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Endothelial cell injury in vascular arterial walls is a hallmark of atherosclerosis. Pterostilbene (Pts) has been shown to have an anti-oxidative and anti-apoptotic effect in numerous diseases via regulation of intracellular metabolism. The purpose of this study was to investigate the protective effect and possible mechanism of Pts against endothelial cell apoptosis in an atherosclerotic rat model. An atherosclerotic rat model was established using a high-fat, high glucose and high cholesterol diet. The effects of Pts on apoptosis and oxidative stress injury were measured using atherosclerotic lesion analysis, western blot analysis, hematoxylin and eosin straining, TUNEL assay and immunohistochemistry. In vivo results in an atherosclerosis rat model showed that Pts administration decreased the inflammatory response. Pts administration attenuated atherogenesis, reduced aortic plaque size, reduced macrophage infiltration, and suppressed oxidative stress and apoptosis of vascular arterial walls. In vitro assays using cultured human endothelial cells showed that Pts administration decreased hydrogen peroxide-induced cytotoxicity, oxidative stress injury and apoptosis via nuclear factor erythroid 2-related factor 2 (Nrf2) activation in endothelial cells. Additionally, Pts administration increased the expression level of Nrf2 and 5′ adenosine monophosphate-activated protein kinase (AMPK), and the phosphorylation level of AMPK and decreased signal transducer and activator of transcription 3 (STAT3) expression in these cells. Furthermore, knockdown of Nrf2 prevented Pts-decrease oxidative stress injury and apoptosis. In conclusion, these data suggest that Pts can protect endothelial cells in the vascular arterial walls against atherosclerosis-induced injury through regulation of the Nrf2-mediated AMPK/STAT3 pathway. [ABSTRACT FROM AUTHOR]

Central neurocytoma (CN) is a rare periventricular tumor of the central nervous system in young adults. Typically, patients with CN exhibit a favorable prognosis, but in certain cases the clinical course is more aggressive. Therefore, investigating effective therapeutic approaches is important. Oridonin has attracted attention due to its antitumor activities. However, the role of oridonin in tumorigenesis and progression remains unknown. The present study examined the antitumor function of oridonin in CN cells, and investigated the underlying molecular mechanism. An MTT assay suggested that treatment with oridonin was able to significantly inhibit the proliferation of CN cells. The annexin V‑fluorescein isothiocyanate/propidium iodide assay and western blot analysis demonstrated that oridonin was able to induce apoptosis and alter the expression of apoptosis‑associated proteins by downregulating anti‑apoptotic protein, B‑cell lymphoma‑2 (Bcl‑2), and upregulating pro‑apoptosis proteins, Bcl‑2‑like protein 4, cleaved caspase‑3 and cleaved poly(ADP‑ribose) polymerase 1. Subsequently, the Wnt/β‑catenin signaling pathway was examined. Western blot analysis indicated that oridonin markedly decreased the expression of β‑catenin, cyclin D1 and v‑myc avian myelocytomatosis viral oncogene homolog. Furthermore, β‑catenin was silenced by small interference RNA or overexpressed in CN cells, and the effect on cell proliferation was examined. The results indicated that silencing of β‑catenin enhanced the inhibitory effect of oridonin on cell growth, whereas the overexpression of β‑catenin attenuated this effect. These data indicated that oridonin inhibited proliferation and induced apoptosis to exert its antitumor activity in CN cells by repressing Wnt/β‑catenin signaling. Therefore, the present study suggested that oridonin might be an effective adjuvant agent, and that the Wnt/β‑catenin signaling pathway may be a potent target for the therapy in CN. [ABSTRACT FROM AUTHOR]

Neuroblastoma, one of the most common types of cancer in childhood, is commonly treated with surgery, radiation and chemotherapy. However, prognosis and survival remain poor for children with high-risk neuroblastoma. Therefore, the identification of novel, effective therapeutic targets is necessary. N-Myc, a proto-oncogene protein encoded by the v-myc avial myelocytomatosis viral oncogene neuroblastoma derived homolog (MYCN) gene, is associated with tumorigenesis. In the present study, the effect of N-Myc silencing on MYCN-amplified CHP134 and BE-2C neuroblastoma cells was evaluated, and the underlying molecular mechanism was investigated. N-Myc was successfully knocked down using an N-Myc-specific small interfering RNA, the efficacy of interference efficiency confirmed by reverse transcription-quantitative polymerase chain reaction and western blotting. Cell viability was evaluated by MTT assay and apoptosis was measured by ELISA assay. The results indicated that MYCN silencing significantly decreased cell viability and promoted apoptosis. Subsequently, the expression levels of key Wnt/β-catenin signaling pathway proteins were detected by western blotting, and MYCN silencing was demonstrated to inhibit Wnt/β-catenin signaling, decreasing the expression ofanti-apoptosis proteins and increasing the expression of pro-apoptosis protein. This suggested that N-Myc regulated survival and growth of CHP134 and BE-2C neuroblastoma cells, potentially through Wnt/β-catenin signaling. Furthermore, associated proteins, N-Myc and STAT interactor and dickkopf Wnt signaling pathway inhibitor 1, were demonstrated to be involved in this regulation. Therefore, N-Myc and its downstream targets may provide novel therapeutic targets for the treatment of neuroblastoma. [ABSTRACT FROM AUTHOR]