ABSTRACT
Idiopathic pulmonary arterial hypertension (IPAH) is a fatal disease that comprises sustained vasoconstriction, enhanced proliferation of pulmonary vascular cells, and in situ thrombosis. The discovery of several contributing signaling pathways in recent years has resulted in an expanding array of novel therapies; however, IPAH remains a progressive disease with poor outcome in most instances. To identify new regulatory pathways of vascular remodeling in IPAH, we performed transcriptome-wide expression profiling of laser-microdissected pulmonary arterial resistance vessels derived from explanted IPAH and nontransplanted donor lung tissues. Statistical analysis of the data derived from six individuals in each group showed significant regulation of several mediators of the canonical and noncanonical WNT pathway. As to the noncanonical WNT pathway, the planar cell polarity (PCP) pathway, the ras homolog gene family member A (RHOA), and ras-related C3 botulinum toxin substrate-1 (RAC1) were strongly up-regulated. Real-time PCR of laser-microdissected pulmonary arteries confirmed these array results and showed in addition significant up-regulation of further PCP mediators wingless member 11 (WNT11), disheveled associated activator of morphogenesis-1 (DAAM1), disheveled (DSV), and RHO-kinase (ROCK). Immunohistochemical staining and semiquantitative expression analysis confirmed the markedly enhanced expression of the PCP mediators in the pulmonary resistance vessels, in particular in the endothelial layer in IPAH. Therefore we propose the PCP pathway to be critically involved in the regulation of vascular remodeling in IPAH.
Subject(s)
Gene Expression Regulation , Hypertension, Pulmonary/metabolism , Pulmonary Artery/pathology , Wnt Proteins/metabolism , Adult , Child, Preschool , Disease Progression , Female , Humans , Lung/metabolism , Lung Transplantation , Male , Microdissection , Middle Aged , Models, BiologicalABSTRACT
PURPOSE: We studied gene expression differences in brain homogenate, hippocampus, somatosensory cortex and cerebellum of rats suffering from sepsis-associated delirium and analyzed the effects of norepinephrine and 1,400 W (specific inhibitor of the inducible nitric-oxide synthase). METHODS: We applied microarray screenings to rat brain homogenate 1, 3 and 4.5 h after lipopolysaccharide (LPS, 5 mg/kg) or 0.9% NaCl treatment. Therapy groups were analyzed after 4.5 h. Validations and compartment specific investigations were carried out by real-time PCR. RESULTS: Most striking gene expression differences were seen 4.5 h after LPS administration, especially within the hippocampus (chemokines and endothelial cell-specific molecule 1). Norepinephrine resulted in a discrete chemokine up-regulation, while 1,400 W had hardly any effect. CONCLUSION: Strongest gene regulations were found within the hippocampus. Norepinephrine showed a tendency of having a proinflammatory influence, while 1,400 W had no clear-cut effect onto the gene expression level.