Expression of long non­coding RNA and mRNA in the hippocampus of mice with type 2 diabetes.

Long non­coding RNAs (lncRNAs) serve key roles in cell growth, development and various diseases associated with the central nervous system. However, differential expression profiles of lncRNAs in type 2 diabetes have not been reported. The present study aimed to analyze the expression pattern of lncRNA­mRNA in a type 2 diabetic mouse model using microarray analysis. The mouse model of type 2 diabetes was established and the total RNAs were extracted from the hippocampus of the mice used in the present study. The total RNAs were then examined by the GeeDom human lncRNA + mRNA V4.0 expression profile and analyzed through comparing Gene Ontology (GO) enrichment analysis and signal pathway analysis with the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. There were statistically significant differences between the expression of IncRNAs and mRNA in the healthy mice and that of the diabetic mice. In the diabetic mice, 130 different lncRNAs were expressed with 126  significantly upregulated and 4 significantly downregulated and 49 different mRNAs were detected with 45 significantly upregulated and 4 downregulated. GO analysis indicated that the mRNAs that are affected are involved in transport, cell adhesion, ion transport and metabolic processes. KEGG and Reactome enrichment analysis indicated that mRNAs impact on cholinergic synapses, nuclear factor­kB pathway, Toll like receptor 4 cascade and zinc transporter are correlated with cognitive dysfunction in type 2 diabetes. A dynamic lncRNA­mRNA network was constructed containing 123 lncRNAs and 48 mRNAs, which can elucidate the interaction between lncRNA and mRNA. Overall, this is the first study to indicate that lncRNAs are differentially expressed in the type 2 diabetic mice.

Cell density and serum exposure modify the function of the glucocorticoid receptor C/EBP complex.

The glucocorticoid receptor (GR) is a major control factor for proliferation, differentiation, and inflammation. Our knowledge about the GR is focused on its function as a transcription regulator. However, cells do not always respond to steroids in the same way or develop resistance. The mechanism underlying such a modified steroid response is not well understood, and may depend on the microenvironment of the cells or on the stage of their differentiation. Therefore, we studied the effect of cell density and inflammatory conditions on the expression, compartmentalization, activation, and the anti-proliferative function of the GR in primary human lung fibroblast cultures. In subconfluent cells the GR was located perinuclear, while in confluent cells it was ubiquitously expressed. Serum stimulation up-regulated the level of GR mRNA and protein under all conditions. In subconfluent cells dexamethasone activated the nuclear accumulation and DNA binding of the GR persistently, while in confluent cells its activity declined after 6 hours. In subconfluent cells, but not in confluent cells, the GR interacted with a 42-kD, but not the 30-kD C/EBP-alpha isoprotein, which resulted in an up-regulation of p21((Waf1/Cip1)) expression and suppression of proliferation. In confluent cells, glucocorticoids induced p27((Kip1)) expression via p38 mitogen-activated protein kinase and a 52-kD C/EBP-beta isoprotein. However, p27((Kip1)) did not mediate the antiproliferative effect of glucocorticoids, but simultaneous inhibition of p21((Waf1/Cip1)) and p27((Kip1)) unlocked contact inhibition in confluent cells. Our results indicate that cell density and serum exposure alter the localization and function of the GR.

Progressive pulmonary sarcoidosis--a fibroproliferative process potentially triggered by EGR-1 and IL-6.

BACKGROUND AND AIM OF THE WORK: Sarcoidosis is a chronic granulomatous disorder of unknown etiology. In most patients the disease is self-limited, although for reasons unclear, others progress or die from progressive organ fibrosis. Growth factors have been implicated in the pathogenesis of other fibrotic lung conditions. We have, therefore, examined the relationship between growth factor expression and disease phenotype in sarcoidosis. METHODS: Adopting a target gene approach utilizing gene expression arrays, growth factor gene expression profile was analyzed in the peripheral blood of 12 patients and 12 healthy controls. Expression, functional activity and the effect of oligonucleotide antisense treatment on selected proteins differentially expressed in progressive sarcoidosis were then tested in vitro on primary human lung fibroblasts. RESULTS: Genes regulating angiogenesis were preferentially upregulated in the self-limited form of disease, while early growth response-1 and interleukin-6 were predominantly activated in progressive sarcoidosis. Increased expression of early growth response-1 in sarcoid lung was confirmed by immunohistochemistry. Stimulated human fibroblasts also rapidly expressed interleukin-6 and early growth response-1 and these proteins were found to mediate serum-induced fibroblast proliferation as proliferation could be significantly abrogated with interleukin-6 and early growth response-1 antisense oligonucelotides. CONCLUSION: We conclude that progressive pulmonary sarcoidosis is characterized by a fibroproliferative dysregulation potentially triggered by early growth response-1 and interleukin-6. Our disease model underlines the inability of steroids to prevent ongoing fibroproliferation in the lung.