scholarly journals Crosstalk between Peroxisomal Activities and Nrf2 Signaling in Porcine Embryos

Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 771
Author(s):  
Eui-Hyun Kim ◽  
Muhammad-Rosyid Ridlo ◽  
Byeong-Chun Lee ◽  
Geon A. Kim

Melatonin and phytanic acid (PA) are known to be involved in lipid metabolism and β-oxidation, in which peroxisomal activities also significantly participate. In addition, other studies have reported that the nuclear factor-erythroid-derived 2-like 2 (Nrf2 or NFE2L2) signaling pathway mediates lipid metabolism and its subsequent cascades. As these mechanisms are partially involved in porcine oocytes or embryonic development, we hypothesized that the factors governing these mechanisms could be interconnected. Therefore, we aimed to investigate possible crosstalk between peroxisomal activities and Nrf2 signaling in porcine embryos following melatonin and PA treatment. Porcine embryos were cultured for seven days after parthenogenetic activation, and subsequently treated with melatonin and PA, or injected with Pex19-targeted siRNAs. Real-time PCR, immunocytochemistry, and BODIPY staining were used to evaluate peroxisomal activities, Nrf2 signaling, and subsequent lipid metabolism. We found that melatonin/PA treatment enhanced embryonic development, whereas injection with Pex19-targeted siRNAs had the opposite effect. Moreover, melatonin/PA treatment upregulated peroxisomal activities, Nrf2 signaling, lipid metabolism, and mitochondrial membrane potentials, whereas most of these mechanisms were downregulated by Pex19-targeted siRNAs. Therefore, we suggest that there is a connection between the action of melatonin and PA and the Nrf2 signaling pathway and peroxisomal activities, which positively influences porcine embryonic development.

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yuanyuan Liu ◽  
Boxi Zhang ◽  
Jiahe Liu ◽  
Chunyu Qiao ◽  
Nianyu Xue ◽  
...  

As innate immune effector cells in the central nervous system (CNS), microglia not only are essential for the normal development of nervous system but also act on different neurological diseases, including Alzheimer’s disease (AD), Huntington's disease (HD), and other neuroinflammatory diseases. Mogroside V (Mog), a natural plant active ingredient and isolated form of Momordica grosvenori, has been shown to possess anti-inflammatory action, but few studies were carried out to investigate the effects of Mog on neuroinflammation. This study aimed to investigate the role of Mog in lipopolysaccharide- (LPS-) induced neuroinflammation and neuronal damage, revealing the underlying mechanisms. Our data indicated that Mog significantly inhibited the LPS-induced production of proinflammatory factors, such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-18, IL-6, cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and high mobility group box 1 (HMGB1) in BV-2 cells. We found that Mog also suppressed toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), the phosphorylation of mitogen-activated protein kinases (MAPKs), adenosine 5′-monophosphate- (AMP-) activated protein kinase (AMPK), nuclear factor kappa-B (NF-κB), and protein kinase B (AKT). Moreover, Mog also enhanced the expression of γ-glutamyl cysteine synthetase catalytic subunit (GCLC), modifier subunit (GCLM), heme oxygenase-1 (HO-1), and quinine oxidoreductase 1 (NQO1) proteins, mostly depending on the nuclear translation of nuclear factor erythroid-2 related factor 2 (Nrf2). In contrast, pretreatment with inhibitors of AKT can suppress the phosphorylation of AMPK, Nrf2, and its downstream proteins expression. In summary, Mog might play a protective role against LPS-induced neurotoxicity by inhibiting the TLR4-MyD88 and activation of AMPK/AKT-Nrf2 signaling pathway.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1417
Author(s):  
Pelin Telkoparan-Akillilar ◽  
Emiliano Panieri ◽  
Dilek Cevik ◽  
Sibel Suzen ◽  
Luciano Saso

Cancer is one of the most fatal diseases with an increasing incidence and mortality all over the world. Thus, there is an urgent need for novel therapies targeting major cancer-related pathways. Nuclear factor-erythroid 2-related factor 2 (NRF2) and its major negative modulator Kelch-like ECH-associated protein 1 (KEAP1) are main players of the cellular defense mechanisms against internal and external cell stressors. However, NRF2/KEAP1 signaling pathway is dysregulated in various cancers, thus promoting tumor cell survival and metastasis. In the present review, we discuss the mechanisms of normal and deregulated NRF2 signaling pathway focusing on its cancer-related functions. We further explore activators and inhibitors of this pathway as cancer targeting drug candidates in order to provide an extensive background on the subject.


2021 ◽  
Vol 33 (3) ◽  
pp. 25-32
Author(s):  
Jun Cai ◽  
Suyan Yao ◽  
Hao Wang ◽  
Wei Rong

Kaempferol (KF) is an important natural anti-inflammatory flavonol. Acute pancreatitis (AP) is an inflammatory disorder, which in about 20% cases may develop into severe acute pancreatitis (SAP) with a high mortality rate. This research was to study the effects and mechanism of kaempferol on SAP. SAP was induced by sodium taurocholate. The level of cytokines was analyzed by enzyme-linked-immunosorbent serologic assay. The expression of nuclear factor kappa B (NF-κB) and Kelch-like ECH-associated protein 1–nuclear factor erythroid 2-related factor 2 (Keap1–Nrf2) proteins was analyzed by Western blot assay. Pathological changes in the pancreas were evaluated by hematoxylin and eosin staining. Kaempferol attenuated pancreatic injury in SAP rats, including reduction in inflammatory infiltration and necrosis. The level of serum amylase and lipase was also decreased in kaempferol-treated SAP rats. Kaempferol inhibited the expression of inflammatory mediators (nuclear factor-α, Interlukin-1β, and Interlukin-6), and alleviated the oxidative stress characterized by the decreased malondialdehyde (MDA) and increased superoxide dismutase (SOD) levels. Kaempferol decreased the expression of cleaved caspase 3 and anti-apoptotic protein Bcl-2, which indicated that kaempferol could inhibit apoptosis of pancreatic cells in SAP rats. Kaempferol treatment could decrease the expression of p-p65 and the amount of nuclear Nrf2 (Nu-Nrf2), which demonstrated that kaempferol inhibited the NF-κB activation and enhanced the Keap1–Nrf2 pathway. Our research indicated that kaempferol could attenuate the pancreatic injury of SAP by regulating NF-κB and Keap1–Nrf2 signaling pathway. Kaempferol could serve as a natural candidate for treating SAP.


2021 ◽  
Author(s):  
Yu Ma ◽  
Siwen Li ◽  
Sixuan Tang ◽  
Shuzi Ye ◽  
Ningjuan Liang ◽  
...  

Abstract Hexavalent chromium [Cr(VI)] is a serious environmental pollutant and threatens human health. Although it has been confirmed that oxidative stress is the main mechanism of liver injury caused by Cr(VI) exposure, the related toxic target and effective intervention measures have not been found. Clusterin (CLU) is an acute phase response protein with cytoprotective and apoptosis delaying effects, and its expression has been confirmed to increase significantly after exposure to Cr(VI). In this study, we demonstrate that CLU acts on the Protein Kinase B (PKB/Akt)-Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2) signaling pathway to release Nrf2 into the nucleus. This to initiates the expression of a downstream protein, heme oxygenase 1 (HO-1), thereby attenuating the ubiquitination ability of Keap1 with Nrf2. We also demonstrated that CLU can affect oxidative stress through the Akt/Nrf2 pathway, which reduces the production of reactive oxygen species (ROS) induced by Cr(VI) and protects against Cr(VI)-induced oxidative stress-associated hepatotoxicity. This study demonstrates a the mechanism of Cr(VI)-induced hepatotoxicity, and indicates that CLU as an intervention target of oxidative stress can provide valuable experimental basis for the prevention and treatment of occupational diseases in Cr(VI)-exposed population.


Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 828
Author(s):  
Gerasimos P. Sykiotis

Nuclear factor, erythroid 2-like transcription factor 2 (Nrf2) and its cytoplasmic inhibitor, kelch-like ECH-associated protein 1 (Keap1), comprise a redox-responsive endogenous antioxidant defense module that orchestrates the expression of cytoprotective genes to maintain homeostasis [...]


2019 ◽  
Vol 18 (2) ◽  
pp. 176-182
Author(s):  
Chen Weiyan ◽  
Deng Wujian ◽  
Chen Songwei

Acute lung injury is a clinical syndrome consisting of a wide range of acute hypoxemic respiratory failure disorders. Sepsis is a serious complication caused by an excessive immune response to pathogen-induced infections, which has become a major predisposing factor for acute lung injury. Taxifolin is a natural flavonoid that shows diverse therapeutic benefits in inflammation- and oxidative stress-related diseases. In this study, we investigated the role of taxifolin in a mouse model of cecal ligation and puncture-induced sepsis. Cecal ligation and puncture-operated mice presented damaged alveolar structures, thickened alveolar walls, edematous septa, and hemorrhage compared to sham-treated controls. Cecal ligation and puncture mice also showed increased wet-to-dry (W/D) lung weight ratio and elevated total protein concentration and lactate dehydrogenase level in bronchoalveolar lavage fluid. Taxifolin treatment protected animals against sepsis-induced pulmonary damage and edema. Septic mice presented compromised antioxidant capacity, whereas the administration of taxifolin prior to cecal ligation and puncture surgery decreased malondialdehyde concentration and enhanced the levels of reduced glutathione and superoxide dismutase in mice with sepsis-induced acute lung injury. Moreover, cecal ligation and puncture-operated mice showed markedly higher levels of proinflammatory cytokines relative to sham-operated group, while taxifolin treatment effectively mitigated sepsis-induced inflammation in mouse lungs. Further investigation revealed that taxifolin suppressed the activation of the nuclear factor kappa-light-chain-enhancer of activated B cells signaling pathway in cecal ligation and puncture-challenged mice by regulating the phosphorylation of p65 and IκBα. In conclusion, our study showed that taxifolin alleviated sepsis-induced acute lung injury via the inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells signaling pathway, suggesting the therapeutic potential of taxifolin in the treatment sepsis-induced acute lung injury.


Author(s):  
Yuan Gu ◽  
Xiaochen Liu ◽  
Lele Liao ◽  
Yongquan Gao ◽  
Yu Shi ◽  
...  

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