Use of curcumin in diagnosis,prevention,and treatment of Alzheimer＇s disease

This review summarizes and describes the use of curcumin in diagnosis,prevention,and treatment of Alzheimer＇s disease.For diagnosis of Alzheimer＇s disease,amyloid-β and highly phosphorylated tau protein are the major biomarkers.Curcumin was developed as an early diagnostic probe based on its natural fluorescence and high binding affinity to amyloid-β.Because of its multi-target effects,curcumin has protective and preventive effects on many chronic diseases such as cerebrovascular disease,hypertension,and hyperlipidemia.For prevention and treatment of Alzheimer＇s disease,curcumin has been shown to effectively maintain the normal structure and function of cerebral vessels,mitochondria,and synapses,reduce risk factors for a variety of chronic diseases,and decrease the risk of Alzheimer＇s disease.The effect of curcumin on Alzheimer＇s disease involves multiple signaling pathways：anti-amyloid and metal iron chelating properties,antioxidation and anti-inflammatory activities.Indeed,there is a scientific basis for the rational application of curcumin in prevention and treatment of Alzheimer＇s disease.

5-Demethylnobiletin and its major metabolites:efficient preparation and mechanism of their anti-proliferation activity in HepG2 cells

5-Demethylnobile tin(5-DMN),a hydroxylated polymethoxyflavone(OH-PMF)identified in aged citrus peels,has demonstrated health benefiting effects in previous studies.5-DMN undergoes biotransformation in vivo,yielding 5,3’-didemethylnobiletin(5,3’-DDMN),5,4’-didemethylnobiletin(5,4’-DDMN)and5,3’,4’-tridemethylnobiletin(5,3’,4’-TDMN).However,the anti-cancer effects of 5-DMN and its in vivo metabolites against HepG2 cells remain unclear.In this study,an efficient chemical synthetic method was developed to obtain 5-DMN and its 3 metabolites,and their molecular structures were confirmed by;H NMR and LC-MS.Cytotoxicity,cell cycle arrestment,apoptosis and caspase-3 expression were investigated to evaluate the anti-liver cancer effects of these OH-PMFs on HepG2 cells.The results showed that all 4 compounds inhibited the proliferation of HepG2 cells in a concentration-dependent manner.Their anti-proliferative activity was exerted through inducing G2/M phase arrestment,cell apoptosis and promoting expression of a key apoptotic protein called cleaved caspase-3.Our results indicated that 5,3’-DDMN and5,3’,4’-TDMN showed a stronger inhibitory activity on cell proliferation than 5-DMN,followed by 5,4’-DDMN.The expression of cleaved caspase-3 was the highest in cells treated with 5,4’-DDMN,implying that the apoptosis induced by other OH-PMFs might be mediated by other apoptotic execution proteins.Our research reveals the application potential and scientific evidence for the production and functionality of OH-PMFs.

Synthesis of Chiral β-Lactams by Pd-Catalyzed Enantioselective Amidation of Methylene C(sp3)-H Bonds

A Pd(Ⅱ)-catalyzed enantioselective intramolecular amidation of both benzylic and unbiased methylene C(sp^3)-H bonds for the straightforward synthesis of chiral B-lactams from aliphatic carboxamides is reported.The combination of 2 prinylisopropyl(PIP)auxiiary with 3,3′-subtituted BINOL ligands is crucial for the enhancement of both reactivity and enantiocontrol of differentiating unbiased meth-ylene C(sp^3)-H bonds.The desired chemoselective C-N reductive elimination was achieved by employing 2-fluoro-1-iodo-4-nitrobenzene as oxidant.

Applications of metal-organic framework composites in CO_(2) capture and conversion

Reliable technologies for CO_(2) capture and conversion(C3) are of vital importance for the establishment of a sustainable society.Metal-organic framework(MOF) composites have shown their compelling potentials for C3 due to the plentiful reticular chemistry of MOF structures and the synergistic catalysis between MOFs and the functional guests.This review focuses on the syntheses and catalytic applications towards C3 of MOF composites,which is divided into three sections.The first section gives a brief introduction about synthetic strategies of MOF composites.The second section discusses the recent progress of MOF composites in C3,including CO_(2) chemical fixation,hydrogenation,photoreduction,electro reduction and photoelectro reduction.The third section summarizes the challenges and future prospects of MOF composites for C3.We hope that this review cannot only provide an inspiration for the rational design of MOF composites for C3,but also stimulate more and more research works in this emerging area.

Tea and Citrus maxima complex induces apoptosis of human liver cancer cells via PI3K/AKT/mTOR pathway in vitro

Objective:In this study,black tea and Citrus maxima(BT-CM),yellow tea and C.maxima(YT-CM),green tea and C.maxima(GT-CM)as subjects,the active ingredient content and antioxidant activity of three tea and C.maxima(T-CM)were analyzed.The effects of three T-CMs on apoptosis of liver cells in vitro and its mechanism were further explored.Methods:National standard method and HPLC were used for active ingredient analysis.MTT,cell fow cytometry and Western blot were used to analyze the effects of three T-CMs on cell proliferation,apoptosis,and its underlying molecular mechanism.Results:The content of tea polyphenols,free amino acids,ratio of polyphenols and amino acids,ester catechins,non-ester catechins and caffeine in YT-CM and GT-CM was significantly higher than that of BT-CM.The in vitro antioxidant capacity of YT-CM and GT-CM was also significantly stronger than that of BT-CM.Three T-CMs had the effects of inhibiting proliferation,arresting cell cycle and inducing apoptosis in HepG2 and Bel7402 cells,especially YT-CM and GT-CM.Western blot analysis showed three T-CMs activated PI3K/AKT/mTOR signaling pathway and regulated the expression levels of apoptosis-related proteins Bax,Bcl-2 and Caspase-3/9.YT-CM and GT-CM had better ability to change the signal pathway than BT-CM.Conclusion:In short,T-CMs,which combined different degrees of fermentation tea with C.maxima,were rich in nutrients and biologically active substances.T-CMs,especially YT-CM and GT-CM,are healthy drinks that help to prevent and treat liver cancer.