Middle Ear Histopathology Following Magnetic Delivery to the Cochlea of Prednisolone-loaded Iron Oxide Nanoparticles in Rats.

Delivery of therapy to the cochlea is a challenge and limits the efficacy of therapies meant to treat hearing loss, reverse tinnitus, and protect hearing from chemotherapy regimens. Magnetic injection is a technique that uses magnetic fields to inject nanoparticles from the middle ear into the cochlea, where they can then elute therapy to treat hearing disorders. To evaluate the safety of this treatment in the middle ear, 30 rats were subdivided into 6 groups and treated by single or multiple intratympanic injections of saline, prednisolone, nanoparticles, or nanoparticles loaded with prednisolone.

Paradoxical activation of endothelial nitric oxide synthase by NADPH oxidase.

Objective: Increased formation of reactive oxygen species (ROS) has been identified as a causative factor in endothelial dysfunction by reducing NO bioavailability and uncoupling endothelial nitric oxide synthase (eNOS). However, the specific contribution of ROS to endothelial function is not well understood.

Methods And Results: A major source of intracellular ROS is the NADPH oxidase (Nox) family of enzymes.