Potential use of plant secondary metabolites in the treatment of allergic respiratory diseases (ARDs).

The occurrence of allergic respiratory diseases (ARDs) is increasing worldwide due to hypersensitivity to foreign allergens. Around 40% of the global population is affected by ARDs which are exacerbated by environmental pollution. Furthermore, prolonged ARDs-associated symptoms reduce quality of life and increase the risk of neurological disorders like depression, anxiety disorder, and dementia through oxidative stress-induced neuroinflammation. Recently, plant secondary metabolites (PSMs) have emerged as novel dietary therapeutics, which exhibit potent antioxidant and antiallergic capabilities in treating ARDs. These bioactive compounds, have antimicrobial, antiviral, and antiallergic properties, making them particularly useful in treating respiratory diseases. This review summarizes and discusses the mechanisms of ARDs and how PSMs could be alternative therapeutics for treating ARDs, as well as prospects.