Non‑canonical Wnt signaling contributes to ventilator‑induced lung injury through upregulation of WISP1 expression

TNIK influence the effects of antipsychotics on Wnt/β-catenin signaling pathway

RationaleTraf2- and Nck-interacting kinase (TNIK), a member of germinal center kinase (GCK) family, has been implicated as a risk factor in schizophrenia and bipolar disorder as well as the action of antipsychotics. TNIK is an essential activator of Wnt/β-catenin signaling pathway which has been identified involved in the mechanism underlying the effects of antipsychotics. Thus, the effects of TNIK on antipsychotics may be achieved by influencing Wnt/β-catenin signaling pathway proteins.Objectives and methodsIn the current study, the effects of up- or downregulated TNIK on β-catenin, T-cell factor 4 (TCF-4), glycogen synthase kinase-3β (GSK3β), and phosphorylated GSK3β (p-GSK3β) were examined in the human glioma U251 cells. Then, we observed the effects of antipsychotics (clozapine and risperidone) on the above proteins and evaluated the role of differentially expressed TNIK on antipsychotic-treated cell groups.ResultsThe result showed that clozapine treatment decreased β-catenin and TCF-4 levels in U251 cells, and risperidone had the similar effects on β-catenin and p-GSK3β. The downregulated TNIK using siRNA impeded the regulation of antipsychotics on Wnt pathway proteins via increasing the expression levels of TCF-4, β-catenin, or p-GSK3β, whereas the upregulated TNIK made no significant change.ConclusionsThe influence of TNIK on the effects of antipsychotics may be partly through Wnt/β-catenin signaling pathway.

Ventilator-induced lung-injury in mouse models: Is there a trap?

Ventilator-induced lung injury (VILI) is a serious acute injury to the lung tissue that can develop during mechanical ventilation of patients. Due to the mechanical strain of ventilation, damage can occur in the bronchiolar and alveolar epithelium resulting in a cascade of events that may be fatal to the patients. Patients requiring mechanical ventilation are often critically ill, which limits the possibility of obtaining patient samples, making VILI research challenging. In vitro models are very important for VILI research, but the complexity of the cellular interactions in multi-organ animals, necessitates in vivo studies where the mouse model is a common choice. However, the settings and duration of ventilation used to create VILI in mice vary greatly, causing uncertainty in interpretation and comparison of results. This review examines approaches to induce VILI in mouse models for the last 10 years, to our best knowledge, summarizing methods and key parameters presented across the studies. The results imply that a more standardized approach is warranted.

Mining the key genes for ventilator-induced lung injury using co-expression network analysis

Mechanical ventilation is extensively adopted in general anesthesia and respiratory failure management, but it can also induce ventilator-induced lung injury (VILI). Therefore, it is of great urgency to explore the mechanisms involved in the VILI pathogenesis, which might contribute to its future prevention and treatment. Four microarray datasets from the GEO database were selected in our investigation, and were subjected to the Weighted Gene Co-Expression Network Analysis (WGCNA) to identify the VILI-correlated gene modules. The limma package in R software was used to identify the differentially expressed genes (DEGs) between the VILI and control groups. WGCNA was constructed by merging the GSE9314, GSE9368, GSE11434 and GSE11662 datasets. A total of 49 co-expression network modules were determined as associated with VILI. The intersected genes between hub genes screened from DEGs for VILI and those identified using WGCNA were as follows: Tlr2, Hmox1, Serpine1, Mmp9, Il6, Il1b, Ptgs2, Fos and Atf3, which were determined to be key genes for VILI. Those key genes were validated by GSE86229 and quantitative PCR (qPCR) experiment to have significantly statistical difference in their expression between the VILI and control groups. In a nutshell, nine key genes with expression differences in VILI were screened by WGCNA by integrating multiple datasets.

Characterization of TGF-β by Induced Oxidative Stress in Human Trabecular Meshwork Cells

Oxidative stress generated by reactive oxygen species (ROS) plays a critical role in the pathomechanism of glaucoma, which is a multifactorial blinding disease that may cause irreversible damage within human trabecular meshwork cells (HTMCs). It is known that the transforming growth factor-β (TGF-β) signaling pathway is an important component of oxidative stress-induced damage related to extracellular matrix (ECM) fibrosis and activates cell antioxidative mechanisms. To elucidate the dual potential roles and regulatory mechanisms of TGF-β in effects on HTMCs, we established an in vitro oxidative model using hydrogen peroxide (H₂O₂) and further focused on TGF-β-related oxidative stress pathways and the related signal transduction. Via a series of cell functional qualitative analyses to detect related protein level alterations and cell fibrosis status, we illustrated the role of TGF-β1 and TGF-β2 in oxidative stress-induced injury by shTGF-β1 and shTGF-β2 knockdown or added recombinant human TGF-β1 protein (rhTGF-β1). The results of protein level showed that p38 MAPK, TGF-β, and its related SMAD family were activated after H₂O₂ stimulation. Cell functional assays showed that HTMCs with H₂O₂ exposure duration had a more irregular actin architecture compared to normal TM cells. Data with rhTGF-β1 (1 ng/mL) pretreatment reduced the cell apoptosis rate and amount of reactive oxygen species (ROS), while it also enhanced survival. Furthermore, TGF-β1 and TGF-β2 in terms of antioxidant signaling were related to the activation of collagen I and laminin, which are fibrosis-response proteins. Succinctly, our study demonstrated that low concentrations of TGF-β1 (1 ng/mL) preserves HTMCs from free radical-mediated injury by p-p38 MAPK level and p-AKT signaling balance, presenting a signaling transduction mechanism of TGF-β1 in HTMC oxidative stress-related therapies.