Amphibians as a source of bioactive antioxidant peptides: Emerging insights and therapeutic potential

Oxidative stress arises from disruption of the balance between reactive oxygen species (ROS) production and detoxification and constitutes a fundamental driver of diverse pathological diseases. Skin photoaging is a well-recognized example, primarily driven by chronic ultraviolet (UV) exposure and marked by progressive structural and functional deterioration. UV-induced ROS accelerate macromolecular degradation and impair epidermal and dermal barrier integrity, highlighting the urgent need for effective antioxidant interventions. Antioxidant peptides (AOPs), whether naturally occurring or synthetically engineered, have shown considerable potential in mitigating ROS-induced cellular damage. Amphibians, which possess highly permeable skin and are continuously challenged by fluctuating environmental conditions, represent a rich source of bioactive peptides with potent antioxidant properties. In particular, AOPs isolated from amphibian skin secretions demonstrate notable efficacy in ROS scavenging and mitigation of oxidative damage, offering promising candidates for anti-photoaging therapies. This review provides an integrated overview of ROS generation and signaling, the molecular mechanisms linking oxidative stress to skin photoaging, and the emerging biomedical potential of amphibian-derived AOPs. Deeper mechanistic insight into their structure and function is expected to accelerate the development of novel peptide-based interventions for photoaging and other oxidative stress-associated dermatological disorders.