Serum Polyunsaturated Fatty Acids in Middle Childhood and Body Mass Index Change Through Adolescence

Background: Polyunsaturated fatty acids (PUFA) status in childhood may be associated with adiposity development. Objective: To assess associations of serum PUFA biomarkers in childhood with change in body mass index (BMI)-for-age Z scores (BMIZ) through adolescence. Methods: We quantified serum PUFA at ages 5 and 10 years among 418 children from Santiago, Chile. BMI was measured at 5, 10, and 16 years. We compared BMIZ change through age 16 years between quartiles of PUFA at 5 and 10 years and PUFA change 5–10 years by fitting growth curves from mixed effects models. Results: At age 5 years, serum docosahexaenoic acid was inversely associated with BMIZ change from ages 5 to 16 years. At age 10 years, arachidonic acid (AA) was nonlinearly positively related to BMIZ change from ages 10 to 16 years. Change in AA and the Δ5-desaturase (D5D) activity index between 5 and 10 years were each positively associated with BMIZ change from ages 10 to 16 years. Change in eicosapentaenoic acid was inversely associated with change in BMIZ. Conclusions: Serum long-chain n-3 PUFA in middle childhood were associated with less BMI gain through adolescence, whereas AA and D5D activity was related to greater BMI gain.

Deficiency of long-chain polyunsaturated fatty acids in phenylketonuria: a cross-sectional study

Deficiency of long-chain polyunsaturated fatty acids in phenylketonuria: a cross-sectional study Abstract The etiology of altered blood fatty acid (FA) profile in phenylketonuria (PKU) is understood only partially. We aimed to determine whether FAs deficiency is dependent on diet or metabolic disturbances. The study comprised 40 PKU patients (20 female, 20 male; aged 11 to 35 years; 12 children and 28 adults) and 40 healthy subjects (HS; 20 female, 20 male, aged 18 to 33 years). We assessed the profile of FAs (gas chromatography/mass spectrometry) and analyzed the 72-hour dietary recalls. The amount of C14:0, C16:0 and C16:1n-7, C18:1n-9 did not differ between the analyzed groups. The percentage of C18:0 was higher, while C20:3n-9, C18:2n-6, C20:2n-6, C20:4n-6, C22:4n-6, C22:5n-6 and C22:6n-3 was lower in PKU than in HS. However, C18:3n-6, C18:3n-3 and n-6/n-3 ratio were higher in PKU patients. The C20:4n-6/C20:3n-6 ratio (reaction catalyzed by Δ5-desaturase), the C22:5n-6/C22:4n-6 and the C22:6n-3/C22:5n-3 ratio (both reactions catalyzed by Δ6-desaturase) were significantly lower in PKU patients. The deficiency of long-chain polyunsaturated fatty acids in PKU patients may result not only from inadequate supply but also from metabolic disturbances.

Exploring the Biosynthesis of Unsaturated Fatty Acids in Bacillus cereus ATCC 14579 and Functional Characterization of Novel Acyl-Lipid Desaturases

ABSTRACTAt low temperatures,Bacillus cereussynthesizes large amounts of unsaturated fatty acids (UFAs) with double bonds in positions Δ5 and Δ10, as well as Δ5,10 diunsaturated fatty acids. Through sequence homology searches, we identified two open reading frames (ORFs) encoding a putative Δ5 desaturase and a fatty acid acyl-lipid desaturase in theB. cereusATCC 14579 genome, and these were named BC2983 and BC0400, respectively. Functional characterization of ORFs BC2983 and BC0400 by means of heterologous expression inBacillus subtilisconfirmed that they both encode acyl-lipid desaturases that use phospholipids as the substrates and have Δ5 and Δ10 desaturase activities. Thus, these ORFs were correspondingly nameddesA(Δ5 desaturase) anddesB(Δ10 desaturase). We established that DesA utilizes ferredoxin and flavodoxins (Flds) as electron donors for the desaturation reaction, while DesB preferably employs Flds. In addition, increased amounts of UFAs were found whenB. subtilisexpressingB. cereusdesaturases was subjected to a cold shock treatment, indicating that the activity or the expression of these enzymes is upregulated in response to a decrease in growth temperature. This represents the first work reporting the functional characterization of fatty acid desaturases fromB. cereus.