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Bisphenol A (BPA) is primarily used in production of polycarbonate plastics and epoxy resins including plastic containers. BPA is an endocrine disruptor and supposes to induce asthma and cancer. However, so far only a few evidences have shown the BPA-induced toxic effect and its related mechanism in macrophages. BPA demonstrated cytotoxic effect on RAW264.7 macrophages in a concentration and time-dependent manner. BPA induces necrosis, apoptosis, and genotoxicity in a concentration-dependent manner. Phosphorylation of cytochrome C (cyto C) and p53 was due to mitochondrial disruption via BCL2 and BCL-X L downregulation and BAX, BID, and BAD upregulation. Both caspase-dependent, including caspase-9, caspase-3, and PARP-1 cleavage, and caspase-independent, such as nuclear translocation of AIF, pathways were activated by BPA. Furthermore, generation of reactive oxygen species (ROS) and reduction of antioxidative enzyme activities were induced by BPA. Parallel trends were observed in the effect of BPA on cytotoxicity, apoptosis, genotoxicity, p53 phosphorylation, BCL2 family expression exchange, caspase-dependent and independent apoptotic pathways, and ROS generation in RAW264.7 macrophages. Finally, BPA-exhibited cytotoxicity, apoptosis, and genotoxicity could be inhibited by N-acetylcysteine. These results indicated that the toxic effect of BPA was functioning via oxidative stress-associated mitochondrial apoptotic pathway in macrophages., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Coronarin D, a diterpene derived from the rhizomes of Hedychium coronarium, has been used to treat inflammatory diseases. Coronarin D can exert strong anticancer effects through cell growth prevention and cell cycle arrest in many cancer cells. In this study, we investigated the molecular mechanism through which coronarin D suppresses cell proliferation and triggers cell death in human hepatocellular carcinoma (HCC) cells. Treatment of Huh7 and Sk-hep-1 cells with coronarin D resulted in a significantly increased loss of mitochondrial membrane potential, leading to the cleavage and activation of caspase-9, caspase-8, and caspase-3 and changes in Bax, Bcl-2, and Bcl-xL protein levels. Coronarin D significantly induced autophagy by increasing the expression of Beclin-1 and LC3-II and reducing the expression of p62. Moreover, Huh7 and Sk-hep-1 cells exposed to coronarin D had decreased expression of phosphorylated AKT, p38, and ERK and increased expression of phosphorylated JNK. Exposure of cells to the JNK-specific inhibitor SP600125 attenuated the apoptotic effects of coronarin D. Taken together, this is the first study to report that coronarin D may effectively inhibit cell growth through apoptosis. We have provided evidence indicating that coronarin D induces cell death through the upregulation of JNK mitogen-activated protein kinases in human HCC cells., (© 2018 Wiley Periodicals, Inc.)

Fisetin, a diatery flavonoid, been reported that possess anticancer effects in various cancers. The purpose of the study was to investigate the antitumor effects of fisetin in cultured uveal melanoma cell lines and compared with normal retinal pigment epithelial (RPE) cells. MTT assay was used for evaluating cytotoxic effects of fisetin. Flow cytometry study was used for the determination of apoptosis. JC-1 fluorescent reader was used to determine mitochondrial transmembrane potential changes. The results shown that fisetin dose-dependently decreased the cell viability of uveal melanoma cells but not influenced the cell viability of RPE cells. Apoptosis of uveal melanoma cells was induced by fisetin efficiently. Fisetin inhibited antiapoptotic Bcl-2 family proteins and damaged the mitochondrial transmembrane potential. The levels of proapoptotic Bcl-2 proteins, cytochrome c, and various caspase activities were increased by fisetin. In conclusion, fisetin induces apoptosis of uveal melanoma cells selectively and may be a promising agent to be explored for the treatment of uveal melanoma., (© 2018 Wiley Periodicals, Inc.)

Previous studies showed that NaIO3 can induce oxidative stress-mediated retinal pigment epithelium (RPE) damage to simulate age-related macular degeneration (AMD). Lemon peel is rich in antioxidants and components that can penetrate the blood–retinal barrier, but their role in retinal oxidative damage remains unexplored. Here, we explore the protection of lemon peel ultrasonic-assisted water extract (LUWE), containing large amounts of flavonoids and polyphenols, against NaIO3-induced retinal degeneration. We initially demonstrated that LUWE, orally administered, prevented retinal distortion and thinning on the inner and outer nuclei layers, downregulating cleaved caspase-3 protein expression in RPE cells in NaIO3-induced mice. The effect of LUWE was achieved through the suppression of apoptosis and the associated proteins, such as cleaved PARP and cleaved caspase-3, as suggested by NaIO3-induced ARPE-19 cell models. This is because LUWE reduced reactive oxygen species-mediated mitochondrial fission via regulating p-Drp-1 and Fis1 expression. We further confirmed that LUWE suppresses the expression of p-MEK-1/2 and p-ERK-1/2 in NaIO3-induced ARPE-19 cells, thereby providing the protection described above, which was confirmed using PD98059 and U0126. These results indicated that LUWE prevents mitochondrial oxidative stress-mediated RPE damage via the MEK/ERK pathway. Elucidation of the molecular mechanism may provide a new protective strategy against retinal degeneration. [ABSTRACT FROM AUTHOR]

Lead (Pb) is nonbiodegradable and toxic to the lungs. To investigate the potential mechanisms of Pb‐induced reactive oxygen species (ROS) accumulation and cell death in the lungs, human non‐small lung carcinoma H460 cells were stimulated with Pb(NO3)2 in this study. The results showed that Pb(NO3)2 stimulation increased cell death by inducing cell apoptosis which showed a reduced Bcl‐2 expression and an enhanced caspase 3 activation. Pb(NO3)2 also caused the production of H2O2 in H460 cells that triggering the buildup of ROS and mitochondrial membrane potential loss. We found that Pb(NO3)2 modulates oxidoreductive activity through reduced the glutathione‐disulfide reductase and glutathione levels in Pb(NO3)2‐exposed H460 cells. Furthermore, the superoxide dismutase (SOD) upstream molecule sirtuin 3 (SIRT3) was increased with Pb(NO3)2 dose. Collectively, these results demonstrate that Pb(NO3)2 promotes lung cell death through SIRT3/SOD‐mediated ROS accumulation and mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

Background: Laboratory studies have demonstrated statin-induced apoptosis of cancer cells, including breast cancer cells, and evidence is accumulating on the mechanism of statin-induced apoptosis. However, despite numerous epidemiological studies, no consensus has been reached regarding the relationship between statin use and breast cancer risk. Methods: This retrospective case-control study enrolled 4332 breast cancer patients and 21,660 age-matched controls registered in the National Health Insurance program of Taiwan, which covers approximately 99% of the population. The study cases were women for whom a diagnosis of breast cancer (ICD-9-CM code 174.X) had been recorded in LHID2005 between January 1, 2004 and December 31, 2010. A logistic regression model was adjusted for potential confounding factors, including the level of urbanization, and the Charlson Comorbidity Index was applied to assess potential comorbidities. We also considered possible bias caused by random urbanization, because nutrition and lifestyle factors are related to breast cancer incidence. Results: Our results showed that lovastatin was associated with a lower risk of breast cancer (adjusted OR 0.596; 95% CI 0.497-0.714; p < 0.001), and atorvastatin exhibited a protective tendency against breast cancer (adjusted OR 0.887; 95% CI 0.776-1.013; p < 0.077). Conclusions: Although no consensus has been established regarding the relationship between statin use and breast cancer risk, our study indicated that lovastatin is a potential chemopreventive agent against breast cancer. Further detailed research is warranted. [ABSTRACT FROM AUTHOR]

It is well known that age-related macular degeneration (AMD) is an irreversible neurodegenerative disease that can cause blindness in the elderly. Oxidative stress-induced retinal pigment epithelial (RPE) cell damage is a part of the pathogenesis of AMD. In this study, we evaluated the protective effect and mechanisms of alpha-mangostin (α-mangostin, α-MG) against NaIO3-induced reactive oxygen species (ROS)-dependent toxicity, which activates apoptosis in vivo and in vitro. MTT assay and flow cytometry demonstrated that the pretreatment of ARPE-19 cells with α-MG (0, 3.75, 7.5, and 15 μM) significantly increased cell viability and reduced apoptosis from NaIO3-induced oxidative stress in a concentration-dependent manner, which was achieved by the inhibition of Bax, cleaved PARP-1, cleaved caspase-3 protein expression, and enhancement of Bcl-2 protein. Furthermore, pre-incubation of ARPE-19 cells with α-MG markedly inhibited the intracellular ROS and extracellular H2O2 generation via blocking of the abnormal enzyme activities of superoxide dismutase (SOD), the downregulated levels of catalase (CAT), and the endogenous antioxidant, glutathione (GSH), which were regulated by decreasing PI3K-AKT-PGC-1α-STRT-3 signaling in ARPE-19 cells. In addition, our in vivo results indicated that α-MG improved retinal deformation and increased the thickness of both the outer nuclear layer and inner nuclear layer by inhibiting the expression of cleaved caspase-3 protein. Taken together, our results suggest that α-MG effectively protects human ARPE-19 cells from NaIO3-induced oxidative damage via antiapoptotic and antioxidant effects. [ABSTRACT FROM AUTHOR]

Age-related macular degeneration (AMD) leads to gradual central vision loss and is the third leading cause of irreversible blindness worldwide. The underlying mechanisms for this progressive neurodegenerative disease remain unclear and there is currently no preventive treatment for dry AMD. Sodium iodate (NaIO3) has been reported to induce AMD-like retinal pathology in mice. We established a mouse model for AMD to evaluate the effects of quercetin on NaIO3-induced retinal apoptosis, and to investigate the pertinent underlying mechanisms. Our in vitro results indicated that quercetin protected human retinal pigment epithelium (ARPE-19) cells from NaIO3-induced apoptosis by inhibiting reactive oxygen species production and loss of mitochondrial membrane potential as detected by Annexin V-FITC/PI flow cytometry. We also evaluated the relative expression of proteins in the apoptosis pathway. Quercetin downregulated the protein expressions of Bax, cleaved caspase-3, and cleaved PARP and upregulated the expression of Bcl-2 through reduced PI3K and pAKT expressions. Furthermore, our in vivo results indicated that quercetin improved retinal deformation and increased the thickness of both the outer nuclear layer and inner nuclear layer, whereas the expression of caspase-3 was inhibited. Taken together, these results demonstrate that quercetin could protect retinal pigment epithelium and the retina from NaIO3-induced cell apoptosis via reactive oxygen species-mediated mitochondrial dysfunction, involving the PI3K/AKT signaling pathway. This suggests that quercetin has the potential to prevent and delay AMD and other retinal diseases involving NaIO3-mediated apoptosis. [ABSTRACT FROM AUTHOR]

Urethane dimethacrylate (UDMA) is a dimethacrylate-based resin monomer that can react with other related monomers and inorganic particles, causing hydrophobic polymerization through cross-linking upon light activation. UDMA polymers are commonly used for the reconstruction and reinforcement of teeth and bones. UDMA can become unbound and be released from light-cured polymer resins. Thus far, no evidence exists on the toxic effects of UDMA and its related working mechanisms for macrophages. Therefore, in the present study, we investigated the cytotoxicity, mode of cell death, DNA damage, caspase activities, mitochondrial dysfunction, and reactive oxygen species (ROS) generation in RAW264.7 macrophages treated with UDMA using the lactate dehydrogenase (LDH) assay kit, Annexin V-FITC and PI assays, micronucleus formation and comet assay, caspase fluorometric assay, JC-1 assay, and 2ʹ,7ʹ-dichlorofluorescin diacetate (DCFH-DA) assay, respectively. Our results show that UDMA induced cytotoxicity; apoptosis and necrosis; genotoxicity, which is also called DNA damage; increased caspase-3, -8, and -9 activities; mitochondrial dysfunction; and intracellular ROS generation in a concentration-dependent manner in RAW264.7 macrophages. Thus, based on the observed inhibited concentration parallel trends, we concluded that UDMA induces toxic effects in macrophages. Furthermore, UDMA-induced intracellular ROS generation, cytotoxicity, and DNA damage were reduced by N-acetyl-L-cysteine. [ABSTRACT FROM AUTHOR]