Compound Characterization and Metabolic Profile Elucidation after In Vitro Gastrointestinal and Hepatic Biotransformation of an Herniaria hirsuta Extract Using Unbiased Dynamic Metabolomic Data Analysis

Abstract

Herniaria hirsuta L. (Caryophyllaceae) is used for treatment of urinary stones and as a diuretic. Little is known about the active compounds and the mechanism of action. The phytochemical composition of H. hirsuta was comprehensively characterized using UHPLC-UV-HRMS (Ultrahigh-Performance Liquid Chromatography-Ultraviolet-High Resolution Mass Spectrometry) data. An in vitro gastrointestinal model was used to simulate biotransformation, which allowed the monitoring of the relative abundances of individual compounds over time. To analyze the longitudinal multiclass LC-MS data, XCMS, a platform that enables online metabolomics data processing and interpretation, and EDGE, a statistical method for time series data, were used to extract significant differential profiles from the raw data. An interactive Shiny app in R was used to rate the quality of the resulting features. These ratings were used to train a random forest model. The most abundant aglycone after gastrointestinal biotransformation was subjected to hepatic biotransformation using human S9 fractions. A diversity of compounds was detected, mainly saponins and flavonoids. Besides the known saponins, 15 new saponins were tentatively identified as glycosides of medicagenic acid, acetylated medicagenic acid and zanhic acid. It is suggested that metabolites of phytochemicals present in H. hirsuta, most likely saponins, are responsible for the pharmaceutical effects. It was observed that the relative abundance of saponin aglycones increased, indicating loss of sugar moieties during colonic biotransformation, with medicagenic acid as the most abundant aglycone. Hepatic biotransformation of this aglycone resulted in different metabolites formed by phase I and II reactions.

Inventory of Medicinal Plants Used Traditionally to Manage Kidney Diseases in North-Eastern Morocco: Ethnobotanical Fieldwork and Pharmacological Evidence

“…From a pharmacological point of view, the aqueous extract of the aerial part of this plant has an inhibitory effect on the crystallization of calcium oxalate in vitro at doses of 0.0625 mg/mL and 0.5% of plant extracts in physiological solution (9 g of NaCl /L) [ 96 , 97 ], and in vivo at a concentration of 50 mg/mL [ 98 ], also has an effect on cystine stones in different patients with congenital cystinuria at a dose of 20 g/L [ 101 ]. Phytochemical studies have reported and identified some components of H. hirsuta include flavonoids, coumarin, tannins and saponins [ 100 , 171 , 172 , 173 ]. The active component in the prevention of lithiasis has not yet been identified.…”

“…The active component in the prevention of lithiasis has not yet been identified. However, the literature suggests that the antilithiatic potential of H. hirsuta is attributed to saponins with a high probability [ 171 , 174 ]. Recently, a phytochemical study conducted to identify the bioactive constituents of H. hirsuta has shown that the aerial part of this plant is rich in phenolic compounds ( Figure 7 a,b) [ 171 ].…”

“…However, the literature suggests that the antilithiatic potential of H. hirsuta is attributed to saponins with a high probability [ 171 , 174 ]. Recently, a phytochemical study conducted to identify the bioactive constituents of H. hirsuta has shown that the aerial part of this plant is rich in phenolic compounds ( Figure 7 a,b) [ 171 ]. According to the literature, these compounds are well known for various pharmacological effects [ 175 , 176 , 177 , 178 , 179 ].…”

Effects of medicagenic acid metabolites, originating from biotransformation of an Herniaria hirsuta extract, on calcium oxalate crystallization in vitro

“…Even though a lot of research has been done to prove the activity of H. hirsuta against urolithiasis, little is known about the active compounds and the exact mechanism of action. Previous phytochemical research on Herniaria species revealed the presence of saponins, flavonoids and coumarins (Charrouf et al, 1996;Mbark et al, 1995;MBark et al 1996, van Dooren et al, 2016Peeters et al, 2020a). Literature suggests that the antilithiatic potential of H. hirsuta is attributed to saponins or metabolites thereof (van Dooren et al, 2016).…”

“…Monitoring of metabolite formation during in vitro gastrointestinal biotransformation studies of an extract of H. hirsuta showed an increase in formation of saponin aglycones, with medicagenic acid as the most abundant one. Medicagenic acid was further biotransformed in an in vitro hepatic model into several phase I and II metabolites (Peeters et al, 2020a;Peeters et al, 2020b). The aim of this study was to evaluate the in vitro effect of these metabolites on calcium oxalate crystallization and crystal-cell interaction.…”