The contribution of genotypes at the MICA gene triplet repeat polymorphisms and MEFV mutations to amyloidosis and course of the disease in the patients with familial Mediterranean fever
RHEUMATOLOGY INTERNATIONAL
Authors: Turkcapar, Nuran; Tuncali, Timur; Kutlay, Sim; Burhan, Basak Yalcin; Kinikli, Gulay; Erturk, Sehsuvar; Duman, Murat
Abstract
To evaluate the effects of MEFV genotypes and the major histocompatibility complex class I chain-related gene A (MICA) triplet repeat polymorphism on the severity and clinical features of familial Mediterranean fever (FMF) and amyloidosis in a group of Turkish FMF patients. We evaluated 105 adult FMF patients (with or without amyloidosis, 33 and 72, respectively) along with 107 healthy controls who were neither related to the patients nor had a family history of FMF or Behcet's disease. After recording the demographic and clinical data, the predominant mutations in the MEFV gene locus (M694V, M680I, V726A, M694I, and E148Q) were investigated by direct sequencing. MICA transmembrane polymorphisms in exon 5 were studied by vertical gel electrophoresis and fragment analysis of the amplicons obtained from MICA locus with appropriate primers. Earlier age at onset, increased frequency of attacks, arthritis attacks, erysipelas-like erythema, increased severity scores and amyloidosis were significantly more common in M694V homozygous patients compared to the patients not M694V homozygous (P = 0.005, OR 4.55; P = 0.001, OR 7.60; P = 0.003, OR 4.57; P = 0.002, OR 7.58; P = 0.004, OR 5.15 and P = 0.018, OR 3.33, respectively). We did not detect any modifying effects of MICA alleles as an independently risk factor on the amyloidosis development. However, when we examined the effects of MICA alleles on the course of the disease and development of amyloidosis in the M694V homozygous patients, A5 allele had a protective effect against the development of amyloidosis (P = 0.038, ORadj 0.26 with A5 and P = 0.009, ORadj 4.42 without A5). Though the effects of the MEFV genotypes seem clear, there are definitely other modifying factors or genes on the development of amyloidosis and on the course of the disease. For example, some MICA alleles have a protective effect on the prognostic factors in FMF.
White Adipose Tissue Response of Obese Mice to Ambient Oxygen Restriction at Thermoneutrality: Response Markers Identified, but no WAT Inflammation
GENES
Authors: Hoevenaars, Femke P. M.; Keijer, Jaap; van der Stelt, Inge; Duivenvoorde, Loes P. M.; Herreman, Laure; van Nes, Robin; Friedecky, David; Hegeman, Maria A.; van Schothorst, Evert M.
Abstract
Obesity is associated with white adipose tissue (WAT) hypoxia and inflammation. We aimed to test whether mild environmental oxygen restriction (OxR, 13% O-2), imposing tissue hypoxia, triggers WAT inflammation in obese mice. Thirteen weeks diet-induced obese male adult C57BL/6JOlaHsd mice housed at thermoneutrality were exposed for five days to OxR versus normoxia. WAT and blood were isolated and used for analysis of metabolites and adipokines, WAT histology and macrophage staining, and WAT transcriptomics. OxR increased circulating levels of haemoglobin and haematocrit as well as hypoxia responsive transcripts in WAT and decreased blood glucose, indicating systemic and tissue hypoxia. WAT aconitase activity was inhibited. Macrophage infiltration as marker for WAT inflammation tended to be decreased, which was supported by down regulation of inflammatory genes S100a8, Ccl8, Clec9a, Saa3, Mgst2, and Saa1. Other down regulated processes include cytoskeleton remodelling and metabolism, while response to hypoxia appeared most prominently up regulated. The adipokines coiled-coil domain containing 3 (CCDC3) and adiponectin, as well as the putative WAT hormone cholecystokinin (CCK), were reduced by OxR on transcript (Cck, Ccdc3) and/or serum protein level (adiponectin, CCDC3). Conclusively, our data demonstrate that also in obese mice OxR does not trigger WAT inflammation. However, OxR does evoke a metabolic response in WAT, with CCDC3 and adiponectin as potential markers for systemic or WAT hypoxia.