Tanshinone IIA Suppresses Hypoxia-induced Apoptosis in Medial Vestibular Nucleus Cells Via a Skp2/BKCa Axis

2020 ◽  
Vol 26 (33) ◽  
pp. 4185-4194
Author(s):  
Jing-Jing Zhu ◽  
Shu-Hui Wu ◽  
Xiang Chen ◽  
Ting-Ting Jiang ◽  
Xin-Qian Li ◽  
...  

Background: The aim of the present study was to investigate the protective effects of Tanshinone IIA (Tan IIA) on hypoxia-induced injury in the medial vestibular nucleus (MVN) cells. Methods: An in vitro hypoxia model was established using MVN cells exposed to hypoxia. The hypoxia-induced cell damage was confirmed by assessing cell viability, apoptosis and expression of apoptosis-associated proteins. Oxidative stress and related indicators were also measured following hypoxia modeling and Tan IIA treatment, and the genes potentially involved in the response were predicted using multiple GEO datasets. Results: The results of the present study showed that Tan IIA significantly increased cell viability, decreased cell apoptosis and decreased the ratio of Bax/Bcl-2 in hypoxia treated cells. In addition, hypoxia treatment increased oxidative stress in MVN cells, and treatment with Tan IIA reduced the oxidative stress. The expression of SPhase Kinase Associated Protein 2 (SKP2) was upregulated in hypoxia treated cells, and Tan IIA treatment reduced the expression of SKP2. Mechanistically, SKP2 interacted with large-conductance Ca2+-activated K+ channels (BKCa), regulating its expression, and BKCa knockdown alleviated the protective effects of Tan IIA on hypoxia induced cell apoptosis. Conclusion: The results of the present study suggested that Tan IIA had a protective effect on hypoxia-induced cell damage through its anti-apoptotic and anti-oxidative activity via an SKP2/BKCa axis. These findings suggest that Tan IIA may be a potential therapeutic for the treatment of hypoxia-induced vertigo.

2021 ◽  
pp. 096032712110237
Author(s):  
Y-J Li ◽  
D-Z Zhang ◽  
Y Xi ◽  
C-A Wu

Objective: To explore the mechanism of dexmedetomidine (DEX)-mediated miR-134 inhibition in hypoxia-induced damage in PC12 cells. Methods: Hydrogen peroxide (H2O2)-stimulated PC12 cells were divided into control, H2O2, DEX + H2O2, miR-NC/inhibitor + H2O2, and miR-NC/ mimic + DEX + H2O2 groups. Cell viability and apoptosis were assessed by the 3-(4,5-dimethylthiazol(-2-y1)-2,5-diphenytetrazolium bromide (MTT) assay and Annexin V-FITC/PI staining, while gene and protein expression levels were detected by qRT-PCR and western blotting. Reactive oxygen species (ROS) levels were tested by 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA) staining, and malondialdehyde (MDA) content was determined with a detection kit. Results: DEX treatment decreased H2O2-elevated miR-134 expression. H2O2-induced PC12 cell damage was improved by DEX and miR-134 inhibitor; additionally, cell viability was increased, while cell apoptosis was reduced. In addition, both DEX and miR-134 inhibitor reduced the upregulated expression of cleaved caspase-3 and increased the downregulated expression of Bcl-2 in H2O2-induced PC12 cells. However, compared to that in the DEX + H2O2 group, cell viability in the mimic + DEX + H2O2 group was decreased, and the apoptotic rate was elevated with increased cleaved caspase-3 and decreased Bcl-2 expression. Inflammation and oxidative stress were increased in H2O2-induced PC12 cells but improved with DEX or miR-134 inhibitor treatment. However, this improvement of H2O2-induced inflammation and oxidative stress induced by DEX in PC12 cells could be reversed by the miR-134 mimic. Conclusion: DEX exerts protective effects to promote viability and reduce cell apoptosis, inflammation, and oxidative stress in H2O2-induced PC12 cells by inhibiting the expression of miR-134.


2019 ◽  
Vol 8 (5) ◽  
pp. 641-653 ◽  
Author(s):  
Jinbao Gao ◽  
Yunjun Li ◽  
Wende Li ◽  
Haijiang Wang

Abstract Neuronal death caused by inflammatory cytokine-mediated neuroinflammation is being extensively explored. Thioredoxin reductase (TrxR) 2 is a novel mediator of inflammation response. In the current study, we focus on the mechanisms of TrxR2 overexpression in inflammation-mediated neuronal death. LPS was used to induce neuroinflammation in N2a cells in vitro. Adenovirus-loaded TrxR2 was transfected into N2a cells to up-regulate TrxR2 expression. Then, cell viability was determined via MTT assay and TUNEL assay. Apoptosis was measured via western blotting and ELISA. Oxidative stress was detected via ELISA and flow cytometry. A pathway inhibitor was used to verify the role of the Akt–Parkin pathway in the LPS-mediated N2a cell death in the presence of TrxR2 overexpression. With the help of immunofluorescence assay and western blotting, we found that TrxR2 expression was significantly reduced in response to LPS treatment, and this effect was associated with N2a cell death via apoptosis. At the molecular level, TrxR2 overexpression elevated the activity of the Akt–Parkin pathway, as evidenced by the increased expression of p-Akt and Parkin. Interestingly, inhibition of the Akt–Parkin pathway abolished the regulatory effect of TrxR2 on LPS-treated N2a cells, as evidenced by the decreased cell viability and increased apoptotic ratio. Besides, TrxR2 overexpression also reduced oxidative stress, inflammation factor transcription and mitochondrial apoptosis. However, inhibition of Akt–Parkin axis abrogated the protective effects of TrxR2 on redox balance, mitochondrial performance and cell survival. LPS-mediated neuronal death was linked to a drop in TrxR2 overexpression and the inactivation of the Akt–Parkin pathway. Overexpression of TrxR2 sustained mitochondrial function, inhibited oxidative stress, repressed inflammation response, and blocked mitochondrial apoptosis, finally sending a pro-survival signal for the N2a cells in the setting of LPS-mediated inflammation environment.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Qingqiang Xu ◽  
Wenwen Shi ◽  
Pan Lv ◽  
Wenqi Meng ◽  
Guanchao Mao ◽  
...  

AbstractAflatoxin B1 (AFB1) is a potent hepatocarcinogen in humans and exposure to AFB1 is known to cause both acute and chronic hepatocellular injury. As the liver is known to be the main target organ of aflatoxin, it is important to identify the key molecules that participate in AFB1-induced hepatotoxicity and to investigate their underlying mechanisms. In this study, the critical role of caveolin-1 in AFB1-induced hepatic cell apoptosis was examined. We found a decrease in cell viability and an increase in oxidation and apoptosis in human hepatocyte L02 cells after AFB1 exposure. In addition, the intracellular expression of caveolin-1 was increased in response to AFB1 treatment. Downregulation of caveolin-1 significantly alleviated AFB1-induced apoptosis and decreased cell viability, whereas overexpression of caveolin-1 reversed these effects. Further functional analysis showed that caveolin-1 participates in AFB1-induced oxidative stress through its interaction with Nrf2, leading to the downregulation of cellular antioxidant enzymes and the promotion of oxidative stress-induced apoptosis. In addition, caveolin-1 was found to regulate AFB1-induced autophagy. This finding was supported by the effect that caveolin-1 deficiency promoted autophagy after AFB1 treatment, leading to the inhibition of apoptosis, whereas overexpression of caveolin-1 inhibited autophagy and accelerated apoptosis. Interestingly, further investigation showed that caveolin-1 participates in AFB1-induced autophagy by regulating the EGFR/PI3K-AKT/mTOR signaling pathway. Taken together, our data reveal that caveolin-1 plays a crucial role in AFB1-induced hepatic cell apoptosis via the regulation of oxidation and autophagy, which provides a potential target for the development of novel treatments to combat AFB1 hepatotoxicity.


2020 ◽  
Vol 11 ◽  
Author(s):  
Xiaoye Fan ◽  
Wei Wei ◽  
Jingbo Huang ◽  
Liping Peng ◽  
Xinxin Ci

Cisplatin (CDDP) is a widely used drug for cancer treatment that exhibits major side effects in normal tissues, such as nephrotoxicity in kidneys. The Nrf2 signaling pathway, a regulator of mitochondrial dysfunction, oxidative stress and inflammation, is a potential therapeutic target in CDDP-induced nephrotoxicity. We explored the underlying mechanisms in wild-type (WT) and Nrf2−/− mice on CDDP-induced renal dysfunction in vivo. We found that Nrf2 deficiency aggravated CDDP-induced nephrotoxicity, and Daph treatment significantly ameliorated the renal injury characterized by biochemical markers in WT mice and reduced the CDDP-induced cell damage. In terms of the mechanism, Daph upregulated the SIRT1 and SIRT6 expression in vivo and in vitro. Furthermore, Daph inhibited the expression level of NOX4, whereas it activated Nrf2 translocation and antioxidant enzymes HO-1 and NQO1, and alleviated oxidative stress and mitochondrial dysfunction. Moreover, Daph suppressed CDDP-induced NF-κB and MAPK inflammation pathways, as well as p53 and cleaved caspase-3 apoptosis pathways. Notably, the protective effects of Daph in WT mice were completely abrogated in Nrf2−/− mice. Moreover, Daph enhanced, rather than attenuated, the tumoricidal effect of CDDP.


2021 ◽  
Author(s):  
Mei Tang ◽  
Lin Jiang ◽  
Gaerma Dugujia ◽  
Yuche Wu ◽  
Xiao Liu ◽  
...  

Abstract Background: Tianxiangdan capsule (TXD), developed in our hospital, has been clinically used in the treatment of coronary heart disease angina pectoris. This study aimed at evaluating the mechanisms of TXD against myocardial ischemia and to provide evidence for its subsequent clinical application. METHODS: Active components and mechanisms of action of TXD against myocardial ischemia were predicted and analyzed by network pharmacology and molecular docking. The oxidative damage model was established using H2O2, which caused myocardial cell damage. The MTT assay was used to evaluate cell viability, Hoechst33342 staining, while cleaved caspase-3 immunofluorescence staining was used to determine cell apoptosis. Fluorescent probe method detected ROS and intracellular Ca2+, while spectrophotometry was used to measure SOD, MDA, and NO levels in myocardial cells. Western blotting was used to detect the expression levels of ESR1, PI3K, AKT, and eNOS in cells. RESULTS: It was found that TXD plays a protective role in myocardial ischemia through the estrogen pathway, and its main active components were isoflavones. The TXD drug-containing plasma exhibited increased cell survival rates and suppressed MDA levels, elevated SOD and NO levels, and significantly suppressed ROS levels as well as intracellular Ca2+ levels. Moreover, the TXD drug-containing plasma pretreated cells had significantly suppressed PI3K and AKT expression levels, as well as elevated ESR1 and eNOS expression levels. Conclusion: TXD may exhibit estrogen-like effects, through the estrogen pathway enhances cardiomyocytes' antioxidant capacities, and improves oxidative stress injury as well as cell apoptosis.


2020 ◽  
Vol 19 (6) ◽  
pp. 1197-1201 ◽  
Author(s):  
Jing Li ◽  
Yue Liu ◽  
Li Wang ◽  
Zhaowei Gu ◽  
Zhigang Huan ◽  
...  

Purpose: To investigation the protective effects of hesperetin against 6-hydroxydopamine (6-OHDA)- induced neurotoxicity. Methods: SH-SY5Y cells were incubated with 6-OHDA to create an in vitro model of neurotoxicity. This model was used to test the neuroprotective effects of hesperetin. Cell viability was assessed by MTT and lactate dehydrogenase (LDH) release assays. Flow cytometry and western blot were used to quantify apoptosis. Oxidative stress was evaluated by determining intracellular glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and reactive oxygen species (ROS). Results: In SH-SY5Y cells, treatment with 6-OHDA decreased cell viability and promoted LDH release. However, exogenous hesperetin protected against 6-OHDA-mediated toxicity. Similarly, although incubation with 6-OHDA induced apoptosis and increased cleaved caspase-3 and -9 levels, treatment with hesperetin protected against these effects. Treatment with 6-OHDA also led to significant oxidative stress, as indicated by reduced GSH and SOD levels and increased MDA and ROS levels in SH-SY5Y cells. However, these changes were reversed by pre-treatment with hesperetin. Of interest, hesperetin led to changes in 6-OHDA-induced expression of NRF2, heme oxygenase-1 (HO-1), glutamate-cysteine ligase (GCL) catalytic subunit (GCLC), and GCL modulatory (GCLM). Conclusion: Hesperetin protects against cell toxicity, apoptosis, and oxidative stress via activation of NRF2 pathway in a 6-OHDA-induced model of neurotoxicity. Future studies should investigate the use of hesperetin as a potential therapeutic approach for prevention or management of Parkinson’s disease. Keywords: Hesperetin, 6-OHDA, Neurotoxicity, NRF2, Parkinson’s disease


2021 ◽  
Author(s):  
Huanbin Liu ◽  
Yidi Zhang ◽  
Jinjun Jiang ◽  
Yulong Luo ◽  
Jingxin Zhao ◽  
...  

Abstract Background: Recent studies have demonstrated that airway basal stem cells (BCs) transplantation can ameliorate bleomycin-induced idiopathic pulmonary fibrosis (IPF) through lung regeneration promotion. However, BCs under oxidative stress in the alveolar microenvironment are poor in survival, causing unsatisfied efficacy of BCs transplantation. In this study, we investigated whether Coenzyme Q10(CoQ10) counteracts oxidative stress in the alveolar microenvironment, thus improved the efficacy of BCs transplantation for IPF treatment.Methods: The protective effects of CoQ10 on H2O2-induced BCs apoptosis and cytoplasmic reactive oxygen species (ROS) level were tested by flow cytometry in vitro. The therapeutic effects of BCs combined with CoQ10 were compared to a single BCs transplantation protocol in IPF treatment after two weeks and were evaluated by parameters including changes of body weight and survival rate, as well as various levels of pulmonary inflammation, α-SMA expression and hydroxyproline (HYP) in IPF mice lung tissues.Results: CoQ 10 preincubation with BCs (10 mM, 24 h) significantly reduced the late apoptosis of BCs and the number of oxidative stressful BCs as a result of H2O2 stimulation (1mM, 6h) in vitro. IPF mice models were constructed through bleomycin (5 mg/Kg) intratracheal instillation. Bleomycin-induced IPF mice showed weight loss continuously and mortality increased progressively during modeling. Serious pulmonary inflammatory cell infiltration, collagen fiber proliferation, and collagen protein deposition were observed in lung tissues of IPF mice. Though BCs transplantation alone improved indicators above in bleomycin-induced IPF mice to some extent, the combination with CoQ10 improved the transplantation efficacy and obtained better therapeutic effects.Conclusion:CoQ10 blocked H2O2-induced apoptosis of BCs and ROS production in vitro, and enhanced the efficacy of BCs transplantation on bleomycin-induced IPF in mice.


2004 ◽  
Vol 92 (6) ◽  
pp. 887-894 ◽  
Author(s):  
R.-F. S. Huang ◽  
H.-C. Yaong ◽  
S.-C. Chen ◽  
Y.-F. Lu

Folate has recently been proposed as a new antioxidant. Folate supplementation may have a protective effect in counteracting oxidant-induced apoptotic damage. The present studies were undertaken to examine whether there is a direct link between folate levels, antioxidant capability and reduced apoptotic damage. Using anin vitrocellular model of 7-ketocholesterol (KC)-induced apoptosis, U937 cells were pre-cultured with a folate-deficient medium supplemented with various levels of folate (2–1500μmol/l) before treatment with 7-KC. Apoptotic markers, mitochondria-associated death signals and levels of reactive oxygen species were assayed. After treatment with 7-KC for 30h, low and high levels of folate supplementation significantly (P<0.05) reduced nuclear DNA loss. Only high levels of folate supplementation (>1000μmol/l) were effective in counteracting 7-KC-promoted apoptotic membrane phosphatidylserine exposure and DNA laddering. The attenuation of 7-KC-induced apoptotic damage by high-dose folate supplementation coincided with a partial normalization of mitochondria membrane potential dissipation, a suppression of cytochromecrelease and an inhibition of procaspase 3 activation. The prevention of mitochondrial dysfunctions and apoptotic processes was associated with antioxidant actions of high-dose folate by a marked scavenging of intracellular superoxide. Collectively, our present results demonstrate thatin vitrofolate supplementation exerts differentially protective effects against 7-KC-induced damage. High-dose supplementation alleviates oxidative stress, mitochondria-associated death signalling and apoptosis induced by 7-KC. However, thein vivorelevance is not clear and requires further study.


2021 ◽  
Vol 14 (5) ◽  
pp. 444
Author(s):  
Ramona Meanti ◽  
Laura Rizzi ◽  
Elena Bresciani ◽  
Laura Molteni ◽  
Vittorio Locatelli ◽  
...  

Hexarelin, a synthetic hexapeptide, exerts cyto-protective effects at the mitochondrial level in cardiac and skeletal muscles, both in vitro and in vivo, may also have important neuroprotective bioactivities. This study examined the inhibitory effects of hexarelin on hydrogen peroxide (H2O2)-induced apoptosis in Neuro-2A cells. Neuro-2A cells were treated for 24 h with various concentrations of H2O2 or with the combination of H2O2 and hexarelin following which cell viability and nitrite (NO2−) release were measured. Cell morphology was also documented throughout and changes arising were quantified using Image J skeleton and fractal analysis procedures. Apoptotic responses were evaluated by Real-Time PCR (caspase-3, caspase-7, Bax, and Bcl-2 mRNA levels) and Western Blot (cleaved caspase-3, cleaved caspase-7, MAPK, and Akt). Our results indicate that hexarelin effectively antagonized H2O2-induced damage to Neuro-2A cells thereby (i) improving cell viability, (ii) reducing NO2− release and (iii) restoring normal morphologies. Hexarelin treatment also reduced mRNA levels of caspase-3 and its activation, and modulated mRNA levels of the BCL-2 family. Moreover, hexarelin inhibited MAPKs phosphorylation and increased p-Akt protein expression. In conclusion, our results demonstrate neuroprotective and anti-apoptotic effects of hexarelin, suggesting that new analogues could be developed for their neuroprotective effects.


2021 ◽  
Vol 8 (10) ◽  
pp. 220
Author(s):  
Flavia Girolami ◽  
Alessia Candellone ◽  
Watanya Jarriyawattanachaikul ◽  
Giorgia Meineri ◽  
Carlo Nebbia ◽  
...  

The treatment of choice for feline hyperthyroidism is the administration of the antithyroid drug methimazole. Both the endocrinopathy and the drug adverse reactions (e.g., hepatotoxicosis, gastrointestinal disorders, and renal injury) are partly due to oxidative stress and redox unbalance. This study investigated the free radical production and the impairment of the antioxidant barrier induced by methimazole in an in vitro model of feline renal epithelium. The protective effects of quercetin and resveratrol were also explored. CRFK cells were incubated with a methimazole concentration equivalent to the maximum plasma levels in orally treated cats (4 µM), in the presence or absence of either one of the two selected antioxidants at different time-points (up to 72 h). Cell viability, ROS production, GSH levels, and mRNA expression of antioxidant enzymes (i.e., CAT, SOD, GPx, and GST) were assessed. Methimazole impaired cell viability and increased ROS levels in a time-dependent manner. Similarly, GSH content and CAT, SOD, and GPx3 expression were higher compared with control cells. Such effects were significantly counteracted by quercetin. These results provide new insights about the mechanisms underlying the methimazole-related side effects frequently observed in hyperthyroid cats. They also support the use of quercetin in the management of feline hyperthyroidism.


Sign in / Sign up

Export Citation Format

Share Document