Purpose Particulate matter (PM) has been implicated as a risk factor for airway injury. However, the molecular mechanisms remain largely unclear. The goal of this study was to determine whether sirtuin1 (SIRT1), an anti-inflammatory and antiaging protein, protects against PM-induced airway inflammation. Methods The effect of SIRT1 on PM-induced airway inflammation was assessed by using in vivo models of airway inflammation induced by PM and in vitro culture of human bronchial epithelial (HBE) cells exposed to PM, resveratrol (SIRT1 activator), or both. Results PM-stimulated HBE cells showed a significant decrease in SIRT1 but a notable increase in inflammatory cytokines. SIRT1 gene silencing further enhanced PM-induced expression of inflammatory cytokines. In contrast, resveratrol, a SIRT1 activator, reduced the expression of these cytokines compared with the control cells. In vivo, SIRT1 expression was significantly decreased in lung tissues of PM-exposed mice. Interestingly, resveratrol treatment reversed the enhanced total cells, neutrophils and inflammatory cytokines in PM-induced mice. Moreover, SIRT1 mediated PM-induced inflammatory cytokines expression at least partly through MAPK pathways. Conclusion These findings suggest that SIRT1 is involved in the pathogenesis of PM-induced airway inflammation and activation of SIRT1 could prevent airway disorders or disease exacerbations induced by airborne particulate pollution.

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Sirtuin 1 (SIRT1) is a class III histone deacetylase that exerts an anti-inflammatory effect in airway diseases. Activated macrophages play an important role in asthma. However, the roles of SIRT1 on allergic airway inflammation in macrophages remain largely unexplored. In this study, we aimed to determine the roles of SIRT1 on allergic airway inflammation in macrophages. The effect of myeloid-specific SIRT1 deletion (Sirt1 fl/fl -LysMcre) on airway inflammation was assessed by using in vivo models of asthma following allergen exposure and in vitro culture of primary bone marrow-derived macrophages (BMDMs) exposed to house dust mite (HDM). We observed that Sirt1 fl/fl -LysMcre mice substantially enhanced airway inflammation and mucus production in response to allergen exposure. Expression of chemokine ligand (CXCL) 2, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α were reduced in BMDMs with myeloid-specific deletion of Sirt1 after stimulation of HDM. Moreover, SIRT1 suppressed the inflammatory cytokines expression in BMDMs partially via the ERK/p38 MAPK pathways. Our study demonstrated that SIRT1 suppresses the allergic airway inflammation in macrophages, and suggested that activation of SIRT1 in macrophages may represent therapeutic strategy for asthma.

The detection of circularly polarized light (CPL) has aroused wide attention from both the scientific and industrial communities. However, from the optical activity of the chiral layer in the conventional CPL photodetectors, the sign inversion property is difficult to be achieved. As a result, great challenges arise during the preparation of miniaturized and integrated devices for tunable CPL detection applications. Along these lines, in this work, by taking advantage of the CPL-induced chirality characteristics of the achiral poly­(9,9-di-n-hexylfluorene-alt-benzothiadiazole) (F6BT) and the good crystalline and electrical properties of the poly­(3-hexylthiophene) (P3HT) film, an optically programmable CPL photodetector was fabricated. Interestingly, the device exhibited excellent discrimination between left- and right-handed CPL, while the maximum anisotropy factor of responsivity was 0.425. On top of that, the rigorously controlled chirality of the F6BT and the capability to be switched by the handedness of CPL was leveraged to realize the switchable detection of both L-CPL and R-CPL. Furthermore, a CPL photodetector array was fabricated, and the image processing and cryptographic characteristics were demonstrated. The proposed device configuration can find application in various scientific fields, including photonics, emission, conversion, or sensing with CPL but also is anticipated to play a key role for imaging and anticounterfeiting applications.

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