Flavonoids, cognition, and dementia: actions, mechanisms, and potential therapeutic utility for Alzheimer disease

The experimental significance of isorhamnetin as an effective therapeutic option for cancer: A comprehensive analysis

Isorhamnetin (C16H12O7), a 3'-O-methylated derivative of quercetin from the class of flavonoids, is predominantly present in the leaves and fruits of several plants, many of which have traditionally been employed as remedies due to its diverse therapeutic activities. The objective of this in-depth analysis is to concentrate on Isorhamnetin by addressing its molecular insights as an effective anticancer compound and its synergistic activity with other anticancer drugs. The main contributors to Isorhamnetin's anti-malignant activities at the molecular level have been identified as alterations of a variety of signal transduction processes and transcriptional agents. These include ROS-mediated cell cycle arrest and apoptosis, inhibition of mTOR and P13K pathway, suppression of MEK1, PI3K, NF-κB, and Akt/ERK pathways, and inhibition of Hypoxia Inducible Factor (HIF)-1α expression. A significant number of in vitro and in vivo research studies have confirmed that it destroys cancerous cells by arresting cell cycle at the G2/M phase and S-phase, down-regulating COX-2 protein expression, PI3K, Akt, mTOR, MEK1, ERKs, and PI3K signaling pathways, and up-regulating apoptosis-induced genes (Casp3, Casp9, and Apaf1), Bax, Caspase-3, P53 gene expression and mitochondrial-dependent apoptosis pathway. Its ability to suppress malignant cells, evidence of synergistic effects, and design of drugs based on nanomedicine are also well supported to treat cancer patients effectively. Together, our findings establish a crucial foundation for understanding Isorhamnetin's underlying anti-cancer mechanism in cancer cells and reinforce the case for the requirement to assess more exact molecular signaling pathways relating to specific cancer and in vivo anti-cancer activities.

Therapeutic potential of berries in age-related neurological disorders

Aging significantly impacts several age-related neurological problems, such as stroke, brain tumors, oxidative stress, neurodegenerative diseases (Alzheimer's, Parkinson's, and dementia), neuroinflammation, and neurotoxicity. Current treatments for these conditions often come with side effects like hallucinations, dyskinesia, nausea, diarrhea, and gastrointestinal distress. Given the widespread availability and cultural acceptance of natural remedies, research is exploring the potential effectiveness of plants in common medicines. The ancient medical system used many botanical drugs and medicinal plants to treat a wide range of diseases, including age-related neurological problems. According to current clinical investigations, berries improve motor and cognitive functions and protect against age-related neurodegenerative diseases. Additionally, berries may influence signaling pathways critical to neurotransmission, cell survival, inflammation regulation, and neuroplasticity. The abundance of phytochemicals in berries is believed to contribute to these potentially neuroprotective effects. This review aimed to explore the potential benefits of berries as a source of natural neuroprotective agents for age-related neurological disorders.

Effects and safety of resveratrol supplementation in older adults: A comprehensive systematic review

Resveratrol (RSV) has garnered significant attention in recent years due to its potential benefits against chronic diseases. However, its effects and safety in older adults have not been comprehensively studied. This study aimed to determine the effects and safety of RSV supplementation in older adults. MEDLINE/PubMed, Scopus, and Web of Science databases were comprehensively searched for eligible studies. Studies were enrolled if they were randomized clinical trials and had incorporated RSV supplementation for older adults. Two independent authors conducted the literature search, and eligibility was determined according to the PICOS framework. Study details, intervention specifics, and relevant outcomes were collected during the data collection. The Cochrane RoB-2 tool was used to evaluate the risk of bias. This review included 10 studies. The combination of RSV and exercise improved exercise adaptation and muscle function in healthy older adults and physical performance and mobility measures in individuals with functional limitations. RSV showed potential neuroprotective effects in patients with Alzheimer's disease. In overweight individuals, RSV demonstrated a positive impact on cognitive function, but it increased some biomarkers of cardiovascular disease risk at high doses. In older adults with diabetes and those with peripheral artery disease (PAD), RSV was not more effective than placebo. No study reported significant adverse events following RSV treatment. RSV can improve various health parameters in age-related health conditions. However, the optimal dosage, long-term effects, and potential interactions with medications still need to be investigated through well-designed RCTs.

Development of dietary small molecules as multi-targeting treatment strategies for Alzheimer's disease

Cognitive dysfunction can occur both in normal aging and age-related neurological disorders, such as mild cognitive impairment and Alzheimer's disease (AD). These disorders have few treatment options due to side effects and limited efficacy. New approaches to slow cognitive decline are urgently needed. Dietary interventions (nutraceuticals) have received considerable attention because they exhibit strong neuroprotective properties and may help prevent or minimize AD symptoms. Biological aging is driven by a series of interrelated mechanisms, including oxidative stress, neuroinflammation, neuronal apoptosis, and autophagy, which function through various signaling pathways. Recent clinical and preclinical studies have shown that dietary small molecules derived from natural sources, including flavonoids, carotenoids, and polyphenolic acids, can modulate oxidative damage, cognitive impairments, mitochondrial dysfunction, neuroinflammation, neuronal apoptosis, autophagy dysregulation, and gut microbiota dysbiosis. This paper reviews research on different dietary small molecules and their bioactive constituents in the treatment of AD. Additionally, the chemical structure, effective dose, and specific molecular mechanisms of action are comprehensively explored. This paper also discusses the advantages of using nanotechnology-based drug delivery, which significantly enhances oral bioavailability, safety, and therapeutic effect, and lowers the risk of adverse effects. These agents have considerable potential as novel and safe therapeutic agents that can prevent and combat age-related AD.

Therapeutic potential of clinically proven natural products in the management of dementia

Dementia is a common neurodegenerative disorder connected to damage to nerve cells in the brain. Although some conventional drugs are available for dementia treatments and are still sanctified for dementia patients, their short- and long-term side effects and other limitations make treating patients more challenging. The authors aimed to explain novel options for treating dementia with natural products and unravel some clinically proven natural products. This article systematically reviewed recent studies that have investigated the role of natural products and their bioactive compounds for dementia. PubMed Central, Scopus, and Google Scholar databases of articles were collected, and abstracts were reviewed for relevance to the subject matter.In this review, we provide mechanistic insights of clinically validated natural products, including like- Yokukansan, Souvenaid, BDW, Hupergene, Bacopa monnier, Omega-3, Tramiprostate and Palmitoylethanolamide with which have therapeutic efficacy against dementia in the management of dementia. As shown by studies, certain natural ingredients could be used to treat and prevent dementia. We strongly believe that the medicinal plants and phytoconstituents alone or in combination with other compounds would be effective treatments against dementia with lesser side effects as compared to currently available treatments. Moreover, these products should be studied further in order to develop novel dementia medications.

Neurovascular coupling impairment as a mechanism for cognitive deficits in COVID-19

Components that comprise our brain parenchymal and cerebrovascular structures provide a homeostatic environment for proper neuronal function to ensure normal cognition. Cerebral insults (e.g. ischaemia, microbleeds and infection) alter cellular structures and physiologic processes within the neurovascular unit and contribute to cognitive dysfunction. COVID-19 has posed significant complications during acute and convalescent stages in multiple organ systems, including the brain. Cognitive impairment is a prevalent complication in COVID-19 patients, irrespective of severity of acute SARS-CoV-2 infection. Moreover, overwhelming evidence from in vitro, preclinical and clinical studies has reported SARS-CoV-2-induced pathologies in components of the neurovascular unit that are associated with cognitive impairment. Neurovascular unit disruption alters the neurovascular coupling response, a critical mechanism that regulates cerebromicrovascular blood flow to meet the energetic demands of locally active neurons. Normal cognitive processing is achieved through the neurovascular coupling response and involves the coordinated action of brain parenchymal cells (i.e. neurons and glia) and cerebrovascular cell types (i.e. endothelia, smooth muscle cells and pericytes). However, current work on COVID-19-induced cognitive impairment has yet to investigate disruption of neurovascular coupling as a causal factor. Hence, in this review, we aim to describe SARS-CoV-2's effects on the neurovascular unit and how they can impact neurovascular coupling and contribute to cognitive decline in acute and convalescent stages of the disease. Additionally, we explore potential therapeutic interventions to mitigate COVID-19-induced cognitive impairment. Given the great impact of cognitive impairment associated with COVID-19 on both individuals and public health, the necessity for a coordinated effort from fundamental scientific research to clinical application becomes imperative. This integrated endeavour is crucial for mitigating the cognitive deficits induced by COVID-19 and its subsequent burden in this especially vulnerable population.

Impact of micronutrients and nutraceuticals on cognitive function and performance in Alzheimer's disease

Alzheimer's disease (AD) is a major global health problem today and is the most common form of dementia. AD is characterized by the formation of β-amyloid (Aβ) plaques and neurofibrillary clusters, leading to decreased brain acetylcholine levels in the brain. Another mechanism underlying the pathogenesis of AD is the abnormal phosphorylation of tau protein that accumulates at the level of neurofibrillary aggregates, and the areas most affected by this pathological process are usually the cholinergic neurons in cortical, subcortical, and hippocampal areas. These effects result in decreased cognitive function, brain atrophy, and neuronal death. Malnutrition and weight loss are the most frequent manifestations of AD, and these are also associated with greater cognitive decline. Several studies have confirmed that a balanced low-calorie diet and proper nutritional intake may be considered important factors in counteracting or slowing the progression of AD, whereas a high-fat or hypercholesterolemic diet predisposes to an increased risk of developing AD. Especially, fruits, vegetables, antioxidants, vitamins, polyunsaturated fatty acids, and micronutrients supplementation exert positive effects on aging-related changes in the brain due to their antioxidant, anti-inflammatory, and radical scavenging properties. The purpose of this review is to summarize some possible nutritional factors that may contribute to the progression or prevention of AD, understand the role that nutrition plays in the formation of Aβ plaques typical of this neurodegenerative disease, to identify some potential therapeutic strategies that may involve some natural compounds, in delaying the progression of the disease.

The alleviative effects comparison of four flavonoids from bamboo leaves on ulcerative colitis in an Alzheimer mouse model

BACKGROUND

Clinically, patients with dementia are at high risk of developing enteritis, especially those with AD. This study explored the potential therapeutic benefits of bamboo leaf flavonoids (BLF) for ulcerative colitis (UC) treatment in Alzheimer's disease (AD) mouse model.

METHODS

Various methods were employed, including pathological staining of brain/colon tissue, inflammatory cytokine detection in serum, and oxidative stress indicator assessment to compare ulcerative enteritis (UC) injury in normal and AD mice and determine whether AD mice were susceptible to colitis. Then, the effects of BLF on UC and AD were investigated via several unique indices further to determine whether it alleviated colitis injury and possessed beneficial properties. Moreover, four main components of BLF were utilized to treat primary colon epithelial cells and neuron cells to compare their effects in alleviating inflammation and oxidation. Furthermore, homoorientin embedded with ursolic acid was detected by HPLC and the in vitro release simulation experiments of the nanoparticles were performed.

RESULTS

BLF complexes positively impacted ulcerative colitis by reducing disease activity, it also helped to reduce inflammation. Moreover, the BLF complexes decreased oxidative stress in the brain and colon tissues, indicating its potential as a neuroprotective agent. The flavonoid complexes reduced the expression levels of GFAP, Iba-1, and Aβ in the brain tissue, highlighting its role in attenuating neuroinflammation and AD pathology. Additionally, the embedded homoorientin coated with ursolic acid showed stronger bioactivities when compared with the uncoated group.

CONCLUSION

These results suggest that BLF complexes and its four main chemicals may be useful for treating AD- and UC-related complications, the embedded homoorientin coated with ursolic acid even demonstrated stronger bioavailability than homoorientin. Considering BLF complexes were verified to suppress the progressions of AD and UC for the first time, and the embedded homoorientin was never reported in published articles, the present study might provide a new perspective on its potential applications.

The Role of Dietary Ingredients in Mental Energy - A Scoping Review of Randomized Controlled Trials

Low mental energy can contribute to decreased productivity, altered life balance, decreased physical performance, and ultimately affect quality of life. As such, there is a great demand for food and beverage products that positively impact mental energy. Numerous products claim to alter mental energy making continued review of the scientific evidence critical. The objective of this study was to conduct a scoping review of randomized controlled trials to evaluate the effect of 18 dietary ingredients on mental energy outcomes in adults without severe disease. Methods: A literature search, completed using PubMed, resulted in the identification of 2261 articles, 190 of which met eligibility from initial abstract review. Full-text review was completed on the 190 studies which resulted in 101 articles that fully met eligibility for inclusion in this study. The search strategy for two ingredients did not yield any eligible studies, leaving studies for 16 ingredients that were extracted and summarized by reported significantly improved outcomes for cognition, mood and perceived feelings, and sleep assessments. The preliminary results for several dietary ingredients directionally suggested a mental energy benefit (≥20% of outcomes), including ashwagandha, chamomile, dark chocolate, ginseng, green tea, lavender, lion's mane mushroom, maca, tart cherries, turmeric, and valerian root. The results of this scoping review suggest that of the 16 dietary ingredients reviewed, 11 may be promising for further exploration on their potential benefits in supporting mental energy. Given consumer demand and market growth for food and beverage products that positively impact mental energy; continued efforts in assessment method alignment and additional evaluation in well-designed trials is warranted.KEY TEACHING POINTSOf the 16 dietary ingredients reviewed, 11 (ashwagandha, chamomile, dark chocolate, ginseng, green tea, lavender, lion's mane mushroom, maca, melatonin foods, turmeric, and valerian root) may be promising for further exploration on their potential mental energy benefits.Dark chocolate, ginseng, ashwagandha, and lion's mane mushroom were the most promising ingredients for further evaluation in the cognition domain of the ingredients evaluated.Turmeric, maca, lavendar, and ashwagandha were the most promising ingredients for further evaluation in the mood and perceived feelings domain of the ingredients evaluated.Ashwagandha, chamomile, green tea, melatonin foods, valerian root were the most promising ingredients for further evaluation in the sleep domain of the ingredients evaluated.Additional, well-designed, consistent, clinical trials and systematic reviews are warranted as the challenge of heterogeneity in mental energy study design remains.

Epigallocatechin-3-Gallate and Genistein for Decreasing Gut Dysbiosis, Inhibiting Inflammasomes, and Aiding Autophagy in Alzheimer's Disease

There are approximately 24 million cases of Alzheimer's disease (AD) worldwide, and the number of cases is expected to increase four-fold by 2050. AD is a neurodegenerative disease that leads to severe dementia in most patients. There are several neuropathological signs of AD, such as deposition of amyloid beta (Aβ) plaques, formation of neurofibrillary tangles (NFTs), neuronal loss, activation of inflammasomes, and declining autophagy. Several of these hallmarks are linked to the gut microbiome. The gastrointestinal (GI) tract contains microbial diversity, which is important in regulating several functions in the brain via the gut-brain axis (GBA). The disruption of the balance in the gut microbiota is known as gut dysbiosis. Recent studies strongly support that targeting gut dysbiosis with selective bioflavonoids is a highly plausible solution to attenuate activation of inflammasomes (contributing to neuroinflammation) and resume autophagy (a cellular mechanism for lysosomal degradation of the damaged components and recycling of building blocks) to stop AD pathogenesis. This review is focused on two bioflavonoids, specifically epigallocatechin-3-gallate (EGCG) and genistein (GS), as a possible new paradigm of treatment for maintaining healthy gut microbiota in AD due to their implications in modulating crucial AD signaling pathways. The combination of EGCG and GS has a higher potential than either agent alone to attenuate the signaling pathways implicated in AD pathogenesis. The effects of EGCG and GS on altering gut microbiota and GBA were also explored, along with conclusions from various delivery methods to increase the bioavailability of these bioflavonoids in the body.

Dietary (Poly)phenols and Cognitive Decline: A Systematic Review and Meta-Analysis of Observational Studies

SCOPE

This study aims to systematically review observational studies investigating the relation between dietary (poly)phenol consumption and various cognitive outcomes.

METHODS AND RESULTS

Embase and PubMed databases are searched from inception to April 2023 for observational studies investigating the relation between dietary (poly)phenol intake and cognitive outcomes. For quantitative analyses, random effects models, subgroup analyses, and dose-response analyses are performed. A total of 37 studies are included in the systematic review. Among (poly)phenols, a higher intake of flavonoids is associated with better cognitive function and lower odds of cognitive decline (although with some exceptions). A quantitative meta-analysis shows an overall inverse association with cognitive impairment and reduced association with the incidence of dementia or related disorders for total flavonoids (relative risk (RR) = 0.83, 95% confidence interval (CI): 0.76, 0.89), anthocyanins (RR = 0.73, 95% CI: 0.60, 0.89), flavones (RR = 0.77, 95% CI: 0.63, 0.94), flavan-3-ols (RR = 0.86, 95% CI: 0.82, 0.91), and flavonols (RR = 0.88, 95% CI: 0.80, 0.96). Data on other (poly)phenolic compounds (i.e., phenolic acids) are promising but too preliminary.

CONCLUSION

Habitual inclusion of flavonoids in the diet may play a preventive role against cognitive disorders.

Pathogenesis of Neurodegenerative Diseases and the Protective Role of Natural Bioactive Components

Neurodegenerative diseases are a serious problem throughout the world. There are several causes of neurodegenerative diseases; these include genetic predisposition, accumulation of misfolded proteins, oxidative stress, neuroinflammation, and excitotoxicity. Oxidative stress increases the production of reactive oxygen species (ROS) that advance lipid peroxidation, DNA damage, and neuroinflammation. The cellular antioxidant system (superoxide dismutase, catalase, peroxidase, and reduced glutathione) plays a crucial role in scavenging free radicals. An imbalance in the defensive actions of antioxidants and overproduction of ROS intensify neurodegeneration. The formation of misfolded proteins, glutamate toxicity, oxidative stress, and cytokine imbalance promote the pathogenesis of Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. Antioxidants are now attractive molecules to fight against neurodegeneration. Certain vitamins (A, E, C) and polyphenolic compounds (flavonoids) show excellent antioxidant properties. Diet is the major source of antioxidants. However, diet medicinal herbs are also rich sources of numerous flavonoids. Antioxidants prevent ROS-mediated neuronal degeneration in post-oxidative stress conditions. The present review is focused on the pathogenesis of neurodegenerative diseases and the protective role of antioxidants. KEY TEACHING POINTSThis review shows that multiple factors are directly or indirectly associated with the pathogenesis of neurodegenerative diseases.Failure to cellular antioxidant capacity increases oxidative stress that intensifies neuroinflammation and disease progression.Different vitamins, carotenoids, and flavonoids, having antioxidant capacity, can be considered protective agents.

Effect of MIND diet on cognitive function in elderly: a narrative review with emphasis on bioactive food ingredients

As the world becomes a super-aged society, cognitive decline is public health problems that are increasing rapidly. A healthy diet has great potential for maintaining cognitive health. A diet that could delay the onset of neurodegenerative diseases has been developed: the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, a hybrid form of the Mediterranean diet and the Dietary Approaches to Stop Hypertension (DASH) diet. In this review, the effects of the MIND diet on improving cognitive function, including memory, are summarized. In most studies, the higher the adherence to the MIND diet, the higher the cognitive function evaluation score, and the lower the incidence of dementia. This is because of the anti-inflammatory and antioxidant effects of the major nutritional components of the MIND diet: folate, carotenoids, polyphenols, and polyunsaturated fatty acids. Adherence to the MIND diet, containing various bioactive food ingredients, is related to cognitive improvement in the elderly population.

Therapeutic potential of flavonoids in the management of obesity-induced Alzheimer's disease: an overview of preclinical and clinical studies

Obesity is a global epidemic that affects people of all ages, genders, and backgrounds. It can lead to a plethora of disorders, including diabetes mellitus, renal dysfunction, musculoskeletal problems, metabolic syndrome, cardiovascular, and neurodegenerative abnormalities. Obesity has also been linked to neurological diseases such as cognitive decline, dementia, and Alzheimer's disease (AD), caused by oxidative stress, pro-inflammatory cytokines, and the production of reactive oxygen free radicals (ROS). Secretion of insulin hormone is impaired in obese people, leading to hyperglycaemia and increased accumulation of amyloid-β in the brain. Acetylcholine, a key neurotransmitter necessary for forming new neuronal connections in the brain, decreases in AD patients. To alleviate acetylcholine deficiency, researchers have proposed dietary interventions and adjuvant therapies that enhance the production of acetylcholine and assist in the management of AD patients. Such measures include dietary intervention with antioxidant and anti-inflammatory flavonoid-rich diets, which have been found to bind to tau receptors, reduce gliosis, and reduce neuroinflammatory markers in animal models. Furthermore, flavonoids like curcumin, resveratrol, epigallocatechin-3-gallate, morin, delphinidins, quercetin, luteolin, and oleocanthal have shown to cause significant reductions in interleukin-1β, increase BDNF levels, stimulate hippocampal neurogenesis and synapse formation, and ultimately prevent the loss of neurons in the brain. Thus, flavonoid-rich nutraceuticals can be a potential cost-effective therapeutic option for treating obesity-induced AD, but further well-designed, randomized, and placebo-controlled clinical studies are needed to assess their optimal dosages, efficacy, and long-term safety of flavonoids in humans. The main objectives of this review are to underscore the therapeutic potential of different nutraceuticals containing flavonoids that can be added in the daily diet of AD patients to enhance acetylcholine and reduce neuronal inflammation in the brain.

Valorization and characterization of corn by-product polyphenols through green extraction technologies

The amount of food waste throughout the world has become quite alarming and is contributing to lower food resources. The study aimed to extract and characterize the polyphenols from corn silks at immature and mature stages through conventional and green extraction techniques. Purposely, corn silks, which are some of the by-products of corn, (Zea mays L.) were collected and subjected to proximate analysis including moisture, ash, protein, fiber, and minerals. Secondly, the antioxidants from both immature and mature corn silks were extracted by techniques involving supercritical and ultrasound extraction alongside conventional extraction. The results displayed a promising quantity of protein and fiber along with calcium, magnesium, sodium potassium, and copper. Among the extraction techniques, supercritical extraction at 3,000 Pa acquired the highest total phenolic contents (TPC), total flavonoids (TF), 2, 2-diphenylpicrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP) activities as 128.08 ± 3.74 mg GAE/100 g, 86.73 ± 2.75 mg CE/100 g, 106.73 ± 5.10%, and 73.52 ± 2.33 μM Fe + 2/g, respectively, followed by the ultrasound and conventional extraction techniques. Between the immature and mature corn silks, the highest antioxidant activity was displayed by immature corn silks.

Flavonoids and their therapeutic applications in skin diseases

Flavonoids are a class of plant polyphenols found in a variety of fruits, vegetables, teas, and flowers. These compounds are present in many common dietary sources, such as green tea, wine, pomegranates, and turmeric, and possess a broad spectrum of biological activity due to their unique chemical structure. Flavonoids exhibit antioxidant, anti-inflammatory, antiviral, and anticarcinogenic properties that have been widely studied as potential therapeutics for diseases ranging from Alzheimer's disease to liver disease. There is currently significant research into therapeutic benefits of flavonoids in various skin conditions as these compounds have been shown to absorb ultraviolet radiation and modulate cancer and inflammation signaling pathways. This review discusses the current research in the application of flavonoids in skin diseases (e.g., prevention of premature photoaging, prevention and treatment of skin cancer, and promotion of skin wound healing) and their proposed mechanisms to provide a basis for future basic and translational research of flavonoids as potential drugs in the prevention and treatment of skin disorders.

Flavonoids and their therapeutic applications in skin diseases

Flavonoids are a class of plant polyphenols found in a variety of fruits, vegetables, teas, and flowers. These compounds are present in many common dietary sources, such as green tea, wine, pomegranates, and turmeric, and possess a broad spectrum of biological activity due to their unique chemical structure. Flavonoids exhibit antioxidant, anti-inflammatory, antiviral, and anticarcinogenic properties that have been widely studied as potential therapeutics for diseases ranging from Alzheimer's disease to liver disease. There is currently significant research into therapeutic benefits of flavonoids in various skin conditions as these compounds have been shown to absorb ultraviolet radiation and modulate cancer and inflammation signaling pathways. This review discusses the current research in the application of flavonoids in skin diseases (e.g., prevention of premature photoaging, prevention and treatment of skin cancer, and promotion of skin wound healing) and their proposed mechanisms to provide a basis for future basic and translational research of flavonoids as potential drugs in the prevention and treatment of skin disorders.

Effects of cocoa extract and a multivitamin on cognitive function: A randomized clinical trial

INTRODUCTION

Dietary supplements are touted for cognitive protection, but supporting evidence is mixed. COSMOS-Mind tested whether daily administration of cocoa extract (containing 500 mg/day flavanols) versus placebo and a commercial multivitamin-mineral (MVM) versus placebo improved cognition in older women and men.

METHODS

COSMOS-Mind, a large randomized two-by-two factorial 3-year trial, assessed cognition by telephone at baseline and annually. The primary outcome was a global cognition composite formed from mean standardized (z) scores (relative to baseline) from individual tests, including the Telephone Interview of Cognitive Status, Word List and Story Recall, Oral Trail-Making, Verbal Fluency, Number Span, and Digit Ordering. Using intention-to-treat, the primary endpoint was change in this composite with 3 years of cocoa extract use. The pre-specified secondary endpoint was change in the composite with 3 years of MVM supplementation. Treatment effects were also examined for executive function and memory composite scores, and in pre-specified subgroups at higher risk for cognitive decline.

RESULTS

A total of 2262 participants were enrolled (mean age = 73y; 60% women; 89% non-Hispanic White), and 92% completed the baseline and at least one annual assessment. Cocoa extract had no effect on global cognition (mean z-score = 0.03, 95% CI: -0.02 to 0.08; P = .28). Daily MVM supplementation, relative to placebo, resulted in a statistically significant benefit on global cognition (mean z = 0.07, 95% CI 0.02 to 0.12; P = .007), and this effect was most pronounced in participants with a history of cardiovascular disease (no history: 0.06, 95% CI 0.01 to 0.11; history: 0.14, 95% CI -0.02 to 0.31; interaction, nominal P = .01). Multivitamin-mineral benefits were also observed for memory and executive function. The cocoa extract by MVM group interaction was not significant for any of the cognitive composites.

DISCUSSION

Cocoa extract did not benefit cognition. However, COSMOS-Mind provides the first evidence from a large, long-term, pragmatic trial to support the potential efficacy of a MVM to improve cognition in older adults. Additional work is needed to confirm these findings in a more diverse cohort and to identify mechanisms to account for MVM effects.

HIGHLIGHTS

COSMOS-Mind was a large simple pragmatic randomized clinical trial in older adults conducted by mail and telephone. The trial used a two-by-two factorial design to assess treatment effects of two different interventions within a single large study. We found no cognitive benefit of daily cocoa extract administration (containing 500 mg flavanols) for 3 years. Daily multivitamin-mineral (MVM) supplementation for 3 years improved global cognition, episodic memory, and executive function in older adults. The MVM benefit appeared to be greater for adults with cardiovascular disease.

Effect of Avena sativa (Oats) on cognitive function: A systematic review of randomized controlled trials

BACKGROUND AND AIM

The effect of polyphenol-rich diets or supplements on cognitive function remains a contentious topic. The objective of this study was to investigate the effects of Avena sativa (oat extracts) on cognitive function among healthy adults.

METHODS

A structured literature search was undertaken using PubMed, Web of Science, and Scopus from the database's establishment until March 17, 2022. Data on cognitive function, regarding accuracy and speed of performance, were gathered from randomized controlled trials (RCTs) that investigated the acute or chronic effects of Avena sativa in healthy subjects. The Cochrane Collaboration risk-of-bias tool was used to assess the quality of included studies.

RESULTS

We included six RCTs, of which three were crossover designs, with a total of 287 individuals. Four studies investigated the acute effect of Avena sativa, while two investigated its chronic effect. Acute ingestion of Avena sativa appeared to positively influence the accuracy and speed of performance. While short-term chronic supplementation resulted in a significant improvement in cognitive function, long-term chronic supplementation did not. Overall, the evidence was of average quality.

CONCLUSION

Acute supplementation with Avena sativa may improve cognitive function in healthy volunteers. Given the small number of trials included and the disparity of the intervention dose, the conclusions of this study should be interpreted with caution. More high-quality, long-term studies are warranted.

An insight into the neuroprotective and anti-neuroinflammatory effects and mechanisms of Moringa oleifera

Neurodegenerative diseases (NDs) are sporadic maladies that affect patients' lives with progressive neurological disabilities and reduced quality of life. Neuroinflammation and oxidative reaction are among the pivotal factors for neurodegenerative conditions, contributing to the progression of NDs, such as Parkinson's disease (PD), Alzheimer's disease (AD), multiple sclerosis (MS) and Huntington's disease (HD). Management of NDs is still less than optimum due to its wide range of causative factors and influences, such as lifestyle, genetic variants, and environmental aspects. The neuroprotective and anti-neuroinflammatory activities of Moringa oleifera have been documented in numerous studies due to its richness of phytochemicals with antioxidant and anti-inflammatory properties. This review highlights up-to-date research findings on the anti-neuroinflammatory and neuroprotective effects of M. oleifera, including mechanisms against NDs. The information was gathered from databases, which include Scopus, Science Direct, Ovid-MEDLINE, Springer, and Elsevier. Neuroprotective effects of M. oleifera were mainly assessed by using the crude extracts in vitro and in vivo experiments. Isolated compounds from M. oleifera such as moringin, astragalin, and isoquercitrin, and identified compounds of M. oleifera such as phenolic acids and flavonoids (chlorogenic acid, gallic acid, ferulic acid, caffeic acid, kaempferol, quercetin, myricetin, (-)-epicatechin, and isoquercitrin) have been reported to have neuropharmacological activities. Therefore, these compounds may potentially contribute to the neuroprotective and anti-neuroinflammatory effects. More in-depth studies using in vivo animal models of neurological-related disorders and extensive preclinical investigations, such as pharmacokinetics, toxicity, and bioavailability studies are necessary before clinical trials can be carried out to develop M. oleifera constituents into neuroprotective agents.

Dietary Flavonoids and Adult Neurogenesis: Potential Implications for Brain Aging

Adult neurogenesis deficiency has been proposed to be a common hallmark in different age-related neurodegenerative diseases. The administration of flavonoids is currently reported as a potentially beneficial strategy for preventing brain aging alterations, including adult neurogenesis decline. Flavonoids are a class of plant-derived dietary polyphenols that have drawn attention for their neuroprotective and pro-cognitive effects. Although they undergo extensive metabolism and localize in the brain at low concentrations, flavonoids are now believed to improve cerebral vasculature and interact with signal transduction cascades involved in the regulation of adult neurogenesis. Furthermore, many dietary flavonoids have been shown to reduce oxidative stress and neuroinflammation, improving the neuronal microenvironment where adult neurogenesis occurs. The overall goal of this review is to summarize the evidence supporting the role of flavonoids in modulating adult neurogenesis as well as to highlight how these dietary agents may be promising candidates in restoring healthy brain function during physiological and pathological aging.

Neurotrophic fragments as therapeutic alternatives to ameliorate brain aging

Aging is a global phenomenon and a complex biological process of all living beings that introduces various changes. During this physiological process, the brain is the most affected organ due to changes in its structural and chemical functions, such as changes in plasticity and decrease in the number, diameter, length, and branching of dendrites and dendritic spines. Likewise, it presents a great reduction in volume resulting from the contraction of the gray matter. Consequently, aging can affect not only cognitive functions, including learning and memory, but also the quality of life of older people. As a result of the phenomena, various molecules with notable neuroprotective capacity have been proposed, which provide a therapeutic alternative for people under conditions of aging or some neurodegenerative diseases. It is important to indicate that in recent years the use of molecules with neurotrophic activity has shown interesting results when evaluated in in vivo models. This review aims to describe the neurotrophic potential of molecules such as resveratrol (3,5,4′-trihydroxystilbene), neurotrophins (brain-derived neurotrophic factor), and neurotrophic-type compounds such as the terminal carboxyl domain of the heavy chain of tetanus toxin, cerebrolysin, neuropeptide-12, and rapamycin. Most of these molecules have been evaluated by our research group. Studies suggest that these molecules exert an important therapeutic potential, restoring brain function in aging conditions or models of neurodegenerative diseases. Hence, our interest is in describing the current scientific evidence that supports the therapeutic potential of these molecules with active neurotrophic.

Euonymus alatus Twig Extract Protects against Scopolamine-Induced Changes in Brain and Brain-Derived Cells via Cholinergic and BDNF Pathways

In the current study, the therapeutic and preventive effects of Euonymus alatus (EA) twig extract were investigated in a mouse model of cognitive deficit and B35 cells. Twig extract 1 was extracted with 70% ethanol and later twig extract 2 was extracted through liquid-liquid extraction with 70% ethanol and hexane. EA twig 2 (300 mg/kg) along with the standard drug donepezil (5 mg/kg) were orally administered to the mice for 34 days. Scopolamine was given intraperitoneally for 7 days. Administration of EA twig extract 2 significantly improved the passive avoidance test (PAT) in mice. EA twigs extract also restored the scopolamine-reduced brain-derived neurotrophic factor (BDNF)/extracellular regulated kinase (ERK)/cyclic AMP responsive element binding protein (CREB) signaling in B35 cells and the mouse hippocampus. In addition, EA twig extract significantly inhibited the acetylcholine esterase (AChE) activity in B35 cells in a dose-dependent manner. Chromatography and ESI MS analysis of EA twig extract revealed the presence of flavonoids; epicatechin, taxifolin, aromadendrin, and naringenin with catechin being the most abundant. These flavonoids exerted protective effects alone and had the possibility of synergistic effects in combination. Our work unmasks the ameliorating effect of EA twig extract 2 on scopolamine-associated cognitive impairments through the restoration of cholinergic systems and the BDNF/ERK/CREB pathway.

Naringenin: A prospective therapeutic agent for Alzheimer's and Parkinson's disease

Neurodegenerative disorders (NDs) are a cluster of progressive, severe, and disabling disorders that affect millions of people worldwide and are on the surge. These disorders are characterized by the gradual loss of a selectively vulnerable group of neurons. Due to the complex pathophysiological mechanisms behind neurodegeneration and despite enormous efforts and understanding of the occurrence and progression of NDs, there is still a lack of an effective treatment for such diseases. Therefore, the development of a new therapeutic strategy for NDs is an unmet clinical need. Various natural compounds extracted from medicinal plants or fruits have shown promising activities in treating different types of NDs by targeting multiple signaling pathways. Among natural entities, flavonoids have incited a rise in public and scientific interest in recent years because of their purported health-promoting effects. Dietary supplementation of flavonoids has been shown to mitigate the severity of NDs such as Parkinson's disease (PD), Alzheimer's disease (AD), and dementia by their antioxidant effects. Naringenin is a citrus flavonoid that is known to possess numerous biological activities like antioxidant, anti-proliferative, and anti-inflammatory activities. Therefore, naringenin has emerged as a potential therapeutic agent that exerts preventive and curative effects on several neurological disorders. Increasing evidence has attained special attention on the variety of therapeutic targets along with complex signaling pathways of naringenin, which suggest its possible therapeutic applications in several NDs. Derived from the results of several pre-clinical research and considering the therapeutic effects of this compound, this review focuses on the potential role of naringenin as a pharmacological agent for the treatment and management of Alzheimer's and Parkinson's disease. The overall neuroprotective effects and different possible underlying mechanisms related to naringenin are discussed. In the light of substantial evidence for naringenin's neuroprotective efficacy in several experimental paradigms, this review suggests that this molecule should be investigated further as a viable candidate for the management of Alzheimer's and Parkinson's disease, with an emphasis on mechanistic and clinical trials to determine its efficacy. PRACTICAL APPLICATIONS: Naringenin is a flavanone, aglycone of Naringin, predominantly found in citrus fruits with a variety of pharmacological actions. Naringenin has been shown to exhibit remarkable therapeutic efficacy and has emerged as a potential therapeutic agent for the management of a variety of diseases such as various heart, liver, and metabolic disorders. Similarly, it has shown efficacy in neurodegenerative illnesses. Therefore, this review enables us to better understand the neuroprotective effects and different possible underlying mechanisms of naringenin. Also, this review provides a new indication to manage the symptoms of NDs like AD and PD. Furthermore, naringenin will be useful in the field of medicine as a new active ingredient for the treatment of neurodegenerative disorders like AD and PD.

An aqueous macerate of Ziziphus jujuba reduces long-term spatial memory impairment in D-galactose treated rats: role of anti-inflammatory pathways

Pharmacological treatments against Alzheimer disease provide only symptomatic relief and are associated with numerous side effects. Previous studies showed that a concoction of Ziziphus jujuba leaves possesses anti-amnesic effects in scopolamine-treated rats. More recently, an aqueous macerate of Z. jujuba leaves has been shown to reduce short-term memory impairment in D-galactose-treated rats. However, no study on the effect of an aqueous macerate of Z. jujuba on long-term memory impairment was performed. Therefore, this study evaluates the effect of an aqueous macerate of Z. jujuba on long-term spatial memory impairment in D-galactose-treated rats. Long-term spatial memory impairment was induced in rats by administering D-galactose (350 mg/kg/day, s.c.), once dailyfor 21 days. On the 22nd day, the integrity of this memory was assessed using the Morris water maze task. Rats that developed memory impairment were treated with tacrine (10 mg/kg, p.o.), or aspirin (20 mg/kg, p.o.), or extract (41.5, 83, and 166 mg/kg, p.o.), once daily, for 14 days. At the end of the treatment, memory impairment was once more assessed using the same paradigm. Animals were then euthanized, and some pro-inflammatory cytokine markers were analyzed in the hippocampus or blood. The extract at all doses significantly reduced the latency to attain the platforming of the water maze test. The extract (83 mg/kg) also increased the time spent in the target quadrant during the retention phase. The extract markedly reduced the concentration of pro-inflammatory cytokine markers in the hippocampus and blood. Together, these results suggest that this aqueous extract Z. jujuba reduces long-term spatial memory impairment. This effect may be mediated in part by its anti-inflammatory activity.

Continuous Exposure to Alpha-Glycosyl Isoquercitrin from Gestation Ameliorates Disrupted Hippocampal Neurogenesis in Rats Induced by Gestational Injection of Valproic Acid

This study examined the ameliorating effect of alpha-glycosyl isoquercitrin (AGIQ), an antioxidant, on disrupted hippocampal neurogenesis in the dentate gyrus (DG) in a rat model of autism spectrum disorder induced by prenatal valproic acid (VPA) exposure. Dams were intraperitoneally injected with 500 mg/kg VPA on gestational day 12. AGIQ was administered in the diet at 0.25 or 0.5% to dams from gestational day 13 until weaning at postnatal day (PND) 21 and then to pups until PND 63. At PND 21, VPA-exposed offspring showed decreased numbers of type-2a and type-3 neural progenitor cells (NPCs) among granule cell lineage subpopulations. AGIQ treatment at both doses rescued the reduction in type-3 NPCs. AGIQ upregulated Reln and Vldlr transcript levels in the DG at 0.5% and ≥ 0.25%, respectively, and increased the number of reelin⁺ interneurons in the DG hilus at 0.5%. AGIQ at 0.25% and/or 0.5% also upregulated Ntrk2, Cntf, Igf1, and Chrnb2. At PND 63, there were no changes in the granule cell lineage subpopulations in response to VPA or AGIQ. AGIQ at 0.25% increased the number of FOS⁺ granule cells, accompanied by Gria2 and Gria3 upregulation and increasing trend in the number of FOS⁺ granule cells at 0.5%. There was no definitive evidence of VPA-induced oxidative stress in the hippocampus throughout postnatal life. These results indicate that AGIQ ameliorates the VPA-induced disruption of hippocampal neurogenesis at weaning involving reelin, BDNF-TrkB, CNTF, and IGF1 signaling, and enhances FOS-mediated synaptic plasticity in adulthood, potentially through AMPA-receptor upregulation. The ameliorating effects of AGIQ may involve direct interactions with neural signaling cascades rather than antioxidant capacity.

The Neuroprotective Potentiality of Flavonoids on Alzheimer's Disease

Alzheimer's disease (AD), due to its spread, has become a global health priority, and is characterized by senile dementia and progressive disability. The main cause of AD and other neurodegenerations (Huntington, Parkinson, Amyotrophic Lateral Sclerosis) are aggregated protein accumulation and oxidative damage. Recent research on secondary metabolites of plants such as polyphenols demonstrated that they may slow the progression of AD. The flavonoids' mechanism of action in AD involved the inhibition of acetylcholinesterase, butyrylcholinesterase, Tau protein aggregation, β-secretase, oxidative stress, inflammation, and apoptosis through modulation of signaling pathways which are implicated in cognitive and neuroprotective functions, such as ERK, PI3-kinase/Akt, NFKB, MAPKs, and endogenous antioxidant enzymatic systems. This review focuses on flavonoids and their role in AD, in terms of therapeutic potentiality for human health, antioxidant potential, and specific AD molecular targets.

Multi-Target Mechanisms of Phytochemicals in Alzheimer’s Disease: Effects on Oxidative Stress, Neuroinflammation and Protein Aggregation

Alzheimer’s disease (AD) is a neurodegenerative disease characterized by a tangle-shaped accumulation of beta-amyloid peptide fragments and Tau protein in brain neurons. The pathophysiological mechanism involves the presence of Aβ-amyloid peptide, Tau protein, oxidative stress, and an exacerbated neuro-inflammatory response. This review aims to offer an updated compendium of the most recent and promising advances in AD treatment through the administration of phytochemicals. The literature survey was carried out by electronic search in the following specialized databases PubMed/Medline, Embase, TRIP database, Google Scholar, Wiley, and Web of Science regarding published works that included molecular mechanisms and signaling pathways targeted by phytochemicals in various experimental models of Alzheimer’s disease in vitro and in vivo. The results of the studies showed that the use of phytochemicals against AD has gained relevance due to their antioxidant, anti-neuroinflammatory, anti-amyloid, and anti-hyperphosphorylation properties of Tau protein. Some bioactive compounds from plants have been shown to have the ability to prevent and stop the progression of Alzheimer’s.

Therapeutic Effects and Metabolic Spectrum of Traditional Chinese Medicine Hengqing II Prescription on Alzheimer’s Disease

Alzheimer's disease (AD) seriously damages elders' social and daily abilities around the world. Traditional Chinese medicine (TCM), a rich drug resource bank, could help research AD. In order to explore the role of TCM in AD treatment, 86 AD patients were recruited from the hospital, then treated with Hengqing II prescription and donepezil hydrochloride. The cognitive and serum lipid levels were investigated before and after treatment. The patient's urine was collected after three months of treatment. Metabolites in the urine samples were extracted with methanol and detected on the UHPLC-MS platform. Results proved that Hengqing II can improve cognitive levels and reduce the levels of Hcy, D-D, FIB, Apo B, TC, and LDL-C compared with donepezil hydrochloride (P < 0.05). The results of multivariate statistical analysis revealed that the metabolism of HQII was significantly different compared with Control groups. A total of 66 differential metabolites were found in this comparison (50 were down-regulated and 16 were up-regulated). Four amino acid pathways and one linoleic acid pathway were found through these metabolites. After receiver operating characteristic analysis, it was suggested that palmitic acid, palmitoleic acid, linoleic acid, oleic acid, SAH, and methionine can be used as biomarkers for treating AD, while the effects of daidzein, genistein, and naringenin on the treatment of AD need to be further studied.

Cyrcadian Rhythm, Mood, and Temporal Patterns of Eating Chocolate: A Scoping Review of Physiology, Findings, and Future Directions

This paper discusses the effect of chrononutrition on the regulation of circadian rhythms; in particular, that of chocolate on the resynchronization of the human internal biological central and peripheral clocks with the main external synchronizers, light–dark cycle and nutrition-fasting cycle. The desynchronization of internal clocks with external synchronizers, which is so frequent in our modern society due to the tight rhythms imposed by work, social life, and technology, has a negative impact on our psycho-physical performance, well-being, and health. Taking small amounts of chocolate, in the morning at breakfast at the onset of the active phase, helps speed up resynchronization time. The high flavonoid contents in chocolate promote cardioprotection, metabolic regulation, neuroprotection, and neuromodulation with direct actions on brain function, neurogenesis, angiogenesis, and mood. Although the mechanisms of action of chocolate compounds on brain function and mood as well as on the regulation of circadian rhythms have yet to be fully understood, data from the literature currently available seem to agree in suggesting that chocolate intake, in compliance with chrononutrition, could be a strategy to reduce the negative effects of desynchronization. This strategy appears to be easily implemented in different age groups to improve work ability and daily life.

Epigallocatechin Gallate (EGCG) for Parkinson's Disease

In the last couple of decades, we have experienced increased use of nutraceuticals worldwide with a demand for organic foods, which has been elevated to an extent probably unmatched with other periods of our civilization. One of the nutraceuticals that gained attention is epigallocatechin gallate (EGCG), a polyphenol in green tea. It has been suggested that diseases of the central nervous system (CNS) can benefit from consuming some antioxidants, despite current results showing little evidence for their use in preventing and treating these diseases. ECGC may be beneficial in delaying the neurodegeneration of the substantia nigra (SN) regardless of the origin of Parkinson's disease (PD). This review covers the effect of EGCG on vitro and animal models of PD, the potential mechanisms of neuroprotection involved and summaries recent clinical trials in human PD. This review also aims to provide an investigative analysis of the current knowledge in this field and identify putative crucial issues. Environmental factors such as dietary habits, drug use, and social interaction are all factors that influence the evolution of neurodegenerative diseases. Therefore, the use of nutraceuticals requires further investigation. This article is protected by copyright. All rights reserved.

The combined effect of physical activity and fruit and vegetable intake on decreasing cognitive decline in older Taiwanese adults

The factors associated with cognitive decline among older adults include physical activity and fruit and vegetable intake. However, the long-term effects of concomitant physical activity and fruit and vegetable intake are unknown. This 16-year longitudinal study explored the joint effect of mitigating cognitive decline in a cohort of older Taiwanese individuals. Five population-based surveys (Taiwan Longitudinal Survey on Aging [1999–2015]) involving 4440 respondents over 53 years old in 1999 were conducted. Cognitive function was assessed using the Short Portable Mental Status Questionnaire (SPMSQ). The demographic, socioeconomic, health-related, behavioral, and disease status covariates were adjusted in the regression analysis. Trends in cognitive decline were observed over 16 years. The risk of cognitive decline decreased by 63% when high physical activity and high fruit and vegetable intake were combined (odds ratio 0.37; 95% confidence interval 0.23–0.59), indicating a potential combined effect of physical activity and fruit and vegetable intake on mitigating cognitive decline. These personal actions are safe, effective, and economical approaches to health promotion and disease prevention.

Catechins as a Potential Dietary Supplementation in Prevention of Comorbidities Linked with Down Syndrome

Plant-derived polyphenols flavonoids are increasingly being recognized for their medicinal potential. These bioactive compounds derived from plants are gaining more interest in ameliorating adverse health risks because of their low toxicity and few side effects. Among them, therapeutic approaches demonstrated the efficacy of catechins, a major group of flavonoids, in reverting several aspects of Down syndrome, the most common genomic disorder that causes intellectual disability. Down syndrome is characterized by increased incidence of developing Alzheimer's disease, obesity, and subsequent metabolic disorders. In this focused review, we examine the main effects of catechins on comorbidities linked with Down syndrome. We also provide evidence of catechin effects on DYRK1A, a dosage-sensitive gene encoding a protein kinase involved in brain defects and metabolic disease associated with Down syndrome.

Effect of providing purple sweet potato water extract on tumor necrosis factor-α levels, protein 53 expression, glial fibrillary acidic protein expression, brain-derived neurotrophic factor levels, and spatial working memory in rats with d-galactose induction

Alzheimer's dementia (AD) is a neurodegenerative disease. The mechanism of oxidative stress in AD is due to amyloid beta (Aβ) protein that aggregates to form plaques, which further triggers chronic inflammation and neuronal apoptosis. Purple sweet potato extract with the main content of anthocyanins is a potential antioxidant with a direct target on the amyloid cascade hypothesis.

Objective

The research objective was to determine the role of purple sweet potato water extract as an antioxidant and anti-inflammatory in preventing apoptosis in order to provide a neuroprotective effect in d-galactose-induced rats.

Methods

A total of 100 male Wistar rats with randomized posttest-only control group design that met the eligibility criteria were included in this study. The treatment group was given 200 mg/kg BW/day of purple sweet potato water extract on days 1-70. d-galactose induction was administered in the treatment and control groups on days 15-70.

Results

The independent t-test showed that the mean tumor necrosis factor-α (TNF-α) levels in the treatment group (735.36±139.74) was significantly lower than that in the control group (896.77±152.52). The p53 and glial fibrillary acidic protein (GFAP) expressions of astrocyte cells in the treatment group were significantly lower than that in the control group. The brain-derived neurotrophic factor (BDNF) levels in the treatment group (498.13±121.47) were higher than that in the control (391.93±140.28), and there was a significant increase in spatial working memory in the treatment group (72.01±10.22) than the control (59.77±11.87).

Conclusions

The neuroprotective effect of purple sweet potato extract is due to d-galactose induction resulting from decrease in TNF-α levels, p53 expression, and GFAP expression and increase in BDNF levels and spatial working memory.

The effects of festidinol treatment on the D-galactose and aluminum chloride-induced Alzheimer-like pathology in mouse brain

BACKGROUND

Festidinol is a flavan-3-ol which has been shown to reduce advanced glycation end products (AGEs) and reactive oxygen species, both of which play a crucial role in the pathology of many neurodegenerative diseases.

PURPOSE

This study aimed to investigate the effects of festidinol on oxidative stress, amyloidogenesis, phosphorylated tau (pTau) expression, synaptic function, and cognitive impairment, and the potential mechanisms involved, in a mouse model with an Alzheimer-like pathology.

METHODS

D-galactose (150 mg/kg) and aluminum chloride (10 mg/kg) were injected intraperitoneally into 40 mice for 90 days to generate an AD mouse model with cognitive impairment. Festidinol (30 mg/kg) and donepezil (5 mg/kg) were then administered orally for 90 days after which behavior and molecular changes in the brain were measured.

RESULTS

The aluminum accumulated and the expression of the cell senescence marker P16 increased after exposure to D-galactose and AlCl3 (2.5 ± 0.5 mg/kg, 149.1 ± 28.1% of control, respectively). Festidinol markedly decreased the escape latency (8.7 ± 4.3 s) and increased the number of platform crossings (8 ± 1.4 time) in the Morris water maze test. Superoxide dismutase activity was significantly elevated after festidinol administration, however there were significant reductions in the levels of 4‑hydroxy-2-nonenal, receptor for advanced glycation end products, phosphorylated nuclear factor kappa-light-chain-enhancer of activated B cells (pNF-κB), and nuclear factor of activated T cells 1 (NFAT1). Festidinol attenuated amyloid beta production by reducing the mRNA of beta-site APP cleaving enzyme 1 (BACE1). Festidinol also significantly decreased the expression of pTau and phosphorylated glycogen synthase kinase 3 (148.6 ± 37.6% of control, 125.3 ± 22.6% of control, respectively).

CONCLUSION

Festidinol can ameliorate learning and memory impairments by modulating amyloidogenesis, tau hyperphosphorylation, cholinergic activity, neuroinflammation, and oxidative stress, and by regulating the brain-derived neurotrophic factor signaling pathway.

Red-Beet Betalain Pigments Inhibit Amyloid-β Aggregation and Toxicity in Amyloid-β Expressing Caenorhabditis elegans

Betalain pigments are mainly produced by plants belonging to the order of Caryophyllales. Betalains exhibit strong antioxidant activity and responds to environmental stimuli and stress in plants. Recent reports of antioxidant, anti-inflammatory and anti-cancer properties of betalain pigments have piqued interest in understanding their biological functions. We investigated the effects of betalain pigments (betanin and isobetanin) derived from red-beet on amyloid-β (Aβ) aggregation, which causes Alzheimer's disease. Non-specific inhibition of Aβ aggregation against Aβ40 and Aβ42 by red-beet betalain pigments, in vitro was demonstrated using the thioflavin t fluorescence assay, circular dichroism spectroscopy analysis, transmission electron microscopy and nuclear magnetic resonance (NMR) analysis. Furthermore, we examined the ability of red-beet betalain pigments to interfere with Aβ toxicity by using the transgenic Caenorhabditis elegans model, which expresses the human Aβ42 protein intracellularly within the body wall muscle. It responds to Aβ-toxicity with paralysis and treatment with 50 μM red-beet betalain pigments significantly delayed the paralysis of C. elegans. These results suggest that betalain pigments reduce Aβ-induced toxicity.

An ethnopharmacological review on the therapeutical properties of flavonoids and their mechanisms of actions: A comprehensive review based on up to date knowledge

Flavonoids -a class of low molecular weight secondary metabolites- are ubiquitous and cornucopia throughout the plant kingdom. Structurally, the main structure consists of C6-C3-C6 rings with different substitution patterns so that many sub-classes are obtained, for example: flavonols, flavonolignans, flavonoid glycosides, flavans, anthocyanidins, aurones, anthocyanidins, flavones, neoflavonoids, chalcones, isoflavones, flavones and flavanones. Flavonoids are evaluated to have drug like nature since they possess different therapeutic activities, and can act as cardioprotective, antiviral, antidiabetic, anti-inflammatory, antibacterial, anticancer, and also work against Alzheimer's disease and others. However, information on the relationship between their structure and biological activity is scarce. Therefore, the present review tries to summarize all the therapeutic activities of flavonoids, their mechanisms of action and the structure activity relationship.

•

Latest updated ethnopharmacological review of the therapeutic effects of flavonoids.

•

Flavonoids are attracting attention because of their therapeutic properties.

•

Flavonoids are valuable candidates for drug development against many dangerous diseases.

•

This overview summarizes the most important therapeutic effect and mechanism of action of flavonoids.

•

General knowledge about the structure activity relationship of flavonoids is summarized.

•

Substitution of chemical groups in the structure of flavonoids can significantly change their biological and chemical properties.

•

The chemical properties of the basic flavonoid structure should be considered in a drug-based structural program.

A Major Diplotaxis harra-Derived Bioflavonoid Glycoside as a Protective Agent against Chemically Induced Neurotoxicity and Parkinson's Models; In Silico Target Prediction; and Biphasic HPTLC-Based Quantification

Oxidative stress and chronic inflammation have a role in developing neurodegenerative diseases such as Parkinson’s disease (PD) and inflammatory movement disorders such as rheumatoid arthritis that affect millions of populations. In searching for antioxidant and anti-inflammatory molecules from natural sources that can counteract neurodegenerative diseases and arthritis, the flavonoid-rich extract of Diplotaxis harra (DHE) was selected based on its in vitro antioxidant and anti-inflammatory activities. DHE could inhibit the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in the lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages from 100% to the level of 28.51 ± 18.67 and 30.19 ± 5.00% at 20 μg/mL, respectively. A TLC bioautography of DHE fractions using 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) led to the isolation of a major antioxidant compound which was identified by X-ray diffraction analysis as isorhamnetin-3-O-β-D-glucoside (IR3G). IR3G also exhibited a potent anti-inflammatory activity, particularly by suppressing the upregulation of iNOS expression, similar to that of dexamethasone (DEX) at 10 μM to the level of 35.96 ± 7.80 and 29.34 ± 6.34%, respectively. Moreover, IR3G displayed a strong neuroprotectivity (>60% at 1.0−4−1.0−3 μM) against 6-hydroxydopamine (6-OHDA)-challenged SHSY5Y neuroblastoma, an in vitro model of dopaminergic neurons for Parkinson’s disease (PD) research. Accordingly, the in vivo anti-Parkinson potentiality was evaluated, where it was found that IR3G successfully reversed the 6-OHDA-induced locomotor deficit in a zebrafish model. A study of molecular docking and molecular dynamic (MD) simulation of IR3G and its aglycone isorhamnetin (IR) against human acetylcholine esterase (AChE), monoamine oxidase B (MAO-B), and Polo-like kinase-2 (PLK2) was performed and further outlined a putative mechanism in modulating neurodegenerative diseases such as PD. The free radical scavenging, anti-inflammatory through anti-iNOS and anti-COX-2 expression, and neuroprotective activities assessed in this study would present partial evidence for the potentiality of D. harra-derived IR3G as a promising natural therapeutic agent against neurodegenerative diseases and inflammatory arthritis. Finally, a biphasic HPTLC method was developed to estimate the biomarker IR3G in D. harra quantitatively.

Enhancing the Cognitive Effects of Flavonoids With Physical Activity: Is There a Case for the Gut Microbiome?

Age-related cognitive changes can be the first indication of the progression to dementias, such as Alzheimer’s disease. These changes may be driven by a complex interaction of factors including diet, activity levels, genetics, and environment. Here we review the evidence supporting relationships between flavonoids, physical activity, and brain function. Recent in vivo experiments and human clinical trials have shown that flavonoid-rich foods can inhibit neuroinflammation and enhance cognitive performance. Improved cognition has also been correlated with a physically active lifestyle, and with the functionality and diversity of the gut microbiome. The great majority (+ 90%) of dietary flavonoids are biotransformed into phytoactive phenolic metabolites at the gut microbiome level prior to absorption, and these prebiotic flavonoids modulate microbiota profiles and diversity. Health-relevant outcomes from flavonoid ingestion may only be realized in the presence of a robust microbiome. Moderate-to-vigorous physical activity (MVPA) accelerates the catabolism and uptake of these gut-derived anti-inflammatory and immunomodulatory metabolites into circulation. The gut microbiome exerts a profound influence on cognitive function; moderate exercise and flavonoid intake influence cognitive benefits; and exercise and flavonoid intake influence the microbiome. We conclude that there is a potential for combined impacts of flavonoid intake and physical exertion on cognitive function, as modulated by the gut microbiome, and that the combination of a flavonoid-rich diet and routine aerobic exercise may potentiate cognitive benefits and reduce cognitive decline in an aging population, via mechanisms mediated by the gut microbiome. Mechanistic animal studies and human clinical interventions are needed to further explore this hypothesis.

Anxiolytic effect of the heartwood of Haematoxylum campechianum L. and sappanchalcone in an in vivo model in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Haematoxylum campechianum L., is a well-known plant in the southeast region of Mexico, where it is named as "palo tinto" or "palo de Campeche", in English there are vernacular names such as "redwood", "bloodwood tree" or "campeachy wood". Traditional medicine refers its use for the treatment of different disorders including depression.

AIM OF THE STUDY

Considering the traditional use of this plant for the alleviation of depression, the aim of this study was the evaluation of the anxiolytic effect of the methanolic and hydroalcoholic extracts from the heartwood of Haematoxylum campechianum L., and the sappanchalchone (Sapp). Additionally, it is presented the characterization of the new compound 4-hydroxyhematoxylol (2) isolated from the hydroalcoholic extract.

MATERIAL AND METHODS

The anxiolytic effect of the extracts and Sapp was evaluated by using the Elevated Plus Maze (EPM) additionally the sedative effect was assessed with the Open Field Test (OFT). The chemical characterization of Sapp and 2 was performing by 1D and 2D NMR experiments.

RESULTS

The EPM test showed that the administration of the plant extracts increased the percentage of time spent in open arms (76.32 ± 6.35 and 66.68 ± 20.64%, respectively for the methanolic and hydroalcoholic extracts), whereas the administration of Sapp increased the percentage of time spent in open arms by 60.07 ± 14.28%, these results are similar to Diazepam (DZP, positive control) which caused an increment of 74.06 ± 23.42%. For the OFT, all of the doses evaluated for both extracts and Sapp diminished the number of rearing (R) and total corssing (TC) behavior in a similar way to the positive control (DZO) and statistically different with respect to the vehicle.

CONCLUSION

The results obtained showed that the polar extracts from the heartwood of Haematoxylum campechianum L. possess both anxiolytic and sedative effect and that the chalcone-type compound Sapp, isolated from the methanolic extract, is partially responsible of these activities.

Ameliorating effect of continuous alpha-glycosyl isoquercitrin treatment starting from late gestation in a rat autism model induced by postnatal injection of lipopolysaccharides

The present study investigated the role of neuroinflammation and brain oxidative stress induced by neonatal treatment with lipopolysaccharides (LPS) on the development of autism spectrum disorder (ASD)-like behaviors and disruptive hippocampal neurogenesis in rats by exploring the chemopreventive effects of alpha-glycosyl isoquercitrin (AGIQ) as an antioxidant. AGIQ was dietary administered to dams at 0.25% or 0.5% (w/w) from gestational day 18 until postnatal day (PND) 21 on weaning and then to pups until the adult stage on PND 77. The pups were intraperitoneally injected with LPS (1 mg/kg body weight) on PND 3. At PND 6, LPS alone increased Iba1+ and CD68+ cell numbers without changing the CD163+ cell number and strongly upregulated pro-inflammatory cytokine gene expression (Il1a, Il1b, Il6, Nfkb1, and Tnf) in the hippocampus, and increased brain malondialdehyde levels. At PND 10, pups decreased ultrasonic vocalization (USV), suggesting the induction of pro-inflammatory responses and oxidative stress to trigger communicative deficits. By contrast, LPS alone upregulated Nfe2l2 expression at PND 6, increased Iba1+, CD68+, and CD163+ cell numbers, and upregulated Tgfb1 at PND 21, suggesting anti-inflammatory responses until the weaning period. However, LPS alone disrupted hippocampal neurogenesis at weaning and suppressed social interaction parameters and rate of freezing time at fear acquisition and extinction during the adolescent stage. On PND 77, neuroinflammatory responses had mostly disappeared; however, disruptive neurogenesis and fear memory deficits were sustained. AGIQ ameliorated most changes on acute pro-inflammatory responses and oxidative stress at PND 6, and the effects on USVs at PND 10 and neurogenesis and behavioral parameters throughout the adult stage. These results suggested that neonatal LPS treatment induced acute but transient neuroinflammation, triggering the progressive disruption of hippocampal neurogenesis leading to abnormal behaviors in later life. AGIQ treatment was effective for ameliorating LPS-induced progressive changes by critically suppressing initial pro-inflammatory responses and oxidative stress.

Investigation of the interactions between three flavonoids and human serum albumin by isothermal titration calorimetry, spectroscopy, and molecular docking

The interactions between three flavonoids (liquiritin, quercitrin, and taxifolin) and human serum albumin (HSA) are investigated by spectroscopic techniques, isothermal titration calorimetry (ITC), and molecular docking study. Results show that...

Mental Performance and Sport: Caffeine and Co-consumed Bioactive Ingredients

The plant defence compound caffeine is widely consumed as a performance enhancer in a sporting context, with potential benefits expected in both physiological and psychological terms. However, although caffeine modestly but consistently improves alertness and fatigue, its effects on mental performance are largely restricted to improved attention or concentration. It has no consistent effect within other cognitive domains that are important to sporting performance, including working memory, executive function and long-term memory. Although caffeine's central nervous system effects are often attributed to blockade of the receptors for the inhibitory neuromodulator adenosine, it also inhibits a number of enzymes involved both in neurotransmission and in cellular homeostasis and signal propagation. Furthermore, it modulates the pharmacokinetics of other endogenous and exogenous bioactive molecules, in part via interactions with shared cytochrome P450 enzymes. Caffeine therefore enjoys interactive relationships with a wide range of bioactive medicinal and dietary compounds, potentially broadening, increasing, decreasing, or modulating the time course of their functional effects, or vice versa. This narrative review explores the mechanisms of action and efficacy of caffeine and the potential for combinations of caffeine and other dietary compounds to exert psychological effects in excess of those expected following caffeine alone. The review focusses on, and indeed restricted its untargeted search to, the most commonly consumed sources of caffeine: products derived from caffeine-synthesising plants that give us tea (Camellia sinensis), coffee (Coffea genus), cocoa (Theabroma cacao) and guaraná (Paullinia cupana), plus multi-component energy drinks and shots. This literature suggests relevant benefits to mental performance that exceed those associated with caffeine for multi-ingredient energy drinks/shots and several low-caffeine extracts, including high-flavanol cocoa and guarana. However, there is a general lack of research conducted in such a way as to disentangle the relative contributions of the component parts of these products.

Role of Phenolic Compounds in Human Disease: Current Knowledge and Future Prospects

Inflammation is a natural protective mechanism that occurs when the body's tissue homeostatic mechanisms are disrupted by biotic, physical, or chemical agents. The immune response generates pro-inflammatory mediators, but excessive output, such as chronic inflammation, contributes to many persistent diseases. Some phenolic compounds work in tandem with nonsteroidal anti-inflammatory drugs (NSAIDs) to inhibit pro-inflammatory mediators' activity or gene expression, including cyclooxygenase (COX). Various phenolic compounds can also act on transcription factors, such as nuclear factor-κB (NF-κB) or nuclear factor-erythroid factor 2-related factor 2 (Nrf-2), to up-or downregulate elements within the antioxidant response pathways. Phenolic compounds can inhibit enzymes associated with the development of human diseases and have been used to treat various common human ailments, including hypertension, metabolic problems, incendiary infections, and neurodegenerative diseases. The inhibition of the angiotensin-converting enzyme (ACE) by phenolic compounds has been used to treat hypertension. The inhibition of carbohydrate hydrolyzing enzyme represents a type 2 diabetes mellitus therapy, and cholinesterase inhibition has been applied to treat Alzheimer's disease (AD). Phenolic compounds have also demonstrated anti-inflammatory properties to treat skin diseases, rheumatoid arthritis, and inflammatory bowel disease. Plant extracts and phenolic compounds exert protective effects against oxidative stress and inflammation caused by airborne particulate matter, in addition to a range of anti-inflammatory, anticancer, anti-aging, antibacterial, and antiviral activities. Dietary polyphenols have been used to prevent and treat allergy-related diseases. The chemical and biological contributions of phenolic compounds to cardiovascular disease have also been described. This review summarizes the recent progress delineating the multifunctional roles of phenolic compounds, including their anti-inflammatory properties and the molecular pathways through which they exert anti-inflammatory effects on metabolic disorders. This study also discusses current issues and potential prospects for the therapeutic application of phenolic compounds to various human diseases.

Impaired Brain Mitochondrial Bioenergetics in the Ts65Dn Mouse Model of Down Syndrome Is Restored by Neonatal Treatment with the Polyphenol 7,8-Dihydroxyflavone

Down syndrome (DS), a major genetic cause of intellectual disability, is characterized by numerous neurodevelopmental defects. Previous in vitro studies highlighted a relationship between bioenergetic dysfunction and reduced neurogenesis in progenitor cells from the Ts65Dn mouse model of DS, suggesting a critical role of mitochondrial dysfunction in neurodevelopmental alterations in DS. Recent in vivo studies in Ts65Dn mice showed that neonatal supplementation (Days P3–P15) with the polyphenol 7,8-dihydroxyflavone (7,8-DHF) fully restored hippocampal neurogenesis. The current study was aimed to establish whether brain mitochondrial bioenergetic defects are already present in Ts65Dn pups and whether early treatment with 7,8-DHF positively impacts on mitochondrial function. In the brain and cerebellum of P3 and P15 Ts65Dn pups we found a strong impairment in the oxidative phosphorylation apparatus, resulting in a deficit in mitochondrial ATP production and ATP content. Administration of 7,8-DHF (dose: 5 mg/kg/day) during Days P3–P15 fully restored bioenergetic dysfunction in Ts65Dn mice, reduced the levels of oxygen radicals and reinstated the hippocampal levels of PGC-1α. No pharmacotherapy is available for DS. From current findings, 7,8-DHF emerges as a treatment with a good translational potential for improving mitochondrial bioenergetics and, thus, mitochondria-linked neurodevelopmental alterations in DS.