The Potential Role of Polyphenols in Oxidative Stress and Inflammation Induced by Gut Microbiota in Alzheimer's Disease

Gut microbiota-host lipid crosstalk in Alzheimer's disease: implications for disease progression and therapeutics

Trillions of intestinal bacteria in the human body undergo dynamic transformations in response to physiological and pathological changes. Alterations in their composition and metabolites collectively contribute to the progression of Alzheimer's disease. The role of gut microbiota in Alzheimer's disease is diverse and complex, evidence suggests lipid metabolism may be one of the potential pathways. However, the mechanisms that gut microbiota mediate lipid metabolism in Alzheimer's disease pathology remain unclear, necessitating further investigation for clarification. This review highlights the current understanding of how gut microbiota disrupts lipid metabolism and discusses the implications of these discoveries in guiding strategies for the prevention or treatment of Alzheimer's disease based on existing data.

Gut instincts: Unveiling the connection between gut microbiota and Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disorder marked by neuroinflammation and gradual cognitive decline. Recent research has revealed that the gut microbiota (GM) plays an important role in the pathogenesis of AD through the microbiota-gut-brain axis. However, the mechanism by which GM and microbial metabolites alter brain function is not clearly understood. GM dysbiosis increases the permeability of the intestine, alters the blood-brain barrier permeability, and elevates proinflammatory mediators causing neurodegeneration. This review article introduced us to the composition and functions of GM along with its repercussions of dysbiosis in relation to AD. We also discussed the importance of the gut-brain axis and its role in communication. Later we focused on the mechanism behind gut dysbiosis and the progression of AD including neuroinflammation, oxidative stress, and changes in neurotransmitter levels. Furthermore, we highlighted recent developments in AD management, such as microbiota-based therapy, dietary interventions like prebiotics, probiotics, and fecal microbiota transplantation. Finally, we concluded with challenges and future directions in AD research based on GM.

Dietary polyphenols represent a phytotherapeutic alternative for gut dysbiosis associated neurodegeneration: A systematic review

Globally, neurodegeneration and cerebrovascular disease are common and growing causes of morbidity and mortality. Pathophysiology of this group of diseases encompasses various factors from oxidative stress to gut microbial dysbiosis. The study of the etiology and mechanisms of oxidative stress as well as gut dysbiosis-induced neurodegeneration in Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis, autism spectrum disorder, and Huntington's disease has recently received a lot of attention. Numerous studies lend credence to the notion that changes in the intestinal microbiota and enteric neuroimmune system have an impact on the initiation and severity of these diseases. The prebiotic role of polyphenols can influence the makeup of the gut microbiota in neurodegenerative disorders by modulating intracellular signalling pathways. Metabolites of polyphenols function directly as neurotransmitters by crossing the blood-brain barrier or indirectly via influencing the cerebrovascular system. This assessment aims to bring forth an interlink between the consumption of polyphenols biotransformed by gut microbiota which in turn modulate the gut microbial diversity and biochemical changes in the brain. This systematic review will further augment research towards the association of dietary polyphenols in the management of gut dysbiosis-associated neurodegenerative diseases.

Oxidative stress in Alzheimer's disease: current knowledge of signaling pathways and therapeutics

Alzheimer's disease's pathophysiology is still a conundrum. Growing number of evidences have elucidated the involvement of oxidative stress in the pathology of AD rendering it a major target for therapeutic development. Reactive oxygen species (ROS) generated by altered mitochondrial function, dysregulated electron transport chain and other sources elevate aggregated Aβ and neurofibrillary tangles which further stimulating the production of ROS. Oxidative stress induced damage to lipids, proteins and DNA result in neuronal death which leads to AD. In addition, oxidative stress induces apoptosis that is triggered by the modulation of ERK1/2 and Nrf2 pathway followed by increased GSK-3β expression and decreased PP2A activity. Oxidative stress exaggerates disease condition by interfering with various signaling pathways like RCAN1, CREB/ERK, Nrf2, PP2A, NFκB and PI3K/Akt. Studies have reported the role of TNF-α in oxidative stress stimulation that has been regulated by drugs like etanercept increasing the level of anti-oxidants. Other drugs like pramipexole, memantine, carvedilol, and melatonin have been reported to activate CREB/RCAN1 and Nrf2 pathways. In line with this, epigallocatechin gallate and genistein also target Nrf2 and CREB pathway leading to activation of downstream pathways like ARE and Keap1 which ameliorate oxidative stress condition. Donepezil and resveratrol reduce oxidative stress and activate AMPK pathway along with PP2A activation thus promoting tau dephosphorylation and neuronal survival. This study describes in detail the role of oxidative stress in AD, major signaling pathways involving oxidative stress induced AD and drugs under development targeting these pathways which may aid in therapeutic advances for AD.

Microbiome in Cancer Development and Treatment

Targeting the microbiome, microbiota-derived metabolites, and related pathways represents a significant challenge in oncology. Microbiome analyses have confirmed the negative impact of cancer treatment on gut homeostasis, resulting in acute dysbiosis and severe complications, including massive inflammatory immune response, mucosal barrier disruption, and bacterial translocation across the gut epithelium. Moreover, recent studies revealed the relationship between an imbalance in the gut microbiome and treatment-related toxicity. In this review, we provide current insights into the role of the microbiome in tumor development and the impact of gut and tumor microbiomes on chemo- and immunotherapy efficacy, as well as treatment-induced late effects, including cognitive impairment and cardiotoxicity. As discussed, microbiota modulation via probiotic supplementation and fecal microbiota transplantation represents a new trend in cancer patient care, aiming to increase bacterial diversity, alleviate acute and long-term treatment-induced toxicity, and improve the response to various treatment modalities. However, a more detailed understanding of the complex relationship between the microbiome and host can significantly contribute to integrating a microbiome-based approach into clinical practice. Determination of causal correlations might lead to the identification of clinically relevant diagnostic and prognostic microbial biomarkers. Notably, restoration of intestinal homeostasis could contribute to optimizing treatment efficacy and improving cancer patient outcomes.

Harnessing the power of nutritional antioxidants against adrenal hormone imbalance-associated oxidative stress

Oxidative stress, resulting from dysregulation in the secretion of adrenal hormones, represents a major concern in human health. The present review comprehensively examines various categories of endocrine dysregulation within the adrenal glands, encompassing glucocorticoids, mineralocorticoids, and androgens. Additionally, a comprehensive account of adrenal hormone disorders, including adrenal insufficiency, Cushing's syndrome, and adrenal tumors, is presented, with particular emphasis on their intricate association with oxidative stress. The review also delves into an examination of various nutritional antioxidants, namely vitamin C, vitamin E, carotenoids, selenium, zinc, polyphenols, coenzyme Q10, and probiotics, and elucidates their role in mitigating the adverse effects of oxidative stress arising from imbalances in adrenal hormone levels. In conclusion, harnessing the power of nutritional antioxidants has the potential to help with oxidative stress caused by an imbalance in adrenal hormones. This could lead to new research and therapeutic interventions.

GLP-1 Analogs, SGLT-2, and DPP-4 Inhibitors: A Triad of Hope for Alzheimer's Disease Therapy

Alzheimer's is a prevalent, progressive neurodegenerative disease marked by cognitive decline and memory loss. The disease's development involves various pathomechanisms, including amyloid-beta accumulation, neurofibrillary tangles, oxidative stress, inflammation, and mitochondrial dysfunction. Recent research suggests that antidiabetic drugs may enhance neuronal survival and cognitive function in diabetes. Given the well-documented correlation between diabetes and Alzheimer's disease and the potential shared mechanisms, this review aimed to comprehensively assess the potential of new-generation anti-diabetic drugs, such as GLP-1 analogs, SGLT-2 inhibitors, and DPP-4 inhibitors, as promising therapeutic approaches for Alzheimer's disease. This review aims to comprehensively assess the potential therapeutic applications of novel-generation antidiabetic drugs, including GLP-1 analogs, SGLT-2 inhibitors, and DPP-4 inhibitors, in the context of Alzheimer's disease. In our considered opinion, antidiabetic drugs offer a promising avenue for groundbreaking developments and have the potential to revolutionize the landscape of Alzheimer's disease treatment.

Brain modulation by the gut microbiota: From disease to therapy

BACKGROUND

The gut microbiota (GM) and brain are strongly associated, which significantly affects neuronal development and disorders. GM-derived metabolites modulate neuronal function and influence many cascades in age-related neurodegenerative disorders (NDDs). Because of the dual role of GM in neuroprotection and neurodegeneration, understanding the balance between beneficial and harmful bacteria is crucial for applying this approach to clinical therapies.

AIM OF THE REVIEW

This review briefly discusses the role of the gut-brain relationship in promoting brain and cognitive function. Although a healthy gut environment is helpful for brain function, gut dysbiosis can disrupt the brain's environment and create a vicious cycle of degenerative cascades. The ways in which the GM population can affect brain function and the development of neurodegeneration are also discussed. In the treatment and management of NDDs, the beneficial effects of methods targeting GM populations and their derivatives, including probiotics, prebiotics, and fecal microbial transplantation (FMT) are also highlighted.

KEY SCIENTIFIC CONCEPT OF THE REVIEW

In this review, we aimed to provide a deeper understanding of the mechanisms of the gut microbe-brain relationship and their twin roles in neurodegeneration progression and therapeutic applications. Here, we attempted to highlight the different pathways connecting the brain and gut, together with the role of GM in neuroprotection and neuronal development. Furthermore, potential roles of GM metabolites in the pathogenesis of brain disorders and in strategies for its treatment are also investigated. By analyzing existing in vitro, in vivo and clinical studies, this review attempts to identify new and promising therapeutic strategies for central nervous system (CNS) disorders. As the connection between the gut microbe-brain relationship and responses to NDD treatments is less studied, this review will provide new insights into the global mechanisms of GM modulation in disease progression, and identify potential future perspectives for developing new therapies to treat NDDs.

Understanding the Gut-Brain Axis and Its Therapeutic Implications for Neurodegenerative Disorders

The gut-brain axis (GBA) is a complex bidirectional communication network connecting the gut and brain. It involves neural, immune, and endocrine communication pathways between the gastrointestinal (GI) tract and the central nervous system (CNS). Perturbations of the GBA have been reported in many neurodegenerative disorders (NDDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS), among others, suggesting a possible role in disease pathogenesis. The gut microbiota is a pivotal component of the GBA, and alterations in its composition, known as gut dysbiosis, have been associated with GBA dysfunction and neurodegeneration. The gut microbiota might influence the homeostasis of the CNS by modulating the immune system and, more directly, regulating the production of molecules and metabolites that influence the nervous and endocrine systems, making it a potential therapeutic target. Preclinical trials manipulating microbial composition through dietary intervention, probiotic and prebiotic supplementation, and fecal microbial transplantation (FMT) have provided promising outcomes. However, its clear mechanism is not well understood, and the results are not always consistent. Here, we provide an overview of the major components and communication pathways of the GBA, as well as therapeutic approaches targeting the GBA to ameliorate NDDs.

The effects of pomegranate consumption on inflammatory and oxidative stress biomarkers in adults: a systematic review and meta-analysis

BACKGROUND

Several studies have shown the effects of pomegranate on oxidative stress and inflammation biomarkers, while some studies showed no effects of pomegranate on these biomarkers. Therefore, we aimed to evaluate the effects of pomegranate consumption on C-reactive protein (CRP), interlukin-6 (IL-6), tumor necrosis factor α (TNF-α), total antioxidant capacity (TAC), and malondialdehyde (MDA) in adults.

METHODS

A systematic literature search was performed using databases, including PubMed, Web of Science, and Scopus, up to May 2023 to identify eligible randomized controlled trials (RCTs). Heterogeneity tests of the included trials were performed using the I2 statistic. Random effects models were assessed based on the heterogeneity tests, and pooled data were determined as the weighted mean difference with a 95% confidence interval.

RESULTS

Of 3811 records, 33 eligible RCTs were included in the current study. Our meta-analysis of the pooled findings showed that pomegranate consumption significantly reduced CRP (WMD: -0.50 mg/l; 95% CI -0.79 to -0.20; p = 0.001), IL-6 (WMD: -1.24 ng/L 95% CI -1.95 to -0.54; p = 0.001), TNF-α (WMD: -1.96 pg/ml 95%CI -2.75 to -1.18; p < 0.001), and MDA (WMD: -0.34 nmol/ml 95%CI -0.42 to -0.25; p < 0.001). Pooled analysis of 13 trials revealed that pomegranate consumption led to a significant increase in TAC (WMD: 0.26 mmol/L 95%CI 0.03 to 0.49; p = 0.025).

CONCLUSION

Overall, the results demonstrated that pomegranate consumption has beneficial effects on oxidative stress and inflammatory biomarkers in adults. Therefore, pomegranate can be consumed as an effective dietary approach to attenuate oxidative stress and inflammation in patients with cardiovascular diseases.

PROSPERO REGISTRATION CODE

CRD42023406684.

Combined impacts of microplastics and cadmium on the liver function, immune response, and intestinal microbiota of crucian carp (Carassius carassius)

Microplastics (MPs) and the heavy metal cadmium (Cd) have attracted global attention for their toxicological interactions in aquatic organisms. The purpose of this investigation was evaluating the effect of MPs (1 mg L^-1) and Cd (5 mg L^-1) on the liver function, immune response of crucian carp (Carassius carassius) after 96 h exposure, and intestinal microbiota after 21 days, respectively. Co-exposure to MPs and Cd significantly enhanced MP accumulation in the liver of the crucian carp compared to the accumulation with exposure to MPs alone. Co-exposure to MPs and Cd triggered notable histopathological alterations accompanied by increased hepatic cell necrosis and inflammation, and was associated with higher aspartate aminotransferase and alanine aminotransferase levels, lower superoxide dismutase and catalase activity levels, but higher malondialdehyde content and total antioxidant capacity in the liver. Moreover, the combined treatment of MPs and Cd led to the up-regulated transcription of genes related to immune response, such as interleukin 8 (il-8), il-10, il-1β, tumor necrosis factor-α, and heat shock protein 70, both in the liver and spleen. Co-exposure to MPs and Cd reduced the variety and abundance of the intestinal microbiota in the crucian carp. Our research indicates that the combined exposure to MPs and Cd may exert synergistic toxic effects on crucian carp, which could impede the sustainable growth of the aquaculture industry and pose potential risks to food safety.

Advanced Delivery System of Polyphenols for Effective Cancer Prevention and Therapy

Polyphenols from plants such as fruits and vegetables are phytochemicals with physiological and pharmacological activity as potential drugs to modulate oxidative stress and inflammation associated with cardiovascular disease, chronic disease, and cancer. However, due to the limited water solubility and bioavailability of many natural compounds, their pharmacological applications have been limited. Researchers have made progress in the development of nano- and micro-carriers that can address these issues and facilitate effective drug delivery. The currently developed drug delivery systems maximize the fundamental effects in various aspects such as absorption rate, stability, cellular absorption, and bioactivity of polyphenols. This review focuses on the antioxidant and anti-inflammatory effects of polyphenols enhanced by the introduction of drug delivery systems, and ultimately discusses the inhibition of cancer cell proliferation, growth, and angiogenesis.

Decoding the neurocircuitry of gut feelings: Region-specific microbiome-mediated brain alterations

Research in the last decade has unveiled a crucial role for the trillions of microorganisms that reside in the gut in influencing host neurodevelopment across the lifespan via the microbiota-gut-brain axis. Studies have linked alterations in the composition, complexity, and diversity of the gut microbiota to changes in behaviour including abnormal social interactions, cognitive deficits, and anxiety- and depressive-like phenotypes. Moreover, the microbiota has been linked with neurodevelopmental, neuropsychiatric, and neurodegenerative disorders. Interestingly, there appears to be specific brain regions governing the neurocircuitry driving higher cognitive function that are susceptible to influence from manipulations to the host microbiome. This review will aim to elucidate the region-specific effects mediated by the gut microbiota, with a focus on translational animal models and some existing human neuroimaging data. Compelling preclinical evidence suggests disruption to normal microbiota-gut-brain signalling can have detrimental effects on the prefrontal cortex, amygdala, hippocampus, hypothalamus, and striatum. Furthermore, human neuroimaging studies have unveiled a role for the microbiota in mediating functional connectivity and structure of specific brain regions that can be traced back to neurocognition and behavioural output. Understanding these microbiota-mediated changes will aid in identifying unique therapeutic targets for treating neurological disorders associated with these regions.

The Potential of Flavonoids and Flavonoid Metabolites in the Treatment of Neurodegenerative Pathology in Disorders of Cognitive Decline

Flavonoids are a biodiverse family of dietary compounds that have antioxidant, anti-inflammatory, antiviral, and antibacterial cell protective profiles. They have received considerable attention as potential therapeutic agents in biomedicine and have been widely used in traditional complimentary medicine for generations. Such complimentary medical herbal formulations are extremely complex mixtures of many pharmacologically active compounds that provide a therapeutic outcome through a network pharmacological effects of considerable complexity. Methods are emerging to determine the active components used in complimentary medicine and their therapeutic targets and to decipher the complexities of how network pharmacology provides such therapeutic effects. The gut microbiome has important roles to play in the generation of bioactive flavonoid metabolites retaining or exceeding the antioxidative and anti-inflammatory properties of the intact flavonoid and, in some cases, new antitumor and antineurodegenerative bioactivities. Certain food items have been identified with high prebiotic profiles suggesting that neutraceutical supplementation may be beneficially employed to preserve a healthy population of bacterial symbiont species and minimize the establishment of harmful pathogenic organisms. Gut health is an important consideration effecting the overall health and wellbeing of linked organ systems. Bioconversion of dietary flavonoid components in the gut generates therapeutic metabolites that can also be transported by the vagus nerve and systemic circulation to brain cell populations to exert a beneficial effect. This is particularly important in a number of neurological disorders (autism, bipolar disorder, AD, PD) characterized by effects on moods, resulting in depression and anxiety, impaired motor function, and long-term cognitive decline. Native flavonoids have many beneficial properties in the alleviation of inflammation in tissues, however, concerns have been raised that therapeutic levels of flavonoids may not be achieved, thus allowing them to display optimal therapeutic effects. Dietary manipulation and vagal stimulation have both yielded beneficial responses in the treatment of autism spectrum disorders, depression, and anxiety, establishing the vagal nerve as a route of communication in the gut-brain axis with established roles in disease intervention. While a number of native flavonoids are beneficial in the treatment of neurological disorders and are known to penetrate the blood–brain barrier, microbiome-generated flavonoid metabolites (e.g., protocatechuic acid, urolithins, γ-valerolactones), which retain the antioxidant and anti-inflammatory potency of the native flavonoid in addition to bioactive properties that promote mitochondrial health and cerebrovascular microcapillary function, should also be considered as potential biotherapeutic agents. Studies are warranted to experimentally examine the efficacy of flavonoid metabolites directly, as they emerge as novel therapeutic options.

Interlink between the gut microbiota and inflammation in the context of oxidative stress in Alzheimer's disease progression

The microbiota-gut-brain axis is an important pathway of communication and may dynamically contribute to Alzheimer's disease (AD) pathogenesis. Pathological commensal gut microbiota alterations, termed as dysbiosis, can influence intestinal permeability and break the blood-brain barrier which may trigger AD pathogenesis via redox signaling, neuronal, immune, and metabolic pathways. Dysbiosis increases the oxidative stress. Oxidants affect the innate immune system through recognizing microbial-derived pathogens by Toll-like receptors and initiating the inflammatory process. Most of the gut microbiome research work highlights the relationship between the gut microbiota and AD, but the contributory connection between precise bacteria and brain dysfunction in AD pathology cannot be fully demonstrated. Here, we summarize the current information of the fundamental connections between oxidative stress, inflammation, and gut dysbiosis in AD. This review emphasizes on the involvement of gut microbiota in the regulation of oxidative stress, inflammation, immune responses including central and peripheral cross-talk. It provides insights for novel preventative and therapeutic approaches in AD.

Research trend of microbiota-gut-brain axis in Alzheimer’s disease based on CiteSpace (2012–2021): A bibliometrics analysis of 608 articles

Background

Recently, research on the microbiota-gut-brain axis (MGBA) has received increasing attention, and the number of studies related to Alzheimer’s disease (AD) has increased rapidly, but there is currently a lack of summary of MGBA in AD.

Objective

To capture research hotspots, grasp the context of disciplinary research, and explore future research development directions.

Methods

In the core dataset of Web of Science, documents are searched according to specific subject words. CiteSpace software is used to perform statistical analysis on measurement indicators such as the number of published papers, publishing countries, institutions, subject areas, authors, cocited journals, and keywords, and to visualize of a network of relevant content elements.

Results

The research of MGBA in AD has shown an upward trend year by year, and the cooperation between countries is relatively close, and mainly involves the intersection of neuroscience, pharmacy, and microbiology. This research focuses on the relationship between MGBA and AD symptoms. Keyword hotspots are closely related to new technologies. Alzheimer’s disease, anterior cingulate cortex, inflammatory degeneration, dysbiosis, and other research are the focus of this field.

Conclusion

The study revealed that the research and development of MGBA in AD rapidly progressed, but no breakthrough has been made in the past decade, it still needs to be closely combined with multidisciplinary technology to grasp the frontier hotspots. Countries should further strengthen cooperation, improve the disciplinary system, and increase the proportion of empirical research in all research.

Selenium Nanoparticles-Enriched Lactobacillus casei ATCC 393 Prevents Cognitive Dysfunction in Mice Through Modulating Microbiota-Gut-Brain Axis

Purpose

The bidirectional communication between the gut and the central nervous system mediated by gut microbiota is closely related to the occurrence and development of neurodegenerative diseases, including Alzheimer's disease (AD). Selenium (Se) has been identified as playing a role against AD. Probiotics have beneficial effects on host brain function and behavior by modulating the microbiota-gut-brain axis. Herein, we evaluated the protective effects of Lactobacillus casei ATCC 393 (L. casei ATCC 393) and selenium nanoparticles-enriched L. casei ATCC 393 (L. casei ATCC 393-SeNPs) against D-galactose/aluminum chloride-induced AD model mice.

Methods

The Morris Water Maze (MWM) test was used to assess cognitive function of mice. The morphology and histopathological changes, antioxidant capacity and immune responses in the brain and ileum were evaluated. The alterations in intestinal permeability of the mice were determined using FITC-dextran. Gut microbiota composition was assessed using 16s rRNA sequencing.

Results

Thirteen weeks intervention with L. casei ATCC 393 or L. casei ATCC 393-SeNPs significantly improved cognitive dysfunction, and minimized amyloid beta (Aβ) aggregation, hyperphosphorylation of TAU protein, and prevented neuronal death by modulating Akt/cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathway. Moreover, compared with L. casei ATCC 393, L. casei ATCC 393-SeNPs further effectively mitigated intestinal barrier dysfunction by improving antioxidant capacity, regulating immune response, restoring gut microbiota balance, and increasing the level of short-chain fatty acids and neurotransmitters, thereby inhibiting the activation of microglia and protecting brain neurons from neurotoxicity such as oxidative stress and neuroinflammation.

Conclusion

These findings indicated that targeting the microbiota-gut-brain axis with L. casei ATCC 393-SeNPs may have therapeutic potential for the deficits of cognitive function in the AD model mice. Thus, we anticipate that L. casei ATCC 393-SeNPs may be a promising and safe Se nutritional supplement for use as a food additive to prevent the neurodegenerative disease.

Polyphenols–Gut–Heart: An Impactful Relationship to Improve Cardiovascular Diseases

A healthy gut provides the perfect habitat for trillions of bacteria, called the intestinal microbiota, which is greatly responsive to the long-term diet; it exists in a symbiotic relationship with the host and provides circulating metabolites, hormones, and cytokines necessary for human metabolism. The gut–heart axis is a novel emerging concept based on the accumulating evidence that a perturbed gut microbiota, called dysbiosis, plays a role as a risk factor in the pathogenesis of cardiovascular disease. Consequently, recovery of the gut microbiota composition and function could represent a potential new avenue for improving patient outcomes. Despite their low absorption, preclinical evidence indicates that polyphenols and their metabolites are transformed by intestinal bacteria and halt detrimental microbes’ colonization in the host. Moreover, their metabolites are potentially effective in human health due to antioxidant, anti-inflammatory, and anti-cancer effects. The aim of this review is to provide an overview of the causal role of gut dysbiosis in the pathogenesis of atherosclerosis, hypertension, and heart failure; to discuss the beneficial effects of polyphenols on the intestinal microbiota, and to hypothesize polyphenols or their derivatives as an opportunity to prevent and treat cardiovascular diseases by shaping gut eubiosis.

Emotional and Spontaneous Locomotor Behaviors Related to cerebellar Daidzein-dependent TrkB Expression Changes in Obese Hamsters

Current evidence supports the beneficial role of phytoestrogens in metabolic diseases, but their influences on spontaneous motor and anxiety behaviors plus neuroprotective effects have still not been completely elucidated. With the present study, neuro-behavioral activities were correlated to daidzein (DZ)-dependent expression changes of a high affinity catalytic receptor for several neurotrophins, and namely tropomyosin-related kinase B receptor (TrkB) in the cerebellar cortex of high-fat diet (HFD) hamsters (Mesocricetus auratus). Indeed, these changes appear to be tightly linked to altered plasma lipid profiles as shown by reduced low-density lipoproteins plus total cholesterol levels in DZ-treated obesity hamsters accounting for increased spontaneous locomotor together with diminished anxiety activities in novel cage (NCT) and light/dark box (LDT) tests. For this latter case, the anxiolytic-like hamsters spent more time in the light compartment, which was retained the aversive area of the LDT box. As for the evaluation of the neurotrophin receptor site, significantly elevated TrkB levels were also detected, for the first time, in the cerebellum of obese hamsters treated with DZ. In this condition, such a treatment widely led to an overall improvement of HFD-induced neurodegeneration damages, above all in the Purkinje and granular layers of the cerebellum. In this context, the notably active TrkB signaling events occurring in a DZ-dependent manner may turn out to be a key neuroprotective element capable of restoring normal emotional and spontaneously linked locomotor behaviors regulated by cerebellar cortical areas especially in obesity-related conditions.

Effect of Fermentation on the Bioactive Compounds of the Black Soybean and Their Anti-Alzheimer’s Activity

Black soybean is one of the nutritious crops and is being used in traditional medicines in Asian countries. In the present study, we fermented black soybean and screened against in vitro Alzheimer’s disease (AD) biomarkers such as cholinesterase enzymes, inflammatory factors, oxidative stress, and presence of γ-aminobutyric acid (GABA) levels. Firstly, we fermented black soybean with different lactic acid bacteria (LABs) and selected the Pediococcus acidilactici as the best LAB on the basis of GABA levels in the fermentate. We have found that black soybean fermented with P. acidilactici significantly inhibited the inflammatory factors (proteinase, protein denaturation, and lipoxygenase) and cholinesterase enzymes than non-fermented samples. An increase in the antioxidant capacity (FRAP, ABTS, and DPPH), anthocyanins, phenolics, flavonoids, and GABA content was also observed in fermented samples. Moreover, UHPLC-ESI-QTOF-MS/MS technique identified 38 bioactive components, including polyphenols, amino acids, and fatty acids. Among identified components, eight bioactive compounds were quantified, and an increase in the concentration of daidzein, genistein, glycitein, (+)-catechin, quercetin, and gallic acid was observed in fermented samples. However, the concentration of rutin and soyasaponin was higher in raw samples. These results indicated that fermentation of black soybean with P. acidilactici is a promising approach that can be used to develop functional foods to inhibit/prevent AD and other neurodegenerative diseases.

Effect of Ginseng Powder Supplementation on the Physicochemical Properties, Antioxidant Capacity, and Sensory Characteristics of Cream Soup

Ginseng has been used as a medicinal herb in Asian countries for hundreds of years. It contains many kinds of ginsenosides as major active ingredients and is known to have neuroprotective, anti-inflammatory, antitumor, and antidiabetic properties. In this study, we have developed cream soup with different concentrations (0%, 3%, 5%, 7%, and 10%) of ginseng powder (GP) and determined the quality characteristics (color, viscosity, salinity, etc.) and antioxidant activity, along with sensory parameters. After the addition of GP, significant differences in salinity, L* and a*color value, DPPH, and ABTS were found among different concentrations of GP. Cream soup supplemented with GP 10% exhibited the highest values for DPPH and ABTS (83.5% and 87%, respectively), while the contents of total phenolic and saponin were 0.651 ± 0.02 (mg Gallic acid Equiv./g, DW) and 0.797 ± 0.05 (mg Diosgenin Equiv./g, DW), respectively. Moreover, there were no significant changes for °Brix value, pH, acidity, and total flavonoids content compared to control. The sensory characteristics indicated bitterness with the increase in the concentration of GP. However, a non-significant difference was observed between the control and supplemented samples for color, viscosity, and overall preference. Therefore, the supplementation of GP to cream soup could exhibit health benefits and increase the demand for ginseng to promote public health as functional food material.

Comprehensive profiling of bioactive compounds in germinated black soybeans via UHPLC-ESI-QTOF-MS/MS and their anti-Alzheimer's activity

Black soybeans contain several bioactive compounds and commonly consumed due to their health-related activities but rarely cultivated as edible sprouts. The present study investigated the changes that occurred during germination in two new genotypes black soybeans. Raw and germinated seeds were tested against in vitro Alzheimer's disease (AD) biomarkers, including oxidative stress, inflammatory factors and cholinesterase enzymes as well as γ-aminobutyric acid (GABA) levels. Sprouts significantly inhibited the cholinesterase enzymes and inflammatory factors (protein denaturation, proteinase and lipoxygenase) than seeds. An increase in phenolic, flavonoid and GABA (10-folds) content and antioxidant capacity (ABTS, DPPH, and FRAP) was observed in germinated seeds. However, anthocyanin content was decreased in sprouts. UHPLC-ESI-QTOF-MS2 metabolites profiling approach identified 22 compounds including amino acids, peptides, fatty acids, and polyphenols. Among identified compounds, daidzein, genistein, gallic acid, spermidine, L-asparagine, and L-lysine exhibited the highest increase after germination. The current study reveals that germination of black soybeans have promising potential to inhibit/prevent AD and can be used to develop functional foods.

Effects of Natural Polyphenols on Oxidative Stress-Mediated Blood–Brain Barrier Dysfunction

The blood-brain barrier (BBB), which consists mainly of brain microvascular endothelial cells and astrocytes connected by tight junctions (TJs) and adhesion molecules (AMs), maintains the homeostatic balance between brain parenchyma and extracellular fluid. Accumulating evidence shows that BBB dysfunction is a common feature of neurodegenerative diseases, including stroke, traumatic brain injury, and Alzheimer’s disease. Among the various pathological pathways of BBB dysfunction, reactive oxygen species (ROS) are known to play a key role in inducing BBB disruption mediated via TJ modification, AM induction, cytoskeletal reorganization, and matrix metalloproteinase activation. Thus, antioxidants have been suggested to exert beneficial effects on BBB dysfunction-associated brain diseases. In this review, we summarized the sources of ROS production in multiple cells that constitute or surround the BBB, such as BBB endothelial cells, astrocytes, microglia, and neutrophils. We also reviewed various pathological mechanisms by which BBB disruption is caused by ROS in these cells. Finally, we summarized the effects of various natural polyphenols on BBB dysfunction to suggest a therapeutic strategy for BBB disruption-related brain diseases.