Protein from fat-derived stem cells may prevent retinal damage

Progranulin, a protein found in fat-derived stem cells, may reverse and perhaps prevent age-related, light-induced retinal damage, according to results from a study done in a mouse model by researchers from Gifu Pharmaceutical University and Gifu University, Japan.

Excessive exposure to light may lead to photoreceptor degeneration, and previous studies have suggested that long-term exposure to light may impact the incidence of age-related macular degeneration (AMD). In addition, photoreceptor loss is the primary cause of blindness in degenerative diseases including AMD and retinitis pigmentosa (RP).

"However, there are few effective therapeutic strategies for these diseases," said Hideaki Hara, PhD, RPh, and Kazuhiro Tsuruma, PhD, RPh, authors of the study. "Recent studies have demonstrated that bone marrow-derived stem cells protect against central nervous system degeneration with limited results. Just like the bone marrow stem cells, ASCs also self-renew and have the ability to change, or differentiate, as they grow. But since they come from fat, they can be obtained more easily under local anaesthesia and in large quantities."

Their research was published in the latest issue of STEM CELLS Translational Medicine, and showed that a single injection of adipose-derived stem cells (ASCs) reduced retinal damage induced by light exposure in mice, and that these ASCs in a conditioned medium inhibited the retinal damage by hydrogen peroxide and visible light both in the medium and in live mice.

Five days after receiving ASC injections, these mice were tested for photoreceptor degeneration and retinal dysfunction, and results showed that degeneration had been significantly inhibited. In addition, these researchers found that a type of protein known as progranulin, which is found in the ASCs, may play an important role in this protection against light-induced eye damage.

"Progranulin was identified as a major secreted protein of ASCs, which showed protective effects against retinal damage in culture and in animal tests using mice. As such, it may be a potential target for the treatment of degenerative diseases of the retina such as AMD and RP. The ASCs reduced photoreceptor degeneration without engraftment, which is concordant with the results of previous studies using bone marrow stem cells," said Drs Hara and Tsuruma.

For an abstract of this study, click here.