One of the most rapid (less than 4 ms) transmembrane cellular mechanotransduction events involves activation of transient receptor potential vanilloid 4 (TRPV4) ion channels by mechanical forces ...transmitted across cell surface β1 integrin receptors on endothelial cells, and the transmembrane solute carrier family 3 member 2 (herein denoted CD98hc, also known as SLC3A2) protein has been implicated in this response. Here, we show that β1 integrin, CD98hc and TRPV4 all tightly associate and colocalize in focal adhesions where mechanochemical conversion takes place. CD98hc knockdown inhibits TRPV4-mediated calcium influx induced by mechanical forces, but not by chemical activators, thus confirming the mechanospecificity of this signaling response. Molecular analysis reveals that forces applied to β1 integrin must be transmitted from its cytoplasmic C terminus via the CD98hc cytoplasmic tail to the ankyrin repeat domain of TRPV4 in order to produce ultrarapid, force-induced channel activation within the focal adhesion.
Smoking represents a major risk factor for chronic obstructive pulmonary disease (COPD), but it is difficult to characterize smoke-induced injury responses under physiological breathing conditions in ...humans due to patient-to-patient variability. Here, we show that a small airway-on-a-chip device lined by living human bronchiolar epithelium from normal or COPD patients can be connected to an instrument that “breathes” whole cigarette smoke in and out of the chips to study smoke-induced pathophysiology in vitro. This technology enables true matched comparisons of biological responses by culturing cells from the same individual with or without smoke exposure. These studies led to identification of ciliary micropathologies, COPD-specific molecular signatures, and epithelial responses to smoke generated by electronic cigarettes. The smoking airway-on-a-chip represents a tool to study normal and disease-specific responses of the human lung to inhaled smoke across molecular, cellular and tissue-level responses in an organ-relevant context.
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•Smoking lung airway chip recapitulated clinical oxidative stress molecular profiles•New smoke-induced ciliary micropathologies were identified•This technology supported study of potential toxic effects of electronic cigarettes•COPD-specific responses were reproduced in vitro and novel biomarkers were identified
Benam et al. describe a microengineered in vitro model system that permits analysis of the effects of whole smoke, from both conventional tobacco and electronic cigarettes, delivered under physiologically relevant flow conditions that mimic breathing on the pathophysiology of differentiated human mucociliated bronchiolar epithelium cultured in a microfluidic small airway-on-a-chip.
Podocytes form the outer part of the glomerular filter, where they have to withstand enormous transcapillary filtration forces driving glomerular filtration. Detachment of podocytes from the ...glomerular basement membrane precedes most glomerular diseases. However, little is known about the regulation of podocyte adhesion in vivo. Thus, we systematically screened for podocyte-specific focal adhesome (FA) components, using genetic reporter models in combination with iTRAQ-based mass spectrometry. This approach led to the identification of FERM domain protein EPB41L5 as a highly enriched podocyte-specific FA component in vivo. Genetic deletion of Epb41l5 resulted in severe proteinuria, detachment of podocytes, and development of focal segmental glomerulosclerosis. Remarkably, by binding and recruiting the RhoGEF ARGHEF18 to the leading edge, EPB41L5 directly controls actomyosin contractility and subsequent maturation of focal adhesions, cell spreading, and migration. Furthermore, EPB41L5 controls matrix-dependent outside-in signaling by regulating the focal adhesome composition. Thus, by linking extracellular matrix sensing and signaling, focal adhesion maturation, and actomyosin activation EPB41L5 ensures the mechanical stability required for podocytes at the kidney filtration barrier. Finally, a diminution of EPB41L5-dependent signaling programs appears to be a common theme of podocyte disease, and therefore offers unexpected interventional therapeutic strategies to prevent podocyte loss and kidney disease progression.
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model of the human kidney glomerulus - the major site of blood filtration - could facilitate drug discovery and illuminate kidney-disease mechanisms. Microfluidic organ-on-a-chip technology has ...been used to model the human proximal tubule, yet a kidney-glomerulus-on-a-chip has not been possible because of the lack of functional human podocytes - the cells that regulate selective permeability in the glomerulus. Here, we demonstrate an efficient (> 90%) and chemically defined method for directing the differentiation of human induced pluripotent stem (hiPS) cells into podocytes that express markers of the mature phenotype (nephrin+, WT1+, podocin+, Pax2-) and that exhibit primary and secondary foot processes. We also show that the hiPS-cell-derived podocytes produce glomerular basement-membrane collagen and recapitulate the natural tissue/tissue interface of the glomerulus, as well as the differential clearance of albumin and inulin, when co-cultured with human glomerular endothelial cells in an organ-on-a-chip microfluidic device. The glomerulus-on-a-chip also mimics adriamycin-induced albuminuria and podocyte injury. This
model of human glomerular function with mature human podocytes may facilitate drug development and personalized-medicine applications.
The acute respiratory distress syndrome (ARDS), a devastating lung disease that has no cure, is exacerbated by life-supportive mechanical ventilation that worsens lung edema and inflammation through ...the syndrome of ventilator-induced lung injury. Recently, the membrane ion channel transient receptor potential vanilloid 4 (TRPV4) on alveolar macrophages was shown to mediate murine lung vascular permeability induced by high-pressure mechanical ventilation. The objective of this study was to determine whether inhalation of nanoparticles (NPs) containing the TRPV4 inhibitor ruthenium red (RR) prevents ventilator-induced lung edema in mice. Poly-lactic-co-glycolic acid NPs containing RR were evaluated in vitro for their ability to block TRPV4-mediated calcium signaling in alveolar macrophages and capillary endothelial cells. Lungs from adult C57BL6 mice treated with nebulized NPs were then used in ex vivo ventilation perfusion experiments to assess the ability of the NPs to prevent high-pressure mechanical ventilation-induced lung edema. Poly-lactic-co-glycolic acid NPs (300 nm) released RR for 150 hours in vitro, and blocked TRPV4-mediated calcium signaling in cells up to 7 days after phagocytosis. Inhaled NPs deposited in alveoli of spontaneously breathing mice were rapidly phagocytosed by alveolar macrophages, and blocked increased vascular permeability from high-pressure mechanical ventilation for 72 hours in ex vivo ventilation perfusion experiments. These data offer proof of principle that inhalation of NPs containing a TRPV4 inhibitor prevents ventilator damage for several days, and imply that this novel drug delivery strategy could be used to target alveolar macrophages in patients at risk of ventilator-induced lung injury before initiating mechanical ventilation.
Bone metastases are frequently observed in advanced cancer, and bone modifying agents are used to prevent or treat skeletal-related events. Zoledronic acid is contraindicated in patients with severe ...renal impairment (Ccr < 30 mL/min), but it is not completely known whether denosumab can be used in them. We aimed to determine the association between renal function and hypocalcemia development during denosumab treatment.
We included patients with solid cancer and bone metastases who started denosumab treatment between April 2017 and March 2019. They were classified into four groups based on creatinine clearance (Ccr; mL/min): normal (Ccr ≥ 80), mild (50 ≤ Ccr ˂80), moderate (30 ≤ Ccr ˂50), and severe (Ccr ˂30). Hypocalcemia was evaluated using the Common Terminology Criteria for Adverse Events (v5.0) based on the albumin-adjusted serum calcium levels; its incidence (stratified by renal function) and risk factors were investigated using a Chi-square test and logistic regression analysis.
Of 524 patients (age: 69 ± 11 years; 303 men), 153 had a normal renal function and 222, 117, and 32 had mild, moderate, and severe renal dysfunction. The albumin-adjusted serum calcium level was higher than the measured (total) calcium level in most patients. The incidence of grade ≥ 1 hypocalcemia was 32.0% in the normal group and 37.4%, 29.9%, and 62.5% in the mild, moderate, and severe renal dysfunction groups, respectively. It was, therefore, higher in the severe renal dysfunction groups than in the normal group (P = 0.002). The incidence of grade ≥ 3 hypocalcemia did not differ significantly among the groups. Pre-treatment low serum calcium levels and severe renal dysfunction were risk factors for hypocalcemia.
Evaluating denosumab-induced hypocalcemia required albumin adjustment, and its incidence was high among patients with severe renal dysfunction. Reduced serum calcium levels and severely impaired renal function were associated with an elevated hypocalcemia risk.
Objectives
This study examined the effectiveness of a newly developed work–family life support program on the work–family interface and mental health indicators among Japanese dual‐earner couples ...with a preschool child(/ren) using a randomized controlled trial with a waitlist.
Methods
Participants who met the inclusion criteria were randomly allocated to the intervention or the control groups (n = 79 and n = 85, respectively). The program comprised two 3‐h sessions with a 1‐month interval between them and provided comprehensive skills by including self‐management, couple management, and parenting management components. The program sessions were conducted on weekends in a community center room with 3–10 participants. Outcomes were assessed at baseline, 1‐month, and 3‐month follow‐ups. Primary outcomes were work–family balance self‐efficacy (WFBSE), four types of work–family spillovers (i.e., work‐to‐family conflict, family‐to‐work conflict, work‐to‐family facilitation, and family‐to‐work facilitation), psychological distress, and work engagement reported by the participants.
Results
The program had significantly pooled intervention effects on WFBSE (P = .031) and psychological distress (P = .014). The effect sizes (Cohen's d) were small, with values of 0.22 at the 1‐month follow‐up and 0.24 at the 3‐month follow‐up for WFBSE, and −0.36 at the 3‐month follow‐up for psychological distress. However, the program had nonsignificant pooled effects on four types of work–family spillovers and work engagement.
Conclusions
The program effectively increased WFBSE and decreased psychological distress among Japanese dual‐earner couples with a preschool child(/ren).
IFN-alpha have been reported to suppress hepatitis B virus (HBV) cccDNA via APOBEC3 cytidine deaminase activity through interferon signaling. To develop a novel anti-HBV drug for a functional cure, ...we performed in silico screening of the binding compounds fitting the steric structure of the IFN-alpha-binding pocket in IFNAR2. We identified 37 compounds and named them in silico cccDNA modulator (iCDM)-1-37. We found that iCDM-34, a new small molecule with a pyrazole moiety, showed anti-HCV and anti-HBV activities. We measured the anti-HBV activity of iCDM-34 dependent on or independent of entecavir (ETV). iCDM-34 suppressed HBV DNA, pgRNA, HBsAg, and HBeAg, and also clearly exhibited additive inhibitory effects on the suppression of HBV DNA with ETV. We confirmed metabolic stability of iCDM-34 was stable in human liver microsomal fraction. Furthermore, anti-HBV activity in human hepatocyte-chimeric mice revealed that iCDM-34 was not effective as a single reagent, but when combined with ETV, it suppressed HBV DNA compared to ETV alone. Phosphoproteome and Western blotting analysis showed that iCDM-34 did not activate IFN-signaling. The transcriptome analysis of interferon-stimulated genes revealed no increase in expression, whereas downstream factors of aryl hydrocarbon receptor (AhR) showed increased levels of the expression. CDK1/2 and phospho-SAMHD1 levels decreased under iCDM-34 treatment. In addition, AhR knockdown inhibited anti-HCV activity of iCDM-34 in HCV replicon cells. These results suggest that iCDM-34 decreases the phosphorylation of SAMHD1 through CDK1/2, and suppresses HCV replicon RNA, HBV DNA, and pgRNA formation.
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