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Bisphenol A (BPA) can disrupt glucose homeostasis and impair pancreatic islet function; however, the mechanisms behind these effects are poorly understood. Male mice (4 wk old) were treated with BPA (50 or 500 μg/kg/d) for 8 wk. Whole-body glucose homeostasis, pancreatic islet morphology and function, and miR-338-mediated molecular signal transduction analyses were examined. We showed that BPA treatment led to a disruption of glucose tolerance and a compensatory increase of pancreatic islets insulin secretion and pancreatic and duodenal homeobox 1 () expression in mice. Inhibition of Pdx1 reduced glucose-stimulated insulin secretion and ATP production in the islets of BPA-exposed mice. Based on primary pancreatic islets, we also confirmed that miR-338 regulated Pdx1 and thus contributed to BPA-induced insulin secretory dysfunction from compensation to decompensation. Short-term BPA exposure downregulated miR-338 through activation of G-protein-coupled estrogen receptor 1 (Gpr30), whereas long-term BPA exposure upregulated miR-338 through suppression of glucagon-like peptide 1 receptor (Glp1r). Taken together, our results reveal a molecular mechanism, whereby BPA regulates Gpr30/Glp1r to mediate the expression of miR-338, which acts to control Pdx1-dependent insulin secretion. The Gpr30/Glp1r-miR-338-Pdx1 axis should be represented as a novel mechanism by which BPA induces insulin secretory dysfunction in pancreatic islets.-Wei, J., Ding, D., Wang, T., Liu, Q., Lin, Y. MiR-338 controls BPA-triggered pancreatic islet insulin secretory dysfunction from compensation to decompensation by targeting Pdx-1.

Purpose: Lung cancer is one of the most prevailing human cancers worldwide. Emerging evidence implies that long non-coding RNA nicotinamide nucleotide transhydrogenaseantisense RNA1 (NNT-AS1) is implicated in the tumorigenesis of lung cancer. Herein, we aimed to expose the impact of NNT-AS1 on the drug resistance of lung cancer. Methods: Levels of NNT-AS1, microRNA (miR)-1236-3p and autophagy-related gene 7 (ATG7) were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) assay. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was implemented to detect cell proliferation and the half maximal inhibitory concentration (IC 50 ) of cisplatin (DDP) in vitro. Moreover, flow cytometry was performed to assess cell apoptosis. Cell migration and invasion were examined utilizing transwell assay in lung cancer cells. Besides, levels of ATG7 and cell behavior-related proteins were determined via Western blot. Dual-luciferase reporter assay was administrated to identify the interaction between miR-1236-3p and NNT-AS1 or ATG7. The biological role of NNT-AS1 in DDP resistance of lung cancer was examined by xenograft tumor model in vivo. Results: NNT-AS1 and ATG7 were upregulated, whereas miR-1236-3p was curbed in lung cancer tissues and in with or without DDP-resistant cell lines. NNT-AS1 detection significantly constrained cell growth, metastasis, and the IC 50 of DDP in A549/DDP and H522/ DDP cells. Interestingly, the influence of miR-1236-3p mimic on DDP resistance was overturned via NNT-AS1 upregulation in vitro. Reintroduction of miR-1236-3p inhibitor relieved the effect of ATG7 silencing on DDP sensitivity in A549/DDP and H522/DDP cells. Importantly, NNT-AS1 was a sponge of miR-1236-3p to separate ATG7. Besides, NNT-AS1 silencing enhanced DDP sensitivity of lung cancer in vivo. Conclusion: NNT-AS1/miR-1236-3p/ATG7 axis regulated DDP resistance in lung cancer cells and might supply a probable target and prognostic marker in lung cancer treatment.

An air-conditioned coach is an important form of transportation in modern motorized society; as a result, there is an increasing concern of in-vehicle air pollution. In this study, we aimed to identify and quantify the levels of volatile organic compounds (VOCs) and carbonyl compounds (CCs) in air samples collected from the cabins of newly produced, medium- and large-size coaches. Among the identified VOCs and CCs, toluene, ethylbenzene, xylene, formaldehyde, acetaldehyde, acrolein/acetone, and isovaleraldehyde were relatively abundant in the cabins. Time was found to affect the emissions of the contaminants in the coaches. Except for benzaldehyde, valeraldehyde and benzene, the highest in-vehicle concentrations of VOCs and CCs were observed on the 15th day after coming off the assembly line, and the concentrations exhibited an approximately inverted U-shaped pattern as a function of time. Interestingly, this study also showed that the interior temperature of the coaches significantly affected the VOCs emissions from the interior materials, whereas the levels of CCs were mainly influenced by the relative humidity within the coaches. In China, guidelines and regulations for the in-vehicle air quality assessment of the coaches have not yet been issued. The results of this study provide further understanding of the in-vehicle air quality of air-conditioned coaches and can be used in the development of both specific and general rules regarding medium- and large-size coaches.

Exposure to ambient particulate matter (PM) has been linked to the increasing incidence and mortality of lung cancer, but the principal toxic components and molecular mechanism remain to be further elucidated. In this study, human lung adenocarcinoma A549 cells were treated with serial concentrations of water-extracted PM (WE-PM) collected from Beijing, China. Our results showed that exposure to 25 and 50 μg/ml of WE-PM for 48 h significantly suppressed miR-26a to upregulate lin-28 homolog B (LIN28B), and in turn activated interleukin 6 (IL6) and signal transducer and activator of transcription 3 (STAT3) in A549 cells, subsequently contributing to enhanced epithelial-mesenchymal transition and accelerated migration and invasion. In vivo pulmonary colonization assay further indicated that WE-PM enhanced the metastatic ability of A549 cells. In addition, luciferase reporter assay demonstrated that 3' untranslated region of LIN28B was a direct target of miR-26a. Last but not the least, the key toxic contribution of metals in WE-PM was confirmed by the finding that removal of metals through chelation significantly rescued WE-PM-mediated inflammatory, carcinogenic and metastatic responses. Taken together, miR-26a could act as the tumor suppressor in PM-related lung cancer, and PM-bound metals promoted lung cancer cell metastasis through downregulation of miR-26a that directly mediated LIN28B expression.

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