Study on the mechanisms and Pharmacodynamic substances of Lian-Gui-Ning-Xin-Tang on Arrhythmia Therapy based on Pharmacodynamic-Pharmacokinetic associations.

Background: The Chinese herbal compound Lian-Gui-Ning-Xin-Tang (LGNXT), composed of 9 herbs, has a significant antiarrhythmic effect. Previous studies have confirmed that preventing intracellular Ca overload and maintaining intracellular Ca homeostasis may be the important antiarrhythmic mechanisms of LGNXT. Recent studies are focused on elucidating the mechanisms and pharmacodynamic substances of LGNXT.

Purpose: 1) To investigate the antiarrhythmic mechanisms of LGNXT; 2) to explore the association of pharmacodynamics (PD) and pharmacokinetics (PK) of the potential pharmacodynamic substances in LGNXT to further verify the mechanisms of action.

Methods: First, pharmacodynamic studies were conducted to determine the effect of LGNXT in arrhythmia at the electrophysiological, molecular, and tissue levels, and the "effect-time" relationship of LGNXT was further proposed. Next, an HPLC-MS/MS method was established to identify the "dose-time" relationship of the 9 potential compounds. Combining the "effect-time" and "dose-time" curves, the active ingredients closely related to the inhibition of inflammation, oxidative stress, and energy metabolism were identified to further verify the mechanisms and pharmacodynamic substances of LGNXT.

Results: Pretreatment with LGNXT could delay the occurrence of arrhythmias and reduce their duration and severity. LGNXT exerted antiarrhythmic effects by inhibiting MDA, LPO, IL-6, and cAMP; restoring Cx43 coupling function; and upregulating SOD, Ca-ATPase, and Na-K-ATPase levels. PK-PD association showed that nobiletin, methylophiopogonanone A, trigonelline, cinnamic acid, liquiritin, dehydropolisic acid, berberine, and puerarin were the main pharmacodynamic substances responsible for inhibiting the inflammatory response in arrhythmia. Methylophiopogonanone A, dehydropalingic acid, nobiletin, trigonelline, berberine, and puerarin in LGNXT exerted antiarrhythmic effects by inhibiting oxidative stress. Dehydropalingic acid, berberine, cinnamic acid, liquiritin, puerarin, trigonelline, methylophiopogonanone A, nobiletin, and tetrahydropalmatine exerted antiarrhythmic effects by inhibiting the energy-metabolism process.

Conclusions: LGNXT had a positive intervention effect on arrhythmias, especially ventricular tachyarrhythmias, which could inhibit inflammation, oxidative stress, and energy metabolism; positively stabilize the structure, and remodify the function of myocardial cell membranes. Additionally, the PD-PK association study revealed that methylophiopogonanone A, berberine, trigonelline, liquiritin, puerarin, tetrahydropalmatine, nobiletin, dehydropachymic acid, and cinnamic acid directly targeted inflammation, oxidative stress, and energy metabolism, which could be considered the pharmacodynamic substances of LGNXT. Thus, the antiarrhythmic mechanisms of LGNXT were further elucidated.