Cigarette smoking is a major pathogenic factor in lung cancer. Macrophages play an important role in host defense and adaptive immunity. These cells display diverse phenotypes for performing different functions. M2 type macrophages usually exhibit immunosuppressive and tumor-promoting characteristics. Although macrophage polarization toward the M2 phenotype has been observed in the lungs of cigarette smokers, the molecular basis of the process remains unclear. In this study, we evaluated the possible mechanisms for the polarization of mouse macrophages that are induced by cigarette smoking (CS) or cigarette smoke extract (CSE). The results showed that exposure to CSE suppressed the production of reactive oxygen species (ROS) and nitric oxide (NO) and down-regulated the phagocytic ability of Ana-1 cells. The CD163 expressions on the surface of macrophages from different sources were significantly increased in in vivo and in vitro studies. The M1 macrophage cytokines TNF-α, IL-12p40 and enzyme iNOS decreased in the culture supernatant, and their mRNA levels decreased depending on the time and concentration of CSE. In contrast, the M2 phenotype macrophage cytokines IL-10, IL-6, TGF-β1 and TGF-β2 were up-regulated. Moreover, phosphorylation of JAK2 and STAT3 was observed after the Ana-1 cells were treated with CSE. In addition, pretreating the Ana-1 cells with the STAT3 phosphorylation inhibitor WP1066 inhibited the CSE-induced CD163 expression, increased the mRNA level of IL-10 and significantly decreased the mRNA level of IL-12. In conclusion, we demonstrated that the M2 polarization of macrophages induced by CS could be mediated through JAK2/STAT3 pathway activation. 相似文献
Cadmium (Cd), a toxic environmental contaminant, induces neurodegenerative diseases. Celastrol, a plant‐derived triterpene, has shown neuroprotective effects in various disease models. However, little is known regarding the effect of celastrol on Cd‐induced neurotoxicity. Here, we show that celastrol protected against Cd‐induced apoptotic cell death in neuronal cells. This is supported by the findings that celastrol strikingly attenuated Cd‐induced viability reduction, morphological change, nuclear fragmentation, and condensation, as well as activation of caspase‐3 in neuronal cells. Concurrently, celastrol remarkably blocked Cd‐induced phosphorylation of c‐Jun N‐terminal kinase (JNK), but not extracellular signal‐regulated kinases 1/2 and p38, in neuronal cells. Inhibition of JNK by SP600125 or over‐expression of dominant negative c‐Jun potentiated celastrol protection against Cd‐induced cell death. Furthermore, pre‐treatment with celastrol prevented Cd down‐regulation of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and activation of phosphoinositide 3′‐kinase/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling in neuronal cells. Over‐expression of wild‐type PTEN enhanced celastrol inhibition of Cd‐activated Akt/mTOR signaling and cell death in neuronal cells. The findings indicate that celastrol prevents Cd‐induced neuronal cell death via targeting JNK and PTEN‐Akt/mTOR network. Our results strongly suggest that celastrol may be exploited for the prevention of Cd‐induced neurodegenerative disorders.
Hierarchical Cu2S microspheres wrapped by reduced graphene oxide (RGO) nanosheets are prepared via a one‐step solvothermal process. The amount of graphene oxide used in the synthesis process has a remarkable effect on the features of Cu2S microspheres. Compared to Pt and Cu2S electrodes, RGO‐Cu2S electrodes show better electrocatalytic activity, greater stability, lower charge‐transfer resistance, and higher exchange current density. As expected, RGO‐Cu2S electrodes exhibit superior performance when functioning as counter electrodes in CdS/CdSe quantum dot‐sensitized solar cells (QDSSCs) using a polysulfide electrolyte. A power conversion efficiency up to 3.85% is achieved for the QDSSC employing an optimized RGO‐Cu2S counter electrode, which is higher than those of the QDSSCs featuring Pt (2.14%) and Cu2S (3.39%) counter electrodes. 相似文献
Pursuing the rural idyll for retirement is especially a popular age-old dream for Taiwan people. Farming for health is an emerging trend, which drivers to initiate a green care service based on a combination of agriculture resources and traditional care. The purposes of this study were to assess the feasibility of green care in rural communities and to propose implementation strategies for varied rural area types in Taiwan. This study was conducted with two stags. A feasibility study comprising two aspects of political and environmental feasibilities was assessed in the first stage. The political feasibility was assessed based on social demand and government policies. Accordingly, three alternative models for senior green care participation were proposed, including green occupational therapy (for residents), rural long-stay tourism (for tourists), and agricultural working holiday (for volunteers). The environmental feasibility assessment was conducted in 102 rural communities in northern Taiwan. Five indexes, including the natural environment, rural resources, public facilities, senior care, and community capacity, were used to evaluate the potential of communities for developing green care. The results showed that green care implementing active aging in place in rural areas is feasible. Seventeen communities with plentiful or unique rural resources and high-quality community capacity were recommended as potential communities. In the second stage, a multiple case study was conducted in three communities representing different alternative models of green care. The community leader interviews, on-site investigations, vision forum, and operation workshop were adopted to propose the implementation strategies of green care for three communities, respectively, including human resource, volunteer or tourist management, revenue distribution, and marketing.
Virologica Sinica - The sudden emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) has caused global panic in 2003, and the risk of SARS-CoV outbreak still exists. However, no... 相似文献
Virologica Sinica - SARS-CoV-2 has become a global pandemic threatening human health and safety. It is urgent to find effective therapeutic agents and targets with the continuous emergence of novel... 相似文献