Bovine amniotic membrane with antioxidant and anti-inflammatory properties for the repair of alkali-burned corneas

Abstract

Corneal alkali burns are a common ocular emergency that can lead to blindness, marked by inflammation and delayed epithelial healing due to elevated oxidative stress in the intraocular environment. Mitigating the levels of reactive oxygen species (ROS) and the inflammatory response is essential for developing corneal repair materials. Amniotic membrane (AM) is frequently employed for ocular surface repair but faces limitations such as limited availability and rapid degradation. This study developed a crosslinked decellularized bovine amniotic membrane (CAM) with high transparency, enhanced mechanical strength, and enzyme resistance. By introducing Manganese-based carbon dots (Mn CDs), the composite (CDs@CAM) retained the physical properties of CAM meanwhile brought in the multi-enzyme activities of Mn CDs. Extensive characterizations demonstrated CDs@CAM high CAT-like activity, SOD-like activity and scavenging ability of hydroxyl radical and nitrogen radical. Furthermore, cellular and animal experiments demonstrated that the CDs@CAM possessed good biocompatibility, strong antioxidant capabilities, and anti-inflammatory effects, and thus significantly promoted corneal epithelial regeneration, inhibited neovascularization, and prevented scarring in alkali burn repair. This study offers a feasible strategy for artificial corneas and corneal disease treatment.

Statement of Significance

In this study, we developed a crosslinked decellularized bovine amniotic membrane (CAM) integrated with manganese-based carbon dots (Mn CDs), creating a composite material (CDs@CAM) that addressed the issue of high oxidative stress and severe inflammation in the eye caused by corneal alkali burns. Different from the conventional amniotic membrane products, CDs@CAM retains advantageous physical properties and biocompatibility of CAM while offering potent antioxidant and anti-inflammatory capabilities. We confirmed its good biocompatibility, as well as reductions in intracellular ROS levels and inflammatory responses. Importantly, in an alkali-burned cornea model, we revealed its outstanding performance in promoting corneal epithelial repair, inhibiting neovascularization, and thus preventing scarring, restoring corneal thickness and clarity to normal levels.