to their pregnancy and postpartum period (during the second trimester, 3 days and 6 weeks after delivery) in the period 2007-2009. Participants were assigned to quartiles according to PFAS concentrations during the second trimester and mixed effects linear models were used to investigate potential associations between PFASs and repeated measurements of THs, TH-BPs, thyroxin binding capacity and thyroid peroxidase antibodies (anti-TPOs). Women within the highest perfluorooctane sulfonate (PFOS) quartile had 24% higher mean concentrations of thyroid stimulating hormone (TSH) compared to the first quartile at all sampling points. Women within the highest quartiles of perfluorodecanoate (PFDA) had 4% lower mean concentrations of triiodothyronine (T3) and women within the highest quartile of perfluoroundecanoate (PFUnDA) had 3% lower mean concentrations of free triiodothyronine (FT3). Further, the difference in concentrations and the changes between three time points were the same for the PFAS quartiles. Thyroxin binding capacity was associated with all the THs and TH-BPs, and was selected as a holistic adjustment for individual changes in TH homeostasis during pregnancy. Finally, adjusting for maternal iodine status did not influence the model predictions. Findings in the present study suggest modifications of TH homeostasis by PFASs in a background exposed maternal population. The variation in levels of THs between PFAS quartiles was within normal reference ranges and may not be of clinical significance in the pregnant woman. However, subtle individual changes in maternal THs may have significant consequences for foetal health.
We studied the association and agreement between questionnaire data and biomarkers of marine food among Greenland Inuit.
Cross sectional study.
The study population comprised 2,224 Inuit, age 18+ (43% men); data collected 2005-2008 in Greenland. Using a food frequency questionnaire (FFQ), we calculated consumption of seal, whale, and fish (g/day) and as meals/month, intake of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), total N3, and mercury. We measured erythrocyte membrane fatty acids (FA) and whole blood mercury (Hg). Associations were assessed by Pearson correlation and agreement between the 2 methods was assessed by Bland-Altman plots depicting mean difference between the methods. Using multiple linear regressions, the associations were studied between whole blood mercury, erythrocyte FA and frequency or gram per day of seal, whale, and fish.
Little is known about the associations of serum fatty acids with lipoprotein profile and the underlying genetic and environmental etiology of these relationships. We aimed to analyze the phenotypic association of serum n-6 and n-3 polyunsaturated (PUFAs), monounsaturated (MUFAs) and saturated (SFAs) fatty acids (relative proportion to total fatty acids) with lipids and lipoproteins, and to quantify common genetic and environmental factors determining their covariation.
Two cohorts of healthy Finnish twins were assessed in young adulthood. Data were available for 1269 individual twins including 561 complete pairs. Serum metabolites were measured by nuclear magnetic resonance spectroscopy. Bivariate quantitative genetic models were used to decompose the phenotypic covariance between the pairs of traits into genetic and environmental components.
Among the strongest correlations observed, serum total n-6 PUFAs and linoleic acid were inversely (max. r=-0.65) and MUFAs positively (max. r=0.63) correlated with triglycerides and very low-density lipoprotein (VLDL) particle concentration, particularly with large VLDL (for n-6 PUFAs) and medium VLDL (for MUFAs). Genetic factors significantly contributed to their covariance with bivariate heritability estimates ranging from 44% to 56% for n-6 PUFAs and 58% to 66% for MUFAs. Genetic correlations with lipid traits were moderate to high (max. rA=-0.59 and 0.70 for n-6 PUFAs and MUFAs, respectively). Statistically significant, but substantially weaker phenotypic correlations of total n-3 PUFAs, docosahexaenoic acid (DHA) and SFAs with lipoprotein profile were not decomposed into their genetic and environmental components.
Shared genetic factors are important in explaining why higher concentrations of serum n-6 PUFAs and lower concentrations of serum MUFAs strongly associate with lower triglyceride and VLDL particle concentrations.
Institute of Clinical Sciences, Internal Medicine (YM, HC, JV, AS, JK, and ML), the Institute of Biomedicine Physiology (JÅ), and the Institute of Public Health and Clinical Nutrition (MU and US), University of Eastern Finland, Kuopio, Finland, and the Research Unit (MU) and the Department of Medicine (HC, JK, and ML), Kuopio University Hospital, Kuopio, Finland.
The significance of erythrocyte membrane fatty acids (EMFAs) and their ratios to predict hyperglycemia and incident type 2 diabetes is unclear.
We investigated EMFAs as predictors of the worsening of hyperglycemia and incident type 2 diabetes in a 5-y follow-up of a population-based study.
We measured EMFAs in 1346 Finnish men aged 45-73 y at baseline [mean ± SD age: 55 ± 6 y; body mass index (in kg/m(2)): 26.5 ± 3.5]. Our prospective follow-up study included only men who were nondiabetic at baseline and who had data available at the 5-y follow-up visit (n = 735).
Our study showed that, after adjustment for confounding factors, palmitoleic acid (16:1n-7; P = 2.8 × 10(-7)), dihomo-?-linolenic acid (20:3n-6; P = 2.3 × 10(-4)), the ratio of 16:1n-7 to 16:0 (P = 1.6 × 10(-8)) as a marker of stearoyl coenzyme A desaturase 1 activity, and the ratio of 20:3n-6 to 18:2n-6 (P = 9.4 × 10(-7)) as a marker of ?(6)-desaturase activity significantly predicted the worsening of hyperglycemia (glucose area under the curve in an oral-glucose-tolerance test). In contrast, linoleic acid (18:2n-6; P = 0.0015) and the ratio of 18:1n-7 to 16:1n-7 (P = 1.5 × 10(-9)) as a marker of elongase activity had opposite associations. Statistical significance persisted even after adjustment for baseline insulin sensitivity, insulin secretion, and glycemia. Palmitoleic acid (P = 0.010) and the ratio of 16:1n-7 to 16:0 (P = 0.004) nominally predicted incident type 2 diabetes, whereas linoleic acid had an opposite association (P = 0.004), and n-3 polyunsaturated fatty acids did not show any associations.
EMFAs and their ratios are associated longitudinally with changes in glycemia and the risk type 2 diabetes.
To examine correlations between bile lipid composition and fatty acid composition of blood serum in cholelithiasis patients.
Cholelithiasis prevalence in Khakasia Republic was studied in a clinico-epidemiological trial with participation of 1393 European people and 1060 mongoloid people--Khakasians. Bile lipids and serum fatty acids were measured.
Europeans had cholelithiasis in 7.3%, Khakasians--3.4% (p
Long-chain n-3 PUFA from fish have been associated with lower risk of CVD. Fish may also contain methylmercury, which may attenuate the inverse associations of the long-chain n-3 PUFA. However, the mechanisms underlying these associations are not fully known. We evaluated the associations of the serum long-chain n-3 PUFA (EPA, DPA and DHA) and hair Hg with resting heart rate (HR), peak HR during cycle ergometer exercise and HR recovery after exercise. A total of 1008 men from the population-based Kuopio Ischaemic Heart Disease Risk Factor Study, aged 42-60 years and free of CVD, were studied. After multivariate-adjustments in ANCOVA, higher serum total long-chain n-3 PUFA concentration was associated with lower resting HR (extreme-quartile difference 2·2 beats/min; 95 % CI 0·2, 4·1, P trend across quartiles=0·02), but not with peak HR or HR recovery. Associations were generally similar when EPA, DPA and DHA were evaluated individually, except for DPA, which was also associated with better HR recovery after exercise (extreme-quartile difference 2·1 beats/min; 95 % CI 0·1, 4·2, P trend=0·06). Higher hair Hg content had a trend towards lower peak HR after adjusting for the long-chain n-3 PUFA (P trend=0·05), but it only slightly attenuated the associations of the serum long-chain n-3 PUFA with HR. These findings suggest that higher serum long-chain n-3 PUFA concentrations are associated with lower resting HR in middle-aged men from Eastern Finland, which may partially explain the potential cardioprotective effect of fish intake.
Fatty acid compositions of serum cholesteryl esters (CE) were analysed with gas chromatography from a total of 1,348 Finnish children. The study was a part of a comprehensive survey of atherosclerosis precursors among children, and included 3-, 6-, 9-, 12-, 15-, and 18-year-old children and adolescents from five urban and twelve rural communities in Finland. In all age groups and both sexes, the mean percentages of linoleate (CE-18:2) were lower and those of saturated and monounsaturated fatty acids higher in eastern rural areas than elsewhere. Eastern rural children also had significantly higher proportions of omega 3 polyunsaturated fatty acids in their serum CE's. The percentage of serum CE-18:2 parallels the P/S values obtained by a dietary survey from the same populations. The reason for higher percentages of the omega 3 fatty acids in rural communities cannot be explained by diet, and remains unclear.
Ninety seven geriatric patients from two Danish homes for old people accepted to participate in a blinded experiment designed to counteract ageing phenomena. The subjects were split into two groups, i.e., the verum and the placebo group. The verum group received daily for one year an antioxidative cocktail consisting of: 300 micrograms selenium as L-selenomethionine, 45 mg zinc, 270 mg vitamin C, 2.7 mg vitamin A, 6 mg vitamin B-6, and 465 mg vitamin E (d-alfatocopherol). Furthermore, in order to enhance exchange in polyenoic acids, each subject received daily 250 mg gamma-linolenic acid. The placebo groups received similar looking pills and capsules without the active components. During one year in the verum group, the whole blood selenium, the hydrogen-dependent glutathione peroxidase (GSH-Px) of erythrocytes, and the vitamin E level in serum was found increased compared to the pretreatment values and to the placebo group. No change could be traced in the t-butylhydroperoxide dependent GSH-Px, an enzyme that also assays the glutathione-s-transferase. During the same period of time, the fasting levels of serum fatty acids and the content of lipofuscin in erythrocytes were estimated. Compared to the pretreatment values, the lipofuscin level declined significantly and the level of w-3 penta- and hexaenoic acids increased in the verum, but not in the placebo group. During the study period, slight, but significant improvements in psychological scores could be traced. Furthermore, the assays of bloodflow in different areas of the brain surface (i.e., the ISI values) revealed a general trend to improvement in all areas, when the ISI values were compared during treatment with the pretreatment values and the values in the placebo group.
The aims were to study biomarkers of systemic inflammation, platelet/endothelial activation and thrombosis in tunnel construction workers (TCW).
Biomarkers and blood fatty acids were measured in blood of 90 TCW and 50 referents before (baseline) and towards the end (follow-up) of a 12 days work period. They had been absent from work for 9 days at baseline. Air samples were collected by personal sampling.
Personal thoracic air samples showed geometric mean (GM) particulate matter and a-quartz concentrations of 604 and 74 µg/m(3), respectively. The arithmetic mean (AM) concentration of elemental carbon was 51 µg/m(3). The GM (and 95% confidence interval) concentration of the pro-inflammatory cytokine TNF-a decreased from 2.2 (2.0-2.4) at baseline to 2.0 pg/mL (1.8-2.2) (p?=?0.02) at follow-up among the TCW. Also the platelet activation biomarkers P-selectin and CD40L decreased significantly [25.4 (24.1-26.6) to 24.4 (22.9-26.0)] ng/mL, p?=?0.04 and 125 (114-137) to 105 (96-115) pg/mL, p?
Cites: Am J Respir Crit Care Med. 2007 Aug 15;176(4):395-40017446340