Traditional Chinese Medicine in Asthma – a Systematic Review of their Mechanism of Actions

Introduction: Asthma is a chronic respiratory condition that results in the inflammation and narrowing of airways. The lack of curative therapies for asthma has led to an increased use of traditional Chinese medicine (TCM) worldwide. This review aims to evaluate the mechanism of action (MOA) of TCM for used for treatment of asthma.

Methods: A systematic review was conducted in Medline®, Embase®, CENTRAL®, China National Knowledge Infrastructure (CNKI®) and WanFang® for TCM used for asthma, in accordance to the PRISMA checklist. Full-text, articles in English and Chinese language which evaluated the MOA of individual TCM or TCM used as part of a formula for the treatment of asthma were included. The searches were performed between January 2000 and June 2020. A mechanistic guideline for TCM use in asthma was proposed, modelled after Global Initiative for Asthma (GINA) guidelines.

Results: Of 9260 articles screened, 140 articles were included in the review. Twenty-six individual TCM and sixteen TCM formulas were identified. The most common MOA for individual TCM were multiple monoclonal effects (n=5), β adrenergic agonists (n=5), inhibition of interleukin-14 (n=3) and regulation of T helper cells (n=3). TCM formulas encompassed Three seeds Combination and Zhi Chuan Fang, For TCM formulas, the most common MOA identified included combination of β adrenergic agonistic, steroid like and/or regulation of T-helper 2 cells.

Conclusion: The summarized MOA of commonly utilized TCM in asthma from this review will aid TCM practitioners in better educating patients and optimising TCM use to maximise their efficacies and minimize their adverse effects