Intestinal mucosal metabolites-guided detection of trace-level ginkgo biloba extract metabolome

A bibliometric and thematic analysis of the trends in the research on ginkgo biloba extract from 1985 to 2022

Background

Ginkgo biloba extract (GBE), a complementary and alternative medicine, has been widely used for disorders such as brain infarction, dementia, and coronary heart disease, in recent decades. Given its widespread clinical use, GBE has always been a vital research topic. However, there are no bibliometric analyses on this topic; furthermore, published reviews of GBE focus only on a specific research field or lack scientific and systematic evaluation. This study combined bibliometrics with thematic reviews by visual analysis to identify the current status of GBE research and to better identify research hotspots and trends in the past 40 years to understand future developments in basic and clinical research.

Methods

Articles and reviews on GBE were retrieved by topic from the Web of Science Core Collection from inception to 2022.12.01. Countries, institutions, authors, journals, references, and keywords in the field were visually analyzed using CiteSpace, Scimago Graphica, and VOSviewer software; then, these visualization results for references and keywords were clarified in detail by thematic reviews in subdivisions of the fields.

Results

In total, 2015 publications were included. The GBE-related literature has high volumes of publications and citations. The majority of literature is from China, and the USA cooperates most closely with other countries. In GBE research, Christen Yves is the most cited author, Phytotherapy Research is the most prolific journal, and the Journal of Ethnopharmacology is the most co-cited journal. Through a comprehensive analysis of keywords, references, and reviews, the quality of the meta-analysis of randomized controlled clinical trials of GBE in treating dementia was evaluated by the Risk of Bias in Systematic Reviews scale (ROBIS). Current research on GBE focuses on its pharmacological mechanisms, and neuroprotective application in diseases such as Alzheimer's disease, and glaucoma. Randomized controlled trials are the current research hotspot.

Conclusion

Research on GBE is flourishing; using bibliometric and thematic analysis, we identified its hotspots and trends. The pharmacological mechanisms and clinical applications of GBE are the focus of present and likely future research.

Time-Series-Dependent Global Data Filtering Strategy for Mining and Profiling of Xenobiotic Metabolites in a Dynamic Complex Matrix: Application to Biotransformation of Flavonoids in the Extract of Ginkgo biloba by Gut Microbiota

Efficient characterization of xenobiotic metabolites and their dynamics in a changing complex matrix remains difficult. Herein, we proposed a time-series-dependent global data filtering strategy for the rapid and comprehensive characterization of xenobiotic metabolites and their dynamic variation based on metabolome data. A set of data preprocessing methods was used to screen potential xenobiotic metabolites, considering the differences between the treated and control groups and the fluctuations over time. To further identify metabolites of the target, an in-house accurate mass database was constructed by potential metabolic pathways and applied. Taking the extract of Ginkgo biloba (EGB) co-incubated with gut microbiota as an example, 107 compounds were identified as flavonoid-derived metabolites (including 67 original from EGB and 40 new) from 7468 ions. Their temporal metabolic profiles and regularities were also investigated. This study provided a systematic and feasible method to elucidate and profile xenobiotic metabolism.

Pharmacokinetic, Metabolism, and Metabolomic Strategies Provide Deep Insight Into the Underlying Mechanism of Ginkgo biloba Flavonoids in the Treatment of Cardiovascular Disease

Ginkgo biloba, known as the "living fossil," has a long history of being used as botanical drug for treating cardiovascular diseases and the content of flavonoids as high as 24%. More than 110 different kinds of flavonoids and their derivatives have been separated from G. biloba, including flavones, flavonols, biflavonoids, catechins, and their glycosides, etc., all of which display the ability to dilate blood vessels, regulate blood lipids, and antagonize platelet activating factor, and protect against ischemic damage. At present, many types of preparations based on G. biloba extract or the bioactive flavonoids of it have been developed, which are mostly used for the treatment of cardiovascular diseases. We herein review recent progress in understanding the metabolic regulatory processes and gene regulation of cellular metabolism in cardiovascular diseases of G. biloba flavonoids. First, we present the cardioprotective flavonoids of G. biloba and their possible pharmacological mechanism. Then, it is the pharmacokinetic and liver and gut microbial metabolism pathways that enable the flavonoids to reach the target organ to exert effect that is analyzed. In the end, we review the possible endogenous pathways toward restoring lipid metabolism and energy metabolism as well as detail novel metabolomic methods for probing the cardioprotective effect of flavonoids of G. biloba.

HRPIF data mining based on data-dependent/independent acquisition for Rhei Radix et Rhizoma metabolite screening in rats

In traditional Chinese medicine (TCM), components with identical nuclei often share structural similarity, indicating the possibility of similar second-level mass spectrometry (MS/MS) fragments. High-resolution product-ion filter (HRPIF) technique can be utilized to identify metabolites, with similar fragments, in vivo. In principle, this technique applies to TCM; however, its application has been restricted due to the limitations of traditional MS/MS data acquisition. Therefore, a novel analysis strategy, based on data-dependent acquisition (DDA) and data-independent acquisition (DIA) datasets, has been developed for the determination of template product ions and efficient non-targeted identification of TCM-related components in vivo by HRPIF and background subtraction (BS). This DDA-DIA combination strategy, taking Rhei Radix et Rhizoma as a test case, identified 71 anthraquinone prototype components in vitro (36 of which were discovered for the first time), and 45 related components in vivo, confirming glucuronidation and sulfation as the main reactions. The developed strategy could rapidly identify TCM-related components in vivo with high sensitivity, indicating the immense importance of this novel HRPIF data mining technology in TCM analysis.

Development and evaluation of a simultaneous strategy for pyrimidine metabolome quantification in multiple biological samples

Pyrimidines are critical nutrients and key biomolecules in nucleic acid biosynthesis and carbohydrate and lipid metabolism. Here, we proposed the concept of the pyrimidine metabolome, which covers 14 analytes in pyrimidine de novo and salvage synthetic pathways, and established a novel analytical strategy with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to efficiently illustrate pyrimidine transient distribution and dynamic balance. The lower limits of quantification (LLOQs) of all analytes were less than 10 ng/mL. Acceptable inter- and intra-day relative deviation (<15%) was detected, and good stability was obtained under different storage conditions. Metabolomics analysis revealed pyrimidine metabolic diversity in the plasma and brain among species, and a visualization strategy exhibited that pyrimidine biosynthetic metabolism is quite active in brain. Distinct metabolic features were also observed in cells with pyrimidine metabolomic disorders during proliferation and apoptosis. Absolute concentrations of pyrimidine metabolites in different bio-samples offered reference data for future pyrimidine studies.

Classification-based strategies to simplify complex traditional Chinese medicine (TCM) researches through liquid chromatography-mass spectrometry in the last decade (2011-2020): Theory, technical route and difficulty

The difficulty of traditional Chinese medicine (TCM) researches lies in the complexity of components, metabolites, and bioactivities. For a long time, there has been a lack of connections among the three parts, which is not conducive to the systematic elucidation of TCM effectiveness. To overcome this problem, a classification-based methodology for simplifying TCM researches was refined from literature in the past 10 years (2011-2020). The theoretical basis of this methodology is set theory, and its core concept is classification. Its starting point is that "although TCM may contain hundreds of compounds, the vast majority of these compounds are structurally similar". The methodology is composed by research strategies for components, metabolites and bioactivities of TCM, which are the three main parts of the review. Technical route, key steps and difficulty are introduced in each part. Two perspectives are highlighted in this review: set theory is a theoretical basis for all strategies from a conceptual perspective, and liquid chromatography-mass spectrometry (LC-MS) is a common tool for all strategies from a technical perspective. The significance of these strategies is to simplify complex TCM researches, integrate isolated TCM researches, and build a bridge between traditional medicines and modern medicines. Potential research hotspots in the future, such as discovery of bioactive ingredients from TCM metabolites, are also discussed. The classification-based methodology is a summary of research experience in the past 10 years. We believe it will definitely provide support and reference for the following TCM researches.

Advances in the chemical constituents and chemical analysis of Ginkgo biloba leaf, extract, and phytopharmaceuticals

Ginkgo biloba leaf (GBL) is an important botanical drug that can be used for treating many diseases. This review summarizes the reported chemical constituents from GBL or Ginkgo biloba extract (GBE) to date, as well as the recent advances in the extraction, purification, qualitative and quantitative analysis methods (from 2015 to 2020). To date, about 110 flavonoids have been reported to have unambiguous structures, including flavonol and its glycosides, flavone and its glycosides, flavanone and its glycosides, isoflavone and its glycosides, flavan-3-ols, bioflavonoids, and biginkgosides. In recent years, in addition to new flavonoids, new terpenoids and lignan have been also isolated from GBL. Further, several extraction and purification methods have been described and compared. Quantitative analysis of the constituents have been mainly carried out by high-performance liquid chromatography with different detector methods. Many studies have focused on variations of compounds contents in GBL from different regions, tree ages, or collection times, which provide references for the selection of GBL. Liquid chromatography-mass spectrometry coupled with activity assay methods were used to on-line screen the bioactive compounds from GBL or its phytopharmaceuticals. The application of other analytical technologies such as MS imaging, supercritical fluid chromatography, capillary electrophoresis, quantitative nuclear magnetic resonance, and spectroscopy, has also been discussed. This review of the chemical constituents and analytical methods of Ginkgo will provide a reference for the research on the quality control and discovery of effective constituents for GBL and its related phytopharmaceuticals.

Neuroprotective effects of Ginkgo biloba dropping pills in Parkinson's disease

Parkinson’s disease (PD) is the second most common neurodegenerative disease in the world; however, it lacks effective and safe treatments. Ginkgo biloba dropping pill (GBDP), a unique Chinese G. biloba leaf extract preparation, exhibits antioxidant and neuroprotective effects and has a potential as an alternative therapy for PD. Thus, the aims of this study were to evaluate the effects of GBDP in in vitro and in vivo PD models and to compare the chemical constituents and pharmacological activities of GBDP and the G. biloba extract EGb 761. Using liquid chromatography tandem-mass spectrometry, 46 GBDP constituents were identified. Principal component analysis identified differences in the chemical profiles of GBDP and EGb 761. A quantitative analysis of 12 constituents showed that GBDP had higher levels of several flavonoids and terpene trilactones than EGb 761, whereas EGb 761 had higher levels of organic acids. Moreover, we found that GBDP prevented 6-hydroxydopamine-induced dopaminergic neuron loss in zebrafish and improved cognitive impairment and neuronal damage in methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced PD mice. Although similar effects were observed after EGb 761 treatment, the neuroprotective effects were greater after GBDP treatment on several endpoints. In addition, in vitro results suggested that the Akt/GSK3β pathway may be involved in the neuroprotective effects of GBDP. These findings demonstrated that GBDP have potential neuroprotective effects in the treatment of PD.

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GBDP is composed of 46 constituents.

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Content of 12 constituents were different between GBDP and EGb 761.

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GBDP attenuated neurological deficits in zebrafish and mice PD models.

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GBDP prevented PD through anti-apoptosis and Akt/GSK3β signaling pathways.

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GBDP might be a potential therapeutic agent for PD.