Goji Berry (2011, '14, '16) Supports Pigmented & Photoreceptor Cells
Learn more about diabetic retinopathy.
Goji berries, traditionally used in China for more than 2000 years, appear to have a wide variety of health benefits. While a great deal of preliminary research has been accomplished, researchers are now looking to a more detailed analysis of its potential benefit in the area of vision therapy.
Researchers wanted to investigate the impact of treatment with goji berry extract on photoreceptor cells which are implicated in the development of diabetic retinopathy. The study involved photoreceptor tissue that was exposed to chemical damage (MNU) that would normally kill or damage the photoreceptor cells. This is known as cell apoptosis - or cell death.
The scientists fed lab animals with a water solution of lycium barbarum polysaccarides, and extract from goji berry. Polysaccarides are carbohydrates consisting of sugar molecules bonded together. The condition of photoreceptor cells was examined 24 hours and again at 7 days after injection of MNU.
They found that the outer layer of photoreceptor cells, closest to the front of the eye was well protected. Along with other biochemical level analysis they concluded that the polysaccarides from goji did, in fact, have a protective role.p>Researchers: Y. Zhu, Q. Zhao, et al,
Published: Lycium barbarum polysaccharides attenuates N-methy-N-nitrosourea-induced photoreceptor cell apoptosis in rats through regulation of poly (ADP-ribose) polymerase and caspase expression, Journal of Ethnopharmacology, September, 2016
Damage due to a weakened blood/retina barrier is related to the development of diabetic retinopathy.
This study investigated the changes in the blood/retinal barrier under conditions of chronic hyperglycemia with goji extract supplementation.
The researchers noted that human retinal pigment cells (which protect the retina from damage) offer weak protection to the blood/retina barrier in the presence of glucose. Treatment with an extract of goji reversed this weakness and increased the protective effect.
The researcher noted that this is a possible prevention approach for diabetic retinopathy.
Researchers: B. Pavan, A. Capuzzo, et al,
Published: High glucose-induced barrier impairment of human retinal pigment epithelium is ameliorated by treatment with Goji berry extracts through modulation of cAMP levels, Experimental Eye Research, March, 2014.
A study investigated the broad range of potential benefits of goji berries. One result is that they lower blood sugar levels and increase insulin sensitivity. This is accomplished by improving glucose metabolism, increasing insulin production, and supporting beta cell growth in the pancreas. These results make goji of interest for treatment of diabetic retinopathy.
Researchers: J. Cheng, Z.W. Zhou, et al,
Published: An evidence-based update on the pharmacological activities and possible molecular targets of Lycium barbarum polysaccharides, Drug Design, Development and Theory, December, 2014
A specific receptor encoded by a specific gene is involved in the development of diabetic retinopathy. It is called the peroxisome proliferator activated receptor-gamma (PPAR-y) and it is encoded by the PPARG gene.
Diabetic retinopathy occurs when the retinal pigment cells in the eye are damaged; but the amino acid taurine, which is abundant in goji berries seems to be of benefit to people with the condition.
Researchers wanted to know why - the mechanism - of the process of taurine being beneficial for diabetic retinopathy patients. They investigated the action of a goji berry extract on a specific type of retinal cell (retinal ARPE-19 cell line) and identified the receptor which links to taurine and which is potentially responsible for taurine's protection against diabetic retinopathy.
In animal models the researchers were able to verify that cells that could be damaged by inflammation due to high glucose contact were protected by taurine in the goji berries.
They concluded that the taurine content of goji is at least partially responsible for its protective effect.
Researchers: M.K. Song, N.K. Salam, et al,
Published: Lycium barbarum (Goji Berry) extracts and its taurine component inhibit PPAR-_-dependent gene transcription in human retinal pigment epithelial cells: Possible implications for diabetic retinopathy treatment, Biochemical Pharmocolory, November, 2011.