mTOR is a highly conserved Ser/Thr kinase, which integrates diverse signals to control cell growth, proliferation, survival and metabolism. mTOR assembles into two functionally different complexes, mTORC1 and mTORC2, with distinct inputs and downstream effects. mTORC1 regulates cell growth by promoting translation, ribosome biogenesis and autophagy via phosphorylation of its substrates, including 4E-BP1 and ribosomal S6K. mTORC2 promotes cell cycle entry, cell survival, actin cytoskeleton polarization and anabolic output though phosphorylation of its substrates, the Ser/Thr protein kinases, Akt, protein kinase A (PKA) and PKC ( 10 , 11 ). Previous findings demonstrate that aberrant activation of the mTOR signaling pathway is vital in tumorigenesis, and promotes growth and survival of various types of cancer cells ( 12 ). Due to its high biological relevance to cancer, different therapeutic strategies have been developed to target this signaling cascade, such as mTOR inhibitors Everolimus and Temsirolimus ( 13 ). In the current study, the activation levels of the mTOR signaling pathway during HNK-triggered regulated necrosis in HEK-293 cells was determined. Western blot analysis was performed to determine the phosphorylation and expression levels of core mTOR substrates, Akt, 4E-BP1 and S6K. The phosphorylation levels of 4E-BP1 and S6K were observed to gradually decline with the elongation of incubating duration (, , 1 and 2 h) during the process of HNK-triggered regulated necrosis. Phosphorylation of Akt on Thr308 and Ser473 were also gradually downregulated. Conversely, the protein expression levels of Akt, 4E-BP1 and S6K were stable ( Fig. 8A ). Figs. 5 and 6 demonstrate that CsA markedly inhibited HNK-induced regulated necrosis. Therefore whether pretreatment with CsA could reverse dephosphorylation of mTOR substrates was investigated. Pretreatment with CsA prominently reversed dephosphorylation of Akt on Ser473, however, only partially reversed dephosphorylation of 4E-BP1, S6K and Akt on Thr308 ( Fig. 8B ). Collectively, the above results reveal that the mTOR signaling pathways were inhibited during the process of HNK-triggered regulated necrosis in HEK-293 cells. Furthermore, CypD may act downstream of mTOR signaling pathways, as CsA blocked HNK-triggered regulated necrosis, although it only partially reversed the dephosphorylation of mTOR substrates.
(UPLC) method for the determination of four plant sterols (rapeseed sterols, stigmasterol, campesterol, β-sitosterol) in edible vegetable The edible vegetable oil samples were saponified and adjusted with glacial acetic acid PH = ~ . After centrifugation with ethanol, the supernatant was centrifuged and the elution was carried out using Endoavorsil C18 column (100 mm × mm, μm) using methanol as mobile phase equilibration, and using a diode array detector The results showed that the linear range of β-sitosterol, stigmasterol and rapeseed sterols was 20-200 μg / ml, and that of campesterol was 10-100 μg / ml. The correlation coefficients r were all greater than 9. The limits of detection (S / N = 3) were: rapeseed sterols, stigmasterol, campesterol and β-sitosterol, respectively, , , and μg / g; The relative standard deviations RSD (n = 6) were <3%. The recoveries of the four components were % -% at the three levels of high, medium and low concentrations. Conclusion This method is simple, accurate and sensitive. It is suitable for simultaneous determination of four major phytosterols in edible vegetable oil.
It contains a rich source of carotenoids, triterpenoids and ascorbic acid. Compounds that act as receptor antagonists of glucocorticoids have reduced the healing time of broken bones 30 to 50 percent in clinical trials. It has also been used to treat obesity and associated oxidative bactericidal effects on Helicobacter pylori hold promise as an effective treatment of gastric ulcers and preventative of stomach cancer in conjunction with NSAID therapy.