Mn3O4–Polydopamine Hybrid Hydrogel for Alleviation of Radiation-Induced Hyposalivation

Radiation-induced salivary gland injury (RISGI) is an inevitable and serious complication for patients with head and neck cancer. Reactive oxygen species (ROS) generated during radiotherapy are the primary cause. Hyposalivation is the most obvious symptom of RISGI. Currently, clinical interventions have not achieved the desired efficacy. Inspired by the radioprotective properties of Mn3O4and PDA nanozymes and the robust bioadhesive properties of PDA hydrogels, we designed a Mn3O4–polydopamine hybrid hydrogel (termed MP hydrogel) capable of alleviating radiation-induced hyposalivation. MP hydrogel effectively scavenges ROS and increases the viability of salivary gland cells under ionizing radiation (IR). As a proof of concept, we applied MP hydrogel to the submandibular glands (SMGs) of male Sprague–Dawley (SD) rats, one of the three major salivary glands of rats. We demonstrated that MP hydrogel effectively mitigated radiation-triggered hyposalivation after in situ gelation in rats.