Design, synthesis, and evaluation of 2,2'-bipyridyl derivatives as bifunctional agents against Alzheimer's disease.

Alzheimer's disease (AD) is a complex multifactorial neurodegenerative disease. Metal ion dyshomeostasis and Aß aggregation have been proposed to contribute to AD progression. Metal ions can bind to Aß and promote Aß aggregation, and ultimately lead to neuronal death. Bifunctional (metal chelation and Aß interaction) compounds are showing promise against AD. In this work, eleven new 3,3'-diamino-2,2'-bipyridine derivatives 4a-4k were synthesized, and evaluated as bifunctional agents for AD treatment. In vitro Aß aggregation inhibition assay confirmed that most of the synthesized compounds exhibited significant self-induced Aß1-42 aggregation inhibition. Among them, compound 4d displayed the best inhibitory potency of self-induced Aß1-42 aggregation with IC50 value of 9.4 µM, and it could selectively chelate with Cu2+ and exhibited 66.2% inhibition of Cu2+-induced Aß1-42 aggregation. Meanwhile, compound 4d showed strong neuroprotective activity against Aß1-42 and Cu2+-treated Aß1-42 induced cell damage. Moreover, compound 4d in high dose significantly reversed Aß-induced memory impairment in mice.

[Differences in chemical components in processing of dried ginger-steamed, sand-fried, and rice swill water-bleached Aconiti Lateralis Radix Praeparata pieces in "Jianchang" faction based on UPLC-MS/MS].

This study compared the changes in chemical components during the processing of different types of Aconiti Lateralis Radix Praeparata(ALRP) in "Jianchang" faction, i.e., dried ginger-steamed ALRP pieces(Yin-FP), sand-fried ALRP pieces(Yang-FP), and rice swill water-bleached ALRP pieces(DFP), and provided a scientific basis for the mechanism in toxicity reduction and efficacy enhancement from a compositional perspective. Samples were collected during the processing of the three types of ALRP pieces, yielding raw ALRP pieces, water-bleached Yin-FP, ginger juice-moistened Yin-FP, steamed Yin-FP, water-bleached Yang-FP, sand-fried Yang-FP, water-bleached DFP, rice swill water-bleached DFP, and roasted DFP. Aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine, aconine, mesaconine, hypaconine, salsolinol, fuziline, and higenamine in the extracts were determined by UPLC-MS/MS, and then content analysis and cluster heatmap analysis were performed on 11 sets of samples. During the processing of the three types of ALRP pieces, bleaching significantly reduced the content of 12 alkaloids; steaming, stir-frying, and roasting significantly reduced the content of diester-type alkaloids(aconitine, mesaconitine, and hypaconitine) and significantly increased the content of monoester-type alkaloids(benzoylaconine, benzoylmesaconine, and benzoylhypaconine) and aminoalcohol-type alkaloids(aconine, mesaconine, and hypaconine). During the processing of Yin-FP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. During the processing of Yin-FP, Yang-FP, and DFP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. Steamed Yin-FP showed a higher increase in content than fried Yang-FP and roasted DFP. Comprehensive analysis of content differences in toxic and therapeutic components in three ALRP pieces suggests that the distinctive processing methods in "Jianchang" faction can indeed achieve detoxification and efficacy enhancement on ALRP. This study provides references for understanding the mechanisms of action of the three processing methods.