scholarly journals The Ferroptosis-NLRP1 Inflammasome: The Vicious Cycle of an Adverse Pregnancy

2021 ◽  
Vol 9 ◽  
Author(s):  
Li Meihe ◽  
Gao Shan ◽  
Kang Minchao ◽  
Wu Xiaoling ◽  
An Peng ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Model ◽  
Lipid Peroxides ◽  
Inflammasome Activation ◽  
Trophoblast Cells ◽  
Expression Levels ◽  
Nlrp1 Inflammasome ◽  
Transferrin Receptor 1 ◽  
Downward Spiral ◽  
Adverse Pregnancy

One of the hallmarks of placental dysfunction is the increase of oxidative stress. This process, along with the overexpression of the inflammasome, creates a downward spiral that can lead to a series of severe pregnancy complications. Ferroptosis is a form of iron-mediated cell death involving the accumulation of reactive oxygen species, lipid peroxides. In this study, the rats’ model of oxidative stress abortion was established, and hydrogen peroxide (H2O2) was used to establish a cellular model of placental oxidative stress. RNAi, western blot, and immunofluorescence were used to evaluate the expression of specific markers of ferroptosis and the expression of the inflammasome in placental trophoblast cells. We observed excessive levels of ferroptosis and inflammasome activation in both rats’ model and placental trophoblast cell model of oxidative stress. When the NLRP1 inflammasome was silenced, the expression levels of GSH and Glutathione peroxidase 4 (GPX4) were increased, while the expression levels of transferrin receptor 1 (TFR1), acyl-CoA synthetase long-chain family member 4 (ACSL4), Superoxide dismutase (SOD), and Malondialdehyde (MDA) were decreased. However, when an NLRP1 activator was applied, we observed the opposite phenomenon. We further explored the mechanisms underlying the actions of ferroptosis to inflammasomes. The expression levels of NLRP1, NLRP3, IL-1β, and caspase-1 were positively correlated with the ferroptosis following the application of ferroptosis inhibitor (ferrostatin-1) and ferroptosis activator (erastin). The existence of ferroptosis was demonstrated in the oxidative stress model of placental trophoblast cells; the results also indicate ferroptosis is linked with the expression of NLRP1 inflammasome. These findings may provide a valuable therapeutic target for the pathogenesis of pregnancy-related diseases.

scholarly journals Autophagy in the HTR-8/SVneo Cell Oxidative Stress Model Is Associated with the NLRP1 Inflammasome

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Meihe Li ◽  
Tao Sun ◽  
Xiaoling Wu ◽  
Peng An ◽  
Xili Wu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Positive Control ◽  
Pathological Process ◽  
Beclin 1 ◽  
Expression Level ◽  
Control Group ◽  
Inflammasome Activation ◽  
Trophoblast Cells ◽  
Nlrp1 Inflammasome ◽  
Stress Damage

We investigated whether there was activation of NLRP1 inflammasomes and excessive autophagy in oxidative stress damage. And we further demonstrate whether there is a cascade relationship between the activation of NLRP1 inflammasomes and the phenomenon of excessive autophagy. To observe the expression level of the NLRP1 inflammasome group in the pathological process of trophoblast cell oxidative stress, western blot, immunofluorescence, and qRT-PCR were performed. Autophagy in trophoblast cells after the action of H2O2 was detected by using normal trophoblast cells’ NLRP1-specific activator (MDP) as a positive control. The presence of excessive autophagy was determined by comparing it with the autophagy-related proteins in normal trophoblast cells. Through siRNA-NLRP1, we investigated the role of oxidative stress and the NLRP1 inflammasome in autophagy in cells. 100 μmol MDP for 24 hours can be used as the optimal concentration of the NLRP1 activator. In human placental trophoblast oxidative stress, the model group significantly increased the expression level of inflammasome IL-1β, CASP1, and NLRP1, compared with the control group NLRP3, and LC3-II, Beclin-1, ATG5, ATG7, and p62 overactivated the autophagy ability of cells. After the activation of NLRP1, the expression of these inflammasomes increased, accompanied by the decrease in autophagy. After the expression of NLRP1 was silenced by RNAi, the expression of inflammasome IL-1β, CASP1, and NLRP3 was also decreased. Still, the autophagy level was increased, which was manifested by the high expression of LC3-II, Beclin-1, ATG5, and ATG7 and the decrease in p62. Trophoblast cells showed the expression of NLRP1 protein and excessive autophagy under oxidative stress. Simultaneously, the NLRP1 inflammasome of trophoblast cells in the state of oxidative stress was correlated with autophagy. Inflammasome activation and autophagy were shown to be linked and to influence each other mutually. These may also provide new therapeutic targets in a pathological pregnancy.

scholarly journals Inhibition of Nrf2/HO-1 signaling leads to increased activation of the NLRP3 inflammasome in osteoarthritis

2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Zhuming Chen ◽  
Huan Zhong ◽  
Jinsong Wei ◽  
Sien Lin ◽  
Zhixian Zong ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Synovial Tissue ◽  
Subchondral Bone ◽  
Nlrp3 Inflammasome ◽  
Cell Model ◽  
Cruciate Ligament ◽  
Inflammasome Activation ◽  
Dependent Manner ◽  
Pathological Changes ◽  
Medial Meniscectomy

Abstract Introduction Osteoarthritis (OA) is an inflammatory disease of the joints that causes progressive disability in the elderly. Reactive oxygen species (ROS) play an important role in OA development; they may activate the NLRP3 inflammasome, thereby inducing the secretion of proinflammatory IL-1β and IL-18, leading to the aggravation of the downstream inflammatory response. Nrf2 is a key transcription factor that regulates the expression of antioxidant enzymes that protect against oxidative stress and tissue damage. We aimed to explore the underlying mechanism of OA development by investigating NLRP3, ASC, Nrf2, and HO-1 expression in synovia and their regulatory networks in OA. Methods Human total knee replacement samples were subjected to histology and micro-CT analysis to determine the pathological changes in the cartilage and subchondral bone and to assess the expression of inflammation-related markers in the synovial tissue by immunohistochemistry (IHC), qRT-PCR, and Western blot. To investigate these pathological changes in an OA animal model, adult Sprague-Dawley rats were subjected to anterior cruciate ligament transection and medial meniscectomy. Articular cartilage and subchondral bone changes and synovial tissue were also determined by the same methods used for the human samples. Finally, SW982 cells were stimulated with lipopolysaccharide (LPS) as an in vitro inflammatory cell model. The correlation between NLRP3 and Nrf2 expression was confirmed by knocking down NLRP3 or Nrf2. Results Cartilage destruction and subchondral bone sclerosis were found in the OA patients and OA model rats. Significantly increased expression levels of NLRP3, ASC, Nrf2, and HO-1 were found in the synovial tissue from OA patients. NLRP3, ASC, Nrf2, and HO-1 expression in the synovium was also upregulated in the OA group compared with the sham group. Furthermore, the NLRP3, Nrf2, HO-1, IL-1β, and IL-18 expression in LPS-treated SW982 cells was increased in a dose-dependent manner. As expected, the expression of NLRP3 was upregulated, and the expression of IL-1β and IL-18 was downregulated after Nrf2 silencing. However, knocking down NLRP3 did not affect the expression of Nrf2. Conclusions ROS-induced oxidative stress may be the main cause of NLRP3 inflammasome activation and subsequent release of downstream factors during OA development. Nrf2/HO-1 signaling could be a key pathway for the activation of the NLRP3 inflammasome, which may contribute to the progression of OA. Herein, we discovered a novel role of Nrf2/HO-1 signaling in the production of NLRP3, which may facilitate the prevention and treatment of OA.

scholarly journals Novel Insights into the Regulatory Role of Nuclear Factor (Erythroid-Derived 2)-Like 2 in Oxidative Stress and Inflammation of Human Fetal Membranes

2020 ◽  
Vol 21 (17) ◽  
pp. 6139 ◽  
Author(s):  
Ramkumar Menon ◽  
Morgan R Peltier
Keyword(s):  
Oxidative Stress ◽  
Heme Oxygenase ◽  
Water Soluble ◽  
Fetal Membrane ◽  
Fetal Membranes ◽  
Peroxisome Proliferator ◽  
Nuclear Factor ◽  
Western Blots ◽  
Adverse Pregnancy ◽  
Nrf2 Expression

Fetal membrane dysfunction in response to oxidative stress (OS) is associated with adverse pregnancy outcomes. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is one of the regulators of innate OS response. This study evaluated changes in Nrf2 expression and its downstream targets heme oxygenase (HO-1) and peroxisome proliferator-activated receptor gamma (PPARγ) in fetal membranes during OS and infection in vitro. Furthermore, we tested the roles of sulforaphane (SFN; an extract from cruciferous vegetables) and trigonelline (TRN; an aromatic compound in coffee) in regulating Nrf2 and its targets. Fetal membranes (n = 6) collected at term were placed in an organ explant system were treated with water-soluble cigarette smoke extract (CSE), an OS inducer (1:10), and lipopolysaccharide (LPS; 100 ng/mL). Nrf2 expression, expression, its enhancement by sulforaphane (SFN, 10 µM/mL) and down regulation by TRN (10uM/mL) was determined by western blots. Expression of Nrf2 response elements PPARγ (western) heme oxygenase (HO-1), and IL-6 were quantified by ELISA. CSE and LPS treatment of fetal membranes increased nrf2, but reduced HO-1 and PPARγ and increased IL-6. Co-treatment of SFN, but not with TRN, with CSE and LPS increased Nrf2 substantially, as well as increased HO-1 and PPARγ and reduced IL-6 expression. Risk factor-induced Nrf2 increase is insufficient to generate an antioxidant response in fetal membranes. Sulforaphane may enhance innate antioxidant and anti-inflammatory capacity by increasing NRF-2 expression.

scholarly journals Crosstalk between Long-Term Sublethal Oxidative Stress and Detrimental Inflammation as Potential Drivers for Age-Related Retinal Degeneration

Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 25
Author(s):  
Lara Macchioni ◽  
Davide Chiasserini ◽  
Letizia Mezzasoma ◽  
Magdalena Davidescu ◽  
Pier Luigi Orvietani ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Molecular Mechanisms ◽  
Age Related Macular Degeneration ◽  
Inflammasome Activation ◽  
Related Factor ◽  
Nuclear Factor ◽  
Rpe Cells ◽  
Age Related ◽  
Oxidative Insult

Age-related retinal degenerations, including age-related macular degeneration (AMD), are caused by the loss of retinal pigmented epithelial (RPE) cells and photoreceptors. The pathogenesis of AMD, deeply linked to the aging process, also involves oxidative stress and inflammatory responses. However, the molecular mechanisms contributing to the shift from healthy aging to AMD are still poorly understood. Since RPE cells in the retina are chronically exposed to a pro-oxidant microenvironment throughout life, we simulated in vivo conditions by growing ARPE-19 cells in the presence of 10 μM H2O2 for several passages. This long-term oxidative insult induced senescence in ARPE-19 cells without affecting cell proliferation. Global proteomic analysis revealed a dysregulated expression in proteins involved in antioxidant response, mitochondrial homeostasis, and extracellular matrix organization. The analyses of mitochondrial functionality showed increased mitochondrial biogenesis and ATP generation and improved response to oxidative stress. The latter, however, was linked to nuclear factor-κB (NF-κB) rather than nuclear factor erythroid 2–related factor 2 (Nrf2) activation. NF-κB hyperactivation also resulted in increased pro-inflammatory cytokines expression and inflammasome activation. Moreover, in response to additional pro-inflammatory insults, senescent ARPE-19 cells underwent an exaggerated inflammatory reaction. Our results indicate senescence as an important link between chronic oxidative insult and detrimental chronic inflammation, with possible future repercussions for therapeutic interventions.

scholarly journals Subsequent treatment of leafy vegetables with low doses of UVB-radiation does not provoke cytotoxicity, genotoxicity, or oxidative stress in a human liver cell model

2021 ◽  
pp. 101327
Author(s):  
Melanie Wiesner-Reinhold ◽  
João Victor Dutra Gomes ◽  
Corinna Herz ◽  
Hoai Thi Thu Tran ◽  
Susanne Baldermann ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Liver Cell ◽  
Human Liver ◽  
Cell Model ◽  
Subsequent Treatment ◽  
Leafy Vegetables ◽  
Low Doses ◽  
Uvb Radiation ◽  
Human Liver Cell ◽  
Liver Cell Model

HSP20 Exerts a Protective Effect on Preeclampsia by Regulating Function of Trophoblast Cells Via Akt Pathways

2018 ◽  
Vol 26 (7) ◽  
pp. 961-971 ◽  
Author(s):  
Fanfan Li ◽  
Yin Xie ◽  
Yuanyuan Wu ◽  
Mengzhou He ◽  
Meitao Yang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Signaling Pathway ◽  
Akt Signaling ◽  
Extravillous Trophoblast ◽  
Akt Signaling Pathway ◽  
Trophoblast Cells ◽  
Heat Shock Protein 20 ◽  
Apoptosis Index ◽  
Proliferation And Apoptosis ◽  
Associated Proteins

Preeclampsia (PE) remains the leading cause of maternal and fetal morbidity and mortality. Excessive apoptosis of the placenta and poor remodeling of spiral arteries caused by insufficient invasion of trophoblast cells into uterus have been implicated in the pathogenesis of PE. Accumulating evidence showed that heat shock protein 20 (HSP20) is closely associated with the proliferation, apoptosis, and metastasis of tumor cells. However, little is known about whether HSP20 plays a role in the development of PE. In this study, we detected the apoptosis index and the expressions of HSP20 and apoptosis-associated proteins in the placentas from PE and normal pregnancies. We found that HSP20 was reversely related to the apoptosis rate and the levels of proapoptotic proteins. Moreover, we identified that HSP20 could suppress the proliferation and apoptosis of trophoblast cells, turning them into a more invasive phenotype. Additionally, H2O2-induced oxidative stress was significantly alleviated, and several key proteins on the Akt signaling pathway were upregulated in HSP20-overexpressing trophoblast cells. These findings strongly suggested that HSP20 might play a role in the remodeling of spiral arteries through affecting the invasiveness of extravillous trophoblast cells via Akt signaling pathway, and the dysregulation of it might contribute to the pathophysiology of PE.

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