Novel antioxidants' synthesis and their anti-oxidative activity through activating Nrf2 signaling pathway.

Novel structure compounds (WS) containing 3,4,5-trimethoxyphenyl and acyl pyrazole were designed and synthesized based combination principles. Among them, WS13 was screened out to possess desirable anti-oxidative activity in vitro. Cell survival assay and apoptosis experiment in H2O2 induced PC12 cells injury model all showed that its cytoprotection exhibited a concentration-effect manner. WS13 at 10µM could remove ROS with equal effiency to edaravone. Further, it clearly activated Nrf2 nuclear translocation and upregulated GCLC mRNA transcription and protein expression in dose-dependent manner, and its cytoprotection was reversed by GCLC protein inhibitor. In total, WS13 with further promotion can serve as Nrf2-GCLC activator in anti-oxidative therapy.

Synthetic chalcones with potent antioxidant ability on H2O2-induced apoptosis in PC12 cells.

Chalcone derivatives (E)-3-(4-hydroxy-3-methoxyphenyl)-1-(4-methoxyphenyl) prop-2-en-1-one and (E)-3-(4-hydroxyphenyl)-1-(4-methoxyphenyl) prop-2-en-1-one (Compounds 1 and 2) have been demonstrated to be potent anti-inflammatory agents in our previous study. In light of the relationship of intracellular mechanisms between anti-inflammatories and antioxidants, we further designed and synthesized a series of chalcone derivatives based on 1 and 2, to explore their antioxidant efficacy. The majority of the derivatives exhibited strong protective effects on PC12 (PC12 rat pheochromocytoma) cells exposed to H2O2, and all compounds were nontoxic. A preliminary structure-activity relationship was proposed. Compounds 1 and 1d ((E)-2-methoxy-4-(3-(4-methoxyphenyl)-3-oxoprop-1-en-1-yl) phenyl acrylate) exerted the action in a good dose-dependent manner. Quantitative RT-PCR (qRT-PCR) and western blot analysis showed that 1 and 1d significantly improve the expression of nuclear factor erythroid 2 p45-related factor 2 (Nrf2)-dependent antioxidant genes g-Glutamylcysteine Ligase Catalytic Subunit (GCLC) and heme oxygenase-1 (HO-1) and their corresponding proteins (γ-glutamyl cysteine synthase (γ-GCS) and HO-1) in PC12 cells. Inhibition of GCLC and HO-1 by specific inhibitors, L-buthionine-S-sulfoximine (BSO) and zinc protoporphyrin (ZnPP), respectively, partially reduce the protective effect of 1 and 1d. These data present a series of novel chalcone analogs, especially compounds 1 and 1d, as candidates for treating oxidative stress-related disease by activating the Nrf2-antioxidant responsive element (ARE) pathway.

Design, synthesis, and evaluation of NDGA analogues as potential anti-ischemic stroke agents.

Exogenous supplementation of antioxidants with ROS scavenging activity would be a potential therapy to cerebral ischemia-reperfusion injury in stroke. In the present study, a series of NDGA analogues with attenuation oxidative stress by directly scavenging ROS and indirectly through keap1/Nrf2/ARE pathway activation were designed and synthesized. All analogues were found to effectively remove ROS directly by DPPH radical scavenging assay, and compound 3a conferred potent protection from the oxidative injury in PC12 cells via promoting Nrf2 to translocate into nucleus and increasing expression of heme oxygenase-1(HO-1), where strongly reduced intracellular ROS level indirectly. More importantly, 3a significantly reduced brain infarction after cerebral ischemia-reperfusion injury in rats subjected to transient middle cerebral artery occlusion (MCAO). Overall, our findings shown compound 3a could serve as a promising compound for the treatment of stroke.

Design, synthesis, and evaluation of asymmetric EF24 analogues as potential anti-cancer agents for lung cancer.

The nuclear factor-kappa B (NF-κB) signaling pathway has been targeted for the therapy of various cancers, including lung cancer. EF24 was considered as a potent inhibitor of NF-κB signaling pathway. In this study, a series of asymmetric EF24 analogues were synthesized and evaluated for their anti-cancer activity against three lung cancer cell lines (A549, LLC, H1650). Most of the compounds exhibited good anti-tumor activity. Among them, compound 81 showed greater cytotoxicity than EF24. Compound 81 also possessed a potent anti-migration and anti-proliferative ability against A549 cells in a concentration-dependent manner. Moreover, compound 81 induced lung cancer cells death by inhibiting NF-κB signaling pathway, and activated the JNK-mitochondrial apoptotic pathway by increasing reactive oxygen species (ROS) generation resulting in apoptosis. In summary, compound 81 is a valuable candidate for anti-lung cancer therapy.