scholarly journals Betulinic Acid Attenuates Oxidative Stress in the Thymus Induced by Acute Exposure to T-2 Toxin via Regulation of the MAPK/Nrf2 Signaling Pathway

Toxins ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 540 ◽  
Author(s):  
Lijuan Zhu ◽  
Xianglian Yi ◽  
Chaoyang Ma ◽  
Chenxi Luo ◽  
Li Kong ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Signaling Pathway ◽  
Betulinic Acid ◽  
Biological Activities ◽  
Mapk Signaling ◽  
Acute Exposure ◽  
Protective Effects ◽  
Pentacyclic Triterpenoid ◽  
Nrf2 Signaling Pathway ◽  
Mda Content

T-2 toxin, the most toxic of the trichothecenes, is widely found in grains and feeds, and its intake poses serious risks to the health of humans and animals. An important cytotoxicity mechanism of T-2 toxin is the production of excess free radicals, which in turn leads to oxidative stress. Betulinic acid (BA) has many biological activities, including antioxidant activity, which is a plant-derived pentacyclic triterpenoid. The protective effects and mechanisms of BA in blocking oxidative stress caused by acute exposure to T-2 toxin in the thymus of mice was studied. BA pretreatment reduced ROS production, decreased the MDA content, and increased the content of IgG in serum and the levels of SOD and GSH in the thymus. BA pretreatment also reduced the degree of congestion observed in histopathological tissue sections of the thymus induced by T-2 toxin. Besides, BA downregulated the phosphorylation of the p38, JNK, and ERK proteins, while it upregulated the expression of the Nrf2 and HO-1 proteins in thymus tissues. The results indicated that BA could protect the thymus against the oxidative damage challenged by T-2 toxin by activating Nrf2 and suppressing the MAPK signaling pathway.

scholarly journals Lipopolysaccharide exposure induces oxidative damage in Caenorhabditis elegans: protective effects of carnosine

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Jing Ma ◽  
Xiaoyuan Xu ◽  
Ranran Wang ◽  
Haijing Yan ◽  
Huijuan Yao ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Caenorhabditis Elegans ◽  
Signaling Pathway ◽  
P38 Mapk ◽  
Mapk Signaling ◽  
Protective Effects ◽  
Related Gene ◽  
Rt Pcr ◽  
C Elegans ◽  
Apoptosis Related Gene

Abstract Background The present study was designed to investigate the protective effects and mechanisms of carnosine on lipopolysaccharide (LPS)-induced injury in Caenorhabditis elegans. Methods C. elegans individuals were stimulated for 24 h with LPS (100 μg/mL), with or without carnosine (0.1, 1, 10 mM). The survival rates and behaviors were determined. The activities of superoxide dismutase (SOD), glutathione reductase (GR), and catalase (CAT) and levels of malondialdehyde (MDA) and glutathione (GSH) were determined using the respective kits. Reverse transcription polymerase chain reaction (RT-PCR) was performed to validate the differential expression of sod-1, sod-2, sod-3, daf-16, ced-3, ced-9, sek-1, and pmk-1. Western blotting was used to determine the levels of SEK1, p38 mitogen-activated protein kinase (MAPK), cleaved caspase3, and Bcl-2. C. elegans sek-1 (km2) mutants and pmk-1 (km25) mutants were used to elucidate the role of the p38 MAPK signaling pathway. Results Carnosine improved the survival of LPS-treated C. elegans and rescued behavioral phenotypes. It also restrained oxidative stress by decreasing MDA levels and increasing SOD, GR, CAT, and GSH levels. RT-PCR results showed that carnosine treatment of wild-type C. elegans up-regulated the mRNA expression of the antioxidant-related genes sod-1, sod-2, sod-3, and daf-16. The expression of the anti-apoptosis-related gene ced-9 and apoptosis-related gene ced-3 was reversed by carnosine. In addition, carnosine treatment significantly decreased cleaved caspase3 levels and increased Bcl-2 levels in LPS-treated C. elegans. Apoptosis in the loss-of-function strains of the p38 MAPK signaling pathway was suppressed under LPS stress; however, the apoptotic effects of LPS were blocked in the sek-1 and pmk-1 mutants. The expression levels of sek-1 and pmk-1 mRNAs were up-regulated by LPS and reversed by carnosine. Finally, the expression of p-p38MAPK and SEK1 was significantly increased by LPS, which was reversed by carnosine. Conclusion Carnosine treatment protected against LPS injury by decreasing oxidative stress and inhibiting apoptosis through the p38 MAPK pathway.

scholarly journals Protective effects of alfalfa saponins on oxidative stress-induced apoptotic cells

2020 ◽  
Vol 11 (9) ◽  
pp. 8133-8140
Author(s):  
Yalei Cui ◽  
Boshuai Liu ◽  
Xiao Sun ◽  
Zidan Li ◽  
Yanyan Chen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Signaling Pathway ◽  
Antioxidant System ◽  
Cell Apoptosis ◽  
Mapk Signaling ◽  
Mapk Signaling Pathway ◽  
Apoptotic Cells ◽  
Protective Effects

Alfalfa saponins defend against oxidative stress by enhancing the antioxidant system and further inhibit cell apoptosis by activating the MAPK signaling pathway.

scholarly journals Luteolin Alleviates AflatoxinB1-Induced Apoptosis and Oxidative Stress in the Liver of Mice through Activation of Nrf2 Signaling Pathway

Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1268
Author(s):  
Shahid Ali Rajput ◽  
Aftab Shaukat ◽  
Kuntan Wu ◽  
Imran Rashid Rajput ◽  
Dost Muhammad Baloch ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Liver Injury ◽  
Signaling Pathway ◽  
Aflatoxin B1 ◽  
Physiological Saline ◽  
Protective Effects ◽  
Biochemical Alterations ◽  
Protein Levels ◽  
Nrf2 Signaling Pathway ◽  
Induced Apoptosis

Aflatoxin B1 (AFB1), a threatening mycotoxin, usually provokes oxidative stress and causes hepatotoxicity in animals and humans. Luteolin (LUTN), well-known as an active phytochemical agent, acts as a strong antioxidant. This research was designed to investigate whether LUTN exerts protective effects against AFB1-induced hepatotoxicity and explore the possible molecular mechanism in mice. A total of forty-eight mice were randomly allocated following four treatment groups (n = 12): Group 1, physiological saline (CON). Group 2, treated with 0.75 mg/kg BW aflatoxin B1 (AFB1). Group 3, treated with 50 mg/kg BW luteolin (LUTN), and Group 4, treated with 0.75 mg/kg BW aflatoxin B1 + 50 mg/kg BW luteolin (AFB1 + LUTN). Our findings revealed that LUTN treatment significantly alleviated growth retardation and rescued liver injury by relieving the pathological and serum biochemical alterations (ALT, AST, ALP, and GGT) under AFB1 exposure. LUTN ameliorated AFB1-induced oxidative stress by scavenging ROS and MDA accumulation and boosting the capacity of the antioxidant enzyme (CAT, T-SOD, GSH-Px and T-AOC). Moreover, LUTN treatment considerably attenuates the AFB1-induced apoptosis in mouse liver, as demonstrated by declined apoptotic cells percentage, decreased Bax, Cyt-c, caspase-3 and caspase-9 transcription and protein with increased Bcl-2 expression. Notably, administration of LUTN up-regulated the Nrf2 and its associated downstream molecules (HO-1, NQO1, GCLC, SOD1) at mRNA and protein levels under AFB1 exposure. Our results indicated that LUTN effectively alleviated AFB1-induced liver injury, and the underlying mechanisms were associated with the activation of the Nrf2 signaling pathway. Taken together, LUTN may serve as a potential mitigator against AFB1-induced liver injury and could be helpful for the development of novel treatment to combat liver diseases in humans and/or animals.

scholarly journals Curcumin Protects Human Trophoblast HTR8/SVneo Cells from H2O2-Induced Oxidative Stress by Activating Nrf2 Signaling Pathway

Antioxidants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 121 ◽  
Author(s):  
Lina Qi ◽  
Jingle Jiang ◽  
Jingfei Zhang ◽  
Lili Zhang ◽  
Tian Wang
Keyword(s):  
Oxidative Stress ◽  
Oxidative Damage ◽  
Signaling Pathway ◽  
Protective Effects ◽  
Human Trophoblast ◽  
Nrf2 Signaling Pathway ◽  
Antioxidant Proteins ◽  
Pre Treatment ◽  
Induced Apoptosis ◽  
Excessive Accumulation

Pregnancy complications are associated with oxidative stress induced by accumulation of trophoblastic ROS in the placenta. We employed the human trophoblast HTR8/SVneo cell line to determine the effect of curcumin pre-treatment on H2O2-induced oxidative damage in HTR8/Sveo cells. Cells were pretreated with 2.5 or 5 μM curcumin for 24 h, and then incubated with 400 μM H2O2 for another 24 h. The results showed that H2O2 decreased the cell viability and induced excessive accumulation of reactive oxygen species (ROS) in HTR8/Sveo cells. Curcumin pre-treatment effectively protected HTR8/SVneo cells against oxidative stress-induced apoptosis via increasing Bcl-2/Bax ratio and decreasing the protein expression level of cleaved-caspase 3. Moreover, curcumin pre-treatment alleviated the excessive oxidative stress by enhancing the activity of antioxidative enzymes. The antioxidant effect of curcumin was achieved by activating Nrf2 and its downstream antioxidant proteins. In addition, knockdown of Nrf2 by Nrf2-siRNA transfection abolished the protective effects of curcumin on HTR8/SVneo cells against oxidative damage. Taken together, our results show that curcumin could protect HTR8/SVneo cells from H2O2-induced oxidative stress by activating Nrf2 signaling pathway.

scholarly journals Betulinic Acid Alleviates Spleen Oxidative Damage Induced by Acute Intraperitoneal Exposure to T-2 Toxin by Activating Nrf2 and Inhibiting MAPK Signaling Pathways

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 158
Author(s):  
Li Kong ◽  
Lijuan Zhu ◽  
Xianglian Yi ◽  
You Huang ◽  
Haoqiang Zhao ◽  
...  
Keyword(s):  
Oxidative Damage ◽  
Protein Expression ◽  
Signaling Pathway ◽  
Betulinic Acid ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Erythroid Cell ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Nrf2 Signaling Pathway

T-2 toxin, which is mainly produced by specific strains of Fusarium in nature, can induce immunotoxicity and oxidative stress, resulting in immune organ dysfunction and apoptosis. Betulinic acid (BA), a pentacyclic triterpenoids from nature plants, has been demonstrated to possess immunomodulating and antioxidative bioactivities. The purpose of the study was to explore the effect of BA on T-2 toxin-challenged spleen oxidative damage and further elucidate the underlying mechanism. We found that BA not only ameliorated the contents of serum total cholesterol (TC) and triglyceride (TG) but also restored the number of lymphocytes in T-2 toxin-induced mice. BA dose-dependently reduced the accumulation of reactive oxygen species (ROS), enhanced superoxide dismutase (SOD) activity, and decreased malondialdehyde (MDA) content, as well as increased the total antioxidant capacity (T-AOC) in the spleen of T-2-toxin-exposed mice. Moreover, BA reduced inflammatory cell infiltration in the spleen, improved the morphology of mitochondria and enriched the number of organelles in splenocytes, and dramatically attenuated T-2 toxin-triggered splenocyte apoptosis. Furthermore, administration of BA alleviated the protein phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinases (ERK); decreased the protein expression of kelch-like erythroid cell-derived protein with CNC homology [ECH]-associated protein1 (Keap1); and increased the protein expression of nuclear factor erythroid 2 [NF-E2]-related factor (Nrf2) and heme oxygenase-1 (HO-1) in the spleen. These findings demonstrate that BA defends against spleen oxidative damage associated with T-2 toxin injection by decreasing ROS accumulation and activating the Nrf2 signaling pathway, as well as inhibiting the mitogen-activated protein kinase (MAPK) signaling pathway.

Celastrol Protects RPE Cells from Oxidative Stress-Induced Cell Death via Activation of Nrf2 Signaling Pathway

2019 ◽  
Vol 19 (3) ◽  
pp. 172-182 ◽  
Author(s):  
Yeqi Zhou ◽  
Linbin Zhou ◽  
Kewen Zhou ◽  
Jingyue Zhang ◽  
Fu Shang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Signaling Pathway ◽  
Western Blotting ◽  
Retinal Pigment ◽  
Age Related Macular Degeneration ◽  
Protective Effects ◽  
Rpe Cells ◽  
Age Related ◽  
Nrf2 Signaling Pathway ◽  
Chemical Inhibition

Purpose: Oxidative stress to retinal pigment epithelial (RPE) cells and inflammation are closely related to the pathogenesis of age-related macular degeneration (AMD). Celastrol is a natural compound isolated from the root of Tripterygium wilfordii. Celastrol has been shown to have potent anti-inflammatory and anti-tumor effects in multiple disease models. The objective of this study was to test the anti-oxidative effects of celastrol in RPE cells and to investigate the underlying mechanisms. Methods: ARPE-19 cells were treated with hydrogen peroxide (H2O2) and menadione alone or in combination with celastrol. Cell viability and apoptosis were examined by CCK-8 and TUNEL assay, respectively. The expression of Nrf2 and its target genes, such as GCLM and HO-1 was determined by Western blotting. The knockdown of Nrf2 was done by transfecting ARPE-19 cells with lentivirus encoding shRNA against Nrf2. The knockdown efficiency was determined by real-time quantitative PCR and Western blotting. Results: Treatment of ARPE-19 cells with celastrol significantly attenuated the toxic effects of both H2O2 and menadione. Treatment with celastrol enhanced the expression of transcription factor Nrf2 and its targets, GCLM and HO-1. Knockdown of Nrf2 expression by shRNA partially abolished the protective effects of celastrol. Chemical inhibition of glutathione synthesis by L-buthionine-S,R-sulfoximine (BSO) completely abolished the protective effects of celastrol against H2O2 and menadione-induced damage. However, chemical inhibition of HO-1 activity by ZnPPIX did not reduce the protective effects of celastrol. Conclusion: This study provides evidence that treatment of RPE cells with celastrol shows potent protective effects against oxidative insults via activation of Nrf2 signaling pathway and upregulation of GCLM expression. This finding suggests that celastrol might be used as a potential therapeutic agent for oxidative stress-related eyes diseases, such as AMD.

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