Ginkgo biloba Extracts: A Review of the Pharmacokinetics of the Active Ingredients

Molecular characterization of a novel mitovirus from the plant-pathogenic fungus Nigrospora oryzae

Here, we characterized a novel mitovirus from the fungus Nigrospora oryzae, which was named "Nigrospora oryzae mitovirus 3" (NoMV3). The NoMV3 genome is 2,492 nt in length with a G + C content of 33%, containing a single large open reading frame (ORF) using the fungal mitochondrial genetic code. The ORF encodes an RNA-dependent RNA polymerase (RdRp) of 775 amino acids with a molecular mass of 88.75 kDa. BLASTp analysis revealed that the RdRp of NoMV3 had 68.6%, 50.6%, and 48.6% sequence identity to those of Nigrospora oryzae mitovirus 2, Suillus luteus mitovirus 6, and Fusarium proliferatum mitovirus 3, respectively, which belong to the genus Unuamitovirus within the family Mitoviridae. Phylogenetic analysis based on amino acid sequences supported the classification of NoMV3 as a member of a new species in the genus Unuamitovirus within the family Mitoviridae.

A sustainable and efficient strategy for bioconverting naringin to L-rhamnose, 2R-naringenin, and kaempferol

The development of a sustainable and efficient bioconversion strategy is crucial for the full-component utilization of naringin. In this study, an engineering Pichia pastoris co-culture system was developed to produce L-rhamnose and 2S/2R-naringenin. By optimizing transformation conditions, the co-culture system could completely convert naringin while fully consuming glucose. The production of 2S/2R-naringenin reached 59.5 mM with a molar conversion of 99.2%, and L-rhamnose reached 59.1 mM with a molar conversion of 98.5%. In addition, an engineering Escherichia coli co-culture system was developed to produce 2R-naringenin and kaempferol from 2S/2R-naringenin. Maximal kaempferol production reached 1050 mg/L with a corresponding molar conversion of 99.0%, and 996 mg/L 2R-naringenin was accumulated. Finally, a total of 17.4 g 2R-naringenin, 18.0 g kaempferol, and 26.1 g L-rhamnose were prepared from 100 g naringin. Thus, this study provides a novel strategy for the production of value-added compounds from naringin with an environmentally safe process.

Ginkgo biloba L. exocarp petroleum ether extract inhibits methicillin-resistant Staphylococcus aureus by modulating ion transport, virulence, and biofilm formation in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

As reported in the Ancient Chinese Medicinal Books, Ginkgo biloba L. fruit has been used as a traditional Chinese medicine for the treatment asthma and cough or as a disinfectant. Our previous study demonstrated that G. biloba exocarp extract (GBEE), an extract of a traditional Chinese herb, inhibits the formation of methicillin-resistant Staphylococcus aureus (MRSA) biofilms. However, GBEE is a crude extract that contains many components, and the underlying mechanisms of purified GBEE fractions extracted with solvents of different polarities are unknown.

AIM OF THE STUDY

This study aimed to investigate the different components in GBEE fractions extracted with solvents of different polarities and their antibacterial effects and mechanisms against MRSA and Staphylococcus haemolyticus biofilms both in vitro and in vivo.

METHODS

The components in different fractions were detected by high-performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS). Microbroth dilution assays and time growth curves were used to determine the antibacterial effects of the fractions on 15 clinical bacterial isolates. Crystal violet staining, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to identify the fractions that affected bacterial biofilm formation. The potential MRSA targets of the GBEE fraction obtained with petroleum ether (PE), denoted GBEE-PE, were screened by transcriptome sequencing, and the gene expression profile was verified by quantitative polymerase chain reaction (qPCR).

RESULTS

HPLC-HRMS analysis revealed that the four GBEE fractions (extracted with petroleum ether, ethyl acetate, n-butanol, and water) contained different ginkgo components, and the antibacterial effects decreased as the polarity of the extraction solvent increased. The antibacterial activity of GBEE-PE was greater than that of the GBEE fraction extracted with ethyl acetate (EA). GBEE-PE improved H. illucens survival and reduced MRSA colonization in model mouse organs. Crystal violet staining and SEM and TEM analyses revealed that GBEE-PE inhibited MRSA and S. haemolyticus biofilm formation. Transcriptional analysis revealed that GBEE-PE inhibits MRSA biofilms by altering ion transport, cell wall metabolism and virulence-related gene expression. In addition, the LO2 cell viability and H. illucens toxicity assay data showed that GBEE-PE at 20 mg/kg was nontoxic.

CONCLUSION

The GBEE fractions contained different components, and their antibacterial effects decreased with increases in the polarity of the extraction solvent. GBEE-PE limited MRSA growth and biofilm formation by affecting ion transport, cell wall synthesis, and virulence-related pathways. This research provides a more detailed overview of the mechanism by which GBEE-PE inhibits MRSA both in vitro and in vivo and suggests that GBEE-PE is a new prospective antimicrobial with the potential to be used in MRSA therapeutics in the future.

Ginkgo biloba extract mitigates the neurotoxicity of AlCl3 in alzheimer rat's model: role of apolipoprotein E4 and clusterin genes in stimulating ROS generation and apoptosis

PURPOSE

Alzheimer's disease (AD) appears as a result of an increase in the accumulation of amyloid beta peptide (Aβ) and a decrease in neurotransmitters (acetylcholine) within the brain cells which may be due to increase in acetylcholinesterase (AchE) activity and change in expression of Apolipoprotein E4 (ApoE4) and Clusterin (Clu) genes. The aim of the present study was using natural products such as Ginkgo biloba (G. biloba) extract that has the potential to reduce Aβ formation and increase AchE inhibition with its ability to save neuronal DNA from damage.

METHODS

Sixty male aged rats were divided into six experimental groups exposed to AlCl3 to induce AD model and were treated with G. biloba extract. Collected brain tissues were used to assess the apoptosis rate, reactive oxygen species (ROS) generation, AchE inhibitory activity, expression alteration in ApoE4 and Clu genes, DNA fragmentations and gutathione peroxidase (GPx) activity.Results: The results exhibited that rats exposed to AlCl3 increased significantly rate of apoptosis, ROS formation, DNA fragmentation, up-regulation of ApoE4 and Clu genes as well as decrease of AchE inhibitory activity and GPx activity compared with those in control rats. However, treatment of AlCl3-rats with G. biloba extract improved the above neurotoxicity results induced by AlCl3 exposure.

CONCLUSIONS

It is therefore likely that G. biloba extract's protective properties against AD are due to its ability to activate the response against oxidative stress.

Topotecan and Ginkgolic Acid Inhibit the Expression and Transport Activity of Human Organic Anion Transporter 3 by Suppressing SUMOylation of the Transporter

Organic anion transporter 3 (OAT3), expressed at the basolateral membrane of kidney proximal tubule cells, facilitates the elimination of numerous metabolites, environmental toxins, and clinically important drugs. An earlier investigation from our laboratory revealed that OAT3 expression and transport activity can be upregulated by SUMOylation, a post-translational modification that covalently conjugates SUMO molecules to substrate proteins. Topotecan is a semi-synthetic derivative of the herbal extract camptothecin, approved by the FDA to treat several types of cancer. Ginkgolic acid (GA) is one of the major components in the extract of Ginkgo biloba leaves that has long been used in food supplements for preventing dementia, high blood pressure, and supporting stroke recovery. Both topotecan and GA have been shown to affect protein SUMOylation. In the current study, we tested our hypothesis that topotecan and GA may regulate OAT3 SUMOylation, expression, and transport function. Our data show that the treatment of OAT3-expressing cells with topotecan or GA significantly decreases the SUMOylation of OAT3 by 50% and 75%, respectively. The same treatment also led to substantial reductions in OAT3 expression and the OAT3-mediated transport of estrone sulfate, a prototypical substrate. Such reductions in cell surface expression of OAT3 correlated well with an increased rate of OAT3 degradation. Mechanistically, we discovered that topotecan enhanced the association between OAT3 and the SUMO-specific protease SENP2, a deSUMOylation enzyme, which contributed to the significant decrease in OAT3 SUMOylation. In conclusion, this study unveiled a novel role of topotecan and GA in inhibiting OAT3 expression and transport activity and accelerating OAT3 degradation by suppressing OAT3 SUMOylation. During comorbidity therapies, the use of topotecan or Ginkgo biloba extract could potentially decrease the transport activity of OAT3 in the kidneys, which will in turn affect the therapeutic efficacy and toxicity of many other drugs that are substrates for the transporter.

The molecular mechanisms of ginkgo (Ginkgo biloba) activity in signaling pathways: A comprehensive review

BACKGROUND

One of the most unique plants that have ever grown on the planet is Ginkgo biloba L., a member of the Ginkgoaceae family with no close living relatives. The existence of several differently structured components of G. biloba has increased the chemical variety of herbal therapy. Numerous studies that investigated the biochemical characteristics of G. biloba suggest this plant as a potential treatment for many illnesses.

PURPOSE

Review the molecular mechanisms involved in the signaling pathways of G. biloba activity in varied circumstances and its potential as a novel treatment for various illnesses.

METHODS

Studies focusing on the molecular processes and signaling pathways of compounds and extracts of G. biloba were found and summarized using the proper keywords and operators from Google Scholar, PubMed, Web of Science, and Scopus without time restrictions.

RESULTS

G. biloba exerts its effects through its anti-inflammatory, anti-apoptotic, anti-cancer, neuroprotective, cardioprotective, hepatoprotective, antiviral, antibacterial, pulmoprotective, renoprotective, anti-osteoporosis, anti-melanogenic, retinoprotective, otoprotective, adipogenic, and anti-adipogenic properties. The most important mechanisms involved in these actions are altering the elevation of ROS formation, inhibiting NADPH oxidases activation, altering the expression of antioxidant enzymes, downregulating MAPKs (p38 MAPK and ERK, and JNK) and AP-1, increasing cAMP, inactivating Stat5, activating the AMPK signaling pathway, affecting Stat3/JAK2, NF-κB, Nrf-2, mTOR, HGF/c-Met, Wnt/β-catenin and BMP signaling pathways, and changing the mitochondrial transmembrane potential, the Bax/Bcl-2 ratio, the release of Cyc from mitochondria to cytosol, the protein cleavage of caspases 3, 7, 8, 9, and 12, poly (ADP-ribose) polymerase, and MMPs levels.

CONCLUSIONS

G. biloba and its components have gained attention in recent years for their therapeutic benefits, such as their anti-inflammatory, antioxidant, anti-apoptotic, and apoptotic effects. By understanding their molecular mechanisms and signaling pathways, potential novel medicines might be developed in response to the rising public desire for new therapies.

Safety and efficacy of a feed additive consisting of a dry extract obtained from the leaves of Ginkgo biloba L. (ginkgo extract) for horses, dogs, cats, rabbits and guinea pigs (FEFANA asbl)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a feed additive obtained from the dried leaves of Ginkgo biloba L. (ginkgo extract) when used as a sensory additive in feed for horses, dogs, cats, rabbits and guinea pigs. Ginkgo extract contains ≥ 24% total flavonoids, ≥ 6% total terpene lactones and ≤ 1 mg/kg ginkgolic acids. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that ginkgo extract is safe for the target species at the following concentrations in complete feed: 2.8 mg/kg for horses and cats, 1.1 mg/kg for rabbits and guinea pigs, and 3.3 mg/kg for dogs. No safety concern would arise for the consumers from the use of ginkgo extract up to the highest level in feed which is considered safe for food-producing species (horses and rabbits). The additive should be considered as irritant to skin and eyes, and as a dermal and respiratory sensitiser. The use of the additive at the proposed level in feed for the target species is not considered to be a risk to the environment. While the available data indicate that Ginkgo preparations have a distinctive flavour profile, there is no evidence that the ginkgo extract would impart flavour to a food or feed matrix. Therefore, the FEEDAP Panel cannot conclude on the efficacy of the additive.

Therapeutic potential of clinically proven natural products in the management of dementia

Dementia is a common neurodegenerative disorder connected to damage to nerve cells in the brain. Although some conventional drugs are available for dementia treatments and are still sanctified for dementia patients, their short- and long-term side effects and other limitations make treating patients more challenging. The authors aimed to explain novel options for treating dementia with natural products and unravel some clinically proven natural products. This article systematically reviewed recent studies that have investigated the role of natural products and their bioactive compounds for dementia. PubMed Central, Scopus, and Google Scholar databases of articles were collected, and abstracts were reviewed for relevance to the subject matter.In this review, we provide mechanistic insights of clinically validated natural products, including like- Yokukansan, Souvenaid, BDW, Hupergene, Bacopa monnier, Omega-3, Tramiprostate and Palmitoylethanolamide with which have therapeutic efficacy against dementia in the management of dementia. As shown by studies, certain natural ingredients could be used to treat and prevent dementia. We strongly believe that the medicinal plants and phytoconstituents alone or in combination with other compounds would be effective treatments against dementia with lesser side effects as compared to currently available treatments. Moreover, these products should be studied further in order to develop novel dementia medications.

Efficacy and safety of standardized Ginkgo biloba extract as adjuvant therapy for intracerebral hemorrhage in China: A systematic review and meta-analysis

Objective

The aim of this study was to systematically review the clinical efficacy and safety of standardized Ginkgo biloba extract (GBE) in the adjuvant treatment of intracerebral hemorrhage (ICH).

Methods

Relevant RCTs on GBE as adjuvant therapy for ICH were searched in seven Chinese and English databases. Data extraction of the included literature was performed after duplicate checking and screening, and Stata 15.1 software was applied for data analysis.

Results

With a total of 19 RCTs, the meta-analysis results showed that: Compared with conventional treatment alone, GBE combined with conventional treatment had a higher effective rate; NIHSS score and CSS score were lower; The residual hematoma was less. The volume of cerebral edema was smaller. ADL score was higher. MoCA score was higher. The serum levels of hs-CRP, TNF-α and IL-6 were lower; No significant difference was observed in the incidence of adverse reactions between conventional treatment alone and GBE combined with conventional treatment.

Conclusion

This study suggests that GBE as adjuvant therapy for ICH has better efficacy and is relatively safe compared with conventional treatment alone. However, due to the quality and quantity of included studies, further validation by more methodologically rigorous and multi-center studies with larger sample sizes is needed.

Detecting and identifying pathogens and antagonistic bacteria associated with Ginkgo biloba leaf spot disease

Background

Leaf spot disease severely impacts Ginkgo biloba (G. biloba) yield and quality. While microbial agents offer effective and non-toxic biological control for plant diseases, research on controlling leaf spot disease in G. biloba is notably scarce.

Methods

The pathogenic fungi were isolated and purified from diseased and healthy leaves of G. biloba, Subsequent examinations included morphological observations and molecular identification via PCR techniques. A phylogenetic tree was constructed to facilitate the analysis of these pathogenic fungi, and Koch's postulates were subsequently employed to reaffirm their pathogenic nature. The antagonistic experiment was employed to select biocontrol bacteria, and subsequently, the isolated biocontrol bacteria and pathogenic fungi were inoculated onto healthy leaves to assess the inhibitory effects of the biocontrol bacteria.

Results

Two pathologies responsible for the leaf spot disease on G. biloba were identified as Botryosphaeria dothidea and Neofusicoccum parvum via the analysis of phylogenetic tree and the application of Koch's Postulates. Additionally, we isolated two strains of biocontrol bacteria, namely Bacillus velezensis and Bacillus amyloliquefaciens. Their average inhibitory zones were measured at 4.78 cm and 3.46 cm, respectively. The inhibition zone of B. velezensis against N. parvum was 4 cm. B. velezensis showed a stronger inhibitory effect compared to B. amyloliquefaciens on the development of lesions caused by B. dothidea via leaf culture experiment.

Conclusion

This research reports, for the first time, the presence of B. dothidea as a pathogenic fungus affecting G. biloba. Moreover, the biocontrol bacteria, B. velezensis and B. amyloliquefaciens, exhibited the capability to effectively inhibit the growth and reproduction of B. dothidea, indicating their promising potential as environmentally friendly biocontrol resources.

New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

Our continued works on the chemical constituents of Ginkgo biloba (G. biloba) leaves has led to the isolation of two novel phenylbutenoids (1, 2), along with five previously unidentified terpene glycosides (3-7). Among them, compounds 1 and 2 represent unique (Z)-phenylbutenoids, 3-6 are megastigmane glycosides, and 7 is identified as a rare bilobanone glycoside (Fig. 1). This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from G. biloba. The chemical structures of these compounds were elucidated through extensive spectroscopic analysis, including HR-ESI-MS and various 1D and 2D NMR experiments. Furthermore, the absolute configurations of these molecules were determined using Mosher's method, ECD experiments, and Cu-Kα X-ray crystallographic analyses.

An updated review of YAP: A promising therapeutic target against cardiac aging?

The transcriptional co-activator Yes-associated protein (YAP) functions as a downstream effector of the Hippo signaling pathway and plays a crucial role in cardiomyocyte survival. In its non-phosphorylated activated state, YAP binds to transcription factors, activating the transcription of downstream target genes. It also regulates cell proliferation and survival by selectively binding to enhancers and activating target genes. However, the upregulation of the Hippo pathway in human heart failure inhibits cardiac regeneration and disrupts astrogenesis, thus preventing the nuclear translocation of YAP. Existing literature indicates that the Hippo/YAP axis contributes to inflammation and fibrosis, potentially playing a role in the development of cardiac, vascular and renal injuries. Moreover, it is a key mediator of myofibroblast differentiation and fibrosis in the infarcted heart. Given these insights, can we harness YAP's regenerative potential in a targeted manner? In this review, we provide a detailed discussion of the Hippo signaling pathway and consolidate concepts for the development and intervention of cardiac anti-aging drugs to leverage YAP signaling as a pivotal target.

Ginkgo biloba extract promotes Treg differentiation to ameliorate ischemic stroke via inhibition of HIF-1α/HK2 pathway

The ischemic brain can dialogue with peripheral tissues through the immune system. Ginkgo biloba extract (EGb) was used to regulate various neurological disorders; however, the impact of EGb on ischemic stroke is still unclear. Here, we aimed to investigate whether immunomodulation has participated in the beneficial effects of EGb on ischemia/reperfusion (I/R) brain injury. Mice were orally administered with EGb once daily for 7 days before the induction of I/R. Neurobehavioral scores, infarct volume, and brain inflammation were determined. The proportion of CD4+ T cells was detected by flow cytometry. EGb significantly lowered neurobehavioral scores, infarct volume, and the level of inflammatory cytokines in I/R mice. Interestingly, EGb altered the proportion of CD4+ T cells, particularly increasing the proportion of Treg cells. Depletion of Treg cells weakened the neuroprotective effects of EGb on ischemic stroke; furthermore, EGb decreased the expression of HIF-1α and HK2 and promoted the differentiation of Treg cells in vitro. EGb suppressed the HIF-1α/HK2 signaling pathway to promote the differentiation of Treg cells and ameliorate ischemic stroke in mice. The expansion effect of EGb on Treg cells could be exploited as part of future stroke therapy.

Comprehensive Review of Nutraceuticals against Cognitive Decline Associated with Alzheimer's Disease

Nowadays, nutraceuticals are being incorporated into functional foods or used as supplements with nonpharmacological approaches in the prevention and management of several illnesses, including age-related conditions and chronic neurodegenerative diseases. Nutraceuticals are apt for preventing and treating such disorders because of their nontoxic, non-habit-forming, and efficient bioactivities for promoting neurological well-being due to their ability to influence cellular processes such as neurogenesis, synaptogenesis, synaptic transmission, neuro-inflammation, oxidative stress, cell death modulation, and neuronal survival. The capacity of nutraceuticals to modify all of these processes reveals the potential to develop food-based strategies to aid brain development and enhance brain function, prevent and ameliorate neurodegeneration, and possibly reverse the cognitive impairment observed in Alzheimer's disease, the most predominant form of dementia in the elderly. The current review summarizes the experimental evidence of the neuroprotective capacity of nutraceuticals against Alzheimer's disease, describing their mechanisms of action and the in vitro and in vivo models applied to evaluate their neuroprotective potential.

Efficacy of Herbal Medicines on Lung Function in Asthma: a systematic review and meta-analysis of randomized controlled trials

Objectives

The present study was designed to conduct a comprehensive systematic review and meta-analysis to assess the efficacy of herbal medicines as add-on therapy on lung function in asthmatic patients.

Methods

A comprehensive search of online databases was performed up to December 2021 to identify randomized controlled trials that used orally herbal preparations for asthma as add-on therapy. Studies were assessed for methodological quality using the Cochrane Collaboration's Risk of Bias tool. The main outcome was percent predicted value of forced expiratory volume (% predicted FEV1). Pooled weighted mean difference (WMD) estimate with corresponding 95% confidence interval (CI) was calculated using inverse-variance weights method while random effects meta-analysis was used, taking into account clinical and conceptual heterogeneity.

Results

As a result, 1,525 studies were identified. 169 studies were reviewed in-depth and 23 studies met our systematic review inclusion criteria. Finally, nine randomized controlled trials were included in the meta-analysis. Findings indicated that use of herbal medicines in patients with asthma significantly improved % predicted FEV1 (WMD 3.73, 95% CI 1.76-5.70), with no evidence for significant heterogeneity (p = 0.56 [Q statistic], I² = 0.0%). In subgroup analysis by age, improvement in % predicted FEV1 was higher and significant in adults (WMD 5.16; 95% CI 2.68-7.63) compared to children (WMD = 1.27; 95% CI -1.98-4.51). Sensitivity analysis showed the significant effect of herbal medicine consumption on improving FEV1 was consistently (range of summary WMDs 3.27-4.59), indicating that the meta-analysis model was robust. There was no evidence of publication bias both visually and statistically.

Conclusion

Findings support, the complementary use of herbal medicines resulted in significant improvement in the lung function compared to standard treatment in asthmatic patients with no considerable adverse events. This improvement is more likely to be observed amongst adults.

The enzymatic modification of whey-proteins for spray drying encapsulation of Ginkgo-biloba extract

Ginkgo biloba extract (GBLE) contains many bioactives including flavonoids and terpene trilactones that play some pharmacological roles. These compounds are sensitive to operating conditions; so, encapsulation is a suitable approach to protect them. In this study, different carriers including maltodextrin (MD), and its combination with gum-Arabic (MD-GA), whey protein concentrate (MD-WPC), and whey-protein hydrolysate (MD-HWPC) were used to encapsulate GBLE. Powder production yield, physicochemical/functional characteristics, physical stability and flowability of particles were affected by the type and composition of carriers. FTIR results indicated the placement of phenolic compounds in the carrier matrix. The SEM images also showed the morphological changes of particles (especially the size, indentation and surface shrinkage) under the influence of various carriers. Microencapsulated powders formulated using MD-HWPC showed the highest values of TPC, DPPH, and ABTS and a lighter color which determined the suitability of this wall material (due to the improvement of surface activity and emulsifying properties of protein as a result of partial enzymatic hydrolysis) to protect the antioxidant properties of GBLE during spray-drying, improving the production yield and preserving physical and functional characteristics of the encapsulated powders.

Ginkgo biloba supplement abates lead-induced endothelial and testicular dysfunction in Wistar rats via up-regulation of Bcl-2 protein expression, pituitary-testicular hormones and down-regulation of oxido-inflammatory reactions

BACKGROUND

Apoptotic and oxido-inflammatory pathways have been found to be up-regulated in lead acetate poisoning which has been associated to endothelial and testicular dysfunctions. It is yet uncertain, nevertheless, if treatment with Ginkgo biloba supplements (GBS), a flavonoid-rich natural product can lessen the adverse effects of lead on endothelial and testicular functions. This study investigated the impact of Ginkgo biloba supplementation on lead-induced endothelial and testicular dysfunctions.

METHODS

The animals were treated with GBS (50 mg/kg and 100 mg/kg orally) for 14 days following oral exposure to lead acetate (25 mg/kg) for 14 days. After euthanasia, blood samples, epididymal sperm, testes, and aorta were collected. The quantities of the hormones (testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH), as well as the anti-apoptotic, oxidative, nitrergic, inflammatory markers, were then determined using immunohistochemistry, ELISA, and conventional biochemical methods.

RESULTS

GBS reduced lead-induced oxidative stress by increasing the levels of the antioxidant enzymes catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD), while lowering malondialdehyde (MDA) in endothelium and testicular cells. Normal testicular weight was restored by GBS which also decreased endothelial endothelin-I and increased nitrite levels. TNF-α and IL-6 were decreased while Bcl-2 protein expression was enhanced. Lead-induced alterations in reproductive hormones (FSH, LH, and testosterone) were also restored to normal.

CONCLUSION

According to our result, using Ginkgo biloba supplement prevented lead from causing endothelial and testicular dysfunction by raising pituitary-testicular hormone levels, boosting Bcl-2 protein expression and lowering oxidative and inflammatory stress in the endothelium and testes.

Pharmacological activity of Aspalathus linearis extracts: pre-clinical research in view of prospective neuroprotection

OBJECTIVES

Rooibos tea, a very popular everyday beverage made of Aspalathus linearis plant material and containing multiple polyphenolic compounds, reveals an expectation to positively affect various processes observed in the pathogenesis of neurodegenerative diseases as in the case of consumption of other polyphenol-abundant food products.

METHODS

This review is based on available data from pre-clinical in vitro and in vivo studies and presents a broad report on the pharmacological activity of the A. linearis extracts relevant for neurodegenerative diseases.

RESULTS

Flavonoids present in herbal infusions are absorbed from gastro-intestinal tract and may affect the central nervous system. The experimental investigations yield the results indicating to supporting role of A. linearis in the prevention of neurodegeneration, primarily owing to anti-oxidative and anti-inflammatory properties, anti-hyperglycaemic and anti-hyperlipidaemic effects as well as favourable impact on neurotransmission with following cognitive and behavioural after-math.

DISCUSSION

The multiple pharmacological activities and safety of Aspalathus linearis extracts are commented in the manuscript. The continuous rooibos tea consumption seems to be safe (despite anecdotal liver irritation); however, there is a risk of herbal-drug interactions.

Differences in in vivo absorption of flavone glycosides, flavone aglycones and terpene lactones under different dosage forms and physiological conditions

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo biloba L. extract (GBE) oral preparations have been used for many years in the prevention and treatment of cardiovascular and cerebrovascular diseases, and the main active ingredients are flavonoids and terpene lactones. Among them, the oral absorption of the prototype components of flavonoid glycosides into the blood needs to be further clarified, and the differences in the oral absorption of different components in GBE by different dosage forms and physiological conditions are not clear yet.

AIM OF THE STUDY

To clarify the oral absorption of the prototype flavonoid glycosides in vivo, and to further explore the differences in the oral absorption of various active compounds under different oral dosage forms and dietary conditions.

MATERIALS AND METHODS

Firstly, the target compounds were selected based on the characteristic chromatogram of GBE and literature. Then, the content differences of three different oral GBE preparations were studied, and their pharmacokinetics (PK) were compared. Finally, the PK differences of the preparations with better oral absorption under different dietary conditions were studied.

RESULTS

Five flavonoid glycosides, three aglycones and four terpene lactones were selected as the research objects. The content determination results of GBE tablets, guttate pills and tinctures showed that the content of several components especially flavonoid glycosides in the tincture was higher than that of the other two preparations. After oral administration of these three preparations, the PK study showed different results from previous studies. The PK behavior of flavonoid glycosides was also determined at the same time as flavonoid glycosides and terpene lactones. and the bioavailability of flavonoid glycosides in the tincture was higher than that of the other two preparations. PK results of fasting and non-fasting showed that taking GBE tincture on an empty stomach increased the absorption of various compounds, especially flavonoid glycosides. However, due to the existence of food residues in the gastrointestinal tract, the oral bioavailability of flavonoid glycosides was significantly improved.

CONCLUSIONS

This study discussed the differences in the content and oral absorption of active compounds in different oral preparations of GBE, clarified the in vivo absorption of flavonoid glycosides prototype, as well as the influence of diet on the PK of active compounds, which has certain guiding significance for the clinical application of GBE oral preparations.

Vascular dementia subtypes, pathophysiology, genetics, neuroimaging, biomarkers, and treatment updates along with its association with Alzheimer's dementia and diabetes mellitus

Dementia is a chronic progressive cognitive decline illness that results in functional impairment. Vascular dementia (VaD), second only to Alzheimer's disease (AD), is one of the most prevalent forms of dementia in the elderly (aged over 65 years), with a varied presentation and unpredictable disease development caused by cerebrovascular or cardiovascular illness. To get a better understanding of the changes occurring in the brain and to drive therapy efforts, new biomarkers for early and precise diagnosis of AD and VaD are required. In this review, Firstly, we describe the subtypes of vascular dementia, their clinical features, pathogenesis, genetics implemented, and their associated neuroimaging and biomarkers, while describing extensively the recent biomarkers discovered in the literature. Secondly, we describe some of the well-documented and other less-defined risk factors and their association and pathophysiology in relation to vascular dementia. Finally, we follow recent updates in the management of vascular dementia along with its association and differentiation from Alzheimer's disease. The aim of this review is to gather the scattered updates and the most recent changes in blood, CSF, and neuroimaging biomarkers related to the multiple subtypes of vascular dementia along with its association with Alzheimer's dementia and diabetes mellitus.

The Use of Herbal Medicine in the Treatment of Vitiligo: An Updated Review

Vitiligo is a chronic disease of unknown etiology that causes progressive cutaneous depigmentation. Current pharmacological treatments have limited success and present significant risks. Many efforts have been made in recent years to explore new anti-vitiligo therapeutic strategies, including herbal-based therapies. The objective of the present review is to provide an updated overview on the most frequently used medicinal plants in the treatment of vitiligo. A bibliographical search was carried out in scientific databases Pubmed, Scifinder, Scopus, Google Scholar, and Medline up to October 2021 using the descriptors vitiligo, herbal, medicinal plants, and alternative therapies. In our search, the highest number of published studies comprise plants commonly used in traditional herbal medicine, highlighting the usefulness of ethnopharmacology in the discovery of new therapeutic agents. The review outlines current understanding and provides an insight into the role of psoralens and khellin (photosensitizing agents obtained from plants such as Cullen corylifolium or Ammi visnaga). The paper also describes other traditional herbs such as Ginkgo biloba, Phlebodium aureum, Piper nigrum, Picrorhiza kurroa, and Baccharoides anthelmintica that can likewise act as potential therapeutical agents. Based on our findings, photosensitizing agents in combination with phototherapy, the association of oral Phebodium aureum with phototherapies as well as oral G. biloba in monotherapy showed greater scientific evidence as therapeutic options. The research results emphasize that further investigation in this area is merited. More long-term follow up clinical trials and higher quality randomized trials are needed.

Multiplex quantitation of 17 drug-derived components in human plasma after administration of a fixed herbal preparation of Sailuotong using combined online SPE-LC-MS/MS methods

ETHNOPHARMACOLOGICAL RELEVANCE

Sailuotong (SLT) is a standardized herbal medicine formula made from extracts of ginseng (the dried root and rhizome of Panax ginseng C. A. Meyer), ginkgo (the leaves of Ginkgo biloba L.), and saffron (the stigma of Crocus sativus L.). It is prescribed compatibly for the treatment of vascular dementia (VaD) following the TCM principle of Qi-invigorating and Blood-activating. Ginseng is widely used as a tonic for the restoration of strength in China. Ginkgo and saffron have been traditionally used for a long time as medicines with the main effect of promoting blood circulation and removing blood stasis.

AIM OF THE STUDY

SLT has been proven to be a promising medicine for VaD by existing pharmacological and clinical evidence. To understand how the formula herbs and their active ingredients cooperate to produce comprehensive effects, the present study aimed to establish a highly sensitive and accurate quantitative method to reveal the plasma exposure profile of SLT in humans.

MATERIAL AND METHODS

Multiplex quantitation of a total of 17 SLT-derived components in human plasma was fulfilled by using online SPE for sample extractions followed by LC-MS/MS determinations. Among them, 8 ginsenoside (Rg1, Re, F1, Rf, Rb1, Rb2, Rc and Rd) were determined in ESI+ mode, and ginkgo flavonoids of quercetin, kaempferol, isorhamnetin were in ESI- mode. Improved sensitivity was achieved through optimizing the condition of sample extraction and LC separation, as well as mass parameters. 4 ginkgolides, including ginkgolide A, B, C and bilobalide, and 2 crocins of crocin-1 and its metabolite crocetin, were analyzed concurrently in negative ion mode, and their stability was ensured by a series of protective solutions.

RESULTS

The lower limit of quantitation was achieved to be extremely sensitive at 0.078 ng/mL for all ginsenosides, 0.033 ‒ 0.2 ng/mL for ginkgo flavonoids, 0.75 or 1.5 ng/mL for ginkgolides and 3 ng/mL for crocins. The methods were fully validated to be accurate and precise, and applicability was demonstrated by the analysis of clinical samples from 2 healthy volunteers.

CONCLUSION

The developed methods should be useful in further detailed clinical pharmacokinetic research for clarifying the effect mechanism of SLT and formulating its rational therapeutic regimens.

Effects of Organic Elicitors on the Recycled Production of Ginkgolide B in Immobilized Cell Cultures of Ginkgo biloba

Ginkgo biloba is a medicinal plant used in complementary and alternative medicines. Ginkgo biloba extracts contain many compounds with medical functions, of which the most critical is ginkgolide B (GB). The major role that GB plays is to function as an antagonist to the platelet-activating factor, which is one of the causes of thrombosis and cardiovascular diseases. Currently, GB is obtained mainly through extraction and purification from the leaves of Ginkgo biloba; however, the yield of GB is low. Alternatively, the immobilized cultivation of ginkgo calluses with biomaterial scaffolds and the addition of organic elicitors to activate the cell defense mechanisms were found to stimulate increases in GB production. The aim of this study was to use Ginkgo biloba calluses for immobilized cultures with different elicitors to find a more suitable method of ginkgolide B production via a recycling process.

Ginkgo biloba extracts (GBE) protect human RPE cells from t-BHP-induced oxidative stress and necrosis by activating the Nrf2-mediated antioxidant defence

OBJECTIVES

Age-related macular degeneration (AMD) is a prevalent ocular disease. Dry AMD accounts for most cases of blindness associated with AMD but there are no treatments. Oxidative stress-induced damage to retinal pigment epithelial (RPE) cells is a major contributor to the pathogenesis of dry AMD. This study investigated the protective actions of Ginkgo biloba extracts (GBE) in human RPE cells subjected to tert-butyl hydroperoxide (t-BHP)-mediated oxidative stress.

METHODS

The human ARPE-19 cells were pre-treated with or without GBE before the exposure to t-BHP. Cell viability, cell death profile and lipid peroxidation were assessed. The findings were verified using human primary RPE cultures.

KEY FINDINGS

GBE pre-treatment prevented the increase in lipid peroxidation and necrosis/ferroptosis, and the concurrent viability decrease in RPE cells exposed to t-BHP. It enabled the pronounced activation of Nrf2 and its downstream genes. We found that ERK1/2 phosphorylation was increased to a similar extent by t-BHP and GBE.

CONCLUSION

This study revealed that GBE pre-treatment attenuates pro-oxidant stress and protects human RPE cells from oxidative injury by modulating ERK1/2-Nrf2 axis. These findings suggest that GBE has the potential to be developed as a agent that may be valuable in decreasing AMD progression.

Phytochemical Profiles and Biological Studies of Selected Botanical Dietary Supplements Used in the United States

Based on their current wide bioavailability, botanical dietary supplements have become an important component of the United States healthcare system, although most of these products have limited scientific evidence for their use. The most recent American Botanical Council Market Report estimated for 2020 a 17.3% increase in sales of these products when compared to 2019, for a total sales volume of $11,261 billion. The use of botanical dietary supplements products in the United States is guided by the Dietary Supplement Health and Education Act (DSHEA) from 1994, enacted by the U.S. Congress with the aim of providing more information to consumers and to facilitate access to a larger number of botanical dietary supplements available on the market than previously. Botanical dietary supplements may be formulated for and use only using crude plant samples (e.g., plant parts such as the bark, leaves, or roots) that can be processed by grinding into a dried powder. Plant parts can also be extracted with hot water to form an "herbal tea." Other preparations of botanical dietary supplements include capsules, essential oils, gummies, powders, tablets, and tinctures. Overall, botanical dietary supplements contain bioactive secondary metabolites with diverse chemotypes that typically are found at low concentration levels. These bioactive constituents usually occur in combination with inactive molecules that may induce synergy and potentiation of the effects observed when botanical dietary supplements are taken in their different forms. Most of the botanical dietary supplements available on the U.S. market have been used previously as herbal remedies or as part of traditional medicine systems from around the world. Their prior use in these systems also provides a certain level of assurance in regard to lower toxicity levels. This chapter will focus on the importance and diversity of the chemical features of bioactive secondary metabolites found in botanical dietary supplements that are responsible for their applications. Many of the active principles of botanical dietary substances are phenolics and isoprenoids, but glycosides and some alkaloids are also present. Biological studies on the active constituents of selected botanical dietary supplements will be discussed. Thus, the present chapter should be of interest for both members of the natural products scientific community, who may be performing development studies of the products available, as well as for healthcare professionals who are directly involved in the analysis of botanical interactions and evaluation of the suitability of botanical dietary supplements for human consumption.

Ginkgo biloba Administered Singly and Combined With Antioxidants in Tinnitus Patients

BACKGROUND AND OBJECTIVES

Tinnitus, or ear ringing, involves impulsive and spontaneous activity in the auditory neurons. Its prevalence is high in the elderly, but 10%-15% of adults suffer from tinnitus, affecting their quality of life. Therefore, this study aimed to evaluate the efficacy of Ginkgo biloba administered singly and in combination with antioxidants in tinnitus patients. Subjects and.

METHODS

Patients were randomly allocated to Placebo (T0, n=22), Treatment 1 (T1, n=24), and Treatment 2 (T2, n=23) groups. The patients were educated on the study's methodology and were instructed to visit at 0, 4, 8, 12, and 14 weeks. The placebo group received starch capsule supplements. Conversely, the treatment groups received Ginkgo biloba (60 mg twice a day) singly and in combination with antioxidants. We enrolled 69 patients aged 40-70 years (41 men, 28 women). The Tinnitus Handicap Index (THI), Visual Analogue Score (VAS), and Short Form 36 (SF-36) Health Scores were determined pre- and post-treatment at each visit.

RESULTS

Supplementation of Ginkgo biloba, along with antioxidants, provided marked improvement (p<0.05) in post-treatment THI and VAS scores in the T2 group compared to those in the T1 and T0 groups. The greatest (p<0.05) percent difference was observed in the pre- and post-treatment THI (-36%) and VAS scores (-22.6%) of T2 patients. Likewise, the SF-36 scores improved significantly (p<0.05) in the T2 group in varied parameters.

CONCLUSIONS

Ginkgo biloba, along with antioxidants, can be a promising therapy for tinnitus patients, providing marked improvement in THI, VAS, and SF-36 scores.

Tissue-Specific Profiling of Biflavonoids in Ginkgo (Ginkgo biloba L.)

Biflavonoids are flavonoid dimers that are much less studied than monomeric flavonoids. Their precise distribution among plants and their role in plants is still unknown. Here, we have developed a HPLC-DAD method that allows us to separate and simultaneously determine the five major biflavonoids (amentoflavone, bilobetin, ginkgetin, isoginkgetin, and sciadopitysin) in ginkgo (Ginkgo biloba L.). We performed tissue-specific profiling of biflavonoids in ten different plant parts: tree bark, twigs bark, twigs without bark, buds, leaf petioles, leaf blades, seed stalks, sarcotesta, nutshells, and kernels. We did not detect biflavonoids in plant parts not in direct contact with the environment (twigs without bark, nutshells, and kernels). We found the highest total biflavonoids content in leaves, where sciadopitysin was predominant. In contrast, in the bark, amentoflavone was the predominant biflavonoid, suggesting that more methylated biflavonoids accumulate in leaves and seeds. This is probably related to their biological function, which remains to be determined.

Cardiovascular Activity of Ginkgo biloba-An Insight from Healthy Subjects

Ginkgo biloba is the oldest living tree species in the world. Despite less than encouraging clinical results, extracts from its leaves are among the most used herbal preparations in the prevention and treatment of cardiovascular diseases. Most data on the efficacy of Ginkgo biloba on cardiovascular disease is from clinical studies, with few results from healthy subjects. This paper aims to provide a comprehensive review of the mechanisms underlying the known beneficial cardiovascular activities of Ginkgo biloba. It displays myocardial suppressant and vasorelaxant activities ex vivo, potentiating endothelial-dependent and -independent pathways. It improves perfusion in different vascular beds, namely ocular, cochlear, cutaneous, cerebral, and coronary. Although scarce, evidence suggests that Ginkgo biloba displays a heterogeneous effect on tissue perfusion which is dependent on the individual elimination pathways. It displays an acceptable safety profile, with most reported adverse reactions constituting rare occurrences. Collectively, Ginkgo biloba positively impacts cardiovascular physiology, improving hemodynamics and organ perfusion. In the future, better controlled clinical studies should be performed in order to identify the target populations who may benefit the most from pharmacotherapeutic interventions involving Ginkgo biloba.

Ginkgo biloba Supplement Reverses Lead (II) Acetate-Induced Haematological Imbalances, Hepatic and Renal Dysfunctions in Male Wistar Rat

Lead is a heavy metal abundant in nature that causes haematological imbalances, and hepatic and renal dysfunction, and this imbalance has been linked to oxidative stress. Several reports have shown that natural products are implicated in ameliorating metal poisonings. Ginkgo biloba is a flavonoid-rich natural herbal supplement with several pharmacological properties. The present study investigated effect of Ginkgo biloba supplement (GBS) on lead-induced toxicity. Animals were given a lead dose of 25 mg/kg for 14 days orally and then given Ginkgo biloba supplements of 50 mg/kg and 100 mg/kg orally for 14 days. Animals given GBS had significantly improved haematological and rheological parameters. GBS showed a protective impact in terms of improved kidney and liver histology, anti-oxidant enzyme activity (CAT, SOD, GSH, and MDA), organ function indices, and a lower rate of erythrocyte osmotic fragility. Conclusively, Ginkgo biloba supplementation attenuated lead toxicity by normalization of haematological imbalances, and hepatic and renal dysfunction as well as maintaining erythrocyte membrane integrity.

Effects of ginkgo leaf tablet on the pharmacokinetics of rosiglitazone in rats and its potential mechanism

CONTEXT

Ginkgo leaf tablet (GLT), a traditional Chinese herbal formula, is often combined with rosiglitazone (ROS) for type 2 diabetes mellitus treatment. However, the drug-drug interaction between GLT and ROS remains unknown.

OBJECTIVE

To investigate the effects of GLT on the pharmacokinetics of ROS and its potential mechanism.

MATERIALS AND METHODS

The pharmacokinetics of 10 mg/kg ROS with 100/200 mg/kg GLT as single-dose and 10-day multiple-dose administration were investigated in Sprague-Dawley rats. In vitro, the effects of GLT on the activity of CYP2C8 and CYP2C9 were determined in recombinant human yeast microsomes and rat liver microsomes with probe substrates.

RESULTS

The t_1/2 of ROS increased from 2.14 ± 0.38 (control) to 2.79 ± 0.37 (100 mg/kg) and 3.26 ± 1.08 h (200 mg/kg) in the single-dose GLT administration. The AUC_0-t (139.69 ± 45.46 vs. 84.58 ± 39.87 vs. 66.60 ± 15.90 h·μg/mL) and t_1/2 (2.75 ± 0.70 vs. 1.99 ± 0.44 vs. 1.68 ± 0.35 h) decreased significantly after multiple-dose GLT treatment. The IC₅₀ values of quercetin, kaempferol, and isorhamnetin, GLT main constituents, were 9.32, 7.67, and 11.90 μmol/L for CYP2C8, and 27.31, 7.57, and 4.59 μmol/L for CYP2C9. The multiple-dose GLT increased rat CYP2C8 activity by 44% and 88%, respectively.

DISCUSSION AND CONCLUSIONS

The metabolism of ROS is attenuated in the single dose of GLT by inhibiting CYP2C8 and CYP2C9 activity, and accelerated after the multiple-dose GLT treatment via inducing CYP2C8 activity in rats, indicating that the clinical dose of ROS should be adjusted when co-administrated with GLT.

Ginkgo biloba for tinnitus

BACKGROUND

Tinnitus is a symptom defined as the perception of sound in the absence of an external source. In England alone there are an estimated ¾ million general practice consultations every year where the primary complaint is tinnitus, equating to a major burden on healthcare services. Clinical management strategies include education and advice, relaxation therapy, tinnitus retraining therapy (TRT), cognitive behavioural therapy (CBT), sound enrichment using ear-level sound generators or hearing aids, and drug therapies to manage co-morbid symptoms such as insomnia, anxiety or depression.  OBJECTIVES: To assess the effects of Ginkgo biloba for tinnitus in adults and children.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; CENTRAL (2022, Issue 6); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 7 June 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting adults and children with acute or chronic subjective tinnitus. We included studies where the intervention involved Ginkgo biloba and this was compared to placebo, no intervention, or education and information. Concurrent use of other medication or other treatment was acceptable if used equally in each group. Where an additional intervention was used equally in both groups, we analysed this as a separate comparison. The review included all courses of Ginkgo biloba, regardless of dose regimens or formulations, and for any duration of treatment.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were tinnitus symptom severity measured as a global score on a multi-item tinnitus questionnaire and serious adverse effects (bleeding, seizures). Our secondary outcomes were tinnitus loudness (change in subjective perception), tinnitus intrusiveness, generalised depression, generalised anxiety, health-related quality of life and other adverse effects (gastrointestinal upset, headache, allergic reaction). We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

This review included 12 studies (with a total of  1915 participants). Eleven studies compared the effects of Ginkgo biloba with placebo and one study compared the effects of Ginkgo biloba with hearing aids to hearing aids alone. All included studies were parallel-group RCTs. In general, risk of bias was high or unclear due to selection bias and poor reporting of allocation concealment and blinding of participants, personnel and outcome assessments. Due to heterogeneity in the outcomes measured and measurement methods used, only limited data pooling was possible.  Ginkgo biloba versus placebo When we pooled data from two studies for the primary outcome tinnitus symptom severity, we found that Ginkgo biloba may have little to no effect (Tinnitus Handicap Inventory scores) at three to six months compared to placebo, but the evidence is very uncertain (mean difference (MD) -1.35 (scale 0 to 100), 95% confidence interval (CI) -8.26 to 5.55; 2 studies; 85 participants) (very low-certainty). Ginkgo biloba may result in little to no difference in the risk of bleeding or seizures, with no serious adverse effects reported in either group (4 studies; 1154 participants; low-certainty). For the secondary outcomes, one study found that there may be little to no difference between the effects of Ginkgo biloba and placebo on tinnitus loudness measured with audiometric loudness matching at 12 weeks, but the evidence is very uncertain (MD -4.00 (scale -10 to 140 dB), 95% CI -13.33 to 5.33; 1 study; 73 participants) (very low-certainty). One study found that there may be little to no difference between the effects of Ginkgo biloba and placebo on health-related quality of life measured with the Glasgow Health Status Inventory at three months (MD -0.58 (scale 0 to 100), 95% CI -4.67 to 3.51; 1 study; 60 participants) (low-certainty). Ginkgo biloba may not increase the frequency of other adverse effects (gastrointestinal upset, headache, allergic reaction) at three months compared to placebo (risk ratio 0.91, 95% CI 0.52 to 1.60; 4 studies; 1175 participants) (low-certainty). None of the studies reported the other secondary outcomes of tinnitus intrusiveness or changes in depressive symptoms or depression, anxiety symptoms or generalised anxiety. Gingko biloba with concurrent intervention versus concurrent intervention only One study compared Ginkgo biloba with hearing aids to hearing aids only. It assessed the mean difference in the change in Tinnitus Handicap Inventory scores and tinnitus loudness using a 10-point visual analogue scale (VAS) at three months. The study did not report adverse effects, tinnitus intrusiveness, changes in depressive symptoms or depression, anxiety symptoms or generalised anxiety, or health-related quality of life. This was a single, very small study (22 participants) and for all outcomes the certainty of the evidence was very low. We were unable to draw meaningful conclusions from the numerical results.

AUTHORS' CONCLUSIONS

There is uncertainty about the benefits and harms of Ginkgo biloba for the treatment of tinnitus when compared to placebo. We were unable to draw meaningful conclusions regarding the benefits and harms of Ginkgo biloba when used with concurrent intervention (hearing aids). The certainty of the evidence for the reported outcomes, assessed using GRADE, ranged from low to very low. Future research into the effectiveness of Ginkgo biloba in patients with tinnitus should use rigorous methodology. Randomisation and blinding should be of the highest quality, given the subjective nature of tinnitus and the strong likelihood of a placebo response. The CONSORT statement should be used in the design and reporting of future studies. We also recommend the use of validated, patient-centred outcome measures for research in the field of tinnitus.

Leaves, seeds and exocarp of Ginkgo biloba L. (Ginkgoaceae): A Comprehensive Review of Traditional Uses, phytochemistry, pharmacology, resource utilization and toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo biloba L. (Ginkgoaceae) is a treasure species with high medicinal value. The Ming Dynasty "Compendium of Materia Medica" and Qing Dynasty "Bencao Fengyuan" in China recorded this herbal medicine can reduce phlegm, clear poison, treat diarrhea and frequent urination, etc. AIM OF THE STUDY: Until now, there is no painstakingly summarized review on leaves, seeds and exocarp of G. biloba simultaneously. This review will systematically summarize and compare current knowledge of G. biloba.

MATERIALS AND METHODS

Ample original publications related to traditional uses, phytochemistry, pharmacology, resource utilization and toxicity of G. biloba leaves, seeds and exocarp till the end of 2021 were searched and collected by using various literature databases, including China National Knowledge Infrastructure, PubMed, Elsevier, Springer, Google Scholar and Web of Science database.

RESULTS

According to classical Chinese herbal books and Chinese Pharmacopoeia, relieving cough, reducing phlegm, clearing poison and relieving diarrhea are the main pharmacological effects of G. biloba. The common chemical ingredients in different parts of G. biloba are flavonoids, terpenoids, phenolic acids, polysaccharides and endotoxin, etc. Among them, flavonoids and terpenoids are the main bioactive compounds in G. biloba leaves. Phenolic acids are the main bioactive compounds in G. biloba exocarp. G. biloba seeds are rich in nutritional ingredients, such as starch, adipose, protein, etc. Modern pharmacological studies showed that the crude extracts or compounds of G. biloba leaves, seeds and exocarp can be used for treating cardiovascular and cerebrovascular diseases, Alzheimer's disease, atherosclerosis, cancer, asthma, non-alcoholic fatty liver, diabetic complications and other diseases. In daily life, G. biloba seeds were usually used as raw material or additives for commodities, healthy food, drinks, even insecticides and antibacterial agents, etc. G. biloba leaves and seeds have been mainly applied for treating cardiovascular and cerebrovascular diseases, cough and asthma in clinical. However, endotoxins and ginkgolic acids have been identified as the dominating toxic ingredients in different parts of G. biloba. Besides, flavonoids and ginkgolides also have been proved to have toxicity recently.

CONCLUSIONS

This review systematically sums up and compares the traditional uses, phytochemistry, pharmacology, resource utilization and toxicity research progress of G. biloba leaves, seeds and exocarp for the first time. It will provide some comprehensive reference data and suggestions for future research on this herbal medicine.

Efficacy of Diterpene Ginkgolides Meglumine injection in elderly patients with ischemic stroke: A post hoc analysis of a randomized controlled trial

BACKGROUND

Elderly patients with ischemic stroke (IS) have worse functional outcomes and poorer quality of life after suffering a stroke than younger patients. The identification of effective agents is critical to optimizing the therapy of IS in elderly patients.

PURPOSE

To examine the efficacy of diterpene ginkgolides meglumine injection (DGMI) vs. Ginaton in treating patients with IS, across different age subgroups.

METHODS

Efficacy was determined through the post hoc analysis of a randomized controlled study, which had a cohort of 998 patients with IS. Participants were pooled and grouped by age (elderly [aged ≥ 65 yr] vs. non-elderly [aged < 65 yr]). The primary efficacy outcome was the proportion of patients with modified Rankin Scale (mRS) score ranging from 0 to 1 at 90 d. The secondary outcomes were neurological deficit (tested using the National Institutes of Health Stroke Scale [NIHSS] score) and quality of life (tested using the EuroQol-5 Dimension [EQ-5D] and EQ visual analog scale [EQ-VAS] questionnaires).

RESULTS

There were 399 (40%) patients in the elderly group (average age = 69.8±3.3 yr) and 599 (60%) patients in the non-elderly group (average age = 55.8±6.8 yr). The randomized treatment groups had similar baseline characteristics. For the elderly group, 174 (94%) of the 185 participants in the DGMI group and 169 (79%) of the 214 participants in the Ginaton group achieved the main outcome of a mRS score of 0-1 after three months (odds ratio [OR] = 0.87 [95% confidence interval [CI] = 0.81-0.93], p<0.001). For the non-elderly group, 301 (96%) of the 314 participants in the DGMI group and 237 (83%) of the 214 participants in the Ginaton group achieved the main outcome of a mRS score of 0-1 after three months (OR = 0.88 [95% CI = 0.84-0.92], p<0.001). The overall mean EQ-5D index score and EQ-VAS of the DGMI group were higher than that of the Ginaton group for elderly patients. After controlling other covariates including treatments, gender, weight, height and medical history, the results of mRS score, NIHSS score, EQ-5D index score, and EQ-VAS based on generalized linear model were similar to those of the single covariate analysis.

CONCLUSIONS

DGMI demonstrated a superior efficacy to Ginaton for patients with IS in both elderly and non-elderly ages.

Ginkgo biloba L. extract prevents steroid-induced necrosis of the femoral head by rescuing apoptosis and dysfunction in vascular endothelial cells via the PI3K/AKT/eNOS pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo biloba L. extract (EGb) is one of the world's most extensively used herbal medicines. Due to the diverse pharmacological properties of EGb, it has been used in the treatment of neurological illnesses, as well as cardiovascular and cerebrovascular ailments. However, the effect and pharmacological mechanism of EGb on steroid-induced necrosis of the femoral head (SINFH) are still unclear.

AIM OF THE STUDY

SINFH remains a challenging problem in orthopedics. Previous investigations have shown that EGb has the potential to reduce the occurrence of SINFH. The goal was to determine the effect and mechanism of EGb in preventing SINFH by inhibiting apoptosis and improving vascular endothelial cells (VECs) functions.

MATERIALS AND METHODS

CCK-8, nitric oxide (NO) production and flow cytometry were used to determine the cell apoptosis and function. The scratch and angiogenesis tests assessed migration and tube formation. Western blot analysis detected the expressions of apoptosis-related proteins and PI3K/AKT/eNOS pathway-related proteins. Apoptosis and angiogenesis were also detected treated with the inhibitors. A mouse model of SINFH was established. Paraffin section was used to determine the necrotic pathology and apoptosis. Vessels in the femoral heads were assessed by immunofluorescence staining.

RESULTS

When stimulated by methylprednisolone (MPS), cell viability, NO generation and tube formation were decreased, the apoptotic rate increased. Simultaneously, MPS decreased the expression levels of p-PI3K, p-AKT, and p-eNOS. EGb increased the expression levels of these proteins, restrained apoptosis, and restored cell functions. The addition of the inhibitors decreased anti-apoptotic effect and angiogenesis. In addition, when compared to the model mice, there were fewer empty lacunae and normal trabecular arrangement after taking different doses of EGb. The protective effect was also confirmed by the vascular quantitative analysis in vivo.

CONCLUSION

This study established that EGb increased endothelial cell activity and inhibited apoptosis and function loss induced by MPS, elucidating the effect and molecular mechanism of EGb on early SINFH.

Potentialities of Ginkgo extract on toxicants, toxins, and radiation: a critical review

Exposure to toxins is a severe threat to human health and life in today's developing and industrialized world. Therefore, identifying a protective chemical could be valuable and fascinating in this case. The purpose of this article was to bring together thorough review of studies on Ginkgo biloba to aid in the creation of ways for delivering its phytoconstituents to treat toxicants and radiation. This review gathered and evaluated studies on the defensive impact of Ginkgo biloba extract (GBE) against toxicities caused by toxic chemical agents (such as lead, cadmium, and aluminum), natural toxins (for example, lipopolysaccharide-induced toxicity and damage, gossypol, latadenes, and lotaustralin), and radiation (for example, gamma, ultra-violet, and radio-frequency radiation). According to this review, GBE has a considerable therapeutic effect by influencing specific pathophysiological targets. Furthermore, GBE has antioxidant, anti-inflammatory, anti-apoptotic, and antigenotoxicity properties against various toxicities. These are due to flavone glycosides (primarily isorhamnetin, kaempferol, and quercetin) and terpene trilactones (ginkgolides A, B, C, and bilobalide) that aid GBEs' neutralizing effect against radiation and toxins by acting independently or synergistically. This will serve as a reference for the functional food, cosmetic, and pharmaceutical industries worldwide.

Current Progress on Neuroprotection Induced by Artemisia, Ginseng, Astragalus, and Ginkgo Traditional Chinese Medicines for the Therapy of Alzheimer's Disease

Aging is associated with the occurrence of diverse degenerative changes in various tissues and organs and with an increased incidence of neurological disorders, especially neurodegenerative diseases such as Alzheimer's disease (AD). In recent years, the search for effective components derived from medicinal plants in delaying aging and preventing and treating neurodegenerative diseases has been increasing and the number of related publications shows a rising trend. Here, we present a concise, updated review on the preclinical and clinical research progress in the assessment of the therapeutic potential of different traditional Chinese medicines and derived active ingredients and their effect on the signaling pathways involved in AD neuroprotection. Recognized by their multitargeting ability, these natural compounds hold great potential in developing novel drugs for AD.

Potential natural products for the management of autism spectrum disorder

Autism in a broader sense is a neurodevelopmental disorder, which frequently occurs during early childhood and can last for a lifetime. This condition is primarily defined by difficulties with social engagement, with individuals displaying repetitive and stereotyped behaviors. Numerous neuroanatomical investigations on autistic children have revealed that their brains grow atypically, resulting in atypical neurogenesis, neuronal migration, maturation, differentiation, and degeneration. Special education programs, speech therapy, and occupational therapy have all been used to address autism-related behavioral problems. While widely prescribed antidepressant drugs, antipsychotics, anticonvulsants, and stimulants have demonstrated response in autistic individuals. However, these medications do not fully reverse the core symptoms associated with autism spectrum disorder (ASD). The adverse reactions of ASD medicines and an increased risk of developing various other problems, such as obesity, dyslipidemia, diabetes mellitus, and thyroid disorders, prompted the researchers to investigate herbal medicines for the treatment of autistic individuals. Clinical trials are now being done to establish the efficacy of alternative techniques based on natural substances and to understand better the context in which they may be used to treat autism. This review of literature will look at crucial natural compounds derived from animals and plants that have shown promise as safe and effective autism treatment strategies.

Ginkgolic acid improves bleomycin-induced pulmonary fibrosis by inhibiting SMAD4 SUMOylation

Idiopathic pulmonary fibrosis (IPF) is a refractory chronic respiratory disease with progressively exacerbating symptoms and a high mortality rate. There are currently only two effective drugs for IPF; thus, there is an urgent need to develop new therapeutics. Previous experiments have shown that ginkgolic acid (GA), as a SUMO-1 inhibitor, exerted an inhibitory effect on cardiac fibrosis induced by myocardial infarction. Regarding the pathogenesis of PF, previous studies have concluded that small ubiquitin-like modifier (SUMO) polypeptides bind multiple target proteins and participate in fibrosis of multiple organs, including PF. In this study, we found altered expression of SUMO family members in lung tissues from IPF patients. GA mediated the reduced expression of SUMO1/2/3 and the overexpression of SENP1 in a PF mouse model, which improved PF phenotypes. At the same time, the protective effect of GA on PF was also confirmed in the SENP1-KO transgenic mice model. Subsequent experiments showed that SUMOylation of SMAD4 was involved in PF. It was inhibited by TGF-β1, but GA could reverse the effects of TGF-β1. SENP1 also inhibited the SUMOylation of SMAD4 and then participated in epithelial-mesenchymal transition (EMT) downstream of TGF-β1. We also found that SENP1 regulation of SMAD4 SUMOylation affected reactive oxygen species (ROS) production during TGF-β1-induced EMT and that GA prevented this oxidative stress through SENP1. Therefore, GA may inhibit the SUMOylation of SMAD4 through SENP1 and participate in TGF-β1-mediated pulmonary EMT, all of which reduce the degree of PF. This study provided potential novel targets and a new alternative for the future clinical testing in PF.

Ginkgo biloba protects striatal neurodegeneration and gut phagoinflammatory damage in rotenone-induced mice model of Parkinson's disease: Role of executioner caspase-3/Nrf2/ARE signaling

Asymptomatic and early clinical stages of Parkinson's disease (PD) have been linked with comorbid non-motor symptoms including dysfunction of the gastrointestinal (GI) tract. Notwithstanding, neuroprotective and gastroprotective effects of Ginkgo biloba supplements (GBS) have been investigated independently. Hence, whether GBS-mediated GIT-protective capacity could be helpful in PD via gut-brain anti-inflammatory signaling still remains unknown. Treatment with GBS significantly repressed the motor behavioral and neuromuscular deficits and prevented loss of striatal dopaminergic loss by improving the level of tyrosine hydroxylase enzyme and suppressing synucleinopathy development. Striatal neurons and ileal epithelial injury following intraperitoneal rotenone administration were accompanied with oxidoinflammatory/nitroinflammatory stress and marked inhibition of cholinergic transmission. Moreover, there was increased striatal executioner caspase-3 and decreased nuclear factor erythroid-2-related factor 2 (Nrf2) immunoexpression, loss of striatal pyramidal neuron with a marked decrease in length and width of the dendritic spines as well as significant hyperplasia of cryptal cells in the ileal epithelial tissues, all which were reversed by the pretreatment + concurrent (Pre-CONC) and concurrent (CONC) GBS treatment pattern. In sum, we proved the potential dual effects of GBS in preventing both dopaminergic neural-related impairments and gut wall abnormalities linked with PD.

Benefits of Treatment with Ginkgo Biloba Extract EGb 761 Alone or Combined with Acetylcholinesterase Inhibitors in Vascular Dementia

BACKGROUND

Vascular dementia (VaD) is the most severe manifestation of cognitive impairment caused by cerebrovascular disease. There are currently no specific drug treatments approved for VaD, with cholinesterase inhibitors (AChEI) being frequently used in VaD. However, the benefits they provide are small and short-lived. The standardized extract of Ginkgo biloba EGb 761 has demonstrated protective properties against neuronal and vascular damage and has been used as a pharmacological treatment for VaD.

OBJECTIVES

This study aims to study the efficacy of EGb 761 alone and in combination with AChEI in a real-life setting. We carried out a retrospective analysis of data over a 12-month period in a sample of people suffering from VaD.

METHODS

We retrospectively identified 77 patients with a diagnosis of VaD who had received treatment with any of the following drugs: Ginkgo biloba extract EGb 761 (240 mg daily), donepezil (10 mg daily), galantamine (16 or 24 mg daily), or rivastigmine patch (9.5 or 13.3 mg daily). Subjects were divided into three groups according to the treatment they had received: EGb 761 alone (n = 25), AChEI alone (n = 26), and EGb 761+AChEI (n = 26). Cognitive functioning was assessed by Mini-Mental State Examination (MMSE), Rey Auditory Verbal Learning Test (RAVLT), Symbol Digit Modalities Test (SDMT), Boston Naming Test (BNT), Trail Making Test forms A (TMTA) and B (TMTB), Letter (LFT) and Category Fluency Test (CFT); neuropsychiatric symptoms were assessed by the Neuropsychiatric Inventory (NPI); functional capacity was assessed by Interview for Deterioration in Daily Living (IDDD).

RESULTS

A statistically significant improvement was observed in the EGb 761 group versus the AChEI group at 12 months' follow-up in CFT (+1.74, p < 0.001), TMTA (-17.91, p = 0.031) and NPI (-5.89, p < 0.001). With regard to the combined treatment, a statistically significant improvement was shown in the EGb 761 plus AChEI treatment group versus AChEI group at the 12-month follow-up in MMSE (+2.0, p = 0.001), RAVLT (+2.23, p = 0.007), CFT (+1.15, p = 0.013), TMTA (-19.92, p = 0.012), TMTB (-46.50, p < 0.001) and NPI (-6.77, p < 0.001). In the same line, a statistically significant improvement was observed in the EGb 761 plus AChEI treatment group versus EGb 761 at 12-month follow-up regarding MMSE (+2.11, p = 0.001), RAVLT (+2.35, p = 0.004) and TMTB (-25.25, p = 0.015).

CONCLUSION

After 12 months of treatment EGb 761 alone or combined with AChEI showed cognitive and behavioral benefits in patients suffering from VaD. This study thus provides additional real-world evidence for the combined use of EGb 761 and anti-dementia drugs in VaD patients.

Gingko biloba abrogate lead-induced neurodegeneration in mice hippocampus: involvement of NF-κB expression, myeloperoxidase activity and pro-inflammatory mediators

Neuroimmune alterations have important implication in the neuropsychiatric symptoms and biochemical changes associated with lead-induced neurotoxicity. It has been suggested that inhibition of neuroinflammatory-mediated lead-induced neurotoxicity by phytochemicals enriched with antioxidant activities would attenuate the deleterious effects caused by lead. Hence, this study investigated the neuroinflammatory mechanism behind the effect of Ginkgo biloba supplement (GB-S) in lead-induced neurotoxicity in mice brains. Mice were intraperitoneally pretreated with lead acetate (100 mg/kg) for 30 min prior the administration of GB-S (10 and 20 mg/kg, i.p.) and ethylenediaminetetraacetic acid (EDTA) (50 mg/kg, i.p.) for 14 consecutive days. Symptoms of neurobehavioral impairment were evaluated using open field test (OFT), elevated plus maze (EPM), and tail suspension test (TST) respectively. Thereafter, mice brain hippocampi were sectioned for myeloperoxidase activity (MPO), pro-inflammatory cytokine (TNF-α and IL-6) estimation and inflammatory protein (NF-κB) expression. Furthermore, histomorphormetric studies (Golgi impregnation and Cresyl violet stainings) were carried out. GB-S (10 and 20 mg/kg) significantly restores neurobehavioral impairments based on improved locomotion, reduced anxiety- and depressive-like behavior. Moreover, GB-S reduced the MPO activity, inhibits TNF-α, IL-6 release, and downregulates NF-κB immunopositive cell expression in mice hippocampus. Histomorphometrically, GB-S also prevents the loss of pyramidal neuron in the hippocampus. The endpoint of this findings suggest that GB-S decreases neuropsychiatric symptoms induced by lead acetate through mechanisms related to inhibition of release of pro-inflammatory mediators and suppression of hippocampal pyramidal neuron degeneration in mice.

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.

Ginkgo Biloba: A Famous Living Fossil Tree and an Ancient Herbal Traditional Chinese Medicine

Background:

Ginkgo (Ginkgo biloba) is a living fossil and a deciduous tree, having extracts with antidiabetic, antioxidant, anticancer, antihypertensive, immunostimulating, hepatoprotective, and antimicrobial activities, memory enhancement efficiency, and beneficial effects against neurodegenerative disease.

Objective:

This study aimed at evaluating the medicinal values and natural benefits of Ginkgo.

Methods:

This review investigated publication in MEDLINE/PubMed database and Google Scholar. The keywords used for an electronic search were Ginkgo biloba, living fossil, bioactive components, and traditional Chinese medicine.

Results:

The main active constituents of Ginkgo biloba are flavone glycosides such as kaempferol, quercetin, and isorhamnetin, terpene lactones, alkylphenols, proanthocyanidins, rhamnose, glucose, D-glucaric acid, ginkgolic acid, organic acids such as hydroxykinurenic, kynurenic, protocatechic, shikimic, and vanillic. Ginkgo kernels have been used as medicine or eaten as nuts in traditional medicinal science. The most notable pharmaceutical applications of Ginkgo are observed in cardiovascular disease, Alzheimer's disease, impaired cerebral performance, vascular insufficiency, antidepressant-induced sexual dysfunction, premenstrual syndrome, liver fibrosis, vascular disease, tinnitus, macular degeneration, memory, and vertigo.

Conclusion:

The development of modern drugs from Ginkgo by considering the importance of traditional medicinal Asian science with further research works should be emphasized.

The Optimization of Extraction Process, Antioxidant, Whitening and Antibacterial Effects of Fengdan Peony Flavonoids

Flavonoids have important biological activities, such as anti-inflammatory, antibacterial, antioxidant and whitening, which is a potential functional food raw material. However, the biological activity of Fengdan peony flavonoid is not particularly clear. Therefore, in this study, the peony flavonoid was extracted from Fengdan peony seed meal, and the antioxidant, antibacterial and whitening activities of the peony flavonoid were explored. The optimal extraction conditions were methanol concentration of 90%, solid-to-liquid ratio of 1:35 g:mL, temperature of 55 °C and time of 80 min; under these conditions, the yield of Fengdan peony flavonoid could reach 1.205 ± 0.019% (the ratio of the dry mass of rutin to the dry mass of peony seed meal). The clearance of Fengdan peony total flavonoids to 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, hydroxyl radical and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical could reach 75%, 70% and 97%, respectively. Fengdan peony flavonoid could inhibit the growth of the Gram-positive bacteria. The minimal inhibitory concentrations (MICs) of Fengdan peony flavonoid on S. aureus, B. anthracis, B. subtilis and C. perfringens were 0.0293 mg/mL, 0.1172 mg/mL, 0.2344 mg/mL and 7.500 mg/mL, respectively. The inhibition rate of Fengdan peony flavonoid on tyrosinase was 8.53-81.08%. This study intensely illustrated that the antioxidant, whitening and antibacterial activity of Fengdan peony total flavonoids were significant. Fengdan peony total flavonoids have a great possibility of being used as functional food materials.

Efficacy and safety of standardized Ginkgo biloba L. leaves extract as an adjuvant therapy for sudden sensorineural hearing loss: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo biloba L. has been used for medical purposes in China for centuries. Standardized Ginkgo biloba L. leaves extract (GBE) is a widely used botanical drug which displays a variety of pharmacological effects against sudden sensorineural hearing loss (SSNHL).

AIM OF THE STUDY

To evaluate the efficacy and safety of GBE as an adjuvant therapy, administered with corticosteroids, for the initial management of patients with SSNHL.

MATERIALS AND METHODS

We searched seven databases for randomized clinical trials (RCTs) comparing GBE plus corticosteroids with corticosteroids alone for SSNHL treatment. Data analysis was carried out by Review Manager 5.4 and Stata 16.0 software. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. We subsequently evaluated the certainty of evidence using the GRADE (Grading of Recommendation Assessment, Development and Evaluation) approach.

RESULTS

A total of 11 RCTs involving 1069 patients were included. Meta-analysis indicated that the clinical cure rate (RR = 1.33, 95% CI = 1.12 to 1.58, P = 0.001) and total effective rate (RR = 1.24, 95%CI = 1.17 to 1.31, P < 0.001) in SSNHL patients receiving GBE plus corticosteroids was superior to patients receiving corticosteroids alone. After treatment, pure tone average (PTA) improvement of observation group was better than that in the control group (WMD = 10.33, 95%CI = 6.46 to 14.21, P < 0.001). The levels of whole blood high shear viscosity (WMD = 0.93, 95%CI = 0.28 to 1.59, P = 0.005), whole blood medium shear viscosity (WMD = 0.53, 95%CI = 0.11 to 0.95, P = 0.01), whole blood low shear viscosity (WMD = 1.26, 95%CI = 0.80 to 1.72, P < 0.001), plasma viscosity (WMD = 0.19, 95%CI = 0.09 to 0.30, P < 0.001) and fibrinogen (WMD = 0.80, 95%CI = 0.25 to 1.35, P = 0.004) were lower than those in the control group. There was no significant difference in the change of hematokrit between two groups (WMD = 4.23, 95%CI = -0.54 to 8.99, P = 0.08). GBE was generally well tolerated, and there was no significant difference in the incidence of adverse reactions between two groups (RR = 1.01, 95%CI = 0.57 to 1.79, P = 0.97).

CONCLUSION

The results of the current study suggested that GBE might be effective and promising as an adjuvant to corticosteroids in the initial treatment of moderate to profound SSNHL. However, the GRADE assessment indicated that the overall strength of evidence was not high. Further studies with high methodological quality and low risk of bias are needed to confirm the positive results. PROSPERO registration No. CRD 42020190113.

Target profiling of flavonol glycosides in the extract of Ginkgo biloba leaf and their pharmacokinetics in rat plasma by ultra-high-performance liquid chromatography with tandem mass spectrometry

The extract of Ginkgo biloba leaf is a popular herbal product or dietary supplement in the world to treat various diseases, and flavonol glycosides are considered as the main bioactive constituents. In this study, 37 flavonol glycosides were rapidly screened out by precursor ion scanning in positive ion mode with production ions at m/z 287.05, 303.05, and 317.06. Subsequently, a reliable and sensitive ultra-high-performance liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry approach was established and validated to quantify the 20 prototype flavonol glycosides in rat plasma. Calibration curves showed good linearity (R² ≥ 0.9894) over the corresponding concentration range. The precision, accuracy, extraction recovery, matrix effect, and stability were also satisfactory. The validated method was successfully applied to a pharmacokinetic study of prototype flavonol glycosides in rat after oral administration of the extract of G. biloba leaf. As a result, the T_max of flavonol glycosides was short at 0.11-0.60 h. Quercetin-3-O-(2",6″-di-O-rhamnosyl)-glucoside, kaempferol-3-O-(2'',6''-di-O-rhamnosyl)-glucoside, quercetin-3-O-rutinoside, quercetin- 3-O-glucosyl-(1-2)-O-rhamnoside, and kaempferol-3-O-glucoside presented relatively high systemic exposure levels with AUC_0-∞  > 500 μg h/L and C_max  > 100 μg/L. This study would provide the valuable information for further scientific research and clinical application of the extract of G. biloba leaf.