Phytocomplexes as dual modulators of redox homeostasis and autophagy in host-directed antiviral therapy

Phytocomplexes are widely recognized as a source of multi-component therapeutic agents with synergistic potential. Some natural extracts possess potent antioxidant properties, largely mediated by phytochemicals such as polyphenols and flavonoids, which can neutralize reactive oxygen species (ROS) and modulate oxidative-stress–related signaling pathways critical for viral replication and inflammation. Concurrently, host-directed autophagy represents a finely tuned cellular defense mechanism that can be exploited to degrade viral components, although many viruses have evolved sophisticated strategies to evade or hijack this machinery for their own benefit. This review evaluates the antiviral potential of diverse phytocomplexes at the intersection of antioxidant activity and autophagy modulation. This work specifically addresses phytocomplexes and natural extracts as multi-component systems capable of simultaneously modulating autophagy and oxidative stress. By targeting conserved host factors rather than viral proteins, these dual-acting host-directed antivirals (HDAs) could offer a promising strategy to mitigate viral pathogenesis, reduce the likelihood of drug resistance, and provide broad-spectrum protection against emerging and re-emerging viral threats.