Effectiveness and Safety Profile of Ginkgo biloba Standardized Extract (EGb761®) in Patients with Amnestic Mild Cognitive Impairment

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.

Mechanisms of multi-omics and network pharmacology to explain traditional chinese medicine for vascular cognitive impairment: A narrative review

BACKGROUND

The term "vascular cognitive impairment" (VCI) describes various cognitive conditions that include vascular elements. It increases the risk of morbidity and mortality in the elderly population and is the most common cognitive impairment associated with cerebrovascular disease. Understanding the etiology of VCI may aid in identifying approaches to target its possible therapy for the condition. Treatment of VCI has focused on vascular risk factors. There are no authorized conventional therapies available right now. The medications used to treat VCI are solely approved for symptomatic relief and are not intended to prevent or slow the development of VCI.

PURPOSE

The function of Chinese medicine in treating VCI has not yet been thoroughly examined. This review evaluates the preclinical and limited clinical evidence to comprehend the "multi-component, multi-target, multi-pathway" mechanism of Traditional Chinese medicine (TCM). It investigates the various multi-omics approaches in the search for the pathological mechanisms of VCI, as well as the new research strategies, in the hopes of supplying supportive evidence for the clinical treatment of VCI.

METHODS

This review used the Preferred Reporting Items for Preferred reporting items for systematic reviews and meta-analyses (PRISMA) statements. Using integrated bioinformatics and network pharmacology approaches, a thorough evaluation and analysis of 25 preclinical studies published up to July 1, 2023, were conducted to shed light on the mechanisms of TCM for vascular cognitive impairment. The studies for the systematic review were located using the following databases: PubMed, Web of Science, Scopus, Cochrane, and ScienceDirect.

RESULTS

We discovered that the multi-omics analysis approach would hasten the discovery of the role of TCM in the treatment of VCI. It will explore components, compounds, targets, and pathways, slowing the progression of VCI from the perspective of inhibiting oxidative stress, stifling neuroinflammation, increasing cerebral blood flow, and inhibiting iron deposition by a variety of molecular mechanisms, which have significant implications for the treatment of VCI.

CONCLUSION

TCM is a valuable tool for developing dementia therapies, and further research is needed to determine how TCM components may affect the operation of the neurovascular unit. There are still some limitations, although several research have offered invaluable resources for searching for possible anti-dementia medicines and treatments. To gain new insights into the molecular mechanisms that precisely modulate the key molecules at different levels during pharmacological interventions-a prerequisite for comprehending the mechanism of action and determining the potential therapeutic value of the drugs-further research should employ more standardized experimental methods as well as more sophisticated science and technology. Given the results of this review, we advocate integrating chemical and biological component analysis approaches in future research on VCI to provide a more full and objective assessment of the standard of TCM. With the help of bioinformatics, a multi-omics analysis approach will hasten the discovery of the role of TCM in the treatment of VCI, which has significant implications for the treatment of VCI.

Combined treatment with Ginkgo biloba extract EGb 761 plus acetylcholinesterase inhibitors improved cognitive function and neuropsychiatric symptoms in patients with mild cognitive impairment

Introduction

Mild cognitive impairment (MCI) is a neurocognitive state between normal aging and dementia. There is currently no approved treatment for MCI, with acetylcholinesterase inhibitors (AChEI) being the commonly prescribed drugs. The Ginkgo biloba extract EGb 761 is an herbal remedy used for cognitive disorders, including dementia. This study aims to explore the potential synergistic effect of combination therapy with EGb 761 plus AChEI in patients with amnestic MCI in a real-life setting.

Methods

We retrospectively identified 133 patients with amnestic MCI who were attending a memory clinic. Patients had received treatment with any of the following drugs: G. biloba extract EGb 761, donepezil, galantamine, or rivastigmine at their standard doses. Subjects were divided into three treatment groups: EGb 761, AChEI, and EGb 761+AChEI. Patients were assessed by Mini-Mental State Examination (MMSE), Rey Auditory Verbal Learning Test (RAVLT), Symbol Digit Modalities Test, Boston Naming Test, Trail Making Test (TMT Parts A and B), Letter and Category Fluency Test (LFT, CFT), Neuropsychiatric Inventory (NPI), and Interview for Deterioration in Daily Living. Mixed-effects model analysis was carried out to evaluate changes in cognitive, functional, and behavioral outcomes over a 12-month follow-up.

Results

After 12 months, EGb 761+AChEI showed significant improvement in MMSE, RAVLT, CFT, TMT A-B, and NPI compared to AChEI and in MMSE and RAVLT compared to EGb 761. At 12 months, EGb 761 was superior to AChEI on the CFT, TMT A-B, and NPI.

Discussion

Our findings suggest that combined therapy with EGb 761 plus AChEI may provide added cognitive and functional benefits in patients with MCI and provides additional real-world evidence for the combined use of EGb 761 and anti-dementia drugs in patients with MCI. This study can serve as a model for the design of clinical trials that help to support the combined use of EGb 761 and anti-dementia drugs in patients with MCI.

Antioxidative role of Traditional Chinese Medicine in Parkinson's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Neuroprotective Traditional Chinese Medicine (TCM) has been practiced in alternative medicine from early days. TCM-derived neuroprotective compounds, such as Chrysin, Cannabidiol, Toonasinoids, and β-asaron, exert significant effectiveness's towards Parkinson's disease (PD). Further, these neuroprotective TCM showed antioxidative, anti-inflammatory, anti-tumor, anti-septic, analgesic properties. Recent research showed that the reduction in the reactive oxygen species (ROS) decreased the α-synuclein (α-syn) toxicity and enhanced the dopaminergic neuron regenerations, the main hallmarks of PD. Therefore, the neuroprotective effects of novel TCM due to its antiradical activities needed deep investigations.

AIMS OF THE STUDY

This review aims to enlighten the neuroprotective TCM and its components with their antioxidative properties to the scientific community for future research.

METHOD

The relevant information on the neuroprotective TCM was gathered from scientific databases (PubMed, Web of Science, Google Scholar, ScienceDirect, SciFinder, Wiley Online Library, ACS Publications, and CNKI). Information was also gained from MS and Ph.D. thesis, books, and online databases. The literature cited in this review dates from 2001 to June 2, 0201.

RESULTS

Novel therapies for PD are accessible, mostly rely on Rivastigmine and Donepezil, offers to slow down the progression of disease at an early stage but embraces lots of disadvantages. Researchers are trying to find a potential drug against PD, which is proficient at preventing or curing the disease progress, but still needed to be further identified. Oxidative insult and mitochondrial dysfunction are thought to be the main culprit of neurodegenerations. Reactive oxygen species (ROS) are the only causative agent in all interactions, leading to PD, from mitochondrial dysfunctions, α-syn aggregative toxicity, and DA neurons degenerations. It is evident from the redox balance, which seems an imperative therapeutic approach against PD and was necessary for the significant neuronal activities.

CONCLUSION

Our study is explaining the newly discovered TCM and their neuroprotective and antioxidative properties. But also bring up the possible treatment approaches against PD for future researchers.

Pharmacokinetics and brain distribution studies of 6-hydroxykynurenic acid and its structural modified compounds

OBJECTIVES

6-Hydroxykynurenic acid (6-HKA) is an organic acid component in extracts of Ginkgo biloba leaves and acts as a major contributor to neurorestorative effects, while its oral bioavailability was low. Therefore, using prodrug method to improve the bioavailability and brain content of 6-HKA is significant.

METHODS

Three structural modified compounds of 6-HKA were synthesized, and ultra performance liquid chromatography-tandem mass spectrometry methods for quantification of these structural modified compounds in rat plasma and rat brain homogenate were established and comprehensively validated. The methods were effectively applied to investigate the effects of structural modification on apparent permeability coefficients in cells, the pharmacokinetics and the brain distribution in rats.

KEY FINDINGS

The results illustrated that esterification can greatly improve the apparent permeability coefficient and bioavailability of 6-HKA. Comparing with direct oral administration of 6-HKA, the bioavailability of isopropyl ester was greatly improved (from 3.96 ± 1.45% to 41.8 ± 15.3%), and the contents of 6-HKA in rat brains (49.7 ± 9.2 ng/g brain) were significantly higher after oral administration.

CONCLUSIONS

The bioavailability and the brain content of 6-HKA can be improved by the prodrug method. Among three structural modified compounds, isopropyl-esterified 6-HKA was the most promising treatment.