Synthesis and biological evaluation of lycoctonine derivatives with cardiotonic and calcium channels inhibitory activities.

In our previous study, a screening of a variety of lycotonine-type diterpenoid alkaloids were screened for cardiotonic activity revealed that lycoctonine had moderate cardiac effect. In this study, a series of structurally diverse of lycoctonine were synthesized by modifying on B-ring, D-ring, E-ring, F-ring, N-atom or salt formation on lycoctonine skeleton. We evaluated the cardiotonic activity of the derivatives by isolated frog heart, aiming to identify some compounds with significantly enhanced cardiac effects, among which compound 27 with a N-isobutyl group emerged as the most promising cardiotonic candidate. Furthermore, the cardiotonic mechanism of compound 27 was preliminarily investigated. The result suggested that the cardiotonic effect of compound 27 is related to calcium channels. Patch clamp technique confirmed that the compound 27 had inhibitory effects on CaV1.2 and CaV3.2, with inhibition rates of 78.52 % ± 2.26 % and 79.05 % ± 1.59 % at the concentration of 50 µM, respectively. Subsequently, the protective effect of 27 on H9c2 cells injury induced by cobalt chloride was tested. In addition, compound 27 can alleviate CoCl2-induced myocardial injury by alleviating calcium overload. These findings suggest that compound 27 was a new structural derived from lycoctonine, which may serve as a new lead compound for the treatment of heart failure.

Diterpenoid alkaloids from two species of Delphinium.

Four new compounds (1-4) were isolated from the whole plants of two species of Delphinium, including two C20-diterpenoid alkaloids, umbrodines A and B (1 and 2), and a dibenzoxazepinone, umbrolide A (3) from Delphinium umbrosum Hand.-Mazz. and a C20-diterpenoid alkaloid, kingiadine (4) from Delphinium kingianum Bruhl. ex Huth. Ten known diterpenoid alkaloids were also isolated. Their structures were elucidated via HR-ESIMS, IR, and NMR data. Lycoctonine (11) and delectinine (12) exhibited appreciable cardiac activity. Furthermore, 11 and 12 showed cardioprotective effects against doxorubicin-induced toxicity in H9c2 cells, with the maximum protection rates of 61.63% and 51.18%, respectively.

Metabolite Profiling of Talatisamine in Heart Tissue After Oral Administration and Analysis of Cardiac Bioactivities.

The lateral roots of the Aconitum carmichaelii ("Fuzi") have been used for centuries as a cardiotonic in China. The diterpenoid alkaloid talatisamine (TA) is a major bioactive component of Fuzi, but the identity and bioactivities of the TA metabolites have not been examined in detail. In this study, metabolite profiling of TA was performed in rat heart by UPLC-MS following oral administration. Metabolites were identified by comparing protonated molecules, fragmentation patterns, and chromatographic behaviors with those of standard compounds. Metabolites of TA were then prepared and tested for cardiotonic activity on isolated frog hearts. The metabolite cammaconine, a C19 diterpenoid alkaloid with a hydroxyl group at C-18, exhibited substantial cardiotonic activity during frog heart perfusion. To further investigate the structure-cardiac effect relationships, a series of C19-diterpenoid alkaloids with 18-OH were prepared. Eight tested compounds (5: -12: ) demonstrated measurable cardioactivity, of which compound 5: with an N-methyl group and compound 7: with a methoxy at C-16 showed stronger effects on ventricular contraction than the other compounds. Thus, 18-OH is a critical structural feature determining cardiotonic activity, and efficacy is improved by the presence of N-methyl or methoxy at C-16. Preliminary mechanistic studies suggested that the cardiotonic effect of compound 5: is mediated by enhanced cellular calcium influx. Metabolites of TA with these structural features may be useful therapeutics to prevent heart failure.

[Construction of hidden curriculum in the academic experience inheritance of distinguished TCM veteran doctors].

To discuss the advantages and necessity of hidden curriculum construction in the academic experience inheritance of distinguished TCM veteran doctors by analyzing the characteristics of the hidden curriculum and the academic experience inheritance of distinguished TCM veteran doctors, and put forward viewpoints and pathways of promoting academic experience inheritance of distinguished TCM veteran doctors through the construction of hidden curriculum，such as optimal design of teaching environment，reasonable planning of teaching content and development of teaching information model，to effectively improve student cultivation quality and achieve the TCM talent cultivation goal which clinical diagnosis and treatment skills and clinical innovation ability are the core.