Integrated analysis of gene expression and genomic aberration data in osteosarcoma (OS)

Cytogenetic analyses have revealed that complex karyotypes with numerous and highly variable genomic aberrations including single-nucleotide polymorphisms (SNPs) and copy number variants (CNVs), are observed in most of the conventional osteosarcomas (OSs). Several genome-wide studies have reported that the dysregulated expression of many genes is correlated with genomic aberrations in OS. We first compared OS gene expression in Gene Expression Omnibus (GEO) data sets and genomic aberrations in International Cancer Genome Consortium (ICGC) database to identify differentially expressed genes (DEGs) associated with SNPs or CNVs in OS. Then the function annotation of SNP- or CNV-associated DEGs was performed in terms of gene ontology analysis, pathway analysis and protein-protein interactions (PPIs). Finally, the expression of genes correlated with both SNPs and CNVs were confirmed by quantitative reverse-transcription PCR. Eight publicly available GEO data sets were obtained, and a set of 979 DEGs were identified (472 upregulated and 507 downregulated DEGs). Moreover, we obtained 1039 SNPs mapped in 938 genes, and 583 CNV sites mapped in 2915 genes. Comparing genomic aberrations and DGEs, we found 41 SNP-associated DEGs and 124 CNV-associated DEGs, in which 7 DGEs were associated with both SNPs and CNVs, including WWP1, EXT1, LDHB, C8orf59, PLEKHA5, CCT3 and VWF. The result of function annotation showed that ossification, bone development and skeletal system development were the significantly enriched terms of biological processes for DEGs. PPI network analysis showed that CCT3, COPS3 and WWP1 were the significant hub proteins. We conclude that these genes, including CCT3, COPS3 and WWP1 are candidate driver genes of importance in OS tumorigenesis.

Coronary Artery Disease Associated Transcription Factor TCF21 Regulates Smooth Muscle Precursor Cells that Contribute to the Fibrous Cap

TCF21 is a basic helix-loop-helix transcription factor that has recently been implicated as contributing to susceptibility to coronary heart disease based on genome wide association studies. In order to identify transcriptionally regulated target genes in a major disease relevant cell type, we performed siRNA knockdown of TCF21 in in vitro cultured human coronary artery smooth muscle cells and compared the transcriptome of siTCF21 versus siCONTROL treated cells. The raw (FASTQ) as well as processed (BED) data from 3 technical replicates per treatment has been deposited with Gene Expression Omnibus (GSE44461).

Autonomic dysreflexia during cystolitholapaxy in patients with spinal cord injury

AIM

This study aims to explore the risk factors associated with autonomic dysreflexia (AD) reflex during cystolitholapaxy and increase the awareness of urologists on the dangerous reaction of AD in patients with spinal cord injury (SCI).

METHODS

Data of 89 SCI patients with bladder stone who underwent cystolitholapaxy were retrospectively analyzed. Patients were divided into two groups according to the presence or absence of AD. Risk factors may associated with AD during the endoscopic procedure were analyzed by comparing clinical and operative features between the two groups.

RESULTS

Of the 89 patients, 31 (34.83%) developed AD during the procedure. The patients who developed AD had larger stones (4.58±1.26 cm vs. 3.75±1.15 cm, P<0.01), more stones (2.29±0.86 vs. 1.74±0.81, P<0.01), and greater injury (83.87% vs. 41.38%, above T6, P<0.01) than those who did not develop AD. The patients who developed AD suffered higher irrigation (83.55± 13.05 cm vs. 77.47±10.91 cm, P<0.05) and longer operation time (60.65±17.78 min vs. 49.31±14.31 min, P<0.01) than those who did not develop AD. The AD group also received local anesthetics to a larger extent compared with non-AD group, which more often had spinal anesthesia.

CONCLUSION

The patients who developed AD during the procedure had larger stones, more stone number, injury level more often above T6, higher hydraulic irrigation height, and longer operation time compared with the patients who did not develop AD. Urologists should pay extra care when performing cystolitholapaxy on individuals with these features.

An association analysis between psychophysical characteristics and genome-wide gene expression changes in human adaptation to the extreme climate at the Antarctic Dome Argus

Genome-wide gene expression measurements have enabled comprehensive studies that integrate the changes of gene expression and phenotypic information to uncover their novel associations. Here we reported the association analysis between psychophysical phenotypes and genome-wide gene expression changes in human adaptation to one of the most extreme climates on Earth, the Antarctic Dome Argus. Dome A is the highest ice feature in Antarctica, and may be the coldest, driest and windiest location on earth. It is considered unapproachable due to its hostile environment. In 2007, a Chinese team of 17 male explorers made the expedition to Dome A for scientific investigation. Overall, 133 psychophysical phenotypes were recorded, and genome-wide gene expression profiles from the blood samples of the explorers were measured before their departure and upon their arrival at Dome A. We found that mood disturbances, including tension (anxiety), depression, anger and fatigue, had a strong, positive, linear relationship with the level of a male sex hormone, testosterone, using the Pearson correlation coefficient (PCC) analysis. We also demonstrated that significantly lowest-level Gene Ontology groups in changes of gene expression in blood cells with erythrocyte removal were consistent with the adaptation of the psychophysical characteristics. Interestingly, we discovered a list of genes that were strongly related to significant phenotypes using phenotype and gene expression PCC analysis. Importantly, among the 70 genes that were identified, most were significantly related to mood disturbances, where 42 genes have been reported in the literature mining, suggesting that the other 28 genes were likely novel genes involved in the mood disturbance mechanism. Taken together, our association analysis provides a reliable method to uncover novel genes and mechanisms related to phenotypes, although further studies are needed.

MLK3 promotes melanoma proliferation and invasion and is a target of microRNA-125b

BACKGROUND

Metastatic melanoma is a disease with high mortality and limited therapeutic options. MicroRNAs (miRNAs) can be used to classify melanoma stage.

METHODS

Expression of the miRNA miR-125b and serine/threonine kinase mixed lineage kinase (MLK)3 was assessed in primary malignant melanoma tissues and several melanoma cell lines by quantitative reverse transcription PCR. The effect of MLK3 and miR-125b on cell proliferation was evaluated by MTS assay, and cell invasion was evaluated by Transwell invasion assays. Targeting of MLK3 by miR-125b was evaluated using luciferase reporter assay and western blotting.

RESULTS

We found significantly increased levels of MLK3 in metastatic primary malignant melanomas and melanoma cell lines, with levels being especially high in metastatic lines. To investigate the functional significance of MLK3, we used knockdown MLK3, which was found to suppress cell growth and invasion. Using bioinformatics, we identified MLK3 as one potential target of miR-125b. miRNA transfection and luciferase assay confirmed that MLK3 was regulated by miR-125b at both the transcriptional and translational levels. Cell proliferation and cell invasion was inhibited by overexpression of miR-125b.

CONCLUSIONS

MLK3 is upregulated in metastatic melanoma, and regulates cell proliferation and invasion in melanoma cells. MLK3 is a direct target of miR-125b.

Glial cell line-derived neurotrophic factor promotes proliferation of neuroglioma cells by up-regulation of cyclins PCNA and Ki-67

OBJECTIVE

We wished to test whether glial cell line-derived neurotrophic factor (GDNF) stimulates proliferation of gliomas by up-regulating expression of nuclear cyclins PCNA and Ki37.

MATERIALS AND METHODS

As a model, we tested rat C6 glioma cell line exposed to basal conditions, vehicle control, or exogenous GDNF at different concentrations (0-90 µg/L) or different times (0-72 hours). Cell proliferation was quantified by MTT test, cell cycle by flow cytometry and propidium iodide staining, expression of PCNA and Ki67 by intracellular antibody staining and flow cytometry.

RESULTS

We first observed that cell proliferation was most stimulated by GDNF at concentration of 70 µg/L and incubation time of 48 hours. Using this concentration and incubation time, we next documented that GDNF increased the percentage of cells in the S phase (47.98% vs. 32.57% in basal cells; p < 0.05), while not affecting the percentage of cells in G0/G1 or G2/M phases. Finally, we demonstrated that expression of both PCNA and Ki67 was significantly increased in cells exposed to GDNF.

CONCLUSIONS

We demonstrate that GDNF stimulates proliferation of glioma cells by up-regulating expression of cyclins PCNA and Ki-67.

Shape memory embracing fixator for Vancouver type B and type C periprosthetic femoral fractures

The purpose of this study was to analyze clinical and radiographical results of a group of patients with periprosthetic femoral fractures treated with the shape memory embracing fixator. We retrospectively reviewed twelve patients in whom a total of twelve periprosthetic femoral fractures were treated with the shape memory embracing fixator between August 2004 and February 2013. The patients were 3 men and 9 women (mean age, 69.9 years; range 42-92 years). The average duration of follow-up was 39.3 months (range 4-103 months). In one case, bone grafting was used. Postoperative evaluation was based on radiographs and Harris hip scores. All fractures healed at on average 4.4 months (range: 3 to 6 months) after surgery. None of the patients developed nonunion or malunion during the follow up. And there was no implant failure and no infection during follow up. The average Harris hip score at the final follow-up examination was 84.8 points. Results show that the shape memory embracing fixator is a safe and effective means for Vancouver type B and type C periprosthetic femoral fractures following hip arthroplasty.

Asymmetrical cortical vessel sign on susceptibility-weighted imaging: a novel imaging marker for early neurological deterioration and unfavorable prognosis

BACKGROUND AND PURPOSE

Susceptibility-weighted imaging (SWI) is a high spatial resolution technique that can indirectly demonstrate increased cerebral oxygen extraction. Our aim was to assess whether asymmetric cortical vessel sign (ACVS) on SWI could be associated with early neurological deterioration (END) as well as 90-day unfavorable outcome in patients with acute ischaemic stroke.

MATERIALS AND METHODS

Consecutive patients with acute middle cerebral artery (MCA) territory infarction were prospectively enrolled. ACVS was defined as more and/or larger vessels with greater signal loss than those in the opposite hemisphere on minimum intensity projection of SWI. The neurofunctional fluctuation during acute phase as well as 90-day outcomes were assessed. A National Institutes of Health Stroke Scale increment ≥2 points and ≥4 points despite standard treatment in the first 72 h after admission was defined as END2 and END4, respectively.

RESULTS

In all, 572 patients were finally enrolled. ACVS on SWI was present in 39 (6.8%) subjects. Multivariate analysis indicated that ACVS is an independent predictor for END2 [odds ratio (OR) 4.47, 95% confidence interval (CI) 1.99-10.05) and END4 (OR 4.24, 95% CI 1.94-9.23). Furthermore, ACVS also correlates with 90-day unfavorable outcome defined as a modified Rankin Scale score >1 point (OR 2.93, 95% CI 1.15-7.48). Both positive and negative predictive values of ACVS for END2, END4 and 90-day prognosis were reasonable and both could be slightly enhanced as long as patients with contralateral artery stenosis or occlusion were excluded.

CONCLUSION

In patients with MCA territory acute ischaemic stroke, especially in those without contralateral internal carotid artery/MCA stenosis or occlusion, ACVS might be considered as a neuroimaging predictor for END and unfavorable prognosis.

Chromosome 12p13 variants predict recurrence of ischaemic stroke in a Chinese population

BACKGROUND AND PURPOSE

A recent genome-wide association study identified two genetic variants (rs12425791 and rs11833579) on chromosome 12p13 that confer risk of ischaemic stroke. The purpose of this study was to examine whether these two polymorphisms are associated with stroke onset and prognosis in a Chinese population.

METHODS

rs12425791 and rs11833579 were genotyped using the improved multiple ligase detection reaction in 913 patients with ischaemic stroke. Analyses of genotype association with onset and prognosis outcomes were evaluated by the Kaplan-Meier method, the log-rank test and Cox proportional hazards models.

RESULTS

rs12425791 and rs11833579 were not associated with age of stroke onset (P = 0.786 and 0.340, respectively). However, these two polymorphisms were significantly associated with risk of stroke recurrence, especially for the large-artery atherosclerosis (LAA) subtype, in recessive models [hazard ratio (HR) 2.52; 95% confidence interval (CI) 1.04-6.12 for rs12425791; HR 2.13; 95% CI 1.03-4.40 for rs11833579]. The combined genotype of these two single-nucleotide polymorphisms showed a locus-dosage effect on recurrence of LAA subtype and was an independent prognostic factor for LAA subtype in the final multivariate Cox regression model.

CONCLUSIONS

These findings indicated that rs12425791 and rs11833579 on chromosome 12p13 may be useful biomarkers for predicting the prognosis of patients with the LAA subtype of ischaemic stroke.

Genetic tuning of the novel avian influenza A(H7N9) virus during interspecies transmission, China, 2013

A novel avian influenza A(H7N9) virus causing human infection emerged in February 2013 in China. To elucidate the mechanism of interspecies transmission, we compared the signature amino acids of avian influenza A(H7N9) viruses from human and non-human hosts and analysed the reassortants of 146 influenza A(H7N9) viruses with full genome sequences. We propose a genetic tuning procedure with continuous amino acid substitutions and reassorting that mediates host adaptation and interspecies transmission. When the early influenza A(H7N9) virus, containing ancestor haemagglutinin (HA) and neuraminidase (NA) genes similar to A/Shanghai/05 virus, circulated in waterfowl and transmitted to terrestrial poultry, it acquired an NA stalk deletion at amino acid positions 69 to 73. Then, receptor binding preference was tuned to increase the affinity to human-like receptors through HA G186V and Q226L mutations in terrestrial poultry. Additional mammalian adaptations such as PB2 E627K were selected in humans. The continual reassortation between H7N9 and H9N2 viruses resulted in multiple genotypes for further host adaptation. When we analysed a potential association of mutations and reassortants with clinical outcome, only the PB2 E627K mutation slightly increased the case fatality rate. Genetic tuning may create opportunities for further adaptation of influenza A(H7N9) and its potential to cause a pandemic.

Prognostic significance of low DICER expression regulated by miR-130a in cervical cancer

Dicer is crucial for the maturation of microRNAs (miRNAs) and its dysregulation may contribute to tumor initiation and progression. The study explored the clinical implications of Dicer and its post-transcriptional regulation by microRNAs in cervical cancer. qRT-PCR and immunohistochemistry investigated Dicer mRNA and protein levels in cervical cancer tissues. The relationship between Dicer expression and survival was analyzed. MiRNA target prediction identified miRNAs that might target Dicer. Luciferase reporter and gain- or loss-of-function assays were performed. The results showed that 36.7% of cervical cancer cases showed low expression of Dicer mRNA and 63.3% cases showed high expression. At the protein level, 51% cases showed negative expression and 49% cases showed positive expression. Dicer mRNA and protein expressions were significantly associated with distant metastasis and recurrence in cervical cancer (P=0.002 and P=0.012, respectively). Multivariate Cox analysis indicated that low Dicer expression (P=0.016) and tumor stage (P=0.047) were independent predictors. Among the miRNAs predicted to target Dicer, 10 were detected by RT-PCR; their expressions were significantly higher in cervical cancers with lower Dicer expression than in those with higher Dicer expression and were negatively correlated with Dicer expression level (P<0.05). In vitro experiments demonstrated that miR-130a directly targeted Dicer mRNA to enhance migration and invasion in SiHa cells. Finally, survival analysis indicated that higher expression of miR-130a was significantly associated with poor disease-free survival. Taken together, Dicer expression regulated by miR-130a is an important potential prognostic factor in cervical cancer.

Obese and lean porcine difference of FoxO1 and its regulation through C/EBPβ and PI3K/GSK3β signaling pathway

Forkhead box O 1 (FoxO1) is an important transcription factor implicated in adipogenesis. In this study, we detected the breed differences in FoxO1 between Bamei pigs (an obese breed) and Large White pigs (a lean breed). Compared with Large White pigs, the BW of Bamei pigs was lower (P < 0.01), but back fat thickness, fat percent, and intramuscular fat content were greater (P < 0.01). The levels of FoxO1 mRNA and protein were lower (P < 0.01) in subcutaneous adipose tissue (SAT) of Bamei pigs at 180 d, adipocytes and stromal-vascular fraction extracted from SAT of Bamei pigs at 1 d compared with Large White pigs. Knockdown of FoxO1 increased triglyceride content (P < 0.01) and upregulated the levels of adipocyte fatty-acid binding protein, PPARγ, and CCAAT enhancer-binding protein α (C/EBPα) at 6 d after porcine preadipocytes were induced. Furthermore, the transcriptional regulation of FoxO1 through C/EBPβ during early porcine preadipocyte differentiation and the effect of insulin on phosphoinositide 3 kinase (PI3K)/glycogen synthase kinase 3β (GSK3β) signal pathway by FoxO1 were examined. The results indicated that FoxO1 inhibited transcription activity of C/EBPβ, whereas C/EBPβ did not affect transcription activity of FoxO1. At 6 and 12 h of early differentiation, knockdown of FoxO1 triggered the transcription activity of C/EBPβ. In addition, FoxO1 protein interacted with C/EBPβ protein in porcine adipocytes at 12 h after induction. Under treatment with 100 nM insulin, knockdown or overexpression of FoxO1 mediated PI3K/GSK3β signaling via upregulating or downregulating the levels of GSK3β and its phosphorylation in adipocytes. Taken together, there is low, but detectable, expression of FoxO1 in SAT of obese pigs and FoxO1 inhibited adipogenesis through C/EBPβ and PI3K/GSK3β signaling pathway. These findings provide useful information to further the understanding of the function of FoxO1 in porcine adipogenesis.

Prophylaxis with anti-inhibitor coagulant complex improves health-related quality of life in haemophilia patients with inhibitors: results from FEIBA NF Prophylaxis Study

The Pro-FEIBA study reported health-related quality of life (HRQoL) improved following 6-month of Factor Eight Inhibitor Bypassing Activity (FEIBA) prophylaxis. This study investigates whether 12-month of FEIBA prophylaxis improved HRQoL in haemophilia patients with inhibitors. Thirty-six subjects in a 1-year prospective, randomized, open-label, parallel-design study were randomized to prophylaxis (85 ± 15 U kg(-1) every other day) or on-demand treatment. HRQoL was assessed at screening, 6 and 12-month termination using the EQ-5D, Haem-A-QoL, Haemo-QoL and a general pain visual analog scale (VAS). To evaluate changes, paired t-tests and criteria for minimally important differences were applied. Repeated measures regression tested the association between annualized bleeding rate (ABR) and physical HRQoL. At 6 and 12 months, prophylaxis subjects reported clinically meaningful improvement in EQ-5D index (mean improvement, 0.10 and 0.08, respectively) and both clinically meaningful and statistically significant improvements in EQ-VAS scores (16.9 and 15.7, respectively; P < 0.05) vs. baseline. General pain was significantly reduced during prophylaxis at each follow-up (mean improvement, 20.3 and 23.2, respectively; both P <0.05). At 12 months, prophylaxis subjects achieved significant improvements in Haem-A-QoL Total Score and in four domains: Physical Health, Feeling, View, and Work and School (all P < 0.05). No statistically significant changes, except for Haem-A-QoL Physical Health at 6 months, were observed with on-demand treatment. ABR was decreased by 72.5% with prophylaxis vs. on-demand treatment (P = 0.0003) and reduced ABR was associated with better physical HRQoL (P < 0.05). FEIBA prophylaxis significantly reduced ABR and improved HRQoL in inhibitor patients. Subjects with lower ABR reported better physical HRQoL.

Pittsburgh compound B retention and progression of cognitive status--a meta-analysis

Our aim was to conduct a meta-analysis of longitudinal studies assessing the association between Pittsburgh compound B (PiB) retention and the progression of cognitive status in healthy elderly, in patients with mild cognitive impairment (MCI) and in patients with Alzheimer's disease (AD). PubMed, MEDLINE, Embase and the Cochrane Library up to April 2013 were searched for studies reporting PiB retention at baseline and conversion of clinical status at follow-up, with manual searches of bibliographies of key retrieved articles and relevant reviews. Two independent reviewers extracted data on individual numbers with PiB positive or negative status at baseline and corresponding numbers of patients with cognitive decline at follow-up (conversion from healthy elderly to MCI or AD, or from MCI to AD, or a Mini-Mental State Examination decline >3 for AD patients). Relative risks were pooled using fixed-effects or random-effects models as appropriate. Associations were tested in subgroups representing three different phases of AD. Publication bias was evaluated with funnel plots. Twelve cohort studies including 1275 participants were included with a follow-up period ranging from 1 to 3.8 years. The pooled adjusted relative risks were 3.75 (95% confidence interval 2.76-5.09; P for heterogeneity 0.16; fixed-effects model) for disease progression, 1.73 (0.63-4.75; P for heterogeneity 0.27; fixed-effects model) for AD patients (four studies), 4.03 (2.68-6.07; P for heterogeneity 0.49; fixed-effects model) for MCI patients (eight studies) and 3.67 (2.25-5.99; P for heterogeneity 0.26; fixed-effects model) for disease progression in healthy elderly (six studies). Baseline PiB positive status is associated with a significantly increased risk of cognitive progression in healthy elderly and MCI patients.

Microarray analysis of differentially expressed genes in preeclamptic and normal placental tissues

PURPOSE OF INVESTIGATION

To detect the candidate genes for preeclampsia (PE).

MATERIALS AND METHODS

The gene expression profiles in preeclamptic and normal placental tissues were analyzed using cDNA microarray approach and the altered expression of important genes were further confirmed by real-time RT-PCR (reverse transcription polymerase chain reaction) technique. Total RNA was extracted from placental tissues of three cases with severe PE and from three cases with normal pregnancy. After scanning, differentially expressed genes were detected by software.

RESULTS

In two experiments (the fluorescent labels were exchanged), a total of 111 differentially expressed genes were detected. In placental tissue ofpreeclamptic pregnancy, 68 differentially expressed genes were up-regulated, and 44 differentially expressed genes were down-regulated. Of these genes, 16 highly differentially expressed genes were confirmed by real-time fluorescent quantitative RT-PCR, and the result showed that the ratio of gene expression differences was comparable to that detected by cDNA microarray.

CONCLUSION

The results of bioinformatic analysis showed that encoding products of differentially expressed genes were correlated to infiltration of placenta trophoblastic cells, immunomodulatory factors, pregnancy-associated plasma protein, signal transduction pathway, and cell adhesion. Further studies on the biological function and regulating mechanism of these genes will provide new clues for better understanding of etiology and pathogenesis of PE.

NFAT gene family in inflammation and cancer

Calcineurin-NFAT signaling is critical for numerous aspects of vertebrate function during and after embryonic development. Initially discovered in T cells, the NFAT gene family, consisting of five members, regulates immune system, inflammatory response, angiogenesis, cardiac valve formation, myocardial development, axonal guidance, skeletal muscle development, bone homeostasis, development and metastasis of cancer, and many other biological processes. In this review we will focus on the NFAT literature relevant to the two closely related pathological systems: inflammation and cancer.

Construction of ureteral grafts by seeding bone marrow mesenchymal stem cells and smooth muscle cells into bladder acellular matrix

BACKGROUND

Congenital or acquired abnormalities may cause an ureteral injury or defect. The main methods to reconstruct a long ureter often cause serious complications. In this study, we sought to construct a tissue-engineered graft by seeding bone marrow mesenchymal stem cells (MSCs) and smooth muscle cells (SMCs) into a bladder acellular matrix (BAM) for ureteral reconstruction.

METHODS

Isolated, proliferated, and in vitro identified rabbit bone marrow MSCs and SMCs were seeded into BAM as the experimental group. Grafts only seeding SMCs were the control group. Cell-seeded grafts were used to construct tissue-engineered tubular grafts (TETG) for transplantation into the rabbit's omentum for 2 weeks before ureteral reconstruction. Evolutionary histology was performed at 2, 4, 8, and 16 weeks postoperatively. Renal function and ureteral obstruction were evaluated using intravenous urography at 16 weeks.

RESULTS

Flow cytometry demonstrated bone marrow MSCs to express CD29, CD44, CD90, but not CD34. Histological examination revealed consistent regeneration of TETG urothelium in the experimental group. At 8 and 16 weeks after TETG grafting in vivo, multilayer urothelium covered the entire lumen with visible neovascularization within the center. Organized smooth muscle bundles were observed. Intravenous urography demonstrated no ureteral stricture or hydronephrosis. The 5 rabbits were dead within 4 weeks postoperatively. Autopsy showed scar formation inside the graft with severe hydronephrosis.

CONCLUSION

We successfully constructed a TETG by seeding bone marrow MSCs and SMCs into BAM for ureteral reconstruction. Thus bone marrow MSCs can potentially promote urothelial regeneration to achieve a tissue-engineered ureter.

AQP1 expression alterations affect morphology and water transport in Schwann cells and hypoxia-induced up-regulation of AQP1 occurs in a HIF-1α-dependent manner

Aquaporin-1 (AQP1) is the principle water channel in the peripheral nervous system (PNS) and is specifically localized to Schwann cells in the PNS. However, the pathophysiological role of AQP1 in peripheral nerves is poorly understood. Here, we utilized RNA interference by lentiviral transduction to specifically down-regulate AQP1 expression and a lentiviral overexpression protocol to up-regulate AQP1 expression, in primary Schwann cell cultures. AQP1 gene silencing resulted in a cell shrinkage phenotype, while AQP1 gene overexpression caused a cell swelling phenotype, as validated by cell volume determinations. Secondly, we utilized an in vitro hypoxia model in Schwann cells to mimic in vivo facial nerve injury. We demonstrated that AQP1 expression was induced within 8h following hypoxia injury in vitro, and that AQP1 knockdown (KD) caused the cells to resist edema following hypoxia. Finally, we investigated the hypoxic regulation of the AQP1 gene, as well as the involvement of Hypoxia-inducible factor-1α (HIF-1α) in AQP1 modulation and we found that KD of HIF-1α decreased hypoxia-dependent induction of endogenous AQP1 expression at both the mRNA and protein levels. Taken together, these results indicate that (1) AQP1 is an important factor responsible for the fast water transport of cultured Schwann cells and is involved in cell plasticity; (2) AQP1 alterations may be a primary factor in hypoxia-induced peripheral nerve edema; (3) HIF-1α participates in the hypoxic induction of the AQP1 gene; (4) AQP1 inhibition might provide a new therapeutic alternative for the treatment of some forms of peripheral nerve edema.

Low-Dose Azithromycin Attenuates OVA-Induced Airway Remodeling and Inflammation via Down-Regulating TGF-βl Expression in RAT

Asthma is characteristic with chronic airway inflammation and remodeling. Azithromycin (AZM), the 15-member macrolide, is known to present an anti-inflammatory effect and is increasingly being used in the treatment of chronic inflammatory pulmonary diseases. We hypothesize that low-dose azithromycin can inhibit allergen-induced airway remodeling except allergic airway inflammation in rat model. Male SD rats underwent intraperitoneal ovalbumin sensitization on days 1 and 6 followed by an intranasal challenge on day 7–13. On day 14, airway inflammation and remodeling were assessed by quantifying leukocytes in the airway, expression of multiple inflammatory mediators in BALF, histological examination in lung and TGF-β1 mRNA and protein levels by qRT-PCR, immunohistochemistry and Western blotting. Treatment with low-dose azithromycin at the dose of 25 mg/kg significantly reduced ovalbumin-dependent airway inflammation, including accumulation of neutrophils, lymphocytes and eosinophils, secretion of IL-2, IL-4, IL-13 and TNF-α. Moreover, airway remodeling was significantly abrogated by azithromycin in this model. The mucus cell hyperplasia, thickening of the peribronchial smooth muscle layer, secretion of ET-1, IL-2, IL-4, IL-13 and TNF-α, and increasing mRNA and protein expressions of TGF-β1 in lung tissue were all significantly decreased in azithromycin-treated rats. These findings demonstrate the protective effect of low-dose azithromycin on allergic airway remodeling in rat and suggest low-dose azithromycin may have beneficial effects in treating allergic airway inflammation.