Retinoprotective Effects of Bilberry Anthocyanins via Antioxidant, Anti-Inflammatory, and Anti-Apoptotic Mechanisms in a Visible Light-Induced Retinal Degeneration Model in Pigmented Rabbits

Plant bioactive compounds alleviate photoinduced retinal damage and asthenopia: Mechanisms, synergies, and bioavailability

The retina, an important tissue of the eye, is essential in visual transmission and sustaining adequate eyesight. However, oxidative stress and inflammatory reactions can harm retinal structure and function. Recent studies have demonstrated that exposure to light can induce oxidative stress and inflammatory reactions in retinal cells, thereby facilitating the progression of retinal damage-related diseases and asthenopia. Plant bioactive compounds such as anthocyanin, curcumin, resveratrol, lutein, zeaxanthin, epigallocatechin gallate, and quercetin are effective in alleviating retinal damage and asthenopia. Their strong oxidation resistance and unique chemical structure can prevent the retina from producing reactive oxygen species and regulating eye muscle relaxation, thus alleviating retinal damage and asthenopia. Additionally, the combination of these active ingredients produces a stronger antioxidant effect. Consequently, understanding the mechanism of retinal damage caused by light and the regulation mechanism of bioactive compounds can better protect the retina and reduce asthenopia.

Nordic diet and its benefits in neurological function: a systematic review of observational and intervention studies

Introduction

Neurological disorders have been considered the major contributors to global long-term disability and lower quality of life. Lifestyle factors, such as dietary patterns, are increasingly recognized as important determinants of neurological function. Some dietary behaviors, such as Nordic diet (ND) were likely to have protective effects on brain function. However, an understanding of the effectiveness of the ND pattern to improve neurological function and brain health is not fully understood. We review the current evidence that supports the ND pattern in various aspects of neurological function and addresses both proven and less established mechanisms of action based on its food ingredients and biochemical compounds.

Methods

In this systematic review, PubMed, Web of Science, and Scopus databases were searched from inception to February 2023. Observational and intervention studies were included.

Results

Of the 627 screened studies, 5 observational studies (including three cohorts and two cross-sectional studies) and 3 intervention studies investigating the association between ND and neurological function. Observational studies investigated the association of ND with the following neurological functions: cognition, stroke, and neuropsychological function. Intervention studies investigated the effects of ND on cognition and depression.

Discussion

Despite the limited literature on ND and its association with neurological function, several aspects of ND may lead to some health benefits suggesting neuroprotective effects. The current state of knowledge attributes the possible effects of characteristic components of the ND to its antioxidant, anti-inflammatory, lipid-lowering, gut-brain-axis modulating, and ligand activities in cell signaling pathways. Based on existing evidence, the ND may be considered a recommended dietary approach for the improvement of neurological function and brain health.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD2023451117].

Attenuation of amyloid-β-induced mitochondrial dysfunction by active components of anthocyanins in HT22 neuronal cells

Alzheimer's disease (AD) is a common form of neurodegenerative disease in the elderly. Amyloid-β (Aβ)-associated neurotoxicity is an important component of the neurodegenerative change in AD. Recent studies have revealed a beneficial effect of anthocyanins in improving learning and memory in AD animal models. Using cultured HT22 mouse hippocampal neuronal cells as an in vitro model, we examined in this study the protective effect of ten pure components of anthocyanins against Aβ ₄₂-induced cytotoxicity and also investigated the mechanism of their protective effects. We found that treatment of HT22 cells with the pure components of anthocyanins dose-dependently rescued Aβ ₄₂-induced cytotoxicity, with slightly different potencies. Using petunidin as a representative compound, we found that it enhanced mitochondrial homeostasis and function in Aβ ₄₂-treated HT22 cells. Mechanistically, petunidin facilitated β-catenin nuclear translocation and enhanced the interaction between β-catenin and TCF7, which subsequently upregulated mitochondrial homeostasis-related protein Mfn2, thereby promoting restoration of mitochondrial homeostasis and function in Aβ ₄₂-treated HT22 cells. Together, these results reveal that the pure components of anthocyanins have a strong protective effect in HT22 cells against Aβ ₄₂-induced cytotoxicity by ameliorating mitochondrial homeostasis and function in a β-catenin/TCF-dependent manner.

Remnants from the Past: From an 18th Century Manuscript to 21st Century Ethnobotany in Valle Imagna (Bergamo, Italy)

BACKGROUND

This project originated from the study of an 18th century manuscript found in Valle Imagna (Bergamo, Italy) which contains 200 plant-based medicinal remedies. A first comparison with published books concerning 20th century folk medicine in the Valley led to the designing of an ethnobotanical investigation, aimed at making a thorough comparison between past and current phytotherapy knowledge in this territory.

METHODS

The field investigation was conducted through semi-structured interviews. All data collected was entered in a database and subsequently processed. A diachronic comparison between the field results, the manuscript, and a 20th century book was then performed.

RESULTS

A total of 109 interviews were conducted and the use of 103 medicinal plants, belonging to 46 families, was noted. A decrease in number of plant taxa and uses was observed over time, with only 42 taxa and 34 uses reported in the manuscript being currently known by the people of the valley. A thorough comparison with the remedies in the manuscript highlighted similar recipes for 12 species. Specifically, the use of agrimony in Valle Imagna for the treatment of deep wounds calls back to an ancient remedy against leg ulcers based on this species.

CONCLUSIONS

The preliminary results of this study allow us to outline the partial passage through time fragments of ancient plant-based remedies once used in the investigated area.

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

In this review, we aim to provide an overview of the recent findings about the treatment of neovascular retinal diseases. The use of conventional drugs and nutraceuticals endowed with antioxidant and anti-inflammatory properties that may support conventional therapies will be considered, with the final aim of achieving risk reduction (prevention) and outcome improvement (cooperation between treatments) of such sight-threatening proliferative retinopathies. For this purpose, we consider a medicinal product one that contains well-defined compound(s) with proven pharmacological and therapeutic effects, usually given for the treatment of full-blown diseases. Rarely are prescription drugs given for preventive purposes. A dietary supplement refers to a compound (often an extract or a mixture) used in the prevention or co-adjuvant treatment of a given pathology. However, it must be kept in mind that drug-supplement interactions may exist and might affect the efficacy of certain drug treatments. Moreover, the distinction between medicinal products and dietary supplements is not always straightforward. For instance, melatonin is formulated as a medicinal product for the treatment of sleep and behavioral problems; at low doses (usually below 1 mg), it is considered a nutraceutical, while at higher doses, it is sold as a psychotropic drug. Despite their lower status with respect to drugs, increasing evidence supports the notion of the beneficial effects of dietary supplements on proliferative retinopathies, a major cause of vision loss in the elderly. Therefore, we believe that, on a patient-by-patient basis, the administration of nutraceuticals, either alone or in association, could benefit many patients, delaying the progression of their disease and likely improving the efficacy of pharmaceutical drugs.

Effects of oral Mirtogenol on retinal ganglion cell apoptosis index and intraocular pressure in the Wistar glaucoma model

The purpose of this research is to determine how Mirtogenol affects intraocular pressure (IOP) and retinal ganglion cells (RGCs) of apoptosis index in Wistar glaucoma models, as well as the relationship between IOP and RGC apoptosis index. Twelve Wistar glaucoma models were divided into two groups for experimental research with a pretest-posttest and posttest-only. The treatment group got oral administration of Mirtogenol 12.3 mg twice a day for 2 weeks, whereas the control group received a placebo in the same way. Apoptotic index and IOP were evaluated both before and after the intervention. A parametric independent t-test was used to determine the difference between groups, and a parametric paired t-test was used to determine the difference within groups. The results showed that the RGC apoptosis index in treatment groups was considerably less when compared to control groups (P < 0.001). In the treatment group, the IOP is decreased compared to the control group (mean difference: -12.67 ± 3.79 vs. 0.69 ± 4.64, respectively, P = 0.002). A significant and solid correlation was found between IOP and RGC apoptosis index (R = 0.884, P < 0.001). Thus, Mirtogenol supplementation is expected to be used to prevent glaucoma progression.

Autophagy Activation Promoted by Pulses of Light and Phytochemicals Counteracting Oxidative Stress during Age-Related Macular Degeneration

The seminal role of autophagy during age-related macular degeneration (AMD) lies in the clearance of a number of reactive oxidative species that generate dysfunctional mitochondria. In fact, reactive oxygen species (ROS) in the retina generate misfolded proteins, alter lipids and sugars composition, disrupt DNA integrity, damage cell organelles and produce retinal inclusions while causing AMD. This explains why autophagy in the retinal pigment epithelium (RPE), mostly at the macular level, is essential in AMD and even in baseline conditions to provide a powerful and fast replacement of oxidized molecules and ROS-damaged mitochondria. When autophagy is impaired within RPE, the deleterious effects of ROS, which are produced in excess also during baseline conditions, are no longer counteracted, and retinal degeneration may occur. Within RPE, autophagy can be induced by various stimuli, such as light and naturally occurring phytochemicals. Light and phytochemicals, in turn, may synergize to enhance autophagy. This may explain the beneficial effects of light pulses combined with phytochemicals both in improving retinal structure and visual acuity. The ability of light to activate some phytochemicals may further extend such a synergism during retinal degeneration. In this way, photosensitive natural compounds may produce light-dependent beneficial antioxidant effects in AMD.

Protective Effects of Dipterocarpus tuberculatus in Blue Light-Induced Macular Degeneration in A2E-Laden ARPE19 Cells and Retina of Balb/c Mice

Natural products with significant antioxidant activity have been receiving attention as one of the treatment strategies to prevent age-related macular degeneration (AMD). Reactive oxygen intermediates (ROI) including oxo-N-retinylidene-N-retinylethanolamine (oxo-A2E) and singlet oxygen-induced damage, are believed to be one of the major causes of the development of AMD. To investigate the therapeutic effects of methanol extracts of Dipterocarpus tuberculatus Roxb. (MED) against blue light (BL)-caused macular degeneration, alterations in the antioxidant activity, apoptosis pathway, neovascularization, inflammatory response, and retinal degeneration were analyzed in A2E-laden ARPE19 cells and Balb/c mice after exposure of BL. Seven bioactive components, including 2α-hydroxyursolic acid, ε-viniferin, asiatic acid, bergenin, ellagic acid, gallic acid and oleanolic acid, were detected in MED. MED exhibited high DPPH and ABTS free radical scavenging activity. BL-induced increases in intracellular reactive oxygen species (ROS) production and nitric oxide (NO) concentration were suppressed by MED treatment. A significant recovery of antioxidant capacity by an increase in superoxide dismutase enzyme (SOD) activity, SOD expression levels, and nuclear factor erythroid 2-related factor 2 (NRF2) expression were detected as results of MED treatment effects. The activation of the apoptosis pathway, the expression of neovascular proteins, cyclooxygenase-2 (COX-2)-induced inducible nitric oxide synthase (iNOS) mediated pathway, inflammasome activation, and expression of inflammatory cytokines was remarkably inhibited in the MED treated group compared to the Vehicle-treated group in the AMD cell model. Furthermore, MED displayed protective effects in BL-induced retinal degeneration through improvement in the thickness of the whole retina, outer nuclear layer (ONL), inner nuclear layer (INL), and photoreceptor layer (PL) in Balb/c mice. Taken together, these results indicate that MED exhibits protective effects in BL-induced retinal degeneration and has the potential in the future to be developed as a treatment option for dry AMD with atrophy of retinal pigment epithelial (RPE) cells.

Neuroprotective effects of Vaccinium myrtillus on damage-related brain injury

Traumatic brain injury may trigger the secondary brain injury, which has the potential to be reversible and thus preventable. Anthocyanins are phylotherapeutic plants, which are reported to exhibit anti-inflammatory properties. This study aimed to evaluate the therapeutic efficiency of an anthocyanin, namely Vaccinium myrtillus, to alleviate secondary brain injury and identify possible mechanism of actions. It is hypothesized that lipid peroxidation and Na+ -K+ -ATPase activity may be involved in neuronal ischemia. Thus, brain tissue Malondialdehyde content, Na+ -K+ -ATPase content, and cleaved caspase-3 content was investigated following moderate head trauma in a rat model. Twenty-four Sprague-Dawley male rats were allocated into four groups: Control, Trauma, Solvent-Control, and Treatment. Trauma and Solvent-Control groups showed more prominent brain edema, neuronal ischemia, vascular congestion, increase in brain tissue Malondialdehyde and cleaved caspase-3 levels, and decreased Na+-K+-ATPase activity compared to the Control group. Although the Treatment group had comparable histological signs to the Trauma and Solvent-Control groups, Malondialdehyde level and Na+-K+-ATPase activity was similar to Control group, and cleaved caspase-3 levels were lower compared to Trauma and Solvent-Control groups. We conclude that anthocyanin extracts may alleviate secondary brain injury via anti-oxidative and anti-apoptotic mechanisms.

Research Progress on Absorption, Metabolism, and Biological Activities of Anthocyanins in Berries: A Review

Berries, as the best dietary sources for human health, are rich in anthocyanins, vitamins, fiber, polyphenols, essential amino acids, and other ingredients. Anthocyanins are one of the most important bioactive components in berries. The attractive color of berries is attributed to the fact that berries contain different kinds of anthocyanins. Increasing research activity has indicated that anthocyanins in berries show various biological activities, including protecting vision; antioxidant, anti-inflammatory and anti-tumor qualities; inhibition of lipid peroxidation; anti-cardiovascular disease properties; control of hypoglycemic conditions; and other activities. Hence, berries have high nutritional and medicinal values. The recognized absorption, metabolism, and biological activities of anthocyanins have promoted their research in different directions. Hence, it is necessary to systematically review the research progress and future prospects of anthocyanins to promote a better understanding of anthocyanins. The absorption, metabolism, and biological activities of anthocyanins from berries were reviewed in this paper. The findings of this study provide an important reference for basic research, product development and utilization of berries' anthocyanins in food, cosmetics, and drugs.

Microbiota mitochondria disorders as hubs for early age-related macular degeneration

Age-related macular degeneration (AMD) is a progressive neurodegenerative disease affecting the central area (macula lutea) of the retina. Research on the pathogenic mechanism of AMD showed complex cellular contribution governed by such risk factors as aging, genetic predisposition, diet, and lifestyle. Recent studies suggested that microbiota is a transducer and a modifier of risk factors for neurodegenerative diseases, and mitochondria may be one of the intracellular targets of microbial signaling molecules. This review explores studies supporting a new concept on the contribution of microbiota-mitochondria disorders to AMD. We discuss metabolic, vascular, immune, and neuronal mechanism in AMD as well as key alterations of photoreceptor cells, retinal pigment epithelium (RPE), Bruch's membrane, choriocapillaris endothelial, immune, and neuronal cells. Special attention was paid to alterations of mitochondria contact sites (MCSs), an organelle network of mitochondria, endoplasmic reticulum, lipid droplets (LDs), and peroxisomes being documented based on our own electron microscopic findings from surgically removed human eyes. Morphometry of Bruch's membrane lipids and proteoglycans has also been performed in early AMD and aged controls. Microbial metabolites (short-chain fatty acids, polyphenols, and secondary bile acids) and microbial compounds (lipopolysaccharide, peptidoglycan, and bacterial DNA)-now called postbiotics-in addition to local effects on resident microbiota and mucous membrane, regulate systemic metabolic, vascular, immune, and neuronal mechanisms in normal conditions and in various common diseases. We also discuss their antioxidant, anti-inflammatory, and metabolic effects as well as experimental and clinical observations on regulating the main processes of photoreceptor renewal, mitophagy, and autophagy in early AMD. These findings support an emerging concept that microbiota-mitochondria disorders may be a crucial pathogenic mechanism of early AMD; and similarly, to other age-related neurodegenerative diseases, new treatment approaches should be targeted at these disorders.

Cyanidin-3-O-Glucoside Regulates the M1/M2 Polarization of Microglia via PPARγ and Aβ42 Phagocytosis Through TREM2 in an Alzheimer's Disease Model

Microglial polarization plays an essential role in the progression and regression of neurodegenerative disorders. Cyanidin-3-O-glucoside (C3G), a dietary anthocyanin found in many fruits and vegetables, has been reported as an antioxidant, anti-inflammatory, and antitumor agent. However, there have been no reports on whether C3G can regulate the M1/M2 shift in an Alzheimer's disease model. We attempted to investigate the effects of C3G on M1/M2 polarization and the mechanism to regulate anti-inflammation and phagocytosis, both in vitro and in vivo. HMC3 cells were treated with β-amyloid (Aβ42) in the presence or absence of 50 μM C3G for different time intervals, and APPswe/PS1ΔE9 mice were orally administered 30 mg/kg/day of C3G for 38 weeks. The in vitro data revealed that C3G could shift the M1 phenotype of microglia to M2 by reducing the expression of M1-specific markers (CD86 and CD80), inflammatory cytokines (IL-Iβ, IL-6, TNF-α), reactive oxygen species, and enhancing the expression of M2-specific markers (CD206 and CD163). The APPswe/PS1ΔE9 mice results were consistent with the in vitro data, indicating a significant reduction in inflammatory cytokines and higher expression of M2-specific markers such as CD206 and Arg1 in C3G-treated Alzheimer's disease model mice. Additionally, C3G was found to upregulate PPARγ expression levels both in vitro and in vivo, whereas a PPARγ antagonist (GW9662) was found to block C3G-mediated effects in vitro. In this study, we confirmed that C3G could regulate microglial polarization by activating PPARγ and eliminating accumulated β-amyloid by enhancing Aβ42 phagocytosis through the upregulation of TREM2.

Inherited Retinal Dystrophies: Role of Oxidative Stress and Inflammation in Their Physiopathology and Therapeutic Implications

Inherited retinal dystrophies (IRDs) are a large group of genetically and clinically heterogeneous diseases characterized by the progressive degeneration of the retina, ultimately leading to loss of visual function. Oxidative stress and inflammation play fundamental roles in the physiopathology of these diseases. Photoreceptor cell death induces an inflammatory state in the retina. The activation of several molecular pathways triggers different cellular responses to injury, including the activation of microglia to eliminate debris and recruit inflammatory cells from circulation. Therapeutical options for IRDs are currently limited, although a small number of patients have been successfully treated by gene therapy. Many other therapeutic strategies are being pursued to mitigate the deleterious effects of IRDs associated with oxidative metabolism and/or inflammation, including inhibiting reactive oxygen species’ accumulation and inflammatory responses, and blocking autophagy. Several compounds are being tested in clinical trials, generating great expectations for their implementation. The present review discusses the main death mechanisms that occur in IRDs and the latest therapies that are under investigation.

Protective Effect of Ribes nigrum Extract against Blue Light-Induced Retinal Degeneration In Vitro and In Vivo

Although blackcurrant has several health benefits, such as antioxidant and anti-inflammatory properties, its effects on the retina remain unclear. In this study, we investigated the efficacy of black currant extract (BCE) in an in vitro and in vivo model of dry age-related macular degeneration (AMD) induced by blue light. Dry macular degeneration is characterized by the abnormal accumulation of lipofuscin (e.g., N-retinylidene-N-retinylethanolamine, A2E) in the retina. Blue light (BL) significantly decreased the viability of A2E-laden human retinal pigment epithelial cells (ARPE-19). However, BCE treatment protected ARPE-19 cells from A2E and BL. A2E, which is oxidized by blue light, generates reactive oxygen species in RPE cells. Treatment with BCE significantly decreased (80.8%) reactive oxygen species levels induced by A2E and BL in a concentration-dependent manner. BCE inhibited A2E accumulation in ARPE-19 cells and significantly downregulated the expression of genes increased by A2E and BL in ARPE-19 cells. In vivo, oral administration of BCE (25–100 mg/kg) ameliorated ocular lesions of BL-induced retinal damage in a mouse model and rescued the thickness of the whole retina, photoreceptor segment layer, outer nuclear layer, and inner nuclear layer. The decrease in the number of nuclei in the outer nuclear layer induced by BL was also rescued by BCE. Additionally, BCE administration rescued (40.0%) the BL-induced reduction in the expression level of superoxide dismutase 1. Taken together, our results suggest that BCE may have preventive and therapeutic effects on dry AMD through its antioxidant activity and inhibition of lipofuscin accumulation in the retina.

Treatment of Glaucoma with Natural Products and Their Mechanism of Action: An Update

Glaucoma is one of the leading causes of irreversible blindness. It is generally caused by increased intraocular pressure, which results in damage of the optic nerve and retinal ganglion cells, ultimately leading to visual field dysfunction. However, even with the use of intraocular pressure-lowering eye drops, the disease still progresses in some patients. In addition to mechanical and vascular dysfunctions of the eye, oxidative stress, neuroinflammation and excitotoxicity have also been implicated in the pathogenesis of glaucoma. Hence, the use of natural products with antioxidant and anti-inflammatory properties may represent an alternative approach for glaucoma treatment. The present review highlights recent preclinical and clinical studies on various natural products shown to possess neuroprotective properties for retinal ganglion cells, which thereby may be effective in the treatment of glaucoma. Intraocular pressure can be reduced by baicalein, forskolin, marijuana, ginsenoside, resveratrol and hesperidin. Alternatively, Ginkgo biloba, Lycium barbarum, Diospyros kaki, Tripterygium wilfordii, saffron, curcumin, caffeine, anthocyanin, coenzyme Q10 and vitamins B3 and D have shown neuroprotective effects on retinal ganglion cells via various mechanisms, especially antioxidant, anti-inflammatory and anti-apoptosis mechanisms. Extensive studies are still required in the future to ensure natural products' efficacy and safety to serve as an alternative therapy for glaucoma.

Discovering the Potential of Natural Antioxidants in Age-Related Macular Degeneration: A Review

Age-related macular degeneration (AMD) is a multifactorial disease associated with anatomical changes in the inner retina. Despite tremendous advances in clinical care, there is currently no cure for AMD. This review aims to evaluate the published literature on the therapeutic roles of natural antioxidants in AMD. A literature search of PubMed, Web of Science and Google Scholar for peer-reviewed articles published between 1 January 2011 and 31 October 2021 was undertaken. A total of 82 preclinical and 18 clinical studies were eligible for inclusion in this review. We identified active compounds, carotenoids, extracts and polysaccharides, flavonoids, formulations, vitamins and whole foods with potential therapeutic roles in AMD. We evaluated the integral cellular signaling pathways including the activation of antioxidant pathways and angiogenesis pathways orchestrating their mode of action. In conclusion, we examined the therapeutic roles of natural antioxidants in AMD which warrant further study for application in clinical practice. Our current understanding is that natural antioxidants have the potential to improve or halt the progression of AMD, and tailoring therapeutics to the specific disease stages may be the key to preventing irreversible vision loss.

Role of Oxidative Stress in Retinal Disease and the Early Intervention Strategies: A Review

The retina, owing to its cellular anatomy and physical location, is susceptible to generating reactive oxygen species (ROS), which are associated with several major retinal diseases. When ROS exceeds the body's natural antioxidants, the retina is in a state of oxidative stress, which is recognized as the pathogenesis of retinal diseases. The early stage of the pathogenic process is an adaptive change in which oxidative stress and endogenous defense mechanisms occur. If no treatment is applied, the retinal diseases will progress to the pathological stage with neuronal and vascular dysfunction or damage and even blindness. This review summarizes the role of oxidative stress in several common retinal diseases, including retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, glaucoma, and retinopathy of prematurity. In addition, we discuss the early intervention strategies for these diseases. An outline is provided to identify potential intervention targets for further research. Early intervention for retinal diseases is necessary and urgent and may offer hope to improve patients' quality of life through functional vision.

Protection of Aronia melanocarpa Fruit Extract from Sodium-Iodate-Induced Damages in Rat Retina

Age-related macular degeneration (AMD) is one of the major causes of blindness in elderly populations. However, the dry form of AMD has lack of effective treatments. The fruits of Aronia melanocarpa are rich in anthocyanins. In this study, the protective effects of aronia fruit extract on rat retina were investigated using a NaIO3-induced dry AMD model. Full-field electroretinograms (ERGs) showed that b-wave amplitudes were significantly decreased and the retina structures were disordered in the model. The extract treatment alleviated the injuries. The b-wave amplitudes increased 61.5% in Scotopic 0.01ERG, 122.0% in Photopic 3.0ERG, and 106.8% in Photopic 3.0 flicker; the retina structure disorder was improved with the thickness of outer nuclear layer increasing by 44.1%; and the malonaldehyde level was significantly reduced in extract-treated rat retinas compared to the model. The proteomics analysis showed the expressions of five crystallin proteins, α-crystallin A chain, β-crystallin B2, β-crystallin A3, α-crystallin B chain, and γ-crystallin S, which protect retina ganglion cells, were increased by 7.38-, 7.74-, 15.30-, 4.86-, and 9.14-fold, respectively, in the extract treatment compared to the control, which was also confirmed by immunoblotting. The results suggest that aronia fruit extract, probably due to its anthocyanins, could protect the rat retina by alleviating oxidative damages and by upregulating the crystallin proteins to protect its nerve system.

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.

Anthocyanins: Promising Natural Products with Diverse Pharmacological Activities

Anthocyanins are natural products that give color to plants. As natural plant pigments, anthocyanins also have a series of health-promoting benefits. Many researchers have proved that anthocyanins have therapeutic effects on diseases, such as circulatory, nervous, endocrine, digestive, sensory, urinary and immune systems. Additionally, a large number of studies have reported that anthocyanins have an anticancer effect through a wide range of anti-inflammatory and antioxidant effects. The anti-disease impact and mechanism of anthocyanins are diverse, so they have high research value. This review summarizes the research progress of anthocyanins on the pharmacological agents of different diseases to provide references for subsequent research.

Emerging biological therapies for the treatment of age-related macular degeneration

INTRODUCTION

Age-related macular degeneration (AMD) is the leading cause of blindness in individuals over age 50 in developed countries. Current therapy for nonexudative AMD (neAMD) is aimed at modifying risk factors and vitamin supplementation to slow progression, while intravitreal anti-vascular endothelial factor (VEGF) injections are the mainstay for treatment of choroidal neovascularization in exudative AMD (eAMD).

AREAS COVERED

Over the past decade, promising therapies have emerged that aim to improve the current standard of care for both diseases. Clinical trials for neAMD are investigating targets in the complement cascade, vitamin A metabolism, metformin, and tetracycline, whereas clinical trials for eAMD are aiming to decrease treatment burden through novel port delivery systems, increasing drug half-life, and targeting new sites of the VEGF cascade. Stem cell and gene therapy are also being evaluated for treatment of neAMD and eAMD.

EXPERT OPINION

With an aging population, the need for effective, long term, low burden treatment options for AMD will be in increasingly high demand. Current investigations aim to address the shortcomings of current treatment options with breakthrough treatment approaches. Therapeutics in the pipeline hold promise for improving the treatment of AMD, and are on track for widespread use within the next decade.

Recombinant Human erythropoietin reduces viability of MCF-7 breast cancer cells from 3D culture without caspase activation

Recombinant human erythropoietin (rHuEPO) is the erythropoiesis-stimulating hormone that is being used concurrently with chemotherapeutic drugs in the treatment of anemia of cancer. The effect of rHuEPO on cancer cells in 3-dimensional (3D) cultures is not known. The objective of the study was to determine the effect of rHuEPO on the viability of MCF-7 breast cancer cells from 2-dimensional (2D) and 3D cell cultures. The monolayer MCF-7 cells from 2D culture and MCF-7 cell from 3D culture generated by ultra-low adhesive microplate technique, were treated with 0, 0.1, 10, 100 or 200 IU/mL rHuEPO for 24, 48 or 72 h. The effects of rHuEPO on MCF-7 cell viability and proliferation were determined using the (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT), neutral red retention time (NRRT), trypan blue exclusion assay (TBE), DNA fragmentation, acridine orange/propidium iodide staining (AO/PI) assays. The MCF-7 cells for 3D culture were also subjected to caspase assays and cell cycle analysis using flow cytometry. rHuEPO appeared to have greater effect at lowering the viability of MCF-7 cells from 3D than 2D cultures. rHuEPO significantly (p < 0.05) decreased viability and down-regulated the caspase activities of 3D MCF-7 cells in dose- and time-dependent manner. The cell cycle analysis showed that rHuEPO caused MCF-7 cells to enter the subG0/G1 phase. Thus, the study suggests that rHuEPO has a cytostatic effect on the MCF-7 breast cancer cells from 3D culture.

Potential Effects of Nutraceuticals in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), the most common cause of childhood blindness, is a hypoxia-induced eye disease characterized by retinal neovascularization. In the normal retina, a well-organized vascular network provides oxygen and nutrients as energy sources to maintain a normal visual function; however, it is disrupted when pathological angiogenesis is induced in ROP patients. Under hypoxia, inadequate oxygen and energy supply lead to oxidative stress and stimulate neovasculature formation as well as affecting the function of photoreceptors. In order to meet the metabolic needs in the developing retina, protection against abnormal vascular formation is one way to manage ROP. Although current treatments provide beneficial effects in reducing the severity of ROP, these invasive therapies may also induce life-long consequences such as systemic structural and functional complications as well as neurodevelopment disruption in the developing infants. Nutritional supplements for the newborns are a novel concept for restoring energy supply by protecting the retinal vasculature and may lead to better ROP management. Nutraceuticals are provided in a non-invasive manner without the developmental side effects associated with current treatments. These nutraceuticals have been investigated through various in vitro and in vivo methods and are indicated to protect retinal vasculature. Here, we reviewed and discussed how the use of these nutraceuticals may be beneficial in ROP prevention and management.

The Anti-Neuroinflammatory Role of Anthocyanins and Their Metabolites for the Prevention and Treatment of Brain Disorders

Anthocyanins are naturally occurring polyphenols commonly found in fruits and vegetables. Numerous studies have described that anthocyanin-rich foods may play a crucial role in the prevention and treatment of different pathological conditions, which have encouraged their consumption around the world. Anthocyanins exhibit a significant neuroprotective role, mainly due to their well-recognized antioxidant and anti-inflammatory properties. Neuroinflammation is an intricate process relevant in both homeostatic and pathological circumstances. Since the progression of several neurological disorders relies on neuroinflammatory process, targeting brain inflammation has been considered a promising strategy in those conditions. Recent data have shown the anti-neuroinflammatory abilities of many anthocyanins and of their metabolites in the onset and development of several neurological disorders. In this review, it will be discussed the importance and the applicability of these polyphenolic compounds as neuroprotective agents and it will be also scrutinized the molecular mechanisms underlying the modulation of neuroinflammation by these natural compounds in the context of several brain diseases.

Using Medicinal Plants in Valmalenco (Italian Alps): From Tradition to Scientific Approaches

This ethnobotanical survey was carried out in Caspoggio (Valmalenco, SO, Italy) with the purpose of investigating the traditional uses of medicinal plants. Moreover, a bibliographic research meant to validate or refute the uses, focusing on the potentially responsible compounds, was performed. Fifty-nine species, attributable to 30 families (Asteraceae, Pinaceae, Malvaceae, and Lamiaceae the most cited), were mentioned. Arnica montana, anti-inflammatory for traumas and musculoskeletal pains; Pinus mugo, expectorant; Malva sylvestris, anti-inflammatory and soothing; Achillea moschata, digestive. The compounds, responsible for the therapeutic activities, are often polyphenols and terpenoids: helenanin in A. montana, α-pinene, δ-3-carene, and limonene in P. mugo, gossypin and malvin in M. sylvestris, luteolin and apigenin in A. moschata. Scientific evidence for at least one of the traditional activities described was found for 50 species but only in 26 out of 196 works consulted, it is possible to make a comparison between investigated extracts and traditional preparations. This study is thus a stimulus to new phytochemical investigations, mimicking as much as possible the traditional preparations. This work is part of the European Interreg Italy-Switzerland B-ICE project, aimed at creating a management model for the ongoing climate change and searching for new sources of territory valorization as attractions for tourists.

A Re-Appraisal of Pathogenic Mechanisms Bridging Wet and Dry Age-Related Macular Degeneration Leads to Reconsider a Role for Phytochemicals

Which pathogenic mechanisms underlie age-related macular degeneration (AMD)? Are they different for dry and wet variants, or do they stem from common metabolic alterations? Where shall we look for altered metabolism? Is it the inner choroid, or is it rather the choroid–retinal border? Again, since cell-clearing pathways are crucial to degrade altered proteins, which metabolic system is likely to be the most implicated, and in which cell type? Here we describe the unique clearing activity of the retinal pigment epithelium (RPE) and the relevant role of its autophagy machinery in removing altered debris, thus centering the RPE in the pathogenesis of AMD. The cell-clearing systems within the RPE may act as a kernel to regulate the redox homeostasis and the traffic of multiple proteins and organelles toward either the choroid border or the outer segments of photoreceptors. This is expected to cope with the polarity of various domains within RPE cells, with each one owning a specific metabolic activity. A defective clearance machinery may trigger unconventional solutions to avoid intracellular substrates’ accumulation through unconventional secretions. These components may be deposited between the RPE and Bruch’s membrane, thus generating the drusen, which remains the classic hallmark of AMD. These deposits may rather represent a witness of an abnormal RPE metabolism than a real pathogenic component. The empowerment of cell clearance, antioxidant, anti-inflammatory, and anti-angiogenic activity of the RPE by specific phytochemicals is here discussed.

Tea Grape Reduces Abdominal Aortic Occlusion-Induced Lung Injury

Introduction

Ischemia-associated mortality caused by aortic cross-clamps, as in ruptured abdominal aorta aneurysm surgeries, and reperfusion following their removal represent some of the main emergency conditions in cardiovascular surgery. The purpose of our study was to examine the potential protective effect of tea grape against aortic occlusion-induced lung injury using biochemical, histopathological, immunohistochemical, and quantitative analyses.

Methods

Thirty-two male Sprague-Dawley rats were randomly assigned into four groups: control (healthy), glycerol + ischemia/reperfusion (I/R) (sham), I/R, and I/R + tea grape.

Results

Following aortic occlusion, we observed apoptotic pneumocytes, thickening in the alveolar wall, edematous areas in interstitial regions, and vascular congestion. We also observed an increase in pulmonary malondialdehyde (MDA) levels and decrease in pulmonary glutathione (GSH). However, tea grape reduced apoptotic pneumocytes, edema, vascular congestion, and MDA levels, while increased GSH levels in lung tissue.

Conclusion

Our findings suggest that tea grape is effective against aortic occlusion-induced lung injury by reducing oxidative stress and apoptosis.

Analysis of Changes in Retinal Photoreceptors Using Optical Coherence Tomography in a Feline Model of Iodoacetic Acid-induced Retinal Degeneration

Purpose

We investigated structural changes in the retina by using optical coherence tomography (OCT) in a feline model of retinal degeneration using iodoacetic acid (IAA).

Methods

We examined 22 eyes of 11 felines over 2 years of age. The felines had fasted for 12 hours and were intravenously injected with IAA 20 mg/kg of body weight. OCT (Spectralis OCT) was performed at the point where the ends of the retinal vessels collected in the lateral direction from the optic nerve head and area centralis. Similarly, OCT was performed four times at 1-week intervals following injections, at which point the felines were sacrificed and histologic examinations were performed. Using OCT, the thickness of each layer of the retina was measured.

Results

The average body weight of the three male and eight female felines investigated in this study was 1.61 ± 0.19 kg. The mean total retinal thickness of the felines before injection was 221.32 ± 9.82 µm, with a significant decrease in the retinal thickness at 2, 3, and 4 weeks following injections of 186.41 ± 35.42, 174.56 ± 31.94, and 175.35 ± 33.84 µm, respectively (p = 0.028, 0.027, and 0.027, respectively). The thickness of the outer nuclear layer was 57.49 ± 8.03 µm before injection and 29.26 ± 17.87, 25.62 ± 13.88, and 31.60 ± 18.38 µm at 2, 3, and 4 weeks, respectively, after injection (p = 0.028, 0.028, 0.046, respectively).

Conclusions

In a feline model of retinal degeneration using IAA, the total retinal thickness and the thickness of the outer nuclear layer were shown to decrease significantly on OCT.

Authentication of the Bilberry Extracts by an HPLC Fingerprint Method Combining Reference Standard Extracts

A simple and fast high-performance liquid chromatography (HPLC) fingerprint method combining reference standard extract for the identification of bilberry extract was developed and validated. Six batches of bilberry extract collected from different manufactures were used to establish the HPLC fingerprint. Other berry extracts—such as blueberry extracts, mulberry extracts, cranberry extracts, and black rice extracts—were also analyzed for their HPLC chromatograms. The fingerprints of five batches of bilberry extract showed high similarities, while one batch was distinguished from others. Additionally, the content of anthocyanin Cyanidin-3-O-glucoside (Cy-3-glc) in each berry extract was analyzed and compared. The results indicate that this HPLC fingerprint method, combining reference standard extracts, could be used for the authentication and quality control of bilberry extracts.

Cyanidin-3-glucoside attenuates 4-hydroxynonenal- and visible light-induced retinal damage in vitro and in vivo

4-Hydroxynonenal (HNE) is a highly reactive end-product of lipid peroxidation reaction that leads to retinal pigment epithelial (RPE) cell damage. Cyanidin-3-glucoside (C3G), the most abundant anthocyanin in the edible parts of plants, is a nutritional supplement used for preventing retinal damage. However, the protective effect of C3G against HNE-induced RPE cell damage remains to be elucidated. The protective mechanisms of C3G on ARPE-19 cells after HNE exposure were investigated in this study. Results showed that compared with HNE-treated cells, the viability of ARPE-19 cells was significantly (P < 0.05) increased after 1 and 5 μM C3G treatment. C3G exhibited a significant (P < 0.05) inhibitory effect on the expression of senescence-associated β-galactosidase in ARPE-19 cells. VEGF levels in the C3G groups were significantly (P < 0.05) decreased relative to those of the HNE-treated group. C3G also regulated the release of two inflammatory mediators, namely monocyte chemoattractant protein 1 and interleukine-8, in ARPE-19 cells after HNE treatment. Furthermore, C3G attenuated retinal cell apoptosis in pigmented rabbits induced by visible light. Therefore, our data showed that C3G has efficient protective effects on HNE-induced apoptosis, angiogenesis, and dysregulated cytokine production in ARPE-19 cells.

Nutrients for Prevention of Macular Degeneration and Eye-Related Diseases

The risk of macular degeneration can be reduced through the consumption of antioxidant-rich foods, supplements, and nutraceutical formulas. This review focuses on the antioxidants, vitamins, and minerals that have been reported for reducing the risk of macular degeneration and other eye-related diseases. Antioxidants including anthocyanins, carotenoids, flavonoids, and vitamins have been shown to reduce the risk of eye-related diseases. Anthocyanins extracted from berries are powerful antioxidants. Cyanidin, delphinidin, malvidin, pelargonidin, peonidin, and petunidin are anthocyanin aglycones detected in berries, currants, and other colored fruits and vegetables. β-Carotene, as well as xanthophyll lutein and zeaxanthin, have been reported to reduce the risk of macular degeneration. Flavonoids from plants help in the prevention of eye-related diseases through anti-inflammatory mechanisms. A combination of these antioxidants, vitamins, and minerals possess a synergistic effect on the prevention or risk reduction of macular degeneration. Formulas have been developed as dietary supplements to cater to the high demand from consumers and patients with eye problems. Many of the formulated dietary supplements that are sold in the market have been clinically proven for their efficacy to treat eye diseases. Although the bioactivities in the supplement capsules or tablets have been scientifically established for reducing risks of several diseases, which include macular degeneration and other eye-related diseases, knowledge on the right dosage, efficacy, and bioavailability of antioxidants, vitamins, and minerals is important for consumers. The information may help them make the best decision in choosing the right dietary supplements and nutraceuticals following the evidence-based recommended dosages and reference intakes for improving general health and preventing eye-related diseases. This review covers the potential causal factors involved in eye diseases, clinically proven treatments, and controversial findings on the antioxidants in the prevention of macular degeneration. Future studies should consider multiethnic and multicenter trials for eliminating potential bias in research.

Xanthohumol Protects Morphology and Function in a Mouse Model of Retinal Degeneration

Purpose

To investigate whether treatment with xanthohumol (XN), the principal prenylated chalconoid from Humulus lupulus (hops), is protective in a mouse model of light-induced retinal degeneration (LIRD).

Methods

Mice (129S2/SvPasCrl) were intraperitoneally injected with vehicle or XN prior to toxic light exposure and every 3 days thereafter. Retinal function was assessed by electroretinograms at 1, 2, and 4 weeks following toxic light exposure. Visual acuity was tested by optokinetic tracking 1 week and 4 weeks after toxic light exposure. Retina sections were stained with hematoxylin and eosin for morphologic analysis or by TUNEL. Redox potentials were assessed in retinal tissue by measuring levels of cysteine (CYS), cystine (CYSS), glutathione (GSH), and glutathione disulfide (GSSG) using HPLC with fluorescence detection.

Results

Toxic light significantly suppressed retinal function and visual acuity, severely disrupted the photoreceptor cell layer, and significantly decreased the number of nuclei and increased the accumulation of TUNEL-labeled cells in the outer nuclear layer. These effects were prevented by XN treatment. Treatment with XN also maintained GSSG and CYSS redox potentials and the total CYS pool in retinas of mice undergoing toxic light exposure.

Conclusions

XN treatment partially preserved visual acuity and retinal function in the LIRD mouse. Preservation of retinal CYS and of GSSG and CYSS redox potentials may indicate that XN treatment induces an increased antioxidant response, but further experiments are needed to verify this potential mechanism. To our knowledge, this is the first study to report protective effects of XN in a model of retinal degeneration.

Antioxidant and Anti-Inflammatory Effects of Blueberry Anthocyanins on High Glucose-Induced Human Retinal Capillary Endothelial Cells

Blueberries possess abundant anthocyanins, which benefit eye health. The purpose of this study was to explore the protective functional role of blueberry anthocyanin extract (BAE) and its predominant constituents, malvidin (Mv), malvidin-3-glucoside (Mv-3-glc), and malvidin-3-galactoside (Mv-3-gal), on high glucose- (HG-) induced injury in human retinal capillary endothelial cells (HRCECs). The results showed that BAE, Mv, Mv-3-glc, and Mv-3-gal enhanced cell viability (P < 0.05 versus the HG group at 24 h); decreased the reactive oxygen species (ROS, P < 0.01 versus the HG group both at 24 and 48 h); and increased the enzyme activity of catalase (CAT) and superoxide dismutase (SOD) (P < 0.05 versus the HG group both at 24 and 48 h). Mv could greatly inhibit HG-induced Nox4 expression both at 24 and 48 h (P < 0.05), while BAE and Mv-3-gal downregulated Nox4 only at 48 h (P < 0.05). Mv, Mv-3-glc, and Mv-3-gal also changed nitric oxide (NO) levels (P < 0.05). BAE and Mv-3-glc also influenced angiogenesis by decreasing the vascular endothelial cell growth factor (VEGF) level and inhibiting Akt pathway (P < 0.05). Moreover, Mv and Mv-3-glc inhibited HG-induced intercellular adhesion molecule-1 (ICAM-1, P < 0.001) and nuclear factor-kappa B (NF-κB) (P < 0.05). It indicated that blueberry anthocyanins protected HRCECs via antioxidant and anti-inflammatory mechanisms, which could be promising molecules for the development of nutraceuticals to prevent diabetic retinopathy.

Autophagy activated by SIRT6 regulates Aβ induced inflammatory response in RPEs

Age-associated dysfunction of retinal pigment epithelial cells (RPEs) is considered to be the initial trigger of retinal diseases such as age-related macular degeneration. Although autophagy is upregulated in RPEs during the course of aging, little is known about how autophagy is regulated and its functional role in RPEs. In this study, we found that expression of Sirtuin 6 (SIRT6) and autophagic markers are upregulated in RPEs of aged mice where subretinal deposition of amyloid-β is accumulated and in amyloid-β stimulated RPEs. In addition, gain and loss-of-function studies confirmed the positive role of SIRT6 in regulating autophagy. Interesting, inhibition of autophagy attenuates amyloid-β stimulated inflammatory response in RPEs. Collectively, our findings uncover the autophagy modulated by SIRT6 may be a proinflammatory mechanism for amyloid-β induced RPE dysfunction.

Dietary supplementation with omega-3 polyunsaturated fatty acid-rich oils protects against visible-light-induced retinal damage in vivo

Dietary ω-3 PUFA-rich oils protect against visible-light-induced retinal damage.

Anticancer effects of Bilberry anthocyanins compared with NutraNanoSphere encapsulated Bilberry anthocyanins

Rapidly accumulating laboratory and clinical research evidence indicates that anthocyanins exhibit anticancer activity and the evaluation of bilberry anthocyanins as chemo-preventive agents is progressing. It has previously been demonstrated that anthocyanins upregulate tumor suppressor genes, induce apoptosis in cancer cells, repair and protect genomic DNA integrity, which is important in reducing age-associated oxidative stress, and improve neuronal and cognitive brain function. Bilberry anthocyanins have pronounced health effects, even though they have a low bioavailability. To increase the bioavailability, Bilberry was encapsulated in 5.5 nm diameter liposomal micelles, called NutraNanoSpheres (NNS), at a concentration of 2.5 mg/50 µl [25% (w/w) anthocyanins]. These Bilberry NNS were used to study the apoptotic/cytotoxic effects on K562 Human Erythroleukemic cancer cells. Flow cytometric fluorescent quantification of the uptake of propidium iodide in a special cell viability formulation into dead K562 cells was used to determine the effects of Bilberry on the viability of K562 cells. The concentrations of Bilberry that demonstrated the greatest levels of percentage inhibition, relative to the control populations, were biphasic, revealing a 60-70% inhibition between 0.018-1.14 mg/ml (n=6) and 60% inhibition at 4 mg/ml. The lowest percentage inhibition (30%) occurred at 2 mg/ml. The lethal dose 50 was determined to be 0.01-0.04 mg/ml of Bilberry per 105 K562 cells at 72 h of cell culture exposure. At 48 h incubation, the highest percentage of inhibition was only 27%, suggesting involvement of a long-term apoptotic event. These levels, which demonstrated direct cytotoxic effects, were 8-40 times lower than levels required for Bilberry that is not encapsulated. The increase in bioavailability with the Bilberry NNS and its water solubility demonstrated the feasibility of using Bilberry NNS in cancer patient clinical trials.

Effects of Sanguis Draconis on Perforator Flap Survival in Rats

Sanguis draconis, a resin known to improve blood circulation, relieve pain, stimulate tissue regeneration, and heal wounds, is widely used in clinical practice. In this study, we prepared an ethanol extract of sanguis draconis (EESD) containing 75.08 mg/g of dracorhodin. The experiment was carried out on 20 rats that were divided into two groups, a control group (n = 10) and an EESD group (n = 10). All the rats underwent a perforator flap surgery, after which post-operative abdominal compressions of EESD were given to the EESD group for seven days, while the control group received saline. Flap survival percentages were determined after seven days, and were found to be significantly higher in the EESD group than in the control group. Results of laser Doppler flowmetry (LDF) showed that perforator flaps in the EESD group had higher perfusion values than those of the control group. The flap tissues were stained with hematoxylin and eosin, followed by immunohistochemical evaluation. Superoxide dismutase (SOD) expression and micro-vessel development markedly increased in the EESD group, while malondialdehyde (MDA) levels decreased. This is the first study to investigate the effect of sanguis draconis on perforator flap survival. Our results demonstrate that sanguis draconis can improve perforator flap survival in rats by promoting microvessel regeneration and blood perfusion.

Protective Effect of Proanthocyanidins from Sea Buckthorn (Hippophae Rhamnoides L.) Seed against Visible Light-Induced Retinal Degeneration in Vivo

Dietary proanthocyanidins (PACs) as health-protective agents have become an important area of human nutrition research because of their potent bioactivities. We investigated the retinoprotective effects of PACs from sea buckthorn (Hippophae rhamnoides L.) seed against visible light-induced retinal degeneration in vivo. Pigmented rabbits were orally administered sea buckthorn seed PACs (50 and 100 mg/kg/day) for 14 consecutive days of pre-illumination and seven consecutive days of post-illumination. Retinal function was quantified via electroretinography 7 days after light exposure. Retinal damage was evaluated by measuring the thickness of the full-thickness retina and outer nuclear layer 7 days after light exposure. Sea buckthorn seed PACs significantly attenuated the destruction of electroretinograms and maintained the retinal structure. Increased retinal photooxidative damage was expressed by the depletion of glutathione peroxidase and catalase activities, the decrease of total antioxidant capacity level and the increase of malondialdehyde level. Light exposure induced a significant increase of inflammatory cytokines (IL-1β, TNF-α and IL-6) and angiogenesis (VEGF) levels in retina. Light exposure upregulated the expression of pro-apoptotic proteins Bax and caspase-3 and downregulated the expression of anti-apoptotic protein Bcl-2. However, sea buckthorn seed PACs ameliorated these changes induced by light exposure. Sea buckthorn seed PACs mediated the protective effect against light-induced retinal degeneration via antioxidant, anti-inflammatory and antiapoptotic mechanisms.

Protective Effect of Total Flavones from Hippophae rhamnoides L. against Visible Light-Induced Retinal Degeneration in Pigmented Rabbits

Sea buckthorn (Hippophae rhamnoides L.) flavones have been used as candidate functional food ingredients because of their bioactivities, such as treating cardiovascular disorders, lowering plasma cholesterol level, and regulating immune function. However, the protective effects of sea buckthorn flavones against retinal degeneration remain unclear to date. This study investigated the protective effects of total flavones from H. rhamnoides (TFH) against visible light-induced retinal damage and explored the related mechanisms in pigmented rabbits. Rabbits were treated with TFH (250 and 500 mg/kg) for 2 weeks pre-illumination and 1 week post-illumination until sacrifice. Retinal function was quantified by performing electroretinography 1 day before and 1, 3, and 7 days after light exposure (18000 lx for 2 h). Retinal degeneration was evaluated by measuring the thickness of the outer nuclear layer (ONL) and performing the TUNEL assay 7 days after light exposure. Enzyme-linked immunosorbent assay, Western blot analysis, and immunohistochemistry were used to explore the antioxidant, anti-inflammatory, and anti-apoptotic mechanisms of TFH during visible light-induced retinal degeneration. Light exposure produced a degenerative effect primarily on the ONL, inner nuclear layer (INL), and ganglion cell layer (GCL). TFH significantly attenuated the destruction of electroretinograms caused by light damage, maintained ONL thickness, and decreased the number of TUNEL-positive cells in the INL and GCL. TFH ameliorated the retinal oxidative stress (GSH-Px, CAT, T-AOC, and MDA), inflammation (IL-1β and IL-6), angiogenesis (VEGF), and apoptosis (Bax, Bcl2, and caspase-3) induced by light exposure. Therefore, TFH exhibited protective effects against light-induced retinal degeneration by increasing the antioxidant defense mechanisms, suppressing pro-inflammatory and angiogenic cytokines, and inhibiting retinal cell apoptosis.