The effect of Vaccinium uliginosum on rabbit retinal structure and light-induced function damage

Vaccinium uliginosum and Vaccinium myrtillus-Two Species-One Used as a Functional Food

Vaccinium uliginosum L. (commonly known as bog bilberry) and Vaccinium myrtillus L. (commonly known as bilberry) are species of the genus Vaccinium (family Ericaceae). The red-purple-blue coloration of blueberries is attributed largely to the anthocyanins found in bilberries. Anthocyanins, known for their potent biological activity as antioxidants, have a significant involvement in the prophylaxis of cancer or other diseases, including those of metabolic origin. Bilberry is the most important economically wild berry in Northern Europe, and it is also extensively used in juice and food production. A review of the latest literature was performed to assess the composition and biological activity of V. uliginosum and V. myrtillus. Clinical studies confirm the benefits of V. uliginosum and V. myrtillus supplementation as part of a healthy diet. Because of their antioxidant, anti-inflammatory, anti-cancer, and apoptosis-reducing activity, both bog bilberries and bilberries can be used interchangeably as a dietary supplement with anti-free radical actions in the prevention of cancer diseases and cataracts, or as a component of sunscreen preparations.

OculusGraphy: Signal Analysis of the Electroretinogram in a Rabbit Model of Endophthalmitis Using Discrete and Continuous Wavelet Transforms

BACKGROUND

The electroretinogram is a clinical test used to assess the function of the photoreceptors and retinal circuits of various cells in the eye, with the recorded waveform being the result of the summated response of neural generators across the retina.

METHODS

The present investigation involved an analysis of the electroretinogram waveform in both the time and time-frequency domains through the utilization of the discrete wavelet transform and continuous wavelet transform techniques. The primary aim of this study was to monitor and evaluate the effects of treatment in a New Zealand rabbit model of endophthalmitis via electroretinogram waveform analysis and to compare these with normal human electroretinograms.

RESULTS

The wavelet scalograms were analyzed using various mother wavelets, including the Daubechies, Ricker, Wavelet Biorthogonal 3.1 (bior3.1), Morlet, Haar, and Gaussian wavelets. Distinctive variances were identified in the wavelet scalograms between rabbit and human electroretinograms. The wavelet scalograms in the rabbit model of endophthalmitis showed recovery with treatment in parallel with the time-domain features.

CONCLUSIONS

The study compared adult, child, and rabbit electroretinogram responses using DWT and CWT, finding that adult signals had higher power than child signals, and that rabbit signals showed differences in the a-wave and b-wave depending on the type of response tested, while the Haar wavelet was found to be superior in visualizing frequency components in electrophysiological signals for following the treatment of endophthalmitis and may give additional outcome measures for the management of retinal disease.

Protective Effects of Anthocyanins Extracted from Vaccinium Uliginosum on 661W Cells Against Microwave-Induced Retinal Damage

OBJECTIVE

To study the protective effect of anthocyanins extracted from Vaccinium Uliginosum (VU) on retinal 661W cells against microwave radiation induced retinal injury.

METHODS

661W cells were divided into 6 groups, including control, model [661W cells radiated by microwave (30 mW/cm², 1 h)] and VU groups [661W cells pretreated with anthocyanins extracted from VU (25, 50, 100 and 200 µg/mL, respectively) for 48 h, and radiated by microwave 30 mW/cm², 1 h]. After treatment with different interventions, the cell apoptosis index (AI) was determined using Heochst staining; contents of malonaldehyde (MDA), glutataione (GSH), and activity of superoxide dismutase (SOD) were measured. mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1(HO-1) were detected by real time quantitative polymerase chain reaction, and the expression of HO-1 protein was examined by Western blot analysis. Nucleus and cytoplasm were separated and Nrf2 protein expression was further verified by Western blot analysis.

RESULTS

There was significant difference in AI among the groups (F=322.83, P<;0.05). Compared with the control group, AI was significantly higher in the model group and was lower in 4 VU-pretreated groups (P<;0.05). Linear regression analysis showed the decline of AI was in a dose-dependent manner with VU treatment (r=0.8419, P<;0.05). The MDA and GSH contents of 661W cells in VU-treated groups were significantly lower than the model group (P<;0.05). Compared with the model group, the SOD activity in the VU-treated groups (50, 100 and 200 µg/mL) was significantly higher (all P<;0.05). The Nrf2 and HO-1 mRNA expressions were slightly increased after irradiation, and obviously increased in 100 µg/mL VU-treated group. After irradiation, the relative expressions of HO-1 and Nrf2 proteins in nucleus were slightly increased (P<;0.05), and the changes in cytoplasm were not obvious, whereas it was significantly increased in both nucleus and cytoplasm in the VU treatment groups.

CONCLUSIONS

Anthocyanins extracted from VU could reduce apoptosis, stabilize cell membrane, and alleviate oxidant injury of mouse retinal photoreceptor 661W cells. The mechanism might be through activating Nrf2/HO-1 signal pathway and inducing HO-1 transcription and translation.

The effect of Vaccinium uliginosum extract on tablet computer-induced asthenopia: randomized placebo-controlled study

Background

To investigate the alleviation effect of Vaccinium uliginosum extract (DA9301) on tablet computer-induced asthenopia.

Methods

This was a randomized, placebo-controlled, double-blind and parallel study (Trial registration number: 2013–95). A total 60 volunteers were randomized into DA9301 (n = 30) and control (n = 30) groups. The DA9301 group received DA9301 oral pill (1000 mg/day) for 4 weeks and the control group received placebo. Asthenopia was evaluated by administering a questionnaire containing 10 questions (responses were scored on a scales of 0–6; total score: 60) regarding ocular symptoms before (baseline) and 4 weeks after receiving pills (DA9301 or placebo). The participants completed the questionnaire before and after tablet computer (iPad Air, Apple Inc.) watching at each visit. The change in total asthenopia score (TAS) was calculated and compared between the groups

Results

TAS increased significantly after tablet computer watching at baseline in DA9301 group. (from 20.35 to 23.88; p = 0.031) However, after receiving DA9301 for 4 weeks, TAS remained stable after tablet computer watching. In the control group, TAS changes induced by tablet computer watching were not significant both at baseline and at 4 weeks after receiving placebo. Further analysis revealed the scores for “tired eyes” (p = 0.001), “sore/aching eyes” (p = 0.038), “irritated eyes” (p = 0.010), “watery eyes” (p = 0.005), “dry eyes” (p = 0.003), “eye strain” (p = 0.006), “blurred vision” (p = 0.034), and “visual discomfort” (p = 0.018) significantly improved in the DA9301 group.

Conclusions

We found that oral intake of DA9301 (1000 mg/day for 4 weeks) was effective in alleviating asthenopia symptoms induced by tablet computer watching.

Trial registration

The study is registered at www.clinicaltrials.gov (registration number: NCT02641470, date of registration December 30, 2015).