Antioxidant Properties of Crocus Sativus L. and Its Constituents and Relevance to Neurodegenerative Diseases; Focus on Alzheimer's and Parkinson's Disease

Neuroprotective Action of Selected Natural Drugs Against Neurological Diseases and Mental Disorders: Potential Use Against Radiation Damage

Exposure to radiation, ionizing and non-ionizing radiation, is a significant concern in modern society. The brain is the organ that is most sensitive to radiation exposure. This review describes how exposure to radiation can affect neurotransmitters in different brain regions, affecting brain function. This review covers neurodegenerative diseases such as Alzheimer's, Parkinson's, and neuroinflammation due to changes in neurons in the central nervous system, and the effects thereon of medicinal plants such as Allium cepa, Allium sativum, Centella asiatica, Coriandrum sativum, and Crocus sativus plants, used for centuries in traditional medicine. These herbal medicines exert free radical scavenging, and antioxidant as well as anti-inflammatory properties which can be beneficial in managing neurological diseases. The present review compiles the neuroprotective effects of selected natural plants against neurological damage, as well as highlights the different mechanisms of action elicited to induce and produce beneficial effects. The current review describes recent studies on the pharmacological effects of neuroprotective herbs on various neurological and mental illnesses, and shows the way further studies can impact this field, including potential effects on radiation-induced damage.

A marine-derived antioxidant astaxanthin as a potential neuroprotective and neurotherapeutic agent: A review of its efficacy on neurodegenerative conditions

Astaxanthin is a potent lipid-soluble carotenoid produced by several different freshwater and marine microorganisms, including microalgae, bacteria, fungi, and yeast. The proven therapeutic effects of astaxanthin against different diseases have made this carotenoid popular in the nutraceutical market and among consumers. Recently, astaxanthin is also receiving attention for its effects in the co-adjuvant treatment or prevention of neurological pathologies. In this systematic review, studies evaluating the efficacy of astaxanthin against different neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, cerebrovascular diseases, and spinal cord injury are analyzed. Based on the current literature, astaxanthin shows potential biological activity in both in vitro and in vivo models. In addition, its preventive and therapeutic activities against the above-mentioned diseases have been emphasized in studies with different experimental designs. In contrast, none of the 59 studies reviewed reported any safety concerns or adverse health effects as a result of astaxanthin supplementation. The preventive or therapeutic role of astaxanthin may vary depending on the dosage and route of administration. Although there is a consensus in the literature regarding its effectiveness against the specified diseases, it is important to determine the safe intake levels of synthetic and natural forms and to determine the most effective forms for oral intake.

Myricetin mitigates motor disturbance and decreases neuronal ferroptosis in a rat model of Parkinson's disease

Ferroptosis is an iron-dependent cell death form characterized by reactive oxygen species (ROS) overgeneration and lipid peroxidation. Myricetin, a flavonoid that exists in numerous plants, exhibits potent antioxidant capacity. Given that iron accumulation and ROS-provoked dopaminergic neuron death are the two main pathological hallmarks of Parkinson's disease (PD), we aimed to investigate whether myricetin decreases neuronal death through suppressing ferroptosis. The PD models were established by intraperitoneally injecting 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) into rats and by treating SH-SY5Y cells with 1-methyl-4-phenylpyridinium (MPP+), respectively. Ferroptosis was identified by assessing the levels of Fe2+, ROS, malondialdehyde (MDA), and glutathione (GSH). The results demonstrated that myricetin treatment effectively mitigated MPTP-triggered motor impairment, dopamine neuronal death, and α-synuclein (α-Syn) accumulation in PD models. Myricetin also alleviated MPTP-induced ferroptosis, as evidenced by decreased levels of Fe2+, ROS, and MDA and increased levels of GSH in the substantia nigra (SN) and serum in PD models. All these changes were reversed by erastin, a ferroptosis activator. In vitro, myricetin treatment restored SH-SY5Y cell viability and alleviated MPP+-induced SH-SY5Y cell ferroptosis. Mechanistically, myricetin accelerated nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and subsequent glutathione peroxidase 4 (Gpx4) expression in MPP+-treated SH-SY5Y cells, two critical inhibitors of ferroptosis. Collectively, these data demonstrate that myricetin may be a potential agent for decreasing dopaminergic neuron death by inhibiting ferroptosis in PD.

Distribution of Main Bioactive Compounds from Saffron Species as a Function of Infusion Temperature and Time in an Oil/Water System

Most research on saffron has focused on its composition and beneficial effects, while the culinary perspective to enhance its gastronomic potential remains unexplored. This study aims to define the transfer of the main compounds responsible for color, flavor, and aromatic properties, evaluating three critical variables: temperature (60 °C, 80 °C and 100 °C), infusion time (ranging from 10 to 30 min), and the composition of the medium (water, oil, and water/oil). Samples were analyzed using the LC-QTOF MS/MS and ISO 3632-1:2011 methods. The major compounds were crocins, including trans-crocin and picrocrocin. Among the flavonoids, kaempferol 3-O-sophoroside stands out. Regarding extraction conditions, crocins, glycoside flavonoids, and picrocrocin were enhanced in water, the former in 100% water and at low temperatures, while picrocrocin proved to be the most stable compound with extraction favored at high temperatures. The variable with the greatest incidence of picrocrocin isolation seemed to be the concentration of water since water/oil compositions reported higher concentrations. Safranal and kaempferol were enriched in the oil phase and at lower temperatures. This study provides a chemical interpretation for the appropriate gastronomic use of saffron according to its versatility. Finally, the determination of safranal using the ISO method did not correlate with that obtained using chromatography.

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.

In silico and pharmacokinetic studies of glucomoringin from Moringa oleifera root for Alzheimer's disease like pathology

Aim: The aim of this research is to investigate the potential of glucomoringin, derived from Moringa oleifera, as a therapeutic agent for Alzheimer's disease through in silico analysis. Materials & methods: This study employs in silico or computational methodologies, including pkCSM, Swiss ADME, OSIRIS® property explorer, PASS online web resource and MOLINSPIRATION® software, to predict the pharmacokinetic characteristics and biological activity of glucomoringin. Results & conclusion: Molecular docking indicates strong binding to I-1β and the pharmacokinetic profile shows cytochrome P450 enzyme inhibition, prompting further research for dosing strategies. Toxicological predictions affirm safety, while bioactivity assessments demonstrate versatility in modulating essential pathways. glucomoringin's potential for Alzheimer's treatment, emphasizing the need for additional empirical research.

New horizons for the study of saffron (Crocus sativus L.) and its active ingredients in the management of neurological and psychiatric disorders: A systematic review of clinical evidence and mechanisms

Saffron (Crocus sativus), as an herbal medicine, has been extensively investigated for treating neurological and psychiatric disorders. This systematic review aimed to assess the overall effects of saffron on cognition, depression, anxiety, sleep disorders, attention-deficit/hyperactivity disorder (ADHD), and obsessive-compulsive disorder (OCD). Relevant randomized controlled trials (RCTs) were identified by searching PubMed/Medline, Web of Science, and Clinical Trials databases up to June 2023 according to search terms and inclusion criteria. The participants were either healthy or suffering from some diseases, including neurological and psychiatric disorders, and consumed saffron or its extracts as an intervention. The risk of bias was assessed according to the Cochrane guidelines, and the PRISMA statement was followed. The meta-analysis was performed using RevMan and STATA software. A random-effects or fixed-effects model was used to calculate the pooled effect sizes. Forty-six RCTs were enrolled, and the duration of these trials ranged from 4 to 48 weeks with saffron or its extracts, both alone or in combination with conventional drugs. Saffron was more effective than placebo in improving cognition, depression with an overall effect size of -4.26 (95% CI: -5.76, -2.77), anxiety of -3.75 (95% CI: -5.83, -1.67), and sleep disorders of -1.91 (95% CI: -2.88, -0.93). Saffron was non-inferior to conventional drugs for treating cognitive disorders, depression, anxiety, ADHD, and OCD, and it exhibited good tolerance with few side effects. Saffron may exert protective roles for neurological and psychiatric disorders and represents a relatively favorable and safe treatment.

Hormetic Nutrition and Redox Regulation in Gut-Brain Axis Disorders

The antioxidant and anti-inflammatory effects of hormetic nutrition for enhancing stress resilience and overall human health have received much attention. Recently, the gut-brain axis has attracted prominent interest for preventing and therapeutically impacting neuropathologies and gastrointestinal diseases. Polyphenols and polyphenol-combined nanoparticles in synergy with probiotics have shown to improve gut bioavailability and blood-brain barrier (BBB) permeability, thus inhibiting the oxidative stress, metabolic dysfunction and inflammation linked to gut dysbiosis and ultimately the onset and progression of central nervous system (CNS) disorders. In accordance with hormesis, polyphenols display biphasic dose-response effects by activating at a low dose the Nrf2 pathway resulting in the upregulation of antioxidant vitagenes, as in the case of heme oxygenase-1 upregulated by hidrox® or curcumin and sirtuin-1 activated by resveratrol to inhibit reactive oxygen species (ROS) overproduction, microbiota dysfunction and neurotoxic damage. Importantly, modulation of the composition and function of the gut microbiota through polyphenols and/or probiotics enhances the abundance of beneficial bacteria and can prevent and treat Alzheimer's disease and other neurological disorders. Interestingly, dysregulation of the Nrf2 pathway in the gut and the brain can exacerbate selective susceptibility under neuroinflammatory conditions to CNS disorders due to the high vulnerability of vagal sensory neurons to oxidative stress. Herein, we aimed to discuss hormetic nutrients, including polyphenols and/or probiotics, targeting the Nrf2 pathway and vitagenes for the development of promising neuroprotective and therapeutic strategies to suppress oxidative stress, inflammation and microbiota deregulation, and consequently improve cognitive performance and brain health. In this review, we also explore interactions of the gut-brain axis based on sophisticated and cutting-edge technologies for novel anti-neuroinflammatory approaches and personalized nutritional therapies.

Research progress on the pharmacological activity, biosynthetic pathways, and biosynthesis of crocins

Crocins are water-soluble apocarotenoids isolated from the flowers of crocus and gardenia. They exhibit various pharmacological effects, including neuroprotection, anti-inflammatory properties, hepatorenal protection, and anticancer activity. They are often used as coloring and seasoning agents. Due to the limited content of crocins in plants and the high cost of chemical synthesis, the supply of crocins is insufficient to meet current demand. The biosynthetic pathways for crocins have been elucidated to date, which allows the heterologous production of these valuable compounds in microorganisms by fermentation. This review article provides a comprehensive overview of the chemistry, pharmacological activity, biosynthetic pathways, and heterologous production of crocins, aiming to lay the foundation for the large-scale production of these valuable natural products by using engineered microbial cell factories.

Natural compounds for oxidative stress and neuroprotection in schizophrenia: composition, mechanisms, and therapeutic potential

OBJECTIVE

An imbalance between the generation of reactive oxygen species (ROS) and the body's antioxidant defense mechanisms is believed to be a critical factor in the development of schizophrenia (SCZ) like neurological illnesses. Understanding the roles of ROS in the development of SCZ and the potential activity of natural antioxidants against SCZ could lead to more effective therapeutic options for the prevention and treatment of the illness.

METHODS

SCZ is a mental disorder characterised by progressive impairments in working memory, attention, and executive functioning. In present investigation, we summarized the experimental findings for understanding the role of oxidative stress (OS) in the development of SCZ and the potential neuroprotective effects of natural antioxidants in the treatment of SCZ.

RESULTS

Current study supports the use of the mentioned antioxidant natural compounds as a potential therapeutic candidates for the treatment of OS mediated neurodegeneration in SCZ.

DISCUSSION

Elevated levels of harmful ROS and reduced antioxidant defense mechanisms are indicative of increased oxidative stress (OS), which is associated with SCZ. Previous research has shown that individuals with SCZ, including non-medicated, medicated, first-episode, and chronic patients, exhibit decreased levels of total antioxidants and GSH. Additionally, they have reduced antioxidant enzyme levels such as catalase (CAT), glutathione (GPx), and, superoxide dismutase (SOD) and lower serum levels of brain-derived neurotrophic factor (BDNF) in their brain tissue. The mentioned natural antioxidants may assist in reducing oxidative damage in individuals with SCZ and increasing BDNF expression in the brain, potentially improving cognitive function and learning ability.

Valorization of saffron (Crocus sativus L.) stigma as a potential natural antioxidant for soybean (Glycine max L.) oil stabilization

Synthetic antioxidants are known for their efficiency to improve vegetable oil oxidative stability. But owing to their harmful effects on human health, edible oil industry is seeking for safe and healthy natural antioxidants. The present work was setup with the aim of improving soybean oil (SO) oxidative stability by using saffron (Crocus sativus L.) stigmas collected in Morocco. Saffron stigmas were used as a natural antioxidant at various concentrations (0.2, 0.3, and 0.6%) in soybean oil compared to tocobiol (0.3%) as a synthetic antioxidant (the positive control). Performances of such natural and synthetic antioxidants were evaluated by measuring oil basic quality indices under accelerated storage at 60 °C for 12 weeks. Such indices consisted of free fatty acids (FFA), peroxide value (PV), anisidine value (p-AV), total oxidation value (TOTOX), UV extinction coefficients (K232 and K270), fatty acids composition (FA), and iodine value (IV). The obtained data show that there were significant (p < 0.05) increases in FFA, PV, p-AV, K232, K270, and TOTOX but no much variations were observed for FA and IV especially in saffron stigmas fortified oils across storage times. However, in the case of oils fortified with saffron stigmas at different doses, such an increase was of a lesser magnitude (for FFA, PV, p-AV, K270, and TOTOX) as compared to tocobiol. These outcomes were confirmed by principal component analysis with strong positive correlations (p < 0.001) among FFA, PV, p-AV, K232, K270, and TOTOX. The most important, for which determination coefficient R2 > 0.9, were modeled through simple regressions. In conclusion, saffron stigmas with the different doses performed better than the positive control (tocobiol) regardless of the storage time. It could be concluded that saffron stigmas are a promising natural antioxidant, alternative to synthetic antioxidants, to enhance the oxidative stability of edible oils.

Crocin alleviates neurotoxicity induced by bupivacaine in SH-SY5Y cells with inhibition of PI3K/AKT signaling

BACKGROUND

Bupivacaine, a common local anesthetic, can cause neurotoxicity and permanent neurological disorders. Crocin has been widely reported as a potential neuroprotective agent in neural injury models.

OBJECTIVE

The aim of this study was to investigate the role and regulatory mechanism of crocin underlying bupivacaine-induced neurotoxicity.

METHOD

Human neuroblastoma SH-SY5Y cells were treated with bupivacaine and/or crocin for 24 h, followed by detecting cell viability using 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The effect of crocin or bupivacaine on SH-SY5Y cell proliferation was measured by Ki67 immunofluorescence assay. The levels of apoptosis-related proteins and the markers in the PI3K/Akt signaling pathway were examined using western blot analysis. The activities of caspase 3, catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) were tested using respective commercial assay kits. Flow cytometry analysis was executed for detecting SH-SY5Y cell apoptosis.

RESULT

Crocin attenuated bupivacaine-induced neurotoxicity in SH-SY5Y cells. Meanwhile, crocin inhibited SH-SY5Y cell apoptosis induced by bupivacaine via repressing the activity of caspase-3, reducing Bax expression, and elevating Bcl-2 expression. Moreover, crocin mitigated oxidative stress in SH-SY5Y cells by increasing the content of CAT, SOD, GSH-Px and reducing the content of MDA. Additionally, crocin protected against bupivacaine-induced dephosphorylation of Akt and GSK-3β. The protective effects of crocin against bupivacaine-induced neurotoxicity in SH-SY5Y cells were counteracted by the Akt inhibitor.

CONCLUSION

These results suggested that crocin may exert a neuroprotective function by promoting cell proliferation and suppressing apoptosis and oxidative stress in SH-SY5Y cells. Thus, crocin might become a promising drug for the treatment of bupivacaine-induced neurotoxicity.

Role of Network Pharmacology in Prediction of Mechanism of Neuroprotective Compounds

Network pharmacology is an emerging pioneering approach in the drug discovery process, which is used to predict the therapeutic mechanism of compounds using various bioinformatic tools and databases. Emerging studies have indicated the use of network pharmacological approaches in various research fields, particularly in the identification of possible mechanisms of herbal compounds/ayurvedic formulations in the management of various diseases. These techniques could also play an important role in the prediction of the possible mechanisms of neuroprotective compounds. The first part of the chapter includes an introduction on neuroprotective compounds based on literature. Further, network pharmacological approaches are briefly discussed. The use of network pharmacology in the prediction of the neuroprotective mechanism of compounds is discussed in detail with suitable examples. Finally, the chapter concludes with the current challenges and future prospectives.

Crocetin Regulates Functions of Neural Stem Cells to Generate New Neurons for Cerebral Ischemia Recovery

Many neurons undergo apoptosis after ischemic stroke. In the brain, neurogenesis has the potential for neuronal replacement and can be activated by external conditions to repair the injury. Crocetin (CRO), naturally extracted from the plant saffron, acts as a neuroprotective agent for ischemic stroke. However, the underlying mechanism remains unknown. In this work, the effect of CRO on neural stem cell (NSC) behaviors and subventricular zone neurogenesis is investigated. Initially, NSCs are incubated with different concentrations of CRO to detect the cell proliferation and differentiation in vitro. Second, ischemic stroke induced rats are treated with CRO using nimodipine (NMDP) as a comparison. The behavioral functions, infarcted volume, and apoptotic Nissl bodies of rats are noticeably improved after CRO-treatment, comparable to those of NMDP. In addition, the increased regional cerebral blood flow and promoted neuronal differentiation are achieved by CRO-treatment. Brain tissue examination shows significantly increased neuronal regeneration in the focal ischemic injury area. Meanwhile, the length of neurites is prolonged, indicating that CRO could potentially promote neurite extension to enhance cell-cell communication. These findings demonstrate that CRO facilitated the neuronal differentiation of NSCs by activating subventricular zone neurogenesis in damaged cortex and striatum sites to repair ischemic stroke.

Minocycline effects on memory and learning impairment in the beta-amyloid-induced Alzheimer's disease model in male rats using behavioral, biochemical, and histological methods

Alzheimer's disease (AD), as an advanced neurodegenerative disease, is characterized by the everlasting impairment of memory, which is determined by hyperphosphorylation of intracellular Tau protein and accumulation of beta-amyloid (Aβ) in the extracellular space. Minocycline is an antioxidant with neuroprotective effects that can freely cross the blood-brain barrier (BBB). This study investigated the effect of minocycline on the changes in learning and memory functions, activities of blood serum antioxidant enzymes, neuronal loss, and the number of Aβ plaques after AD induced by Aβ in male rats. Healthy adult male Wistar rats (200-220g) were divided randomly into 11 groups (n = 10). The rats received minocycline (50 and 100 mg/kg/day; per os (P.O.)) before, after, and before/after AD induction for 30 days. At the end of the treatment course, behavioral performance was measured by standardized behavioral paradigms. Subsequently, brain samples and blood serum were collected for histological and biochemical analysis. The results indicated that Aβ injection impaired learning and memory performances in the Morris water maze test, reduced exploratory/locomotor activities in the open field test, and enhanced anxiety-like behavior in the elevated plus maze. The behavioral deficits were accompanied by hippocampal oxidative stress (decreased glutathione (GSH) peroxidase enzyme activity and increased malondialdehyde (MDA) levels in the brain (hippocampus) tissue), increased number of Aβ plaques, and neuronal loss in the hippocampus evidenced by Thioflavin S and H&E staining, respectively. Minocycline improved anxiety-like behavior, recovered Aβ-induced learning and memory deficits, increased GSH and decreased MDA levels, and prevented neuronal loss and the accumulation of Aβ plaques. Our results demonstrated that minocycline has neuroprotective effects and can reduce memory dysfunction, which are due to its antioxidant and anti-apoptotic effects.

ROS-sensitive Crocin-loaded chitosan microspheres for lung targeting and attenuation of radiation-induced lung injury

Radiation-induced lung injury (RILI) is one of the major complications in patients exposed to accidental radiation and radiotherapy for thoracic malignancies. However, there is no reliable radioprotector for effective clinical treatment of RILI so far. Herein, a novel Crocin-loaded chitosan microsphere is developed for lung targeting and attenuation of RILI. The chitosan microspheres are modified with 4-carboxyphenylboronic acid and loaded with the natural antioxidant Crocin-I to give the drug-loaded microspheres (~10 μm). The microspheres possess good biocompatibility in vivo and in vitro. In a mouse model, they exhibit effective passive targeting performance and a long retention time in the lung after intravenous administration. Furthermore, they improve the radioprotective effect of Crocin-I for the treatment of RILI by reducing the level of inflammatory cytokines in bronchoalveolar lavage fluid and by regulating oxidative stress in lung tissues. The targeted agents significantly improved the bioavailability and radioprotection of Crocin-I by the outstanding passive targeting effect. This work may provide a promising strategy for efficient radioprotection on RILI using passive lung targeting microspheres.

Design, synthesis and bioevaluation of 1,2,4-thiadiazolidine-3,5-dione derivatives as potential GSK-3β inhibitors for the treatment of Alzheimer's disease

Tideglusib is a non-competitive GSK-3β inhibitor which contain 1,2,4-thiadiazolidine-3,5-dione moiety, and now mainly used for progressive supranuclear palsy due to the lack of some primary cognitive endpoints and secondary endpoints in a phase IIb trail for Alzheimer's disease. Additionally, insufficient evidence exists to support that there are obvious covalent bonds between Tideglusib and GSK-3β. Targeted covalent inhibition strategy could improve the binding efficiency, selectivity and duration of kinase inhibitors. Based on the above premise, two series of targeted compounds with acryloyl warheads were designed and synthesized. The kinase inhibitory activity of the selected compound 10a with better neuroprotective effect improved 2.7 fold than that of Tideglusib. After the preliminary screening of GSK-3β inhibition and neuroprotective activity, the mechanism action of the selected compound 10a was investigated in vitro and in vivo. The results confirmed that 10a with excellent selectivity among the whole tested kinases could significantly reduce the expressions of APP and p-Tau via increasing the level of p-GSK-3β. The pharmacodynamic assay in vivo showed that 10a could markedly improve the learning and memory functions in AD mice induced by AlCl₃ combined with d-galactose. At the same time, the damage of hippocampal neurons in AD mice was obviously reduced. Accordingly, the introduction of acryloyl warheads could increase the GSK-3β inhibitory activity of 1,2,4-thiadiazolidine-3,5-dione derivatives, and the selected compound 10a deserves further research as an effective GSK-3β inhibitor for the potential treatment of AD.

Targeting Mitochondrial Dysfunction in Neurodegenerative Diseases: Expanding the Therapeutic Approaches by Plant-Derived Natural Products

Mitochondria are the primary source of energy production in neurons, supporting the high energy consumption of the nervous system. Inefficient and dysfunctional mitochondria in the central nervous system have been implicated in neurodegenerative diseases. Therefore, targeting mitochondria offers a new therapeutic opportunity for neurodegenerative diseases. Many recent studies have proposed that plant-derived natural products, as pleiotropic, safe, and readily obtainable sources of new drugs, potentially treat neurodegenerative diseases by targeting mitochondria. In this review, we summarize recent advances in targeting mitochondria in neurotherapeutics by employing plant-derived natural products. We discuss the mechanism of plant-derived natural products according to their mechanism of action on mitochondria in terms of regulating biogenesis, fusion, fission, bioenergetics, oxidative stress, calcium homeostasis, membrane potential, and mitochondrial DNA stability, as well as repairing damaged mitochondria. In addition, we discuss the potential perspectives and challenges in developing plant-derived natural products to target mitochondria, highlighting the clinical value of phytochemicals as feasible candidates for future neurotherapeutics.

Saffron extract attenuates Sofosbuvir-induced retinal neurodegeneration in albino rat

Sofosbuvir is a novel drug candidate for the treatment of hepatitis C viral infection; however, vision loss is one of its growing adverse effects. Saffron is a natural biomolecule with a high antioxidant potential that has been efficiently used in some diseases caused by oxidative stress. This study evaluated Sofosbuvir's neurodegenerative effect on the retina of albino rat and examined the potential protective role of saffron aqueous extract. Twenty-one adult male albino rats were randomly divided into three groups: Control, Sofosbuvir-treated (41.1 mg/kg /day for 6 weeks), and Sofosbuvir + Saffron co-treated groups. Retinal specimens were biochemically analyzed for malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) levels. In addition, light and transmission electron microscopic examination, as well as immunohistochemical staining for Caspase-3, COX-2, and GFAP were performed. Sofosbuvir treatment caused a significant increase in retinal MDA, IL-6, and TNF-α levels coupling with a significant decrease in retinal total antioxidant capacity level. Histopathological findings revealed disturbed retinal architecture, detached pigment epithelium, vacuolated photoreceptors, in addition to a significant decrease in the thicknesses of both outer and inner nuclear layers, and the number of ganglionic cells. Ultrastructural examination revealed extensive degenerative changes in all retinal layers. Caspase-3, COX-2, and GFAP immunohistochemical expressions were significantly increased. Meanwhile, concomitant treatment with Saffron significantly improved retinal redox status, inflammation, histological, and ultrastructural parameters. Saffron may protect the retina from the hazardous effects of Sofosbuvir. Saffron could be used as an adjuvant therapy to protect patients receiving Sofosbuvir from retinal damage.

Critical Review on Nutritional, Bioactive, and Medicinal Potential of Spices and Herbs and Their Application in Food Fortification and Nanotechnology

Medicinal or herbal spices are grown in tropical moist evergreen forestland, surrounding most of the tropical and subtropical regions of Eastern Himalayas in India (Sikkim, Darjeeling regions), Bhutan, Nepal, Pakistan, Iran, Afghanistan, a few Central Asian countries, Middle East, USA, Europe, South East Asia, Japan, Malaysia, and Indonesia. According to the cultivation region surrounded, economic value, and vogue, these spices can be classified into major, minor, and colored tropical spices. In total, 24 tropical spices and herbs (cardamom, black jeera, fennel, poppy, coriander, fenugreek, bay leaves, clove, chili, cassia bark, black pepper, nutmeg, black mustard, turmeric, saffron, star anise, onion, dill, asafoetida, celery, allspice, kokum, greater galangal, and sweet flag) are described in this review. These spices show many pharmacological activities like anti-inflammatory, antimicrobial, anti-diabetic, anti-obesity, cardiovascular, gastrointestinal, central nervous system, and antioxidant activities. Numerous bioactive compounds are present in these selected spices, such as 1,8-cineole, monoterpene hydrocarbons, γ-terpinene, cuminaldehyde, trans-anethole, fenchone, estragole, benzylisoquinoline alkaloids, eugenol, cinnamaldehyde, piperine, linalool, malabaricone C, safrole, myristicin, elemicin, sinigrin, curcumin, bidemethoxycurcumin, dimethoxycurcumin, crocin, picrocrocin, quercetin, quercetin 4'-O-β-glucoside, apiol, carvone, limonene, α-phellandrene, galactomannan, rosmarinic acid, limonene, capsaicinoids, eugenol, garcinol, and α-asarone. Other than that, various spices are used to synthesize different types of metal-based and polymer-based nanoparticles like zinc oxide, gold, silver, selenium, silica, and chitosan nanoparticles which provide beneficial health effects such as antioxidant, anti-carcinogenic, anti-diabetic, enzyme retardation effect, and antimicrobial activity. The nanoparticles can also be used in environmental pollution management like dye decolorization and in chemical industries to enhance the rate of reaction by the use of catalytic activity of the nanoparticles. The nutritional value, phytochemical properties, health advantages, and both traditional and modern applications of these spices, along with their functions in food fortification, have been thoroughly discussed in this review.

Efficacy and safety of dietary polyphenols in rheumatoid arthritis: A systematic review and meta-analysis of 47 randomized controlled trials

OBJECTIVE

To evaluate safety and efficacy of dietary polyphenols in the treatment of rheumatoid arthritis (RA).

METHODS

CNKI, Pubmed, Cochrane library, Embase were searched to collect randomized controlled trials (RCTs) of dietary polyphenols in the treatment of RA. The databases were searched from the time of their establishment to November 8nd, 2022. After 2 reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies, Meta-analysis was performed using RevMan5.4 software.

RESULTS

A total of 49 records (47 RCTs) were finally included, involving 3852 participants and 15 types of dietary polyphenols (Cinnamon extract, Cranberry extract, Crocus sativus L. extract, Curcumin, Garlic extract, Ginger extract, Hesperidin, Olive oil, Pomegranate extract, Puerarin, Quercetin, Resveratrol, Sesamin, Tea polyphenols, Total glucosides of paeony). Pomegranate extract, Resveratrol, Garlic extract, Puerarin, Hesperidin, Ginger extract, Cinnamon extract, Sesamin only involve in 1 RCT. Cranberry extract, Crocus sativus L. extract, Olive oil, Quercetin, Tea polyphenols involve in 2 RCTs. Total glucosides of paeony and Curcumin involve in more than 3 RCTs. These RCTs showed that these dietary polyphenols could improve disease activity score for 28 joints (DAS28), inflammation levels or oxidative stress levels in RA. The addition of dietary polyphenols did not increase adverse events.

CONCLUSION

Dietary polyphenols may improve DAS28, reduce C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and improve oxidative stress, etc. However, more RCTs are needed to verify or modify the efficacy and safety of dietary polyphenols.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022315645.

Therapeutic approaches of nutraceuticals in the prevention of Alzheimer's disease

Alzheimer's disease (AD) is a neurological illness that causes memory loss over time. Currently, available pharmaceutical medicines and products are limited, and they have side effects at a higher price. Researchers and scientists have observed significant effects of nutraceuticals. Various preclinical and clinical studies were investigated for the Anti-Alzheimer's activity of nutraceuticals. The increasing ability of the pathogenesis of AD has led to the analysis of novel therapeutic targets, including the pathophysiological mechanisms and distinct cascades. So, current improvement will show the most adequate and prominent nutraceuticals and suggested concise mechanisms involving autophagy regulation, anti-inflammatory, antioxidant, mitochondrial homeostasis, and others. The effects of nutraceuticals cannot be ignored; it is important to investigate high-quality clinical trials. Given the potential of nutraceuticals to battle AD as multi-targeted therapies, it's vital to evaluate them as viable lead compounds for drug discovery and development. To the best of the authors 'knowledge, modification of blood-brain barrier permeability, bioavailability, and aspects of randomized clinical trials should be considered in prospective investigations. PRACTICAL APPLICATIONS: Advancements in molecular diagnostic and fundamentals have implemented particular usefulness for drug evaluation. An excess of experimental knowledge occurs regarding the effect of nutraceuticals on AD. There are various preclinical and clinical studies that have been done on nutraceuticals. In addition, various substitute inhibit and enhance some pathophysiological levels associated with AD. Nutraceuticals are easily available and have fewer side effects with cost-effective advantages. However, further investigations and clinical trials are required to encourage its effect on disease.

Antioxidants affect endoplasmic reticulum stress-related diseases

The endoplasmic reticulum (ER) is a complex multifunctional organelle that maintains cell homeostasis. Intrinsic and extrinsic factors alter ER functions, including the rate of protein folding that triggers the accumulation of misfolded proteins and alters homeostasis, thus generating stress in the ER, which activates the unfolded protein response (UPR) pathway to promote cell survival and restore their homeostasis; however, if the damage is not corrected, it could also trigger cell death. In addition, ER stress and oxidative stress are closely related because excessive production of reactive oxygen species (ROS), a well-known inducer of ER stress, promotes the accumulation of misfolded proteins; at the same time, the ER stress enhances ROS production, generating a pathological cycle. Furthermore, it has been described that the dysregulation of the UPR contributes to the progression of various diseases, so the use of compounds capable of regulating ER stress, such as antioxidants, has been used in several experimental models of diseases to alleviate the damage induced by the maladaptive signaling of the UPR, the mechanism of action of antioxidants generally is dose-dependent, and it is specific in each tissue and pathology, could decrease or enhance specific proteins of the UPR to have beneficial or detrimental effects.

Reactive oxygen species-responsive nanodrug of natural crocin-i with prolonged circulation for effective radioprotection

With the progress of nuclear technology including radiotherapy and radiodiagnosis, radiation has been widely used in many fields as a powerful diagnostic and therapeutic tool in the medical area. Unfortunately, acute radiation disease will occur if the human body is accidentally exposed to a large dosage of ionizing radiation. However, clinical radioprotective agents are being challenged by the short half-life and several side effects. In this work, a reactive oxygen species-responsive nanodrug is developed for efficient radioprotection. The nanodrug was prepared by modifying Crocin-I with 4-pentylphenylboronic acid (PBA) and exhibited effective responsiveness and scavenging activity of reactive oxygen species. PBA-Crocin nanodrug displayed good biocompatibility and radioprotection effect compared to Crocin-I in vitro. The survival rate of cells treated with PBA-Crocin (10 μg mL^-1) is comparable to that treated with amifostine (12.5 μg mL^-1, the only radioprotector approved by the United States Food and Drug Administration clinically) after 6 Gy irradiation. Importantly, PBA-Crocin resulted in markedly prevention of radiation-induced damage in peripheral blood cells and a 1.6-fold longer retention time of Crocin-I in plasma in comparison with Crocin-I. The finding suggests a new design for natural medicine in effective radioprotection.

Protective Effect of Crocin on Immune Checkpoint Inhibitors-Related Myocarditis Through Inhibiting NLRP3 Mediated Pyroptosis in Cardiomyocytes via NF-κB Pathway

Purpose

Immune checkpoint inhibitors (ICIs)-related myocarditis is now one of the most critical immune-related adverse effects (irAEs) in tumor immunotherapy, which has raised great concern in cardio-oncology. The pathogenesis involved in cardiac injury remains elusive. Crocin, the main component of saffron, has shown distinct functions in cardioprotective and anti-inflammation properties. We therefore aimed to investigate the potential effect of crocin on the protection of ICIs-related myocarditis and its underlying molecular mechanism.

Methods

We immunized the BALB/c mice with murine cardiac troponin I (cTnI) peptide and additionally gave anti-mouse programmed death 1 (PD-1) to induce the mouse model of ICIs-related myocarditis. Mice were treated with crocin at different dosages. In vitro, HL-1 cells were pre-incubated with crocin at different concentrations and then stimulated with lipopolysaccharide (LPS). Myocardial contractile functions, myocardial inflammation and fibrosis, and myocardial injury were assessed. The expressions of pyroptosis-related proteins and nuclear factor-κB (NF-κB) pathway were evaluated.

Results

Crocin treatment could partially reverse the ICIs-related myocarditis in terms of improving heart function, ameliorating inflammation and fibrosis in the myocardium, and alleviating myocardial injury. Mechanistically, ICIs administration significantly activated pyrin domain-containing protein 3 (NLRP3) inflammasome in cardiomyocytes. Crocin treatments significantly downregulated the expression of NLRP3, cleaved gasdermin D (GSDMD), cleaved caspase1, interleukin-1β (IL-1β), and IL-18. Besides, crocin inhibited the activation of NF-κB pathway, which performed as reducing the phosphorylation of p-NF-kappa-B inhibitor-α (p-IκBα), degradation of IκBα, phosphorylation of p65 and p65 DNA binding activity both in vivo and in vitro.

Conclusion

By reversing the pyroptosis in cardiomyocytes, crocin treatment in a mouse model exerted great potential to aid in the prevention of ICIs-related myocarditis from a novel target.

Medicine-Food Herbs against Alzheimer’s Disease: A Review of Their Traditional Functional Features, Substance Basis, Clinical Practices and Mechanisms of Action

Alzheimer’s disease (AD) is a progressive, neurodegenerative disorder that currently has reached epidemic proportions among elderly populations around the world. In China, available traditional Chinese medicines (TCMs) that organically combine functional foods with medicinal values are named “Medicine Food Homology (MFH)”. In this review, we focused on MFH varieties for their traditional functional features, substance bases, clinical uses, and mechanisms of action (MOAs) for AD prevention and treatment. We consider the antiAD active constituents from MFH species, their effects on in vitro/in vivo AD models, and their drug targets and signal pathways by summing up the literature via a systematic electronic search (SciFinder, PubMed, and Web of Science). In this paper, several MFH plant sources are discussed in detail from in vitro/in vivo models and methods, to MOAs. We found that most of the MFH varieties exert neuroprotective effects and ameliorate cognitive impairments by inhibiting neuropathological signs (Aβ-induced toxicity, amyloid precursor protein, and phosphorylated Tau immunoreactivity), including anti-inflammation, antioxidative stress, antiautophagy, and antiapoptosis, etc. Indeed, some MFH substances and their related phytochemicals have a broad spectrum of activities, so they are superior to simple single-target drugs in treating chronic diseases. This review can provide significant guidance for people’s healthy lifestyles and drug development for AD prevention and treatment.

The Effects of Crocin on Bone and Cartilage Diseases

Crocin, the main biologically active carotenoid of saffron, generally is derived from the dried trifid stigma of Crocus sativus L. Many studies have demonstrated that crocin has several therapeutic effects on biological systems through its anti-oxidant and anti-inflammatory properties. The wide range of crocin activities is believed to be because of its ability to anchor to many proteins, triggering some cellular pathways responsible for cell proliferation and differentiation. It also has therapeutic potentials in arthritis, osteoarthritis, rheumatoid arthritis, and articular pain probably due to its anti-inflammatory properties. Anti-apoptotic effects, as well as osteoclast inhibition effects of crocin, have suggested it as a natural substance to treat osteoporosis and degenerative disease of bone and cartilage. Different mechanisms underlying crocin effects on bone and cartilage repair have been investigated, but remain to be fully elucidated. The present review aims to undertake current knowledge on the effects of crocin on bone and cartilage degenerative diseases with an emphasis on its proliferative and differentiative properties in mesenchymal stem cells.

Leu27 IGF-II-induced hypertrophy in H9c2 cardiomyoblasts is ameliorated by saffron by regulation of calcineurin/NFAT and CaMKIIδ signaling

The insulin-like growth factor II receptor (IGF-IIR) induces myocardial hypertrophy under various pathological conditions like diabetes and hypertension via G protein receptors like Gαq or Gαs. Increased expression of the ligand IGF II and IGF-IIR induces pathological hypertrophy through downstream signaling mediators such as calcineurin, nuclear factor of activated T cells 3 and calcium-calmodulin (CaM)-dependent kinase II (CaMKII)-histone deacetylase 4 (HDAC4). The dried stigma of Crocus sativus L. (saffron) has a long repute as a traditional medicine against various disorders. In the present study, we have investigated whether C. sativus extract (CSE) canameliorate Leu²⁷ IGF-II triggered hypertrophy and have elucidated the underlying mechanism of protection. Additionally, the effects of oleic acid (OA), an activator of calcineurin and CaMKII was investigated thereof. The results demonstrate that CSE can ameliorate Leu²⁷ IGF-II-induced hypertrophy seemingly through regulation of calcineurin-NFAT3 and CaMKII-HDAC4 signaling cascade.

Targeting Mitochondria by Plant Secondary Metabolites: A Promising Strategy in Combating Parkinson's Disease

Parkinson’s disease (PD) is one of the most prevalent and debilitating neurodegenerative conditions, and is currently on the rise. Several dysregulated pathways are behind the pathogenesis of PD; however, the critical targets remain unclear. Accordingly, there is an urgent need to reveal the key dysregulated pathways in PD. Prevailing reports have highlighted the importance of mitochondrial and cross-talked mediators in neurological disorders, genetic changes, and related complications of PD. Multiple pathophysiological mechanisms of PD, as well as the low efficacy and side effects of conventional neuroprotective therapies, drive the need for finding novel alternative agents. Recently, much attention has been paid to using plant secondary metabolites (e.g., flavonoids/phenolic compounds, alkaloids, and terpenoids) in the modulation of PD-associated manifestations by targeting mitochondria. In this line, plant secondary metabolites have shown promising potential for the simultaneous modulation of mitochondrial apoptosis and reactive oxygen species. This review aimed to address mitochondria and multiple dysregulated pathways in PD by plant-derived secondary metabolites.

The Role of Microglia in the Development of Neurodegenerative Diseases

Microglia play an important role in the maintenance and neuroprotection of the central nervous system (CNS) by removing pathogens, damaged neurons, and plaques. Recent observations emphasize that the promotion and development of neurodegenerative diseases (NDs) are closely related to microglial activation. In this review, we summarize the contribution of microglial activation and its associated mechanisms in NDs, such as epilepsy, Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD), based on recent observations. This review also briefly introduces experimental animal models of epilepsy, AD, PD, and HD. Thus, this review provides a better understanding of microglial functions in the development of NDs, suggesting that microglial targeting could be an effective therapeutic strategy for these diseases.

Protective effects of crocin against endogenous Aβ-induced neurotoxicity in N2a/APP695swe cells

Alzheimer's disease (AD) is a most common neurodegenerative disorder worldwide. Because of its complex pathogenesis, the prevention and therapies of AD still are a severe challenge. Evidence suggested that crocin, the major component of saffron, exhibited neuroprotective effects in AD. As such, in this study, N2a/APP695swe cells were enrolled to investigate the effects of crocin on endogenous Aβ-induced neurotoxicity. Crocin (100 and 200 μM) could ameliorate cytotoxicity according to CCK-8 assay and reduce apoptosis in line with Hoechst 33,342 staining and Annexin V-FITC/PI double staining in N2a/APP695swe cells. Reduced ROS generation and elevated MMP were found in N2a/APP695swe cells treated with crocin (100 and 200 μM). Additionally, crocin at concentrations of 100 and 200 μM inhibited the release of cytochrome and attenuated caspases-3 activity in N2a/APP695swe cells. Furthermore, succinylation, crotonylation, 2-hydroxyisobutyrylation, malonylation, and phosphorylation were significantly reduced, while a slight increase of acetylation was found in 100-μM crocin treated N2a/APP695swe cells. Taken together, crocin may be a promising natural product candidate for the effective cure of AD.

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.

Saffron extract attenuates neuroinflammation in rmTBI mouse model by suppressing NLRP3 inflammasome activation via SIRT1

Traumatic brain injury (TBI) remains a major cause of morbidity and disability worldwide and a healthcare burden. TBI is an important risk factor for neurodegenerative diseases hallmarked by exacerbated neuroinflammation. Neuroinflammation in the cerebral cortex plays a critical role in secondary injury progression following TBI. The NOD-like receptors (NLR) family pyrin domain containing 3 (NLRP3) inflammasome is a key player in initiating the inflammatory response in various central nervous system disorders entailing TBI. This current study aims to investigate the role of NLRP3 in repetitive mild traumatic brain injury (rmTBI) and identify the potential neuroprotective effect of saffron extract in regulating the NLRP3 inflammasome. 24 hours following the final injury, rmTBI causes an upregulation in mRNA levels of NLRP3, caspase-1, the apoptosis-associated speck-like protein containing a CARD (ASC), nuclear factor kappa B (NF-κB), interleukin-1Beta (IL-1β), interleukin 18 (IL-18), nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase 1 (HMOX1). Protein levels of NLRP3, sirtuin 1 (SIRT1), glial fibrillary acidic protein (GFAP), ionized calcium-binding adaptor molecule 1 (Iba1), and neuronal nuclei (Neu N) also increased after rmTBI. Administration of saffron alleviated the degree of TBI, as evidenced by reducing the neuronal damage, astrocyte, and microglial activation. Pretreatment with saffron inhibited the activation of NLRP3, caspase-1, and ASC concurrent to reduced production of the inflammatory cytokines IL-1β and IL-18. Additionally, saffron extract enhanced SIRT1 expression, NRF2, and HMOX1 upregulation. These results suggest that NLRP3 inflammasome activation and the subsequent inflammatory response in the mice cortex are involved in the process of rmTBI. Saffron blocked the inflammatory response and relieved TBI by activating detoxifying genes and inhibiting NLRP3 activation. The effect of saffron on the NLRP3 inflammasome may be SIRT1 and NF-κB dependent in the rmTBI model. Thus, brain injury biomarkers will help in identifying a potential therapeutic target in treating TBI-induced neurodegenerative diseases.

An Epidemiological Study Report on the Antioxidant and Phenolic Content of Selected Mediterranean Functional Foods, Their Consumption Association with the Body Mass Index, and Consumers Purchasing Behavior in a Sample of Healthy Greek Adults

Functional food consumption is shown to have a positive effect on anthropometric parameters and human health promotion. In addition, consumers seem to be more interested in food choices, that may have a positive effect on their health. The current study aimed to identify the antioxidant and phenolic content of naturally functional foods from the Mediterranean diet and to investigate consumer behavior towards their consumption in terms of their weight control, as well as their purchasing behavior and knowledge of functional foods. For this purpose, blueberries, cranberries, pomegranate, grapefruit, red peppers, almonds and mountain tea were analyzed for their phenolic content and antioxidant capacity, using the Folin-Ciocalteau and Ferric Reducing Antioxidant Power assays, respectively. Furthermore, nine hundred forty-nine healthy Greek adults participated in an epidemiological study, by completing a validated food frequency questionnaire, for the consumption of the above investigated functional foods. Five hundred and fifty participants also completed an online questionnaire investigating factors that consumers evaluate when purchasing functional foods. Study results showed that the analyzed functional foods were high in antioxidants and phenolic compounds, especially the mountain tea. The increased consumption of cranberries, pomegranate, grapefruit, red peppers and mountain tea was significantly correlated with a decreased Body Mass Index, suggesting a possible positive role, in weight control. Participants seemed to be aware of the beneficial role of these specific investigated Mediterranean functional foods to human health. They evaluated the price, taste and nutritional value, as critical factors to buy these food products. A combination of factors seems to lead them to purchase and consume these functional foods. Future epidemiological and clinical studies should be conducted in order to further evaluate consumer preferences and bioactivity mechanisms related to Mediterranean functional food consumption.

1H-NMR Metabolic Profiling and Antioxidant Activity of Saffron (Crocus sativus) Cultivated in Lebanon

Despite the beneficial health properties shown by Lebanese saffron, its qualitative and quantitative composition has never been investigated before. In the present study, NMR spectroscopy, together with antioxidant activity assays, were applied to evaluate the chemical composition of saffron samples of different geographical origins (Lebanon, Italy, Iran, and India) and to categorize the Lebanese saffron for the first time. The distinction between Lebanese saffron and that produced in other countries was attributed to its higher linolenic and linoleic fatty acids, glucose and picrocrocin contents. Moreover, spices produced in three different regions of the Lebanese territory have been clearly differentiated. Saffron cultivated in the Qaa region displayed a high glucose, fatty acids and polyphenols content, whereas Hermel saffron exhibited the largest rate of picrocrocin and glycosylated carotenoids. Finally, samples from Baalbeck showed lower rates for the majority of metabolites. Moreover, Lebanese saffron showed a high antioxidant activity in ABTS and DPPH assays. A low dose of saffron extract (10 µg/mL) inhibited the growth of human lung adenocarcinoma cells, probably due to the high polyphenolic content. This study highlights the quality and peculiarity of Lebanese saffron cultivated in Northern Beqaa district and allows for a good discrimination between spices produced in relatively close territory.

Potentials of autophagy enhancing natural products in the treatment of Parkinson disease

Parkinson disease (PD) is a progressive neurodegenerative movement disorder characterized by motor and non-motor symptoms due to loss of striatal dopaminergic neurons and disruption of degradation signaling leading to the formation of Lewy bodies (aggregation of α-synuclein). Presently, there are no disease modifying therapy for PD despite improvement in the understanding of the disease pathogenesis. However, the drugs currently used in PD management provide symptomatic relieve for motor symptoms without significant improvement in non-motor complications, thus, a public health burden on caregivers and healthcare systems. There is therefore the need to discover disease modifying therapy with strong potential to halt the disease progression. Recent trend has shown that the dysfunction of lysosomal-autophagy pathway is highly implicated in PD pathology, hence, making autophagy a key player owing to its involvement in degradation and clearance of misfolded α-synuclein (a major hallmark in PD pathology). In this review, we described the current drugs/strategy in the management of PD including targeting the autophagy pathway as a novel approach that could serve as potential intervention for PD management. The discovery of small molecules or natural products capable of enhancing autophagy mechanism could be a promising strategy for PD treatment.

Potentials of autophagy enhancing natural products in the treatment of Parkinson disease

Parkinson disease (PD) is a progressive neurodegenerative movement disorder characterized by motor and non-motor symptoms due to loss of striatal dopaminergic neurons and disruption of degradation signaling leading to the formation of Lewy bodies (aggregation of α-synuclein). Presently, there are no disease modifying therapy for PD despite improvement in the understanding of the disease pathogenesis. However, the drugs currently used in PD management provide symptomatic relieve for motor symptoms without significant improvement in non-motor complications, thus, a public health burden on caregivers and healthcare systems. There is therefore the need to discover disease modifying therapy with strong potential to halt the disease progression. Recent trend has shown that the dysfunction of lysosomal-autophagy pathway is highly implicated in PD pathology, hence, making autophagy a key player owing to its involvement in degradation and clearance of misfolded α-synuclein (a major hallmark in PD pathology). In this review, we described the current drugs/strategy in the management of PD including targeting the autophagy pathway as a novel approach that could serve as potential intervention for PD management. The discovery of small molecules or natural products capable of enhancing autophagy mechanism could be a promising strategy for PD treatment.

An Overview of Stroke: Mechanism, In vivo Experimental Models Thereof, and Neuroprotective Agents

BACKGROUND

Stroke is one of the causes of death and disability globally. Brain attack is because of the acute presentation of stroke, which highlights the requirement for decisive action to treat it.

OBJECTIVE

The mechanism and in-vivo experimental models of stroke with various neuroprotective agents are highlighted in this review.

METHOD

The damaging mechanisms may proceed by rapid, nonspecific cell lysis (necrosis) or by the active form of cell death (apoptosis or necroptosis), depending upon the duration and severity and of the ischemic insult.

RESULTS

Identification of injury mediators and pathways in a variety of experimental animal models of global cerebral ischemia has directed to explore the target-specific cytoprotective strategies, which are critical to clinical brain injury outcomes.

CONCLUSION

The injury mechanism, available encouraging medicaments thereof, and outcomes of natural and modern medicines for ischemia have been summarized. In spite of available therapeutic agents (thrombolytics, calcium channel blockers, NMDA receptor antagonists and antioxidants), there is a need for an ideal drug for strokes.

Nutraceuticals-based therapeutic approach: recent advances to combat pathogenesis of Alzheimer's disease

Introduction: Alzheimer's disease (AD) is a progressive neurodegenerative disease accompanying memory deficits. The available pharmaceutical care has some limitations mostly entailing side effects, shelf-life, and patient's compliance. The momentous implications of nutraceuticals in AD have attracted scientists. Several preclinical studies for the investigation of nutraceuticals have been conducted.Areas covered: This review focuses on the potential use of a nutraceuticals-based therapeutic approach to treat and prevent AD. Increasing knowledge of AD pathogenesis has led to the discovery of new therapeutic targets including pathophysiological mechanisms and various cascades. Hence, the present contribution will attend to the most popular and effective nutraceuticals with proposed brief mechanisms entailing antioxidant, anti-inflammatory, autophagy regulation, mitochondrial homeostasis, and more. Therefore, even though the effectiveness of nutraceuticals cannot be dismissed, it is essential to do further high-quality randomized clinical trials.Expert opinion: According to the potential of nutraceuticals to combat AD as multi-target directed drugs, there is critical importance to assess them as feasible lead compounds for drug discovery and development. To the best of the authors' knowledge, modification of blood-brain barrier permeability, bioavailability, and features of randomized clinical trials should be considered in prospective studies.

Crocetin and related oxygen diffusion-enhancing compounds: Review of chemical synthesis, pharmacology, clinical development, and novel therapeutic applications

The current pandemic forced us to introspect and revisit our armamentarium of medicinal agents which could be life‐saving in emergency situations. Oxygen diffusion‐enhancing compounds represent one such class of potential therapeutic agents, particularly in ischemic conditions. As rewarding as the name suggests, these agents, represented by the most advanced and first‐in‐class molecule, trans‐sodium crocetinate (TSC), are the subject of intense clinical investigation, including Phase 1b/2b clinical trials for COVID‐19. Being a successor of a natural product, crocetin, TSC is being investigated for various cancers as a radiosensitizer owing to its oxygen diffusion enhancement capability. The unique properties of TSC make it a promising therapeutic agent for various ailments such as hemorrhagic shock, stroke, heart attack, among others. The present review outlines various (bio)synthetic strategies, pharmacological aspects, clinical overview and potential therapeutic benefits of crocetin and related compounds including TSC. The recent literature focusing on the delivery aspects of these compounds is covered as well to paint the complete picture to the curious reader. Given the potential TSC holds as a first‐in‐class agent, small‐ and/or macromolecular therapeutics based on the core concept of improved oxygen diffusion from blood to the surrounding tissues where it is needed the most, will be developed in future and satisfy the unmet medical need for many diseases and disorders.

Molecular Mechanisms of Astaxanthin as a Potential Neurotherapeutic Agent

Neurological disorders are diseases of the central and peripheral nervous system that affect millions of people, and the numbers are rising gradually. In the pathogenesis of neurodegenerative diseases, the roles of many signaling pathways were elucidated; however, the exact pathophysiology of neurological disorders and possible effective therapeutics have not yet been precisely identified. This necessitates developing multi-target treatments, which would simultaneously modulate neuroinflammation, apoptosis, and oxidative stress. The present review aims to explore the potential therapeutic use of astaxanthin (ASX) in neurological and neuroinflammatory diseases. ASX, a member of the xanthophyll group, was found to be a promising therapeutic anti-inflammatory agent for many neurological disorders, including cerebral ischemia, Parkinson's disease, Alzheimer's disease, autism, and neuropathic pain. An effective drug delivery system of ASX should be developed and further tested by appropriate clinical trials.

Bioanalytical Method Development and Validation Study of Neuroprotective Extract of Kashmiri Saffron Using Ultra-Fast Liquid Chromatography-Tandem Mass Spectrometry (UFLC-MS/MS): In Vivo Pharmacokinetics of Apocarotenoids and Carotenoids

Kashmir saffron (Crocus sativus L.), also known as Indian saffron, is an important Asian medicinal plant with protective therapeutic applications in brain health. The main bioactive in Kashmir or Indian Saffron (KCS) and its extract (CSE) are apocarotenoids picrocrocin (PIC) and safranal (SAF) with carotenoids, crocetin esters (crocins), and crocetins. The ultra-fast liquid chromatography(UFLC)- photodiode array standardization confirmed the presence of biomarkers PIC, trans-4-GG-crocin (T4C), trans-3-Gg-crocin (T3C), cis-4-GG-crocin (C4C), trans-2-gg-crocin (T2C), trans-crocetin (TCT), and SAF in CSE. This study’s objectives were to develop and validate a sensitive and rapid UFLC-tandem mass spectrometry method for PIC and SAF along T4C and TCT in rat plasma with internal standards (IS). The calibration curves were linear (R² > 0.990), with the lower limit of quantification (LLOQ) as 10 ng/mL. The UFLC-MS/MS assay-based precision (RSD, <15%) and accuracy (RE, −11.03–9.96) on analytical quality control (QC) levels were well within the acceptance criteria with excellent recoveries (91.18–106.86%) in plasma samples. The method was applied to investigate the in vivo pharmacokinetic parameters after oral administration of 40 mg/kg CSE in the rats (n = 6). The active metabolite TCT and T4C, PIC, SAF were quantified for the first time with T3C, C4C, T2C by this validated bioanalytical method, which will be useful for preclinical/clinical trials of CSE as a potential neuroprotective dietary supplement.

Liposomes: Novel Drug Delivery Approach for Targeting Parkinson's Disease

Parkinson's disease is one of the most severe progressive neurodegenerative disorders, having a mortifying effect on the health of millions of people around the globe. The neural cells producing dopamine in the substantia nigra of the brain die out. This leads to symptoms like hypokinesia, rigidity, bradykinesia, and rest tremor. Parkinsonism cannot be cured, but the symptoms can be reduced with the intervention of medicinal drugs, surgical treatments, and physical therapies. Delivering drugs to the brain for treating Parkinson's disease is very challenging. The blood-brain barrier acts as a highly selective semi-permeable barrier, which refrains the drug from reaching the brain. Conventional drug delivery systems used for Parkinson's disease do not readily cross the blood barrier and further lead to several side-effects. Recent advancements in drug delivery technologies have facilitated drug delivery to the brain without flooding the bloodstream and by directly targeting the neurons. In the era of Nanotherapeutics, liposomes are an efficient drug delivery option for brain targeting. Liposomes facilitate the passage of drugs across the blood-brain barrier, enhances the efficacy of the drugs, and minimize the side effects related to it. The review aims at providing a broad updated view of the liposomes, which can be used for targeting Parkinson's disease.

Fucoxanthin Prevents 6-OHDA-Induced Neurotoxicity by Targeting Keap1

As the most abundant marine carotenoid extracted from seaweeds, fucoxanthin (FUC) is considered to have excellent neuroprotective activity. However, the target of FUC for its neuroprotective properties remains largely unclear. Oxidative stress is one of the initiating factors causing neuronal cell loss and necrosis, and it is also an important inducement of Parkinson's disease (PD). In the present study, the neuroprotective effect of FUC was assessed using a 6-hydroxydopamine- (6-OHDA-) induced neurotoxicity model. FUC suppressed 6-OHDA-induced accumulation of intracellular ROS, the disruption of mitochondrial membrane potential, and cell apoptosis through the Nrf2-ARE pathway. Keap1 as a repressor of Nrf2 can regulate the activity of Nrf2. Here, the biolayer interferometry (BLI) assay demonstrated that FUC specifically targeted Keap1 and inhibited the interaction between Keap1 and Nrf2. FUC bound to the hydrophobic region of Keap1 pocket and formed hydrogen bonding interactions with Arg⁴¹⁵ and Tyr⁵²⁵. Besides, it also dose-dependently upregulated the expressions of antioxidant enzymes, such as nicotinamide heme oxygenase-1, glutamate-cysteine ligase modifier subunit, and glutamate-cysteine ligase catalytic subunit, in 6-OHDA-induced PC12 cells. In 6-OHDA-exposed zebrafish, FUC pretreatment significantly increased the total swimming distance of zebrafish larvae and improved the granular region of the brain tissue damage. These results suggested that FUC could protect the neuronal cells against 6-OHDA-induced injury via targeting Keap1.

PLGA Multiplex Membrane Platform for Disease Modelling and Testing of Therapeutic Compounds

A proper validation of an engineered brain microenvironment requires a trade of between the complexity of a cellular construct within the in vitro platform and the simple implementation of the investigational tool. The present work aims to accomplish this challenging balance by setting up an innovative membrane platform that represents a good compromise between a proper mimicked brain tissue analogue combined with an easily accessible and implemented membrane system. Another key aspect of the in vitro modelling disease is the identification of a precise phenotypic onset as a definite hallmark of the pathology that needs to be recapitulated within the implemented membrane system. On the basis of these assumptions, we propose a multiplex membrane system in which the recapitulation of specific neuro-pathological onsets related to Alzheimer’s disease pathologies, namely oxidative stress and β-amyloid_1–42 toxicity, allowed us to test the neuroprotective effects of trans-crocetin on damaged neurons. The proposed multiplex membrane platform is therefore quite a versatile tool that allows the integration of neuronal pathological events in combination with the testing of new molecules. The present paper explores the use of this alternative methodology, which, relying on membrane technology approach, allows us to study the basic physiological and pathological behaviour of differentiated neuronal cells, as well as their changing behaviour, in response to new potential therapeutic treatment.

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.

Crocins from Crocus sativus L. in the Management of Hyperglycemia. In Vivo Evidence from Zebrafish

Diabetes mellitus is a disease characterized by persistent high blood glucose levels and accompanied by impaired metabolic pathways. In this study, we used zebrafish to investigate the effect of crocins isolated from Crocus sativus L., on the control of glucose levels and pancreatic β-cells. Embryos were exposed to an aqueous solution of crocins and whole embryo glucose levels were measured at 48 h post-treatment. We showed that the application of crocins reduces zebrafish embryo glucose levels and enhances insulin expression. We also examined whether crocins are implicated in the metabolic pathway of gluconeogenesis. We showed that following a single application of crocins and glucose level reduction, the expression of phosphoenolpyruvate carboxykinase1 (pck1), a key gene involved in glucose metabolism, is increased. We propose a putative role for the crocins in glucose metabolism and insulin management.

Delivering Crocetin across the Blood-Brain Barrier by Using γ-Cyclodextrin to Treat Alzheimer's Disease

Crocetin (CRT) has shown various neuroprotective effects such as antioxidant activities and the inhibition of amyloid β fibril formation, and thus is a potential therapeutic candidate for Alzheimer's disease (AD). However, poor water solubility and bioavailability are the major obstacles in formulation development and pharmaceutical applications of CRT. In this study, a novel water-soluble CRT-γ-cyclodextrin inclusion complex suitable for intravenous injection was developed. The inclusion complex was nontoxic to normal neuroblastoma cells (N2a cells and SH-SY5Y cells) and AD model cells (7PA2 cells). Furthermore, it showed stronger ability to downregulate the expression of C-terminus fragments and level of amyloid β in 7PA2 cell line as compared to the CRT free drug. Both inclusion complex and CRT were able to prevent SH-SY5Y cell death from H2O2-induced toxicity. The pharmacokinetics and biodistribution studies showed that CRT-γ-cyclodextrin inclusion complex significantly increased the bioavailability of CRT and facilitated CRT crossing the blood-brain barrier to enter the brain. This data shows a water-soluble γ-cyclodextrin inclusion complex helped to deliver CRT across the blood-brain barrier. This success should fuel further pharmaceutical research on CRT in the treatment for AD, and it should engender research on γ-cyclodextrin with other drugs that have so far not been explored.

Role of Oxidative Stress and Metal Toxicity in the Progression of Alzheimer's Disease

Alzheimer's disease (AD) is one of the life-threatening neurodegenerative disorders in the elderly (>60 years) and incurable across the globe to date. AD is caused by the involvement of various genetic, environmental and lifestyle factors that affect neuronal cells to degenerate over the period of time. The oxidative stress is engaged in the pathogenesis of various disorders and its key role is also linked to the etiology of AD. AD is attributed by neuronal loss, abnormal accumulation of Amyloid-β (Aβ) and neurofibrillary tangles (NFTs) with severe memory impairments and other cognitive dysfunctions which lead to the loss of synapses and neuronal death and eventual demise of the individual. Increased production of reactive oxygen species (ROS), loss of mitochondrial function, altered metal homeostasis, aberrant accumulation of senile plaque and mitigated antioxidant defense mechanism all are indulged in the progression of AD. In spite of recent advances in biomedical research, the underlying mechanism of disruption of redox balance and the actual source of oxidative stress is still obscure. This review highlights the generation of ROS through different mechanisms, the role of some important metals in the progression of AD and free radical scavenging by endogenous molecule and supplementation of nutrients in AD.