Neuroprotective effects of green and black teas and their catechin gallate esters against β-amyloid-induced toxicity

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.

Effect of cycloastragenol and punicalagin on Prp(106-126) and Aβ(25-35) oligomerization and fibrillizaton

Numerous neurological disorders, including prion, Parkinson's, and Alzheimer's disease (AD), are identified as being caused by alterations in protein conformation, aggregation, and metal ion dyshomeostasis. Recent years have seen a significant increase in the exploration and study of natural products (NPs) from plant and microbial sources for their therapeutic potential against several diseases, including cancer, diabetes, cardiovascular disease, and neurodegenerative diseases. In this study, we have examined the effect of two NPs, cycloastragenol (CAG) and punicalagin (PCG), on the metal-induced oligomerization and aggregation of Aβ25-35 and PrP106-126 peptides. The peptide aggregation and inhibitory properties of both NPs were examined by the thioflavin-T (ThT) assay, MALDI-TOF, circular dichroism (CD) spectroscopy, and transmission electron microscopy (TEM). Among the two NPs, PCG significantly binds to the peptides, chelates metal ions (Cu2+ and Zn2+), inhibits peptide aggregation, substantially reduces oxidative stress, and controls the production of reactive oxygen species (ROS). Both NPs exhibited low cytotoxicity and prominently mitigated peptide-mediated cell cytotoxicity in hippocampal neuronal HT-22 cells by covalent bonding and hydrophobic interactions.

Correlation between total phenolic and flavonoid contents and biological activities of 12 ethanolic extracts of Iranian propolis

Propolis is a resinous substance produced by honey bees that is very popular as a natural remedy in traditional medicine. The current research is the first study on the biological properties of ethanolic extracts of propolis (EEP) from several different regions (12) of Iran. Total phenolic and flavonoid contents (TPC and TFC) of Iranian EEPs were variable between 26.59-221.38 mg GAE/g EEP and 4.8-100.03 mg QE/g EEP. The DPPH scavenging assay showed all the studied EEP samples, except for the sample with the lowest TPC and TFC (P6), have suitable antioxidant activity. All the EEPs inhibited both cholinesterase enzymes (acetylcholinesterase: AChE, butyrylcholinesterase: BuChE) but most of them exhibited a distinct selectivity over BuChE. Evaluation of the antibacterial activity of the EEP samples using four pathogenic bacteria (B. cereus, S. aureus, A. baumannii, and P. aeruginosa) demonstrated that the antibacterial properties of propolis are more effective on the gram-positive bacterium. Spearman correlation analysis showed a strong positive correlation between TPC and TFC of the Iranian EEPs and their antioxidant, anticholinesterase, and antibacterial activities. Considering that there is ample evidence of anticholinesterase activity of flavonoids and a significant correlation between the anticholinesterase activity of the studied Iranian EEPs and their total flavonoid content was observed, the interaction of 17 well-known propolis flavonoids with AChE and BuChE was explored using molecular docking. The results indicated that all the flavonoids interact with the active site gorge of both enzymes with high affinity. Summing up, the obtained results suggest that Iranian propolis possesses great potential for further studies.

Protective Effects of Cirsium japonicum var. maackii Flower on Amyloid Beta25-35-Treated C6 Glial Cells

Amyloid beta (Aβ) is a neurotoxic peptide and a key factor causing Alzheimer's disease. Cirsium japonicum var. maackii (CJM) has neuroprotective effects, but the protective effects of the flower from CJM (FCJM) on the neural system remain unclear. This study aimed to identify the fraction of FCJM with the highest neuroprotective potential and investigate its protective mechanisms against Aβ_25-35-induced inflammation in C6 glial cells. The cell viability and generation of reactive oxygen species (ROS) were measured to investigate the positive effect of FCJM on oxidative stress. Treatment with the FCJM extract or fractions increased the cell viability to 60-70% compared with 52% in the Aβ_25-35-treated control group and decreased ROS production to 84% compared with 100% in the control group. The ethyl acetate fraction of FCJM (EFCJM) was the most effective among all the extracts and fractions. We analyzed the protective mechanisms of EFCJM on Aβ_25-35-induced inflammation in C6 glial cells using Western blot. EFCJM downregulated amyloidogenic pathway-related proteins, such as Aβ precursor protein, β-secretase, presenilin 1, and presenilin 2. Moreover, EFCJM attenuated the Bax/Bcl-2 ratio, an index of apoptosis, and upregulated the oxidative stress-related protein, heme oxygenase-1. Therefore, this study demonstrated that FCJM improves cell viability and inhibits ROS in Aβ_25-35-treated C6 glial cells. Furthermore, EFCJM exhibits neuroprotective effects in Aβ_25-35-induced inflammation in C6 glial cells by modulating oxidative stress and amyloidogenic and apoptosis signaling pathways. FCJM, especially EFCJM, can be a promising agent for neurodegenerative disease prevention.

Effects of Gallic Acid on Memory Deficits and Electrophysiological Impairments Induced by Cerebral Ischemia/Reperfusion in Rats Following Exposure to Ambient Dust Storm

We aimed to investigate the probable protective effects of gallic acid (GA) on cognitive deficits, hippocampal long term potentiation (LTP) impairments, and molecular changes induced by cerebral ischemia/reperfusion (I/R) in rats following exposure to ambient dust storm. After pretreatment with GA (100 mg/kg), or vehicle (Veh) (normal saline, 2 ml/kg) for ten days, and 60 minutes' exposure to dust storm including PM (PM, 2000-8000 g/m3) every day, 4-vessel occlusion (4VO) type of I/R was induced. Three days after I/R induction, we evaluated behavioral, electrophysiological, histopathological, molecular and brain tissue inflammatory cytokine changes. Our findings indicated that pretreatment with GA significantly reduced cognitive impairments caused by I/R (P < 0.05) and hippocampal LTP impairments caused by I/R after PM exposure (P < 0.001). Additionally, after exposure to PM, I/R significantly elevated the tumor necrosis factor α content (P < 0.01) and miR-124 level (P < 0.001) while pre-treatment with GA reduced the level of miR-124 (P < 0.001). Histopathological results also revealed that I/R and PM caused cell death in the hippocampus CA1 area (P < 0.001) and that GA decreased the rate of cell death (P < 0.001). Our findings show that GA can prevent brain inflammation, and thus cognitive and LTP deficits caused by I/R, PM exposure, or both.

The Effect of Ethanol Extract from Mesua ferrea Linn Flower on Alzheimer's Disease and Its Underlying Mechanism

The effects of Mesua ferrea Linn flower (MFE) extract on the pathogenic cascade of Alzheimer's disease (AD) were determined by an in vitro and cell culture model in the search for a potential candidate for the treatment of AD. The 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay exhibited that the MFE extract had antioxidant activities. According to the Ellman and the thioflavin T method's result, the extracts could inhibit acetylcholinesterase and β-amyloid (Aβ) aggregation. Studies on neuroprotection in cell culture found that the MFE extract could reduce the death of human neuroblastoma cells (SH-SY5Y) caused by H₂O₂ and Aβ. Western blot analysis exhibited that the MFE extract alleviated H₂O₂-induced neuronal cell damage by downregulating the pro-apoptotic proteins, including cleaved caspase-3, Bax, and by enhancing the expression of anti-apoptotic markers including MCl₁, BCl_xl, and survivin. Moreover, MFE extract inhibited the expression of APP, presenilin 1, and BACE, and increased the expression of neprilysin. In addition, the MFE extract could enhance scopolamine-induced memory deficit in mice. Overall, results showed that the MFE extract had several modes of action related to the AD pathogenesis cascade, including antioxidants, anti-acetylcholinesterase, anti-Aβ aggregation, and neuroprotection against oxidative stress and Aβ. Therefore, the M. ferrea L. flower might be a possibility for further development as a medication for AD.

Computer-Aided Screening and Revealing Action Mechanism of Green Tea Polyphenols Intervention in Alzheimer's Disease

The accumulation of cross-β-sheet amyloid fibrils is a hallmark of the neurodegenerative process of Alzheimer's disease (AD). Although it has been reported that green tea substances such as epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC) and epigallocatechin-3-gallate (EGCG) could alleviate the symptoms of AD and other neurodegenerative diseases, the pharmacological mechanism remains largely unexplored. This study aimed to reveal the underlying mechanism of EC, ECG, EGC and EGCG in AD using a computer-aided screening strategy. Our results showed that the four tea polyphenols interfered with the signaling pathways of AD via calcium signaling channels, neurodegeneration-multiple disease signal pathways and others. We also identified the key residues of the interaction between VEGFA and the four active components, which included Glu64 and Phe36. Overall, we have provided valuable insights into the molecular mechanism of tea polyphenols, which could be used as a reference to improve therapeutic strategies against AD.

The therapeutic potential of matcha tea: A critical review on human and animal studies

Matcha is a powdered form of Japanese green tea that has been gaining global popularity recently. Matcha tea has various health benefits, including an enhancing effect on cognitive function, cardio-metabolic health, and anti-tumorogenesis. To date, randomized clinical trials (RCT) showed that matcha decreases stress, slightly enhances attention and memory, and has no effect on mood. Results regarding the effect of matcha on cognitive function are contradictory and more RCTs are warranted. The cardio-metabolic effects of matcha have only been studied in animals, but findings were more homogenous. Consuming matcha with a high-fat diet resulted in decreased weight gain velocity, food intake, improved serum glucose and lipid profile, reduced inflammatory cytokines and ameliorated oxidative stress. Evidence regarding the anti-tumor function of matcha is very limited. Findings showed that matcha can affect proliferation, viability, antioxidant response, and cell cycle regulation of breast cancer cells. Nonetheless, more studies are needed to examine this effect on different types of cancer cells, and there is also a need to verify it using animal models. Overall, the evidence regarding the effect of matcha tea on cognitive function, cardio-metabolic function, and anti-tumor role is still limited, and conclusions cannot be drawn.

Using mass spectrometry-based methods to understand amyloid formation and inhibition of alpha-synuclein and amyloid beta

Amyloid fibrils, insoluble β-sheets structures that arise from protein misfolding, are associated with several neurodegenerative disorders. Many small molecules have been investigated to prevent amyloid fibrils from forming; however, there are currently no therapeutics to combat these diseases. Mass spectrometry (MS) is proving to be effective for studying the high order structure (HOS) of aggregating proteins and for determining structural changes accompanying protein-inhibitor interactions. When combined with native MS (nMS), gas-phase ion mobility, protein footprinting, and chemical cross-linking, MS can afford regional and sometimes amino acid spatial resolution of the aggregating protein. The spatial resolution is greater than typical low-resolution spectroscopic, calorimetric, and the traditional ThT fluorescence methods used in amyloid research today. High-resolution approaches can struggle when investigating protein aggregation, as the proteins exist as complex oligomeric mixtures of many sizes and several conformations or polymorphs. Thus, MS is positioned to complement both high- and low-resolution approaches to studying amyloid fibril formation and protein-inhibitor interactions. This review covers basics in MS paired with ion mobility, continuous hydrogen-deuterium exchange (continuous HDX), pulsed hydrogen-deuterium exchange (pulsed HDX), fast photochemical oxidation of proteins (FPOP) and other irreversible labeling methods, and chemical cross-linking. We then review the applications of these approaches to studying amyloid-prone proteins with a focus on amyloid beta and alpha-synuclein. Another focus is the determination of protein-inhibitor interactions. The expectation is that MS will bring new insights to amyloid formation and thereby play an important role to prevent their formation.

Biological Role of Nutrients, Food and Dietary Patterns in the Prevention and Clinical Management of Major Depressive Disorder

Major Depressive Disorder (MDD) is a growing disabling condition affecting around 280 million people worldwide. This complex entity is the result of the interplay between biological, psychological, and sociocultural factors, and compelling evidence suggests that MDD can be considered a disease that occurs as a consequence of an evolutionary mismatch and unhealthy lifestyle habits. In this context, diet is one of the core pillars of health, influencing multiple biological processes in the brain and the entire body. It seems that there is a bidirectional relationship between MDD and malnutrition, and depressed individuals often lack certain critical nutrients along with an aberrant dietary pattern. Thus, dietary interventions are one of the most promising tools to explore in the field of MDD, as there are a specific group of nutrients (i.e., omega 3, vitamins, polyphenols, and caffeine), foods (fish, nuts, seeds fruits, vegetables, coffee/tea, and fermented products) or dietary supplements (such as S-adenosylmethionine, acetyl carnitine, creatine, amino acids, etc.), which are being currently studied. Likewise, the entire nutritional context and the dietary pattern seem to be another potential area of study, and some strategies such as the Mediterranean diet have demonstrated some relevant benefits in patients with MDD; although, further efforts are still needed. In the present work, we will explore the state-of-the-art diet in the prevention and clinical support of MDD, focusing on the biological properties of its main nutrients, foods, and dietary patterns and their possible implications for these patients.

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.

Linking Alzheimer’s Disease and Type 2 Diabetes: Characterization and Inhibition of Cytotoxic Aβ and IAPP Hetero-Aggregates

The cytotoxic self-aggregation of β-amyloid (Aβ) peptide and islet amyloid polypeptide (IAPP) is implicated in the pathogenesis of Alzheimer’s disease (AD) and Type 2 diabetes (T2D), respectively. Increasing evidence, particularly the co-deposition of Aβ and IAPP in both brain and pancreatic tissues, suggests that Aβ and IAPP cross-interaction may be responsible for a pathological link between AD and T2D. Here, we examined the nature of IAPP-Aβ40 co-aggregation and its inhibition by small molecules. In specific, we characterized the kinetic profiles, morphologies, secondary structures and toxicities of IAPP-Aβ40 hetero-assemblies and compared them to those formed by their homo-assemblies. We demonstrated that monomeric IAPP and Aβ40 form stable hetero-dimers and hetero-assemblies that further aggregate into β-sheet-rich hetero-aggregates that are toxic (cell viability <50%) to both PC-12 cells, a neuronal cell model, and RIN-m5F cells, a pancreatic cell model for β-cells. We then selected polyphenolic candidates to inhibit IAPP or Aβ40 self-aggregation and examined the inhibitory effect of the most potent candidate on IAPP-Aβ40 co-aggregation. We demonstrated that epigallocatechin gallate (EGCG) form inter-molecular hydrogen bonds with each of IAPP and Aβ40. We also showed that EGCG reduced hetero-aggregate formation and resulted in lower β-sheets content and higher unordered structures in IAPP-Aβ40-EGCG samples. Importantly, we showed that EGCG is highly effective in reducing the toxicity of IAPP-Aβ40 hetero-aggregates on both cell models, specifically at concentrations that are equivalent to or are 2.5-fold higher than the mixed peptide concentrations. To the best of our knowledge, this is the first study to report the inhibition of IAPP-Aβ40 co-aggregation by small molecules. We conclude that EGCG is a promising candidate to prevent co-aggregation and cytotoxicity of IAPP-Aβ40, which in turn, contribute to the pathological link between AD and T2D.

Interaction Between Diet and Microbiota in the Pathophysiology of Alzheimer's Disease: Focus on Polyphenols and Dietary Fibers

Animal studies increasingly indicate that the gut microbiota composition and function can be involved in the pathophysiology and progression of Alzheimer's disease (AD) at multiple levels. However, few studies have investigated this putative gut-brain axis in human beings, and none of them considered diet as a determinant of intestinal microbiota composition. Epidemiological studies highlight that a high intake of fruit and vegetables, such as that typical of the Mediterranean diet, can modulate AD progression. Thus, nutritional interventions are being increasingly studied as a possible non-pharmacological strategy to slow down the progression of AD. In particular, polyphenols and fibers represent the nutritional compounds with the higher potential of counterbalancing the pathophysiological mechanisms of dementia due to their antioxidant, anti-inflammatory, and anti-apoptotic properties. These actions are mediated by the gut microbiota, that can transform polyphenols and fibers into biologically active compounds including, among others, phenyl-γ-valerolactones, urolithins, butyrate, and other short-chain fatty acids. In this review, the complex mechanisms linking nutrition, gut microbiota composition, and pathophysiology of cognitive decline in AD are discussed, with a particular focus on the role of polyphenols and fibers. The gaps between pre-clinical and clinical studies are particularly emphasized, as well as the urgent need for studies comprehensively evaluating the link between nutrition, microbiome, and clinical aspects of AD.

Effects of tannic acid in streptozotocin-induced sporadic Alzheimer's Disease: insights into memory, redox status, Na+, K+-ATPase and acetylcholinesterase activity

The aim of this study was to investigate the ability of tannic acid (TA) in preventing memory deficits and neurochemical alterations observed in a model for Sporadic Dementia of Alzheimer's Type. Rats were treated with TA (30 mg/kg) daily for 21 days, and subsequently received intracerebroventricular injection of streptozotocin (STZ). We observed that STZ induced learning and memory impairments; however, treatment with TA was able to prevent these effects. In cerebral cortex and hippocampus, STZ induced an increase in acetylcholinesterase activity, reduced Na⁺, K⁺-ATPase activity and induced oxidative stress increasing thiobarbituric acid-reactive substances, nitrites and reactive oxygen species levels and reducing the activity of antioxidant enzymes. Treatment with TA was able in prevent the major of these neurochemical alterations. In conclusion, TA prevented memory deficits, alterations in brain enzyme activities, and oxidative damage induced by STZ. Thus, TA can be an interesting strategy in the prevention of Sporadic Alzheimer's Disease.

Protective Effects of Green Tea Supplementation against Lead-Induced Neurotoxicity in Mice

The use of natural products as therapeutic agents is rapidly growing recently. In the current study, we investigated the protective effects of green tea supplementation on lead-induced toxicity in mice. Forty albino mice were divided into four groups as follows: A: control group; B: green tea receiving group; C: lead-intoxicated group; and D: lead-intoxicated group supplemented with green tea. At the end of the experiment, the animals were tested for neurobehavioral and biochemical alterations. Green tea was analyzed through Gas Chromatography–Mass Spectrometry (GC/MS) analysis. We found that supplementation with green tea ameliorated the lead-associated increase in body weight and blood glucose. Green tea supplementation also changed the blood picture that was affected due to lead toxicity and ameliorated lead-induced dyslipidemia. The group of mice that were supplemented with green tea has shown positive alterations in locomotory, anxiety, memory, and learning behaviors. The GC/MS analysis revealed many active ingredients among which the two most abundant were caffeine and 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester. We concluded that green tea supplementation has several positive effects on the lead-induced neurotoxicity in mice and that these effects may be attributed to its main two active ingredients.

Inhibition of Islet Amyloid Polypeptide Fibrillation by Structurally Diverse Phenolic Compounds and Fibril Disaggregation Potential of Rutin and Quercetin

The influence of 12 food-derived phenolic compounds on islet amyloid polypeptide (IAPP) fibrillation was investigated. Results from thioflavin T assay demonstrated that gallic acid, caffeic acid, and rutin and its aglycone, quercetin, inhibited IAPP fibrillation at 1:0.5, 1:1, and 1:2 IAPP-phenolic molar ratios. Circular dichroism and dynamic light scattering at the 1:1 IAPP-phenolic ratio confirmed the inhibition of fibril formation. Rutin and quercetin increased the lag time by 90 and 6%, and the relative α-helix content by 63 and 48%, respectively. Gallic acid decreased the elongation rate by 30%, whereas caffeic acid decreased the maximum fluorescence intensity by 65%. Furthermore, fluorescence microscopy and transmission electron microscopy (TEM) showed IAPP fibril morphologies indicative of fibrillation reduction by the compounds. Molecular docking and TEM showed that rutin and quercetin disaggregated preformed IAPP fibrils potentially through fibrillar-monomeric equilibrium shifts. These findings demonstrate important structural features of phenolic compounds for disaggregating IAPP fibrils or inhibiting their formation.

Understanding the Complex Interactions between Coffee, Tea Intake and Neurologically Relevant Tissues Proteins in the Development of Anxiety and Depression

OBJECTIVES

Coffee and tea intake might be associated with psychiatry diseases. However, it is unclear whether the effect of coffee/tea on anxiety and depression depending on the different types of proteins.

DESIGN

This was a cross-sectional study.

SETTING

Our datasets were downloaded from online.

PARTICIPANTS

Phenotypic and genotypic data for coffee intake(N=376,196) and tea intake (N=376,078) were derived from UK Biobank. GWAS data of proteins (N=1,537) from neurologically relevant tissues (brain, cerebrospinal fluid (CSF) and plasma) were obtained from a recently published study.

MEASUREMENTS

Multivariate linear analysis was then used to evaluate the potential interaction effect between coffee/tea intake and proteins polygenetic risk score (PRS) on the risks of anxiety and depression controlling for age, sex, Townsend deprivation index (TDI), smoke, drinking and education level.

RESULTS

34 coffee intake-proteins interactions and 15 tea intake-proteins interactions were observed in anxiety individuals, such as coffee intake-c-Jun interaction (β=0.0169, P=4.131×10-3), coffee intake-Fas interaction (β=-0.0190, P=8.132×10-4), tea intake-sL-Selectin interaction (β=0.0112, P=5.412×10-3) and tea intake-IL-1F6 (β=0.0083, P=4.471×10-2). 25 coffee intake-proteins and 14 tea intake-proteins interactions were observed in depression individuals, including coffee intake- IL-1 sRI (β=0.0171, P=4.888×10-3) and coffee intake-NXPH1 interaction (β=0.0156, P=9.819×10-3), tea intake-COLEC12 interaction (β=0.0127, P=3.280×10-3), and tea intake-Layilin interaction (β=0.0117, P=7.926×10-3).

CONCLUSIONS

Our results suggested the important role of multiple proteins in neurologically relevant tissues in the associations between coffee/tea intake and psychiatry diseases, providing entry points to explore the mechanisms underlying anxiety and depression.

Enhancement of Cluster Differentiation Antigen 4 and the Body Mass Index in Patients with HIV

&lt;b&gt;Background and Objective:&lt;/b&gt; The HIV is the virus that can cause AIDS by attacking white blood cells such as T cells CD4&lt;sup&gt;+&lt;/sup&gt;. This study aimed to determine the relationship between antiretroviral (ARV) drugs and supplements of black tea (&lt;i&gt;Camellia sinensis&lt;/i&gt; var. &lt;i&gt;assamica&lt;/i&gt;) powder to increase the CD4 and Body Mass Index (BMI) in patients with HIV. &lt;b&gt;Materials and Methods:&lt;/b&gt; This study used a quasi-experiment. From the average number of 10 patient visits every month in the period of January to March, 2021 in the outpatient clinic for patients diagnosed positive with HIV-AIDS, seventy patients were enlisted and divided into 2 groups from 12 districts, 35 groups intervention received ARV drugs and supplements steeping black tea powder form as much as 1,505 mg, equivalent to 5-7 glasses a 1,000-1,400 mL/day for 24 weeks, while the control group of patients received ARV drugs, standard diet each house and nutrition education. &lt;b&gt;Results:&lt;/b&gt; This study showed a BMI before the intervention control group's 1st week 19.31±2.17 and after the intervention for 24 weeks, a BMI of 18.78±2.42. CD4 levels before the intervention, the 1st week were 380.57±78.63 and after the intervention for 24 weeks, 365.74±81.13 in this case either BMI or CD4 did not experience significant improvements. While the intervention group before the intervention 1st week BMI was 21.61±3.32 and after the intervention for 24 weeks, 22.2±3.19 or increased significantly (p = 0.002) and the levels of CD4 in the 1st week before the intervention, 360.91±221.20 and after the intervention for 24 weeks, 425.14±178.87 or increased significantly (p = 0.003). &lt;b&gt;Conclusion:&lt;/b&gt; The ARV therapy and black tea powder significantly increased levels of CD4 and BMI HIV sufferers through the improvement of the status of T-cell immunity and body mass index.

Disentangling Mitochondria in Alzheimer's Disease

Alzheimer's disease (AD) is a major cause of dementia in older adults and is fast becoming a major societal and economic burden due to an increase in life expectancy. Age seems to be the major factor driving AD, and currently, only symptomatic treatments are available. AD has a complex etiology, although mitochondrial dysfunction, oxidative stress, inflammation, and metabolic abnormalities have been widely and deeply investigated as plausible mechanisms for its neuropathology. Aβ plaques and hyperphosphorylated tau aggregates, along with cognitive deficits and behavioral problems, are the hallmarks of the disease. Restoration of mitochondrial bioenergetics, prevention of oxidative stress, and diet and exercise seem to be effective in reducing Aβ and in ameliorating learning and memory problems. Many mitochondria-targeted antioxidants have been tested in AD and are currently in development. However, larger streamlined clinical studies are needed to provide hard evidence of benefits in AD. This review discusses the causative factors, as well as potential therapeutics employed in the treatment of AD.

Potential of Sorghum Polyphenols to Prevent and Treat Alzheimer's Disease: A Review Article

Alzheimer's disease (AD) is characterized by the excessive deposition of extracellular amyloid-beta peptide (Aβ) and the build-up of intracellular neurofibrillary tangles containing hyperphosphorylated tau proteins. This leads to neuronal damage, cell death and consequently results in memory and learning impairments leading to dementia. Although the exact cause of AD is not yet clear, numerous studies indicate that oxidative stress, inflammation, and mitochondrial dysfunction significantly contribute to its onset and progression. There is no effective therapeutic approach to stop the progression of AD and its associated symptoms. Thus, early intervention, preferably, pre-clinically when the brain is not significantly affected, is a better option for effective treatment. Natural polyphenols (PP) target multiple AD-related pathways such as protecting the brain from Aβ and tau neurotoxicity, ameliorating oxidative damage and mitochondrial dysfunction. Among natural products, the cereal crop sorghum has some unique features. It is one of the major global grain crops but in the developed world, it is primarily used as feed for farm animals. A broad range of PP, including phenolic acids, flavonoids, and condensed tannins are present in sorghum grain including some classes such as proanthocyanidins that are rarely found in others plants. Pigmented varieties of sorghum have the highest polyphenolic content and antioxidant activity which potentially makes their consumption beneficial for human health through different pathways such as oxidative stress reduction and thus the prevention and treatment of neurodegenerative diseases. This review summarizes the potential of sorghum PP to beneficially affect the neuropathology of AD.

Pharmacological actions and underlying mechanisms of Catechin: A review

BACKGROUND

Catechin is a phytochemical and is a major component of our daily use beverages, which has shown great potential in improving general health and fighting against several medical conditions. Clinical studies have confirmed its effectiveness in conditions ranging from acute upper respiratory tract infection, neuroprotection, to cardio-protection effects. Though most studies relate their potential to anti-oxidative action and radical scavenging action, still the mechanism of action is not clearly understood.

OBJECTIVE

The present review article is focused on addressing various pharmacological actions and underlying mechanisms of catechin. Additionally, we will try to figure out the major adverse effect and success in trials with catechin and lead to a conclusion for its effectiveness.

METHODS

This review article is based on the recent/ most cited papers of PubMed and Scopus databases.

DESCRIPTION

Catechin can regulate Nrf2 and NFkB pathways in ways that impact oxidative stress and inflammation by influencing gene expression. Other pathways like MAPKs and COMT and receptor tyrosine kinase are also affected by catechin and EGCG that alter their action and barge the cellular activity. This review article explored the structural aspect of catechin and its different isomers and analogs. It also evaluated its various therapeutic and pharmacological arrays .

CONCLUSION

Catechin and its stereo-isomers have shown their effectiveness as anti-inflammatory, anti-diabetic, anti-cancer, anti-neuroprotective, bactericidal, memory enhancer, anti-arthritis, and hepato-protective mainly through its activity to alter the pathway by NF-κB, Nrf-2, TLR4/NF-κB, COMT, and MAPKs.

Natural stereoisomeric flavonoids exhibit different disruptive effects and the mechanism of action on Aβ42 protofibril

Our simulations reveal that two enantiomeric catechins display a better disruptive effect on Aβ42 protofibril than their stereoisomer epicatechin. Unexpectedly, we find that catechins adopt both collapsed and extended states, while epicatechin populates only an extended state. Their different protofibril-disruptive effects are mostly attributed to the steric effect caused by the conformational differences.

Neuroprotective effects of oolong tea extracts against glutamate-induced toxicity in cultured neuronal cells and β-amyloid-induced toxicity in Caenorhabditis elegans

Oolong tea, a traditional Chinese tea, is especially popular in south China and has a variety of health benefits. However, studies about its neuroprotective and neuroregenerative properties are still limited. This study explored the neuroprotective and neurite outgrowth-promoting properties of oolong tea in cultured neuronal cells (Neuro-2a and HT22) and Caenorhabditis elegans models. Ultra performance liquid chromatography was applied to identify the main natural bioactive compounds in oolong tea. Using Neuro-2a and HT22 cells, we found that oolong tea extracts had a protective effect against glutamate-induced cell death. The extracts reduced intracellular reactive oxygen species accumulation and induced gene expression of cellular antioxidant enzymes such as GPx, GSTs and SODs. These extracts also increased the average neurite length, and GAP-43 and Ten-4 mRNA expression in Neuro-2a cells. Moreover, they had protective effects against Aβ-induced paralysis, chemotaxis deficiency and α-synuclein aggregation in C. elegans. This is the first study showing the neuroregenerative and neuroprotective potential of the oolong tea extracts against glutamate/Aβ/α-synuclein-induced toxicity in vitro and in vivo. Our study may support oolong tea extracts as potential candidates for the prevention of neurodegenerative diseases.

Role of natural plant products against Alzheimer's disease

Alzheimer's disease (AD) is one of the major neurodegenerative disorder. Deposition of amyloid fibrils and tau protein are associated with various pathological symptoms. Currently limited medication is available for AD treatment. Most of the drugs are basically cholinesterase inhibitors and associated with various side effects. Natural plant products have shown potential as a therapeutic agent for the treatment of AD symptoms. Variety of secondary metabolites like flavonoids, tannins, terpenoids, alkaloids and phenols are used to reduce the progression of the disease. Plant products have less or no side effect and are easily available. The present review gives a detailed account of the potential of natural plant products against the AD symptoms.

Green Tea, A Medicinal Food with Promising Neurological Benefits

Neurological disorders and their sequelae, as of the widespread and critical humans’ complications, affect the body's nervous systems, organ functions, and behaviors. According to WHO, neurological disorders are currently predicted to affect more than one billion people globally. It is well-established that complementary medicine is one of the high accepted interventions that could have been considered for the management of neurological ailments. The current review aimed to compile all the crucial data reporting the investigation on the conspicuous intervention of green tea (made of Camellia sinensis) and related lead compounds (especially l-theanine, epigallocatechin-3-gallate, epicatechin-3-gallate, epicatechin, and epigallocatechin) for their neurological activities, mechanisms of action, and clinical properties. According to the documents, green tea exhibits antidepressant, anti-neurodegenerative (e.g., anti-Parkinson and anti-Alzheimer), as well as neuroprotective effects.Chief among them, for offering novel work, it is worth focusing on several related assessments with great attention to more extensive standardized clinical trials, and subsequently more in-depth pharmacokinetic studies to safely introduce this beneficial medicinal food as a neuro-effective agent.

Healthy Drinks with Lovely Colors: Phenolic Compounds as Constituents of Functional Beverages

Consumers increasingly prefer and seek food and beverages, which, due to their natural characteristics, bring health benefits, both in the prevention of diseases and in their curative power. In this way, the production of nutraceutical foods and beverages gains more and more importance in the market. On the other hand, and because the eyes also eat, producing attractive foods due to their color, texture, appearance, and sensory characteristics is a permanent challenge in the food industry. Being able to gather healthy and attractive items in a single food is an even greater challenge. The long list of benefits associated with phenolic compounds, such as antioxidant, anticancer, anti-inflammatory, and antiaging properties, among others, fully justifies their use in the enrichment of various food products. Thus, in this review, we propose to summarize the potential use of phenolic compounds used as ingredients of pleasant and functional beverages.

Effects of Matcha Green Tea Powder on Cognitive Functions of Community-Dwelling Elderly Individuals

Matcha Green Tea Powder contains a variety of active ingredients beneficial to health, such as tea catechins, lutein and vitamin K. It is also known that these ingredients confer benefits upon cognitive functions of elderly people. Therefore, we aimed to investigate the relationship between a daily supplementation of Matcha and the change in cognitive functions of community-dwelling elderly people. A randomized, double-blind, placebo-controlled 12-week trial was performed. Sixty-one participants were recruited and randomly assigned to receive test drink containing 3 g powder from fresh Matcha or placebo powder per day. Changes in cognitive function were assessed utilizing a psychometric test battery. Daily food intake was assessed by a Brief-type Self-administered Diet History Questionnaire (BDHQ). In the gender-specific analysis, a significant cognitive enhancement was observed in the Montreal Cognitive Assessment (MoCA) score in the active group of women. In dietary analysis, we found a significant inverse correlation between consumption of vitamin K in daily diet, excluding test drinks, and change in MoCA. The present study suggests that daily supplementation of Matcha Green Tea Powder has protective effects against cognitive decline in community-dwelling elderly women.

Inhibition of Aβ aggregates in Alzheimer's disease by epigallocatechin and epicatechin-3-gallate from green tea

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive accumulation of senile plaques, which are primarily composed of misfolded amyloid β-peptide (Aβ). Aβ aggregates are believed to be a key factor in the pathogenesis of AD, affecting the nervous system in human body. The therapeutic potential of tea-derived polyphenolic compounds, (-)-epigallocatechin (EGC) and (-)-epicatechin-3-gallate (ECG), for AD was investigated by assessing their effects on the Cu²⁺/Zn²⁺-induced or self-assembled Aβ₄₀ aggregation using thioflavine T fluorescent spectrometry, inductively coupled plasma mass spectrometry, UV-Vis spectroscopy, transmission electron microscope, silver staining, immunohistochemistry, and immunofluorescence assays. EGC and ECG mildly bind to Cu²⁺ and Zn²⁺, and diminish the Cu²⁺- or Zn²⁺-induced or self-assembled Aβ aggregates; they also modulate the Cu²⁺/Zn²⁺-Aβ₄₀ induced neurotoxicity on mouse neuroblastoma Neuro-2a cells by reducing the production of ROS. Metal chelating, hydrogen bonding or Van Der Waals force may drive the interaction between the polyphenolic compounds and Aβ. The results demonstrate that green tea catechins EGC and ECG are able to alleviate the toxicity of Aβ oligomers and fibrils. Particularly, ECG can cross the blood-brain barrier to reduce the Aβ plaques in the brain of APP/PS1 mice, thereby protecting neurons from injuries. The results manifest the potential of green tea for preventing or ameliorating the symptoms of AD.

Gallic acid oxidation products alter the formation pathway of insulin amyloid fibrils

Amyloidogenic protein assembly into insoluble fibrillar aggregates is linked with several neurodegenerative disorders, such as Alzheimer’s or Parkinson’s disease, affecting millions of people worldwide. The search for a potential anti-amyloid drug has led to the discovery of hundreds of compounds, none of which have passed all clinical trials. Gallic acid has been shown to both modulate factors leading to the onset of neurodegenerative disorders, as well as directly inhibit amyloid formation. However, the conditions under which this effect is seen could lead to oxidation of this polyphenol, likely changing its properties. Here we examine the effect of gallic acid and its oxidised form on the aggregation of a model amyloidogenic protein–insulin at low pH conditions. We show a vastly higher inhibitory potential of the oxidised form, as well as an alteration in the aggregation pathway, leading to the formation of a specific fibril conformation.

Distinguishing the Effect on the Rate and Yield of Aβ42 Aggregation by Green Tea Polyphenol EGCG

Deposition of Aβ42 aggregates in the form of amyloid plaques is a pathological hallmark of Alzheimer's disease. A desired avenue of intervention is the inhibition of Aβ42 aggregation. Epigallocatechin gallate (EGCG), the main polyphenol in green tea, has been generally considered an inhibitor of Aβ aggregation. However, previous experiments focused on the reduction of the amount of Aβ42 aggregates, while the effect of EGCG on the rate of Aβ42 aggregation was not critically analyzed. Here we performed an experimental evaluation of Aβ42 aggregation kinetics in the absence and presence of EGCG at a wide range of concentrations. We found that EGCG reduced thioflavin T fluorescence in an EGCG concentration-dependent manner, suggesting that EGCG reduced the amount of Aβ42 fibrils. The effect of EGCG on the rate of Aβ42 aggregation appears to be bimodal. We found that higher EGCG-to-Aβ42 ratios promoted the rate of Aβ42 aggregation, while lower EGCG-to-Aβ42 ratios inhibited the aggregation rate. To confirm that the reduction of thioflavin T fluorescence is due to the lowered aggregate quantity, but not due to perturbation of thioflavin T binding to Aβ42 fibrils, we probed the effect of EGCG on Aβ42 aggregation using site-directed spin labeling. Electron paramagnetic resonance of spin-labeled Aβ42 aggregates suggests that high EGCG-to-Aβ42 ratios led to a greatly reduced amount of Aβ42 fibrils, and these aggregates adopt similar structures as the fibrils in the no-EGCG sample. Potential implications of this work in designing prevention or therapeutic strategies using EGCG are discussed.

Date palm (Phoenix dactylifera L.) fruit's polyphenols as potential inhibitors for human amylin fibril formation and toxicity in type 2 diabetes

BACKGROUND

β-Cell death is the key feature of type 2 diabetes mellitus (T2DM). The misfolding of human Islet Amyloid Polypeptide (hIAPP) is regarded as one of the causative factors of T2DM. Recent studies suggested that a diet based on date fruits presents various health benefits, as these fruits are naturally enriched in plant polyphenols.

METHOD

In this study, we used a broad biophysical approach, using cell biology techniques and bioinformatic tools, to demonstrate that various polyphenols from date palm (Phoenix dactylifera L.) fruit significantly inhibited hIAPP aggregation and cytotoxicity.

RESULT

Our results suggest that all of the polyphenols showed inhibitory effects, albeit varied, on the formation of toxic hIAPP amyloids. Correlation between cell viability assay, permeabilization of synthetic phospholipid vesicles tests, and ANS florescence measurements, revealed that both classes of polyphenols protected INS-1E cells from the toxicity of amylin aggregates. Docking results showed that the used polyphenols physically interacted with both hIAPP amyloidogenic region (residues Ser20-Ser29) and the non-amyloidogenic regions via hydrophobic and hydrogen interactions, thus reducing aggregation levels.

CONCLUSION

These findings highlight the benefits of consuming dates and the great potential of its polyphenols as a potential therapy for the prevention and treatment of T2DM as well as for many other amyloid-related diseases.

Catechins as Tools to Understand the Molecular Basis of Neurodegeneration

Protein misfolding as well as the subsequent self-association and deposition of amyloid aggregates is implicated in the progression of several neurodegenerative disorders including Alzheimer's and Parkinson's diseases. Modulators of amyloidogenic aggregation serve as essential tools to dissect the underlying molecular mechanisms and may offer insight on potential therapeutic solutions. These modulators include green tea catechins, which are potent inhibitors of amyloid aggregation. Although catechins often exhibit poor pharmacokinetic properties and bioavailability, they are still essential tools for identifying the drivers of amyloid aggregation and for developing other aggregation modulators through structural mimicry. As an illustration of such strategies, here we review how catechins have been used to map the toxic surfaces of oligomeric amyloid-like species and develop catechin-based phenolic compounds with enhanced anti-amyloid activity.

Amide derivatives of Gallic acid: Design, synthesis and evaluation of inhibitory activities against in vitro α-synuclein aggregation

Gallic acid (GA), a natural phenolic acid, has received numerous attention because of its anti-oxidative, anti-inflammatory, and anti-cancer activity. More importantly, GA can act as an efficient inhibitor of α-Synuclein (α-Syn) aggregation at early stages. Nevertheless, some evidences suggest that GA is unlikely to cross the blood-brain barrier because of its high hydrophilicity. Hence, GA may not be considered as a promising candidate or entering brain and directly affecting the central nervous system. Accordingly, we have designed and synthesized a series of amide derivatives of GA, some of which possess appropriate lipophilicity and hydrophilicity with LogP (2.09-2.79). Meanwhile, these sheet-like conjugated compounds have good π-electron delocalization and high ability of hydrogen-bond formation. Some compounds have shown better in vitro anti-aggregation activities than GA towards α-Syn, with IC₅₀ down to 0.98 μM. The valid modification strategy of GA is considered an efficient way to discover novel inhibitors of α-Syn aggregation.

Amyloid Aggregation of Insulin: An Interaction Study of Green Tea Constituents

Exogenous insulin, used as a therapeutic agent for diabetes, forms insoluble deposits containing amyloid fibrillar structures near the administration site. We have analyzed the in vitro anti-amyloid activity of four green tea constituents: (-)-epigallocatechin gallate (EGCG), (-)-epicatechin (EC), gallic acid (GA), caffeine (CF), and their equimolar mixtures. Regarding individually tested compounds, only EGCG inhibited the fibrillization process. The individual EC, GA, and CF molecules were ineffective. The presence of EGCG in equimolar combinations with GA, EC, or CF was required for the inhibitory activity of most mixtures. Molecular docking revealed that EGCG interacts with an essential amyloidogenic region of insulin chain B. Individually inactive GA had a potentiating effect on the activity of EGCG. In contrast, EC and CF had a negative impact on the activity of the mixtures. We have observed diverse morphology and the amount of insulin amyloid aggregates formed in the presence of studied compounds. The distinct types of amyloid aggregates created in vitro in the presence of EGCG and other green tea constituents were characterized. Results indicate that the biological activity of individual molecules is not directly applicable to the pooled samples effects prediction.

Vanillin and vanillic acid modulate antioxidant defense system via amelioration of metabolic complications linked to Fe2+-induced brain tissues damage

The therapeutic effect of phenolics on neurodegenerative diseases has been attributed to their potent antioxidant properties. In the present study, the neuroprotective activities of vanillin and vanillic acid were investigated in Fe²⁺- induced oxidative toxicity in brain tissues by investigating their therapeutic effects on oxidative imbalance, cholinergic and nucleotide-hydrolyzing enzymes activities, dysregulated metabolic pathways. Their cytotoxicity was investigated in hippocampal neuronal cell lines (HT22). The reduced glutathione level, SOD and catalase activities were ameliorated in tissues treated with the phenolics, with concomitant depletion of malondialdehyde and nitric oxide levels. They inhibited acetylcholinesterase and butyrylcholinesterase activities, while concomitantly elevated ATPase activity. Treatment with vanillin led to restoration of oxidative-depleted metabolites and reactivation of the pentose phosphate and purine metabolism pathways, with concomitant activation of pathways for histidine and selenoamino metabolisms. While vanillic acid restored and reactivated oxidative-depleted metabolites and pathways but did not activate any additional pathway. Both phenolics portrayed good binding affinity for catalase, with vanillic acid having the higher binding energy of -7.0 kcal/mol. Both phenolics were not cytotoxic on HT22 cells, and their toxicity class were predicted to be 4. Only vanillin was predicted to be permeable across the blood brain barrier (BBB). These results insinuate that vanillin and vanillic acid confer a neuroprotective effect on oxidative brain damage, when vanillin being the most potent.

Anti-inflammatory effects of Beopje curly dock (Rumex crispus L.) in LPS-induced RAW 264.7 cells and its active compounds

Inflammation is a defense response of the body to stimuli. Curly dock (CD) is an herbal food with anti-inflammatory effects. Beopje is an herbal food processing method that reduces toxicity and enhances beneficial effects. This study investigated the effects of CD and Beopje curly dock (CD-B) extracts on lipopolysaccharide (LPS)-induced inflammatory damage in RAW 264.7 cells. Cell survival rate and nitrite concentration were determined using the MTT assay and Griess method, respectively. Enzyme-linked immunosorbent assay was used to detect the inflammatory cytokine levels. The mRNA and protein expression levels of inflammatory associated genes were detected by qPCR and Western blot, respectively. CD and CD-B extracts compositions were assessed by UPLC-Q-TOF MS analysis. Our results indicate that CD-B has a more significant inhibitory effect on the LPS-induced inflammatory response in RAW 264.7 cells than CD, suggesting that the Beopje process potentially enhances the anti-inflammatory effect of CD. PRACTICAL APPLICATIONS: Long-term inflammation can cause a variety of chronic diseases. Therefore, it is necessary to suppress the occurrence of body inflammation in time. This study preliminarily clarified the mechanism of herbal foods to alleviate inflammation by regulating the immune response, and further confirms that applying the Beopje process enhances the anti-inflammatory effect. This research can serve as a significant reference for future research, prevention and treatment of inflammation-related diseases, and the development of functional foods with anti-inflammatory activity. It also provides a theoretical basis for the further reasonable application of Beopje processing method.

Polyphenols with Anti-Amyloid β Aggregation Show Potential Risk of Toxicity Via Pro-Oxidant Properties

Alzheimer's disease (AD) is the most common form of dementia among older people. Amyloid β (Aβ) aggregation has been the focus for a therapeutic target for the treatment of AD. Naturally occurring polyphenols have an inhibitory effect on Aβ aggregation and have attracted a lot of attention for the development of treatment strategies which could mitigate the symptoms of AD. However, considerable evidence has shown that the pro-oxidant mechanisms of polyphenols could have a deleterious effect. Our group has established an assay system to evaluate the pro-oxidant characteristics of chemical compounds, based on their reactivity with DNA. In this review, we have summarized the anti-Aβ aggregation and pro-oxidant properties of polyphenols. These findings could contribute to understanding the mechanism underlying the potential risk of polyphenols. We would like to emphasize the importance of assessing the pro-oxidant properties of polyphenols from a safety point of view.

Regardless of the Brewing Conditions, Various Types of Tea are a Source of Acetylcholinesterase Inhibitors

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized, among others, by abnormally low levels of the neurotransmitter acetylcholine in the brain. Acetylcholinesterase (AChE) plays a significant role in the process through hydrolysis of the acetylcholine neurotransmitter. Currently, the main method for treatment of AD at a symptomatic stage entails administration of AChE inhibitors to patients diagnosed with the disease. However, it is also possible to take certain steps to treat AD by delivering inhibitors with food. There is a growing body of evidence to suggest that tea (Camellia sinensis) shows numerous beneficial properties, including improving cognitive abilities. This is particularly important in the case of AD patients. The study assessed the impact of brewing conditions on the inhibition of AChE activity observed in tea extracts (black, white, or fruit). Our study revealed that neither temperature nor time of brewing influenced the respective infusions’ ability to inhibit the activity of AChE. Anticholinesterase activity was observed in most of the different types of tea that were analyzed, with the highest rate of inhibition (30.46%–48.54%) evidenced in the Biofix Tea Wild Strawberry brand. The results of our research show that tea may be used as a rich source of cholinesterase inhibitors which play a significant role in AD treatment.

The use of catechins in Chinese hamster ovary cell media for the improvement of monoclonal antibody yields and a reduction of acidic species

Catechin compounds have potential benefits for recombinant monoclonal antibody (Mab) production as chemical additives in cell culture media. In this study, four catechin compounds catechin (Cat), epicatechin (EC), gallocatechin-gallate (GCG), and epigallocatechin-gallate (EGCG) were added to cell culture media (at 50 μM) and their effects on the recombinant Chinese hamster ovary (CHO) cell culture, specific productivity, and Mab quality were assessed. The results indicate that the improvement of specific productivity was linked to cell growth inhibition. All catechins caused cell phase growth arrest by lowering the number of cells in the G1/G0 phase and increasing the cells in the S and G2/M phases. Late addition of the catechin resulted in a significantly higher final IgG concentration. Cat and EC caused an improvement in the final antibody titer of 1.5 ± 0.1 and 1.3 ± 0.1 fold, respectively. Catechins with a galloyl group (GCG and EGCG) arrested cell growth and reduced cell specific productivity at the concentrations tested. The Cat-treated IgG was found to have reduced acidic species with a corresponding increase in the main peak.

Flavonoid-Derived Human Phenyl-γ-Valerolactone Metabolites Selectively Detoxify Amyloid-β Oligomers and Prevent Memory Impairment in a Mouse Model of Alzheimer's Disease

SCOPE

Amyloid-β oligomers (AβO) are causally related to Alzheimer's disease (AD). Dietary natural compounds, especially flavonoids and flavan-3-ols, hold great promise as potential AD-preventive agents but their host and gut microbiota metabolism complicates identification of the most relevant bioactive species. This study aims to investigate the ability of a comprehensive set of phenyl-γ-valerolactones (PVL), the main circulating metabolites of flavan-3-ols and related dietary compounds in humans, to prevent AβO-mediated toxicity.

METHODS AND RESULTS

The anti-AβO activity of PVLs is examined in different cell model systems using a highly toxic β-oligomer-forming polypeptide (β23) as target toxicant. Multiple PVLs, and particularly the monohydroxylated 5-(4'-hydroxyphenyl)-γ-valerolactone metabolite [(4'-OH)-PVL], relieve β-oligomer-induced cytotoxicity in yeast and mammalian cells. As revealed by atomic force microscopy (AFM) and other in vitro assays, (4'-OH)-PVL interferes with AβO (but not fibril) assembly and actively remodels preformed AβOs into nontoxic amorphous aggregates. In keeping with the latter mode of action, treatment of AβOs with (4'-OH)-PVL prior to brain injection strongly reduces memory deterioration as well as neuroinflammation in a mouse model of AβO-induced memory impairment.

CONCLUSION

PVLs, which have been validated as biomarkers of the dietary intake of flavan-3-ols, lend themselves as novel AβO-selective, candidate AD-preventing compounds.

Neuroprotective Effects of Lacosamide in Experimental Peripheral Nerve Injury in Rats : A Prospective Randomized and Placebo-Controlled Trial

OBJECTIVE

To evaluate the neuroprotective effects of lacosamide after experimental peripheral nerve injury in rats.

METHODS

A total of 28 male wistar albino rats weighing 300-350 g were divided into four groups. In group I, the sciatic nerve exposed and the surgical wound was closed without injury; in group II, peripheral nerve injuries (PNI) was performed after dissection of the nerve; in group III, PNI was performed after dissection and lacosamide was administered, and in group IV, PNI was performed after dissection and physiological saline solution was administered. At 7 days after the injury all animals were sacrificed after walking track analysis. A 5 mL blood sample was drawn for biochemical analysis, and sciatic nerve tissues were removed for histopathological examination.

RESULTS

There is low tissue damage in lacosamide treated group and antioxidant anzymes and malondialdehyde levels were higher than non-treated and placebo treated group. However there was no improvement on clinical assessment.

CONCLUSION

The biochemical and histological analyses revealed that lacosamide has neuroprotective effect in PNI in rats. This neuroprotective capacity depends on its scavenger role for free oxygen radicals by increasing antioxidant enzyme activity.

Development of a New Cell-Based Oral Model To Study the Interaction of Oral Constituents with Food Polyphenols

Some polyphenols have unpleasant taste properties such as astringency, which could interfere with consumers' choices. The knowledge on astringency mechanisms points that astringency is a complex phenomenon probably related to more than one physical-chemical mechanism. Thus, this work aims to develop a new and more realistic cell-based model containing human saliva, mucosa pellicle, and an oral cell line (HSC-3) to understand the oral molecular events that could contribute to the overall astringency perception. This model was then used to study the interactions with a food procyanidin fraction (PF) by HPLC. In general, the results revealed higher interaction (synergism) for the model with all the referred oral constituents (mucosa pellicle, salivary proteins, and HSC-3 cell line, HSCMuSp) when compared to the interaction with individual constituents, the PF + cells or PF + saliva. Regarding the procyanidins, a significant interaction was observed for the procyanidin monomer EcG, procyanidin dimers B7 and B2G, and trimer C1.

Multiple pharmacological and toxicological investigations on Tanacetum parthenium and Salix alba extracts: Focus on potential application as anti-migraine agents

Migraine is one of the most common neurological disorder, which has long been related to brain serotonin (5-HT) depletion and neuro-inflammation. Despite many treatment options are available, the frequent occurrence of unacceptable adverse effects further supports the research toward nutraceuticals and herbal preparations, among which Tanacetum parthenium and Salix alba showed promising anti-inflammatory and neuro-modulatory activities. The impact of extract treatment on astrocyte viability, spontaneous migration and apoptosis was evaluated. Anti-inflammatory/anti-oxidant effects were investigated on isolated rat cortexes exposed to a neurotoxic stimulus. The lactate dehydrogenase (LDH) release, nitrite levels and 5-HT turnover were evaluated, as well. A proteomic analysis was focused on specific neuronal proteins and a fingerprint analysis was carried out on selected phenolic compounds. Both extracts appeared able to exert in vitro anti-oxidant and anti-apoptotic effects. S. alba and T. parthenium extracts reduced LDH release, nitrite levels and 5-HT turnover induced by neurotoxic stimulus. The downregulation of selected proteins suggest a neurotoxicity, which could be ascribed to an elevated content of gallic acid in both S. alba and T. parthenium extracts. Concluding, both extracts exert neuroprotective effects, although the downregulation of key proteins involved in neuron physiology suggest caution in their use as food supplements.

Anthocyanins and Their Metabolites as Therapeutic Agents for Neurodegenerative Disease

Neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (ALS), are characterized by the death of neurons within specific regions of the brain or spinal cord. While the etiology of many neurodegenerative diseases remains elusive, several factors are thought to contribute to the neurodegenerative process, such as oxidative and nitrosative stress, excitotoxicity, endoplasmic reticulum stress, protein aggregation, and neuroinflammation. These processes culminate in the death of vulnerable neuronal populations, which manifests symptomatically as cognitive and/or motor impairments. Until recently, most treatments for these disorders have targeted single aspects of disease pathology; however, this strategy has proved largely ineffective, and focus has now turned towards therapeutics which target multiple aspects underlying neurodegeneration. Anthocyanins are unique flavonoid compounds that have been shown to modulate several of the factors contributing to neuronal death, and interest in their use as therapeutics for neurodegeneration has grown in recent years. Additionally, due to observations that the bioavailability of anthocyanins is low relative to that of their metabolites, it has been proposed that anthocyanin metabolites may play a significant part in mediating the beneficial effects of an anthocyanin-rich diet. Thus, in this review, we will explore the evidence evaluating the neuroprotective and therapeutic potential of anthocyanins and their common metabolites for treating neurodegenerative diseases.

Protective effect of gallic acid against arsenic-induced anxiety-/depression- like behaviors and memory impairment in male rats

The purpose of the present study is to determine the effects of gallic acid (GA) on sodium arsenite (iAS)-induced behavior deficits and memory alteration in male rats. Thirty six animals were divided in to 6 groups (six animals in each) (i) saline+saline; (ii) saline+GA (50 mg/kg); (iii) saline+ GA (100 mg/kg) (iv) iAS + saline; (v) iAS + GA(50 mg/kg); (vi) iAS + GA (100 mg/kg). Animals were treated with iAS (2.5 mg/kg/ml); GA (50 and 100 mg/kg/ml) and saline (0.9%; 1 ml/kg) for 4 weeks. Repeated administration of iAS increases immobility time in forced swim test and decreases time spent in open arm (elevated plus maze) and light box (light dark activity box test) suggests depression like and anxiety-like symptoms respectively. On the other hand, animals treated with iAS + GA decreases immobility time and increases time spent in open arm and light box than saline+iAS treated animals suggests anxiolytic and antidepressant-like behavior of GA. Repeated administration of iAS also involves in memory impairment as observed in the Morris water maze test that is reversed by co-administration of GA, indicates that GA also involves in the enhancement of memory. Brain malondialdehyde (MDA) levels, antioxidant enzymes and acetylcholinesterase (AChE) activities also observed in the present study. Results show that iAS produces oxidative stress by increasing lipid peroxidation and decreasing antioxidant enzyme activity. Conversely co-administration of GA produces antioxidant effects by normalization of oxidative stress induced by iAS. Alteration in iAS induced AChE activity is also reversed by GA. It is suggested that GA via its antioxidant potential, has protective effects on iAS induced behavioral deficits and memory alteration. The findings have a strong implication on iAS induced neurological diseases, such as depression, anxiety, Alzheimer's disease and dementia etc.

Biopharmaceutical Monotargeting versus 'Universal Targeting' of Late-Onset Alzheimer's Disease Using Mixtures of Pleiotropic Natural Compounds

A five-year close reading of the scientific literature on late-onset Alzheimer’s disease (AD) has prompted the invention of a novel therapeutic method that biomechanistically targets the targetable disease-process targets of AD with one or another mixture of non-toxic pleiotropic natural compounds. The featured mixture herein is comprised of curcumin, resveratrol, and EGCG. The mixture’s targets include central pathological elements of AD (including amyloid, tau, synaptic dysfunction, oxidative stress, mitochondrial dysfunction, and aberrant neuroinflammation), modifiable risk factors, comorbidities, and epigenetic elements. The featured mixture and other such mixtures are suitable for long-term use, and may be applied to any stage of AD, including primary and secondary prevention. Such mixtures also would be amenable for use as pre-treatment, co-treatment, and post-treatment applications with certain biopharmaceutical agents. The targeting focus here is the major credible hypotheses of AD. The focus of future such articles will include other AD-related targets, modifiable risk factors and comorbidities, APOE4, epigenetic factors, bioavailability, dose response, and implications for clinical testing. The “universal targeting” method described herein—that is, “targeting the targetable targets” of AD using certain mixtures of natural compounds—is reprogrammable and thus is applicable to other chronic neurological conditions, including Parkinson’s disease, vascular dementia, ischemic-stroke prevention and recovery, and sports-related head injuries and sequelae leading to chronic traumatic encephalopathy.

Neuroprotective and Anti-Amyloid β Effect and Main Chemical Profiles of White Tea: Comparison Against Green, Oolong and Black Tea

White tea (WT) is one of six tea types originally derived from Fujian Province, China. White tea is known for its health-promoting properties. However, the neuroprotective and anti-aggregatory properties of WT against the hallmark toxic Alzheimer's protein, Aβ have not been investigated. In this study, WT, green tea (GT), oolong tea (OT) and black tea (BT) were manufactured using tea leaves from the cultivar Camellia sinensis (Jin Guanyin). The protective effects of these tea extracts were then studied under oxidative stress conditions via t-bhp and H₂O₂ exposure, in addition to Aβ treatment using a PC-12 cell model. Each tea type failed to rescue PC-12 cells from either t-bhp or H₂O₂-mediated toxicity, however each extract exerted significant protection against Aβ-evoked neurotoxicity. Results of the Thioflavin T Kinetic (ThT) and TEM assay showed that Aβ aggregate formation was inhibited by each tea type. Additionally, TEM also supported the different anti-aggregatory effect of WT by modifying Aβ into an amorphous and punctate aggregate morphology. Higher accumulated precedent or potential neuroprotective compounds in WT, including ECG''3Me, 8-C-ascorbyl-EGCG, GABA and Gln, in addition to flavonol or flavone glycosides detected by using UPLC-QTOF-MS and UPLC-QqQ-MS, may contribute to a favourable anti-aggregative and neuroprotective effect of WT against Aβ.