Anti-Cancer Properties of Ginkgolic Acids in Human Nasopharyngeal Carcinoma CNE-2Z Cells via Inhibition of Heat Shock Protein 90

Ginkgo biloba L. has been used in traditional Chinese medicine (TCM) for thousands of years. However, the anti-cancer properties of ginkgolic acids (GAS) isolated from G. biloba have not been investigated in human nasopharyngeal carcinoma cells. In this study, GAS exhibited an inhibitory effect on the ATPase activity of heat shock protein 90 (Hsp90) and anti-proliferative activities against four human cancer cell lines, with IC50 values ranging from 14.91 to 23.81 μg·mL−1. In vivo experiments confirmed that GAS inhibited tumor growth in CNE-2Z cell-xenografted nude mice with low hepatotoxicity. We further demonstrated that GAS suppressed migration and invasion and induced the apoptosis of CNE-2Z cells by inducing the degradation of Hsp90 client proteins (MMP-2, MMP-9, Her-2, c-Raf, Akt, and Bcl-2). Together, GAS are new Hsp90 inhibitors by binding to Hsp90 (hydrogen bond and hydrophobic interaction). Thus, GAS from G. biloba might represent promising Hsp90 inhibitors for the development of anti-nasopharyngeal carcinoma agents.

Isovitexin Inhibits Ginkgolic Acids-Induced Inflammation Through Downregulating SHP2 Activation

It has been reported that Celtis sinensis Pers. is employed as a folk medicine for the treatment of inflammatory diseases. But the mechanism supporting its use as anti-inflammatory remains unclear. To investigate the anti-inflammatory of Celtis sinensis Pers. ICR mice were provided Celtis sinensis Pers. leaf extract (CLE) at 100, 200 mg/kg after ginkgolic acids (GA) sensitization. Our data showed that CLE and the main flavonoid isovitexin in CLE could ameliorate GA-induced contact dermatitis in mice. Ear swelling, inflammatory cell infiltration and splenomegaly were inhibited significantly by isovitexin, while the weight loss of mice in the isovitexin-treated group was much better than that in the dexamethasone-treated group (positive control drug). It has been reported in previous research that GA-induced inflammation is closely related to the T cell response. Therefore, T cells were the focus of the anti-inflammatory effect of isovitexin in this paper. The in vivo results showed that isovitexin (10, 20 mg/kg) inhibited the expression of proinflammatory cytokines (TNF-α, IFN-γ, IL-2 and IL-17A) in lymph nodes, inhibited the secretion of cytokines into the serum from mice with contact dermatitis and promoted the expression of apoptosis-related proteins. In vitro, isovitexin also induced apoptosis and inhibited proinflammatory cytokine expression in Con A-activated T cells. Further study showed that the MAPK and STAT signaling pathways and the phosphorylation of SHP2 were inhibited by isovitexin. Both molecular docking and biological experiments indicated that SHP2 may be an anti-inflammatory target of isovitexin in T cells. Taken together, isovitexin can serve as a potential natural agent for the treatment or prevention of GA-induced inflammatory problems.

Isovitexin, a main Flavonoid Compound from Celtis Sinensis Pers. Leaves, Exerts Activity Against Inflammation caused by Contacting Ginkgolic Acids in Ginkgo Fruit through Downregulating SHP2 Activation

It has been reported that Celtis sinensis Pers. is employed as a folk medicine for the treatment of inflammation diseases. But the mechanism supporting its use as anti-inflammatory remain unclear. To investigate the anti-inflammatory of Celtis sinensis Pers. ICR mice were provided Celtis sinensis Pers. leaf extract (CLE) at 100, 200mg/kg after ginkgolic acids (GA) sensitization. Our data showed that CLE and the main flavonoid isovitexin in CLE could ameliorate GA-induced contact dermatitis in mice. Ear swelling, inflammatory cell infiltration and splenomegaly were inhibited significantly by isovitexin, while the weight loss of mice in the isovitexin-treated group was much better than that in the dexamethasone-treated group (positive control drug). It has been reported in previous research that GA-induced inflammation is closely related to the T cell response. Therefore, T cells were the focus of the anti-inflammatory effect of isovitexin in this paper. The in vivo results showed that isovitexin (10, 20mg/kg) inhibited the expression of proinflammatory cytokines (TNF-α, IFN-γ, IL-2 and IL-17A) in lymph nodes, inhibited the secretion of cytokines into the serum from mice with contact dermatitis and promoted the expression of apoptosis-related proteins. In vitro, isovitexin also induced apoptosis and proinflammatory cytokine expression in Con A-activated T cells. Further study showed that the MAPK and STAT signaling pathways and the phosphorylation of SHP2 were inhibited by isovitexin. Both molecular docking and biological experiments indicated that SHP2 may be an anti-inflammatory target of isovitexin in T cells. Taken together, isovitexin can serve as a potential natural agent for the treatment or prevention of GA-induced inflammatory problems.

Ginkgolic Acids Confer Potential Anticancer Effects by Targeting Pro-Inflammatory and Oncogenic Signaling Molecules

Background: Medicinal plants and herbal preparations in the form of traditional medicines have been used in healthcare worldwide. The extracts of Ginkgo biloba L. seeds and leaves contain a complex mixture of numerous components, such as flavonol glycosides, terpene lactones, and a group of alkylphenols (anacardic or ginkgolic acids, cardanols and cardols) that have been a part of traditional Chinese medicine. These extracts are also sold as dietary supplements worldwide. G. biloba extract (EGb 761 and LI 1370) represent the standard form of G. biloba extract. Six different 6-alkylsalicylic acids (syn. ginkgolic acids) with alkyl substituents (C13:0, C15:0, C15:1, C17:1, and C17:2) have been identified. Objective: To aim of this review is to unravel scientific evidences on anti-inflammatory and anticancer activities of ginkgolic acids to understand its therapeutic potential against inflammatory and oncologic diseases. Methods: A structured literature search was independently performed by the authors on PubMed, ScienceDirect, Scopus, and Web of Science. Accordingly, this review article critically analyses available scientific evidences on anti-inflammatory and anticancer activities of ginkgolic acids. Moreover, the review only included articles written in English language. Results: Several forms of ginkgolic acids, especially C13:0, C15:0 and C17:1, isolated from the leaves of G. biloba exhibited cytotoxic activity against a variety of human cancers by suppressing various pro-inflammatory signaling cascades and oncogenic transcription factors through multiple modes of action in various in vitro and in vivo preclinical models. Ginkgolic acids have also been reported to be potent post-translational small ubiquitin-related modifiers (SUMO)ylation inhibitors. Conclusion: In this review, we present updated information on the anti-inflammatory and anticancer properties of ginkgolic acids both in vitro and in vivo. Although ginkgolic acids show significant therapeutic potential in inflammatory and oncologic diseases, more investigations regarding the safety and efficacy of these natural agents are warranted before clinical transition.

Application of targeted 2D planar chromatography in the control of ginkgolic acids in some herbal drugs and dietary supplements

Two-step targeted 2D planar chromatographic method (2DTLC) was used in the determination of ginkgolic acids in pharmaceuticals and dietary supplements. The choice of the extraction method and the separation technique was guided by the formulation type (capsule, tablet, tincture) with expected low amounts of ginkgolic acids in the analyzed herbal samples. Separation of ginkgolic acids C15:1 and C17:1 on HPTLC RP18 WF254s was preceded by its separation from the sample matrix on TLC Si60 F254s. Mobile phases consisted of acetonitrile/water/formic acid (80:20:1, V/V/V) and n-heptane/ethyl acetate/formic acid (20:30:1, V/V/V), resp. Identification of separated compounds was based on 2D-TLC co-chromatography with reference substances and off-line 2D-TLC x HPLC-DAD-ESI-MS analysis. Quantification of ginkgolic acids C15:1 and C17:1 was conducted densitometrically. Among the analyzed products, the presence of ginkgolic acids was confirmed only in herbal drugs containing 60 % ethanolic tinctures of Ginkgo biloba leaves. The use of TLC in the quantification of ginkgolic acids C15:1 and C17:1 in ginkgo extracts was described for the first time.

Improvement of the Quality of Ginkgo biloba Leaves Fermented by Eurotium cristatum as High Value-Added Feed

Ginkgo biloba leaves are well known for their high content of nutrients and bioactive substances. However, unpleasant smell and a small number of ginkgolic acids greatly reduce the utilization of the leaves. In this work, solid-state fermentation of G. biloba leaves using Eurotium cristatum was studied by investigation of the nutrient changes and its feasibility as a functional feed. E. cristatum could grow on pure G. biloba leaves and the addition of excipients could significantly improve the growth of E. cristatum. The optimal medium was with 10% (w/w) of whole G. biloba seeds and the optimized water content, pH, inoculum size and fermentation time were 45% (w/w), 4.5, 4.76 × 107 CFU/100 g wet medium, and eight days, respectively. Under the optimal conditions, the spore number increased by about 40 times. The content of flavonoids was greatly increased by 118.6%, and the protein and polyprenyl acetates (PPAs) were increased by 64.9% and 10.6%, respectively. The ginkgolic acids, lignin, and cellulose were decreased by 52.4%, 38.5%, and 20.1% than before, respectively. Furthermore, the fermented G. biloba leaves showed higher antioxidant activity and held more aroma substances. Thus, G. biloba leaves fermented by E. cristatum have potential as s high value-added feed. This is the first investigation of E. cristatum fermentation on ginkgo leaves, which will facilitate the use of ginkgo leaves in the feed industry.