3D printing of melatonin-loaded esophageal stents for treatment of corrosive esophagitis

Corrosive esophagitis (CE) is a severe disease caused by accidental or suicidal ingestion of corrosive chemical agents, leading to serious esophageal stenosis or fibrosis. However, the effective and safe treatment of CE is lacking. Here, a melatonin esophagus stent (MES) was prepared using the stereolithography three-dimensional (3D) printing technology with melatonin, polyethylene glycol diacrylate (PEGDA), polyethylene glycol (PEG) 400, and other additives. The MESs with the Roman columns, caduceus, Pagoda, and mace morphologies were designed and printed, respectively. Pagoda MESs exhibited good mechanical properties, retained in the esophagus for more than 24 h, and showed rapid melatonin release. MESs had high in vitro and in vivo safety. More importantly, the implanted MES was broken down into fragments in the gastrointestinal tract and then completely evacuated from the rat body. The CE rat model was established by injecting a strong alkaline solution into the esophagus. The Pagoda MES was conveniently implanted at the injury position, which remarkably alleviated the CE symptoms, reduced inflammation, and prevented esophagus stenosis and fibrosis. 3D-printed Pagoda MESs hold promise for the treatment of CE.