1.
Gene expression of thrombomodulin, TNF-α and NF-KB in coronary artery disease patients of Pakistan.
Rafiq, M, Liaquat, A, Saeed, N, Shamshad, GU, Mumtaz, S, Khan, MJ
Molecular biology reports. 2020;(10):7575-7582
Abstract
Thrombomodulin (THBD) is an endothelial surface glycoprotein receptor, having a pivotal role in maintaining laminar blood flow. It functions to protect endothelial integrity by exhibiting anti-coagulation and anti-inflammatory properties thereby playing a key role in cardiovascular disease (CVD) pathology. Cholesterol lowering drugs have shown to alter the anti-inflammatory effects of cytokines. Understanding the molecular aspects of THBD gene and its relation to inflammatory cytokines is important to identify new prognostic and therapeutic targets for the CVD treatments. The present study was conducted to measure the expression of THBD, TNF-α and NF-kB genes in coronary artery disease patients (CAD) in Pakistani population. Lipid profile and BMI was compared both on fifty CAD patients and fifty healthy individuals. Expression analysis for THBD, TNF-α and NF-kB was carried out using real time PCR. The effect of lipid lowering drugs on cardiometabolic risk variables especially gene expression was analyzed. Our results indicated that the difference in BMI was marginal; however LDL-cholesterol and triglycerides levels in CAD patients were significantly higher than healthy individuals. THBD gene was significantly up-regulated whereas TNF-α and NF-kB were significantly down regulated in CAD individuals. Further exploration revealed that these variations were accounted to the use of statins by the patients. The use of statins by CAD patients up-regulated the mRNA expression of THBD by down-regulation of inflammatory mediators. The enhanced expression of endothelial THBD in response to cholesterol lowering drugs establishes a novel pleiotropic target that can be of clinical significance in thromboembolic and inflammatory disorders.
2.
Iron Prevents Hypoxia-Associated Inflammation Through the Regulation of Nuclear Factor-κB in the Intestinal Epithelium.
Simmen, S, Cosin-Roger, J, Melhem, H, Maliachovas, N, Maane, M, Baebler, K, Weder, B, Maeyashiki, C, Spanaus, K, Scharl, M, et al
Cellular and molecular gastroenterology and hepatology. 2019;(2):339-355
Abstract
BACKGROUND & AIMS Hypoxia-associated pathways influence the development of inflammatory bowel disease. Adaptive responses to hypoxia are mediated through hypoxia-inducible factors, which are regulated by iron-dependent hydroxylases. Signals reflecting oxygen tension and iron levels in enterocytes regulate iron metabolism. Conversely, iron availability modulates responses to hypoxia. In the present study we sought to elucidate how iron influences the responses to hypoxia in the intestinal epithelium. METHODS Human subjects were exposed to hypoxia, and colonic biopsy specimens and serum samples were collected. HT-29, Caco-2, and T84 cells were subjected to normoxia or hypoxia in the presence of iron or the iron chelator deferoxamine. Changes in inflammatory gene expression and signaling were assessed by quantitative polymerase chain reaction and Western blot. Chromatin immunoprecipitation was performed using antibodies against nuclear factor (NF)-κB and primers for the promoter of tumor necrosis factor (TNF) and interleukin (IL)1β. RESULTS Human subjects presented reduced levels of ferritin in the intestinal epithelium after hypoxia. Hypoxia reduced iron deprivation-associated TNF and IL1β expression in HT-29 cells through the induction of autophagy. Contrarily, hypoxia triggered TNF and IL1β expression, and NF-κB activation in Caco-2 and T84 cells. Iron blocked autophagy in Caco-2 cells, while reducing hypoxia-associated TNF and IL1β expression through the inhibition of NF-κB binding to the promoter of TNF and IL1β. CONCLUSIONS Hypoxia promotes iron mobilization from the intestinal epithelium. Hypoxia-associated autophagy reduces inflammatory processes in HT-29 cells. In Caco-2 cells, iron uptake is essential to counteract hypoxia-induced inflammation. Iron mobilization into enterocytes may be a vital protective mechanism in the hypoxic inflamed mucosa.