Exploiting autophagy-targeting natural compounds for potential antimicrobial actions.

Natural products are biologically active compounds used for therapeutic interventions for various diseases, particularly infections. Autophagy is an intracellular catabolic pathway involving lysosomal degradation and is closely associated with immunological pathways, effectively combating bacterial, viral, fungal, and parasitic infections. Accumulating evidence suggests that autophagy activation or inhibition by natural products promotes antimicrobial responses against various pathogens. Numerous natural products can modulate autophagy through diverse signaling pathways, suggesting their potential as a host-directed therapeutic strategy that may complement conventional drug regimens or help mitigate drug resistance in various infectious diseases. However, it remains largely unclear whether these effects are mediated by direct modulation of autophagy or indirectly through associated mechanisms, including enhanced immune defense, attenuation of pathological inflammation, or crosstalk with other organelle functions. Additionally, multiple pathogens can evade host responses; thus, autophagy activation may inadvertently create favorable conditions for certain pathogens. This review discusses the current knowledge of natural products in terms of their antimicrobial actions through autophagy regulation, particularly the roles of distinct natural product classes, such as polyphenols, alkaloids, terpenoids, quinones, peptides, and macrolides in modulating autophagy for potentially contributing to control various infectious diseases. Exploring the intricate molecular interplay between natural products and autophagy in limiting infections may provide valuable insights that could inform the development of innovative host-directed antimicrobial treatments based on autophagy regulation.