Spleen Tyrosine Kinase (Syk) Regulates Systemic Lupus Erythematosus (SLE) T Cell Signaling

Engagement of the CD3/T cell receptor complex in systemic lupus erythematosus (SLE) T cells involves Syk rather than the zeta-associated protein. Because Syk is being considered as a therapeutic target we asked whether Syk is central to the multiple aberrantly modulated molecules in SLE T cells. Using a gene expression array, we demonstrate that forced expression of Syk in normal T cells reproduces most of the aberrantly expressed molecules whereas silencing of Syk in SLE T cells normalizes the expression of most abnormally expressed molecules. Protein along with gene expression modulation for select molecules was confirmed. Specifically, levels of cytokine IL-21, cell surface receptor CD44, and intracellular molecules PP2A and OAS2 increased following Syk overexpression in normal T cells and decreased after Syk silencing in SLE T cells. Our results demonstrate that levels of Syk affect the expression of a number of enzymes, cytokines and receptors that play a key role in the development of disease pathogenesis in SLE and provide support for therapeutic targeting in SLE patients

FADS2 Function Loss at the Cancer Hotspot 11q13 Locus Diverts Lipid Signaling Precursor Synthesis to Unusual Eicosanoid Fatty Acids

Background: Genes coding for the fatty acid desaturases (FADS1, 2, 3) localized at the cancer genomic hotspot 11q13 locus are required for the biosynthesis of 20 carbon polyunsaturated fatty acids (PUFA) that are direct eicosanoid precursors. In several cancer cell lines, FADS2 encoded D6 and D8 desaturation is not functional. Methodology/Principal Findings: Analyzing MCF7 cell fatty acids with detailed structural mass spectrometry, we show that in the absence of FADS2 activity, the FADS1 product D5-desaturase operates to produce 5,11,14–20:3 and 5,11,14,17–20:4. These PUFA are missing the 8–9 double bond of the eicosanoid signaling precursors arachidonic acid (5,8,11,14–20:4) and eicosapentaenoic acid (5,8,11,14,17–20:5). Heterologous expression of FADS2 restores D6 and D8-desaturase activity and normal eicosanoid precursor synthesis. Conclusions/Significance: The loss of FADS2-encoded activities in cancer cells shuts down normal PUFA biosynthesis, deleting the endogenous supply of eicosanoid and downstream docosanoid precursors, and replacing them with unusual butylene-interrupted fatty acids. If recapitulated in vivo, the normal eicosanoid and docosanoid cell signaling milieu would be depleted and altered due to reduction and substitution of normal substrates with unusual substrates, with unpredictable consequences for cellular communication

Habitual snoring and atopic state: correlations with respiratory function and teeth occlusion

<p>Abstract</p> <p>Background</p> <p>Allergy represents a risk factor at the base of sleep-disordered breathing in pediatric age. Among allergic diseases, the atopy is characterized by a tendency to be “hyperallergic.” Sleep-disordered breathing is also known in orthodontics as correlated with the morphology of craniofacial complex. The aim of this study was to investigate the relation between atopy and sleep-disordered breathing (oral breathers with habitual snoring), comparing atopic children with sleep-disordered breathing (test group) with nonatopic ones with sleep-disordered breathing (control group), in the prevalence of dento-skeletal alterations and other risk factors that trigger sleep-disordered breathing, such as adenotonsillar hypertrophy, turbinate hypertrophy, obesity, and alteration of oxygen arterial saturation.</p> <p>Methods</p> <p>In a group of 110 subjects with sleep-disordered breathing (6 to 12 years old), we grouped the subjects into atopic (test group, 60 subjects) and nonatopic (control group, 50 subjects) children and compared the data on the following: skin allergic tests, rhinoscopy, rhinomanometry, night home pulsoxymetry, body mass index, and dento-facial alterations.</p> <p>Results</p> <p>Even if our results suggest that atopy is not a direct risk factor for sleep-disordered breathing, the importance of a physiologic nasal respiration in the pathogenesis of sleep-disordered breathing seems to be demonstrated in our study by the higher prevalence of hypertrophy in the adenotonsillar lymphatic tissue, odontostomatological alterations, alterations of the oxygen saturation to pulsoxymetry, and higher prevalence of obesity observed in our children with sleep-disordered breathing, in percentages higher than that of the general pediatric population previously observed in the literature.</p> <p>Conclusions</p> <p>The importance of a physiologic nasal respiration in the pathogenesis of sleep-disordered breathing is demonstrated in our study.</p