About Careers MedBlog Contact us
Medindia LOGIN REGISTER
Advertisement

Retinitis Pigmentosa Treatment Now Possible by Reprogramming Sugar Metabolism

by Dr. Trupti Shirole on November 15, 2016 at 3:05 PM
Font : A-A+

 Retinitis Pigmentosa Treatment Now Possible by Reprogramming Sugar Metabolism

Retinitis pigmentosa (RP) an inherited form of vision loss, is caused by genetic defects that lead to the breakdown and loss of rods, the photoreceptors in the retina that enable peripheral and night vision. Over time, the deterioration of rods compromises the function of cones, the color-sensing photoreceptors.

People with RP start to experience vision loss in childhood, and many are blind by the time they reach adulthood. Currently, there is no cure or effective treatment for RP, which affects about one in 4,000 people worldwide.

Advertisement


Columbia University Medical Center (CUMC) researchers have demonstrated that vision loss associated with a form of retinitis pigmentosa can be slowed dramatically by reprogramming the metabolism of photoreceptors, or light sensors, in the retina.

The study, conducted in mice, represents a novel approach to the treatment of RP, in which the therapy aims to correct downstream metabolic aberrations of the disease rather than the underlying genetic defect. The findings were published online today in the Journal of Clinical Investigation.
Advertisement

"Although gene therapy has shown promise in RP, it is complicated by the fact that defects in 67 genes have been linked to the disorder, and each genetic defect would require a different therapy," said study leader Stephen H. Tsang, the László Z. Bitó Associate Professor of Ophthalmology, Pathology and Cell Biology, and the Institute of Human Nutrition. "Our study shows that precision metabolic reprogramming can improve the survival and function of affected rods and cones in at least one type of RP. Since many, if not most, forms of the disorder have the same metabolic error, precision reprogramming could conceivably be applied to a wide range of RP patients."

Rods are among the most metabolically active cells in the body. They are particularly active during periods of darkness, when they burn glucose to release energy. In an earlier paper, Dr. Tsang and his colleagues theorized that rods deteriorate in RP, in part, because they lose the daytime's ability to use glucose to rebuild the rods' outer segment (the light-absorbing portion of the photoreceptor). "We hypothesized that diseased rods could be rescued by reprogramming sugar metabolism," said Dr. Tsang.

Dr. Tsang tested this hypothesis in mice with a mutation in the Pde6 gene that disrupts rod metabolism, leading to an RP-like disorder. The mice were treated so that their rods could not express Sirt6, a gene that inhibits sugar metabolism.

Examination of photoreceptors with electroretinography showed that the mice had significantly greater measures of rod and cone health than untreated controls. Overall, the metabolomes (all of the metabolites found in an organism) of the treated mice had accumulated the molecules needed to build the outer segment. In addition, both rods and cones survived longer in the treated mice than in the controls.

While the treatment significantly prolonged survival of the diseased rods and cones, it did not prevent their eventual death. "Our next challenge is to figure out how to extend the therapeutic effect of Sirt6 inhibition," said Dr. Tsang.

"Although the treatment that was used in the mice cannot be applied directly to humans, several known Sirt6 inhibitors could be evaluated for clinical use," according to Vinit B. Mahajan, a contributing researcher from the University of Iowa. The inhibitors include enzyme blockers called thiomyristoyl peptides, a common plant pigment known as quercetin, and vitexin, a substance derived from the English Hawthorn tree.

Dr. Tsang noted, "Further studies are needed to explore the exciting possibility that precision metabolic reprogramming may be used to treat other forms of RP and retinal degeneration."

Source: Eurekalert
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
What's New on Medindia
World AIDS Day 2022 - Equalize!
Test Your Knowledge on Sugar Intake and Oral Health
Test  Your Knowledge on Heart
View all
Recommended Reading
News Archive
Date
Category
Advertisement
News Category

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Blindness Facts Resting Metabolic Rate Sugar: Time to Look beyond Its Sweetness Tips for Healthy Fasting During Ramadhan Galactosemia Retinitis Pigmentosa 

Most Popular on Medindia

Hearing Loss Calculator Selfie Addiction Calculator Drug - Food Interactions Blood Donation - Recipients Calculate Ideal Weight for Infants Diaphragmatic Hernia Drug Interaction Checker Daily Calorie Requirements Color Blindness Calculator Accident and Trauma Care
This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use
×

Retinitis Pigmentosa Treatment Now Possible by Reprogramming Sugar Metabolism Personalised Printable Document (PDF)

Please complete this form and we'll send you a personalised information that is requested

You may use this for your own reference or forward it to your friends.

Please use the information prudently. If you are not a medical doctor please remember to consult your healthcare provider as this information is not a substitute for professional advice.

Name *

Email Address *

Country *

Areas of Interests