Effect of botanical extracts containing carnosic acid or rosmarinic acid on learning and memory in SAMP8 mice

Dietary supplementation and the role of phytochemicals against the Alzheimer's disease: Focus on polyphenolic compounds

Alzheimer's disease is a complicated, multifaceted, neurodegenerative illness that places an increasing strain on healthcare systems. Due to increasing malfunction and death of nerve cells, the person suffering from Alzheimer's disease (AD) slowly and steadily loses their memories, cognitive functions and even their personality. Although medications may temporarily enhance memory, there are currently no permanent therapies that can halt or cure this irreversible neurodegenerative process. Nonetheless, fast progress in comprehending the cellular and molecular abnormalities responsible for neuronal degeneration has increased confidence in the development of viable prevention and treatments. All FDA-approved anti-AD medications have merely symptomatic effects and cannot cure the illness. This necessitates the pursuit of alternate treatments. Accumulating data shows that systemic neuroinflammation, oxidative stress and associated mitochondrial dysfunction play crucial roles in the etiology of AD and precede its clinical presentation. Therefore, innovative therapeutic approaches targeting these pathophysiological components of Alzheimer's disease are being explored aggressively in the present scenario. Phytochemicals such as resveratrol, curcumin, quercetin, genistein and catechins are prospective therapies owing to their capacity to alter key AD pathogenetic pathways, such as oxidative stress, neuroinflammation, and mitochondrial dysfunction. The use of new phytochemical delivery strategies would certainly provide the possibility to solve several issues with standard anti-AD medicines. In this review, the roles of phytophenolic compound-based treatment strategies for AD are discussed.

In silico anti-alzheimer study of phytochemicals from Lamiaceae family through GSK3-β inhibition

Glycogen synthase kinase 3-beta (GSK3-β) is a serine-threonine protease expressed in the brain, and its hyperactivity is considered the underlying cause of Alzheimer's disease. This enzyme requires an ATP molecule in its N-terminal lobe to phosphorylate its substrates, with the most important substrate being the Tau protein. This study focuses on the inhibitory mechanism of four naturally occurring compounds-apigenin, luteolin, rosmarinic acid, and salvianolic acid-from the Laminaceae family against GSK3-β. The orientation of the ligands within the ATP-binding pocket of GSK3-β and their binding energy were determined through molecular docking. Additionally, molecular dynamics simulations was conducted to study the conformational changes induced by the ligands in the protein structure. The results showed that apigenin and salvianolic acid achieved deeper parts of the cavity compared to luteolin and rosmarinic acid and formed stable complexes with the enzyme. In the rosmarinic acid complex, the enzyme exhibited the most exposed conformation. On the other hand, luteolin binding caused a small closure of the opening, suggesting a potentially ATP-competitive role. Our results suggest these compounds as lead candidates for the design of GSK3-β inhibitors.

Deciphering Neuroprotective Effect of Rosmarinus officinalis L. (syn. Salvia rosmarinus Spenn.) through Preclinical and Clinical Studies

Rosmarinus officinalis L. (RO, rosemary) is a well-known medicinal, aromatic, and culinary herb with traditional use in European folk medicine against memory deficits and neurodegenerative disorders. This review highlights the different neuroprotective activities of RO investigated in both preclinical and clinical studies, as well as in silico molecular docking of bioactive compounds found in RO. The neuroprotective effect of RO was searched through databases including PubMed, Web of Science (WoS), Scopus, and Clinical Trials using the keywords "Rosmarinus officinalis, rosemary, neuroprotective effect, memory, cognitive dysfunction, Alzheimer's disease." RO, which is rich in secondary metabolites that have memory-enhancing potential, has displayed neuroprotection through different molecular mechanisms such as inhibition of cholinesterase, modulation of dopaminergic and oxytocinergic systems, mediation of oxidative and inflammatory proteins, involved in neuropathic pain, among others. RO extracts exhibited antidepressant and anxiolytic activities. Also, the plant has shown efficacy in scopolamine-, lipopolysaccharide-, AlCl3-, and H2O2-induced amnesia as well as amyloid-beta- and ibotenic acid-induced neurotoxicity and chronic constriction injury-related oxidative stress memory and cognitive impairments in animal models. A few clinical studies available supported the neuroprotective effects of RO and its constituents. However, more clinical studies are needed to confirm results from preclinical studies further and should include not only placebo-controlled studies but also studies including positive controls using approved drugs. Many studies underlined that constituents of RO may have the potential for developing drug candidates against Alzheimer's disease that possess high bioavailability, low toxicity, and enhanced penetration to CNS, as revealed from the experimental and molecular docking analysis.

Ursolic acid and rosmarinic acid ameliorate alterations in hippocampal neurogenesis and social memory induced by amyloid beta in mouse model of Alzheimer's disease

Alzheimer's disease (AD) is a multifaceted neurodegenerative disorder characterized by substantial neuronal damage which manifests in the form of deficits in memory and cognition. In spite of the debilitating nature of Alzheimer's disease (AD), a dearth of treatment strategies calls for the need to develop therapeutic agents that stimulate neurogenesis and alleviate the associated cognitive deficits. The present study investigates the therapeutic potential of two major phytochemicals, rosmarinic acid (RA) and ursolic acid (UA) in an amyloid beta_1-42 (Aβ_1-42)-induced model of AD. UA, a natural pentacyclic triterpenoid and RA, a phenolic ester are major bioactive constituents of Rosmarinus officinalis, which is a medicinal herb belonging to family Lamiaceae and exhibiting significant biological properties including neuroprotection. Donepezil, a second generation cholinesterase inhibitor approved for the treatment of mild, moderate and severe Alzheimer's disease (AD) is used as control. Out of eight groups of male BALB/c mice, stereotaxic surgery was performed on four groups (n = 6 each) to introduce Aβ_1-42 in the hippocampus followed by treatment with vehicle (phosphate-buffered saline (PBS)), donepezil, UA or RA. The other four groups were given vehicle, donepezil, UA and RA only. Behavior analysis for social interaction was performed which constitutes the social affiliation and the social novelty preference test. Presence of Aβ plaques and expression of neurogenesis markers i.e., doublecortin (DCX) and Ki-67 were also assessed. Results revealed the neuroprotective effect of UA and RA observed through substantial reduction in Aβ plaques as compared to the Aβ_1-42- and donepezil-treated groups. The neuronal density was also restored as evident via DCX and Ki-67 immunoreactivity in Aβ_1-42 + RA and Aβ_1-42+UA-treated groups in comparison to Aβ_1-42-treated and Aβ_1-42+donepezil-treated groups. The social affiliation was reestablished in the Aβ_1-42 administered groups treated with UA and RA. Molecular docking studies further validated the comparable binding of UA and RA with Ki-67 and DCX to that of donepezil. Our findings suggest that UA and RA are potential neuroprotective compounds that reverses the histological hallmarks of AD and ameliorate impaired social memory and hippocampal neurogenesis.

In-vivo evaluation of immunomodulatory activity of crude extract and solvent fractions of Cyphostemma adenocaule (Steud. ex A.Rich)

Background

Various indigenous medicinal systems including Ethiopians used Cyphostemma adenocaule for managing tumors, helminthiasis, snake envenomation, rabis virus, splenomegaly, and other immunological disorders. However, no scientific study was conducted to validate these traditional medicinal claims of the plant. Therefore, this study aimed to evaluate the in-vivo immunomodulatory activity of the crude root extract and its solvent fractions.

Methods

Carbon clearance rate and humoral antibody titer were determined for 100, 200, and 400 mg/kg of crude extract and solvent fractions among Swiss albino mice. Carbon ink and sheep red blood cells were used as antigens for carbon clearance assay and humoral antibody titer respectively.

Results

Among all groups, an increase in both carbon clearance rate and the humoral antibody titer was observed with an increase in the dose of both crude extract and solvent fractions. Compared to the solvent fractions of comparable doses, the crude extract showed better activity. The crude extract at a dose of 400 mg/kg revealed the highest and statistically significant augmentation of carbon clearance rate (0.1100 ± 0.0124) and humoral antibody titer (96.00 ± 14.31) compared to the vehicle control group.

Conclusion

From our study, it is concluded that crude extract and n-butanol fraction showed promising immunostimulant activity by enhancing carbon clearance rate and humoral antibody titer.

Neuroprotective potential of terpenoid-rich extracts from orange juice by-products obtained by pressurized liquid extraction

•

Orange juice by-products valorized by green PLE process.

•

Terpenoid-rich PLE extract with enhanced in-vitro neuroprotective activity.

•

Molecular docking between terpenoids and active sites of the target enzymes.

•

Selected PLE extracts show human cell-based neuroprotection capacity.

Pressurized liquid extraction (PLE) conditions were optimized to improve the recovery of orange (Citrus sinensis) by-products terpenoids. The neuroprotective potential of the PLE extracts were tested against a set of in-vitro assay (antioxidant (ABTS), reactive oxygen/nitrogen species (ROS/RNS)) as well as enzymatic tests (acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and lipoxygenase (LOX)). Gas chromatography coupled to high-resolution mass spectrometry (GC-q-TOF-MS) analysis revealed a higher enrichment in mono- and sesquiterpenoids of the PLE extracts with the highest neuroprotection capacity. In-silico molecular docking analysis showed the specific interaction of representative terpenoids with enzymes active sites. The results demonstrate that the selected extract at 100 °C and 30 minutes possesses high antioxidant (ABTSIC50 = 13.5 μg mL⁻¹; ROSIC50 = 4.4 μg mL⁻¹), anti-cholinesterase (AChEIC50 = 137.1 vg  L⁻¹; BChEIC50 = 147.0 μg mL⁻¹) and anti-inflammatory properties (against IL-6 and LOXIC50 = 76.1 μg mL⁻¹), with low cytotoxicity and protection against L-glutamic acid in cell models.

Mediterranean natural extracts improved cognitive behavior in zebrafish and healthy rats and ameliorated lps-induced cognitive impairment in a sex dependent manner

BACKGROUND

Several findings suggest neuroinflammation as a contributing factor for the onset of psychiatric disorders such as Alzheimer's disease, depression, and anxiety. There is increasing evidence pointing out that the Mediterranean diet influences brain and behavior. Mediterranean herbs and spices have been shown to be within those components of the Mediterranean diet involved in cognitive enhancement. Thus, we investigated the influence of Mediterranean natural extracts (MNE), Rosemary extract (RE) and Glycyrrhiza glabra root extract (GGRE), on cognitive behavior.

RESULTS

Adult zebrafish were exposed to RE or GGRE (100 and 250 mg/L) treatments. Both MNE improved memory retention during the T-maze test, although no improvements were observed during the novel object preference. Similarly, chronic administration of RE (150 mg/Kg) and GGRE (150 mg/Kg) improved, respectively, spatial and retention memory, as assessed by the Morris Water Maze (MWM), and the Elevated Plus Maze (EPM) in healthy male rats. However, no improvements were observed during the novel object recognition. Finally, male, and female rats were chronically treated with lipopolysaccharide [(LPS) 300 ug/kg] and orally administered with RE. Interestingly, RE reversed LPS-induced cognitive deficit during the MWM and EPM in female rats.

CONCLUSIONS

We found that MNE improved cognition in both zebrafish and rats. Moreover, MNE rescued LPS-induced cognitive impairment in a gender-specific manner. Therefore, our study supports the view that zebrafish represent a valuable preclinical model for drug discovery in neuroscience. These findings contribute to an exciting and growing body of research suggesting that MNE may play an important role in the prevention of cognitive impairment.

Novel Perceptions on Chemical Profile and Biopharmaceutical Properties of Mentha spicata Extracts: Adding Missing Pieces to the Scientific Puzzle

Mentha spicata is one of the most popular species in the genus, and it is of great interest as a gastrointestinal and sedative agent in the folk medicine system. In this study, different M. spicata extracts, obtained by the use of four solvents (hexane, chloroform, acetone and acetone/water) were chemically characterized using HPLC-ESI-MS n, which allowed for identification of 27 phenolic compounds. The extracts' antioxidant and enzyme inhibitory properties were investigated. In addition, neuroprotective effects were evaluated in hypothalamic HypoE22 cells, and the ability of the extracts to prevent the hydrogen peroxide-induced degradation of dopamine and serotonin was observed. The best antioxidant effect was achieved for all the extraction methods using acetone/water as a solvent. These extracts were the richest in acacetin, eriodictyol, hesperidin, sagerinic acid, naringenin, luteolin, chlorogenic acid, chrysoeriol and apigenin. The intrinsic antioxidant and enzyme inhibition properties of the acetone/water extract could also explain, albeit partially, its efficacy in preventing prostaglandin E2 overproduction and dopamine depletion (82.9% turnover reduction) in HypoE22 cells exposed to hydrogen peroxide. Thus, our observations can provide a scientific confirmation of the neuromodulatory and neuroprotective effects of M. spicata.

Cognition enhancing effect of rosemary (Rosmarinus officinalis L.) in lab animal studies: a systematic review and meta-analysis

Patients with mild cognitive impairment eventually progress to Alzheimer's disease (AD) causing a strong impact on public health. Rosmarinus officinalis has long been known as the herb of remembrance and can be a potential cognition enhancer for AD. The aim of this review was to summarize the qualitative and quantitative aspects of R. officinalis and its active constituents in enhancing cognition. A structured search was conducted on Google Scholar and PubMed to find relevant studies that assessed the effect of R. officinalis extract or any of its active constituents on cognitive performance in animals. The following information was extracted from each study: 1) article information; 2) characteristics of study animals; 3) type of intervention: type, dose, duration, and frequency of administration of R. officinalis; and 4) type of outcome measure. Data were analyzed using Review Manager and meta-analysis was performed by computing the standardized mean difference. Twenty-three studies were selected for qualitative analysis and fifteen for meta-analysis. From the fifteen included papers, 22 with 35 comparisons were meta-analyzed. Effect sizes for intact and cognitively impaired animals were 1.19 (0.74, 1.64) and 0.57 (0.19, 0.96), indicating a positive effect on both groups. The subgroup analyses showed substantial unexplained heterogeneity among studies. Overall, R. officinalis improved cognitive outcomes in normal and impaired animals, and results were robust across species, type of extract, treatment duration, and type of memory. However, studies had a considerable amount of heterogeneity, and subgroup analyses failed to find any heterogeneity moderator.

Antidepressant- and anxiolytic-like activities of Rosmarinus officinalis extract in rodent models: Involvement of oxytocinergic system

BACKGROUND

Oxytocin (OXT), a neuropeptide involved in mammal reproductive and prosocial behaviors, has been reported to interact with various stressor-provoked neurobiological changes, including neuroendocrine, neurotransmitter, and inflammatory processes. In view of disturbances in psychosocial relationships due to social isolation and physical distancing measures amid the COVID-19 pandemic, being one of the triggering factors for the recent rise in depression and anxiety, OXT is a potential candidate for a new antidepressant.

METHODS

In this present study, we have aimed to investigate the effects of oral administration of Rosmarinus officinalis extract (RE), extracted from distillation residue of rosemary essential oil, on central OXT level in the context of other stress biomarkers and neurotransmitter levels in mice models. Tail suspension test (TST) and elevated plus maze test (EPMT) following LPS injection were employed to assess depressive- and anxiety-like behavior in mice, respectively.

FINDINGS

Pretreatment with RE for seven days significantly improved behavior in TST and EPMT. Whole-genome microarray analysis reveals that RE significantly reversed TST stress-induced alterations in gene expressions related to oxytocinergic and neurotransmitter pathways and inflammatory processes. In both models, RE significantly increased central Oxt and Oxtr expressions, as well as OXT protein levels. RE also significantly attenuated stress-induced changes in serum corticosterone, brain and serum BDNF levels, and brain neurotransmitters levels in both models.

INTERPRETATION

Altogether, our study is the first to report antidepressant- and anxiolytic-like activities of RE through modulating oxytocinergic system in mice brain and thus highlights the prospects of RE in the treatment of depressive disorders of psychosocial nature.

The traditional uses, phytochemistry and pharmacology of spearmint (Mentha spicata L.): A review

ETHNOPHARMACOLOGY RELEVANCE

Mentha spicata L. (Lamiaceae), commonly called Spearmint, is wildly cultivated worldwide for its remarkable aroma and commercial value. In addition to traditional foods flavouring agent, M. spicata is well known for its traditional medicinal uses, particularly for the treatment of cold, cough, asthma, fever, obesity, jaundice and digestive problems.

AIM OF THE REVIEW

This review aims to critically appraise scientific literature regarding the traditional uses, bioactive chemical constituents and pharmacological activities of M. spicata.

MATERIALS AND METHODS

A review of the literature information on M. spicata was searched from scientific electronic search databases (Google Scholar, PubMed, Web of Science, ACS, Science Direct, Taylor and Francis, Wiley, Springer and SCOPUS. Structures for secondary metabolites were confirmed using PubChem and ChemSpider.

RESULTS

The studies conducted on either crude extracts, essential oil or isolated pure compounds from M. spicata had reported a varied range of biological effects including antibacterial, antifungal, antioxidant, hepatoprotective, antidiabetic, cytotoxic, anti-inflammatory, larvicidal activity, antigenotoxic potential and antiandrogenic activities. Phytochemical analysis of various parts of M. spicata revealed 35 chemical constituents, belonging to phenolic acids, flavonoids and lignans.

CONCLUSION

The review finding indicates that the pharmacological properties of M. spicata supported its traditional uses. The essential oils and extracts showed remarkable antimicrobial, antioxidant, anticancer, anti-inflammatory and hepatoprotective activities. However, more studies, especially in vivo experiments and clinical trials of the human to evaluate cellular and molecular mechanisms based pharmacological, bioactive effectiveness and safety investigation, should be undertaken in the future to provide stronger scientific proof for their traditional medicinal properties.

A Randomized, Double-Blind, Placebo-Controlled Trial of a Polyphenol Botanical Blend on Sleep and Daytime Functioning

Despite the high prevalence of subclinical sleep disturbances, existing treatments are either potent prescription medications or over-the-counter supplements with minimal scientific support and numerous side effects. However, preliminary evidence shows that polyphenols such as rosmarinic acid and epigallocatechin gallate can support healthy sleep without significant side effects. Therefore, the present study examined whether a polyphenol botanical blend (PBB) could improve sleep and/or daytime functioning in individuals with subclinical sleep disturbances. A total of 89 individuals completed a double-blind, randomized trial of daily treatment with PBB (n = 43) or placebo (n = 46) 30 min before bed for 30 days. Participants were monitored for changes in sleep (by sleep diary and an activity tracker), mood, and neurocognitive functioning. After 30 days, PBB improved diary sleep quality (p = 0.008) and reduced insomnia severity (p = 0.044) when compared to placebo. No other changes in sleep outcomes were observed. Additionally, PBB did not impair neurocognitive functioning, and some improvement was noted in vigilant attention, working memory, and risk assessment. Among individuals with subclinical sleep disturbances, PBB improved sleep quality, insomnia severity, and neurocognitive functioning over placebo. These findings indicate that polyphenol compounds may be useful for improving certain aspects of sleep without compromising neurocognitive functioning.

Rosmarinic acid and ursolic acid alleviate deficits in cognition, synaptic regulation and adult hippocampal neurogenesis in an Aβ1-42-induced mouse model of Alzheimer's disease

BACKGROUND

Rosmarinus officinalis, commonly known as rosemary, is a medicinal herb that presents significant biological properties such as antimicrobial, antioxidant, anti-inflammatory, anti-diabetic and anti-depressant activities. Recent findings correlate impaired adult neurogenesis, which is crucial for the maintenance of synaptic plasticity and hippocampal functioning, synaptic regulation with the pathological hallmarks of Alzheimer's disease (AD). These observations call for the need to developing compounds that promote neurogenesis and alleviates deficits in cognition and synaptic regulation.

PURPOSE AND STUDY DESIGN

The present study was conducted to determine the proneurogenic effects of R. officinalis and its active compounds (ursolic acid and rosmarinic acid) in comparison to Donepezil in an Aβ1-42-induced mouse model of AD.

METHODS

BALB/c mice were divided into ten groups. Half were injected with Aβ1-42 in the hippocampus through stereotaxic surgery to generate the disease groups. The other half received control injections. Each set of five groups were administered orally with vehicle, an ethanolic extract of R. officinalis, ursolic acid, rosmarinic acid or donepezil. Behavior analysis included the Morris water maze test, the novel object recognition test and the Elevated plus maze. The mice were then sacrificed and the hippocampal tissue was processed for immunohistochemistry and gene expression analysis.

RESULTS

The results show a protective effect by rosmarinic acid and ursolic acid in reversing the deficits in spatial and recognition memory as well as changes in anxiety induced by Aβ1-42. The neuronal density and the expression levels of neurogenic (Ki67, NeuN and DCX) and synaptic (Syn I, II, III, Synaptophysin and PSD-95) markers were also normalized upon treatment with rosmarinic and ursolic acid.

CONCLUSION

Our findings indicate the potential of R. officinalis and its active compounds as therapeutic agents against Aβ1-42-induced neurotoxicity in AD.

Amelioration of oxidative stress and neuroinflammation in lipopolysaccharide-induced memory impairment using Rosmarinic acid in mice

Oxidative stress plays a pivotal part in the manifestation of neuroinflammation, which further leads to neurodegenerative diseases like Alzheimer's disease (AD). Systemic administration of lipopolysaccharide (LPS) induces neuroinflammation resulting in memory impairment (MI) and cognitive decline. In this study, we evaluated whether prophylactic administration of Rosmarinic acid (RA), a naturally occurring compound, exerts a neuroprotective effect in LPS-induced MI and cognitive decline. Herein, Swiss albino mice were pre-treated with RA (0.5 mg/kg and 1 mg/kg i.p.) for 28 days and were intermittently exposed to LPS (0.25 mg/kg i.p.) for 7 days. LPS caused poor memory retention and increased cognitive decline in Morris water maze (MWM) and Y maze paradigms respectively. Additionally, LPS increased oxidative stress which was denoted by a decrease in superoxide dismutase (SOD) activity, decrease in reduced glutathione (GSH) levels, and increased lipid peroxidation in the brain. Imbalance in the cholinergic system was analyzed by measuring the acetylcholinesterase (AChE) activity. Pre-treatment with RA improved memory and behavioral disturbances by alleviating oxidative stress and AChE activity. LPS augmented levels of tumor necrosis factor (TNF-α), interleukin (IL)-6, caspase-3, and c-Jun. Pre-treatment with RA revitalized the elevated levels of proinflammatory cytokines and apoptotic proteins. In conclusion, this study showcases the amelioration of MI by RA in LPS-challenged memory and cognitive decline, which could be credited to its anti-oxidant effect, inhibitory effect on both proinflammatory cytokines and apoptotic regulators, and reduction in AChE activity.

Simultaneous Determination of Multiple Reactive Carbonyl Species in High Fat Diet-Induced Metabolic Disordered Mice and the Inhibitory Effects of Rosemary on Carbonyl Stress

As potential endogenous biomarkers, reactive carbonyl species (RCS) have gained abundant attention for monitoring oxidative and carbonyl stress. However, there is no accurate method to evaluate multiple RCS in biological samples. In this study, a 2,4-dinitrophenylhydrazine (DNPH) derivatization-based LC-MS method was developed and validated to quantitate eight RCS: malondialdehyde (MDA), acrolein (ACR), 4-hydroxy-2-nonenal (4-HNE), 4-oxo-2-nonenal (4-ONE), methylglyoxal (MGO), glyoxal (GO), 3-deoxyglucosone (3-DG), and 2-keto-d-glucose (2-Keto). Subsequently, the method was applied to assess the RCS in low fat (LF), high fat (HF), and HF plus rosemary extract (RE) diet-fed mouse samples. The quantitative results on RCS levels indicated that the HF diet significantly increased the total RCS levels in mouse urine, plasma, and kidney with an average rate of 280.69%, 153.87%, and 61.30%, respectively. The RE administration significantly inhibited the elevated RCS levels induced by the HF diet, especially for MDA, 4-ONE, 4-HNE, and 2-Keto in mouse plasma, and ACR and 2-Keto in mouse kidney. This is the first study to simultaneously measure eight RCS in biological samples and demonstrate that RE was able to eliminate the accumulation of the HF diet-induced RCS.

Bioactive constituents from Thunbergia erecta as potential anticholinesterase and anti-ageing agents: Experimental and in silico studies

Acetylcholinesterase (AChE) inhibitor and telomerase reverse transcriptase (TERT) potentiator phytochemicals are highly targeted as anti-Alzheimerꞌs disease and as an anti-ageing process. A phytochemical study of Thunbergia erecta aerial parts resulted in the isolation of ten compounds (1-10). Their structures were identified based on spectral data and comparison with literature values. The activity of our pure isolates on AChE and TERT enzymes by documented in vitro assay methods were evaluated. The results indicated that apigenin (2), vanillic acid (4), and acacetin-7-O-β-D-glucoside (7) exhibited potent inhibition of AChE (IC₅₀ 37.33, 30.80 and 49.57 ng/mL, respectively), compared to the standard drug donepezil (IC₅₀ 31.25 ng/mL). In the TERT enzyme assay, compound 7 triggered a 1.66‑fold increase in telomerase activity at the concentration of 2.85 ng/ml. This is the first study that demonstrates that compound 7 isolated from T. erecta can lead to such telomerase activity relative to control cells. Virtual screening studies including docking, rapid overlay chemical structure (ROCS), and calculated structure-property relationships (SPR) were implemented in this work. Molecular docking studies supported the binding of compounds 2, 4, and 7 through hydrogen bonds (HBs) formation to essential amino acid residues namely ARG:24 A, SER:347 A, LYS:51 A, PHE:346 A, and GLY:345 A of acetylcholinesterase. ROCS and SPR analyses realized compound 2 as a possible treatment of Alzheimer's disease and as a lead compound for drug development process through applying semisynthetic modifications.

Effects of Continuous Intake of Rosemary Extracts on Mental Health in Working Generation Healthy Japanese Men: Post-Hoc Testing of a Randomized Controlled Trial

We previously performed a 4 week interventional trial that suggested that continuous intake of rosemary extract improves the mood states, fatigue, and cognitive function of working generation healthy adult Japanese men. However, the severity of depression in participants in our previous study was relatively mild. Therefore, in the present study, a post-hoc analysis of our previous study was conducted, limited to participants whose total mood disturbance (TMD) scores, which indicate greater mood disturbance, were above the median at baseline, to evaluate whether rosemary extract was effective for individuals with poor mental health. Following the intervention, the scores of TMD and “Confusion-Bewilderment” were significantly decreased (both p < 0.05), and scores of “Vigor-Activity” were significantly increased in the rosemary group (n = 8) compared with those in the control group (n = 13; p < 0.01). When comparing the scores from pre- and post-intervention, significant improvements in “Tension-Anxiety”, “Vigor-Activity”, “Fatigue on awakening”, “Daytime sleepiness”, and “Psychomotor speed” were observed in the rosemary group only (all p < 0.05). Based on these results, it was expected that rosemary extracts were effective for improving the mental energy and sleep quality of work-age men with poor mental health.

Spearmint Extract Containing Rosmarinic Acid Suppresses Amyloid Fibril Formation of Proteins Associated with Dementia

Neurological dementias such as Alzheimer's disease and Lewy body dementia are thought to be caused in part by the formation and deposition of characteristic insoluble fibrils of polypeptides such as amyloid beta (Aβ), Tau, and/or α-synuclein (αSyn). In this context, it is critical to suppress and remove such aggregates in order to prevent and/or delay the progression of dementia in these ailments. In this report, we investigated the effects of spearmint extract (SME) and rosmarinic acid (RA; the major component of SME) on the amyloid fibril formation reactions of αSyn, Aβ, and Tau proteins in vitro. SME or RA was added to soluble samples of each protein and the formation of fibrils was monitored by thioflavin T (ThioT) binding assays and transmission electron microscopy (TEM). We also evaluated whether preformed amyloid fibrils could be dissolved by the addition of RA. Our results reveal for the first time that SME and RA both suppress amyloid fibril formation, and that RA could disassemble preformed fibrils of αSyn, Aβ, and Tau into non-toxic species. Our results suggest that SME and RA may potentially suppress amyloid fibrils implicated in the progression of Alzheimer's disease and Lewy body dementia in vivo, as well.

Carnosic acid improves porcine early embryonic development by inhibiting the accumulation of reactive oxygen species

Carnosic acid (CA), a natural catechol rosin diterpene, is used as an additive in animal feeds and human foods. However, the effects of CA on mammalian reproductive processes, especially early embryonic development, are unclear. In this study, we added CA to parthenogenetically activated porcine embryos in an in vitro culture medium to explore the influence of CA on apoptosis, proliferation, blastocyst formation, reactive oxygen species (ROS) levels, glutathione (GSH) levels, mitochondrial membrane potential, and embryonic development-related gene expression. The results showed that supplementation with 10 μM CA during in vitro culture significantly improved the cleavage rates, blastocyst formation rates, hatching rates, and total numbers of cells of parthenogenetically activated porcine embryos compared with no supplementation. More importantly, supplementation with CA also improved GSH levels and mitochondrial membrane potential, reduced natural ROS levels in blastomeres, upregulated Nanog, Sox2, Gata4, Cox2, Itga5, and Rictor expression, and downregulated Birc5 and Caspase3 expression. These results suggest that CA can improve early porcine embryonic development by regulating oxidative stress. This study elucidates the effects of CA on early embryonic development and their potential mechanisms, and provides new applications for improving the quality of in vitro-developed embryos.

Aromatherapy improves cognitive dysfunction in senescence-accelerated mouse prone 8 by reducing the level of amyloid beta and tau phosphorylation

Alzheimer’s disease (AD) is a progressive neurodegenerative disease and is known to be the most common cause of dementia. We previously described the benefits of aromatherapy on the cognitive function of patients with AD utilizing various aromatic essential oils; however, its mechanism of action remains poorly understood. Consequently, in the present study, this mechanism was thoroughly evaluated employing a dementia mice model, specifically the senescence-accelerated mouse prone 8. The mice were exposed to a mixture of lemon and rosemary oil at nighttime as well as to a mixture of lavender and orange oil in the daytime for 2 months. The cognitive function of the mice was assessed before and after treatment with the aromatic essential oils using the Y-maze test. Moreover, the brain levels of amyloid beta (Aβ), abnormally phosphorylated tau, and brain-derived neurotrophic factor (BDNF) were measured following treatment. The benefits of aromatherapy on the cognitive function in mice were confirmed. It was also established that the brain levels of Aβ and abnormally phosphorylated tau were considerably lower in the aromatherapy group, while the levels of BDNF were marginally higher. These results suggest that aromatherapy employing these aromatic essential oils is beneficial for the prevention and treatment of AD.

Therapeutic effects of rosemary (Rosmarinus officinalis L.) and its active constituents on nervous system disorders

Rosemary (Rosmarinus officinalis L.) is an evergreen bushy shrub which grows along the Mediterranean Sea, and sub-Himalayan areas. In folk medicine, it has been used as an antispasmodic, mild analgesic, to cure intercostal neuralgia, headaches, migraine, insomnia emotional upset, and depression. Different investigations have highlighted rosemary neuropharmacological properties as their main topics. Rosemary has significant antimicrobial, anti-inflammatory, anti-oxidant, anti-apoptotic, anti-tumorigenic, antinociceptive, and neuroprotective properties. Furthermore, it shows important clinical effects on mood, learning, memory, pain, anxiety, and sleep. The aim of the current work is to review the potential neuropharmacological effects of different rosemary extracts and its active constituents on nervous system disorders, their relevant mechanisms and its preclinical application to recall the therapeutic potential of this herb and more directions of future research projects. The data were gathered by searching the English articles in PubMed, Scopus, Google Scholar, and Web of Science. The keywords used as search terms were 'Rosmarinus officinalis', 'rosemary', 'nervous system', 'depression', 'memory', 'Alzheimer's disease' 'epilepsy', 'addiction', 'neuropathic pain', and 'disorders'. All kinds of related articles, abstracts and books were included. No time limitation was considered. Both in vitro and in vivo studies were subjected to this investigation. This review authenticates that rosemary has appeared as a worthy source for curing inflammation, analgesic, anti-anxiety, and memory boosting. It also arranges new perception for further investigations on isolated constituents, especially carnosic acid, rosmarinic acid, and essential oil to find exquisite therapeutics and support drug discovery with fewer side effects to help people suffering from nervous system disorders.

Rosemary extract increases neuronal cell glucose uptake and activates AMPK

Glucose is the primary metabolic substrate of neurons and is responsible for supporting many vital functions including neuronal signalling. Decreases in glucose uptake and utilization are common characteristics of dementia, particularly Alzheimer's disease, and thus agents that can restore neuronal glucose availability may be especially valuable to the field. Diets rich in antioxidants and polyphenols have been associated with reductions in the risk of chronic disease that are associated with aging. In previous studies, rosemary extract (RE) has been reported to have antioxidant, anti-inflammatory, anticancer, and antidiabetic properties. The purpose of the present study was to explore the effects of RE on neuronal glucose uptake. Human SH-SY5Y neuroblastoma cells exposed to varied concentrations of RE showed a dose-dependent increase in glucose uptake, with a significant increase observed following treatment with 5 µg/mL RE for 2 h (159% ± 20.81% of control) that was comparable to maximum insulin stimulation (135.6% ± 3.2% of control). This increase in glucose uptake was paralleled by increases in AMP-activated protein kinase (AMPK), but not Akt, phosphorylation/activation. The present study is the first to report that treatment with rosemary extract can stimulate glucose uptake in a neuronal cell line. These results demonstrate the potential of RE to be used as an agent to regulate neuronal glucose homeostasis. Novelty: RE increases neuronal glucose uptake. RE activates AMPK in neurons. RE increases neuronal glucose uptake independently of insulin signalling.

Potential Role of Phenolic Extracts of Mentha in Managing Oxidative Stress and Alzheimer's Disease

With an increase in the longevity and thus the proportion of the elderly, especially in developed nations, there is a rise in pathological conditions that accompany ageing, such as neurodegenerative disorders. Alzheimer’s disease (AD) is a neurodegenerative disease characterized by progressive cognitive and memory decline. The pathophysiology of the disease is poorly understood, with several factors contributing to its development, such as oxidative stress, neuroinflammation, cholinergic neuronal apoptotic death, and the accumulation of abnormal proteins in the brain. Current medications are only palliative and cannot stop or reverse the progression of the disease. Recent clinical trials of synthetic compounds for the treatment of AD have failed because of their adverse effects or lack of efficacy. Thus, there is impetus behind the search for drugs from natural origins, in addition to the discovery of novel, conventional therapeutics. Mints have been used traditionally for conditions relevant to the central nervous system. Recent studies showed that mint extracts and/or their phenolic constituents have a neuroprotective potential and can target multiple events of AD. In this review, we provide evidence of the potential role of mint extracts and their derivatives as possible sources of treatments in managing AD. Some of the molecular pathways implicated in the development of AD are reviewed, with focus on apoptosis and some redox pathways, pointing to mechanisms that may be modulated for the treatment of AD, and the need for future research invoking knowledge of these pathways is highlighted.

Terpenoids as Potential Geroprotectors

Terpenes and terpenoids are the largest groups of plant secondary metabolites. However, unlike polyphenols, they are rarely associated with geroprotective properties. Here we evaluated the conformity of the biological effects of terpenoids with the criteria of geroprotectors, including primary criteria (lifespan-extending effects in model organisms, improvement of aging biomarkers, low toxicity, minimal adverse effects, improvement of the quality of life) and secondary criteria (evolutionarily conserved mechanisms of action, reproducibility of the effects on different models, prevention of age-associated diseases, increasing of stress-resistance). The number of substances that demonstrate the greatest compliance with both primary and secondary criteria of geroprotectors were found among different classes of terpenoids. Thus, terpenoids are an underestimated source of potential geroprotectors that can effectively influence the mechanisms of aging and age-related diseases.

Erucic acid derived from rosemary regulates differentiation of mesenchymal stem cells into osteoblasts/adipocytes via suppression of peroxisome proliferator-activated receptor γ transcriptional activity

Osteoporosis is associated with increase in fat tissue in bone marrow in humans. Mesenchymal stem cells in bone marrow are induced to differentiate into osteoblasts rather than adipocytes by the stimulation of peroxisome proliferator-activated receptor (PPAR) γ antagonists. PPARγ antagonists are expected to be useful to prevent osteoporosis by regulating the lineages of mesenchymal stem cells in bone marrow, as well as the prevention of obesity. In this study, we explored natural components suppressing PPARγ transcriptional activity in rosemary. Separation of active fraction of rosemary extract by repeated high performance liquid chromatograph and PPARγ luciferase reporter assay identified erucic acid, one of the monounsaturated fatty acids, as an active component. Twenty-five-micrometer erucic acid significantly decreased PPARγ luciferase activity and enhanced the differentiation of mouse-delivered C3H10T1/2 cells into osteoblasts rather than adipocytes. Furthermore, 25-μM erucic acid significantly decreased the expression of adipocyte marker genes, while accelerating osteoblast marker genes. In conclusion, erucic acid is a novel natural component derived from rosemary regulating mesenchymal stem cell differentiation via suppression of PPARγ transcriptional activity.

Can Medicinal Plants and Bioactive Compounds Combat Lipid Peroxidation Product 4-HNE-Induced Deleterious Effects?

The toxic reactive aldehyde 4-hydroxynonenal (4-HNE) belongs to the advanced lipid peroxidation end products. Accumulation of 4-HNE and formation of 4-HNE adducts induced by redox imbalance participate in several cytotoxic processes, which contribute to the pathogenesis and progression of oxidative stress-related human disorders. Medicinal plants and bioactive natural compounds are suggested to be attractive sources of potential agents to mitigate oxidative stress, but little is known about the therapeutic potentials especially on combating 4-HNE-induced deleterious effects. Of note, some investigations clarify the attenuation of medicinal plants and bioactive compounds on 4-HNE-induced disturbances, but strong evidence is needed that these plants and compounds serve as potent agents in the prevention and treatment of disorders driven by 4-HNE. Therefore, this review highlights the pharmacological basis of these medicinal plants and bioactive compounds to combat 4-HNE-induced deleterious effects in oxidative stress-related disorders, such as neurotoxicity and neurological disorder, eye damage, cardiovascular injury, liver injury, and energy metabolism disorder. In addition, this review briefly discusses with special attention to the strategies for developing potential therapies by future applications of these medicinal plants and bioactive compounds, which will help biological and pharmacological scientists to explore the new vistas of medicinal plants in combating 4-HNE-induced deleterious effects.

Analgesic, Anti-inflammatory and In-vitro Hyaluronidase Inhibitory Properties of the Leaf Extract and Solvent Fractions of Otostegia Fruticosa (Forssk.) Schweinf. ex Penzig

Otostegia fruticosa is traditionally used to treat tonsillitis, stomach ache, asthma, arthritis, and febrile illness in different parts of Ethiopia and other countries. In this experiment 70% ethanolic crude extract and fractions of the leaf of Otostegia fruticosa (Forssk.) Schweinf. ex Penzig were evaluated for their in-vivo anti-inflammatory and analgesic activities and in-vitro hyaluronidase inhibition properties at different concentrations. Tail immersion, acetic acid induced writhing and carrageenan-induced paw edema model were used to assess the in-vivo analgesic and anti-inflammatory activities, respectively. Swiss albino mice of either sex were randomly divided into five groups of six mice per group and for evaluation of the fractions randomly divided into six groups of six mice per group. The test groups were treated with hydroalcoholic extract of Otostegia fruticosa (O. fruticosa) at doses of 100, 200, and 400 mg/kg. The positive control groups received either pethidine 5 mg/kg or aspirin at 100 mg/kg or 150 mg/kg. The negative control groups were orally given sunflower oil. All the fractions were administered at the dose of 400 mg/kg. In all models, the higher dose (400 mg/kg) of the crude extract and chloroform fraction showed a significant central and peripheral analgesic and anti-inflammatory activities with comparable effects to standards used. The hyaluronidase inhibition assay result showed that the test samples displayed concentration-dependent inhibitory activities. These findings indicate that 70% ethanol extract and organic solvent fractions of O. fruticosa leaves have potential analgesic, anti-inflammatory, and enzyme inhibitory activities.

A Polyphenolic Complex Attenuates Inflammatory Response and Blood- Brain Barrier Disruption

BACKGROUND

Cerebral ischemia causes a strong inflammatory response. Neumentix is a dietary supplement containing 14.9% rosmarinic acid and 29.9% total phenolic content, which has been proved to be beneficial against inflammatory response. Therefore, Neumentix's effect on anti-inflammatory and blood brain barrier (BBB) disruption in transient middle cerebral artery occlusion (tMCAO) model mice is investigated in this study.

METHODS

After the pretreatment of vehicle or Neumentix 134 mg/kg/d, intraperitoneal injection (i.p.) (containing rosmarinic acid 20 mg/kg/d) for 14 days, mice were subjected to tMCAO for 60 min and kept receiving vehicle or Neumentix daily 5 days afterward.

RESULTS

Neumentix treatment ameliorated neurobehavioral impairment in the corner test (5d after tMCAO, **P<0.01), reduced infarct volume (#P<0.05), suppressed expression of ionized calciumbinding adapter molecule-1 (Iba-1), tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) (###P<0.001), and improved the integrity of BBB (§P<0.05) at 5 days after tMCAO.

CONCLUSION

The present study provided an evidence of Neumentix's anti-inflammatory and neuroprotection effect against BBB disruption on experimental tMCAO model mice, suggesting that Neumentix could be a potential therapeutic agent for stroke.

Cho W, Martins N. Therapeutic Potential of Rosmarinic Acid: A Comprehensive Review

Naturally occurring food-derived active ingredients have received huge attention for their chemopreventive and chemotherapy capabilities in several diseases. Rosmarinic acid (RA) is a caffeic acid ester and a naturally-occurring phenolic compound in a number of plants belonging to the Lamiaceae family, such as Rosmarinus officinalis (rosemary) from which it was formerly isolated. RA intervenes in carcinogenesis through different ways, including in tumor cell proliferation, apoptosis, metastasis, and inflammation. On the other hand, it also exerts powerful antimicrobial, anti-inflammatory, antioxidant and even antidepressant, anti-aging effects. The present review aims to provide an overview on anticancer activities of RA and to deliberate its therapeutic potential against a wide variety of diseases. Given the current evidence, RA may be considered as part of the daily diet in the treatment of several diseases, with pre-determined doses avoiding cytotoxicity.

Icariin Delays Brain Aging in Senescence-Accelerated Mouse Prone 8 (SAMP8) Model via Inhibiting Autophagy

Icariin (ICA), a major flavonoid extracted from the Chinese tonic herb Epimedium, exerts beneficial effects in a variety of age-dependent diseases, such as Alzheimer's disease (AD). However, the antiaging mechanisms remain unclear. The senescence-accelerated mouse-prone 8 (SAMP8) model has been used to study age-related neurodegenerative changes associated with aging and the pathogenesis of AD. Hence, the current study was designed to examine the effect of ICA on age-related cognitive decline in SAMP8 mice and explore the role of autophagy in the ICA-mediated neuroprotection. SAMP8 mice were administered with ICA starting at 5 months of age, and the treatment lasted for 3 consecutive months. Morris water maze was used to evaluate cognitive function. The senescence-associated β-galactosidase staining was used to determine the number of senescence cells. The neuronal morphologic changes were examined via Nissl staining. The hippocampal neuronal ultrastructure was examined by transmission electron microscopy. The expression of autophagy protein was examined by Western blot. ICA-treated SAMP8 mice exhibited a robust improvement in spatial learning and memory function. Meanwhile, ICA reduced the number of senescence cells in the brains of SAMP8 mice, inhibited neuronal loss, and reversed neuronal structural changes in the hippocampi of SAMP8 mice. Moreover, ICA treatment also decreased the formation of autophagosomes in the hippocampus of SAMP8 mice, and reduced the expression of autophagy-related proteins LC3-II and p62. These results demonstrate that ICA possesses the ability to delay brain aging in SAMP8 mice, and the mechanisms are possibly mediated through the regulation of autophagy.

An Overview of Cognitive Impairment

Cognitive decline occurs in all persons during the aging process. Eventually, this can result in mild cognitive impairment and dementia. There are more than 100 causes of dementia. A multifocal approach to slowing cognitive decline (Mediterranean diet, exercise, computer games, socialization, and treatment of cardiovascular risk factors) appears to be effective.

Spearmint Extract Improves Working Memory in Men and Women with Age-Associated Memory Impairment

OBJECTIVE

The purpose of this study was to investigate the effects of supplementation with a spearmint (Mentha spicata L.) extract, high in polyphenols including rosmarinic acid, on cognitive performance, sleep, and mood in individuals with age-associated memory impairment (AAMI).

DESIGN

Subjects with AAMI (N = 90; 67% female; age = 59.4 ± 0.6 years) were randomly assigned (n = 30/group) to consume 900, 600, or 0 mg/day (two capsules, once daily) spearmint extract for 90 days, in this double-blind, placebo-controlled trial. Assessments were completed for cognition (days 0, 45, and 90), sleep (days 0 and 90), and mood (days 0 and 90) by using the Cognitive Drug Research (CDR) System™, Leeds Sleep Evaluation Questionnaire (LSEQ), and Profile of Mood States (POMS™), respectively.

RESULTS

Quality of working memory and spatial working memory accuracy improved after supplementation with 900 mg/day spearmint extract by 15% (p = 0.0469) and 9% (p = 0.0456), respectively, versus placebo. Subjects consuming 900 mg/day spearmint extract reported improvement in their ability to fall asleep, relative to subjects consuming placebo (p = 0.0046). Overall treatment effects were evident for vigor-activity (p = 0.0399), total mood disturbance (p = 0.0374), and alertness and behavior following wakefulness (p = 0.0415), with trends observed for improvements after spearmint supplementation relative to placebo.

CONCLUSIONS

These results suggest that the distinct spearmint extract may be a beneficial nutritional intervention for cognitive health in older subjects with AAMI.

Cognitive-enhancing and antioxidant activities of the aqueous extract from Markhamia tomentosa (Benth.) K. Schum. stem bark in a rat model of scopolamine

BACKGROUND

Plants of the genus Markhamia have been traditionally used by different tribes in various parts of West African countries, including Cameroun. Markhamia tomentosa (Benth.) K. Schum. (Bignoniaceae) is used as an antimalarial, anti-inflammatory, analgesic, antioxidant and anti-Alzheimer agent. The current study was undertaken in order to investigate its anti-amnesic and antioxidant potential on scopolamine-induced cognitive impairment and to determine its possible mechanism of action.

METHODS

Rats were pretreated with the aqueous extract (50 and 200 mg/kg, p.o.), for 10 days, and received a single injection of scopolamine (0.7 mg/kg, i.p.) before training in Y-maze and radial arm-maze tests. The biochemical parameters in the rat hippocampus were also assessed to explore oxidative status. Statistical analyses were performed using two-way ANOVA followed by Tukey's post hoc test. F values for which p < 0.05 were regarded as statistically significant.

RESULTS

In the scopolamine-treated rats, the aqueous extract improved memory in behavioral tests and decreased the oxidative stress in the rat hippocampus. Also, the aqueous extract exhibited anti-acetylcholinesterase activity.

CONCLUSIONS

These results suggest that the aqueous extract ameliorates scopolamine-induced spatial memory impairment by attenuation of the oxidative stress in the rat hippocampus.

Safety and tolerability of a dried aqueous spearmint extract

Spearmint (Mentha spicata L.) and spearmint extracts are Generally Recognized as Safe (GRAS) for use as flavoring in beverages, pharmaceuticals, and confectionaries. Studies of spearmint extracts in humans and animals have reported conflicting results with respect to toxicity. Since the chemical composition of these extracts was not reported and the spearmint source material was different, the relevance of these existing data to evaluating the risks associated with ingestion of a dried aqueous spearmint extract standardized to rosmarinic acid is not clear. Hence, the safety and tolerability of the dried aqueous spearmint extract was evaluated as part of a double-blind, randomized, placebo-controlled trial in healthy adults with age-associated memory impairment. Ingestion of both 600 and 900 mg/day for 90 days had no effect on plasma levels of follicular stimulating hormone, luteinizing hormone, or thyroid stimulating hormone, or other safety parameters including vital signs, plasma chemistry or whole blood hematology values. Additionally, there were no reported severe adverse events, no significant between-group differences in the number of subjects reporting adverse effects and the adverse events reported could not be attributed to ingestion of the extract. These results therefore show that ingestion of the aqueous dried spearmint extract is safe and well-tolerated.

Effect of the oral administration of nanoencapsulated quercetin on a mouse model of Alzheimer's disease

Quercetin has been identified as a promising compound with a neuroprotective potential against age-related neurodegenerative diseases such as Alzheimer's disease (AD). Nevertheless, the clinical application of quercetin is hampered by its low oral bioavailability. The aim of this work was to evaluate the capability of nanoencapsulated quercetin in zein nanoparticles (NPQ), that significantly improves the oral absorption and bioavailability of the flavonoid, as potential oral treatment for AD. For this purpose, SAMP8 mice were orally treated for two months with either NPQ (25mg/kg every 48h) or a solution of quercetin (Q; 25mg/kg daily). NPQ displayed a size of 260nm and a payload of about 70μg/mg. For Q, no significant effects were observed in animals. On the contrary, the oral administration of NPQ improved the cognition and memory impairments characteristics of SAMP8 mice. These observations appeared to be related with a decreased expression of the hippocampal astrocyte marker GFAP. Furthermore, significant levels of quercetin were quantified in the brain of mice treated with nanoparticles. These findings highlight the potential of zein nanoparticles to promote the oral absorption of quercetin as well as the therapeutic potential of this flavonoid in AD pathogenesis.