Harmful effects of true-to-life nanoplastics derived from PET water bottles in human alveolar macrophages.

The increasing presence of secondary micro/nanoplastics (MNPLs) in the environment requires knowing if they represent a real health concern. To such end, an important point is to test representative MNPLs such as the denominated true-to-life MNPLs, resulting from the degradation of plastic goods in lab conditions. In this study, we have used polyethylene terephthalate (PET) NPLs resulting from the degradation of PET water bottles. Since inhalation is an important exposure route to environmental MNPLS, we have used mouse alveolar macrophages (MH-S) as a target cell, and the study focused only on the cells that have internalized them. This type of approach is novel as it may capture the realistic adverse effects of PETNPLs only in the internalized cells, thereby mitigating any biases while assessing the risk of these MNPLs. Furthermore, the study utilized a set of biomarkers including intracellular reactive oxygen species (ROS) levels, variations on the mitochondrial membrane potential values, and the macrophage polarization to M1 (pro-inflammatory response) and M2 (anti-proinflammatory response) as possible cellular effects due to PETNPLs in only the cells that internalized PETNPLs. After exposures lasting for 3 and 24 h to a range of concentrations (0, 25, 50, and 100 µg/mL) the results indicate that no toxicity was induced despite the 100% internalization observed at the highest concentration. Significant intracellular levels of ROS were observed, mainly at exposures lasting for 24 h, in an indirect concentration-effect relationship. Interestingly, a reduction in the mitochondrial membrane potential was observed, but only at exposures lasting for 24 h, but without a clear concentration-effect relationship. Finally, PETNPL exposure shows a significant polarization from M0 to M1 and M2 subtypes. Polarization to M1 (pro-inflammatory stage) was more marked and occurred at both exposure times. Polarization to M2 (anti-inflammatory stage) was only observed after exposures lasting for 24 h. Due to the relevance of the described biomarkers, our results underscore the need for further research, to better understand the health implications associated with MNPL exposure.

SZ168 treats LPS-induced acute lung injury by inhibiting the activation of NF-κB and MAPKs pathways.

BACKGROUND: This study aimed to elucidate the effect and underlying molecular mechanisms of SZ168 (Podoplanin (PDPN) monoclonal antibody) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) mice and LPS-induced MH-S cells. METHODS: The survival rate was calculated by recording the death of mice in each group. Enzyme linked immunosorbent assay (ELISA) was used to detect the levels of interleukin (IL)- 6 and tumor necrosis factor-alpha (TNF-α) in blood and bronchoalveolar lavage fluid (BALF) of mice. Hematoxylin-eosin (H&E) staining were performed to evaluate the pathological changes in pulmonary tissues. Additionally, the phagocytosis of cells was tested by flow cytometry, and the expression levels of caveolin-1 (CAV-1) and Occludin proteins in lung tissue and the expression of nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathway-related proteins in MH-S cells were determined by western blot. RESULTS: SZ168 significantly improved the survival rate of ALI mice. Briefly speaking, SZ168 protected pulmonary vascular permeability, reduced the level of pro-inflammatory cytokines, improved the pathological changes of lung tissue, reduced the infiltration of inflammatory cells, increased CAV-1 and Occludin protein expression, and then effectively relieved lung injury. In addition, SZ168 could significantly reduce the phagocytic ability of LPS-induced MH-S cells and inhibit the expression of hospho-extracellular regulated protein kinases (p-ERK), Phospho-Jun N-terminal kinase (p-JNK), Phospho-NF-κB p65 (p-p65) and Phospho-IkappaB-alpha (p-IκBα). CONCLUSION: SZ168 can treat ALI by inhibiting the activation of NF-κB and MAPK signaling pathways and restoring tight junction protein expression.

Effect of cold stimulation on phenotype of alveolar macrophages in mice / 中国生物制品学杂志

@#Objective To investigate the effect of cold stimulation on the phenotype of alveolar macrophages(MH-S cells) in mice. Methods MH-S cells were cultured at 37 ℃ for 24 h,and cold stimulated at 36,34 and 32 ℃ for 0,0. 5,1,3,6,9 and 12 h respectively. The mRNA transcription levels of interleukin-1β(IL-1β) and interleukin-10(IL-10) genes in MH-S cells were detected by qRT-PCR. MH-S cells were cultured at 37 ℃ for 24 h,and cold stimulated at 34 ℃ for 0. 5 h,which were detected for the mRNA transcription levels of tumor necrosis factor-α(TNF-α),inducible nitric oxide synthase(iNOS)and Arginase1(Arg1)genes by qRT-PCR(MH-S cells with 0 h cold stimulation as control),detected for the expression of iNOS and Arg1 by immunofluorescence assay(MH-S cells cultured at 37 ℃ for 0. 5 h as negative control)and detected for the expression levels of iNOS,TNF-α and nuclear factor-kappa B(NF-κB)by Western blot(MH-S cells cultured at 37 ℃ for 0. 5 h as negative control). Results The mRNA transcription levels of IL-1β and IL-10 genes in MH-S cells were the highest when the cells were cultured at 34 ℃ for 0. 5 h,therefore,the cold stimulation model of MH-S cells was established under this condition. Compared with the cells cultured for 0 h,the mRNA transcription levels of iNOS,TNF-α and Arg1genes in MH-S cells cultured at 34 ℃ for 0. 5 h increased significantly(t = 3. 733,12. 190 and 6. 793,respectively,each P < 0. 05). Compared with the negative control group,the fluorescence expression intensity of iNOS and Arg1 in MH-S cells in the stimulation group increased,especially iNOS,the expression levels of iNOS and TNF-α proteins increased with no significant difference(t = 0. 675 and 1. 514,respectively,each P > 0. 05),and the expression level of NF-κB increased significantly(t = 3. 092,P < 0. 05). Conclusion Cold stimulation at 34 ℃ for 0. 5 h can increase the expression of inflammatory factors such as IL-1β,IL-10,TNF-α,iNOS,Agr1 and NF-κB in MH-S cells,activate NF-κB signaling pathway in MH-S cells,induce the expression of inflammatory proteins and promote cell activation.

Analogous corticosteroids, 9A and EK100, derived from solid-state-cultured mycelium of Antrodia camphorata inhibit proinflammatory cytokine expression in macrophages.

Antrodia camphorata mycelium is used in traditional Chinese medicine in Taiwan. The wild-type mycelium is rare and expensive, so a solid-state-cultured mycelium of A. camphorata (SCMAC) has been developed. Previous studies have found SCMAC to have anti-inflammatory effects. However, the immunomodulatory effects of SCMAC and of its active phytosterol compounds EK100 and 9A on asthma remain unknown. In this study, BALB/c mice were repeatedly exposed to Dermatogoides pteronyssinus (Der p) at 1-week intervals and were orally administered crude SCMAC extract before the Der p challenge. The mice were sacrificed 72 h after the last challenge to examine the airway remodeling, inflammation, and expression profiles of cytokines and various genes. Then, 30-µg/mL Der p-stimulated MH-S cells with 9A or EK100 were collected for real-time PCR analysis, and the effects of 9A and EK100 on macrophages were evaluated. The crude extract reduced Der p-induced airway hyperresponsiveness, total serum immunoglobulin E levels, and recruitment of inflammatory cells to the bronchoalveolar lavage fluid through cytokine downregulation and Th1/Th2/Th17 response modulation. Additionally, 9A and EK100 inhibited IL-1ß and IL-6 expression in alveolar macrophages. These results indicate that the pharmacologically active compounds in a crude SCMAC extract exert synergistic effects on multiple targets to relieve asthma symptoms.