Chemokine receptors and their therapeutic opportunities in diseased lung: far beyond leukocyte trafficking.

Chemokine receptors and their chemokine ligands, key mediators of inflammatory and immune cell trafficking, are involved in the regulation of both physiological and pathological processes in the lung. The discovery that chemokine receptors/chemokines, typically expressed by inflammatory and immune cells, are also expressed in structural lung tissue cells suggests their role in mediating the restoration of lung tissue structure and functions. Thus, chemokine receptors/chemokines contribute not only to inflammatory and immune responses in the lung but also play a critical role in the regulation of lung tissue repair, regeneration, and remodeling. This review aims to summarize current state-of-the-art on chemokine receptors and their ligands in lung diseases such as chronic obstructive pulmonary disease, asthma/allergy, pulmonary fibrosis, acute lung injury, and lung infection. Furthermore, the therapeutic opportunities of chemokine receptors in aforementioned lung diseases are discussed. The review also aims to delineate the potential contribution of chemokine receptors to the processes leading to repair/regeneration of the lung tissue.

Involvement of microRNAs in physiological and pathological processes in the lung.

To date, at least 900 different microRNA (miRNA) genes have been discovered in the human genome. These short, single-stranded RNA molecules originate from larger precursor molecules that fold to produce hairpin structures, which are subsequently processed by ribonucleases Drosha/Pasha and Dicer to form mature miRNAs. MiRNAs play role in the posttranscriptional regulation of about one third of human genes, mainly via degradation of target mRNAs. Whereas the target mRNAs are often involved in the regulation of diverse physiological processes ranging from developmental timing to apoptosis, miRNAs have a strong potential to regulate fundamental biological processes also in the lung compartment. However, the knowledge of the role of miRNAs in physiological and pathological conditions in the lung is still limited. This review, therefore, summarizes current knowledge of the mechanism, function of miRNAs and their contribution to lung development and homeostasis. Besides the involvement of miRNAs in pulmonary physiological conditions, there is evidence that abnormal miRNA expression may lead to pathological processes and development of various pulmonary diseases. Next, the review describes current state-of-art on the miRNA expression profiles in smoking-related diseases including lung cancerogenesis, in immune system mediated pulmonary diseases and fibrotic processes in the lung. From the current research it is evident that miRNAs may play role in the posttranscriptional regulation of key genes in human pulmonary diseases. Further studies are, therefore, necessary to explore miRNA expression profiles and their association with target mRNAs in human pulmonary diseases.

XB130 deficiency enhances lipopolysaccharide-induced septic response and acute lung injury.

XB130 is a novel oncoprotein that promotes cancer cell survival, proliferation and migration. Its physiological function in vivo is largely unknown. The objective of this study was to determine the role of XB130 in lipopolysaccharide (LPS)-induced septic responses and acute lung injury. LPS was intraperitoneally administrated to Xb130 knockout (KO) and wild type (WT) mice. There was a significant weight loss in KO mice at Day 2 and significantly higher disease scores during the 7 days of observation. The levels of tumor necrosis factor-alpha, monocyte chemoattractant protein-1, interleukin-6 and interleukin-10 in the serum were significantly higher in KO mice at Day 2. In KO mice there were a significantly higher lung injury score, higher wet/dry lung weight ratio, more apoptotic cells and less proliferative cells in the lung. Macrophage infiltration was significantly elevated in the lung of KO mice. There was significantly increased number of p-GSK-3ß positive cells in KO mice, which were mainly neutrophils and macrophages. XB130 is expressed in alveolar type I and type II cells in the lung. The expression in these cells was significantly reduced after LPS challenge. XB130 deficiency delayed the recovery from systemic septic responses, and the presence of XB130 in the alveolar epithelial cells may provide protective mechanisms by reducing cell death and promoting cell proliferation, and reducing pulmonary permeability.

Early and subacute inflammatory response and long-term survival after hip trauma and surgery.

BACKGROUND: Hip fractures represent major source of morbidity in elderly patients. There is little evidence about the impact of inflammatory changes induced by hip trauma and surgery on long term survival. METHODS: We evaluated the prognostic significance of the surgery-related dynamics of white blood cell count (WBC), neutrophil to lymphocyte ratio (NLR), C-reactive protein (CRP), interleukin-6 (IL-6) and soluble adhesion molecules (including P-selectin, E-selectin and VCAM) on survival in 104 consecutive patients with traumatic hip fractures recruited within the 2 years period. RESULTS: In surviving patients, the minimum follow-up length was 48 and maximum 84 months (median 60 months). The mean age of the population was 80 ± 9 years, 72% were women. The survival rates were 69%, 45% and 38% at one, three and five years of the follow-up, respectively. Baseline serum creatinine, older age and subdural anesthesia type were associated with worse survival. The acute inflammatory response failed to predict the long term survival. In contrast, elevated WBC and IL-6 as assessed 21 days after the surgery were associated with a significantly worse outcome. CONCLUSION: The survival of elderly patients undergoing the surgery for acute hip fracture is unfavorable. In contrast to previous reports, we did not confirm that acute inflammatory response to the surgery predicts the long-term survival. On the contrary, persistent elevation of WBC and IL-6 three weeks after the surgery indicates a poor outcome.

Extrapulmonary involvement in patients with sarcoidosis and comparison of routine laboratory and clinical data to pulmonary involvement.

INTRODUCTION: Patients with pulmonary and pulmonary plus extrapulmonary sarcoidosis differ in symptom severity and health status impairment. To date there is no information on differences in clinical and laboratory parameters between these phenotypes and limited information on extrapulmonary involvement in Czech sarcoidosis patients exists. METHODS: We therefore compared clinical data (age, gender, organ involvement, lung function tests) and laboratory data (blood counts, bronchoalveolar fluid (BAL) cellular profile, serum levels of CRP, SACE, sIL-2R, neopterin) between patients with newly diagnosed pulmonary sarcoidosis (n=107) and those with pulmonary plus extrapulmonary sarcoidosis (n=54). RESULTS: Extrapulmonary sarcoidosis was diagnosed in 33% of patients, mostly affecting lymph nodes and skin and having hypercalciuria. There was no difference in the prevalence of extrapulmonary sarcoidosis between genders. Patients with extrapulmonary sarcoidosis were older and mostly non-smokers when compared to those with limited pulmonary form. X-ray Stage I and erythema nodosum were less frequent in extrapulmonary disease. Serum levels of CRP, SACE, sIL-2R and neopterin and BAL cellular profile did not differ between both phenotypes. We observed lower platelets, FEV1, VC, and BAL CD19+ in females with extrapulmonary involvement than in those with pulmonary disease. CONCLUSION: Affected lymph nodes, skin and hypercalciuria were the most common in sarcoidosis patients with extrapulmonary involvement. Pulmonary sarcoidosis did not differ in clinical and routine laboratory parameters from pulmonary plus extrapulmonary sarcoidosis. Observation of low platelets, VC, FEV1 and BAL CD19+ in females with extrapulmonary sarcoidosis needs further verification in larger cohort.

Histone deacetylase activity modulates alternative splicing.

There is increasing evidence to suggest that splicing decisions are largely made when the nascent RNA is still associated with chromatin. Here we demonstrate that activity of histone deacetylases (HDACs) influences splice site selection. Using splicing-sensitive microarrays, we identified ∼700 genes whose splicing was altered after HDAC inhibition. We provided evidence that HDAC inhibition induced histone H4 acetylation and increased RNA Polymerase II (Pol II) processivity along an alternatively spliced element. In addition, HDAC inhibition reduced co-transcriptional association of the splicing regulator SRp40 with the target fibronectin exon. We further showed that the depletion of HDAC1 had similar effect on fibronectin alternative splicing as global HDAC inhibition. Importantly, this effect was reversed upon expression of mouse HDAC1 but not a catalytically inactive mutant. These results provide a molecular insight into a complex modulation of splicing by HDACs and chromatin modifications.