Metabolomic fingerprinting of Cissampelos sympodialis Eichler leaf extract and correlation with its spasmolytic activity

Abstract

Ethnopharmacological relevance: Cissampelos sympodialis Eichler (Menispermaceae) is popularly used in northeastern Brazil for the treatment of respiratory diseases such as bronchitis and asthma. Despite many pre-clinical pharmacological studies, the compounds mediating the anti-asthma activity of polar extracts of Cissampelos sympodialis leaves have not been definitively identified.

Aim of the study: Aim of the study: The aim of the study was to investigate the correlation between the bioactivity of polar extracts prepared from the leaves of C. sympodialis and the chemical composition using a ¹H-NMR-based metabolomics approach.

Material and methods: The metabolic profile of the leaf polar extract during different phenological stages of the plant was investigated using ¹H NMR spectroscopy while simultaneously screening for spasmolytic activity using guinea-pig tracheal preparations. The content of the alkaloids previously implicated in the bioactivity of Cissampelos sympodialis was determined by HPLC.

Results: PCA analysis of the ¹H NMR data discriminated the extracts from different plant phenological stages. The contents of the major alkaloids decrease (from 2 ± 0.32 μg/mL for warifteine and 1 ± 0.14 μg/mL for methylwarifteine) to undetectable levels from 90 (CsL₉₀ extract) and 120 (CsL₁₂₀) days onwards for warifteine and methylwarifteine, respectively. All six extracts relaxed the trachea pre-contracted with carbachol, but the CsF₂₁₀ extract was more potent (EC₅₀ = 74.6 ± 7.9 μg/mL) compared to both CsL₉₀ extracts and CsL₁₈₀ in the presence of functional epithelium. PLS regression analysis of ¹H-NMR spectral data demonstrated that the spasmolytic activity was better correlated with signals for flavonol derivatives.

Conclusions: Our data challenge the idea that warifteine and methylwarifteine mediate the spasmolytic activity of the polar extract of C. sympodialis leaves.

Keywords: Asthma; Bisbenzylisoquinoline alkaloids.; Cissampelos sympodialis; Metabolomics; Spasmolytic activity.