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Hesperetin (HSP) is a natural flavonoid that offers useful curative effects for cardiovascular diseases, but its effect on myocardial ischemia and its precise mechanism remains unclear. The aim of this study is to explore the potential cardioprotective mechanism of HSP on myocardial ischemia caused by isoproterenol (ISO). Adult male Kunming mice were randomly divided into five groups: control, ISO, low-dose HSP (L-HSP, 25 mg/kg/d), high-dose HSP (H-HSP, 50 mg/kg/d), and verapamil (VER) group. Treatment groups of mice received HSP or VER for seven days, and the groups other than the control group were injected with ISO (100 mg/kg/d) subcutaneously for two consecutive days to establish a model of myocardial ischemia. Electrocardiogram and heart-histology changes were used to assess changes in myocardial architecture. The activities and the content of oxidative stress markers and inflammatory cytokines were determined and assayed using kits respectively. The expressions of proteins associated with apoptosis and the Sirt1/Nrf2 pathway were evaluated by Western blotting. The results demonstrate that VER, L-HSP and H-HSP significantly reduced the J-point displacement, heart rate, cardiac pathomorphological changes, and the levels of creatine kinase, lactated dehydrogenase, malonaldehyde, interleukin-6, and tumor necrosis factor-α in serum while promoting the activation of superoxide dismutase, catalase, glutathione in serum in the ISO-treated animals. Furthermore, L-HSP and H-HSP also reversed the ISO-induced apoptosis and the changes in the Sirt1/Nrf2 signaling pathway, as evident from the levels of proteins Bax, Bcl-2, caspase-3, Sirt1, Nrf2, NQO-1, and HO-1. In conclusion, HSP plays a protective role in ISO-induced myocardial ischemia by modulating oxidative stress, inflammation, and apoptosis via Sirt1/Nrf2 pathway activation. [Display omitted] • Hesperetin attenuates oxidative stress, inflammation, and apoptosis in mouse heart. • Hesperetin activates the expression of the Sirt1/Nrf2 pathway. • Hesperetin has a protective action on isoproterenol-induced myocardial ischemia. [ABSTRACT FROM AUTHOR]

• Crocetin attenuates oxidative stress, inflammation and apoptosis in the kidney. • Crocetin activates the expression of the PI3K/AKT pathway related genes. • Crocetin has a protective action on arsenic trioxide-induced nephrotoxicity. Arsenic trioxide (ATO)-induced renal toxicity through oxidative stress and apoptosis restricts the therapeutic action of acute myelogenous leukemia. Crocetin (Crt) possesses antioxidant and antiapoptosis properties, and has certain renal protective effects, but it has not been reported that it has protective effect on renal injury caused by ATO. The current study explored the effects and mechanisms of Crt on kidney damage induced by ATO. Fifty Sprague-Dawley rats were randomly divided into five groups. Adult rats were given Crt concurrently with ATO for 1 week. On the 8th day, rats were killed and blood and kidney tissues were collected. Histopathological changes were measured, and kidney tissues and serum were used to determine renal function and antioxidant enzyme activity. In addition, the protein expression levels of P-PI3K, PI3K, P-AKT, AKT, CytC, Bax, Bcl-2 and Caspase-3 were determined via western blot analysis. Results revealed ATO induced renal morphological alterations and activated serum BUN and CRE. Compared with the control group, ROS, MDA, IL-1β, TNF-α, protein carbonyls (PC), lipid hydroperoxides (LOOH) and arsenic concentration levels were found to be significantly increased and SOD, CAT, GSH-Px, GSH and total sulphydryl groups (TSH) levels were attenuated in the ATO group. Crt markedly reduced oxidative stress in ATO-induced nephrotoxicity. Further, ATO induced apoptosis by significantly enhancing CytC, Bax and Caspase-3 and inhibiting Bcl-2. Administration with Crt markedly improved the expression of apoptosis factor. Moreover, Crt treatment stimulated the expressions of P-PI3K, PI3K, P-AKT, AKT induced by ATO. This study indicates Crt could prevent renal injury caused by ATO through inhibiting oxidative stress, inflammation and apoptosis, and its mechanism may be related to activation of PI3K/Akt signaling pathway. [ABSTRACT FROM AUTHOR]

Arsenic trioxide (ATO)-induced hepatotoxicity limits the therapeutic effect of acute myelogenous leukemia treatment. Magnesium isoglycyrrhizinate (MgIG) is a natural compound extracted from licorice and a hepatoprotective drug used in liver injury. It exhibits anti-oxidant, anti-inflammatory and anti-apoptotic properties. The aim of the present study was to identify the protective action and underlying mechanism of MgIG against ATO-induced hepatotoxicity. A total of 50 mice were randomly divided into five groups (n=10/group): Control; ATO; MgIG and high- and low-dose MgIG + ATO. Following continuous administration of ATO for 7 days, the relative weight of the liver, liver enzyme, histological data, antioxidant enzymes, pro-inflammatory cytokines, cell apoptosis and changes in Kelch-like ECH-associated protein 1/nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) signaling pathway were observed. MgIG decreased liver injury, decreased the liver weight and liver index, inhibited oxidative stress and decreased the activity of glutathione, superoxide dismutase and catalase, production of reactive oxygen species and levels of pro-inflammatory cytokines, including IL-1β, IL-6 and TNF-α. Western blotting showed a decrease in Bax and caspase-3. There was decreased cleaved caspase-3 expression and increased Bcl-2 expression. MgIG notably activated ATO-mediated expression of Keap1 and Nrf2 in liver tissue. MgIG administration was an effective treatment to protect the liver from ATO-induced toxicity. MgIG maintained the level of Nrf2 in the liver and protected the antioxidative defense system to attenuate oxidative stress and prevent ATO-induced liver injury. [ABSTRACT FROM AUTHOR]

Zuotais regarded as the king of Tibetan medicine. However, the major starting material ofZuotais mercury, which is one very toxic heavy metal. This has aroused serious doubts on the biosafety ofZuotacontaining drugs. In this study, we quantified the Hg contents in fourZuotasamples, monitored the release of Hg in simulated gastric/intestinal juice and evaluated their cytotoxicity to Caco-2 cells. Our results showed that the Hg contents inZuotasamples were in the range of 566–676 mg/g. Fortunately, the release of Hg fromZuotasamples was very low in simulated gastric juice, and much lower in simulated intestinal juice. Direct contact ofZuotawith Caco-2 cells led to dose-dependent cytotoxicity, including activity loss and membrane leakage. The toxicity was closely related to apoptosis, because the caspase 3/7 levels of Caco-2 cells increased after the exposure toZuota. Interestingly,Zuotasamples inhibited the oxidative stress at low concentrations, but the toxicity could be relived by antioxidants. The possible toxicity should be attributed to the cellular uptake ofZuotaparticulates. Beyond the cytotoxicity, significant differences amongZuotasamples from different institutions were observed, suggesting that the preparation process ofZuotahad meaningful influence of its biosafety. The implications to the safety and clinical applications ofZuotaare discussed. [ABSTRACT FROM PUBLISHER]

Recent study suggests that auranofin (AF), a US Food and Drug Administration (FDA)-approved drug for treatment of rheumatoid arthritis, has selective anticancer activity in various experimental models. Its clinical applications in cancer treatment, however, have been hampered due in part to its relatively moderate activity as a single agent. In this study, we performed a high-throughput screening of the FDA-approved drug library for clinical compounds that potentiate the anticancer activity auranofin, and unexpectedly identified an anti-inflammatory drug celecoxib (CE) that potently enhanced the therapeutic activity of AF in vitro and in vivo. Mechanistically, AF/CE combination induced severe oxidative stress that caused ROS-mediated inhibition of hexokinase (HK) and a disturbance of mitochondrial redox homeostasis, resulting in a significant decrease of ATP generation. The CE-induced ROS increase together with AF-medicated inhibition of thioredoxin reductase cause a shift of Trx2 to an oxidized state, leading to degradation of MTCO2 and dysfunction of the electron transport chain. Our study has identified a novel drug combination that effectively eliminates cancer cells in vivo. Since AF and CE are FDA-approved drugs that are currently used in the clinic, it is feasible to translate the findings of this study into clinical applications for cancer treatment. [ABSTRACT FROM AUTHOR]