Searching for “Modifiable Risk Factors” for Glaucoma
In glaucoma treatment, the only risk factor that can be altered currently is intraocular pressure (IOP). Research is underway to explore how everyday influences like diet, air pollution, physical activities, medications, and sleep may affect an individual’s glaucoma risk. These possibilities were discussed by glaucoma specialists at the 2021 World Glaucoma Congress and shared by the World Glaucoma Association (WGA) Education Committee. Presenter Dr. Louis Pasquale, from the Icahn School of Medicine at Mount Sinai, and his colleagues found that among those with a strong genetic predisposition to elevated IOP, higher caffeine consumption correlated with higher IOP and glaucoma incidence. In addition, in pre-clinical data, Vitamin B3 (Niacinamide) acted as a “protective agent for glaucoma.” He advocated for the use of dietary supplements to complement treatment. Dr. Paul Foster, from the United Kingdom (UK), spoke about his studies regarding the relationship between glaucoma and air pollution, explaining how pollution contributes to respiratory, cardiovascular, and other diseases, “causing inflammation and oxidative stress.” For those who are genetically predisposed to oxidative stress, exposure to high levels of black carbon would likely result in high IOP. Professor Pradeep Ramulu, from Johns Hopkins University, highlighted research regarding the connection between glaucoma and physical activity. For glaucoma patients, higher activity levels were associated with slower rates of visual field loss. Dr. Anthony Khawaja, from Moorfields Eye Hospital in the UK, summarized a review he co-authored on how some medications can impact glaucoma risk. For example, systemic beta blockers have decreased the possibility of glaucoma due to their effect on blood pressure. The relationship between sleep, particularly obstructive sleep apnea (OSA), and glaucoma has not been as clear. Prof. David Mackey, from the University of Western Australia, spoke about body changes associated with OSA. Although some studies have shown a connection between OSA and glaucoma, “further research is required to see the effect of Continuous Positive Airway Pressure (CPAP) on the optic nerve.” Read more of The (WGA) Global Glaucoma Network Education Committee’s highlights about The Hunt for New Modifiable Risk Factors for Glaucoma.
Progress Reported in Stem-Cell Therapy for Blindness
“What if, in people with blinding retinal disorders, one could simply introduce into the retina healthy photoreceptor cells derived in a dish from stem cells, and restore sight?” University of Pennsylvania School of Veterinary Medicine researchers are leading an effort to develop an effective way to restore photoreceptors cells that enable people with vision loss to regain sight. Collaborating researchers are from the University of Wisconsin-Madison, Children’s Hospital of Philadelphia, and the National Institutes of Health’s National Eye Institute (NEI). This type of treatment has been impeded previously by cells dying rapidly or not integrating with the retina. Published in Stem Cell Reports, the results of a new study demonstrate how these challenges can be overcome, making substantial progress toward a “cell-based therapy.” The study team introduced “precursors of human photoreceptor cells” in the retinas of dogs, using immunosuppressive drugs to enable the cells to survive in the patients’ retinas for months and begin to form connections with existing cells. Photoreceptor cells make up a layer of the retina essential to beginning the process of vision. The factory-developed cells were injected into the retinas of seven dogs with normal vision and three with a form of retinal degeneration and then tracked over time. In those with intact retinas, the introduced cells did not connect with the existing retina cells. However, for the dogs with advanced retinal degeneration, the cells “’had a better ability to start moving into the correct layer of the retina.’” The study’s next stage will test whether the therapy results in improved vision. For more information, check out the EurekAlert! on Progress toward a stem cell-based therapy for blindness.