It is safe to say that no one wants to get glaucoma. This is the leading cause of blindness in persons age 60 and over. Thankfully research is taking place to learn more about the disease and possible treatment targets. Two projects in particular are studying how stress causes the disease and the genetic mutations that leads to childhood glaucoma.
Stress Accelerates Aging of the Eye
Research done at the University California, Irvine suggests that aging, particularly stress induced aging, can lead to retinal ganglion cell death. Scientists found that stress, such as elevated intraocular pressure in the eye, causes retinal tissue to undergo changes from altered gene expression to changes similar to natural aging. In fact, repetitive stress accelerates the effects of aging in young retinal tissue.
The intraocular pressure has a circadian rhythm and it swings back and forth at a regular speed and it is highest for two thirds of people during the night time. While long-term intraocular pressure fluctuations have been reported to be a strong predictor of disease progression, a single intraocular pressure measurement isn’t enough to learn about glaucoma progression in patients. This study points to the cumulative impact of intraocular pressure as being responsible for the aging of the tissue.
This research shows that moderate intraocular pressure leads to retinal ganglion cell loss. Scientists want to understand the mechanism of accumulative changes in aging so as to find therapeutic targets. While early diagnosis and prevention are important, this study also shows the importance of age-specific management of glaucoma.
Childhood Glaucoma
Speaking of age-specifics, children can get glaucoma and experience vision loss. A team of researchers at Harvard Medical School discovered that a genetic mutation may be the cause of severe cases of pediatric glaucoma.
While pediatric glaucoma is rare, it is responsible for 5 percent of the cases of childhood blindness globally. Children with glaucoma require surgeries as early as the first three months of life, not to mention more surgeries throughout their childhood.
Scientists found, by way of advanced genome-sequencing technology, a mutation in the thrombospondin-1 gene in three ethnically and geographically diverse families with histories of pediatric glaucoma. These findings were confirmed in a mouse model that had this mutation and developed glaucoma.
Thrombospondin-1 is known as an inhibitor of blood vessel growth. Researchers found that the mutation in the thrombospondin-1 gene caused abnormal thrombospondin proteins to accumulate in the drainage structures of the eye that are responsible for regulating intraocular pressure. This leads to a buildup of pressure that damages the optic nerve, which leads to the loss of retinal ganglion cells, causing vision loss. These findings could lead to improved screening for pediatric glaucoma, as well as earlier and targeted treatments to prevent vision loss in children with glaucoma.
Once again research increases our understanding of the eye and this information can lead to treatments that lead to better outcomes for persons with glaucoma.
Sources:
https://www.mayoclinic.org/diseases-conditions/glaucoma/symptoms-causes/syc-20372839
https://www.som.uci.edu/news_releases/stress_accelerates_aging_of_the_eye.asp
https://hms.harvard.edu/news/new-genetic-mutation-behind-childhood-glaucoma-identified