scholarly journals Skin damage induced by zinc oxide nanoparticles combined with UVB is mediated by activating cell pyroptosis via the NLRP3 inflammasome–autophagy–exosomal pathway

2022 ◽  
Vol 19 (1) ◽  
Author(s):  
Yu-Ying Chen ◽  
Yu-Hsuan Lee ◽  
Bour-Jr Wang ◽  
Rong-Jane Chen ◽  
Ying-Jan Wang
Keyword(s):  
Zinc Oxide ◽  
Nlrp3 Inflammasome ◽  
Zinc Oxide Nanoparticles ◽  
Skin Toxicity ◽  
Oxide Nanoparticles ◽  
Autophagic Flux ◽  
Skin Thickness ◽  
Inflammasome Activation ◽  
Skin Damage ◽  
Nlrp3 Inflammasome Activation

Abstract Background Zinc oxide nanoparticles (ZnONPs) are widely used nanomaterial in personal cosmetics, such as skin creams and sunscreens, due to their whitening properties and strong UV light absorption. However, the safety issues and the hazards of ZnONPs, which can be taken up by the skin and cause skin toxicity, are still unclear. From a chemoprevention point of view, pterostilbene (PT) has been reported to prevent skin damage effectively by its anti-inflammatory and autophagy inducer effect. This study aims to determine the skin toxicity and the potential mechanisms of UVB and ZnONPs exposure and the preventive effect of PT. Results The co-exposure of UVB and ZnONPs elicit NLRP3 inflammasome activation and pyroptosis in keratinocytes. Furthermore, exposure to both UVB and ZnONPs also disrupts cellular autophagy, which increases cell exosome release. In vivo UVB and ZnONPs exposure triggers skin toxicity, as indicated by increased histological injury, skin thickness and transepidermal water loss. Notably, the NLRP3 inflammasome-mediated pyroptosis are also activated during exposure. Topical application of pterostilbene attenuates NLRP3 inflammasome activation and pyroptosis by decreasing ROS generation and mitochondrial ROS (mtROS) levels. In addition to its antioxidant effect, PT also reversed autophagy abnormalities by restoring normal autophagic flux and decreasing NLRP3 inflammasome-loaded exosome release. Conclusions Our findings reveal that ZnONPs induce skin damage in conjunction with UVB exposure. This process involves an interplay of inflammasomes, pyroptosis, autophagy dysfunction, and exosomes in skin toxicity. PT alleviates skin inflammation by regulating the inflammasome–autophagy–exosome pathway, a finding which could prove valuable when further evaluating ZnONPs effects for cosmetic applications.

scholarly journals Involvement of HO-1 and Autophagy in the Protective Effect of Magnolol in Hepatic Steatosis-Induced NLRP3 Inflammasome Activation In Vivo and In Vitro

Antioxidants ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 924
Author(s):  
Ni-Chun Kuo ◽  
Shieh-Yang Huang ◽  
Chien-Yi Yang ◽  
Hsin-Hsueh Shen ◽  
Yen-Mei Lee
Keyword(s):  
Hepatic Steatosis ◽  
Nlrp3 Inflammasome ◽  
Hepg2 Cells ◽  
Fatty Acid Synthase ◽  
Heme Oxygenase 1 ◽  
Autophagic Flux ◽  
Inflammasome Activation ◽  
Related Factor ◽  
Nlrp3 Inflammasome Activation ◽  
Wide Range

Magnolol (MG) is the main active compound of Magnolia officinalis and exerts a wide range of biological activities. In this study, we investigated the effects of MG using tyloxapol (Tylo)-induced (200 mg/kg, i.p.) hyperlipidemia in rats and palmitic acid (PA)-stimulated (0.3 mM) HepG2 cells. Our results showed that Tylo injection significantly increased plasma levels of triglyceride and cholesterol as well as superoxide anion in the livers, whereas MG pretreatment reversed these changes. MG reduced hepatic lipogenesis by attenuating sterol regulatory element-binding protein-1c (SREBP-1c) and fatty acid synthase (FAS) proteins and Srebp-1, Fas, Acc, and Cd36 mRNA expression as well as upregulated the lipolysis-associated genes Hsl, Mgl, and Atgl. Furthermore, MG reduced plasma interleukin-1β (IL-1β) and protein expression of NLR family pyrin domain-containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), and caspase 1 as well as upregulated nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and induction of heme oxygenase-1 (HO-1) in hepatocytes of Tylo-treated rats. Enhanced autophagic flux by elevation of autophagy related protein 5-12 (ATG5-12), ATG7, Beclin1, and microtubule-associated protein light chain 3 B II (LC3BII)/LC3BI ratio, and reduction of sequestosome-1 (SQSTM1/p62) and phosphorylation of mTOR was observed by MG administration. However, autophagy inhibition with 3-methyladenine (3-MA) in HepG2 cells drastically abrogated the MG-mediated suppression of inflammation and lipid metabolism. In conclusion, MG inhibited hepatic steatosis-induced NLRP3 inflammasome activation through the restoration of autophagy to promote HO-1 signaling capable of ameliorating oxidative stress and inflammatory responses.

scholarly journals A Synthetic Small Molecule F240B Decreases NLRP3 Inflammasome Activation by Autophagy Induction

2020 ◽  
Vol 11 ◽  
Author(s):  
Chun-Hsien Wu ◽  
Chin Heng Gan ◽  
Lan-Hui Li ◽  
Jen-Che Chang ◽  
Shin-Tai Chen ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Membrane Integrity ◽  
Mechanistic Study ◽  
Autophagic Flux ◽  
Inflammasome Activation ◽  
Dependent Manner ◽  
Inflammatory Agent ◽  
Nlrp3 Inflammasome Activation ◽  
Autophagy Induction ◽  
Anti Inflammatory

Conjugated polyenes are a class of widely occurring natural products with various biological functions. We previously identified 4-hydroxy auxarconjugatin B (4-HAB) as anti‐inflammatory agent with an IC50 of ~20 µM. In this study, we synthesized a new anti‐inflammatory 4-HAB analogue, F240B, which has an IC50 of less than 1 µM. F240B dose-dependently induced autophagy by increasing autophagic flux, LC3 speck formation and acidic vesicular organelle formation. F240B inhibited NACHT, LRR and PYD domain-containing protein 3 (NLRP3) inflammasome activation through autophagy induction. In a mechanistic study, F240B inhibited interleukin (IL)-1β (IL-1β) precursor expression, promoted degradation of NLRP3 and IL-1β, and reduced mitochondrial membrane integrity loss in an autophagy-dependent manner. Additionally, F240B inhibited apoptosis-associated speck-like protein containing a CARD (ASC) oligomerization and speck formation without affecting the interaction between NLRP3 and ASC or NIMA-related kinase 7 (NEK7) and double-stranded RNA-dependent kinase (PKR). Furthermore, F240B exerted in vivo anti-inflammatory activity by reducing the intraperitoneal influx of neutrophils and the levels of IL-1β, active caspase-1, IL-6 and monocyte chemoattractant protein-1 (MCP-1) in lavage fluids in a mouse model of uric acid crystal-induced peritonitis. In conclusion, F240B attenuated the NLRP3 inflammasome through autophagy induction and can be developed as an anti-inflammatory agent in the future.

Increasing Autophagy ameliorate all-trans-retinal-activated NLRP3 Inflammasome 2 in human THP-1 macrophage cells

2021 ◽  
Author(s):  
Qingqing Xia ◽  
Lvxing Huang ◽  
Hengyi Chen ◽  
Yingying Zhou ◽  
Lingmin Zhang ◽  
...  
Keyword(s):  
Nlrp3 Inflammasome ◽  
Underlying Mechanism ◽  
Innate Immune ◽  
Cell Counting ◽  
Autophagic Flux ◽  
Inflammasome Activation ◽  
Nlrp3 Inflammasome Activation ◽  
Related Proteins ◽  
Excessive Activation ◽  
Insight Into

Abstract BackgroundProfound inflammation that mediated by innate immune sensors can be observed in retina, and is considered to play an important role in the pathogenesis of all-trans-retinal (atRAL)-caused retinal degeneration. However, the underlying mechanism remains elusive. MethodsCell viability was detected with Cell Counting Kit-8 (CCK-8). The concentration of IL-1β was evaluated using IL-1β ELISA Kits. The levels of autophagy-related proteins were measured by Western blotting. The measurement of autophagic flux was performed with virus vectors packing tandem monomeric mCherry-eGFP-tagged LC3B. ResultsWe focused on studying the effects of atRAL on macrophage cell line THP-1 and determining the underlying signal pathway through pharmacological and genetical manipulation. We first found the maturation and release of IL-1β was regulated by the activation of NLRP3 inflammasome. We secondly found that mitochondria-associated reactive oxygen species (ROS) were involved in the regulation of NLRP3 inflammasome activation and caspase 1 cleavage. Finally, we found that atRAL functionally activated autophagy in THP-1 cells, and atRAL-caused NLRP3 inflammasome activation is suppressed by autophagy. Overall, our results show atRAL simultaneously activates NLRP3 inflammasome and autophagy in THP-1 cells, and increasing autophagy leads to the inhibition of the excessive activation of NLRP3 inflammasome. Our study provides new insight into the pathogenesis of aging related retina degeneration.

α-Bisabolol protects against β-adrenergic agonist-induced myocardial infarction in rats by attenuating inflammation, lysosomal dysfunction, NLRP3 inflammasome activation and modulating autophagic flux

2020 ◽  
Vol 11 (1) ◽  
pp. 965-976 ◽  
Author(s):  
M. F. Nagoor Meeran ◽  
Sheikh Azimullah ◽  
Farah Laham ◽  
Saeed Tariq ◽  
Sameer N. Goyal ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Nlrp3 Inflammasome ◽  
Crucial Role ◽  
Autophagic Flux ◽  
Inflammasome Activation ◽  
Adrenergic Agonist ◽  
Lysosomal Dysfunction ◽  
Nlrp3 Inflammasome Activation

Emerging evidence demonstrates that NLRP3 inflammasome activation, lysosomal dysfunction, and impaired autophagic flux play a crucial role in the pathophysiology of myocardial infarction (MI).

scholarly journals Cystatin C Deficiency Increases LPS-Induced Sepsis and NLRP3 Inflammasome Activation in Mice

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 2071
Author(s):  
Monika Biasizzo ◽  
Mojca Trstenjak-Prebanda ◽  
Klemen Dolinar ◽  
Sergej Pirkmajer ◽  
Janja Završnik ◽  
...  
Keyword(s):  
Cystatin C ◽  
Nlrp3 Inflammasome ◽  
Mapk Signaling ◽  
Cysteine Protease Inhibitor ◽  
Ros Generation ◽  
Autophagic Flux ◽  
Inflammasome Activation ◽  
Nlrp3 Inflammasome Activation ◽  
Cathepsin Activity ◽  
Cysteine Cathepsin

Cystatin C is a potent cysteine protease inhibitor that plays an important role in various biological processes including cancer, cardiovascular diseases and neurodegenerative diseases. However, the role of CstC in inflammation is still unclear. In this study we demonstrated that cystatin C-deficient mice were significantly more sensitive to the lethal LPS-induced sepsis. We further showed increased caspase-11 gene expression and enhanced processing of pro-inflammatory cytokines IL-1β and IL-18 in CstC KO bone marrow-derived macrophages (BMDM) upon LPS and ATP stimulation. Pre-treatment of BMDMs with the cysteine cathepsin inhibitor E-64d did not reverse the effect of CstC deficiency on IL-1β processing and secretion, suggesting that the increased cysteine cathepsin activity determined in CstC KO BMDMs is not essential for NLRP3 inflammasome activation. The CstC deficiency had no effect on (mitochondrial) reactive oxygen species (ROS) generation, the MAPK signaling pathway or the secretion of anti-inflammatory cytokine IL-10. However, CstC-deficient BMDMs showed dysfunctional autophagy, as autophagy induction via mTOR and AMPK signaling pathways was suppressed and accumulation of SQSTM1/p62 indicated a reduced autophagic flux. Collectively, our study demonstrates that the excessive inflammatory response to the LPS-induced sepsis in CstC KO mice is dependent on increased caspase-11 expression and impaired autophagy, but is not associated with increased cysteine cathepsin activity.

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