Perturbations in Blood Phosphatidylcholine and Sphingomyelin Fatty Acid Composition in a Sample Population of Cigarette Smokers

Docosahexaenoic (DHA) and arachidonic acids (AA) are polyunsaturated fatty acids (PUFAs), major components of brain tissue and neural systems, and the precursors of a number of biologically active metabolites with functions in inflammation resolution, neuroprotection and other actions. As PUFAs are highly susceptible to peroxidation, we hypothesised whether cigarette smokers would present altered PUFAs levels in plasma and erythrocyte phospholipids. Adult males from Indian, Sri-Lankan or Bangladeshi genetic backgrounds who reported smoking between 20 and 60 cigarettes per week were recruited. The control group consisted of matched non-smokers. A blood sample was taken, plasma and erythrocyte total lipids were extracted, phospholipids were separated by thin layer chromatography, and the fatty acid content analysed by gas chromatography. In smokers, dihomo-gamma-linolenic acid, the AA precursor, was significantly reduced in plasma and erythrocyte phosphatidylcholine. AA and DHA were significantly reduced in erythrocyte sphingomyelin. Relatively short term smoking has affected the fatty acid composition of plasma and erythrocyte phospholipids with functions in neural tissue composition, cell signalling, cell growth, intracellular trafficking, neuroprotection and inflammation, in a relatively young population. As lipid peroxidation is pivotal in the pathogenesis of atherosclerosis and neurodegenerative diseases such as Alzheimer disease, early effects of smoking may be relevant for the development of such conditions.

Omega-3 Fatty Acids are Related to Abnormal Emotion Processing in Adolescent Boys with Attention Deficit Hyperactivity Disorder

Background In addition to the core symptoms, attention deficit hyperactivity disorder (ADHD) is associated with poor emotion regulation. There is some evidence that children and young adults with ADHD have lower omega-3 levels and that supplementation with omega-3 can improve both ADHD and affective symptoms. We therefore investigated differences between ADHD and non-ADHD children in omega-3/6 fatty acid plasma levels and the relationship between those indices and emotion-elicited event-related potentials (ERPs). Methods Children/adolescents with (n=31) and without ADHD (n=32) were compared in their plasma omega-3/6 indices and corresponding ERPs during an emotion processing task. Results Children with ADHD had lower mean omega-3/6 and ERP abnormalities in emotion processing, independent of emotional valence relative to control children. ERP abnormalities were significantly associated with lower omega-3 levels in the ADHD group. Conclusions The findings reveal for the first time that lower omega-3 fatty acids are associated with impaired emotion processing in ADHD children.

Omega-3 Fatty Acids are Inversely Related to Callous and Unemotional Traits in Adolescent Boys with Attention Deficit Hyperactivity Disorder

A number of research studies have reported abnormal plasma fatty acid profiles in children with ADHD along with some benefit of n−3 to symptoms of ADHD. However, it is currently unclear whether (lower) long chain-polyunsaturated fatty acids (LC-PUFAs) are related to ADHD pathology or to associated behaviours. The aim of this study was to test whether (1) ADHD children have abnormal plasma LC-PUFA levels and (2) ADHD symptoms and associated behaviours are correlated with LC-PUFA levels. Seventy-two, male children with (n=29) and without a clinical diagnosis of ADHD (n=43) were compared in their plasma levels of LC-PUFA. Plasma DHA was higher in the control group prior to statistical correction. Callous–unemotional (CU) traits were found to be significantly negatively related to both eicosapentaenoic acid (EPA), and total omega-3 in the ADHD group. The findings unveil for the first time that CU and anti-social traits in ADHD are associated with lower omega-3 levels.

Deleterious Effects of Lard-enriched Diet on Tissues Fatty Acids Composition and Hypothalamic Insulin Actions

Altered tissue fatty acid (FA) composition may affect mechanisms involved in the control of energy homeostasis, including central insulin actions. In rats fed either standard chow or a lard-enriched chow (high in saturated/low in polyunsaturated FA, HS-LP) for eight weeks, we examined the FA composition of blood, hypothalamus, liver, and retroperitoneal, epididymal and mesenteric adipose tissues. Insulin-induced hypophagia and hypothalamic signaling were evaluated after intracerebroventricular insulin injection. HS-LP feeding increased saturated FA content in adipose tissues and serum while it decreased polyunsaturated FA content of adipose tissues, serum, and liver. Hypothalamic C20:5n-3 and C20:3n-6 contents increased while monounsaturated FA content decreased. HS-LP rats showed hyperglycemia, impaired insulin-induced hypophagia and hypothalamic insulin signaling. The results showed that, upon HS-LP feeding, peripheral tissues underwent potentially deleterious alterations in their FA composition, whist the hypothalamus was relatively preserved. However, hypothalamic insulin signaling and hypophagia were drastically impaired. These findings suggest that impairment of hypothalamic insulin actions by HS-LP feeding was not related to tissue FA composition.

Long Chain Saturated Fatty Acids Increase Haptoglobin Gene Expression in C57BL/6J Mice Adipose Tissue and 3T3-L1 Cells

Background Dietary lipids are directly related to the composition of adipose tissue, aetiology of obesity and arousal of obesity-related pathologies, like chronic inflammation states. Haptoglobin is an acute phase protein secreted by the liver and white adipose tissue, and its blood levels vary according to the volume of fat in the body. Aim of the study To investigate the effect of diets enriched with large amounts of dietary fats, which differ in their fatty acid composition, on the haptoglobin gene expression by visceral and subcutaneous adipose tissue of mice fed for 2 days or 8 weeks. 3T3-L1 cells were treated with fatty acids that are found in those types of dietary fats. Methods Mice were treated acutely (for 2 days) or chronically (for 8 weeks) with diets enriched with soybean oil, fish oil, coconut oil or lard. 3T3-L1 cells were treated with six different fatty acids. Haptoglobin gene expression was quantified by northern blotting. Results Both chronic and acute treatment with lard, which is rich in long chain saturated fatty acids, increased the haptoglobin mRNA expression in the retroperitoneal and epidydimal white adipose tissues. Chronic treatment with coconut oil, which is rich in medium chain saturated fatty acids, increased the haptoglobin expression in the epidydimal and subcutaneous depots. In 3T3-L1, palmitic acid increased the haptoglobin gene expression. Conclusion The type of lipids in the diet can differently modulate the white adipose tissue gene expression of haptoglobin, and saturated fatty acids play a major role in promoting a pro-inflammatory environment. This response is fat pad specific and dependant on the duration of treatment.