# Exploring the Aerial Parts of Tetracera madagascariensis as Potential Health-Promoting Ingredient in Herbal Beverages: Phytochemical Insights, Pharmacological Evidence, and Multitarget Effects

## TL;DR

This study explores Tetracera madagascariensis as a potential herbal ingredient with antioxidant, anti-inflammatory, and bronchodilating effects, supporting its traditional use in treating asthma.

## Contribution

The study provides new evidence on the multitarget pharmacological effects and phytochemical profile of Tetracera madagascariensis.

## Key findings

- METM showed strong antioxidant activity with SC50 = 7.52 µg/mL and FRAP = 228.00 mmol FIE/kg DW.
- EFTM demonstrated bronchorelaxant activity with EC50 = 128.88 µg/mL, partially mediated through β2-adrenergic pathways.
- METM exhibited dose-dependent anti-inflammatory and analgesic effects without toxicity in mice.

## Abstract

The main objective of this study is to assess the potential antioxidant property, anti-inflammatory activity, and broncho-dilatating effect of Tetracera madagascariensis, a species traditionally used in the treatment of asthma. Qualitative and quantitative analyses on phytochemical composition and biological properties were performed to evaluate its potential as a bioactive ingredient in plant-based food applications and health-promoting beverages. DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (Ferric Reducing Antioxidant Power) models were used for antioxidant capacity. The bronchorelaxant activity of METM and its fractions was evaluated on an in vitro experimental model using isolated guinea pig trachea (n = 5) pre-contacted with histamine, while the action mechanism of EFTM was determined by using specific contracting reagents and antagonists. The analgesic and anti-inflammatory activities were evaluated in murine models (n = 5), specifically using an acetic acid-induced nociception assay and paw inflammatory oedema induced by carrageenan, respectively. Potential toxicity of the extract was evaluated in mice (n = 6). Organic acids and phenolics, particularly quinic acid and quercetin, have been detected as the main compounds. METM showed antioxidant activity (SC50 = 7.52 ± 0.26 µg/mL and FRAP = 228.00 ± 18.68 mmol FIE/kg DW). METM exerted a concentration-dependent bronchorelaxant activity (EC50 = 562.85 ± 38.00 µg/mL) as well as EFTM (EC50 = 128.88 ± 27.9 µg/mL), the most active fraction, partially mediated through β2-adrenergic pathways with additional non-competitive mechanisms. METM demonstrated dose-dependent anti-inflammatory and analgesic effects, with no toxicity in mice. These findings may support the traditional uses of T. madagascariensis as a bioactive ingredient in herbal beverages and highlight its potential as a source of phytochemicals to be used as health-promoting agents against inflammatory and respiratory disorders.