Functional effect of Saffron supplementation and risk genotypes in early age-related macular degeneration: a preliminary report

Natural products for the treatment of age-related macular degeneration

BACKGROUND

Age-related macular degeneration (AMD) is a chronic retinal disease that significantly influences the vision of the elderly.

PURPOSE

There is no effective treatment and prevention method. The pathogenic process behind AMD is complex, including oxidative stress, inflammation, and neovascularization. It has been demonstrated that several natural products can be used to manage AMD, but systematic summaries are lacking.

STUDY DESIGN AND METHODS

PubMed, Web of Science, and ClinicalTrials.gov were searched using the keywords "Biological Products" AND "Macular Degeneration" for studies published within the last decade until May 2023 to summarize the latest findings on the prevention and treatment of age-related macular degeneration through the herbal medicines and functional foods.

RESULTS

The eligible studies were screened, and the relevant information about the therapeutic action and mechanism of natural products used to treat AMD was extracted. Our findings demonstrate that natural substances, including retinol, phenols, and other natural products, prevent the development of new blood vessels and protect the retina from oxidative stress in cells and animal models. However, they have barely been examined in clinical studies.

CONCLUSION

Natural products could be highly prospective candidate drugs used to treat AMD, and further preclinical and clinical research is required to validate it to control the disease.

The Role of Oral Supplementation for the Management of Age-Related Macular Degeneration: A Narrative Review

The majority of neurodegenerative eye disorders occur with aging and significantly impair quality of life. Age-related macular degeneration (AMD) is the third most common cause of visual impairment and blindness worldwide. One of the most important elements in the pathophysiology of neurodegenerative eye disease is certainly oxidative stress, with neuroinflammation and ocular ischemia which may also be significant factors. Antioxidants, either by food or oral supplementation, may be able to mitigate the deleterious effects of reactive oxygen species that build as a result of oxidative stress, ischemia, and inflammation. Over the past few decades, a number of research works examining the potential adjuvant impact of antioxidants in AMD have been published. In fact, there is not only more and more interest in already known molecules but also in new molecules that can help clinicians in the management of this complex multifactorial disease, such as astaxanthin and melatonin. However, while some studies showed encouraging outcomes, others were conflicting. In addition, more and more attention is also being paid to nutrition, considered a pivotal key point, especially to prevent AMD. For this reason, the purpose of this review is to analyze the main antioxidant molecules currently used as oral supplements for AMD treatment, as well as the role of diet and food intake in this ocular disease, to better understand how all these factors can improve the clinical management of AMD patients.

Medicinal Plant-derived Phytochemicals in Detoxification

The average worldwide human life expectancy is 70 years, with a significantly higher value in Western societies. Many modern diseases are not associated with premature mortality but with a decreased quality of life in aged patients and an excessive accumulation of various toxic compounds in the human body during life. Today, scientists are especially interested in finding compounds that can help increase a healthy lifespan by detoxifying the body. Phytotherapy with specific approaches is used in alternative medicine to remove toxins from the body. Worldwide, research is conducted to identify medicinal plant-derived molecules that, with few or no side effects, may protect the liver and other organs. This review provides updated information about the detoxification process, the traditional and modern use of the most effective medicinal plants, their active metabolites as detoxifying agents, and the mechanisms and pathways involved in the detoxification process. Among medicinal plants with substantial detoxifying properties, a major part belongs to the Asteraceae family (Silybum marianum, Cynara scolymus, Arctium lappa, Helichrysum species, Inula helenium, and Taraxacum officinale). The most widely used hepatoprotective phytocomponent is silymarin, a standardized extract from the Silybum marianum seeds containing a mixture of flavonolignans. Many polysaccharides, polyphenols, and terpenoids have a detoxifying effect. Overall, scientific data on medicinal plants used in phytotherapeutic practice worldwide provides an understanding and awareness of their efficacy in detoxification.

A Window to the Brain: The Retina to Monitor the Progression and Efficacy of Saffron Repron® Pre-Treatment in an LPS Model of Neuroinflammation and Memory Impairment

A mechanism shared by most neurodegenerative diseases, like Alzheimer's disease (AD) and Parkinson's disease (PD), is neuroinflammation. It has been shown to have a link between cognitive impairment and retinal function under neuroinflammatory conditions, confirming the essential role of the retina as a window to the brain. Here, we characterize a mouse model of LPS-induced neuroinflammation describing the parallel deterioration of both memory and visual function. Then, we demonstrate, using the Novel Object Recognition test (NOR) and electroretinogram (ERG) recordings, that preventive, chronic treatment with saffron Repron® is able to reduce the neuroinflammation process and prevent the impairment of both cognitive and visual function. The improvement in behavioral and visual function is confirmed by the pattern of expression of neuroinflammation-related genes and related proteins where pre-treatment with Repron® saffron presents a positive modulation compared with that obtained in animals treated with LPS alone. These results hold for retinal tissue and partially in the brain, where it appears that the onset of damage was delayed. This trend underlines the critical role of the retina as a most sensitive portion of the central nervous system to LPS-induced damage and could be used as a "sensor" for the early detection of neurodegenerative diseases such as Alzheimer's.

Polyunsaturated Lipids in the Light-Exposed and Prooxidant Retinal Environment

The retina is an oxidative stress-prone tissue due to high content of polyunsaturated lipids, exposure to visible light stimuli in the 400–480 nm range, and high oxygen availability provided by choroidal capillaries to support oxidative metabolism. Indeed, lipids’ peroxidation and their conversion into reactive species promoting inflammation have been reported and connected to retinal degenerations. Here, we review recent evidence showing how retinal polyunsaturated lipids, in addition to oxidative stress and damage, may counteract the inflammatory response triggered by blue light-activated carotenoid derivatives, enabling long-term retina operation despite its prooxidant environment. These two aspects of retinal polyunsaturated lipids require tight control over their synthesis to avoid overcoming their protective actions by an increase in lipid peroxidation due to oxidative stress. We review emerging evidence on different transcriptional control mechanisms operating in retinal cells to modulate polyunsaturated lipid synthesis over the life span, from the immature to the ageing retina. Finally, we discuss the antioxidant role of food nutrients such as xanthophylls and carotenoids that have been shown to empower retinal cells’ antioxidant responses and counteract the adverse impact of prooxidant stimuli on sight.

Therapeutic effects of herbal medicines in different types of retinopathies: A systematic review

Objective

Retinopathy is an ocular manifestation of systemic diseases such as diabetes and vascular diseases. Herbal drugs have been considered as an effective therapeutic option with minimal side effects for the treatment of retinopathy by reducing the symptoms and improving visual acuity. The purpose of this systematic review was to collect studies on the effectiveness of medicinal plants in the treatment or prevention of retinopathy.

Materials and Methods

A systematic literature search was performed in PubMed, Scopus, Google Scholar, and other databases in April 2021 using "herbal products" and "Retinopathy" with all their equivalent and similar terms. For this purpose, human clinical trials with the English language were included and articles with subject irrelevancy were excluded from further evaluation.

Results

Overall, 30 articles with 2324 patients were studied for possible effects of herbal therapy on retinopathy. From 30 included articles, different herbal products had been evaluated. Out of 30 selected articles, 11 articles were for the treatment of age-related macular degeneration (AMD), 14 articles covered patients with diabetic retinopathy, and the other five studies were for other retinal disorders. The outcomes in majority of the studies include changes in visual acuity (VA), fundus performance, best-corrected visual acuity (BCVA), central macular thickness (CMT), focal electroretinogram (fERG), supplements and adjuvant medications appeared to be more beneficial in patients with AMD and diabetic maculopathy.

Conclusion

Herbal therapy can be considered as a potential candidate in the adjuvant and complementary therapies of retinopathy. However, further studies are required to verify such efficiency.

The effects of crocetin on oxidative stress induced ARPE-19 cells by H2O2

The anti-apoptotic and antioxidant effects of crocetin was aimed to investigate on the oxidative damage model of ARPE-19 cells. The oxidative damage in ARPE cells was developed by H₂O₂ treatment at 800 μM. Different doses of crocetin (1-80 μM) were applied for 24 h, and the effects on viability were evaluated to find out the optimum drug dose. At first, three effective doses of crocetin (10, 20, 40 μM) on cell viability were selected for further analyses. The levels of superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) were determined, and the expression of pro-apoptotic Bax gene and anti-apoptotic Bcl-2 gene were evaluated. The most effective crocetin dose on cell viability was found to be 10 μM. After the H₂O₂ treatment, SOD and GSH were decreased and MDA were increased significantly (p = 0.011, 0.037, 0.018, respectively). Following the crocetin treatment at 10 μM, SOD and GSH activities were improved compared to the no drug group; and MDA level was declined remarkably (p = 0.022, 0.019, 0.029, respectively). The Bcl-2 level was significantly decreased (p < 0.01), while the Bax1 and Nrf2 expression and ROS level was increased significantly in the damage model group (p < 0.01). After the drug treatment, the Bax1 and Nrf2 expression level were decreased in all groups (p < 0.01). The increase in Bcl-2 expression was significant in crocetin 40 μM (p < 0.05) and the decrease in ROS level were significant in 20 μM and 40 μM doses of crocetin (p < 0.05). It has been shown that crocetin might be used as an antioxidant and anti-apoptotic agent on the hindering the effect of the oxidative damage. Following the development of the oxidative stress in the cells, crocetin reversed the damage signals. By the in vitro tests, it was shown that crocetin might be considered as an effective molecule to be used in the AMD treatment.

Dietary supplements in retinal diseases, glaucoma, and other ocular conditions

Environmental pollution, inadequate eating habits and unhealthy lifestyles have led to a tremendous increase in ocular diseases worldwide. Given the costly treatments that are currently available for the most common and threatening eye diseases (such as cataract, dry eye disorder, or diabetic retinopathy), curing these diseases or preventing refractive errors by taking nutraceuticals and natural compounds that are present in our daily diet is a very valuable intervention. The eyes are the most important part of our visual system and require micronutrients such as vitamins, carotenoids, trace metals, and omega-3 fatty acids in order to function properly and to protect themselves against light-induced and age-mediated degenerative disorders. The Mediterranean Diet (MedDiet) has been in the limelight since the 1980s because of the several health benefits it provides, including eye health. MedDiet is characterized by the consumption of small amounts of red meat, while emphasizing the intake of fish, eggs, nuts, legumes, citrus fruits, green vegetables, olives and their derivatives, especially olive oil, and dairy products in a proportionate manner, in order to achieve the maximum health benefits. The antioxidant, anti-inflammatory, and neuroprotective properties of these foods - both when used as an ingredient in the dietary regime or as a source of nutritional supplements - have shown promising results in the management of chronic degenerative ocular diseases, both in animal models and in human subjects. In this chapter, we will focus on the importance of MedDiet and natural compounds for the visual system and its role in slowing down age-related ocular degeneration.

Review of Evidence for the Usage of Antioxidants for Eye Aging

Oxidative stress is one of the common factors leading to age-related eye diseases in older adults. Factors such as high oxygen consumption, high concentration of polyunsaturated fatty acids, and cumulative exposure to high-energy visible light in the eyes, lead to excessive generation of reactive oxygen species, hence triggering apoptosis of ocular cells and giving rise to ophthalmic diseases. Dietary supplements such as carotenoids, anthocyanins, and vitamins have antioxidant properties which may be of benefit in retaining better vision or reversing vision impairment; thus, studies have been conducted to understand the role of dietary supplements in the treatment or prevention of ophthalmic diseases. While high concentration of carotenoids such as lutein and zeaxanthin decrease the risk of developing age-related macular disease, anthocyanins and vitamins play a role in the treatment and prevention of other ophthalmic diseases: saffron extract reduced intraocular pressure in glaucoma patients; bilberry extract prevented impairments in lenses and retina, as well as alleviate symptoms of dry eye disease; high concentration of beta-carotene may reduce the risk of developing cataract. Further studies with clinical measurements are required to investigate the effectiveness of antioxidants on visual function and ophthalmic diseases.

Saffron, Its Active Components, and Their Association with DNA and Histone Modification: A Narrative Review of Current Knowledge

Intensive screening for better and safer medications to treat diseases such as cancer and inflammatory diseases continue, and some phytochemicals have been discovered to have anti-cancer and many therapeutical activities. Among the traditionally used spices, Crocus sativus (saffron) and its principal bioactive constituents have anti-inflammatory, antioxidant, and chemopreventive properties against multiple malignancies. Early reports have shown that the epigenetic profiles of healthy and tumor cells vary significantly in the context of different epigenetic factors. Multiple components, such as carotenoids as bioactive dietary phytochemicals, can directly or indirectly regulate epigenetic factors and alter gene expression profiles. Previous reports have shown the interaction between active saffron compounds with linker histone H1. Other reports have shown that high concentrations of saffron bind to the minor groove of calf thymus DNA, resulting in specific structural changes from B- to C-form of DNA. Moreover, the interaction of crocin G-quadruplex was reported. A recent in silico study has shown that residues of SIRT1 interact with saffron bio-active compounds and might enhance SIRT1 activation. Other reports have shown that the treatment of Saffron bio-active compounds increases γH2AX, decreases HDAC1 and phosphorylated histone H3 (p-H3). However, the question that still remains to be addressed how saffron triggers various epigenetic changes? Therefore, this review discusses the literature published till 2022 regarding saffron as dietary components and its impact on epigenetic mechanisms. Novel bioactive compounds such as saffron components that lead to epigenetic alterations might be a valuable strategy as an adjuvant therapeutic drug.

Saffron and its active ingredients against human disorders: A literature review on existing clinical evidence

Saffron, the stigmas of Crocus sativus L., has been mentioned extensively in the traditional reference texts as a herbal medicine. Many clinical trials have been conducted on this valuable herbal substance and its main constituents following numerous cellular and animal assessments. In the present review, we have collected almost all of these clinical studies to clarify how much knowledge has clinically been achieved in this field so far and which scientific gaps are needed to be filled by more studies. A comprehensive literature review was conducted through a two-round search. First, we performed a general search for identifying the human disorders against which saffron was studied. Then, we searched specifically for the combination of saffron keywords and each disease name. Scientific databases including Scopus, PubMed, and Web of science were used for this search. Studies were collected through electronic databases from their inception up to August 2021. The largest number of these clinical studies represent the investigations into saffron efficacy in different neurological and mental disorders, particularly depression. This substance has clinically revealed significant protective effects against various types of depression, age-related macular degeneration, and allergic asthma. In some cases, such as sexual dysfunction, cognitive and metabolic disorder, the effects of saffron are still clinically open to dispute, or there are limited data on its positive influences. Overall, saffron and its constituents have promising effects on human disorders; however, it needs more clinical evidence or meta-analyses to be confirmed.

Crocin as a vision supplement

Crocin is a natural ingredient of saffron (Crocus sativus L.) flower that has shown potential for application as a supplement in eye health and preserving vision. Crocin has been examined for its potential to treat various eye diseases such as glaucoma, macular dystrophies, diabetic retinopathy, and age-related macular degeneration. This review briefly discusses the role of crocin in different eye diseases. The underlying pathophysiological pathways involved in the effect of crocin on ophthalmic diseases are also reviewed. Preclinical evidence shows the cytoprotective, antioxidative, anti-inflammatory, and blood-flow enhancing effects of crocin in retinal tissue. Crocin also affects the retinal pathologies by activating PI3K/Akt and inhibiting NF-κB signalling pathways. Clinical evidence suggests that crocin improves outcomes in patients with retinal degenerations, retinal dystrophies, and glaucoma. Overall, crocin can be suggested as a potential vision supplement in healthy populations and patients with eye diseases. However, more clinical studies with larger sample sizes and longer follow-up durations are needed to confirm the current evidence.

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.

Sequential PBM-Saffron Treatment in an Animal Model of Retinal Degeneration

Background and Objectives: Saffron treatment and photobiomodulation (PBM) are non-invasive therapeutic approaches able to mitigate and stabilize retinal degenerative diseases such as age-related macular degeneration (AMD). Although different, these therapies partially match their modulated pattern of genes. Recent attempts to find an additive effect by coadministration of saffron and PBM have failed. Instead, in this study, a different protocol to increase neuroprotection by providing consecutive saffron and PBM treatment administration is suggested. Materials and Methods: Albino rats, whose retinal damage was caused by light exposure (LD, light damage), were subjected to differential treatment protocols before and after LD: (1) PBM followed by saffron; and (2) single treatments of PBM. Thinning of the photoreceptor layer and neuro-inflammatory markers for gliosis and microglia were assessed via immune-histochemical techniques. Results: Results confirm that PBM and saffron alone cope with retinal neurodegenerative processes, preserving retinal thickness and gliosis and microglia invasion in a differential way. However, the synergistic effect of the combined treatment was restricted to the early neuroinflammation, even when provided sequentially. Conclusion: The broad spectra of action of both neuroprotectants require further investigation to identify other key pathways helpful in enhancing the effects of these two approaches in combination.

The therapeutic potential of Crocus sativus Linn.: A comprehensive narrative review of clinical trials

Crocus sativus Linn. (Saffron) is valued worldwide for its potential use in the management of various degenerative disorders, including cardiovascular diseases (CVDs), diabetes, cancer, metabolic syndrome (MetS), neurodegenerative diseases, immune disorders, and sexual dysfunction. Previous reports, based on clinical trials, suggest that crocetin, crocin, picrocrocin, and safranal are the main bioactive components of saffron with antioxidant, anti-inflammatory, and anti-apoptotic effects. In this comprehensive narrative review, we studied the recent clinical trials, investigating the medicinal applications of saffron and/or its components. The present results can provide important insights into the potential of saffron in preventing and treating different disorders, with a special focus on the underlying cellular and molecular mechanisms. However, further high-quality studies are needed to firmly establish the clinical efficacy of saffron in treating some degenerative diseases.

Therapeutic Potential of Natural Products in Treating Neurodegenerative Disorders and Their Future Prospects and Challenges

Natural products derived from plants, as well as their bioactive compounds, have been extensively studied in recent years for their therapeutic potential in a variety of neurodegenerative diseases (NDs), including Alzheimer's (AD), Huntington's (HD), and Parkinson's (PD) disease. These diseases are characterized by progressive dysfunction and loss of neuronal structure and function. There has been little progress in designing efficient treatments, despite impressive breakthroughs in our understanding of NDs. In the prevention and therapy of NDs, the use of natural products may provide great potential opportunities; however, many clinical issues have emerged regarding their use, primarily based on the lack of scientific support or proof of their effectiveness and patient safety. Since neurodegeneration is associated with a myriad of pathological processes, targeting multi-mechanisms of action and neuroprotection approaches that include preventing cell death and restoring the function of damaged neurons should be employed. In the treatment of NDs, including AD and PD, natural products have emerged as potential neuroprotective agents. This current review will highlight the therapeutic potential of numerous natural products and their bioactive compounds thatexert neuroprotective effects on the pathologies of NDs.

The Timecourses of Functional, Morphological, and Molecular Changes Triggered by Light Exposure in Sprague-Dawley Rat Retinas

Retinal neurodegeneration can impair visual perception at different levels, involving not only photoreceptors, which are the most metabolically active cells, but also the inner retina. Compensatory mechanisms may hide the first signs of these impairments and reduce the likelihood of receiving timely treatments. Therefore, it is essential to characterize the early critical steps in the neurodegenerative progression to design adequate therapies. This paper describes and correlates early morphological and biochemical changes in the degenerating retina with in vivo functional analysis of retinal activity and investigates the progression of neurodegenerative stages for up to 7 months. For these purposes, Sprague-Dawley rats were exposed to 1000 lux light either for different durations (12 h to 24 h) and examined seven days afterward (7d) or for a fixed duration (24 h) and monitored at various time points following the exposure (up to 210d). Flash electroretinogram (fERG) recordings were correlated with morphological and histological analyses to evaluate outer and inner retinal disruptions, gliosis, trophic factor release, and microglial activation. Twelve hours or fifteen hours of exposure to constant light led to a severe retinal dysfunction with only minor morphological changes. Therefore, early pathological signs might be hidden by compensatory mechanisms that silence retinal dysfunction, accounting for the discrepancy between photoreceptor loss and retinal functional output. The long-term analysis showed a transient functional recovery, maximum at 45 days, despite a progressive loss of photoreceptors and coincident increases in glial fibrillary acidic protein (GFAP) and basic fibroblast growth factor-2 (bFGF-2) expression. Interestingly, the progression of the disease presented different patterns in the dorsal and ventral retina. The information acquired gives us the potential to develop a specific diagnostic tool to monitor the disease's progression and treatment efficacy.

Pharmacological Effects of Saffron and its Constituents in Ocular Disorders from in vitro Studies to Clinical Trials: A Systematic Review

Introduction:

Some medicinal plants have shown promising therapeutic potential for the management of the diseases. We aimed to systematically review the literature wherein the therapeutic effects of saffron have been studied on eye disorders.

Methods

A systematic literature search was performed in PubMed, Scopus, Web of Science, Google scholar and other databases using eye disorders and saffron as key terms. No strict inclusion criteria were defined, and almost all clinical studies, as well as in vivo and in vitro studies were included. The reported data in each study were extracted and then qualitatively described.

Results

Finally, 78 articles were found but only 29 relevant articles were included. Nine articles were clinical trials and 20 articles were studies conducted on cellular and molecular aspects of saffron on eye disorders. According to the included studies, crocin prevented the pro-inflammatory response in retinal cells and decreased glucose levels in diabetic mice. Also, crocetin prevented retinal degeneration and saffron protected photoreceptors from light-induced damage in retinal cells. Saffron also improved visual function in age-related macular edema and decreased intraocular pressure in patients with glaucoma. In addition, it was shown that crocin can improve best corrected visual acuity and decrease central macular thickness in patients with diabetic maculopathy.

Conclusion

The results of this review indicated that saffron and its main ingredients such as crocin could be a potential candidate for the treatment of ocular disease especially eye inflammation; however, further clinical studies are needed to confirm such efficiency.

Medicinal plants and natural products as neuroprotective agents in age-related macular degeneration

The retina may suffer neurodegenerative damages, as other tissues of the central nervous system do, and serious eye diseases may develop. One of them is age-related macular degeneration, which causes progressive loss of vision due to retina degeneration. Treatment of age-related macular degeneration focuses on antioxidant agents and anti-vascular endothelial growth factor compounds, among others, that prevent/diminish oxidative stress and reduce neovascularisation respectively. The phytochemicals, medicinal plants and/or plant-diet supplements might be a useful adjunct in prevention or treatment of age-related macular degeneration owing to their antioxidant and anti-vascular endothelial growth factor properties. This review article presents the most investigated plants and natural products in relation to age-related macular degeneration, such as saffron, ginkgo, bilberry and blueberry, curcuma or turmeric, carotenoids, polyphenols, and vitamins C and E. This study provides up-to-date information on the effects, treatments, safety and efficiency of these phytotherapy products.

An Open-Label Pilot Study on Macumax Supplementation for Dry-Type Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is one of the most widespread degenerative disorders in elderly people. A 90-day, open-label clinical study was conducted in 40 patients, aged 50 years or older, with early-stage dry-type AMD to evaluate the safety and efficacy of Macumax^®, a novel mixture of a phyto-mineral nutritional supplement containing ZeaLutein^® (consisting of lutein, zeaxanthin, and piperine), extracts of bilberry, saffron, and zinc monomethionine. Subjects received one capsule of the supplement twice daily for 90 days. The treatment measures included physical examination, vital signs, and assessment of subjective and objective symptoms at baseline and after treatment. For efficacy assessment, baseline values were compared with the values after treatment at 30-day intervals, on days 30, 60, and 90. The safety of the treatment was assessed during all the visits. Overall, the patients showed improvement in the subjective symptoms, such as vision scores after treatment compared with baseline. The changes in diminished and distorted vision scores were found to be significant from day 60 (P < .05). In the case of objective symptoms, only 40% of the subjects (P < .05) had abnormal Amsler's grid aberration scores on day 90 compared with 77.5% of subjects at the beginning of the study. No adverse events were observed during the study. This pilot study provides evidence that Macumax^® supplementation is safe and maintained eye health without further progression of the disease in patients with early-stage dry-type AMD. Clinical Trial Registration number: CTRI/2016/02/006676

Crocetin Prevents RPE Cells from Oxidative Stress through Protection of Cellular Metabolic Function and Activation of ERK1/2

Age-related macular degeneration (AMD) is a leading cause for visual impairment in aging populations with limited established therapeutic interventions available. Oxidative stress plays an essential role in the pathogenesis of AMD, damaging the retinal pigment epithelium (RPE), which is essential for the function and maintenance of the light-sensing photoreceptors. This study aimed to evaluate the effects of crocetin, one of the main components of Saffron, on an in vitro RPE model of tert-butyl hydroperoxide (TBHP) induced oxidative stress using ARPE19 cells. The effects of crocetin were assessed using lactate de-hydrogenase (LDH) and ATP assays, as well as immunocytochemistry for cell morphology, junctional integrity, and nuclear morphology. The mechanism of crocetin action was determined via assessment of energy production pathways, including mitochondrial respiration and glycolysis in real-time as well as investigation of extracellular signal-regulated kinase 1/2 (ERK1/2) activation and distribution. Our results show that crocetin pre-treatment protects ARPE19 cells from TBHP-induced LDH release, intracellular ATP depletion, nuclear condensation, and disturbance of junctional integrity and cytoskeleton. The protective effect of crocetin is mediated via the preservation of energy production pathways and activation of ERK1/2 in the first minutes of TBHP exposure to potentiate survival pathways. The combined data suggest that a natural antioxidant, such as crocetin, represents a promising candidate to prevent oxidative stress in RPE cells and might halt or delay disease progression in AMD.

Beneficial effects of saffron (Crocus sativus L.) in ocular pathologies, particularly neurodegenerative retinal diseases

Saffron (Crocus sativus L.) has been traditionally used in food preparation and as a medicinal plant. It currently has numerous therapeutic properties attributed to it, such as protection against ischemia, as well as anticonvulsant, antidepressant, anxiolytic, hypolipidemic, anti-atherogenic, anti-hypertensive, antidiabetic, and anti-cancer properties. In addition, saffron has remarkable beneficial properties, such as anti-apoptotic, anti-inflammatory and antioxidant activities, due to its main metabolites, among which crocin and crocetin stand out. Furthermore, increasing evidence underwrites the possible neuroprotective role of the main bioactive saffron constituents in neurodegenerative diseases, such as Parkinson’s and Alzheimer’s diseases, both in experimental models and in clinical studies in patients. Currently, saffron supplementation is being tested for ocular neurodegenerative pathologies, such as diabetic retinopathy, retinitis pigmentosa, age-related macular degeneration and glaucoma, among others, and shows beneficial effects. The present article provides a comprehensive and up to date report of the investigations on the beneficial effects of saffron extracts on the main neurodegenerative ocular pathologies and other ocular diseases. This review showed that saffron extracts could be considered promising therapeutic agents to help in the treatment of ocular neurodegenerative diseases.

Saffron: A Multitask Neuroprotective Agent for Retinal Degenerative Diseases

Both age related macular degeneration (AMD) and light induced retinal damage share the common major role played by oxidative stress in the induction/progression of degenerative events. Light damaged (LD) rats have been widely used as a convenient model to gain insight into the mechanisms of degenerative disease, to enucleate relevant steps and to test neuroprotectants. Among them, saffron has been shown to ameliorate degenerative processes and to regulate many genes and protective pathways. Saffron has been also tested in AMD patients. We extended our analysis to a possible additional effect regulated by saffron and compared in AMD patients a pure antioxidant treatment (Lutein/zeaxanthin) with saffron treatment. Methods: Animal model. Sprague-Dawley (SD) adult rats, raised at 5 lux, were exposed to 1000 lux for 24 h and then either immediately sacrificed or placed back at 5 lux for 7 days recovery period. A group of animals was treated with saffron. We performed in the animal model: (1) SDS-PAGE analysis; (2) Western Blotting (3) Enzyme activity assay (4) Immunolabelling; in AMD patients: a longitudinal open-label study 29 (±5) months in two groups of patients: lutein/zeaxanthin (19) and saffron (23) treated. Visual function was tested every 8 months by ERG recordings in addition to clinical examination. Results: Enzymatic activity of MMP-3 is reduced in LD saffron treated retinas and is comparable to control as it is MMP-3 expression. LD treated retinas do not present "rosettes" and microglia activation and migration is highly reduced. Visual function remains stable in saffron treated AMD patients while deteriorates in the lutein/zeaxanthin group. Conclusion: Our results provide evidence of an additional way of action of saffron treatment confirming the complex nature of neuroprotective activities of its chemical components. Accordingly, long term follow-up in AMD patients reveals an added value of saffron supplementation treatment compared to classical antioxidant protocol.

Treatments for dry age-related macular degeneration and Stargardt disease: a systematic review

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of visual loss in older people. Advanced AMD takes two forms, neovascular (wet) and atrophic (dry). Stargardt disease (STGD) is the commonest form of inherited macular dystrophy.

OBJECTIVE

To carry out a systematic review of treatments for dry AMD and STGD, and to identify emerging treatments where future NIHR research might be commissioned.

DESIGN

Systematic review.

METHODS

We searched MEDLINE, EMBASE, Web of Science and The Cochrane Library from 2005 to 13 July 2017 for reviews, journal articles and meeting abstracts. We looked for studies of interventions that aim to preserve or restore vision in people with dry AMD or STGD. The most important outcomes are those that matter to patients: visual acuity (VA), contrast sensitivity, reading speed, ability to drive, adverse effects of treatment, quality of life, progression of disease and patient preference. However, visual loss is a late event and intermediate predictors of future decline were accepted if there was good evidence that they are strong predictors of subsequent visual outcomes. These include changes detectable by investigation, but not necessarily noticed by people with AMD or STGD. ClinicalTrials.gov, the World Health Organization search portal and the UK Clinical Trials gateway were searched for ongoing and recently completed clinical trials.

RESULTS

The titles and abstracts of 7948 articles were screened for inclusion. The full text of 398 articles were obtained for further screening and checking of references and 112 articles were included in the final report. Overall, there were disappointingly few good-quality studies (including of sufficient size and duration) reporting useful outcomes, particularly in STGD. However we did identify a number of promising research topics, including drug treatments, stem cells, new forms of laser treatment, and implantable intraocular lens telescopes. In many cases, research is already under way, funded by industry or governments.

LIMITATIONS

In AMD, the main limitation came from the poor quality of much of the evidence. Many studies used VA as their main outcome despite not having sufficient duration to observe changes. The evidence on treatments for STGD is sparse. Most studies tested interventions with no comparison group, were far too short term, and the quality of some studies was poor.

FUTURE WORK

We think that the topics on which the Health Technology Assessment (HTA) and Efficacy Mechanism and Evaluation (EME) programmes might consider commissioning primary research are in STGD, a HTA trial of fenretinide (ReVision Therapeutics, San Diego, CA, USA), a visual cycle inhibitor, and EME research into the value of lutein and zeaxanthin supplements, using short-term measures of retinal function. In AMD, we suggest trials of fenretinide and of a potent statin. There is epidemiological evidence from the USA that the drug, levodopa, used for treating Parkinson's disease, may reduce the incidence of AMD. We suggest that similar research should be carried out using the large general practice databases in the UK. Ideally, future research should be at earlier stages in both diseases, before vision is impaired, using sensitive measures of macular function. This may require early detection of AMD by screening.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016038708.

FUNDING

The National Institute for Health Research HTA programme.

Saffron (Crocus sativus L.) in Ocular Diseases: A Narrative Review of the Existing Evidence from Clinical Studies

Saffron (Crocus sativus L.) and its main constituents, i.e., crocin and crocetin, are natural carotenoid compounds, which have been reported to possess a wide spectrum of properties and induce pleiotropic anti-inflammatory, anti-oxidative, and neuroprotective effects. An increasing number of experimental, animal, and human studies have investigated the effects and mechanistic pathways of these compounds in order to assess their potential therapeutic use in ocular diseases (e.g., in age related macular degeneration, glaucoma, and diabetic maculopathy). This narrative review presents the key findings of published clinical studies that examined the effects of saffron and/or its constituents in the context of ocular disease, as well as an overview of the proposed underlying mechanisms mediating these effects.

The Effect of Saffron on Depression among Recovered Consumers of Methamphetamine Living with HIV/AIDS

BACKGROUND

From one hand, depression is one of the symptoms that occur after abstinence from methamphetamine. On the other people living with HIV/AIDS are in isolation due to the nature of their illness and depression is one of the most common mental health problems they experience.

OBJECTIVES

This study was aimed at determining the effectiveness of saffron on reducing depression among recovered consumers of methamphetamine living with HIV/AIDS.

METHODS

The design of this study was semi-experimental with pre-test, post-test and control (placebo) groups. The statistical population consisted of all recovered consumers of methamphetamine living with HIV/AIDS who were referred to the Positive Club. Fifty-seven (57) recovered consumers of methamphetamine, living with HIV/AIDS, were selected by convenience sampling method. They were randomly assigned to an experimental (saffron) group and a control (placebo) group. The experimental group received 30 ml of saffron per day for 8 weeks, whereas the control (placebo) group received placebo the same way. BDI-II was used in this study as a measurement instrument. ANCOVA models were used for statistical inference.

RESULTS

The findings showed that saffron and its ingredients had been effective in reducing depression among this group (P < 0.05).

CONCLUSION

In fact, saffron with its active ingredients (Crusin and Saffranal) by serotonin and dopamine secretion in the brain, help in reducing depression among recovered consumers of methamphetamine living with HIV/AIDS.

Acquired Resilience: An Evolved System of Tissue Protection in Mammals

This review brings together observations on the stress-induced regulation of resilience mechanisms in body tissues. It is argued that the stresses that induce tissue resilience in mammals arise from everyday sources: sunlight, food, lack of food, hypoxia and physical stresses. At low levels, these stresses induce an organised protective response in probably all tissues; and, at some higher level, cause tissue destruction. This pattern of response to stress is well known to toxicologists, who have termed it hormesis. The phenotypes of resilience are diverse and reports of stress-induced resilience are to be found in journals of neuroscience, sports medicine, cancer, healthy ageing, dementia, parkinsonism, ophthalmology and more. This diversity makes the proposing of a general concept of induced resilience a significant task, which this review attempts. We suggest that a system of stress-induced tissue resilience has evolved to enhance the survival of animals. By analogy with acquired immunity, we term this system 'acquired resilience'. Evidence is reviewed that acquired resilience, like acquired immunity, fades with age. This fading is, we suggest, a major component of ageing. Understanding of acquired resilience may, we argue, open pathways for the maintenance of good health in the later decades of human life.

Effects of Crocin on Diabetic Maculopathy: A Placebo-Controlled Randomized Clinical Trial

OBJECTIVE

Diabetic macular edema (DME) is one of the most important sight-threatening complications in patients with diabetes. Owing to neuroprotective properties, crocin, as the main constituent in saffron, is thought to be useful in the treatment and prevention of diabetic maculopathy. The aim of this trial was to evaluate the effects of crocin as a supplement on reducing inflammation in patients with diabetic maculopathy.

DESIGN

Double-masked, placebo controlled, phase 2 randomized clinical trial.

METHODS

Participants: In this study, 101 eyes of 60 patients with refractory diabetic maculopathy to conventional therapy including macular photocoagulation and intravitreal injection of anti-vascular endothelial growth factor agent (bevacizumab) with or without steroid (triamcinolone) were studied in 3 groups.

INTERVENTION

Patients in the crocin groups received 5 mg or 15 mg crocin tablets per day for 3 months, whereas patients in the placebo group received 1 placebo tablet per day during the study. The best-corrected visual acuity (BCVA) and central macular thickness (CMT) were measured before, every month during, and 3 months after intervention. Biochemical blood tests were also evaluated before and after trial.

MAIN OUTCOME MEASURES

The BCVA and CMT were evaluated as the primary outcomes, whereas HbA1c and fasting blood sugar (FBS) were studied as the secondary outcomes in this trial.

RESULTS

One hundred and one eyes were enrolled in this trial and were divided into 3 groups (crocin 5 mg, n = 34; crocin 15 mg, n = 33; and placebo, n = 34). According to our data, administration of crocin 15 mg tablet per day could significantly decrease HbA1c (P value = .024; 95% confidence interval [CI] 0.3-0.96), and CMT (P value = .005; 95% CI, 32.75-126.99) and improve BCVA (logMAR changes; P value = .012; 95% CI, 0.23-0.69) compared to the placebo group. Although administration of crocin 5 mg tablet per day could clinically improve HbA1c, FBS, CMT, and BCVA, the difference was not significant compared to the placebo group.

CONCLUSION

This study indicated the effect of crocin as a potent antioxidant and neuroprotective for treatment of refractory DME in the short term; however, the clinical significance is yet to be proved in a study with larger sample size and longer duration of follow-up and also in treatment-naïve patients.

Neuroprotection by (endo)Cannabinoids in Glaucoma and Retinal Neurodegenerative Diseases

BACKGROUND

Emerging neuroprotective strategies are being explored to preserve the retina from degeneration, that occurs in eye pathologies like glaucoma, diabetic retinopathy, age-related macular degeneration, and retinitis pigmentosa. Incidentally, neuroprotection of retina is a defending mechanism designed to prevent or delay neuronal cell death, and to maintain neural function following an initial insult, thus avoiding loss of vision.

METHODS

Numerous studies have investigated potential neuroprotective properties of plant-derived phytocannabinoids, as well as of their endogenous counterparts collectively termed endocannabinoids (eCBs), in several degenerative diseases of the retina. eCBs are a group of neuromodulators that, mainly by activating G protein-coupled type-1 and type-2 cannabinoid (CB1 and CB2) receptors, trigger multiple signal transduction cascades that modulate central and peripheral cell functions. A fine balance between biosynthetic and degrading enzymes that control the right concentration of eCBs has been shown to provide neuroprotection in traumatic, ischemic, inflammatory and neurotoxic damage of the brain.

RESULTS

Since the existence of eCBs and their binding receptors was documented in the retina of numerous species (from fishes to primates), their involvement in the visual processing has been demonstrated, more recently with a focus on retinal neurodegeneration and neuroprotection.

CONCLUSION

The aim of this review is to present a modern view of the endocannabinoid system, in order to discuss in a better perspective available data from preclinical studies on the use of eCBs as new neuroprotective agents, potentially useful to prevent glaucoma and retinal neurodegenerative diseases.

Plant Polyphenols and Exendin-4 Prevent Hyperactivity and TNF-α Release in LPS-Treated In vitro Neuron/Astrocyte/Microglial Networks

Increasing evidence supports a decisive role for neuroinflammation in the neurodegenerative process of several central nervous system (CNS) disorders. Microglia are essential mediators of neuroinflammation and can regulate a broad spectrum of cellular responses by releasing reactive oxygen intermediates, nitric oxide, proteases, excitatory amino acids, and cytokines. We have recently shown that also in ex-vivo cortical networks of neurons, astrocytes and microglia, an increased level of tumor necrosis factor-alpha (TNF-α) was detected a few hours after exposure to the bacterial endotoxin lipopolysaccharide (LPS). Simultaneously, an atypical “seizure-like” neuronal network activity was recorded by multi-electrode array (MEA) electrophysiology. These effects were prevented by minocycline, an established anti-inflammatory antibiotic. We show here that the same inhibitory effect against LPS-induced neuroinflammation is exerted also by natural plant compounds, polyphenols, such as curcumin (CU, curcuma longa), crocin (CR, saffron), and resveratrol (RE, grape), as well as by the glucagon like peptide-1 receptor (GLP-1R) agonist exendin-4 (EX-4). The drugs tested also caused per-se early transient (variable) changes of network activity. Since it has been reported that LPS-induced neuroinflammation causes rearrangements of glutamate transporters in astrocytes and microglia, we suggest that neural activity could be putatively increased by an imbalance of glial glutamate transporter activity, leading to prolonged synaptic glutamatergic dysregulation.

Efficacy and Safety of Saffron Supplementation: Current Clinical Findings

Saffron (Crocus savitus) is a Middle-Eastern herb with strong antioxidant properties. Its major constituents, safranal, crocin, and crocetin, are also antioxidants and bear structural similarities to other well-known natural antixodant substances, such as zeaxanthin. Given the role of oxidative stress in many diseases, considerable interest has been shown into the potential role of saffron supplementation as a treatment for a range of diseases. In vitro and animal studies have provided evidence that saffron and its constituents may be potent therapies for a range of pathologies, including Alzheimer's disease, age-related macular degeneration (AMD) and cardiac ischemia. Whether these findings translate into clinical efficacy, however, has as of yet been incompletely assessed. This makes assessing the role of saffron supplementation in these diseases difficult. Here, we review the current human clinical evidence supporting saffron supplementation as a treatment for a range of pathologies and the underlying science supporting its use.

Modulation of Type-1 and Type-2 Cannabinoid Receptors by Saffron in a Rat Model of Retinal Neurodegeneration

Experimental studies demonstrated that saffron (Crocus sativus) given as a dietary supplement counteracts the effects of bright continuous light (BCL) exposure in the albino rat retina, preserving both morphology and function and probably acting as a regulator of programmed cell death [1]. The purpose of this study was to ascertain whether the neuroprotective effect of saffron on rat retina exposed to BCL is associated with a modulation of the endocannabinoid system (ECS). To this aim, we used eight experimental groups of Sprague-Dawley rats, of which six were exposed to BCL for 24 hours. Following retinal function evaluation, retinas were quickly removed for biochemical and morphological analyses. Rats were either saffron-prefed or intravitreally injected with selective type-1 (CB1) or type-2 (CB2) cannabinoid receptor antagonists before BCL. Prefeeding and intravitreally injections were combined in two experimental groups before BCL. BCL exposure led to enhanced gene and protein expression of retinal CB1 and CB2 without affecting the other ECS elements. This effect of BCL on CB1 and CB2 was reversed by saffron treatment. Selective CB1 and CB2 antagonists reduced photoreceptor death, preserved morphology and visual function of retina, and mitigated the outer nuclear layer (ONL) damage due to BCL. Of interest, CB2-dependent neuroprotection was more pronounced than that conferred by CB1. These data suggest that BCL modulates only distinct ECS elements like CB1 and CB2, and that saffron and cannabinoid receptors could share the same mechanism in order to afford retinal protection.

Widespread brain transcriptome alterations underlie the neuroprotective actions of dietary saffron

Dietary saffron has shown promise as a neuroprotective intervention in clinical trials of retinal degeneration and dementia and in animal models of multiple CNS disorders, including Parkinson's disease. This therapeutic potential makes it important to define the relationship between dose and protection and the mechanisms involved. To explore these two issues, mice were pre-conditioned by providing an aqueous extract of saffron (0.01% w/v) as their drinking water for 2, 5 or 10 days before administration of the parkinsonian neurotoxin MPTP (50 mg/kg). Five days of saffron pre-conditioning provided the greatest benefit against MPTP-induced neuropathology, significantly mitigating both loss of functional dopaminergic cells in the substantia nigra pars compacta (p < 0.01) and abnormal neuronal activity in the caudate-putamen complex (p < 0.0001). RNA microarray analysis of the brain transcriptome of mice pre-conditioned with saffron for 5 days revealed differential expression of 424 genes. Bioinformatics analysis identified enrichment of molecular pathways (e.g. adherens junction, TNFR1 and Fas signaling) and expression changes in candidate genes (Cyr61, Gpx8, Ndufs4, and Nos1ap) with known neuroprotective actions. The apparent biphasic nature of the dose-response relationship between saffron and measures of neuroprotection, together with the stress-inducible nature of many of the up-regulated genes and pathways, lend credence to the idea that saffron, like various other phytochemicals, is a hormetic stimulus, with functions beyond its strong antioxidant capacity. These findings provide impetus for a more comprehensive evaluation of saffron as a neuroprotective intervention.

Saffron reduces ATP-induced retinal cytotoxicity by targeting P2X7 receptors

P2X7-type purinergic receptors are distributed throughout the nervous system where they contribute to physiological and pathological functions. In the retina, this receptor is found in both inner and outer cells including microglia modulating signaling and health of retinal cells. It is involved in retinal neurodegenerative disorders such as retinitis pigmentosa and age-related macular degeneration (AMD). Experimental studies demonstrated that saffron protects photoreceptors from light-induced damage preserving both retinal morphology and visual function and improves retinal flicker sensitivity in AMD patients. To evaluate a possible interaction between saffron and P2X7 receptors (P2X7Rs), different cellular models and experimental approaches were used. We found that saffron positively influences the viability of mouse primary retinal cells and photoreceptor-derived 661W cells exposed to ATP, and reduced the ATP-induced intracellular calcium increase in 661W cells. Similar results were obtained on HEK cells transfected with recombinant rat P2X7R but not on cells transfected with rat P2X2R. Finally, patch-clamp experiments showed that saffron inhibited cationic currents in HEK-P2X7R cells. These results point out a novel mechanism through which saffron may exert its protective role in neurodegeneration and support the idea that P2X7-mediated calcium signaling may be a crucial therapeutic target in the treatment of neurodegenerative diseases.

A systematic review of randomized controlled trials examining the effectiveness of saffron (Crocus sativus L.) on psychological and behavioral outcomes

BACKGROUND

Throughout the past three decades, increased scientific attention has been given to examining saffron's (Crocus sativus L.) use as a potential therapeutic or preventive agent for a number of health conditions, including cancer, cardiovascular disease, and depression.

OBJECTIVE

The purpose of this systematic review is to examine and categorize the current state of scientific evidence from randomized controlled trials (RCTs) regarding the efficacy of saffron on psychological/behavioral outcomes.

SEARCH STRATEGY

Electronic and non-electronic systematic searches were conducted to identify all relevant human clinical research on saffron. The search strategy was extensive and was designed according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)." Reference lists of articles that met the inclusion criteria were searched. Only English language studies were reviewed.

INCLUSION CRITERIA

Saffron trials in combination with other substances and saffron safety studies were considered, in accordance with the PRISMA statement. Included studies must have a control group. Included studies must measure a physiological and/or a behavioral outcome.

DATA EXTRACTION AND ANALYSIS

The methodological quality of all included studies was independently evaluated by two reviewers using the Jadad score. Mean scores and P-values of measures were compared both inter- and intra-study for each parameter (i.e., depression).

RESULTS

Twelve studies met our inclusion criteria. These studies examined the effects of saffron on psychological/behavioral outcomes of: major depressive disorder (n=6), premenstrual syndrome (n = 1), sexual dysfunction and infertility (n=4), and weight loss/snacking behaviors (n=1). The data from these studies support the efficacy of saffron as compared to placebo in improving the following conditions: depressive symptoms (compared to anti-depressants and placebo), premenstrual symptoms, and sexual dysfunction. In addition, saffron use was also effective in reducing excessive snacking behavior.

CONCLUSION

Findings from initial clinical trials suggest that saffron may improve the symptoms and the effects of depression, premenstrual syndrome, sexual dysfunction and infertility, and excessive snacking behaviors. Larger multi-site clinical trials are needed to extend these preliminary findings.

Combining neuroprotectants in a model of retinal degeneration: no additive benefit

The central nervous system undergoing degeneration can be stabilized, and in some models can be restored to function, by neuroprotective treatments. Photobiomodulation (PBM) and dietary saffron are distinctive as neuroprotectants in that they upregulate protective mechanisms, without causing measurable tissue damage. This study reports a first attempt to combine the actions of PBM and saffron. Our working hypothesis was that the actions of PBM and saffron in protecting retinal photoreceptors, in a rat light damage model, would be additive. Results confirmed the neuroprotective potential of each used separately, but gave no evidence that their effects are additive. Detailed analysis suggests that there is actually a negative interaction between PBM and saffron when given simultaneously, with a consequent reduction of the neuroprotection. Specific testing will be required to understand the mechanisms involved and to establish whether there is clinical potential in combining neuroprotectants, to improve the quality of life of people affected by retinal pathology, such as age-related macular degeneration, the major cause of blindness and visual impairment in older adults.

Saffron and retina: neuroprotection and pharmacokinetics

Age-related macular degeneration (AMD) is a retinal neurodegenerative disease whose development and progression are the results of a complex interaction between genetic and environmental risk factors. Both oxidative stress and chronic inflammation play a significant role in the pathogenesis of AMD. Experimental studies in rats with light-induced photoreceptors degeneration demonstrated that saffron may protect photoreceptor from retinal stress, preserving both morphology and function and probably acting as a regulator of programmed cell death, in addition to its antioxidant and anti-inflammatory properties. Recently, a randomized clinical trial showed that in patients with early AMD, dietary supplementation with saffron was able to improve significantly the retinal flicker sensitivity suggesting neuroprotective effect of the compound. Here, we examine the progress of saffron dietary supplementation both in animal model and AMD patients, and discuss the potential and safety for using dietary saffron to treat retinal degeneration.