Abstract
Lycium Barbarum Polysaccharides (LBP) are the active components of Wolfberry (a traditional Chinese medicine) which has long been used for improving visual function. This study aims to investigate localized changes of retinal function in a partial optic nerve transection (PONT) model, and effects of LBP on visual function. The multifocal electroretinograms (mfERG) were obtained from 30 eyes of 30 Sprague-Dawley rats. The rats were divided into 6 groups (five treatment groups and one control group). Starting from the first day of the experiment, the rats in the (PONT+LBP) group and the (LBP) group were dosed with LBP; rats in the (PONT+PBS (phosphate buffered saline)) group and the (PBS) group were dosed with PBS via nasogastric tube every day until euthanized. The dorsal part of the optic nerve was transected in the (PONT), (PONT+LBP) and (PONT+PBS) groups at the end of week 1 (day 7 after LBP or PBS feeding began). The mfERG was measured at three time points: week 2, week 3 and week 5. Significant reduction of P1 and PhNR amplitudes of the mfERG were observed in all retinal regions a week after PONT. Feeding with LBP prior to PONT preserved retinal function. All mfERG responses returned to the normal range in the superior retina, which corresponds to the transected dorsal region of the optic nerve, while most of the inferior retinal responses were significantly increased at week 4 after PONT. The ventral part of the retina had secondary degeneration which was not only limited to the ganglion cell layer, but is a widespread effect affecting the outer retina. LBP altered the functional reduction caused by PONT by regulating the signal from the outer retina.
Highlights
Glaucoma treatment will always be challenging as the retinal ganglion cells lost due to glaucomatous damage cannot be recovered
Retinal functional changes caused by partial optic nerve transection (PONT) and the effect of Lycium barbarum polysaccharides (LBP) in preserving visual function after primary injury and secondary degeneration have been demonstrated in this study
In the mammalian multifocal electroretinograms (mfERG), the main contribution to the firstorder response is from the outer retina, where the N1 involves responses from cone photoreceptors and OFF-bipolar cells; the leading edge of P1 is dominated by ON-bipolar cell activity. [18,19] Our study further demonstrates the retinal origins of the rat slow-stimulation mfERG by using an established pharmacological suppression method to inhibit the inner retinal contributions
Summary
Glaucoma treatment will always be challenging as the retinal ganglion cells lost due to glaucomatous damage cannot be recovered. An important treatment goal is to prevent further damage to retinal ganglion cells after diagnosis of glaucoma. Neuroprotection is a current therapeutic strategy that prevents retinal ganglion cells from undergoing glaucomatous degeneration. About 45% of patients still suffer glaucomatous degeneration 6 years after diagnosis and treatment, even when IOP has been wellcontrolled. [2] Lycium barbarum polysaccharides (LBP), the active component of Fructus Lycii, has been reported to have a neuroprotective effect in reducing cortical neuronal death in Alzheimer’s disease [3], in preventing retinal ganglion cell loss in ocular hypertension [4,5,6] and in retinal ischemia/reperfusion injury. Fructus Lycii, the dried mature fruit of Lycium Barbarum Linn, the Wolfberry, is a traditional Chinese medicine which has long been used for improving visual function. [2] Lycium barbarum polysaccharides (LBP), the active component of Fructus Lycii, has been reported to have a neuroprotective effect in reducing cortical neuronal death in Alzheimer’s disease [3], in preventing retinal ganglion cell loss in ocular hypertension [4,5,6] and in retinal ischemia/reperfusion injury. [7] This herb is believed to be a potential candidate for the prevention of neurological disorders
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
