Ethnopharmacological Approaches for Dementia Therapy and Significance of Natural Products and Herbal Drugs

Ginkgo biloba extract safety: Insights from a real-world pharmacovigilance study of FDA adverse event reporting system (FAERS) events

ETHNOPHARMACOLOGICAL RELEVANCE

A traditional Chinese medicine extracted from the Ginkgophyta, Ginkgo biloba is commonly used to treat cardiac cerebral disease all over the world. Limited data exist regarding adverse drug reactions associated with Ginkgo biloba extract post-marketing.

AIM OF THE STUDY

Currently, the drug safety profile of Ginkgo biloba extract is assessed using a substantial volume of case safety reports within the FDA Adverse Event Reporting System (FAERS) database.

MATERIALS AND METHODS

The study collected adverse events (AEs) data associated with Ginkgo biloba extract as the primary suspected drug from 2004 to 2023 from the FAERS database. A standardized mapping analysis of System Organ Class (SOC) and preferred term (PT) was conducted. Utilizing reporting odds ratio (ROR), proportional reporting ratio (PRR), information component (IC), and empirical Bayes geometric mean (EBGM), significant disproportionate measurement signals of adverse drug reactions (ADR) were identified and high-intensity signals were analyzed.

RESULTS

700 reports of adverse events related to Ginkgo biloba extract were found in the FAERS database, affecting 23 organ systems. 88 significant mismatches were identified using four algorithms, leading to unexpected major adverse events like amaurosis fugax, fractional exhaled nitric oxide created, and obstructive sleep apnoea syndrome. The study observed a median onset time of AE associated with Ginkgo biloba extract at 7 days (interquartile interval [IQR] 0-109 days), with the majority of AE manifesting within the initial 7 days of drug treatment initiation. This investigation identified a noteworthy AE signal for Ginkgo biloba extract, underscoring the importance of clinical surveillance and risk assessment in its use.

CONCLUSIONS

In clinical practice, this study provides a deeper and broader understanding of suspected adverse reactions associated with Ginkgo biloba extract.

Proteostasis Decline and Redox Imbalance in Age-Related Diseases: The Therapeutic Potential of NRF2

Nuclear factor erythroid 2-related factor 2 (NRF2) is a master regulator of cellular homeostasis, overseeing the expression of a wide array of genes involved in cytoprotective processes such as antioxidant and proteostasis control, mitochondrial function, inflammation, and the metabolism of lipids and glucose. The accumulation of misfolded proteins triggers the release, stabilization, and nuclear translocation of NRF2, which in turn enhances the expression of critical components of both the proteasomal and lysosomal degradation pathways. This process facilitates the clearance of toxic protein aggregates, thereby actively maintaining cellular proteostasis. As we age, the efficiency of the NRF2 pathway declines due to several factors including increased activity of its repressors, impaired NRF2-mediated antioxidant and cytoprotective gene expression, and potential epigenetic changes, though the precise mechanisms remain unclear. This leads to diminished antioxidant defenses, increased oxidative damage, and exacerbated metabolic dysregulation and inflammation-key contributors to age-related diseases. Given NRF2's role in mitigating proteotoxic stress, the pharmacological modulation of NRF2 has emerged as a promising therapeutic strategy, even in aged preclinical models. By inducing NRF2, it is possible to mitigate the damaging effects of oxidative stress, metabolic dysfunction, and inflammation, thus reducing protein misfolding. The review highlights NRF2's therapeutic implications for neurodegenerative diseases and cardiovascular conditions, emphasizing its role in improving proteostasis and redox homeostasis Additionally, it summarizes current research into NRF2 as a therapeutic target, offering hope for innovative treatments to counteract the effects of aging and associated diseases.

Plant and marine-derived natural products: sustainable pathways for future drug discovery and therapeutic development

Plant- and marine-derived natural products are rich sources of bioactive compounds essential for drug discovery. These compounds contain complex mixtures of metabolites, which collectively contribute to their pharmacological properties. However, challenges arise in the isolation of individual bioactive compounds, owing to their intricate chemistry and low abundance in natural extracts. Despite these limitations, numerous plant and marine-derived compounds have achieved regulatory approval, particularly for treating cancer and infectious diseases. This review explores the therapeutic potential of plant and marine sources along with innovative extraction and isolation methods that support sustainable drug development. Future perspectives will highlight the role of responsible innovation, artificial intelligence, and machine learning in advancing drug discovery, underscoring the importance of continued research to meet global health needs.

Ellagic acid ameliorates alcohol-induced cognitive and social dysfunction through the gut microbiota-mediated CCL21-CCR7 axis

Chronic alcohol consumption disrupts the balance of the gut microbiome, resulting in alcohol-induced cognitive and social dysfunction (AICSD), and serves as a primary etiological factor for early-onset dementia. Ellagic acid (EA) is a polyphenolic compound belonging to the ellagitannin family, showing potential as a dietary intervention for alleviating cognitive impairments. Nonetheless, the protective effects and underlying mechanisms of EA on AICSD remain unclear. In our study, we employed a multi-omics approach to elucidate the microbiome-mediated mechanism underlying the beneficial effects of EA on AICSD. Firstly, our findings demonstrate that EA significantly ameliorated cognitive and social behavioral deficits as well as neuroinflammation induced by alcohol. Moreover, RNA-seq analysis of hippocampi indicates that EA regulated the KEGG pathway of cytokine-cytokine receptor interaction signaling by downregulating the CCL21-CCR7 axis. Furthermore, we observed that EA effectively restored the dysbiosis of gut microbiota and their derived metabolites induced by chronic alcohol consumption. Strong connections were observed between EA-regulated genes, microbiota and metabolites. Finally, the causal relationship between the microbiome and behavioral changes was further confirmed through antibiotic treatment and fecal microbiota transplantation experiments. Overall, our study provides innovative evidence supporting the role of EA in improving AICSD via regulation of the cytokine-cytokine receptor interaction signaling pathway through the microbiota-mediated CCl21-CCR7 axis. These findings offer valuable insights into both EA-based interventions as well as microbial interventions against AICSD.

Signaling Pathways Concerning Mitochondrial Dysfunction: Implications in Neurodegeneration and Possible Molecular Targets

Mitochondrion is an important organelle present in our cells responsible for meeting energy requirements. All higher organisms rely on efficient mitochondrial bioenergetic machinery to sustain life. No other respiratory process can produce as much power as generated by mitochondria in the form of ATPs. This review is written in order to get an insight into the magnificent working of mitochondrion and its implications in cellular homeostasis, bioenergetics, redox, calcium signaling, and cell death. However, if this machinery gets faulty, it may lead to several disease states. Mitochondrial dysfunctioning is of growing concern today as it is seen in the pathogenesis of several diseases which includes neurodegenerative disorders, cardiovascular disorders, diabetes mellitus, skeletal muscle defects, liver diseases, and so on. To cover all these aspects is beyond the scope of this article; hence, our study is restricted to neurodegenerative disorders only. Moreover, faulty functioning of this organelle can be one of the causes of early ageing in individuals. This review emphasizes mutations in the mitochondrial DNA, defects in oxidative phosphorylation, generation of ROS, and apoptosis. Researchers have looked into new approaches that might be able to control mitochondrial failure and show a lot of promise as treatments.

Pomegranate polyphenol punicalagin as a nutraceutical for mitigating mild cognitive impairment: An overview of beneficial properties

Dementia treatment has become a global research priority, driven by the increase in the aging population. Punicalagin, the primary polyphenol found in pomegranate fruit, exhibits a variety of benefits. Today, a growing body of research is showing that punicalagin is a nutraceutical for the prevention of mild cognitive impairment (MCI). However, a comprehensive review is still lacking. The aim of this paper is to provide a comprehensive review of the physicochemical properties, origin and pharmacokinetics of punicalagin, while emphasizing the significance and mechanisms of its potential role in the prevention and treatment of MCI. Preclinical and clinical studies have demonstrated that Punicalagin possesses the potential to effectively target and enhance the treatment of MCI. Potential mechanisms by which punicalagin alleviates MCI include antioxidative damage, anti-neuroinflammation, promotion of neurogenesis, and modulation of neurotransmitter interactions. Overall, punicalagin is safer and shows potential as a therapeutic compound for the prevention and treatment of MCI, although more rigorous randomized controlled trials involving large populations are required.

Biological Activities of Galanthus fosteri Extracts: First Demonstration of the Interaction between Chlorogenic Acid and DNA Ligase by Molecular Docking

Within the Amaryllidaceae family, the bulbous plant species Galanthus fosteri (G. fosteri) belongs to the Galanthus genus. Alkaloids with a broad variety of biological functions are typically found in the flora of this family. The G. fosteri plant's organs' antioxidant activity, antibacterial impact, and antimicrobial qualities were examined in this study. Total flavonoid contents (TFC) and total phenolic contents (TPC) of plant extracts were measured with spectrophotometric methods, and antioxidant activity was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging technique. The HPLC method was used to determine the phenolic compounds on a component basis. The antibacterial properties of the extracts were assessed using the Kirby-Bauer disc diffusion method, and the minimum inhibitory concentration method against the pathogens Klebsiella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Additionally, combination tests were performed between the extract and antibiotics. Leaf and stem extracts demonstrated greater antioxidant qualities than bulb extracts, despite the fact that extracts of plant organs did not exhibit appreciable levels of TPC, TFC, or antioxidant qualities. According to the HPLC analysis results, it was determined that chlorogenic acid was present in all of the extracts. In fact, it was determined that only chlorogenic acid was 8.02 (mg/10 g) in G. fosteri bulb peel, which has antimicrobial and antioxidant properties. A molecular docking study has demonstrated for the first time that the antibacterial effect of chlorogenic acid might be due to DNA replication inhibition.

Mechanism of action of certain medicinal plants for the treatment of asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Asthma is often treated and prevented using the pharmacological properties of traditional medicinal plants. These healthcare systems are among the most well-known, conveniently accessible, and economically priced in India and several other Asian countries. Traditional Indian Ayurvedic plants have the potential to be used as phyto-therapeutics, to create novel anti-asthmatic drugs, and as a cost-effective source of pharmaceuticals. Current conventional therapies have drawbacks, including serious side effects and expensive costs that interfere with treatment compliance and affect the patient's quality of life. The primary objective of the article is to comprehensively evaluate the advancement of research on the protective phytochemicals of traditional plants that target immune responses and signaling cascades in inflammatory experimental asthma models. The study would assist in paving the way for the creation of natural phytomedicines that are protective, anti-inflammatory, and immunomodulatory against asthma, which may then be used in individualized asthma therapy.

AIM OF THE STUDY

The study demonstrates the mechanisms of action of phytochemicals present in traditional medicinal plants, diminish pulmonary disorder in both in vivo and in vitro models of asthma.

MATERIALS AND METHODS

A comprehensive review of the literature on conventional plant-based asthma therapies was performed from 2006 to 2022. The study uses authoritative scientific sources such as PubMed, PubChem Compound, Wiley Online Library, Science Direct, Springer Link, and Google Scholar to collect information on potential phytochemicals and their mechanisms of action. World Flora Online (http://www.worldfloraonline.org) and Plants of the World Online (https://wcsp.science.kew.org) databases were used for the scientific names of medicinal plants.

RESULTS

The study outlines the phytochemical mechanisms of some traditional Ayurveda botanicals used to treat asthma. Active phytochemicals including curcumin, withaferin-A, piperine, glabridin, glycyrrhizin, 18β-glycyrrhetinic acid, trans-cinnamaldehyde, α-hederin, thymoquinone, eugenol, [6]-shogoal, and gingerol may treat asthma by controlling inflammation and airway remodeling. The study concluded that certain Ayurvedic plants' phytochemicals have the ability to reduce inflammation and modulate the immune system, that can effectively cure asthma.

CONCLUSION

Plants used in traditional Ayurvedic medicine have been utilized for millennia, advocating phyto-therapy as a treatment for a variety of illnesses. A theoretical foundation for the use of cutting-edge asthma treatments has been built with the growth of experimental research on traditional phytochemicals. In-depth phytochemical research for the treatment of asthma using Indian Traditional Ayurvedic herbs is compiled in the study. The approach for preventative therapeutics and cutting-edge alternatives to battle the molecular pathways in the pathophysiology of asthma are the key themes of the study. The phytochemical mechanism of action of traditional Ayurvedic herbs is explained to get the attention of the pharmaceutical industry so they can make future anti-asthma drugs for personalized asthma care in the community. The study develops strategies for customized phyto-therapeutics, concentrating on low-cost, side-effect-free approaches that employ bioactive phytochemicals from plants as the major source of effective anti-asthmatic therapy.

Acetylcholinesterase Inhibition Activity of Hippeastrum papilio (Ravenna) Van Scheepen (Amaryllidaceae) Using Zebrafish Brain Homogenates

The Amaryllidaceae family constitutes an interesting source of exclusive alkaloids with a broad spectrum of biological activity. Galanthamine, the most relevant one, has been commercialized for the palliative treatment of Alzheimer's disease symptoms since 2001 due to its potential as an acetylcholinesterase (AChE) inhibitor. In vitro screenings against AChE by applying different Amaryllidaceae species and alkaloids have been reported in the literature; however, they are usually carried out using purified market enzymes. The main goal of this work is to evaluate the AChE inhibitory potential of Hippeastrum papilio (Amaryllidaceae) extracts using zebrafish brain homogenates. The biological assays show that the H. papilio bulb extracts present an interesting AChE inhibitory activity in comparison with the positive reference control galanthamine (IC50 values of 1.20 ± 0.10 and 0.79 ± 0.15 μg/mL, respectively). The chemical profile of H. papilio shows that this species has a high amount of galanthamine, which may contribute to the inhibitory effect on AChE activity of zebrafish brains. Computational experiments were used to build the model for zebrafish AChE and to evaluate the interactions between galanthamine and the enzymic active site. This work suggests that zebrafish could represent an important model in the search for bioactive molecules from the Amaryllidaceae family for the treatment of Alzheimer's disease.

Rosmarinic Acid Improves Cognitive Abilities and Glucose Metabolism in Aged C57Bl/6N Mice While Disrupting Lipid Profile in Young Adults in a Sex-Dependent Fashion

A growing body of evidence suggests that regular consumption of natural products might promote healthy aging; however, their mechanisms of action are still unclear. Rosmarinic acid (RA) is a polyphenol holding anti-inflammatory, antioxidant and neuroprotective properties. The aim of this study was to characterise the efficacy of an oral administration of RA in promoting healthspan in a mouse model of physiological aging. Aged C57Bl/6 male and female (24-month-old) mice were either administered with RA (500 mg/Kg) or a vehicle in drinking bottles for 52 days while 3-month-old mice receiving the same treatment were used as controls. All subjects were assessed for cognitive abilities in the Morris water maze (MWM) and for emotionality in the elevated-plus maze test (EPM). Brain-derived Neurotrophic Factor (BDNF) protein levels were evaluated in the hippocampus. Since the interaction between metabolic signals and cerebral functions plays a pivotal role in the etiopathogenesis of cognitive decline, the glycaemic and lipid profiles of the mice were also assessed. RA enhanced learning and memory in 24-month-old mice, an effect that was associated to improved glucose homeostasis. By contrast, the lipid profile was disrupted in young adults. This effect was associated with worse glycaemic control in males and with reduced BDNF levels in females, suggesting powerful sex-dependent effects and raising a note of caution for RA administration in young healthy adult subjects.

Protective Effect of Galantamine against Doxorubicin-Induced Neurotoxicity

BACKGROUND AND AIMS

Doxorubicin (DOX) causes cognitive impairment (chemobrain) in patients with cancer. While DOX damages the cholinergic system, few studies have focused on the protective effects of cholinergic function on chemobrain. The acetylcholinesterase inhibitor galantamine (GAL) demonstrates neuroprotective properties. We investigated the mechanisms associated with DOX-induced cognitive impairments and the potential protective role of GAL in preventing chemobrain.

MAIN METHODS

Female Wistar rats were divided into control, DOX, GAL, and DOX + GAL groups. The rats in the DOX group were administered DOX (5 mg/kg intraperitoneally twice weekly for two weeks), while those in the GAL group were orally administered GAL (2.5 mg/kg) via oral gavage once daily for 15 days. The combination group (DOX + GAL) received GAL (once daily) and DOX (two times per week) concurrently. The body weights and survival rates were monitored daily. The animals were subjected to behavioral tests to assess the memory function followed by the biochemical estimation of inflammatory markers, including tumor necrosis factor-α (TNF-α), interleukine-1β (IL-1β), and interleukine-6 (IL-6) in rat brain tissue and RT-qPCR.

KEY FINDINGS

DOX caused a reduction in the body weight and survival rate, which was alleviated by GAL concomitant treatment with DOX (DOX + GAL). These groups had reduced body weights and survival rates. DOX-treated animals exhibited an impairment of short-term spatial working memory, manifested as a behavioral alteration in the Y-maze test, the novel object recognition (NOR) test, and the elevated plus-maze (EPM) test. Concurrent treatment with GAL (DOX + GAL) showed improved memory function, as evidenced by an increase in the number of entries and time spent in the novel arm, the time spent exploring the novel object, and the transfer latency in the Y-maze, NOR test, and EPM test, respectively. These findings were also supported by biochemical observations showing the reversal of DOX-induced changes in IL-1β, IL-6, and TNF-α, as well as their relative expression of mRNA in brain tissue following concurrent GAL treatment.

CONCLUSION

GAL appeared to be a neuroprotective agent against neuroinflammation caused by DOX by reducing inflammatory markers in the brain.

The Formation of Volume Transmission Gratings in Acrylamide-Based Photopolymers Using Curcumin as a Long-Wavelength Photosensitizer

Curcumin, a natural dye found in the Curcuma longa rhizome, commonly called turmeric, is used as a photosensitizer in acrylamide-based photopolymers for holographic data storage. We studied the absorbance of photopolymer films that show two absorption bands due to curcumin, acrylamide monomer (AA), and the crosslinking agent N,N'-methylenebisacrylamide (MBA). Analysis of the real-time diffraction efficiency of these films shows a maximum of 16% for the sample with the highest curcumin concentration. Moreover, increasing the curcumin load enhanced the refractive index contrast from 7.8 × 10^-4 for the photopolymer with the lowest curcumin load to 1.1 × 10^-3 for the photopolymer with the largest load. The sensitivity and diffraction efficiency of the recorded gratings also increased from 7.0 to 9.8 cm·J^-1 and from 7.9 to 16% with the increase in curcumin load, respectively. Finally, the influence of NaOH on the photopolymerization of the AA-curcumin-based sample shows a diffraction efficiency increase with the NaOH content, revealing that the curcumin enol form is more efficient as a photosensitizer.

Highly selective butyrylcholinesterase inhibitors related to Amaryllidaceae alkaloids - Design, synthesis, and biological evaluation

Butyrylcholinesterase (BChE) is one of the most frequently implicated enzymes in the advanced stage of Alzheimer's disease (AD). As part of our endeavors to develop new drug candidates for AD, we have focused on natural template structures, namely the Amaryllidaceae alkaloids carltonine A and B endowed with high BChE selectivity. Herein, we report the design, synthesis, and in vitro evaluation of 57 novel highly selective human BChE (hBChE) inhibitors. Most synthesized compounds showed hBChE inhibition potency ranging from micromolar to low nanomolar scale. Compounds that revealed BChE inhibition below 100 nM were selected for detailed biological investigation. The CNS-targeted profile of the presented compounds was confirmed theoretically by calculating the BBB score algorithm, these data were corroborated by determining the permeability in vitro using PAMPA-assay for the most active derivatives. The study highlighted compounds 87 (hBChE IC₅₀ = 3.8 ± 0.2 nM) and 88 (hBChE IC₅₀ = 5.7 ± 1.5 nM) as the top-ranked BChE inhibitors. Compounds revealed negligible cytotoxicity for the human neuroblastoma (SH-SY5Y) and hepatocellular carcinoma (HepG2) cell lines compared to BChE inhibitory potential. A crystallographic study was performed to inspect the binding mode of compound 87, revealing essential interactions between 87 and hBChE active site. In addition, multidimensional QSAR analyses were applied to determine the relationship between chemical structures and biological activity in a dataset of designed agents. Compound 87 is a promising lead compound with potential implications for treating the late stages of AD.

Kai-Xin-San protects against mitochondrial dysfunction in Alzheimer's disease through SIRT3/NLRP3 pathway

BACKGROUND

Kai-Xin-San (KXS) has been reported to have a good curative impact on dementia. The purpose of the study was to determine whether KXS might ameliorate cognitive deficits in APP/PS1 mice and to evaluate its neuroprotective mechanism.

METHODS

APP/PS1 mice were employed as an AD animal model; Aβ_1-42 and KXS-containing serum were used in HT22 cells. Four different behavioral tests were used to determine the cognitive ability of mice. Nissl staining was utilized to detect hippocampal neuron changes. ROS, SOD, and MDA were used to detect oxidative stress levels. Transmission electron microscopy and Western blot were used to evaluate mitochondrial morphology, mitochondrial division, and fusion state. Western blotting and immunofluorescence identified PSD95, BDNF, NGF, SYN, SIRT3, and NLRP3 inflammasome levels.

RESULTS

The results indicated that KXS protected APP/PS1 mice against cognitive impairments. KXS suppressed neuronal apoptosis and oxidative stress among APP/PS1 mice. KXS and KXS-containing serum improved mitochondrial dysfunction and synaptic and neurotrophic factors regarding APP/PS1 mice. In addition, KXS and KXS-containing serum enhanced mitochondrial SIRT3 expression and reduced NLRP3 inflammasome expression in APP/PS1 mice.

CONCLUSION

KXS improves cognitive dysfunction among APP/PS1 mice via regulating SIRT3-mediated neuronal cell apoptosis. These results suggested that KXS was proposed as a neuroprotective agent for AD progression.

Phytotherapeutic alternatives for neurodegenerative dementias: Scientific review, discussion and therapeutic proposal

The incidence and prevalence of age-related neurodegenerative dementias have been increasing. There is no curative therapy and conventional drug treatment can cause problems for patients. Medicinal plants traditionally used for problems associated with ageing are emerging as a therapeutic resource. The main aim is to give a proposal for use and future research based on scientific knowledge and tradition. A literature search was conducted in several searchable databases. The keywords used were related to neurodegenerative dementias, ageing and medicinal plants. Boolean operators and filters were used to focus the search. As a result, there is current clinical and preclinical scientific information on 49 species used in traditional medicine for ageing-related problems, including neurodegenerative dementias. There are preclinical and clinical scientific evidences on their properties against protein aggregates in the central nervous system and their effects on neuroinflammation, apoptosis dysregulation, mitochondrial dysfunction, gabaergic, glutamatergic and dopaminergic systems alterations, monoamine oxidase alterations, serotonin depletion and oestrogenic protection. In conclusion, the potential therapeutic effect of the different medicinal plants depends on the type of neurodegenerative dementia and its stage of development, but more clinical and preclinical research is needed to find better, safer and more effective treatments.

The International Natural Product Sciences Taskforce (INPST) and the power of Twitter networking exemplified through #INPST hashtag analysis

BACKGROUND

The development of digital technologies and the evolution of open innovation approaches have enabled the creation of diverse virtual organizations and enterprises coordinating their activities primarily online. The open innovation platform titled "International Natural Product Sciences Taskforce" (INPST) was established in 2018, to bring together in collaborative environment individuals and organizations interested in natural product scientific research, and to empower their interactions by using digital communication tools.

METHODS

In this work, we present a general overview of INPST activities and showcase the specific use of Twitter as a powerful networking tool that was used to host a one-week "2021 INPST Twitter Networking Event" (spanning from 31st May 2021 to 6th June 2021) based on the application of the Twitter hashtag #INPST.

RESULTS AND CONCLUSION

The use of this hashtag during the networking event period was analyzed with Symplur Signals (https://www.symplur.com/), revealing a total of 6,036 tweets, shared by 686 users, which generated a total of 65,004,773 impressions (views of the respective tweets). This networking event's achieved high visibility and participation rate showcases a convincing example of how this social media platform can be used as a highly effective tool to host virtual Twitter-based international biomedical research events.

Bazi Bushen capsule attenuates cognitive deficits by inhibiting microglia activation and cellular senescence

CONTEXT

Bazi Bushen capsule (BZBS) has anti-ageing properties and is effective in enhancing memory.

OBJECTIVE

To find evidence supporting the mechanisms and biomarkers by which BZBS functions.

MATERIALS AND METHODS

Male C57BL/6J mice were randomly divided into five groups: normal, ageing, β-nicotinamide mononucleotide capsule (NMN), BZBS low-dose (LD-BZ) and BZBS high-dose (HD-BZ). The last four groups were subcutaneously injected with d-galactose (d-gal, 100 mg/kg/d) to induce the ageing process. At the same time, the LD-BZ, HD-BZ and NMN groups were intragastrically injected with BZBS (1 and 2 g/kg/d) and NMN (100 mg/kg/d) for treatment, respectively. After 60 days, the changes in overall ageing status, brain neuron morphology, expression of p16^INK4a, proliferating cell nuclear antigen (PCNA), ionized calcium-binding adapter molecule 1 (Iba1), postsynaptic density protein 95 (PSD95), CD11b, Arg1, CD206, Trem2, Ym1 and Fizz1, and the senescence-associated secretory phenotype (SASP) factors were observed.

RESULTS

Compared with the mice in the ageing group, the HD-BZ mice exhibited obvious improvements in strength, endurance, motor coordination, cognitive function and neuron injury. The results showed a decrease in p16^INK4a, Iba1 and the upregulation of PCNA, PSD95 among brain proteins. The brain mRNA exhibited downregulation of Iba1 (p < 0.001), CD11b (p < 0.001), and upregulation of Arg1 (p < 0.01), CD206 (p < 0.05), Trem2 (p < 0.001), Ym1 (p < 0.01), Fizz1 (p < 0.05) and PSD95 (p < 0.01), as well as improvement of SASP factors.

CONCLUSIONS

BZBS improves cognitive deficits via inhibition of cellular senescence and microglia activation. This study provides experimental evidence for the wide application of BZBS in clinical practice for cognitive deficits.

Systematic Review of the Therapeutic Role of Apoptotic Inhibitors in Neurodegeneration and Their Potential Use in Schizophrenia

Schizophrenia (SZ) is a deleterious brain disorder affecting cognition, emotion and reality perception. The most widely accepted neurochemical-hypothesis is the imbalance of neurotransmitter-systems. Depleted GABAergic-inhibitory function might produce a regionally-located dopaminergic and glutamatergic-storm in the brain. The dopaminergic-release may underlie the positive psychotic-symptoms while the glutamatergic-release could prompt the primary negative symptoms/cognitive deficits. This may occur due to excessive synaptic-pruning during the neurodevelopmental stages of adolescence/early adulthood. Thus, although SZ is not a neurodegenerative disease, it has been suggested that exaggerated dendritic-apoptosis could explain the limited neuroprogression around its onset. This apoptotic nature of SZ highlights the potential therapeutic action of anti-apoptotic drugs, especially at prodromal stages. If dysregulation of apoptotic mechanisms underlies the molecular basis of SZ, then anti-apoptotic molecules could be a prodromal therapeutic option to halt or prevent SZ. In fact, risk alleles related in apoptotic genes have been recently associated to SZ and shared molecular apoptotic changes are common in the main neurodegenerative disorders and SZ. PRISMA-guidelines were considered. Anti-apoptotic drugs are commonly applied in classic neurodegenerative disorders with promising results. Despite both the apoptotic-hallmarks of SZ and the widespread use of anti-apoptotic targets in neurodegeneration, there is a strikingly scarce number of studies investigating anti-apoptotic approaches in SZ. We analyzed the anti-apoptotic approaches conducted in neurodegeneration and the potential applications of such anti-apoptotic therapies as a promising novel therapeutic strategy, especially during early stages.

Plant based food bioactives: A boon or bane for neurological disorders

Neurological disorders are the foremost occurring diseases across the globe resulting in progressive dysfunction, loss of neuronal structure ultimately cell death. Therefore, attention has been drawn toward the natural resources for the search of neuroprotective agents. Plant-based food bioactives have emerged as potential neuroprotective agents for the treatment of neurodegenerative disorders. This comprehensive review primarily focuses on various plant food bioactive, mechanisms, therapeutic targets, in vitro and in vivo studies in the treatment of neurological disorders to explore whether they are boon or bane for neurological disorders. In addition, the clinical perspective of plant food bioactives in neurological disorders are also highlighted. Scientific evidences point toward the enormous therapeutic efficacy of plant food bioactives in the prevention or treatment of neurological disorders. Nevertheless, identification of food bioactive components accountable for the neuroprotective effects, mechanism, clinical trials, and consolidation of information flow are warranted. Plant food bioactives primarily act by mediating through various pathways including oxidative stress, neuroinflammation, apoptosis, excitotoxicity, specific proteins, mitochondrial dysfunction, and reversing neurodegeneration and can be used for the prevention and therapy of neurodegenerative disorders. In conclusion, the plant based food bioactives are boon for neurological disorders.

Effect of methylmercury on fetal neurobehavioral development: an overview of the possible mechanisms of toxicity and the neuroprotective effect of phytochemicals

Methylmercury (MeHg) is a global environmental pollutant with neurotoxic effects. Exposure to MeHg via consumption of seafood and fish can severely impact fetal neurobehavioral development even when MeHg levels in maternal blood are as low as about 5 μg/L, which the mother tolerates well. Persistent motor dysfunctions and cognitive deficits may result from trans-placental exposure. The present review summarizes current knowledge on the mechanisms of MeHg toxicity during the period of nervous system development. Although cerebellar Purkinje cells are MeHg targets, the actions of MeHg on thiol components in the neuronal cytoskeleton as well as on mitochondrial enzymes and induction of disturbances of glutamate signaling can impair extra-cerebellar functions, also at levels well tolerated by adult individuals. Numerous herbal substances possess neuroprotective effects, predominantly represented by natural polyphenolic molecules that might be utilized to develop natural drugs to alleviate neurotoxicity symptoms caused by MeHg or other Hg compounds.

Antioxidant Therapeutic Strategies in Neurodegenerative Diseases

The distinguishing pathogenic features of neurodegenerative diseases include mitochondrial dysfunction and derived reactive oxygen species generation. The neural tissue is highly sensitive to oxidative stress and this is a prominent factor in both chronic and acute neurodegeneration. Based on this, therapeutic strategies using antioxidant molecules towards redox equilibrium have been widely used for the treatment of several brain pathologies. Globally, polyphenols, carotenes and vitamins are among the most typical exogenous antioxidant agents that have been tested in neurodegeneration as adjunctive therapies. However, other types of antioxidants, including hormones, such as the widely used melatonin, are also considered neuroprotective agents and have been used in different neurodegenerative contexts. This review highlights the most relevant mitochondrial antioxidant targets in the main neurodegenerative disorders including Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease and also in the less represented amyotrophic lateral sclerosis, as well as traumatic brain injury, while summarizing the latest randomized placebo-controlled trials.

Ameliorative Processes of Beta-Carotene in Streptozotocin-Induced Diabetic Vascular Dementia in Rats

Beta-carotene (BC) is a precursor of vitamin A and an excellent antioxidant. It protects the vascular system. Vascular dementia (VaD) is one of the aging disorders causing memory dysfunction. The available medicines for the management of VaD are limited. The present study aimed to evaluate the ameliorative effect of BC in streptozotocin (STZ)-induced diabetic VaD in rats. Diabetic VaD was induced through the administration of nicotinamide (NA, 50 mg/kg; i.p.) and STZ (50 mg/kg; i.p.). The test compound BC (50 and 100 mg/kg; p.o.) and reference compound donepezil (1 mg/kg; p.o.) were administered for 15 consecutive days. Cognitive changes were assessed by transfer latency (TL) using the elevated plus maze (EPM) test. The changes in acetylcholinesterase (AChE) activity were estimated in the septohippocampal system of rat brains. The administration of STZ caused significant changes in cognitive functions (increased TL) as compared to the normal group. BC ameliorated the anxiety-related cognitive behavior and neurotransmitter (elevated AChE) changes provoked by diabetic VaD. Therefore, BC could be a potential therapeutic candidate in the management of VaD.

Ellagic Acid: A Dietary-Derived Phenolic Compound for Drug Discovery in Mild Cognitive Impairment

Ellagic acid (EA), a naturally occurring polyphenolic compound, is detected in free form or linked to polyols or sugars, constituting hydrolyzable tannins or ellagitannins in distinct fruits, nuts, and herbs. Today, a considerable number of botanicals and enriched foods containing EA are commercially available as nutraceuticals and used to prevent mild cognitive impairment (MCI) due to the excellent neuroprotective capacity of EA. Here, this study aims to provide an overview of the physicochemical properties, source, and pharmacokinetics of EA and to emphasize the importance and mechanisms of EA in the prevention and management of MCI. To date, preclinical studies of EA and its derivatives in various cell lines and animal models have advanced the idea of dietary EA as a feasible agent capable of specifically targeting and improving MCI. The molecular mechanisms of EA and its derivatives to prevent or reduce MCI are mainly through reducing neuroinflammation, oxidative stress, neuronal apoptosis, synaptic dysfunction and loss, and defective mitochondrial functions. Nevertheless, well-designed and correctly large randomized controlled trials in the human population need to be performed to reinforce the scientific facticity of the beneficial effects of EA against MCI. Synchronously, the mechanism of EA against MCI is least provided cynosure and expects more attention from the emerging research community.

Assessing the Ecosystem Services Potential of Endemic Floras: A Systematic Review on the Greek Endemics of Peloponnese

As the interest in new, natural, sustainable products arises in many fields, wild plants are reconsidered as providers of traditional or innovative applications. The notion of ecosystem services (ES) provides a frame to evaluate their benefits, but is still scarcely applied to endemic floras. The present study reviews the available literature on the ES provided by the 494 taxa endemic to Greece that are present in Peloponnese. Six main categories are isolated: medical, aromatic, folk medicine, antimicrobial, environmental and craftsmanship interests. The literature documents such ES for 24.7% of the endemic taxa, with Lamiaceae, Asteraceae and Boraginaceae as the families with the highest numbers of documented taxa. Spatial hotspots with a high density in taxa providing ES are mapped, while gaps of knowledge on the ES of endemic taxa are highlighted. For the first time, to our knowledge, taxonomic and phylogenetic bounds between taxa are exploited as a base to explore potential properties for endemic taxa. The basis for the development of predictive tools utilizing literature review datasets is set. Final outcomes also provide robust scientific evidence to support decision and policy making for the sustainable use and management of rural areas. The development of cultivation areas for threatened taxa of interest is suggested as a potent conservation measure, by selecting fields according to habitat suitability models.

In Silico Screening of Natural Compounds for Candidates 5HT6 Receptor Antagonists against Alzheimer's Disease

Alzheimer's disease (AD), a devastating neurodegenerative disease, is the focus of pharmacological research. One of the targets that attract the most attention for the potential therapy of AD is the serotonin 5HT6 receptor, which is the receptor situated exclusively in CNS on glutamatergic and GABAergic neurons. The neurochemical impact of this receptor supports the hypothesis about its role in cognitive, learning, and memory systems, which are of critical importance for AD. Natural products are a promising source of novel bioactive compounds with potential therapeutic potential as a 5HT6 receptor antagonist in the treatment of AD dementia. The ZINC-natural product database was in silico screened in order to find the candidate antagonists of 5-HT6 receptor against AD. A virtual screening protocol that includes both short-and long-range interactions between interacting molecules was employed. First, the EIIP/AQVN filter was applied for in silico screening of the ZINC database followed by 3D QSAR and molecular docking. Ten best candidate compounds were selected from the ZINC Natural Product database as potential 5HT6 Receptor antagonists and were proposed for further evaluation. The best candidate was evaluated by molecular dynamics simulations and free energy calculations.

Targeting transforming growth factor-β signalling for cancer prevention and intervention: Recent advances in developing small molecules of natural origin

BACKGROUND

Cancer is the world's second leading cause of death, but a significant advancement in cancer treatment has been achieved within the last few decades. However, major adverse effects and drug resistance associated with standard chemotherapy have led towards targeted treatment options.

OBJECTIVES

Transforming growth factor-β (TGF-β) signaling plays a key role in cell proliferation, differentiation, morphogenesis, regeneration, and tissue homeostasis. The prime objective of this review is to decipher the role of TGF-β in oncogenesis and to evaluate the potential of various natural and synthetic agents to target this dysregulated pathway to confer cancer preventive and anticancer therapeutic effects.

METHODS

Various authentic and scholarly databases were explored to search and obtain primary literature for this study. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria was followed for the review.

RESULTS

Here we provide a comprehensive and critical review of recent advances on our understanding of the effect of various bioactive natural molecules on the TGF-β signaling pathway to evaluate their full potential for cancer prevention and therapy.

CONCLUSION

Based on emerging evidence as presented in this work, TGF-β-targeting bioactive compounds from natural sources can serve as potential therapeutic agents for prevention and treatment of various human malignancies.

Alvarez KL, Aguilar-Pineda JA, Vera-Lopez KJ, Lino Cardenas CL. In Silico Analysis of Metabolites from Peruvian Native Plants as Potential Therapeutics against Alzheimer's Disease

Background: Despite research on the molecular bases of Alzheimer’s disease (AD), effective therapies against its progression are still needed. Recent studies have shown direct links between AD progression and neurovascular dysfunction, highlighting it as a potential target for new therapeutics development. In this work, we screened and evaluated the inhibitory effect of natural compounds from native Peruvian plants against tau protein, amyloid beta, and angiotensin II type 1 receptor (AT1R) pathologic AD markers. Methods: We applied in silico analysis, such as virtual screening, molecular docking, molecular dynamics simulation (MD), and MM/GBSA estimation, to identify metabolites from Peruvian plants with inhibitory properties, and compared them to nicotinamide, telmisartan, and grapeseed extract drugs in clinical trials. Results: Our results demonstrated the increased bioactivity of three plants’ metabolites against tau protein, amyloid beta, and AT1R. The MD simulations indicated the stability of the AT1R:floribundic acid, amyloid beta:rutin, and tau:brassicasterol systems. A polypharmaceutical potential was observed for rutin due to its high affinity to AT1R, amyloid beta, and tau. The metabolite floribundic acid showed bioactivity against the AT1R and tau, and the metabolite brassicasterol showed bioactivity against the amyloid beta and tau. Conclusions: This study has identified molecules from native Peruvian plants that have the potential to bind three pathologic markers of AD.

Curcuma longa L. Prevents the Loss of β-Tubulin in the Brain and Maintains Healthy Aging in Drosophila melanogaster

Loss of tubulin is associated with neurodegeneration and brain aging. Turmeric (Curcuma longa L.) has frequently been employed as a spice in curry and traditional medications in the Indian subcontinent to attain longevity and better cognitive performance. We aimed to evaluate the unelucidated mechanism of how turmeric protects the brain to be an anti-aging agent. D. melanogaster was cultured on a regular diet and turmeric-supplemented diet. β-tubulin level and physiological traits including survivability, locomotor activity, fertility, tolerance to oxidative stress, and eye health were analyzed. Turmeric showed a hormetic effect, and 0.5% turmeric was the optimal dose in preventing aging. β-tubulin protein level was decreased in the brain of D. melanogaster upon aging, while a 0.5% turmeric-supplemented diet predominantly prevented this aging-induced loss of β-tubulin and degeneration of physiological traits as well as improved β-tubulin synthesis in the brain of D. melanogaster early to mid-age. The higher concentration (≥ 1%) of turmeric-supplemented diet decreased the β-tubulin level and degenerated many of the physiological traits of D. melanogaster. The turmeric concentration-dependent increase and decrease of β-tubulin level were consistent with the increment and decrement data obtained from the evaluated physiological traits. This correlation demonstrated that turmeric targets β-tubulin and has both beneficial and detrimental effects that depend on the concentration of turmeric. The findings of this study concluded that an optimal dosage of turmeric could maintain a healthy neuron and thus healthy aging, by preventing the loss and increasing the level of β-tubulin in the brain.

In silico Study of Acetylcholinesterase and Beta-secretase Inhibitors: Potential Multitarget Anti-Alzheimer's Agents

BACKGROUND

Alzheimer's disease is a progressive neurodegenerative process with multifactorial characteristics. This disease follows the natural aging process, affecting mainly people over 65 years. Pharmacotherapeutic treatment currently combats symptoms related to cognitive function. Several targets have begun to attract the interest of the scientific community to develop new drug candidates which have better pharmacokinetic and lower toxicity parameters.

OBJECTIVE

The present study aims to design new candidates for acetylcholinesterase/β-secretase (AChE/BACE1) multitarget inhibitor drugs.

METHODS

17 natural products were selected from the literature with anticholinesterase activity and 1 synthetic molecule with inhibitory activity for BACE1. Subsequently, the molecular docking study was performed, followed by the derivation of the pharmacophoric pattern and prediction of pharmacokinetic and toxicological properties. Finally, the hybrid prototype was designed.

RESULTS

All selected molecules showed interactions with their respective target enzymes. Derivation of the pharmacophoric pattern from molecules that interacted with the AChE enzyme resulted in 3 pharmacophoric regions: an aromatic ring, an electron-acceptor region and a hydrophobic region. The molecules showed good pharmacokinetic and toxicological results, showing no warnings of mutagenicity and/or carcinogenicity. After the hybridization process, three hybrid molecules were obtained, which showed inhibitory activity for both targets.

CONCLUSION

It is concluded that research in the field of medicinal chemistry is advancing towards the discovery of new drug candidates that bring a better quality of life to patients with AD.

Bisindole compound 4ae ameliorated cognitive impairment in rats with vascular dementia by anti-inflammation effect via microglia cells

Neuroinflammation is considered as an important mechanism of vascular dementia (VaD). Our primary study showed that the bisindole analogue (2-(2-(bis(5-chloro-1H-indol-3-yl)methyl)phenoxy)aniline, compound 4ae) had great anti-inflammation in zebrafish. Rat model of permanent occlusion of the bilateral common carotid arteries (2-vessel occlusion, 2VO) was utilized to evaluate the neuroprotective effect of 4ae. Our results showed that 4ae treatment effectively reduced Iba-1 positive microglia cells in cerebral cortex and hippocampus after cerebral ischemia. Compared with the model group, neuroinflammation characterized by Interleukin (IL)-6 and tumor necrosis factor (TNF)-α, oxidative stress characterized by reactive oxygen species (ROS) and superoxide dismutase (SOD) were both improved significantly after treatment with 4ae. Moreover, 4ae treatment significantly reversed ischemia-induced ACE enhancement, while notably increased the level of ACE2. To further elucidate the role of 4ae on neuroinflammation, we investigated the effects of 4ae on lipopolysaccharide (LPS)-induced inflammation in BV2 microglia cells, a kind of innate immune cells in central nervous system. The results demonstrated that the expressions of CD11b, TNFα and IL-6 and the level of ROS were up-regulated after treatment with LPS. More importantly, 4ae was able to block the activation of BV2 by reducing ROS production and the expression of inflammatory cytokines. In addition, our results suggested that 4ae inhibited the inflammatory response mediated by microglia cells by inhibiting NF-κB. This anti-inflammatory effect on microglia may be a potential mechanism for the neuroprotective effect of 4ae in VaD.

Ayurveda Rasayana as antivirals and immunomodulators: potential applications in COVID-19

Coronavirus disease (COVID-19) has been declared as a pandemic by the World Health Organization with rapid spread across 216 countries. COVID-19 pandemic has left its imprints on various health systems globally and caused immense social and economic disruptions. The scientific community across the globe is in a quest for digging the effective treatment for COVID-19 and exploring potential leads from traditional systems of healthcare across the world too. Ayurveda (Indian traditional system of medicine) has a comprehensive aspect of immunity through Rasayana which is a rejuvenation therapy. Here we attempt to generate the potential leads based on the classical text from Ayurveda in general and Rasayana in particular to develop effective antiviral and/or immunomodulator for potential or adjunct therapy in SARS-CoV-2. The Rasayana acts not only by resisting body to restrain or withstand the strength, severity or progression of a disease but also by promoting power of the body to prevent the manifestation of a disease. These Rasayana herbs are common in practice as immunomodulator, antiviral and protectives. The studies on Rasayana can provide an insight into the future course of research for the plausible development of effective management of COVID-19 by the utilization and development of various traditional systems of healthcare. Keeping in view the current pandemic situation, there is an urgent need of developing potential medicines. This study proposes certain prominent medicinal plants which may be further studied for drug development process and also in clinical setup under repurposing of these herbs.

Medicinal herbs and nutritional supplements for dementia therapy: potential therapeutic targets and clinical evidence

Spices and herbs have been used for medicinal purposes for centuries. Also, in the last decades, the use of different nutritional supplements has been implemented to treat all kinds of diseases, including those that present an alteration in cognitive functioning. Dementia is a clinical syndrome in which a person's mental and cognitive capacities gradually decline. As the disease progresses, the person's autonomy diminishes. As there is not an effective treatment to prevent progressive deterioration in many of these pathologies, nutritional interventions have been, and still are, one of the most widely explored therapeutic possibilities. In this review, we have discussed a great number of potentially interesting plants, nutritional derivatives and probiotics for the treatment of dementia around the world. Their action mechanisms generally involve neuroprotective effects via anti-inflammatory, antioxidant, anti-apoptotic, b-amyloid and tau anti-aggregate actions; brain blood flow improvement, and effects on synaptic cholinergic and dopaminergic neurotransmission, which may optimize cognitive performance in patients with cognitive impairment. As for their efficacy in patients with cognitive impairment and/or dementias, evidence is still scarce and/or their outcomes are controversial. We consider that many of these substances have promising therapeutic properties. Therefore, the scientific community has to continue with a more complete research focused on both identifying possible action mechanisms and carrying out clinical trials, preferably randomized double-blind ones, with a greater number of patients, a long-term follow-up, dose standardization and the use of current diagnosis criteria.

A Novel Cardenolide Glycoside Isolated from Xysmalobium undulatum Reduces Levels of the Alzheimer's Disease-Associated β-Amyloid Peptides Aβ42 In Vitro

Elevated levels of the amylo β-proteins (Aβ), particularly Aβ42, are associated with a high risk of Alzheimer’s disease (AD). The Aβ proteins are produced from cellular processing of the amyloid precursor proteins (APPs). To identify natural products that block the formation of Aβ-proteins from APPs, we previously screened a library of plant extracts and identified Xysmalobium undulaum (Apocynaceae) as a potential plant for further research. Here, we provide a report on the isolation and identification of the active principles from the plant species using a bioassay-guided fractionation. Fractions and resulting pure compounds from the purification process of the extract of X. undulatum were screened in vitro against APPs transfected HeLa cell lines. Three compounds, acetylated glycosydated crotoxogenin (1), xysmalogenin-3, β-d-glucopyranoside (2), and crotoxigenin 3-O-glucopyranoside (3), were subsequently isolated and their structures elucidated using NMR and mass spectrometry. Compound 1, a novel cardenolide, and 2 significantly decreased the Aβ42 levels in a dose-dependent manner while compound 3 was inactive. In silico investigations identified the AD’s β-secretase enzyme, BACE1, as a potential target for these compounds with the glycoside moiety being of significance in binding to the enzyme active site. Our study provides the first report of a novel cardenolide and the potential of cardenolides as chemical scaffolds for developing AD treatment drugs.

Herbal Medicine for Behavioral and Psychological Symptoms of Dementia: A Systematic Review and Meta-Analysis

Background: Dementia is a global health concern, causing serious health and socioeconomic burdens with population aging. The associated symptoms of dementia, called behavioral and psychological symptoms of dementia (BPSD), are factors contributing to the socioeconomic burden of dementia. Recently, herbal medicine (HM) has attracted attention as a potential complementary therapy for BPSD. Therefore, this systematic review was aimed at analyzing the effectiveness (or efficacy), safety, and research status of HM in BPSD management through a comprehensive review.

Methods: Thirteen electronic databases were searched comprehensively. Related clinical studies published until December 28, 2020, were collected. The methodological quality was evaluated using tools such as the Cochrane Collaboration’s risk of bias tool according to the study design. The effectiveness (or efficacy) was analyzed for randomized controlled trials (RCTs) only, and when sufficient homogeneity was assured, effect estimates were presented as mean difference (MD) and risk ratio (RR), with 95% confidence interval (CIs), through a meta-analysis.

Results: A total of 52 clinical studies, including 36 RCTs, were included in this review. As an adjunctive therapy, HM showed statistically significant benefits in BPSD severity assessed by the Behavior Pathology in Alzheimer’s Disease Rating Scale (combined with psychotropic drugs: MD = −3.48, 95% CI: −3.96 to −2.99; with anti-dementia drugs: MD = −2.81, 95% CI: −3.17 to −2.45) and Neuropsychiatric Inventory (with anti-dementia drugs: MD = −3.23, 95% CI: −4.06 to −2.40). Adverse events were significantly less frequent in the HM group (RR = 0.50; 95% CI: 0.28 to 0.88). However, the methodological quality of the RCTs included in this systematic review was not optimal overall.

Conclusion: According to the findings of this review, HM may be associated with additional benefits in BPSD treatment, particularly when used as an adjunct to conventional medications, including psychotropic and anti-dementia drugs. However, considering the methodological quality of the included RCTs, this clinical evidence is not robust. Nevertheless, dementia is a global health concern, and considering the limitations of conventional psychotropic drugs for BPSD, a major cause of the disease burden, HM appears to be a promising complementary therapy that warrants further research.

The neuroprotective attribution of Ocimum basilicum: a review on the prevention and management of neurodegenerative disorders

Background

Bioactive principles from various natural resources including medicinal herbs have always played a crucial role in healthcare settings and increasingly became key players in drug discovery and development for many biopharmaceutical applications. Additionally, natural products (NPs) have immense arrangement of distinctive chemical structures with diverse functional groups that motivated numerous investigators including synthetic chemists to discover new therapeutic entities. Numerous pre-clinical investigations involving the animal models have evident the usefulness of these NPs against various human diseases including neurodegenerative disorders (NDs).

Main text

Ocimum basilicum Linn (O. basilicum L.), also known as sweet basil, is well practiced in traditional healthcare systems and has been used to treat various human illnesses, which include malaria, skin disease, diarrhea, bronchitis, dysentery, arthritis, eye diseases, and insect bites and emphasize the significance of the ethno-botanical approach as a potential source of novel drug leads With the growing interest in advanced techniques, herbal medicine and medicinal plants explorations are still considered to be a novel resource for new pharmacotherapeutic discovery and development. O. basilicum L and its bioactive principles including apigenin, eugenol, myretenal, β-sitosterol, luteolin, rosmarinic acid, carnosic acid, essential oil (EO)-rich phenolic compounds, and others like anthocyanins and flavones could be of therapeutic values in NDs by exhibiting their neuro-protective efficacy on various signaling pathways. The present comprehensive review collected various related information using the following searching engines such as PubMed, Science Direct, Google Scholar, etc. and focused mainly the English written documents. The search period comprised of last two decades until present.

Conclusion

Although these efficacious plant genera of prime importance and has potential medical and socioeconomic importance, yet the pivotal evidence for its neuroprotective potential in novel clinical trials remains lacking. However, with the available wealth of obtainable literature on this medicinal plant, which supports this review and concludes that O. basilicum L may function as a promising therapeutics for the treatment of NDs.

Natural Products for Neurodegeneration: Regulating Neurotrophic Signals

Neurodegenerative disorders (NDs) are heterogeneous groups of ailments typically characterized by progressive damage of the nervous system. Several drugs are used to treat NDs but they have only symptomatic benefits with various side effects. Numerous researches have been performed to prove the advantages of phytochemicals for the treatment of NDs. Furthermore, phytochemicals such as polyphenols might play a pivotal role in rescue from neurodegeneration due to their various effects as anti-inflammatory, antioxidative, and antiamyloidogenic agents by controlling apoptotic factors, neurotrophic factors (NTFs), free radical scavenging system, and mitochondrial stress. On the other hand, neurotrophins (NTs) including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT4/5, and NT3 might have a crucial neuroprotective role, and their diminution triggers the development of the NDs. Polyphenols can interfere directly with intracellular signaling molecules to alter brain activity. Several natural products also improve the biosynthesis of endogenous genes encoding antiapoptotic Bcl-2 as well as NTFs such as glial cell and brain-derived NTFs. Various epidemiological studies have demonstrated that the initiation of these genes could play an essential role in the neuroprotective function of dietary compounds. Hence, targeting NTs might represent a promising approach for the management of NDs. In this review, we focus on the natural product-mediated neurotrophic signal-modulating cascades, which are involved in the neuroprotective effects.

In vivo anti-inflammatory, anti-nociceptive, and in vitro antioxidant efficacy, and acute oral toxicity effects of the aqueous and methanolic stem bark extracts of Lonchocarpus eriocalyx (Harms.)

Oxidative stress causes and drives many agonising inflammatory conditions, which cause disability, financial burden, and emotional stress. The current anti-inflammatory, analgesic, and antioxidant agents are associated with adverse effects, inaccessibility, high costs, and low efficacies, thereby warranting the need for alternatives, especially from natural sources. Lonchocarpus eriocalyx plant is traditionally used in Kenyan communities to treat various inflammatory and oxidative stress-associated diseases; however, its pharmacologic efficacy and safety have not been empirically validated, hence this study. The in vivo antiinflamatory and antinociceptive efficacy of the aqueous and methanolic stem bark extracts of L. eriocalyx were determined using the xylene-induced ear oedema, and the acetic acid-induced writhing techniques, respectively, in experimental mice. Also, in vitro antioxidant activities of the studied plant extracts were investigated using the Thiobarbituric acid test for lipid peroxidation, 1, 1-diphenyl -2-picrylhydrazyl (DPPH), and Ferric reducing antioxidant power standard assay methods. Moreover, the studied extracts' acute oral toxicity effects were investigated according to the Organisation for Economic Corporation and Development (OECD) guidelines. The studied plant extracts showed significant dose-dependent inhibitions of oedema and writhing, depicting their anti-inflammatory and antinociceptive efficacy. Besides, the extracts revealed significant inhibitions of in vitro lipid peroxidation in varying degrees. Notably, the extracts demonstrated very strong DPPH radical scavenging and ferric-reducing antioxidant efficacies. Furthermore, the two studied plant extracts did not elicit acute oral toxicity, with LD50 values of >2000 mg/kg BW, hence were considered safe. The anti-inflammatory, antinociceptive, and in vitro antioxidant efficacies of these extracts were attributed to antioxidant phytocompounds with diverse pharmacologic effects, especially through the amelioration of oxidative stress. Further studies on the anti-inflammatory, antinociceptive and antioxidant mechanism(s) and isolation and characterisation of responsible compounds are encouraged to spur the development of affordable, accessible, safe, and efficacious drugs.

Analysing Curcuma caesia fractions and essential oil for neuroprotective potential against anxiety, depression, and amnesia

Scientific pieces of evidence support the pharmacological activity of Curcuma caesia for its antidepressant, analgesic, anticonvulsant and antioxidant effect. Here, we evaluate the bioactivity of essential oil and the various polarity-based solvent partitioned fractions obtained from Curcuma caesia for anti-amnesia, anxiolytic and antidepressant activities using Elevated plus maze and Morris water maze models. The cold maceration technique using methanol was adopted for extraction from dried powdered rhizomes and essential oil was extracted by hydrodistillation method. Partitioning of the methanolic extract based on solvent polarity by hexane, ethyl acetate, and methanol was continued, followed by column chromatography of the ethyl acetate fraction. Suspensions were prepared for fractions (dissolved in distilled water) and essential oil (dissolved in tween 20) at 200 mg/kg and 400 mg/kg after acute toxicity study and were orally administered to Wistar albino female rats after the orientation of hypoxia by sodium nitrite (50 mg/kg) and amnesia by scopolamine (1 mg/kg). Behavioural observations, biochemical and histopathological examinations were carried out for all the treated groups. Diazepam (12 mg/kg) and galantamine (3 mg/kg) were used as standard drugs for this study against hypoxia and amnesia. Data acquired from behavioural, biochemical (acetylcholinesterase, myeloperoxidase, superoxide dismutase, reduced glutathione, catalase) and histopathological studies have illustrated that fraction II acquires highly significant memory-enhancing, anxiolytic and antidepressant effects. Rest fractions (I and III) and essential oil showed moderate efficacy. In prospects, identification of active molecules from the most active fraction (fraction II) and further studies on a molecular basis would substantiate its specific mechanism of neuroprotective action.

Curcuma Longa, the "Golden Spice" to Counteract Neuroinflammaging and Cognitive Decline-What Have We Learned and What Needs to Be Done

Due to the global increase in lifespan, the proportion of people showing cognitive impairment is expected to grow exponentially. As target-specific drugs capable of tackling dementia are lagging behind, the focus of preclinical and clinical research has recently shifted towards natural products. Curcumin, one of the best investigated botanical constituents in the biomedical literature, has been receiving increased interest due to its unique molecular structure, which targets inflammatory and antioxidant pathways. These pathways have been shown to be critical for neurodegenerative disorders such as Alzheimer's disease and more in general for cognitive decline. Despite the substantial preclinical literature on the potential biomedical effects of curcumin, its relatively low bioavailability, poor water solubility and rapid metabolism/excretion have hampered clinical trials, resulting in mixed and inconclusive findings. In this review, we highlight current knowledge on the potential effects of this natural compound on cognition. Furthermore, we focus on new strategies to overcome current limitations in its use and improve its efficacy, with attention also on gender-driven differences.

Targeting the crosstalk between canonical Wnt/β-catenin and inflammatory signaling cascades: A novel strategy for cancer prevention and therapy

Emerging scientific evidence indicates that inflammation is a critical component of tumor promotion and progression. Most cancers originate from sites of chronic irritation, infections and inflammation, underscoring that the tumor microenvironment is largely orchestrated by inflammatory cells and pro-inflammatory molecules. These inflammatory components are intimately involved in neoplastic processes which foster proliferation, survival, invasion, and migration, making inflammation the primary target for cancer prevention and treatment. The influence of inflammation and the immune system on the progression and development of cancer has recently gained immense interest. The Wnt/β-catenin signaling pathway, an evolutionarily conserved signaling strategy, has a critical role in regulating tissue development. It has been implicated as a major player in cancer development and progression with its regulatory role on inflammatory cascades. Many naturally-occurring and small synthetic molecules endowed with inherent anti-inflammatory properties inhibit this aberrant signaling pathway, making them a promising class of compounds in the fight against inflammatory cancers. This article analyzes available scientific evidence and suggests a crosslink between Wnt/β-catenin signaling and inflammatory pathways in inflammatory cancers, especially breast, gastrointestinal, endometrial, and ovarian cancer. We also highlight emerging experimental findings that numerous anti-inflammatory synthetic and natural compounds target the crosslink between Wnt/β-catenin pathway and inflammatory cascades to achieve cancer prevention and intervention. Current challenges, limitations, and future directions of research are also discussed.

Bioactive Compounds and Traditional Herbal Medicine: Promising Approaches for the Treatment of Dementia

Dementia is a term that encompasses a group of clinical symptoms affecting memory, thinking and social abilities, characterized by progressive impairment of memory performance and cognitive functions. There are several factors involved in the pathogenesis and progression of dementia, such as old age, brain ischemia, toxin exposure, and oxidative stress. There are extensive similarities between dementia and Alzheimer's disease (AD) either in clinical manifestations or experimental animal models. AD is the most dominant form of dementia, characterized by the accumulation of beta-amyloid protein and cholinergic neurotransmission deficits in the brain. Currently available medications for the treatment of dementia, such as choline esterase inhibitors, N-methyl-D-aspartate (NMDA) antagonists (memantine), have short-term efficacy and only relieve symptoms rather than targeting the main underlying pathogenesis. Several animal studies and clinical trials are being conducted to provide a rational approach to these medicinal plants in the prevention or treatment of memory deficits. This review highlights the potential effects of medicinal plants and their derived lead molecules, and explains the related mechanisms and effects reviewed from published literature as major thrust aspects and hopeful strategies in the prevention or treatment of dementia.

Boldine Attenuates Synaptic Failure and Mitochondrial Deregulation in Cellular Models of Alzheimer's Disease

Alzheimer’s disease (AD) is the most common cause of senile dementia worldwide, characterized by both cognitive and behavioral deficits. Amyloid beta peptide (Aβ) oligomers (AβO) have been found to be responsible for several pathological mechanisms during the development of AD, including altered cellular homeostasis and synaptic function, inevitably leading to cell death. Such AβO deleterious effects provide a way for identifying new molecules with potential anti-AD properties. Available treatments minimally improve AD symptoms and do not extensively target intracellular pathways affected by AβO. Naturally-derived compounds have been proposed as potential modifiers of Aβ-induced neurodysfunction and cytotoxicity based on their availability and chemical diversity. Thus, the aim of this study was to evaluate boldine, an alkaloid derived from the bark and leaves of the Chilean tree Peumus boldus, and its capacity to block some dysfunctional processes caused by AβO. We examined the protective effect of boldine (1–10 μM) in primary hippocampal neurons and HT22 hippocampal-derived cell line treated with AβO (24–48 h). We found that boldine interacts with Aβ in silico affecting its aggregation and protecting hippocampal neurons from synaptic failure induced by AβO. Boldine also normalized changes in intracellular Ca²⁺ levels associated to mitochondria or endoplasmic reticulum in HT22 cells treated with AβO. In addition, boldine completely rescued the decrease in mitochondrial membrane potential (ΔΨm) and the increase in mitochondrial reactive oxygen species, and attenuated AβO-induced decrease in mitochondrial respiration in HT22 hippocampal cells. We conclude that boldine provides neuroprotection in AD models by both direct interactions with Aβ and by preventing oxidative stress and mitochondrial dysfunction. Additional studies are required to evaluate the effect of boldine on cognitive and behavioral deficits induced by Aβ in vivo.

Neuropharmacological studies of ethanolic extract of Vaccinium corymbosum on Alzheimer’s type dementia and catatonia in Swiss albino mice

Introduction: Neuroactive herbal drugs enriched with antioxidants are valuable in treating neurocognitive dysfunction and Vaccinium corymbosum, enriched with antioxidant phytochemicals, is used for treating memory disorders. Hence, the present study evaluated the neuroprotective effects of ethanolic extract of Vaccinium corymbosum (EEVC) on aluminium chloride(AlCl3)-induced Alzheimer’s type of dementia and haloperidol-induced catalepsy-associated behavioural changes. Methods:In vitro antioxidant potential was evaluated using 1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). The total phenolic content (TPC) was quantified. For in vivo studies, AlCl3 (100 mg/kg) was orally administered for 42 days, whereas the EEVC was administered on the 21st day until the 42nd day in two doses (200 mg/kg and 400 mg/kg). In the haloperidol-induced group, EEVC was treated for 21 days, and haloperidol (1 mg/kg) was administered to induce behavioural changes. Open-field, Y-Maze and traction tests were performed, and the mice brain acetylcholinesterase (AChE) enzyme was determined. Results: IC50 values in DPPH and ABTS assays were 85.5 μg/mL and 80 μg/mL, respectively and the total phenolic content of EEVC was found to be 0.166 mg. In a behavioral study, animals treated with 200 mg/kg and 400 mg/kg of EEVC exhibited a neuroprotective impact on AlCl3-induced neurodegeneration and haloperidol-induced behavioral changes with significant inhibition (P < 0.05 and P < 0.01, respectively) in acetylcholinesterase enzyme. Conclusion: The neuroprotection by EEVC postulated that it is a promising therapeutic agent for treating behavioral and cognitive dysfunctions. Further investigations on pro-inflammatory cytokine and neuroendocrine regulation in transgenic Alzheimer’s disease (AD)models complement the therapeutic value of V. corymbosum.

β-Sitosterol treatment attenuates cognitive deficits and prevents amyloid plaque deposition in amyloid protein precursor/presenilin 1 mice

Alzheimer's disease (AD) is the most common neurodegenerative disorder causing dementia worldwide, and is mainly characterized by aggregated β-amyloid (Aβ). Increasing evidence has shown that plant extracts have the potential to delay AD development. The plant sterol β-Sitosterol has a potential role in inhibiting the production of platelet Aβ, suggesting that it may be useful for AD prevention. In the present study, we aimed to investigate the effect and mechanism of β-Sitosterol on deficits in learning and memory in amyloid protein precursor/presenilin 1 (APP/PS1) double transgenic mice. APP/PS1 mice were treated with β-Sitosterol for four weeks, from the age of seven months. Brain Aβ metabolism was evaluated using ELISA and Western blotting. We found that β-Sitosterol treatment can improve spatial learning and recognition memory ability, and reduce plaque load in APP/PS1 mice. β-Sitosterol treatment helped reverse dendritic spine loss in APP/PS1 mice and reversed the decreased hippocampal neuron miniature excitatory postsynaptic current frequency. Our research helps to explain and support the neuroprotective effect of β-Sitosterol, which may offer a novel pharmaceutical agent for the treatment of AD. Taken together, these findings suggest that β-Sitosterol ameliorates memory and learning impairment in APP/PS1 mice and possibly decreases Aβ deposition.

Natural products improve healthspan in aged mice and rats: A systematic review and meta-analysis

Over the last decades a decrease in mortality has paved the way for late onset pathologies such as cardiovascular, metabolic or neurodegenerative diseases. This evidence has led many researchers to shift their focus from researching ways to extend lifespan to finding ways to increase the number of years spent in good health; "healthspan" is indeed the emerging concept of such quest for ageing without chronic or disabling diseases and dysfunctions. Regular consumption of natural products might improve healthspan, although the mechanisms of action are still poorly understood. Since preclinical studies aimed to assess the efficacy and safety of these compounds are growing, we performed a systematic review and meta-analysis on the effects of natural products on healthspan in mouse and rat models of physiological ageing. Results indicate that natural compounds show robust effects improving stress resistance and cognitive abilities. These promising data call for further studies investigating the underlying mechanisms in more depth.

Molecular mechanism of zinc neurotoxicity in Alzheimer's disease

Zinc (Zn) is an essential trace element for most organisms, including human beings. It plays a crucial role in several physiological processes such as catalytic reaction of enzymes, cellular growth, differentiation and metabolism, intracellular signaling, and modulation of nucleic acid structure. Zn containing above 50 metalloenzymes is responsible for proteins, receptors, and hormones synthesis and has a critical role in neurodevelopment. Zn also regulates excitatory and inhibitory neurotransmitters such as glutamate and GABA and is found in high concentration in the synaptic terminals of hippocampal mossy fibers that maintains cognitive function. It regulates LTP and LTD by regulation of AMPA and NMDA receptors. But an excess or deficiency of Zn becomes neurotoxic or cause impairment in growth or sexual maturation. There is mounting evidence that supports this idea of Zn becoming neurotoxic and being involved in the pathogenesis of AD. Zn dyshomeostasis in AD is an area that needs attention as moderate concentration of Zn is involved in the memory regulation via regulation of amyloid plaque. Dyshomeostasis of Zn is involved in the pathogenesis of diseases like AD, ALS, depression, PD, and schizophrenia.

Neuroprotective potential of the oxindole alkaloids isomitraphylline and mitraphylline in human neuroblastoma SH-SY5Y cells

The purified oxindole alkaloids, isomitraphylline and mitraphylline from Uncaria perrottetii, revealed their ability to break amyloid aggregates in vitro suggesting their therapeutic potentials in Alzheimer's disease (AD). Thioflavin-T assay for assessing amyloid-beta (Aβ) aggregation of these alkaloids exhibited inhibitions at 60.321% ± 2.61 (50 μM) for isomitraphylline and 43.17% ± 3.48 (50 μM) for mitraphylline. Neuroprotective effects were elaborated against Aβ-induced SH-SY5Y cells at 20 μM and 10 μM for isomitraphylline, and 20 μM for mitraphylline. In addition, both alkaloids attenuated and protected the H₂O₂-induced SH-SY5Y cell cytotoxicity at 20 μM. The intracellular ROS levels of SH-SY5Y cells from H₂O₂-induced oxidative stress were reduced at 20 μM and 10 μM, and the mitochondrial membrane potentials of Aβ-induced SH-SY5Y cells were protected at 20 μM. The overall results suggested the potentials of both alkaloids to target certain pathological biomarkers of AD and could be further investigated as therapeutic or preventive drug leads against AD.