Meta-analysis of Ginkgo biloba Preparation for the Treatment of Alzheimer's Disease

[Clinical guidelines «Cognitive disorders in the elderly and senile persons»]

Clinical guidelines «Cognitive disorders in the elderly and senile persons».

Ginkgo biloba and Its Chemical Components in the Management of Alzheimer's Disease

The pathogenesis of Alzheimer's disease (AD), a degenerative disease of the central nervous system, remains unclear. The main manifestations of AD include cognitive and behavioral disorders, neuropsychiatric symptoms, neuroinflammation, amyloid plaques, and neurofibrillary tangles. However, current drugs for AD once the dementia stage has been reached only treat symptoms and do not delay progression, and the research and development of targeted drugs for AD have reached a bottleneck. Thus, other treatment options are needed. Bioactive ingredients derived from plants are promising therapeutic agents. Specifically, Ginkgo biloba (Gb) extracts exert anti-oxidant, anticancer, neuroplastic, neurotransmitter-modulating, blood fluidity, and anti-inflammatory effects, offering alternative options in the treatment of cardiovascular, metabolic, and neurodegenerative diseases. The main chemical components of Gb include flavonoids, terpene lactones, proanthocyanidins, organic acids, polysaccharides, and amino acids. Gb and its extracts have shown remarkable therapeutic effects on various neurodegenerative diseases, including AD, with few adverse reactions. Thus, high-quality Gb extracts are a well-established treatment option for AD. In this review, we summarize the insights derived from traditional Chinese medicine, experimental models, and emerging clinical trials on the role of Gb and its chemical components in the treatment of the main clinical manifestations of AD.

State-of-the-Art Review on Botanical Hybrid Preparations in Phytomedicine and Phytotherapy Research: Background and Perspectives

BACKGROUND

Despite some evidence supporting the synergy concept, the commonly known assumption that combinations of several herbs in one formulation can have better efficacy due to additive or synergistic effects has yet to be unambiguously and explicitly studied.

STUDY AIM

The study aimed to reveal the molecular interactions in situ of host cells in response to botanical hybrid preparations (BHP) intervention and justify the benefits of implementing BHP in clinical practice.

RESULTS

This prospective literature review provides the results of recent clinical and network pharmacology studies of BHP of Rhodiola rosea L. (Arctic root) with other plants, including Withania somnifera (L.) Dunal (ashwagandha), (Camellia sinensis (L.) Kuntze (green tea), Eleutherococcus senticosus (Rupr. and Maxim.) Maxim. (eleuthero), Schisandra chinensis (Turcz.) Baill. (schisandra), Leuzea carthamoides (Willd.) DC., caffeine, Cordyceps militaris L., Ginkgo biloba L.(ginkgo), Actaea racemosa L. (black cohosh), Crocus sativus L. (saffron), and L-carnosine.

CONCLUSIONS

The most important finding from network pharmacology studies of BHP was the evidence supporting the synergistic interaction of BHP ingredients, revealing unexpected new pharmacological activities unique and specific to the new BHP. Some studies show the superior efficacy of BHP compared to mono-drugs. At the same time, some a priori-designed combinations can fail, presumably due to antagonistic interactions and crosstalk between molecular targets within the molecular networks involved in the cellular and overall response of organisms to the intervention. Network pharmacology studies help predict the results of studies aimed at discovering new indications and unpredicted adverse events.

Pharmacodynamic and Clinical Effects of Ginkgo Biloba Extract EGb 761 and Its Phytochemical Components in Alzheimer's Disease

Extracts made from plants are complex mixtures of substances with varying compositions depending on the plant material and method of manufacture. This complexity makes it difficult for scientists and clinicians to interpret findings from pharmacological and clinical research. We performed a narrative review summarizing information on ginkgo biloba leaf extract, its composition, pharmacological data and clinical evidence supporting its administration for the treatment of Alzheimer's disease (AD). Medicinal products containing ginkgo biloba leaf extract which are manufactured in compliance with the requirements of the European Pharmacopoeia are approved as medicinal products for the treatment of dementia and related conditions by drug regulatory agencies in Europe, Asia and South America. As multicomponent mixtures, they may affect various targets in the pathogenesis of AD, the most common form of dementia. Pharmacodynamic studies demonstrate the effects of EGb 761 and individual constituents on various pathophysiological features of experimentally induced cognitive impairment and neurodegeneration that could contribute to its clinical efficacy. The safety and efficacy in the treatment of AD and cognitive decline has been studied in randomized, placebo-controlled clinical trials. Most of the studies that investigate the effects of ginkgo biloba extract (GbE) used the special extract EGb 761, which makes it the best-researched plant preparation worldwide. It is therefore the only herbal alternative to standard-of-care anti-dementia drugs. However, the mechanism of action has not been fully elucidated yet, and the clinical studies in AD show heterogeneity.

Overview and Recent Progress on the Biosynthesis and Regulation of Flavonoids in Ginkgo biloba L

Flavonoids and their derivatives play important roles in plants, such as exerting protective activity against biotic and abiotic stresses, functioning in visual signaling to attract pollinators, and regulating phytohormone activity. They are also important secondary metabolites that are beneficial to humans. Ginkgo biloba L. is a well-known relict plant considered to be a "living fossil". Flavonoids present in ginkgo leaves have antioxidant and anti-aging capacities and show good therapeutic effects on a variety of neurological diseases. To date, studies on flavonoids have mainly focused on their extraction, pharmacological effects, and component analysis and on the expression levels of the key genes involved. However, a systematic review summarizing the biosynthesis and regulatory mechanisms of ginkgo flavonoids is still lacking. Thus, this review was conducted to comprehensively introduce the biological characteristics, value, and utilization status of ginkgo; summarize the effects, biosynthetic pathways, and transcriptional regulation of flavonoids; and finally, discuss the factors (ecological factors, hormones, etc.) that regulate the biosynthesis of flavonoids in ginkgo. This review will provide a reference basis for future research on the biosynthesis and efficient utilization of flavonoids in ginkgo.

From Answers to Insights: Unveiling the Strengths and Limitations of ChatGPT and Biomedical Knowledge Graphs

Purpose

Large Language Models (LLMs) have shown exceptional performance in various natural language processing tasks, benefiting from their language generation capabilities and ability to acquire knowledge from unstructured text. However, in the biomedical domain, LLMs face limitations that lead to inaccurate and inconsistent answers. Knowledge Graphs (KGs) have emerged as valuable resources for organizing structured information. Biomedical Knowledge Graphs (BKGs) have gained significant attention for managing diverse and large-scale biomedical knowledge. The objective of this study is to assess and compare the capabilities of ChatGPT and existing BKGs in question-answering, biomedical knowledge discovery, and reasoning tasks within the biomedical domain.

Methods

We conducted a series of experiments to assess the performance of ChatGPT and the BKGs in various aspects of querying existing biomedical knowledge, knowledge discovery, and knowledge reasoning. Firstly, we tasked ChatGPT with answering questions sourced from the "Alternative Medicine" sub-category of Yahoo! Answers and recorded the responses. Additionally, we queried BKG to retrieve the relevant knowledge records corresponding to the questions and assessed them manually. In another experiment, we formulated a prediction scenario to assess ChatGPT's ability to suggest potential drug/dietary supplement repurposing candidates. Simultaneously, we utilized BKG to perform link prediction for the same task. The outcomes of ChatGPT and BKG were compared and analyzed. Furthermore, we evaluated ChatGPT and BKG's capabilities in establishing associations between pairs of proposed entities. This evaluation aimed to assess their reasoning abilities and the extent to which they can infer connections within the knowledge domain.

Results

The results indicate that ChatGPT with GPT-4.0 outperforms both GPT-3.5 and BKGs in providing existing information. However, BKGs demonstrate higher reliability in terms of information accuracy. ChatGPT exhibits limitations in performing novel discoveries and reasoning, particularly in establishing structured links between entities compared to BKGs.

Conclusions

To address the limitations observed, future research should focus on integrating LLMs and BKGs to leverage the strengths of both approaches. Such integration would optimize task performance and mitigate potential risks, leading to advancements in knowledge within the biomedical field and contributing to the overall well-being of individuals.

From Answers to Insights: Unveiling the Strengths and Limitations of ChatGPT and Biomedical Knowledge Graphs

Large Language Models (LLMs) have demonstrated exceptional performance in various natural language processing tasks, utilizing their language generation capabilities and knowledge acquisition potential from unstructured text. However, when applied to the biomedical domain, LLMs encounter limitations, resulting in erroneous and inconsistent answers. Knowledge Graphs (KGs) have emerged as valuable resources for structured information representation and organization. Specifically, Biomedical Knowledge Graphs (BKGs) have attracted significant interest in managing large-scale and heterogeneous biomedical knowledge. This study evaluates the capabilities of ChatGPT and existing BKGs in question answering, knowledge discovery, and reasoning. Results indicate that while ChatGPT with GPT-4.0 surpasses both GPT-3.5 and BKGs in providing existing information, BKGs demonstrate superior information reliability. Additionally, ChatGPT exhibits limitations in performing novel discoveries and reasoning, particularly in establishing structured links between entities compared to BKGs. To overcome these limitations, future research should focus on integrating LLMs and BKGs to leverage their respective strengths. Such an integrated approach would optimize task performance and mitigate potential risks, thereby advancing knowledge in the biomedical field and contributing to overall well-being.

Efficacy and safety of herbal medicine on dementia and cognitive function: An umbrella review of systematic reviews and meta-analysis

This study aims to summarize the effects of herbs on dementia and assess the strength of evidence. Six international and local databases were searched from inception to October 2021 for systematic reviews and meta-analyses of clinical trials investigated the effects of herbal medicine on dementia or cognitive function. Two researchers independently extracted data, assessed the methodological quality, and rated the credibility of evidence according to established criteria. Thirty-seven articles evaluating 13 herbal medicines were included. Of these, 65% were rated critically low using AMSTAR2. Of 90 unique outcomes, 41 (45.6%) were statistically significant based on random effects model (p ≤ .05). Only 3 herbs were supported by suggestive evidence whereas the others were supported by weak evidence. The suggestive evidence supported benefits of Chinese herbal medicine (CHM) plus pharmacotherapy (WMD:1.84; 95% CI: 1.34, 2.35) and Vinpocetine (WMD: -0.94; 95%CI: -1.50, -0.38) on improving cognitive function assessing by Montreal Cognitive Assessment and Syndrom-Kurz-Test, respectively. Moreover, suggestive evidence supported benefit of Huperzia serrata on improving Activities of Daily Living (WMD:-7.18; 95%CI: -9.12, -5.23). No SAE was reported. In conclusion, several herbs were used for improving dementia and cognitive function but recent evidence were limited by the small sample size and poor methodological quality. Therefore, further large and well-designed studies are needed to support the evidence.

Mapping new pharmacological interventions for cognitive function in Alzheimer's disease: a systematic review of randomized clinical trials

Background and Objective: Alzheimer's disease (AD) is a progressive neurodegenerative disorder, that is, characterized by cognitive decline. To date, there are no effective treatments for AD. Therefore, the objective of this study was to map new perspectives on the effects of pharmacological treatment on cognitive function and the overall psychological state in patients with AD. Methods: Two independent researchers searched for randomized clinical trials (RCTs) exploring new pharmacological approaches related to cognition in Alzheimer's disease in adults from 2018 to 2023 in PubMed, Web of Science, Scopus, and Cochrane Library databases. A total of 17 RCTs were included in this review. Results: The results show that in recent years, new drugs have been tested in patients with Alzheimer's disease, including masitinib, methylphenidate, levetiracetam, Jiannao Yizhi, and Huannao Yicong formulas. Most studies have been conducted in populations with mild to moderate Alzheimer's disease. Conclusion: Although some of the drugs found suggested improvement in cognitive function, the scarcity of available studies highlights the need for further research in this area. Systematic review registration: [www.crd.york.ac.uk/prospero], identifier [CRD42023409986].

The Role of Phytochemicals and Gut Microbiome in Atherosclerosis in Preclinical Mouse Models

Gut microbiome alterations have recently been linked to many chronic conditions including cardiovascular disease (CVD). There is an interplay between diet and the resident gut microbiome, where the food eaten affects populations of certain microbes. This is important, as different microbes are associated with various pathologies, as they can produce compounds that are disease-promoting or disease-protecting. The Western diet negatively affects the host gut microbiome, ultimately resulting in heightened arterial inflammation and cell phenotype changes as well as plaque accumulation in the arteries. Nutritional interventions including whole foods rich in fiber and phytochemicals as well as isolated compounds including polyphenols and traditional medicinal plants show promise in positively influencing the host gut microbiome to alleviate atherosclerosis. This review investigates the efficacy of a vast array of foods and phytochemicals on host gut microbes and atherosclerotic burden in mice. Reduction in plaque by interventions was associated with increases in bacterial diversity, reduction in the Firmicutes/Bacteroidetes (F/B) ratio, and upregulation of Akkermansia. Upregulation in CYP7 isoform in the liver, ABC transporters, bile acid excretion, and the level of acetic acid, propionic acid, and butyric acid were also noted in several studies reducing plaque. These changes were also associated with attenuated inflammation and oxidative stress. In conclusion, an increase in the abundance of Akkermansia with diets rich in polyphenols, fiber, and grains is likely to reduce plaque burden in patients suffering from CVD.

Pharmacological attributes of Bacopa monnieri extract: Current updates and clinical manifestation

Bacopa monnieri has been used for centuries in Ayurvedic medicine, alone or in combination with other herbs, as a memory and learning enhancer, sedative, and anti-epileptic. This review aimed to highlight the health benefits of B. monnieri extracts (BME), focusing on anti-cancer and neurodegenerative diseases. We examined the clinical studies on phytochemistry and pharmacological application of BME. We further highlighted the mechanism of action of these extracts in varying types of cancer and their therapeutic implications. In addition, we investigated the underlying molecular mechanism in therapeutic interventions, toxicities, safety concerns and synergistic potential in cognition and neuroprotection. Overall, this review provides deeper insights into the therapeutic implications of Brahmi as a lead formulation for treating neurological disorders and exerting cognitive-enhancing effects.

Functional Medicine Approaches to Neurodegeneration

Neurodegenerative diseases impact more than 6 million Americans, and current predictions estimate the rates of neurodegenerative diseases will double in the next 30 years. These diseases are progressive with increasing loss of brain function throughout their course. Overtime, those suffering from neurodegenerative diseases will lose their ability to work and function efficiently in society. Families and society are burdened with skyrocketing costs to provide care for those who are unable to perform activities of daily living. There is an urgent need to develop treatment strategies to both reduce the incidence of neurodegenerative diseases and to delay the progression of the disease.

Pharmacotherapy of Alzheimer's disease: an overview of systematic reviews

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease and the most common cause of dementia. In this umbrella systematic review (SR), we summarized the efficacy of different pharmacological interventions in improving cognitive function in patients with AD.

METHODS

A systematic search was performed through the PubMed, Scopus, Embase, and Cochrane databases for SRs of studies assessing the efficacy of pharmacological interventions versus placebo in improving cognitive function in AD or mild cognitive impairment due to AD. The risk of bias (RoB) was assessed using the Risk of Bias in SRs (ROBIS) tool.

RESULTS

Out of 1748 articles found through the database survey, 33 SR articles were included. These studies assessed effects of immunotherapy, cholinesterase inhibitors (ChEIs), memantine, statins, lithium, nonsteroidal anti-inflammatory drugs (NSAIDs), antidiabetic agents, Cerebrolysin, RAS-targeting antihypertensive drugs (ARBs and ACEIs), psychostimulants, glycogen synthase kinase 3 (GSK-3) inhibitors, melatonin, and herbal medications on cognitive function in AD patients. There was no notable overall RoB in 18 studies (54.5%), the RoB in 14 studies (42.4%) was high, and in one study (3.0%) it was unclear.

CONCLUSIONS

The use of ChEIs, including rivastigmine, galantamine, and donepezil, as well as memantine has demonstrated a positive impact on improving cognitive outcomes of AD patients, but no considerable effects were found for immunotherapies. Melatonin, statins, antihypertensive drugs, antidiabetic agents, Cerebrolysin, psychostimulants, and some herbal drugs such as Danggui-Shaoyao-San and Ginkgo biloba seem to be effective in improving cognitive function of AD patients, but the evidence in this regard is limited.

Ginkgo biloba in the Aging Process: A Narrative Review

Neurodegenerative diseases, cardiovascular disease (CVD), hypertension, insulin resistance, cancer, and other degenerative processes commonly appear with aging. Ginkgo biloba (GB) is associated with several health benefits, including memory and cognitive improvement, in Alzheimer's disease (AD), Parkinson's disease (PD), and cancer. Its antiapoptotic, antioxidant, and anti-inflammatory actions have effects on cognition and other conditions associated with aging-related processes, such as insulin resistance, hypertension, and cardiovascular conditions. The aim of this study was to perform a narrative review of the effects of GB in some age-related conditions, such as neurodegenerative diseases, CVD, and cancer. PubMed, Cochrane, and Embase databases were searched, and the PRISMA guidelines were applied. Fourteen clinical trials were selected; the studies showed that GB can improve memory, cognition, memory scores, psychopathology, and the quality of life of patients. Moreover, it can improve cerebral blood flow supply, executive function, attention/concentration, non-verbal memory, and mood, and decrease stress, fasting serum glucose, glycated hemoglobin, insulin levels, body mass index, waist circumference, biomarkers of oxidative stress, the stability and progression of atherosclerotic plaques, and inflammation. Therefore, it is possible to conclude that the use of GB can provide benefits in the prevention and treatment of aging-related conditions.

The Efficacy and Safety of Alzheimer's Disease Therapies: An Updated Umbrella Review

BACKGROUND

Evidence summaries for efficacy and safety of frequently employed treatments of Alzheimer's disease (AD) are sparse.

OBJECTIVE

We aimed to perform an updated umbrella review to identify an efficacious and safe treatment for AD patients.

METHODS

We conducted a search for meta-analyses and systematic reviews on the Embase, PubMed, The Cochrane Library, and Web of Science to address this knowledge gap. We examined the cognitive functions, behavioral symptoms, global clinical assessment, and Activities of Daily Living as efficacy endpoints, and the incidence of adverse events as safety profiles.

RESULTS

Sixteen eligible papers including 149 studies were included in the umbrella review. The results showed that AChE inhibitors (donepezil, galantamine, rivastigmine, Huperzine A), Ginkgo biloba, and cerebrolysin appear to be beneficial for cognitive, global performances, and activities of daily living in patients with AD. Furthermore, anti-Aβ agents are unlikely to have an important effect on slowing cognitive or functional impairment in mild to moderate AD.

CONCLUSION

Our study demonstrated that AChE inhibitors, Ginkgo biloba, and cerebrolysin are the optimum cognitive and activities of daily living medication for patients with AD.

Use of complementary medicines and lifestyle approaches by people living with dementia: Exploring experiences, motivations and attitudes

BACKGROUND

Lack of effective treatments for chronic conditions is associated with high rates of complementary medicine (CM) use. However, little is known about CM use for dementia.

AIMS AND OBJECTIVES

The aim of this study was to explore the experiences, motivations, and attitudes towards CM use by people living with dementia in an Australian setting.

DESIGN

This study had a qualitative research design; quantitative demographic information was also collected.

METHODS

In-depth interviews were conducted with people living with dementia and their caregivers (N = 18). A thematic (inductive) analysis approach was taken to interpret data.

RESULTS

Three in four participants used CM for dementia, spending ~AUD$100/month (USD$70/month). Within three overarching themes, a range of sub-themes was identified: (1) CM knowledge and use: people living with dementia and caregivers understanding of CM, types of CM used, and CM usage patterns; (2) Self-determined reasons for use/non-use: maintain or improve quality of life, hope, management of dementia symptoms, level of awareness, willingness and evidence, perceptions on efficacy and safety of CM, experiences of conventional medicine, and holistic approach to wellness; (3) External determinants of use: information on CM, relationship influences on CM use, and experiences with General Practitioners (GPs) and CM.

CONCLUSION

Findings highlight that CM use is widespread and positively viewed by people living with dementia and their caregivers. Decisions regarding CM use were based on personal opinions. Findings have important implications for conversations with health professionals regarding CM use by people living with dementia to improve communication, health literacy, and reduce the risk of adverse effects through polypharmacy.

IMPLICATIONS FOR PRACTICE

This study showed that CM is a valued approach for dementia management by people living with dementia, their families, and healthcare providers. Future international research is required to evaluate the efficacy and safety of these approaches and promote accurate advice in nursing care.

Study on Mechanism of Ginkgo biloba L. Leaves for the Treatment of Neurodegenerative Diseases Based on Network Pharmacology

Ginkgo biloba L. leaves (GBLs), as widely used plant extract sources, significantly improve cognitive, learning and memory function in patients with dementia. However, few studies have been conducted on the specific mechanism of Neurodegenerative diseases (NDs). In this study, network pharmacology was employed to elucidate potential mechanism of GBLs in the treatment of NDs. Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) was used to obtain the chemical components in accordance with the screening principles of oral availability and drug-like property. Potential targets of GBLs were integrated with disease targets, and intersection targets were exactly the potential action targets of GBLs for treating NDs; these key targets were enriched and analyzed by the protein protein interaction (PPI) analysis and molecular docking verification. Key genes were ultimately used to find the biological pathway and explain the therapeutic mechanism by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Twenty-seven active components of GBLs may affect biological processes such as oxidative reactions and activate transcription factor activities. These components may also affect 120 metabolic pathways, such as the PI3K/AKT pathway, by regulating 147 targets, including AKT1, ALB, HSP90AA1, PTGS2, MMP9, EGFR and APP. By using the software iGEMDOCK, the main target proteins were found to bind well to the main active components of GBLs. GBLs have the characteristics of multi-component and multi-target synergistic effect on the treatment of NDs, which preliminarily predicted its possible molecular mechanism of action, and provided the basis for the follow-up study.

A RNA-seq approach for exploring the protective effect of ginkgolide B on glutamate-induced astrocytes injury

ETHNOPHARMACOLOGICAL RELEVANCE

There is substantial experimental evidence to support the view that Ginkgo biloba L. (Ginkgoaceae), a traditional Chinese medicine known to treating stroke, has a protective effect on the central nervous system and significantly improves the cognitive dysfunction caused by disease, including alzheimer disease (AD), vascular dementia, and diabetic encephalopathy. Although a number of studies have reported that ginkgolide B (GB), a diterpenoid lactone compound extracted from Ginkgo biloba leaves, has neuroprotective effects, very little research has been performed to explore its potential pharmacological mechanism on astrocytes under abnormal glutamate (Glu) metabolism in the pathological environment of AD.

AIM OF THE STUDY

We investigated the protective effect and mechanism of GB on Glu-induced astrocytes injury.

METHODS

Astrocytes were randomly divided into the control group, Glu group, GB group, and GB + IWP-4 group.The CCK-8 assay was used to determine relative cell viability in vitro. Furthermore, RNA sequencing (RNA-seq) was performed to assess the preventive effects of GB in the Glu-induced astrocyte model and reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to validate the possible molecular mechanisms. The effects of GB on the Glu transporter and Glu-induced apoptosis of astrocytes were studied by RT-qPCR and western blot.

RESULTS

GB attenuated Glu-induced apoptosis in a concentration-dependent manner, while the Wnt inhibitor IWP-4 reversed the protective effect of GB on astrocytes. The RNA-seq results revealed 4,032 differential gene expression profiles; 3,491 genes were up-regulated, and 543 genes were down-regulated in the GB group compared with the Glu group. Differentially expressed genes involved in a variety of signaling pathways, including the Hippo and Wnt pathways have been associated with the development and progression of AD. RT-qPCR was used to validate 14 key genes, and the results were consistent with the RNA-seq data. IWP-4 inhibited the regulation of GB, disturbed the apoptosis protective effect on astrocytes, and promoted Glu transporter gene and protein expression caused by Glu.

CONCLUSION

Our findings demonstrate that GB may play a protective role in Glu-induced astrocyte injury by regulating the Hippo and Wnt pathways. GB was closely associated with the Wnt pathway by promoting expression of the Glu transporter and inhibiting Glu-induced injury in astrocytes.

Enhanced anti-amnestic effect of donepezil by Ginkgo biloba extract (EGb 761) via further improvement in pro-cholinergic and antioxidative activities

ETHNOPHARMACOLOGICAL RELEVANCE

EGb 761 is a standardized dry extract of Ginkgo biloba L. leaves traditionally used by Eastern Asia and has been associated with beneficial effects on neurodegeneration disorders, including Alzheimer's disease.

AIM OF THE STUDY

Since beneficial interactions between EGb 761 and donepezil have been observed in previous clinical studies, the current study was proposed aiming to further explore related mechanisms from both pharmacokinetics and pharmacodynamics aspects.

MATERIALS AND METHODS

Pharmacodynamic interactions were studied in scopolamine-induced cognitive impairment rats received two-weeks treatment of vehicle, EGb 761 and/or donepezil by the Morris water maze test and ex vivo evaluation of biomarkers of cholinergic transmission and oxidative stress in rat brain. In the meantime, pharmacokinetic profiles of donepezil and bilobalide were obtained and compared among all treatment groups. In addition, impact of the bioavailable EGb 761 components on donepezil brain penetration was evaluated with the hCMEC/D3 cell monolayer model.

RESULTS

Scopolamine-induced rats with co-treatment of EGb 761 and donepezil had significantly improved cognitive function in the Morris water maze test with increased brain levels of superoxide dismutase and decreased brain levels of acetylcholinesterase and malondialdehyde than that with treatment of only EGb 761 or donepezil. Despite such beneficial pharmacodynamics outcomes, the two-week co-treatment of EGb 761 and donepezil did not alter the plasma pharmacokinetics and brain uptake of donepezil or bilobalide, which was further verified in the hCMEC/D3 monolayer model.

CONCLUSION

Co-administration of EGb 761 and donepezil exerted better anti-amnestic effect via further enhanced pro-cholinergic and antioxidative effects of EGb 761 or donepezil in scopolamine-induced cognitive impairment rat without alteration in their systemic/brain exposure.

Efficacy and safety of ginkgo preparation in patients with vascular dementia: A protocol for systematic review and meta-analysis

BACKGROUND

Vascular dementia has become the second most common type of dementia after Alzheimer disease. At present, there is no uniform standard for VaD treatment guidelines among countries. The efficacy of ginkgo biloba in the treatment of vascular dementia is still controversial. The purpose of this study is to evaluate the effectiveness and safety of ginkgo biloba in the treatment of vascular dementia through meta-analysis.

METHODS

Six English databases (PubMed, Web of science, Medline, EBASE, Springer Cochrane Library, and WHO International Clinical Trials Registry Platform) and 4 Chinese databases (Wan fang Database, Chinese Scientific Journal Database, China National Knowledge Infrastructure Database(CNKI) and Chinese Biomedical Literature Database) will be searched normatively according to the rule of each database from the inception to August 1, 2020. Two reviewers will independently conduct article selection, data collection, and risk of bias evaluation. Any disagreement will be resolved by discussion with the third reviewer. Either the fixed-effects or random-effects model will be used for data synthesis based on the heterogeneity test. The change in the scores on mini-mental state examination, activity of daily living scale and Montreal cognitive assement will be used as the main outcome measure, Hamilton depression scale, Hastgawa dementia scale, blessed dementia scale, clinical dmentia rating scale as the secondary outcome. Treatment emergent symptom scale, general physical examination (temperature, pulse, respiration, blood pressure), Routine examination of blood, urine and stool, electrocardiogram, liver and kidney function examination as the security indexs. RevMan5.3.5 will be used for meta-analysis.

RESULTS

This study will provide high-quality evidence to assess the effectiveness and safety of ginkgo preparation for vascular dementia.

CONCLUSION

This systematic review will explore whether ginkgo preparation is an effective and safe intervention for vascular dementia.

ETHICS AND DISSEMINATION

Ethical approval are not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and will be shared on social media platforms. This review will be disseminated in a peer-reviewed journal or conference presentation.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42020167851.