Dihydrocatalpol

Identification of alpha-Glucosidase Inhibitors from Scutellaria edelbergii: ESI-LC-MS and Computational Approach.[Pubmed:35209111]

Molecules. 2022 Feb 16;27(4):1322.

The recent study investigated the in vitro anti-diabetic impact of the crude extract (MeOH) and subfractions ethyl acetate (EtOAc); chloroform; n-butanol; n-hexane; and aqueous fraction of S. edelbergii and processed the active EtOAc fraction for the identification of chemical constituents for the first time via ESI-LC-MS analysis through positive ionization mode (PIM) and negative ionization mode (NIM); the identified compounds were further validated through computational analysis via standard approaches. The crude extract and subfractions presented appreciable activity against the alpha-glucosidase inhibitory assay. However, the EtOAc fraction with IC(50) = 0.14 +/- 0.06 microg/mL revealed the maximum potential among the fractions used, followed by the MeOH and n-hexane extract with IC(50) = 1.47 +/- 0.14 and 2.18 +/- 0.30 microg/mL, respectively. Moreover, the acarbose showed an IC(50) = 377.26 +/- 1.20 microg/ mL whereas the least inhibition was observed for the chloroform fraction, with an IC(50) = 23.97 +/- 0.14 microg/mL. Due to the significance of the EtOAc fraction, when profiled for its chemical constituents, it presented 16 compounds among which the flavonoid class was dominant, and offered eight compounds, of which six were identified in NIM, and two compounds in PIM. Moreover, five terpenoids were identified-three and two in NIM and PIM, respectively-as well as two alkaloids, both of which were detected in PIM. The EtOAc fraction also contained one phenol that was noticed in PIM. The detected flavonoids, terpenoids, alkaloids, and phenols are well-known for their diverse biomedical applications. The potent EtOAc fraction was submitted to computational analysis for further validation of alpha-glucosidase significance to profile the responsible compounds. The pharmacokinetic estimations and protein-ligand molecular docking results with the support of molecular dynamic simulation trajectories at 100 ns suggested that two bioactive compounds-Dihydrocatalpol and leucosceptoside A-from the EtOAc fraction presented excellent drug-like properties and stable conformations; hence, these bioactive compounds could be potential inhibitors of alpha-glucosidase enzyme based on intermolecular interactions with significant residues, docking score, and binding free energy estimation. The stated findings reflect that S. edelbergii is a rich source of bioactive compounds offering potential cures for diabetes mellitus; in particular, Dihydrocatalpol and leucosceptoside A could be excellent therapeutic options for the progress of novel drugs to overcome diabetes mellitus.

[Absorption and pharmacokinetics of radix rehmanniae in rats].[Pubmed:24358782]

Yao Xue Xue Bao. 2013 Sep;48(9):1464-70.

In this paper, absorption and pharmacokinetic study of Radix Rehmanniae was studied by liquid chromatography coupled with mass spectrometry method after oral administration to rats. By comparing the chromatograms of ultraviolet, full scan, extracted ion and selective reaction monitoring (SRM) of standard solution, Radix Rehmanniae, blank plasma and rat plasma post drug administration, catalpol and ajugol were found to be the main compounds absorbed from Radix Rehmanniae. Plasma concentrations of aucubin, Dihydrocatalpol, rehmannioside A (or rehmannioside B/ melittoside) and rehmannioside D were very low. Quantitative method for catalpol and aucubin and semi-quantitative method for other compounds in rat plasma were established. The pharmacokinetic study of those absorbed components was conducted after oral administration of 6 g x kg(-1) Radix Rehmanniae water extract to rats. Cmax, t(1/2) and AUC(0-infinity) of catalpol and ajugol were (2349.05 +/- 1438.34) and (104.25 +/- 82.05) ng x mL(-1), (0.86 +/- 0.32) and (0.96 +/- 0.37) h, (4407.58 +/- 2734.89) and (226.66 +/- 188.38) ng x h x mL(-1), respectively. tmax was at 1.00 h for catalpol and ajugol. Both catalpol and ajugol were absorbed and excreted rapidly.

Two new iridoid glucosides from Picrorhiza scrophulariiflora.[Pubmed:16864432]

J Asian Nat Prod Res. 2006 Apr-May;8(3):259-63.

Two new iridoid glucosides with 3,4-Dihydrocatalpol skeleton, piscrosides A (1) and B (2) together with nine known iridoid glucosides and three known cucurbitacin glucosides, were isolated from the stems of Picrorhiza scrophulariiflora. Their structures were established by MS, 1H NMR, 13C NMR and 2D NMR methods (including HSQC, HMBC and NOESY experiments).