Screening of Anti-Lipase Components of Artemisia argyi Leaves Based on Spectrum-Effect Relationships and HPLC-MS/MS

Abstract

Pancreatic lipase is a key lipase for triacylglyceride digestion and absorption, which is recognized as a promising target for treatment of metabolic disorders. Natural phytochemicals are hopeful sources for pancreatic lipase inhibitors. The leaves of Artemisia argyi H.Lév. and Vaniot (AL) is commonly used as herbal medicine or food supplement in China and other Asian countries for hundreds of years. AL mainly contains essential oils, phenolic acids, flavonoids and terpenoids, which exhibit many pharmacological activities such as antioxidant, anti-inflammatory, antimicrobial, analgetic, anti-cancer, anti-diabetes and immunomodulatory effects. However, the anti-lipase activity of AL was lack of study and the investigation of anti-lipase ingredients from AL was also insufficient. In the present study, the anti-lipase activity of AL was evaluated in vitro and the potentially pancreatic lipase inhibitors of AL were investigated. High performance liquid chromatography was used to establish fingerprints of AL samples, and fifteen peaks were selected. The anti-lipase activities of AL samples were evaluated by a pancreatic lipase inhibition assay. Then, the spectrum-effect relationships between fingerprints and pancreatic lipase inhibitory activities were investigated to identify the anti-lipase constitutes in AL. As the results, four caffeoylquinic acids, which were identified as neochlorogenic acid, chlorogenic acid, isochlorogenic acid B, and isochlorogenic acid A by high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry, were selected as potential pancreatic lipase inhibitors in AL. Moreover, anti-lipase activity assessment and molecular docking study of the four compounds were performed to validate the potential lipase inhibitors in AL. The results revealed that the four caffeoylquinic acids in AL as bioactive compounds displayed with anti-lipase activity. The present research provided evidences for the anti-lipase activity of AL, and suggested that some bioactive compounds in AL could be used as lead compounds for discovering of new pancreatic lipase inhibitors.

Keywords: Artemisia argyi leaves; HPLC-MS/MS; anti-lipase activity; pancreatic lipase; spectrum-effect relationships.

FIGURE 1

HPLC fingerprints (A) and reference fingerprint (B) of twenty-two batches (S1-S22) of Artemisia argyi leaves.

FIGURE 2

Heatmap analysis of fifteen common peaks (P1-P15) areas and anti-lipase activities (IC₅₀ values of pancreatic lipase) of twenty-two batches (S1-S22) of Artemisia argyi leaves. Red represents higher contents and blue indicates lower contents.s

FIGURE 3

Heatmap analysis of Pearson correlation of fifteen common peaks (P1-P15) areas and anti-lipase activities (IC₅₀ values of pancreatic lipase). Red represents positive correlated and green indicates negative correlated.

FIGURE 4

The results of spectrum-effect relationships by PLSR model. (A) PLSR linear regression; (B) Regression coefficients between fifteen common peaks and anti-lipase activities (IC₅₀ values of pancreatic lipase); (C) VIP values of fifteen common peaks.

FIGURE 5

The typical total ion chromatogram of AL sample in negative ion mode. P1, neochlorogenic acid; P2, quinic acid; P3, chlorogenic acid; P4, cryptochlorogenic acid; P5, caffeic acid; P6, 5-feruoyl quinic acid; P7, isochlorogenic acid B; P8, isochlorogenic acid A; P9, isochlorogenic acid C; P10, 3,4,5-tri-O-caffeoylquinic acid; P11, hispidulin; P12, centaureidin; P13, jaceosidin; P14, eupatilin; P15, casticin.

FIGURE 6

The inhibitory effects of neochlorogenic acid, chlorogenic acid, isochlorogenic acid B and isochlorogenic acid A on pancreatic lipase.

FIGURE 7

Molecular docking analysis of four anti-lipase compounds with pancreatic lipase. (A) Preferred docking position of neochlorogenic acid on pancreatic lipase, (a) Interaction of neochlorogenic acid and amino acid residues in pancreatic lipase; (B) Preferred docking position of chlorogenic acid on pancreatic lipase, (b) Interaction of chlorogenic acid and amino acid residues in pancreatic lipase; (C) Preferred docking position of isochlorogenic acid B on pancreatic lipase, (c) Interaction of isochlorogenic acid B and amino acid residues in pancreatic lipase; (D) Preferred docking position of isochlorogenic acid A on pancreatic lipase, (d) Interaction of isochlorogenic acid A and amino acid residues in pancreatic lipase.