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In this study, a new flavonolignan vernicilignan A was isolated from Toxicodendron vernicifluum. The neuroprotective effects of this compound against H 2 O 2 induced cell injury in SH-SY5Y cells were evaluated by MTT assay and LDH release assay. Vernicilignan A dose-dependently attenuated the cell injury and LDH release induced by H 2 O 2 in SH-SY5Y cells. Further study indicated that vernicilignan A reduced cell apoptosis caused by H 2 O 2 treatment via regulation of some apoptotic related proteins including Bax, Bcl-2, caspase 3 and caspase 9. Also, vernicilignan A increase the cell viability of H 2 O 2 treated cells via the activation of Akt and GSK3β. Base on the findings, vernicilignan A exhibited neuroprotective effects through the activation of PI3K/Akt signaling and inhibition of mitochondria apoptosis pathway. Vernicilignan A might be a promising therapeutic agent for oxidative stress induced neurodegenerative diseases. Unlabelled Image [ABSTRACT FROM AUTHOR]

The ent-kaurane diterpenoid enriched fraction (EDEF) of maize root was isolated and purified, and 10 compounds, including 4 ent-kaurane diterpenoids, were isolated and identified. We evaluated their neuroprotective properties in vitro for the first time using an H 2 O 2 -induced oxidative damage model in SH-SY5Y cells. The results showed that pretreatment with maizediterpene D, a new ent-kaurane diterpenoid isolated from the EDEF, significantly attenuated H 2 O 2 -induced apoptosis by improving cell survival, reducing ROS production and increasing mitochondrial membrane potential. Mechanistically, the neuroprotective effect of maizediterpene D was confirmed to be related to the dual activation of IGF-1R and BDNF/TrkB crosstalk pathways. Our findings suggest that the EDEF and its active constituent maizediterpene D had good neuroprotective properties and could serve as potential candidates for the development of therapeutic drugs for oxidative stress-related diseases. [Display omitted] • EDEF and Maizediterpene D were isolated from maize roots. • EDEF showed good antioxidant activity against H 2 O 2 induced oxidative stress. • D showed better cytoprotective activity against H 2 O 2 triggered oxidative stress. • M-D attenuated H 2 O 2 induced oxidative stress by BDNF/TrkB and BDNF/TrkB crosstalk pathways [ABSTRACT FROM AUTHOR]

Anhua dark tea known as the earliest produced Chinese dark tea, has been commercially available and famous for its unique flavor and health care effect. NMDA receptors are glutamate-coupled ion channels that critically involved in survival of neuronal cells and neurodegenerative diseases. Thus, it is considered a promising target for the therapy of neurodegenerative disease. In this study, four catechins including two new catechins derivatives (1 – 2), together with thirteen known flavonoids were isolated from Anhua dark tea. The structures of compounds 1 – 2 [2 S ,3 R -6-methoxycarbonylgallocatechin (1) and 2 R ,3 R -6-methoxycarbonylgallocatechin (2)] were determined on the basis of their spectroscopic data. The preliminary bioassay indicated that compound 1 showed the best neuroprotective effects via N -methyl- d -aspartate (NMDA) receptors inhibition. Compound 1 protected SH-SY5Y cells against NMDA-induced injury and cell apoptosis via the modulation of NR2B expression, the activation of PI3K/Akt signaling and caspase-dependent pathway. The results suggested compound 1 would be a potent dietary therapy reagent for prevention of excitable brain injury. Unlabelled Image [ABSTRACT FROM AUTHOR]

The acquired resistance to gefitinib limits its clinical application. Epigallocatechin-3-gallate (EGCG) has been found to enhance the efficacy of gefitinib against resistant. However, the cellular and molecular mechanisms have not been completely illuminated in NSCLC. In this study, a new epigallocatechin gallate derivative (2R,3R-6-methoxycarbonylgallocatechin-3- O -gallate, the following referred to as EGCGD) (1) and three known epigallocatechin gallate compounds including epicatechin-3- O -gallate (2), gallocatechin-3- O -gallate (3) and epigallocatechin-3- O -gallate (4 , EGCG) were isolated and identified from Anhua dark tea. The pharmacological studies showed EGCGD was more effective against gefitinib-resistant HCC827-Gef cells compared to that of other three epigallocatechin gallate compounds including EGCG, suggesting that introduction of 6-methoxycarbonyl to EGCG might enhance its antitumor activities. Further study on molecular mechanism showed EGCGD increased the potency of gefitinib against HCC827-Gef cells via suppression of epithelial-Mesenchymal transition (EMT) and dual inhibition of PI3K/mTOR. Unlabelled Image [ABSTRACT FROM AUTHOR]