Algae-Derived Anti-Inflammatory Compounds against Particulate Matters-Induced Respiratory Diseases: A Systematic Review

Abstract

Air pollution has recently become a subject of increasing concern in many parts of the world. The World Health Organization (WHO) estimated that nearly 4.2 million early deaths are due to exposure to fine particles in polluted air, which causes multiple respiratory diseases. Algae, as a natural product, can be an alternative treatment due to potential biofunctional properties and advantages. This systematic review aims to summarize and evaluate the evidence of metabolites derived from algae as potential anti-inflammatory agents against respiratory disorders induced by atmospheric particulate matter (PM). Databases such as Scopus, Web of Science, and PubMed were systematically searched for relevant published full articles from 2016 to 2020. The main key search terms were limited to "algae", "anti-inflammation", and "air pollutant". The search activity resulted in the retrieval of a total of 36 publications. Nine publications are eligible for inclusion in this systematic review. A total of four brown algae (Ecklonia cava, Ishige okamurae, Sargassum binderi and Sargassum horneri) with phytosterol, polysaccharides and polyphenols were reported in the nine studies. The review sheds light on the pathways of particulate matter travelling into respiratory systems and causing inflammation, and on the mechanisms of actions of algae in inhibiting inflammation. Limitations and future directions are also discussed. More research is needed to investigate the potential of algae as anti-inflammatory agents against PM in in vivo and in vitro experimental models, as well as clinically.

Keywords: algae; anti-inflammation; particulate matter; respiratory diseases.

Figure 1

Flowchart of the selection of studies.

Figure 2

Pathways of particulate matter depositing into the respiratory system through inhalation, resulting in systemic lung inflammation, lung cancer, asthma, and COPD.

Figure 3

Chemical structures of metabolites derived from algae with anti-inflammatory effects against air pollutants. (a) Fucosterol, (b) Alginic acid, (c) Dieckol, (d) Eckol, (e) Diphlorethohydroxycarmalol, (f) Gallic acid, (g) Mojabanchromanol.

Figure 3

Chemical structures of metabolites derived from algae with anti-inflammatory effects against air pollutants. (a) Fucosterol, (b) Alginic acid, (c) Dieckol, (d) Eckol, (e) Diphlorethohydroxycarmalol, (f) Gallic acid, (g) Mojabanchromanol.

Figure 4

A scheme highlighting the particulate matter-stimulated inflammatory mechanisms, as well as indicating the underlying mechanisms of protective actions of algae-derived metabolites.