In 2010, the Mediterranean diet was recognized by UNESCO as an Intangible Cultural Heritage of Humanity. Olive oil is the most characteristic food of this diet due to its high nutraceutical value. The positive effects of olive oil have often been attributed to its minor components; however, its oleic acid (OA) content (70-80%) is responsible for its many health properties.
View Article and Find Full Text PDFThe present work investigates the modulation of grapefruit flavonoid naringenin over liver X receptor alpha (LXRα) and its target genes in THP-1 macrophages, focusing on AMP-activated protein kinase (AMPK) implication. Naringenin induced LXRα at mRNA and protein levels besides influencing the expression of LXRα target genes ABCA1, ABCG1 (ATP-binding cassette A1 and G1), and SREBP1c (sterol response element binding protein 1c) in THP-1 macrophages. The increased LXRα mRNA and protein expression was reverted when AMPK was inhibited by its chemical inhibitor, compound C or by transfection with AMPK α1 and α2 siRNA.
View Article and Find Full Text PDFPurpose: Oxysterols are cholesterol-oxygenated derivatives generated in the organism and also present in foods because of cholesterol oxidation during processing and storage. They are the natural ligands of liver X receptors (LXRs) and are generally recognized as hypocholesterolemic and anti-inflammatory molecules although this latter property is still controversial. Most oxysterol studies have been performed in macrophages, whereas the effects of oxysterols in neutrophils are poorly known.
View Article and Find Full Text PDFPurpose: Regulation of liver X receptors (LXRs) is essential for cholesterol homeostasis and inflammation. The present study was conducted to determine whether oleic acid (OA) could regulate mRNA expression of LXRα and LXRα-regulated genes and to assess the potential promotion of oxidative stress by OA in neutrophils.
Methods: Human neutrophils were treated with OA at different doses and LXR target gene expression, oxidative stress production, lipid efflux and inflammation state were analyzed.
Calcineurin (protein phosphatase 2B) (CN) comprises a family of serine/threonine phosphatases that play a pivotal role in signal transduction cascades in a variety of cells, including neutrophils. Angiotensin II (Ang II) increases both activity and de novo synthesis of CN in human neutrophils. This study focuses on the role that intracellular redox status plays in the induction of CN activity by Ang II.
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