The antiviral and immunomodulatory activities of propolis: An update and future perspectives for respiratory diseases

Abstract

Propolis is a complex natural product that possesses antioxidant, anti‐inflammatory, immunomodulatory, antibacterial, and antiviral properties mainly attributed to the high content in flavonoids, phenolic acids, and their derivatives. The chemical composition of propolis is multifarious, as it depends on the botanical sources from which honeybees collect resins and exudates. Nevertheless, despite this variability propolis may have a general pharmacological value, and this review systematically compiles, for the first time, the existing preclinical and clinical evidence of propolis activities as an antiviral and immunomodulatory agent, focusing on the possible application in respiratory diseases. In vitro and in vivo assays have demonstrated propolis broad‐spectrum effects on viral infectivity and replication, as well as the modulatory actions on cytokine production and immune cell activation as part of both innate and adaptive immune responses. Clinical trials confirmed propolis undeniable potential as an effective therapeutic agent; however, the lack of rigorous randomized clinical trials in the context of respiratory diseases is tangible. Since propolis is available as a dietary supplement, possible use for the prevention of respiratory diseases and their deleterious inflammatory drawbacks on the respiratory tract in humans is considered and discussed. This review opens up new perspectives on the clinical investigation of neglected propolis biological properties which, now more than ever, are particularly relevant with respect to the recent outbreaks of pandemic respiratory infections.

Propolis: An update on its chemistry and pharmacological applications

“…Various propolis extracts (e.g., aqueous, ethanolic, and hydroalcholic) at controllable laboratory condition have been found to exeret substantial antiviral activity against several types of viruses such as Herpes simplex virus type 1 and 2 (HSV-1 and HSV-2), Canine distemper virus, Human rhinovirus type 2, 3 and 4 (HRV-2, HRV-3 and HRV-4), Influenza virus type A and B, Parainfluenza virus, Human immunodeficiency virus (HIV), and Adenovirus [292,293].Research findings demonstrated that aqueous and ethanol propolis extracts exhibited a strong antiviral activity against HSV-1 [294] and HSV-2 [295] on RC-37 cells by affecting viral plaque formation and viral infection cycle. On the other hand, 0.5% aqueous extract of propolis showed potent antiviral activity against HSV-1 infected rats and rabbits thorough prevention of virus absorption into the host and inhibition of an internal step(s) during the viral replication cycle [296].…”

An Insight into Anticancer Effect of Propolis and Its Constituents: A Review of Molecular Mechanisms

“…e honeybee products like honey, beeswax, bee venom, and bee pollen have been used as traditional medicine and also exhibited antimicrobial, antioxidant, anti-inflammatory, and anticancer properties in several preclinical studies in cell line and animal experiments [13][14][15][16][17]. e word "Propolis" comes from Greek that means defense for "pro" and city or community for "polis," or the beehive in other words.…”

Natural and Semi-Synthetic Flavonoid Anti-SARS-CoV-2 Agents for the Treatment of Long COVID-19 Disease and Neurodegenerative Disorders of Cognitive Decline

“…Flavonoids have been widely utilized in traditional medical practices to combat bacterial infections [17,399,400] with some approaches focusing specifically on how to combat MDR bacteria [400][401][402][403][404]. Combination therapies with antibiotics [405] and approaches examining how the antiviral and immunomodulatory properties of flavonoids can be harnessed in the treatment of respiratory diseases have also been examined [406].…”