Neuroprotective effects of Ginkgo biloba extract and Ginkgolide B against oxygen-glucose deprivation/reoxygenation and glucose injury in a new in vitro multicellular network model

Natural herbal extract roles and mechanisms in treating cerebral ischemia: A systematic review

Background

Stroke has been the focus of medical research due to its serious consequences and sequelae. Among the tens of millions of new stroke patients every year, cerebral ischemia patients account for the vast majority. While cerebral ischemia drug research and development is still ongoing, most drugs are terminated at preclinical stages due to their unacceptable toxic side effects. In recent years, natural herbs have received considerable attention in the pharmaceutical research and development field due to their low toxicity levels. Numerous studies have shown that natural herbs exert actions that cannot be ignored when treating cerebral ischemia.

Methods

We reviewed and summarized the therapeutic effects and mechanisms of different natural herbal extracts on cerebral ischemia to promote their application in this field. We used keywords such as "natural herbal extract," "herbal medicine," "Chinese herbal medicine" and "cerebral ischemia" to comprehensively search PubMed, ScienceDirect, ScienceNet, CNKI, and Wanfang databases, after which we conducted a detailed screening and review strategy.

Results

We included 120 high-quality studies up to 10 January 2024. Natural herbal extracts had significant roles in cerebral ischemia treatments via several molecular mechanisms, such as improving regional blood flow disorders, protecting the blood-brain barrier, and inhibiting neuronal apoptosis, oxidative stress and inflammatory responses.

Conclusion

Natural herbal extracts are represented by low toxicity and high curative effects, and will become indispensable therapeutic options in the cerebral ischemia treatment field.

An Update on the Application of Nano Phytomedicine as an Emerging Therapeutic Tool for Neurodegenerative Diseases

Abstract:

The existence of the blood-brain barrier (BBB), a densely woven network of blood vessels and endothelial cells designed to prevent the infiltration of foreign substances into the brain, the methods employed in developing treatments for neurodegenerative disorders (NDs) such as Alzheimer's disease, Parkinson's disease, Huntington's disease, Multiple sclerosis, Amyotrophic lateral sclerosis, and others, pose significant challenges and complexities. These illnesses have had a terrible impact on the human population's health. Because early detection of these problems is poor and no good therapy has been established, they have emerged as the biggest lifethreatening healthcare burden worldwide compared to other significant illnesses. Traditional drug delivery techniques do not offer efficient treatment for NDs due to constraints in the BBB design, efflux pumps, and metabolic enzyme expression. Nanotechnology has the potential to significantly enhance ND therapy by utilizing systems that have been bioengineered to engage with living organisms at the cellular range. Compared to traditional techniques, nanotechnological technologies have several potential ways for crossing the BBB and increasing therapeutic efficacy in the brain. The introduction and growth of nanotechnology indicate promising potential for overcoming this issue. Engineered nanoparticles coupled with therapeutic moieties and imaging agents with dimensions ranging from 1-100 nm can improve effectiveness, cellular uptake, selective transport, and drug delivery to the brain due to their changed physicochemical properties. Conjugates of nanoparticles and medicinal plants, or their constituents known as nano phytomedicine, have recently gained importance in developing cutting-edge neuro-therapeutics due to their abundant natural supply, promising targeted delivery to the brain, and lower potential for adverse effects. This study summarizes the common NDs, their prevalence and pathogenesis, and potential herbal nanoformulation for treating NDs.

Therapeutic Polymer-Based Cannabidiol Formulation: Tackling Neuroinflammation Associated with Ischemic Events in the Brain

Cannabidiol (CBD) is the most relevant nonpsychostimulant phytocompound found in Cannabis sativa. CBD has been extensively studied and has been proposed as a therapeutic candidate for neuroinflammation-related conditions. However, being a highly lipophilic drug, it has several drawbacks for pharmaceutical use, including low solubility and high permeability. Synthetic polymers can be used as drug delivery systems to improve CBD's stability, half-life, and biodistribution. Here, we propose using a synthetic polymer as a nanoparticulate vehicle for CBD (NPCBD) to overcome the pharmacological drawbacks of free drugs. We tested the NPCBD-engineered system in the context of ischemic events in a relevant oxygen and glucose deprivation (OGD) model in primary cortical cells (PCC). Moreover, we have characterized the inflammatory response of relevant cell types, such as THP-1 (human monocytes), HMC3 (human microglia), and PCC, to NPCBD and observed a shift in the inflammatory state of the treated cells after the ischemic event. In addition, NPCBD exhibited a promising ability to restore mitochondrial function after OGD insult in both HMC3 and PCC cells at low doses of 1 and 0.2 μM CBD. Taken together, these results suggest the potential for preclinical use.

Chinese herbal medicine Ginkgo biloba L. preparations for ischemic stroke: An overview of systematic reviews and meta-analyses

BACKGROUND

Ginkgo biloba L. preparations (GBLPs) are a class of Chinese herbal medicine used in the adjuvant treatment of ischemic stroke (IS). Recently, several systematic reviews (SRs) and meta-analyses (MAs) of GBLPs for IS have been published.

OBJECTIVE

This overview aims to assess the quality of related SRs and MAs.

SEARCH STRATEGY

PubMed, Embase, Cochrane Library, Web of Science, Chinese Biological Medicine, China National Knowledge Infrastructure, Wanfang, and Chinese Science and Technology Journals databases were searched from their inception to December 31, 2022.

INCLUSION CRITERIA

SRs and MAs of randomized controlled trials (RCTs) that explored the efficacy of GBLPs for patients with IS were included.

DATA EXTRACTION AND ANALYSIS

Two independent reviewers extracted data and assessed the methodological quality, risk of bias (ROB), reporting quality, and credibility of evidence of the included SRs and MAs using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), Risk of Bias in Systematic Reviews (ROBIS), the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), and the Grading of Recommendations Assessment, Development and Evaluation (GRADE), respectively. Additionally, descriptive analysis and data synthesis were conducted.

RESULTS

Twenty-nine SRs/MAs involving 119 outcomes were included in this review. The overall methodological quality of all SRs/MAs was critically low based on AMSTAR 2, and 28 had a high ROB based on the ROBIS. According to the PRISMA statement, the reporting items of the included SRs/MAs are relatively complete. The results based on GRADE showed that of the 119 outcomes, 8 were rated as moderate quality, 24 as low quality, and 87 as very low quality. Based on the data synthesis, GBLPs used in conjunction with conventional treatment were superior to conventional treatment alone for decreasing neurological function scores.

CONCLUSION

GBLPs can be considered a beneficial supplemental therapy for IS. However, because of the low quality of the existing evidence, high-quality RCTs and SRs/MAs are warranted to further evaluate the benefits of GBLPs for treating IS. Please cite this article as: Meng TT, You YP, Li M, Guo JB, Song XB, Ding JY, Xie XL, Li AQ, Li SJ, Yin XJ, Wang P, Wang Z, Wang BL, He QY. Chinese herbal medicine Ginkgo biloba L. preparations for ischemic stroke: An overview of systematic reviews and meta-analyses. J Integr Med. 2024;22(2): 163-179.

Anti-atherosclerotic effects and molecular targets of ginkgolide B from Ginkgo biloba

Bioactive compounds derived from herbal medicinal plants modulate various therapeutic targets and signaling pathways associated with cardiovascular diseases (CVDs), the world's primary cause of death. Ginkgo biloba , a well-known traditional Chinese medicine with notable cardiovascular actions, has been used as a cardio- and cerebrovascular therapeutic drug and nutraceutical in Asian countries for centuries. Preclinical studies have shown that ginkgolide B, a bioactive component in Ginkgo biloba , can ameliorate atherosclerosis in cultured vascular cells and disease models. Of clinical relevance, several clinical trials are ongoing or being completed to examine the efficacy and safety of ginkgolide B-related drug preparations in the prevention of cerebrovascular diseases, such as ischemia stroke. Here, we present a comprehensive review of the pharmacological activities, pharmacokinetic characteristics, and mechanisms of action of ginkgolide B in atherosclerosis prevention and therapy. We highlight new molecular targets of ginkgolide B, including nicotinamide adenine dinucleotide phosphate oxidases (NADPH oxidase), lectin-like oxidized LDL receptor-1 (LOX-1), sirtuin 1 (SIRT1), platelet-activating factor (PAF), proprotein convertase subtilisin/kexin type 9 (PCSK9) and others. Finally, we provide an overview and discussion of the therapeutic potential of ginkgolide B and highlight the future perspective of developing ginkgolide B as an effective therapeutic agent for treating atherosclerosis.

Suppressive effects of bilobalide on depression-like behaviors induced by chronic unpredictable mild stress in mice

Background: Depression is a psychiatric disorder with depressed mood and even suicide attempts as the main clinical symptoms, and its pathogenesis has not yet been fully elucidated. Brain derived neurotrophic factor (BDNF) plays an important role in the pathogenesis of depression. Purpose: The main aim of the present study was to evaluate the effectiveness and reveal the potential mechanisms of bilobalide (BB) intervention in alleviating depression-like behaviors by using chronic unpredictable mild stress (CUMS) mice via mediating the BDNF pathway. Methods: Behavioral assessments were carried out by using the sucrose preference test (SPT), tail suspension test (TST), and forced swimming test (FST). CUMS mice were randomly divided into 5 groups: CUMS + solvent, CUMS + BB low, CUMS + BB medium, CUMS + BB high and CUMS + fluoxetine. Total serum levels of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) were measured by ELISA. Expression of TNF-α, IL-6, AKT, GSK3β, β-catenin, Trk-B and BDNF in the mouse hippocampus was assessed by western blotting. Results: BB treatment reduced the levels of pro-inflammatory cytokines (IL-6 and TNF-α) and increased the protein expression of BDNF in the hippocampus region of the CUMS mice. Moreover, BB treatment enhanced the AKT/GSK3β/β-catenin signaling pathway which is downstream of the BDNF receptor Trk-B in the hippocampus of these mice. Conclusions: Overall, the experimental results indicated that BB reverses CUMS-induced depression-like behavior. BB exerts antidepressant-like effects by inhibiting neuroinflammation and enhancing the function of neurotrophic factors.

Recent advancements of nanoparticles application in cancer and neurodegenerative disorders: At a glance

Nanoscale engineering is one of the innovative approaches to heal multitudes of ailments, such as varieties of malignancies, neurological problems, and infectious illnesses. Therapeutics for neurodegenerative diseases (NDs) may be modified in aspect because of their ability to stimulate physiological response while limiting negative consequences by interfacing and activating possible targets. Nanomaterials have been extensively studied and employed for cancerous therapeutic strategies since nanomaterials potentially play a significant role in medical transportation. When compared to conventional drug delivery, nanocarriers drug delivery offers various benefits, such as excellent reliability, bioactivity, improved penetration and retention impact, as well as precise targeting and administering. Upregulation of drug efflux transporters, dysfunctional apoptotic mechanisms, and a hypoxic atmosphere are all elements that lead to cancer treatment sensitivity in humans. It has been possible to target these pathways using nanoparticles and increase the effectiveness of multidrug resistance treatments. As innovative strategies of tumor chemoresistance are uncovered, nanomaterials are being developed to target specific pathways of tumor resilience. Scientists have recently begun investigating the function of nanoparticles in immunotherapy, a field that is becoming increasingly useful in the care of malignancies. Nanoscale therapeutics have been explored in this scientific literature and represent the most current approaches to neurodegenerative illnesses and cancer therapy. In addition, current findings and various biomedical nanomaterials' future promise for tissue regeneration, prospective medication design, and the synthesis of novel delivery approaches have been emphasized.

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.

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.

A review of dementia, focusing on the distinct roles of viral protein corona and MMP9 in dementia: Potential pharmacotherapeutic priorities

Dementia, in particular, is a defining feature of Alzheimer's and Parkinson's diseases. Because of the combination of motor and cognitive impairments, Parkinson's disease dementia (PDD) has a greater impact on affected people than Alzheimer's disease dementia (ADD) and others. If one family member develops dementia, the other members will suffer greatly in terms of social and occupational functioning. Currently, no relevant treatment is available based on an examination of the absolute pathophysiology of dementia. As a result, our objective of current review encouraged to look for dementia pharmacotherapy based on their pathogenesis. We systematically searched electronic databases such as PubMed, Scopus, and ESCI for information on the pathophysiology of demetia, as well as their treatment with allopathic and herbal medications. By modulating intermediate proteins, oxidative stress, viral protein corona, and MMP9 are etiological factors that cause dementia. The pathophysiology of ADD was described by two hypotheses: the amyloid cascade hypothesis and the tau and tangle hypothesis. ADD is caused by an increase in amyloid-beta (Aβ) and neurofibrillary tangles in the cerebrum. The viral protein corona (VPC) is more contagious and helps to form amyloid-beta (Aβ) plaques and neurofibrillary tangles in the cerebrum. Thioredoxin interacting protein (TXNIP) inside the BBB encourages Aβ to become more engaged. PDD is caused by decreased or absent dopamine secretion from nerve cells in the substantia nigra, as well as PRKN gene deletion/duplication mutations, and shift in the PRKN-PACRG organisation, all of which are linked to ageing. This article discussed the pathophysiology of dementia, as well as a list of herbal medications that can easily cross the BBB and have a therapeutic effect on dementia.

Anxiety faintly and depression remarkably correlate with recurrence in acute ischemic stroke patients: A study with 3-year longitude evaluation and follow-up

Clinical value of anxiety and depression in acute ischemic stroke (AIS) is rarely studied. Thus, the aim of this study was to explore longitudinal changes of anxiety and depression, as well as their correlation with recurrence in AIS.A total of 120 AIS patients and 120 controls were enrolled in the study. Furthermore, comparison of the hospital anxiety and depression scale (HADS) score or rate between AIS and controls was determined by Mann-Whitney U test or Chi-square test. In AIS patients, change of HADS scores or linear trend of anxiety and depression rate over time were determined by Friedman test or Mantel-Haenszel Chi-square test. Moreover, correlation of anxiety and depression with the recurrence rate was analyzed by log-rank test.HADS for anxiety score, anxiety rate, HADS for depression score and depression rate were all elevated in AIS patients compared with controls (all P < .001). In AIS patients, HADS for anxiety score was elevated from discharged from hospital (M0) to month (M) 36 (P = .027), while anxiety rate was not (P = .107). Besides, HADS-D score and rate were both increased from M0 to M36 (both P < .001). Moreover, accumulating recurrence rate was 6.7%, 11.7%, and 17.5% at 1 year, 2 years, and 3 years, respectively. Additionally, anxiety at M24 (P = .033), depression at M0, M12, M24, and M36 (all P < .05) were all correlated with increased accumulating recurrence rate.Continuous monitoring of anxiety and depression might be beneficial for the management of AIS prognosis.

Ginkgolide With Intravenous Alteplase Thrombolysis in Acute Ischemic Stroke Improving Neurological Function: A Multicenter, Cluster-Randomized Trial (GIANT)

Background and Purpose: We aimed to investigate the effect of Ginkgolide® treatment on neurological function in patients receiving intravenous (IV) recombinant tissue plasminogen activator (rt-PA). Methods: This cluster randomized controlled trial included acute ischemic stroke patients in 24 centers randomized to intervention of intravenous Ginkgolide® or control group within the first 24 h after IV rt-PA therapy (IVT). Clinical outcome at 90 days was assessed with modified Rankin Scale (mRS) score and dichotomized into good outcome (0-2) and poor outcome (3-6). Hemorrhagic transformation represented the conversion of a bland infarction into an area of hemorrhage by computed tomography. Symptomatic intracerebral hemorrhage (sICH) was defined as cerebral hemorrhagic transformation in combination with clinical deterioration of National Institutes of Health Stroke Scale (NIHSS) score ≥4 points at 7-day or if the hemorrhage was likely to be the cause of the clinical deterioration. We performed logistic regression analysis and propensity score matching analysis to investigate the impact of Ginkgolide® treatment with IV rt-PA on good outcome, hemorrhagic transformation and sICH, respectively. Results: A total of 1113 patients were finally included and 513 (46.1%) were in the intervention group. Patients in the Ginkgolide® group were more likely to have good outcomes (78.6 vs. 66.7%, p < 0.01) and lower rate of sICH (0 vs. 2.72%, p < 0.01), compared with patients in the control group. The intra-cluster correlation coefficient (ICC) for good outcome at 90 days was 0.033. Binary logistic regression analysis revealed that treatment with Ginkgolide® was independently associated with 90-day mRS in patients with IV rt-PA therapy (OR 1.498; 95% CI 1.006-2.029, p = 0.009). After propensity score matching, conditional logistic regression showed intervention with Ginkgolide® was significantly associated with 90-day good outcome (OR 1.513; 95% CI 1.073-2.132, p = 0.018). No significant difference in hemorrhage transformation was seen between the 2 matched cohorts (OR 0.885; 95% CI 0.450-1.741, p = 0.724). Conclusion: Using Ginkgolide® within 24-hour after IV rt-PA is effective and safe and might be recommended in combination with rtPA therapy in acute ischemic stroke. Clinical Trial Registration: http://www.clinicaltrials.gov, identifier NCT03772847.

Anti-tumor effect of ginkgetin on human hepatocellular carcinoma cell lines by inducing cell cycle arrest and promoting cell apoptosis

This study explored the anti-tumor effect of ginkgetin, an extract from ginkgo biloba, on human hepatocellular carcinoma cell lines and the underlying mechanisms. Cell viability was measured by MTT assay. Apoptotic cell morphology was observed under an inverted microscope after Hoechst 33,258 staining, and the ratio of apoptotic and necrotic cells was examined by flow cytometry after FITC/PI staining. Cell cycle changes were analyzed using flow cytometry. Cytochrome c release and caspase 3 and 8 activities were monitored using the relevant reagent kits. The levels of cell cycle-related proteins were detected by Western blot. MTT results indicated that ginkgetin significantly reduced HepG2 cell viability in a dose-dependent manner. Cellular morphology observation revealed that ginkgetin induced typical apoptotic morphological features of HepG2 cells, such as increased apoptotic bodies and cell shrinkage. Cell cycle analysis showed that ginkgetin increased the proportion of cells in the S phase. S-phase cell accumulation could be attributed to the decreased expression of cell cycle regulatory factors. Similarly, ginkgetin also induced the apoptosis and S phase cell accumulation of another human HCC cell line SK-HEP-1. Furthermore, ginkgetin treatment increased caspase-3 activity and cytochrome c release but not caspase-8 activity, implying that ginkgetin might mediate cell apoptosis through the mitochondrial pathway. In addition, the tumor formation experiment in nude mice showed that ginkgetin administration inhibited tumor growth. These results suggest that ginkgetin could be a cell apoptosis stimulator by affecting the balance between cell proliferation and apoptosis, suggesting that ginkgetin might be suitable for human HCC treatment.

Nutrition, Physical Activity, and Other Lifestyle Factors in the Prevention of Cognitive Decline and Dementia

Multiple factors combined are currently recognized as contributors to cognitive decline. The main independent risk factor for cognitive impairment and dementia is advanced age followed by other determinants such as genetic, socioeconomic, and environmental factors, including nutrition and physical activity. In the next decades, a rise in dementia cases is expected due largely to the aging of the world population. There are no hitherto effective pharmaceutical therapies to treat age-associated cognitive impairment and dementia, which underscores the crucial role of prevention. A relationship among diet, physical activity, and other lifestyle factors with cognitive function has been intensively studied with mounting evidence supporting the role of these determinants in the development of cognitive decline and dementia, which is a chief cause of disability globally. Several dietary patterns, foods, and nutrients have been investigated in this regard, with some encouraging and other disappointing results. This review presents the current evidence for the effects of dietary patterns, dietary components, some supplements, physical activity, sleep patterns, and social engagement on the prevention or delay of the onset of age-related cognitive decline and dementia.

Ginkgolide B Alleviates Learning and Memory Impairment in Rats With Vascular Dementia by Reducing Neuroinflammation via Regulating NF-κB Pathway

Ginkgobalide B (GB) as the main active ingredient of traditional Chinese medicine Ginkgo biloba extract is reported to reduce neuroinflammation, protect neurons and promote cognitive learning ability. To explore that GB can reduce neuroinflammation through regulating nuclear factor-kappaB (NF-κB) signaling pathway and overcome cognitive dysfunction in rats with vascular dementia (VD), we aim at investigating the potential effect of GB on enhancing cognitive function in rats with VD. It was found that GB improved survival of oxygen-glucose deprivation (OGD) treated SH-SY5Y cells by attenuating inflammatory response via Toll-like Receptor 4 (TLR4)/NF-κB pathway. When rats were treated with bilateral common carotid artery occlusion (BCCAO) for 24 h, saline and GB were administered in Sprague-Dawley (SD) rats via a single intraperitoneal injection for consecutive 14 days. The behavioral changes of VD like rats treated with GB were observed through open field test, Morris water maze (MWM) and Y-maze electric maze. Nissl staining and immunofluorescence were used to observe changes of neurons in the hippocampus of rats. Western blot analysis was performed by detecting NF-κB pathway related inflammatory factors. The results found that GB can significantly improve the learning and memory ability of VD rats by reducing TLR4/NF-κB mediated neuroinflammation. In conclusion, GB seemed to be a potential drug for amelioration of learning and memory impairment in rats with VD.

Personalized treatment interventions: nonpharmacological and natural treatment strategies in Alzheimer's disease

Introduction: Alzheimer's disease (AD) is a slow, irreversible, progressive, complex, and fatal neurodegenerative disorder. Available pharmacological treatment, known for almost two decades, does not cure the disease, but only alleviates the symptoms, with various efficacy and different side effects. Therefore, there is an unmet need to find other person-centered or personalized approaches to treat AD.Areas covered: This article describes the application of precision medicine-like approaches utilizing nonpharmacological treatment strategies and the use of natural products in personalized care for patients with AD.Expert opinion: Due to the heterogeneity of disease symptoms, somatic conditions, and patient preferences, there is definitely no "one size fits all" intervention. Therefore, individualized treatment choice is based on dementia stage, medical and psychiatric comorbidity, leading symptoms, patient preferences, and remaining capacity of the patient. In the absence of disease-modifying agents, a patient-centered, multidisciplinary team approach appears to be the best option to alleviate the heavy symptomatic burden in this unfortunate population. Hence, appropriate interventions can be offered along the AD continuum, while a better understanding of personal characteristics might help in establishing optimal individualized treatment, as well as its duration and intensity, to deliver interventions in the most effective ways.

Classical Active Ingredients and Extracts of Chinese Herbal Medicines: Pharmacokinetics, Pharmacodynamics, and Molecular Mechanisms for Ischemic Stroke

Stroke is a leading cause of death and disability worldwide, and approximately 87% of cases are attributed to ischemia. The main factors that cause ischemic stroke include excitotoxicity, energy metabolism disorder, Ca⁺ overload, oxidative damage, apoptosis, autophagy, and inflammation. However, no effective drug is currently available for the comprehensive treatment of ischemic stroke in clinical applications; thus, there is an urgent need to find and develop comprehensive and effective drugs to treat postischemic stroke. Traditional Chinese medicine (TCM) has unique advantages in treating ischemic stroke, with overall regulatory effects at multiple levels and on multiple targets. Many researchers have studied the effective components of TCMs and have achieved undeniable results. This paper reviews studies on the anticerebral ischemia effects of TCM monomers such as tetramethylpyrazine (TMP), dl-3-n-butylphthalide (NBP), ginsenoside Rg1 (Rg1), tanshinone IIA (TSA), gastrodin (Gas), and baicalin (BA) as well as effective extracts such as Ginkgo biloba extract (EGB). Research on the anticerebral ischemia effects of TCMs has focused mostly on their antioxidative stress, antiapoptotic, anti-inflammatory, proangiogenic, and proneurogenic effects. However, the research on the use of TCM to treat ischemic stroke remains incompletely characterized. Thus, we summarized and considered this topic from the perspective of pharmacokinetics, pharmacological effects, and mechanistic research, and we have provided a reference basis for future research and development on anticerebral ischemia TCM drugs.

Warfarin and food, herbal or dietary supplement interactions: A systematic review

AIMS

To present an updated overview on the safety of concurrent use of food, herbal or dietary supplement and warfarin.

METHODS

A systematic literature review was performed on 5 databases from inception up to 31 December 2019. These interactions were classified depending on the likelihood of interaction and supporting evidences.

RESULTS

A total of 149 articles describing 78 herbs, food or dietary supplements were reported to interact with warfarin. These reports described potentiation with 45 (57.7%) herbs, food or dietary supplements while 23 (29.5%) reported inhibition and 10 (12.8%) reported limited impact on warfarin pharmacokinetics and pharmacodynamics. Twenty unique herb and dietary supplements also reported to result in minor bleeding events, such as purpura and gum bleeding as well as major events such as intracranial bleeding that led to death.

CONCLUSION

While most food, herbs and supplements can be safely taken in moderation, healthcare professionals should be aware of the increased risk of bleeding when taking several food and herbs. These include Chinese wolfberry, chamomile tea, cannabis, cranberry, chitosan, green tea, Ginkgo biloba, ginger, spinach, St. John's Wort, sushi and smoking tobacco. Patients should be counselled to continue to seek advice from their healthcare professionals when starting any new herbs, food or supplement.

The Neuroprotective Effect of Zingiber cassumunar Roxb. Extract on LPS-Induced Neuronal Cell Loss and Astroglial Activation within the Hippocampus

The systemic administration of lipopolysaccharide (LPS) has been recognized to induce neuroinflammation which plays a significant role in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. In this study, we aimed to determine the protective effect of Zingiber cassumunar (Z. cassumunar) or Phlai (in Thai) against LPS-induced neuronal cell loss and the upregulation of glial fibrillary acidic protein (GFAP) of astrocytes in the hippocampus. Adult male Wistar rats were orally administered with Z. cassumunar extract at various doses (50, 100, and 200 mg/kg body weight) for 14 days before a single injection of LPS (250 μg/kg/i.p.). The results indicated that LPS-treated animals exhibited neuronal cell loss and the activation of astrocytes and also increased proinflammatory cytokine interleukin- (IL-) 1β in the hippocampus. Pretreatment with Z. cassumunar markedly reduced neuronal cell loss in the hippocampus. In addition, Z. cassumunar extract at a dose of 200 mg/kg BW significantly suppressed the inflammatory response by reducing the expression of GFAP and IL-1ß in the hippocampus. Therefore, the results suggested that Z. cassumunar extract might be valuable as a neuroprotective agent in neuroinflammation-induced brain damage. However, further investigations are essential to validate the possible active ingredients and mechanisms of its neuroprotective effect.

Ginkgo Biloba Extract in Ophthalmic and Systemic Disease, With a Focus on Normal-Tension Glaucoma

Glaucoma is a neurodegenerative eye disease that results in retinal ganglion cell loss and ultimately loss of vision. Elevated intraocular pressure (IOP) is the most common known risk factor for retinal ganglion cell damage and visual field loss, and the only modifiable risk factor proven to reduce the development and progression of glaucoma. This has greatly influenced our approach and assessment in terms of diagnosis and treatment. However, as many as ≥50% of patients with progressive vision loss from primary open angle glaucoma without IOP elevation (≤22 mm Hg) have been reported in the United States and Canada; 90% in Japan and 80% in Korea. Extensive research is currently underway to identify the etiology of risk factors for glaucoma other than or in addition to elevated IOP (so-called "normal-tension" glaucoma; NTG) and use this knowledge to expand available treatment options. Currently, Food and Drug Administration-approved medications for glaucoma exclusively target elevated IOP, suggesting the need for additional approaches to treatment options beyond the current scope as the definition of glaucoma changes to encompass cellular and molecular mechanisms. This review focuses on alternative medical approaches, specifically Ginkgo Biloba extract, as a potential treatment option for normal-tension glaucoma.

Efficacy and Safety of Ginkgo biloba in Patients with Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Ginkgo biloba and its extract have been suggested to have a neuroprotective role in patients with acute ischemic stroke. We aimed to examine the efficacy and safety of Ginkgo biloba use in patients with acute ischemic stroke. We searched seven databases for randomized controlled studies examining the use of Ginkgo biloba in patients with acute ischemic stroke. Relevant studies were retrieved, screened, and data were extracted independently by two reviewers. Random effects meta-analyses were performed to evaluate the efficacy and safety outcomes of Ginkgo biloba. We subsequently assessed the certainty of evidence using the GRADE (Grading of Recommendation Assessment, Development and Evaluation) methodology. We found 12 randomized controlled studies enrolling 1466 patients. Pooled results suggest that Ginkgo biloba use was associated with an improvement in neurological function among individuals with AIS with a reduction of 2.87 points on the National Institute of Health Stroke Scale score (95% CI: -4.01--1.74, p<0.001). Ginkgo biloba use was also associated with an improvement in activities of daily living and functional outcome (Mean Difference: 9.52; 4.66-14.33, p<0.001). Subgroup analysis suggest that the impact was larger when using an injectable formulation of Ginkgo biloba compared to the oral formulation. There was no apparent impact of Ginkgo biloba use on all-cause mortality (Risk ratio (RR): 1.21; 0.29-5.09, p=0.80) or cerebrovascular bleeding (RR: 0.82; 0.43-1.57, p=0.55). There was limited evidence on to support the use of gingko biloba in terms of improving quality of life and other stroke events. As such, more studies are needed before it can be recommended for routine use in improving neurological and cognitive function in patients with acute ischemic stroke.

Nanoformulations of Herbal Extracts in Treatment of Neurodegenerative Disorders

Nanotechnology is one of the methods that influenced human life in different ways and is a substantial approach that assists to overcome the multiple limitations of various diseases, particularly neurodegenerative disorders (NDs). Diverse nanostructures such as polymer nanoparticles, lipid nanoparticles, nanoliposomes, nano-micelles, and carbon nanotubes (CNTs); as well as different vehicle systems including poly lactic-co-glycolic acid, lactoferrin, and polybutylcyanoacrylate could significantly increase the effectiveness, reduce the side effects, enhance the stability, and improve the pharmacokinetics of many drugs. NDs belong to a group of annoying and debilitating diseases that involve millions of people worldwide. Previous studies revealed that several nanoformulations from a number of natural products such as curcumin (Cur), quercetin (QC), resveratrol (RSV), piperine (PIP), Ginkgo biloba, and Nigella sativa significantly improved the condition of patients diagnosed with NDs. Drug delivery to the central nervous system (CNS) has several limitations, in which the blood brain barrier (BBB) is the main drawback for treatment of NDs. This review discusses the effects of herbal-based nanoformulations, their advantages and disadvantages, to manage NDs. In summary, we conclude that herbal-based nano systems have promising proficiency in treatment of NDs, either alone or in combination with other drugs.

An Updated Review of Randomized Clinical Trials Testing the Improvement of Cognitive Function of Ginkgo biloba Extract in Healthy People and Alzheimer's Patients

Alzheimer's disease (AD) is a common neurodegenerative disease, mainly manifested by cognitive dysfunction. It seriously reduces the quality of life, and there is no ideal treatment strategy in clinical practice. Clinical studies on the treatment of AD with Ginkgo biloba L. leaf extract (EGb) have been reported since 1980s, and many clinical studies have been carried out during the following 30 years. However, the benefits of EGb on the treatment of AD are still controversial. In this review, we collected the clinical trial reports of EGb on cognitive function from Pubmed, Elsevier, Europe PMC, and other database since the 1980s. Through analysis and comparison, we consider that EGb may be able to improve the cognitive function in patients who suffered from mild dementia during long-term administration (more than 24 weeks) and appropriate dosage (240 mg per day). The main evidences and existing problems of the negative and positive experimental results were summarized.

Neuroprotection mediated by natural products and their chemical derivatives

Neuronal injuries can lead to various diseases such as neurodegenerative diseases, stroke, trauma, ischemia and, more specifically, glaucoma and optic neuritis. The cellular mechanisms that regulate neuronal death include calcium influx and calcium overload, excitatory amino acid release, oxidative stress, inflammation and microglial activation. Much attention has been paid to the effective prevention and treatment of neuroprotective drugs by natural products. This review summarizes the neuroprotective aspects of natural products, extracted from Panax ginseng, Camellia sinensis, soy and some other plants, and some of their chemical derivatives. Their antioxidative and anti-inflammatory action and their inhibition of apoptosis and microglial activation are assessed. This will provide new directions for the development of novel drugs and strategies to treat neurodegenerative diseases.

Theoretical design, preparation, and evaluation of Ginkgolide B molecularly imprinted polymers

Ginkgolide B is in great demand worldwide on account of its extensive and excellent pharmacological effects, however, it is difficult to separate and purify ginkgolide B. In this study, ginkgolide B molecularly imprinted polymers were prepared by combining software simulation and molecular imprinting technique, and its characterization and adsorption performed evaluation were performed to understand the adsorption behavior of the polymers. The adsorption equilibrium concentration of molecularly imprinted polymers was 0.70 mg/mL, and the adsorption equilibrium time was 4 h. Meanwhile, the adsorption isotherm of the polymers for ginkgolide B fitted well with the Langmuir model, and the adsorption kinetics was in line with the pseudo-second-order kinetics. In contrast, the adsorption capacity of molecularly imprinted polymers on ginkgolide B was higher than that of non-molecular imprinted polymers, with better selectivity and better adsorption after repeated use for six times. The application experiments showed that molecular imprinted polymers have a good adsorption effect in low purity samples. Therefore, the polymers reported herein can be expected to apply in the adsorption and separation of ginkgolide B samples.

Medicinal plants and their isolated phytochemicals for the management of chemotherapy-induced neuropathy: therapeutic targets and clinical perspective

BACKGROUND

Chemotherapy, as one of the main approaches of cancer treatment, is accompanied with several adverse effects, including chemotherapy-induced peripheral neuropathy (CIPN). Since current methods to control the condition are not completely effective, new treatment options should be introduced. Medicinal plants can be suitable candidates to be assessed regarding their effects in CIPN. Current paper reviews the available preclinical and clinical studies on the efficacy of herbal medicines in CIPN.

METHODS

Electronic databases including PubMed, Scopus, and Cochrane library were searched with the keywords "neuropathy" in the title/abstract and "plant", "extract", or "herb" in the whole text. Data were collected from inception until April 2018.

RESULTS

Plants such as chamomile (Matricaria chamomilla L.), sage (Salvia officinalis L.), cinnamon (Cinnamomum cassia (L.) D. Don), and sweet flag (Acorus calamus L.) as well as phytochemicals like matrine, curcumin, and thioctic acid have demonstrated beneficial effects in animal models of CIPN via prevention of axonal degeneration, decrease in total calcium level, improvement of endogenous antioxidant defense mechanisms such as superoxide dismutase and reduced glutathione, and regulation of neural cell apoptosis, nuclear factor-ĸB, cyclooxygenase-2, and nitric oxide signaling. Also, five clinical trials have evaluated the effect of herbal products in patients with CIPN.

CONCLUSIONS

There are currently limited clinical evidence on medicinal plants for CIPN which shows the necessity of future mechanistic studies, as well as well-designed clinical trial for further confirmation of the safety and efficacy of herbal medicines in CIPN. Graphical abstract Schematic mechanisms of medicinal plants to prevent chemotherapy-induced neuropathy: NO: nitric oxide, TNF: tumor necrosis factor, PG: prostaglandin, NF-ĸB: nuclear factor kappa B, LPO: lipid peroxidation, ROS: reactive oxygen species, COX: cyclooxygenase, IL: interleukin, ERK: extracellular signal-related kinase, X: inhibition, ↓: induction.

Ginkgo biloba extract protects human melanocytes from H2 O2 -induced oxidative stress by activating Nrf2

Vitiligo is a common skin depigmenting disorder characterized by the loss of functional melanocytes. Its pathogenesis is complicated and oxidative stress plays a critical role in the development of vitiligo. Thus, antioxidant therapy is a promising therapeutic strategy to prevent or even reverse the progression of depigmentation. Ginkgo biloba extract EGb761 has been confirmed to have protective effects on neurons against oxidative stress. Notably, several clinical trials have shown that patients with stable vitiligo achieved repigmentation after taking EGb761. However, the exact mechanism underlying the protective effects of EGb761 on melanocytes against oxidative stress has not been fully elucidated. In the present study, we found that EGb761 effectively protected melanocytes against oxidative stress‐induced apoptosis and alleviated the excessive accumulation of reactive oxygen species (ROS) and lipid peroxidation by enhancing the activity of antioxidative enzymes. Furthermore, the antioxidative effect of EGb761 was achieved by activating Nrf2 and its downstream antioxidative genes. In addition, interfering Nrf2 with siRNA abolished the protective effects of EGb761 on melanocytes against oxidative damage. In conclusion, our study proves that EGb761 could protect melanocytes from H₂O₂‐induced oxidative stress by activating Nrf2. Therefore, EGb761 is supposed to be a potential therapeutic agent for vitiligo.

Epicatechin Gallate Protects HBMVECs from Ischemia/Reperfusion Injury through Ameliorating Apoptosis and Autophagy and Promoting Neovascularization

Green tea is one of the most beverages with antioxidants and nutrients. As one of the major components of green tea, (-)-epicatechin gallate (ECG) was evaluated for its antioxidative properties in the present study. Cell proliferation assay, tube formation, cell migration, apoptosis, and autophagy were performed in human brain microvascular endothelial cells (HBMVECs) after oxygen-glucose deprivation/reoxygenation (OGD/R) to investigate potential anti-ischemia/reperfusion injury properties of ECG in vitro. Markers of oxidative stress as ROS, LDH, MDA, and SOD were further assayed in our study. Data indicated that ECG could affect neovascularization and promote cell proliferation, tube formation, and cell migration while inhibiting apoptosis and autophagy through affecting VEGF, Bcl-2, BAX, LC3B, caspase 3, mTOR, and Beclin-1 expression. All the data suggested that ECG may be protective for the brain against ischemia/reperfusion injury by promoting neovascularization, alleviating apoptosis and autophagy, and promoting cell proliferation in HBMVECs of OGD/R.

Ginaton improves neurological function in ischemic stroke rats via inducing autophagy and maintaining mitochondrial homeostasis

PURPOSE

The present study was carried out to confirm the protective effect of extract of Ginkgo biloba (Ginaton) against ischemic neuronal damage post-treatment at 24 h after reperfusion in rats with middle cerebral artery occlusion (MCAO) and further reveal its possible mechanisms.

METHODS

Adult male Sprague-Dawley rats were modeled by MCAO for 2 h. The rats were divided into three groups: sham, model, and Ginaton (50 mg/kg). All animals received treatment once a day for 14 days from 24 h after reperfusion. Modified neurological severity score test was performed in 1, 7 and 14 days after MCAO, and beam walking test was performed only 14 days after MCAO. Hematoxylin-eosin straining was implemented to measure infarct volume and immunohistochemical analysis was performed to calculate the number of neurons in ischemic cortex penumbra. Western blot was used to evaluate the expression of autophagy (Beclin1, LC3, AMPK, mTOR, ULK), mitochondrial dynamic protein (Parkin, DRP1, OPA1) and apoptosis (Bcl-2, Bax).

RESULTS

Post-treatment with Ginaton for 14 days decreased neurological deficit score, promoted the recovery of motor function, and noticeably reduced infarct size. Besides, Ginaton also alleviated the loss of NeuN-positive cells in ischemic cortex penumbra. In ischemic cortex, Ginaton increased the expression of Beclin1 and LC3-Ⅱ, elevated the AMPK, mTOR and ULK1, and induced autophagy. Moreover, Ginaton treatment upregulated Parkin, DRP1, and OPA1, and elevated the ratio of Bcl-2/Bax in 14 days after MCAO reperfusion injury.

CONCLUSION

Ginaton exhibited obvious neuroprotective effects in MCAO rats with initial administered 24 h after MCAO. The mechanism of Ginaton included induction of autophagy via activation of the AMPK pathway, maintenance of mitochondrial homeostasis and inhibition of apoptosis.

Neuroprotective Role of Hypothermia in Hypoxic-ischemic Brain Injury: Combined Therapies using Estrogen

Hypoxic-ischemic brain injury is a complex network of factors, which is mainly characterized by a decrease in levels of oxygen concentration and blood flow, which lead to an inefficient supply of nutrients to the brain. Hypoxic-ischemic brain injury can be found in perinatal asphyxia and ischemic-stroke, which represent one of the main causes of mortality and morbidity in children and adults worldwide. Therefore, knowledge of underlying mechanisms triggering these insults may help establish neuroprotective treatments. Selective Estrogen Receptor Modulators and Selective Tissue Estrogenic Activity Regulators exert several neuroprotective effects, including a decrease of reactive oxygen species, maintenance of cell viability, mitochondrial survival, among others. However, these strategies represent a traditional approach of targeting a single factor of pathology without satisfactory results. Hence, combined therapies, such as the administration of therapeutic hypothermia with a complementary neuroprotective agent, constitute a promising alternative. In this sense, the present review summarizes the underlying mechanisms of hypoxic-ischemic brain injury and compiles several neuroprotective strategies, including Selective Estrogen Receptor Modulators and Selective Tissue Estrogenic Activity Regulators, which represent putative agents for combined therapies with therapeutic hypothermia.

Potential role of α-lipoic acid and Ginkgo biloba against silver nanoparticles-induced neuronal apoptosis and blood-brain barrier impairments in rats

AIMS

This study explored whether silver nanoparticles (AgNPs) can disrupt tight-junctions integrity resulted in blood-brain barrier dysfunction along with oxidative stress, pro-inflammation, and apoptosis induction. Additionally, neuroprotective activities of α-lipoic acid (LA) and Ginkgo biloba (GB) were investigated.

MAIN METHODS

Forty adults rats were enrolled into; Control, AgNPs (50 mg/kg), LA (100 mg/kg) + AgNPs, and GB (120 mg/kg) + AgNPs. After 30 days, neuronal changes were assessed biochemically and histopathologically. Brain tissues oxidative indices, mRNA expression of proinflammatory cytokines and tight-junction proteins and pro-apoptotic biomarker, caspase-3 were investigated.

KEY FINDINGS

AgNPs exposure enhanced lipid peroxidation (+195%) along with declines in glutathione (-43%), glutathione peroxidase (-34%), glutathione S-transferase (-31%), catalase (-43%), and superoxide dismutase (-38%) activities in brain tissues. The apparent brain oxidative damage was associated with obvious neuronal dysfunction that was ascertained by neuropathological lesions. AgNPs lowered serum acetylcholine esterase, iron and copper levels, and increased creatine phosphokinase and creatine phosphokinase-brain type activities. Following AgNPs exposure, brain silver and iron contents were increased, but the copper level was decreased. AgNPs up-regulated TNF-α (6.5-fold) and IL-1β (8.9-fold) transcript levels, and simultaneously over-expressed the caspase-3 protein in cerebrum and cerebellum inducing cell apoptosis. Moreover, AgNPs down-regulated the transcript levels of tight-junction proteins; JP-1 (0.65-fold) and JAM-3(0.81-fold).

SIGNIFICANCE

LA and relatively GB improved the serious effects of AgNPs on the blood-brain barrier function and tight-junction proteins through their antioxidants, anti-inflammatory, and anti-apoptotic efficacies. Co-treatment with LA or GB may be favorable in ameliorating the neurotoxic side effects of AgNPs.

Clinical and genomic safety of treatment with Ginkgo biloba L. leaf extract (IDN 5933/Ginkgoselect®Plus) in elderly: a randomised placebo-controlled clinical trial [GiBiEx]

BACKGROUND

Numerous health benefits have been attributed to the Ginkgo biloba leaf extract (GBLE), one of the most extensively used phytopharmaceutical drugs worldwide. Recently, concerns of the safety of the extract have been raised after a report from US National Toxicology Program (NTP) claimed high doses of GBLE increased liver and thyroid cancer incidence in mice and rats. A safety study has been designed to assess, in a population of elderly residents in nursing homes, clinical and genomic risks associated to GBLE treatment.

METHODS

GiBiEx is a multicentre randomized clinical trial, placebo controlled, double blinded, which compared subjects randomized to twice-daily doses of either 120-mg of IDN 5933 (also known as Ginkgoselect®Plus) or to placebo for a 6-months period. IDN 5933 is extracted from dried leaves and contains 24.3% flavone glycosides and 6.1% of terpene lactones (2.9% bilobalide, 1.38% ginkgolide A, 0.66% ginkgolide B, 1.12% ginkgolide C) as determined by HPLC. The study was completed by 47 subjects, 20 in the placebo group and 27 in the treatment group. Clinical (adverse clinical effect and liver injury) and genomic (micronucleus frequency, comet assay, c-myc, p53, and ctnnb1 expression profile in lymphocytes) endpoints were assessed at the start and at the end of the study.

RESULTS

No adverse clinical effects or increase of liver injury markers were reported in the treatment group. The frequency of micronuclei [Mean Ratio (MR) = 1.01, 95% Confidence Intervals (95% CI) 0.86-1.18), and DNA breaks (comet assay) (MR = 0.91; 95% CI 0.58-1.43), did not differ in the two study groups. No significant difference was found in the expression profile of the three genes investigated.

CONCLUSIONS

None of the markers investigated revealed a higher risk in the treatment group, supporting the safety of IDN 5933 at doses prescribed and for duration of six months.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03004508 , December 20, 2016. Trial retrospectively registered.