Apnea-Induced Hypoxemia Stimulates the Adaptive Response to Oxidative Stress in Elephant Seals (original) (raw)
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Doxorubicin (Dox) is a highly effective antineoplastic drug. However, Dox-induced apoptosis in cardiomyocytes leads to irreversible degenerative cardiomyopathy, which limits Dox clinical application. Schisandrin B (Sch B), a dibenzocyclooctadiene derivative isolated from the fruit of Schisandra chinensis, has been shown to protect against oxidative damage in liver, heart and brain tissues in rodents. In current study, we investigated possible protective effects of Sch B against Dox-induced cardiomyopathy in mice. Mice received a single injection of Dox (20 mg/kg IP). Five days after Dox administration, left ventricular (LV) performance was significantly depressed and was improved by Sch B treatment. Sch B prevented the Dox-induced increase in lipid peroxidation, nitrotyrosine formation, and metalloproteinase activation in the heart. In addition, the increased expression of phospho-p38 MAPK and phospho-MAPK activated mitogen kinase 2 levels by Dox were significantly suppressed by Sch B treatment. Sch B also attenuated Dox-induced higher expression of LV proinflammatory cytokines, cardiomyocyte DNA damage, myocardial apoptosis, caspase-3 positive cells and phopho-p53 levels in mice. Moreover, LV expression of NADPH oxidase subunits and reactive oxygen species were significantly less in Sch B treatment mice after Dox injection. These findings suggest that Sch B attenuates Dox-induced cardiotoxicity via antioxidative and anti-inflammatory effects.
OncoTargets and therapy, 2015
This study aimed to investigate whether the herbal formula B307 could alleviate doxorubicin (DOX)-induced acute cardiotoxicity. If so, we further unraveled possible molecular mechanisms of cardiac protection under treatment with the herbal formula B307. Before the animal experiment, we examined relative viabilities of Huh7 cancer cells under treatment with the herbal formula B307. To test whether oral treatment with the herbal formula B307 could alleviate cardiotoxicity, equal volumes of B307 (50 mg/kg) or saline (sham treatment) were administered to 20-week-old male mice once daily for 14 consecutive days. Then, DOX (10 mg/kg; ip) was administered to male mice under B307 and sham treatments at 22-23 weeks of age. Cardiac functions in these mice were assessed via echocardiography at 23-24 weeks of age. Then, expressions of oxidative stress, inflammation, and apoptosis-related proteins were examined in the heart tissue by immunohistochemistry and Western blotting at 24-25 weeks of ag...
Scholars international journal of anatomy and physiology, 2023
Doxorubicin-induced cardiotoxicity is the leading cause of morbidity and mortality among cancer survivors. The present study aimed to investigate the ameliorative effect of 5, 7-dihydroxyflavone (chrysin) against doxorubicin-induced cardiotoxicity in Wistar rats. Thirty-five adult male Wistar albino rats were randomly allocated into seven groups (n = 5 each) which consisted of normal control (group 1) receiving phosphate buffer saline (0.4 ml), positive control (Group 2) received 2mg\kg of doxorubicin (DOX) through an intraperitoneal route once weekly for 21 days, chrysin low dose and chrysin high dose (Group 3 and 4) received oral administration of chrysin 50&100mg/kg for 21 days, chrysin low dose and DOX, chrysin medium dose and DOX and chrysin high dose and DOX(group 5, 6, and 7) received 2mg/kg of DOX once weekly with 50, 100 and 150mg/kg of chrysin for 21 days. Significant elevations in cardiac troponin I (cTnI) and histological lesions, which corresponded with oxidative stress, inflammation, apoptotic indicators, and cardiotoxicity when compared to controls, were indicative of DOX-induced cardiotoxicity. Malondialdehyde (MDA), a sign of oxidative stress, SOD, CPK (creatinine phosphokinase), TBARS (thiobarbituric acid reactive substance), and CAT (catalase) were also elevated in the DOX group. The DOX group also had increased levels of cardiac inflammatory markers, including as interleukin-1 (IL-1), interleukin-6 (IL-6), and the apoptotic marker caspase-3. 5, 7-dihydroxyflavone (chrysin) significantly mitigated, but did not entirely reverse, the cardiotoxicity caused by DOX by reducing the histopathological scores of cardiomyopathies and lowering cTnI in comparison to the DOX group. Additionally, chrysin reduced MDA to substantially similar levels as the control. Following chrysin administration, significant decreases in IL-1, IL-6, and caspase-3 were also seen in comparison to the DOX-only group. All things considered, these findings point to chrysin's protective action against DOX-induced cardiotoxicity, which may have been rendered possible by oxidative stress, inflammatory, and apoptotic suppression.
Aspalathin ameliorates doxorubicin-induced oxidative stress in H9c2 cardiomyoblasts
Toxicology in Vitro, 2018
Aspalathin (ASP) is a C-dihydrochalcone abundantly found in Aspalathus linearis. While we have provide evidence that ASP can protect H9c2 cardiomyoblasts against doxorubicin (Dox)-induced apoptosis through regulation of autophagy, the complete mechanism involved in the cardioprotective effect of this dihydrochalcone remains to be explored. Here we provide evidence that ASP reverses Dox-induced apoptosis through the amelioration of oxidative stress in H9c2 cardiomyoblasts. Cultured cells were treated with 0.2 μM Dox or co-treated with either 20 μM dexrazoxane (Dexra) or 0.2 μM ASP daily for five days, to a final dose of 1 μM Dox, 100 μM Dexra and 1 μM ASP, respectively. Superoxide dismutase, catalase, glutathione, malondialdehyde and dichlorodihydro-fluorescein diacetate fluorescence were used as end-point measurements for oxidative stress, while JC-1 and TUNEL labeling were performed to assess mitochondria depolarization and apoptosis. Co-treatment with ASP attenuated Dox-induced cardiotoxicity by improving endogenous antioxidant levels and mitochondrial membrane potential, while inhibiting reactive oxygen species production and cellular apoptosis. These findings suggested that ASP can prevent Dox-induced oxidative stress and apoptosis and needs further assessment to confirm its therapeutic potential to prevent Dox-induced cardiotoxicity.
European Journal of Pharmacology, 2014
Doxorubicin (DOX) is one of the most effective chemotherapeutic drugs; however, its incidence of cardiotoxicity compromises its therapeutic index. Chrysin, a natural flavone, possesses multiple biological activities, such as antioxidant, anti-inflammatory and anti-cancer. The present study was designed to investigate whether chrysin could protect against DOX-induced acute cardiotoxicity; and if so, unravel the molecular mechanisms of this protective effect. Chrysin was administered to male albino rats once daily for 12 consecutive days at doses of 25 and 50 mg/kg orally. DOX (15 mg/kg; i.p.) was administered on day 12. Chrysin pretreatment significantly protected against DOX-induced myocardial damage which was characterized by conduction abnormalities, increased serum creatine kinase isoenzyme-MB (CK-MB), and lactate dehydrogenase (LDH) and myofibrillar disarrangement. As indicators of oxidative stress, DOX caused significant glutathione depletion, lipid peroxidation and reduction in activities of antioxidant enzymes; catalase (CAT) and superoxide dismutase (SOD). Chrysin pretreatment significantly attenuated DOX-induced oxidative injury. Additionally, DOX provoked inflammatory responses by increasing the expressions of nuclear factor kappa-B (NF-κB), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and the levels of tumor necrosis factor-alpha (TNF-α) and nitric oxide while chrysin pretreatment significantly inhibited these inflammatory responses. Furthermore, DOX induced apoptotic tissue damage by increasing Bax and cytochrome c expressions and caspase-3 activity while decreasing the expression of Bcl-2. Chrysin pretreatment significantly ameliorated these apoptotic actions of DOX. Collectively, these findings indicate that chrysin possesses a potent protective effect against DOX-induced acute cardiotoxicity via suppressing oxidative stress, inflammation and apoptotic tissue damage.
Journal of Natural Medicines, 2011
Oxidative stress has been widely implicated in the pathogenesis of hypoxia/reoxygenation (H/R) injury. San-Huang-Xie-Xin-Tang (SHXT), a widely used traditional Chinese medication, has been shown to possess antioxidant effects. Here, we investigated whether SHXT and its main component baicalin can attenuate oxidative stress induced by H/R injury. H9c2 rat ventricular cells were exposed to SHXT or baicalin followed by hypoxia for 24 h and/or reoxygenation for 8 h. Pretreatment with SHXT and baicalin both significantly prevented cell death and production of reactive oxygen species induced by hypoxia or H/R in H9c2 cardiomyoctes. In addition, SHXT and baicalin also inhibited hypoxia-or H/R-induced apoptosis, with associated decreased Bax protein, increased Bcl-2 protein, and decreased caspase-3 activity. Furthermore, we found that hypoxia and H/R decreased endothelial nitric oxide synthase (eNOS) expression and nitrite production, and these effects were counteracted by SHXT and baicalein. Finally, SHXT inhibited H/R-induced activation of p38 mitogen activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) phosphorylation in H9c2 rat ventricular cells. The present study demonstrates for the first time that SHXT can protect cardiomyocytes from H/R injury via inhibition of oxidative stress-induced apoptosis. These cardioprotective effects are possibly mediated through eNOS enhancement and p38 MAPK and JNK-dependent signaling pathways.
Cardiovascular Toxicology, 2020
Doxorubicin (DOX) is widely used as an effective chemotherapy agent in cancer treatment. Cardiac toxicity in cancer treatment with DOX demand urgent attention and no effective treatment has been established for DOX-induced cardiomyopathy. It has been well documented that human amniotic membrane proteins (AMPs), extracted from amnion membrane (AM), have antioxidant, anti-apoptotic, and cytoprotective properties. Therefore, in this study, we aimed to investigate the protective effects of AMPs against cardiotoxicity induced by DOX in cultured rat cardiomyocyte cells (H9c2). DOX-induced cell injury was evaluated using multi-parametric assay including thiazolyl blue tetrazolium bromide (MTT), the release of lactic dehydrogenase (LDH), intracellular Ca2+ , reactive oxygen species (ROS) levels, cellular antioxidant status, mitochondrial membrane potential (ΔΨm), malondialdehyde (MDA), and NF-κB p65 DNA-binding activity. Moreover, expression profiling of apoptosis-related genes (P53, Bcl-2, and Bax) and Annexin V by flow cytometry were used for cell apoptosis detection. It was shown that AMPs pretreatment inhibited the cell toxicity induced by DOX. AMPs effectively attenuated the increased levels of LDH, Ca2+ , ROS, and MDA and also simultaneously elevated the ΔΨm and antioxidant status such as superoxide dismutase (SOD) and Catalase (CAT) in pretreated H9c2 cardiomyocytes. Besides, the activity of NF-kB p65 was reduced and the p53 and Bax protein levels were inhibited in these myocardial cells subjected to DOX. These findings provide the first evidence that AMPs potently suppressed DOX-induced toxicity in cardiomyocytes through inhibition of oxidative stress and apoptosis. Thus, AMPs can be a potential therapeutic agent against DOX cardiotoxicity.
Advances in Biological Chemistry, 2014
This study was carried out to determine the possible protective effect of 1-ethyl-3-[4-(2, 2, 6, 6-tetramethylpiperidine-1-oxyl)]-1-nitrosourea (SLENU), recently synthesised in our laboratory on doxorubicin and bleomycin-induced oxidative toxicity in C57 black tumour-bearing mice. Specifically, alterations in some biomarkers of oxidative stress, such as lipid peroxidation products measured as malondialdehyde (MDA) levels and activities of the antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), were studied in lung, heart and kidney homogenates isolated from C57 black tumor-bearing mice after i.p. treatment with solutions of DOX (60 mg/kg) and BLM (60 mg/kg). The same biomarkers were also measured after i.p. pretreatment of mice with SLENU (100 mg/kg). After treatment with doxorubicin, heart and kidney homogenates of mice had significantly higher productions of lipid peroxidation compared to lung homogenates. It was accompanied by increased activity of the antioxidant defence enzyme superoxide dismutase and decreased activity of catalase. Bleomycin-induced oxidative stress was confirmed by significantly higher production of lipid peroxidation in lungs compared to heart homogenates, elevation of the antioxidant activity of superoxide dismutase and decreased activity of catalase enzymes. After pretreatment of the mice with SLENU, the levels of all studied oxidative stress biomarkers were significantly improved in comparison with those of the mice treated alone with either bleomycin, or doxorubicin. The present results and those from a previously demonstrated superoxide scavenging activities (SSA) of the nitrosourea SLENU have enabled us to explain the protective effect of the spin-labelled nitrosourea on doxorubicin and bleomycin-induced oxidative stress by scaveng-V. G. Gadjeva et al. 292 ing of • 2 O − and increased •NO release.