Quanghai Shen

Bio: Quanghai Shen is an academic researcher from Chungnam National University. The author has contributed to research in topics: NFAT & Transcription factor. The author has an hindex of 3, co-authored 5 publications receiving 57 citations.

Gymnasterkoreayne G, a new inhibitory polyacetylene against NFAT transcription factor from Gymnaster koraiensis.

Abstract: A new polyacetylene, gymnasterkoreayne G (1) and seven known (2--8) constituents were isolated from the leaves of Gymnaster koraiensis. Base on extensive 1D and 2D NMR spectroscopic data, the structure of the new compound was identified as erythro-8(S)-9(Z),16-heptadecadiene-4,6-diyne-2,3,8-triol. Isolated compounds were evaluated for their ability to inhibit NFAT transcription factor. While other components did not show activity, most of polyacetylene components markedly inhibit NFAT transcription factor. Of these compounds, gymnasterkoreayne B (3) was the most potent (IC(50) 1.44+/-0.59 microM). In term of the isomers, compound 1 (IC(50) 43.9+/-2.24 microM) with an erythro-configuration showed less inhibition than 2 (IC(50) 7.24+/-0.42 microM) with a threo-configuration.

Gymnastone, a new benzofuran derivative from Gymnaster koraiensis.

Abstract: A new benzofuran derivative, named gymnastone [5-hydroxy-6-acetyl-2-(2-propane-1,2,3-triol)-benzofuran (1)], was isolated from the aerial part ofGymnaster koraiensis, together with viscidone (2) by repeated column chromatography. The structures of both compounds were identified by physico-chemical and spectral analysis including COSY, HMQC, and HMBC experiments.

New Inhibitor against Nuclear Factor of Activated T Cells Transcription from Ribes fasciculatum var. chinense

Abstract: Two new compounds were isolated from the stem and twigs of Ribes fasciculatum var. chinense and their structures were identified to be threo-(7S,8R)-1-(4-hydroxyphenyl)-2-[4-(E)-propenylphenoxy]-propan-1-ol (1), and 5,4'-dihydroxy-7-methoxyflavone-3-O-[alpha-L-rhamnopyranosyl(1-->3)-O-alpha-L-rhamnopyranosyl(1-->6)-O-beta-D-glucopyranoside] (2). With nine other known components, they were tested on inhibitory activity against nuclear factor of activated T cells (NFAT) transcription factor. Compound 1 showed a potent inhibitory activity (IC50=15.6 microM), while compounds 4, 5 and 9 showed moderate inhibitory activity (IC50 22.4, 24.5 and 25.7 microM, respectively).

New Inhibitor Against Nuclear Factor of Activated T Cells Transcription from Ribes fasciculatum var. chinense.

Abstract: Two new compounds were isolated from the stem and twigs of Ribes fasciculatum var. chinense and their structures were identified to be threo-(7S,8R)-1-(4-hydroxyphenyl)-2-[4-(E)-propenylphenoxy]-propan-1-ol (1), and 5,4'-dihydroxy-7-methoxyflavone-3-O-[alpha-L-rhamnopyranosyl(1-->3)-O-alpha-L-rhamnopyranosyl(1-->6)-O-beta-D-glucopyranoside] (2). With nine other known components, they were tested on inhibitory activity against nuclear factor of activated T cells (NFAT) transcription factor. Compound 1 showed a potent inhibitory activity (IC50=15.6 microM), while compounds 4, 5 and 9 showed moderate inhibitory activity (IC50 22.4, 24.5 and 25.7 microM, respectively).

Antimicrobial Activity of Oleanolic and Ursolic Acids: An Update

Abstract: Triterpenoids are the most representative group of phytochemicals, as they comprise more than 20,000 recognized molecules. These compounds are biosynthesized in plants via squalene cyclization, a C30 hydrocarbon that is considered to be the precursor of all steroids. Due to their low hydrophilicity, triterpenes were considered to be inactive for a long period of time; however, evidence regarding their wide range of pharmacological activities is emerging, and elegant studies have highlighted these activities. Several triterpenic skeletons have been described, including some that have presented with pentacyclic features, such as oleanolic and ursolic acids. These compounds have displayed incontestable biological activity, such as antibacterial, antiviral, and antiprotozoal effects, which were not included in a single review until now. Thus, the present review investigates the potential use of these triterpenes against human pathogens, including their mechanisms of action, via in vivo studies, and the future perspectives about the use of compounds for human or even animal health are also discussed.

Novel inhibitors of the calcineurin/NFATc hub - alternatives to CsA and FK506?

Abstract: The drugs cyclosporine A (CsA) and tacrolimus (FK506) revolutionized organ transplantation. Both compounds are still widely used in the clinic as well as for basic research, even though they have dramatic side effects and modulate other pathways than calcineurin-NFATc, too. To answer the major open question - whether the adverse side effects are secondary to the actions of the drugs on the calcineurin-NFATc pathway - alternative inhibitors were developed. Ideal inhibitors should discriminate between the inhibition of (i) calcineurin and peptidyl-prolyl cis-trans isomerases (PPIases; the matchmaker proteins of CsA and FK506), (ii) calcineurin and the other Ser/Thr protein phosphatases, and (iii) NFATc and other transcription factors. In this review we summarize the current knowledge about novel inhibitors, synthesized or identified in the last decades, and focus on their mode of action, specificity, and biological effects.