Clue Found for Treatment of Retinal Vascular Occlusive Disease Causing Blindness

A research team at UNIST, in collaboration with Seoul Asan Hospital and KAIST, has discovered a clue to developing a safe treatment for retinal vascular occlusion disease.

Blood vessels serve as pathways for transporting oxygen and nutrients within the body, and blockage of blood vessels can cause severe organ damage. In particular, retinal vascular occlusion disease is an emergency condition that can lead to sudden blindness without any warning symptoms.

Until now, commonly used treatments such as physical eye massage or antibody injections have not been effective, and surgical treatments like thrombolysis can cause side effects.

The research teams led by Professor Jaeheung Cho from the Department of Chemistry at UNIST, Professor Junyeop Lee from the Department of Ophthalmology at Seoul Asan Hospital, and Professor Muhyun Baek from KAIST conducted a joint study to find a new treatment method for retinal vascular occlusion disease.

The team successfully developed a stable “iron-nitric oxide complex” as a selective nitric oxide delivery agent, and animal model experiments using this complex confirmed that blood vessels expanded and blood flow in the occluded vessels was restored.

Nitric oxide performs various physiological functions in the body, including vasodilation, immune function regulation, and neural plasticity in the brain. In particular, the vasodilatory effect of nitric oxide relaxes the muscles inside blood vessels, facilitating smooth blood flow and lowering blood pressure.

Therefore, nitric oxide is used as a key component for the prevention and treatment of vascular diseases, but its unstable nature imposes many limitations on its use.

Although various studies have been conducted to deliver unstable nitric oxide, the presence of toxicity in compounds and the difficulty in controlling nitric oxide delivery have prevented selective restoration of blocked blood vessels from being observed.

To address this, the research team synthesized an iron-nitric oxide complex that mimics the active site of nitric oxide-binding proteins present in the body.

They also delivered nitric oxide to specific sites at desired times by irradiating the compound with light. This enabled the expansion of blood vessels at the blocked sites and effective restoration of blood flow.

The team demonstrated that spatiotemporal control of nitric oxide delivery is possible in animal models. This study is expected to play a key role in developing safe treatments for vascular occlusion diseases.

Schematic of treatment response for vascular occlusive disease through spatiotemporal nitric oxide delivery.

Professor Jaeheung Cho of the Department of Chemistry at UNIST said, “With the recent aging society, vascular occlusion diseases are rapidly increasing, making safe and effective vascular treatments even more important.”

Professor Cho added, “In this study, we stabilized nitric oxide, which plays a role in vasodilation in the body, through biomimicry to solve the difficulties in its use, and confirmed the possibility of treating acute vascular occlusion diseases by selectively delivering the required amount through external stimulation.”

Professor Junyeop Lee of the Department of Ophthalmology at Seoul Asan Hospital said, “The precise control of therapeutic effects using light after intraocular administration of the vasodilator, as demonstrated in this study, not only induces immediate reperfusion to preserve vision but also prevents potential side effects. Based on this, we hope to soon recommend fundamental treatments to patients with vascular occlusion who visit emergency rooms or clinics.”

The study involved Master’s and PhD integrated course student Jisoo Choi from Professor Jaeheung Cho’s research team at UNIST, PhD student Sujin Kim from Professor Junyeop Lee’s research team at Seoul Asan Hospital, and Master’s and PhD integrated course student Junhyung Kim from Professor Muhyun Baek’s research team at KAIST as co-first authors.

The research was supported by the Basic Research Program (Mid-career Researcher) of the Ministry of Science and ICT and the National Research Foundation of Korea, the Leading Research Center project of the Magnetic-based Life Care Research Center, and the Institute for Basic Science (IBS).

The research results were published on March 16, 2023, in Chem, a sister journal of the prestigious international journal Cell.

This content was produced with the assistance of AI translation services.