Unveiling hepatotoxicity distinction of coumarin-related compounds from glycosides to aglycones in Fructus Psoraleae by integrating UPLC-Q-TOF-MS and high content analysis

Ethnopharmacological relevance: Fructus Psoraleae (FP), the dried and ripe fruit of Cullen corylifolium (L.) Medik., is widely used due to its various clinical pharmacological effects, but its hepatotoxicity restricts its clinical application. So far, its hepatotoxic components and their underlying mechanism have not been systematically elucidated.

Aim of the study: This study was undertaken to reveal the hepatotoxicity distinction of coumarin-related compounds from glycosides to aglycones in FP and elucidate their potential mechanism.

Methods: Rats were administrated with the aqueous extract of Fructus Psoraleae (AEFP), in which eight coumarin-related compounds were focused. Subsequently, compounds exposed in rats' livers were detected by UPLC-Q-TOF-MS, and the identified hepatotoxic compounds were evaluated to elaborate their possible mechanism by the aid of high content analysis (HCA).

Results: Eight coumarin-related compounds were identified, among which psoralenoside (PO), isopsoralenoside (IPO), psoralen (P), and isopsoralen (IP) were the principally exposed compounds in rats' livers. Furocoumarinic acid glucoside (FAG), (E)-3-(4-(((2S, 3R, 4S, 5S, 6R)-3,4,5-trihydroxy-6-(hydroxymethyl) tetrahydro-2H-pyran-2-yl) oxy) benzofuran-5-yl) acrylic acid (isofurocoumarinic acid glucoside, IFAG), furocoumarinic acid (FA), and (E)-3-(4-hydroxybenzofuran-5-yl) acrylic acid (isofurocoumarinic acid, IFA) were also detected in low abundance. P, IP, FA, and IFA were identified as the hepatotoxic compounds, while their glycosides were almost non-hepatotoxic. The HCA's results showed that hepatotoxic compounds disrupted the balance in Reactive Oxygen Species (ROS), nuclear area, and mitochondrial membrane potential of HepG2 cells, leading to the occurrence of hepatotoxicity.

Conclusions: P, IP, FA, and IFA were identified as hepatotoxic compounds, from which P and IP were proposed as the important risk components for hepatotoxicity. The conversion from glycosides to aglycones played an essential role in FP-induced hepatotoxicity.

Coumarins; Fructus Psoraleae; Hepatotoxicity; Isopsoralen; Psoralen.