Bilobalide, a unique constituent of Ginkgo biloba, inhibits inflammatory pain in rats

Plant-Based Therapies to Ameliorate Neuroinflammation in Parkinson's Disease, Alzheimer's Disease, and Epilepsy: A Narrative Review

Neuroinflammation plays a crucial role in the etiology of neurodegenerative diseases such as Parkinson's disease (PD), Alzheimer's disease (AD), and epilepsy. Several key inflammatory pathways are pivotal in the development of neuroinflammation in PD, AD, and epilepsy. The NF-κB pathway is a central regulator of inflammation, and its chronic activation triggers the transcription of genes that drive inflammatory responses. JAK-STAT signaling system triggers the production of cytokines and chemokines that generate neuroinflammation; mitogen-activated protein kinases mediate the p38 pathway and control the synthesis of cytokines. Activation of the NO signaling pathway causes oxidative stress and neuronal damage. Plant-based therapeutics are gaining attention due to their anti-neuroinflammatory and neuroprotective phytochemicals, which shield the neurons from damage. Some of the examples are curcumin, resveratrol, ginsenosides, cannabidiol, notoginseng, quercetin, and so on. Clinical studies also indicate that certain plant-based formulations like Wei Li Bai, IPX066, Bushen huoxue, and so on can be effective alternatives to presently available remedies. The review is an attempt at assimilating the information from available literature on the role of different neurotransmitters involved in neuroinflammation and their connection in AD, PD, and epilepsy and applications of plant-based therapies in the prevention and cure of the above-mentioned diseases.

Lactone-to-Lactam Editing Alters the Pharmacology of Bilobalide

Precise transformations of natural products (NPs) can fine-tune their physicochemical properties while preserving inherently complex and evolutionarily optimized parent scaffolds. Here, we report an unprecedented lactone-to-lactam transformation on bilobalide, thus improving its stability and paving the way for biological exploration of previously inaccessible chemical space that is highly representative of the parent structure. This late-stage molecular editing of bilobalide enables facile access to a unique library of lactam analogues with altered pharmacology. Through phenotypic screening, we identify BB10 as a hit compound with unexpected inhibition of ferroptotic cell death. We further reveal that BB10 suppresses ferroptosis by restoring the expression of glutathione peroxidase 4 (GPX4) in brain cells. This study highlights that even subtle changes on NP scaffolds can confer new pharmacological properties, inspiring the exploration of simple yet critical transformations on complex NPs.

Design of Mixed Medicinal Plants, Rich in Polyphenols, Vitamins B, and Palmitoylethanolamide-Based Supplement to Help Reduce Nerve Pain: A Preclinical Study

Neuropathy affects 7-10% of the general population and is caused by a lesion or disease of the somatosensory system. The limitations of current therapies highlight the necessity of a new innovative approach to treating neuropathic pain (NP) based on the close correlation between oxidative stress, inflammatory process, and antioxidant action. The advantageous outcomes of a novel combination composed of Hop extract, Propolis, Ginkgo Biloba, Vitamin B, and palmitoylethanolamide (PEA) used as a treatment was evaluated in this study. To assess the absorption and biodistribution of the combination, its bioavailability was first examined in a 3D intestinal barrier model that replicated intestinal absorption. Further, a 3D nerve tissue model was developed to study the biological impacts of the combination during the essential pathways involved in NP. Our findings show that the combination could cross the intestinal barrier and reach the peripheral nervous system, where it modulates the oxidative stress, inflammation levels, and myelination mechanism (increased NRG, MPZ, ERB, and p75 levels) under Schwann cells damaging. This study proves the effectiveness of Ginkgo Biloba, Propolis, Hop extract, Vitamin B, and PEA in avoiding nerve damage and suggests a potential alternative nutraceutical treatment for NP and neuropathies.

Bilobalide Prevents Apoptosis and Improves Cardiac Function in Myocardial Infarction

Myocardial infarction (MI) is an extremely severe cardiovascular disease, which ranks as the leading cause of sudden death worldwide. Studies have proved that cardiac injury following MI can cause cardiomyocyte apoptosis and myocardial fibrosis. Bilobalide (Bilo) from Ginkgo biloba leaves have been widely reported to possess excellent cardioprotective effects. However, concrete roles of Bilo in MI have not been investigated yet. We here designed both in vitro and in vivo experiments to explore the effects of Bilo on MI-induced cardiac injury and the underlying mechanisms of its action. We conducted in vitro experiments using oxygen-glucose deprivation (OGD)-treated H9c2 cells. Cell apoptosis in H9c2 cells was assessed by conducting flow cytometry assay and evaluating apoptosis-related proteins with western blotting. MI mouse model was established by performing left anterior descending artery (LAD) ligation. Cardiac function of MI mice was determined by assessing ejection fraction (EF), fractional shortening (FS), left ventricular end-systolic diameter (LVESD), and left ventricular end-diastolic diameter (LVEDD). Histological changes were analyzed, infarct size and myocardial fibrosis were measured by hematoxylin and eosin (H&E) and Masson staining in cardiac tissues from the mice. The apoptosis of cardiomyocytes in MI mice was assessed by TUNEL staining. Western blotting was applied to detect the effect of Bilo on c-Jun N-terminal kinase (JNK)/p38 mitogen-activated protein kinases (p38 MAPK) signaling both in vitro and in vivo. Bilo inhibited OGD-induced cell apoptosis and lactate dehydrogenase (LDH) release in H9c2 cells. The protein levels of p-JNK and p-p38 were significantly downregulated by Bilo treatment. SB20358 (inhibitor of p38) and SP600125 (inhibitor of JNK) suppressed OGD-induced cell apoptosis as Bilo did. In MI mouse model, Bilo improved the cardiac function and significantly reduced the infarct size and myocardial fibrosis. Bilo inhibited MI-induced cardiomyocytes apoptosis in mice. Bilo suppressed the protein levels of p-JNK and p-p38 in cardiac tissues from MI mice. Bilo alleviated OGD-induced cell apoptosis in H9c2 cells and suppressed MI-induced cardiomyocyte apoptosis and myocardial fibrosis in mice via the inactivation of JNK/p38 MAPK signaling pathways. Thus, Bilo may be an effective anti-MI agent.

Identifying inflammation-related targets of natural lactones using network pharmacology, molecular modeling and in vitro approaches

Natural lactones have been used in traditional and folklore medicine for centuries owing to their anti-inflammatory properties. The study uses a multifaceted approach to identify lead anti-inflammatory lactones from the SISTEMATX natural products database. The study analyzed the natural lactone database, revealing 18 lactones linked to inflammation targets. The primary targets were PTGES, PTGS1, COX-2, ALOX5 and IL1B. STX 12273 was the best hit, with the lowest binding energy and potential for inhibiting the COX-2 enzyme. The study suggested natural lactone, STX 12273, from the SISTEMATX database with anti-inflammatory potential and postulated its use for inflammation treatment or prevention.

Safety Assessment of Ginkgo biloba-Derived Ingredients as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of 10 Ginkgo biloba-derived ingredients, which are most frequently reported to function in cosmetics as skin conditioning agents or antioxidants. The Panel reviewed the available data to determine the safety of these ingredients. Because final product formulations may contain multiple botanicals, each containing the same constituents of concern, formulators are advised to be aware of these constituents and to avoid reaching levels that may be hazardous to consumers. The Panel was concerned about the presence of ginkgolic acid in cosmetics. Industry should use good manufacturing practices to limit impurities. The Panel concluded that 5 Ginkgo biloba leaf-derived ingredients are safe in the present practices of use and concentration described in this safety assessment when formulated to be non-sensitizing; data are insufficient to determine the safety of the remaining 5 ingredients under the intended conditions of use in cosmetic formulations.

Prevention of Bleomycin-Induced Pulmonary Inflammation and Fibrosis in Mice by Bilobalide

Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease. Bilobalide (BB) is a sesquiterpene isolated from Ginkgo biloba, and its role in IPF is poorly understood. Mice were intratracheally instilled with 2.5 mg/kg bleomycin (BLM) to induce IPF and then treated with 2.5, 5, and 10 mg/kg BB daily for 21 days. Treatment with BB ameliorated pathological injury and fibrosis of lung tissues in BLM-induced mice. BB suppressed BLM-induced inflammatory response in mice as demonstrated by reduced inflammatory cells counts (leukocytes, neutrophils, macrophages, and lymphocytes) and pro-inflammatory factors (CCL2 and TNF-α), as well as increased CXCL10 levels in BALF. The expression of BLM-induced hydroxyproline, LDH, and pro-fibrotic mediators including fibronectin, collagen I, α-smooth muscle actin (α-SMA), transforming growth factor (TGF)-β1, matrix metalloproteinase (MMP)-2, and MMP-9 in lung tissue was inhibited by BB treatment, and the tissue inhibitor of metalloproteinase-1 (TIMP-1) expression was increased. BB blocked the phosphorylation of JNK and NF-κB, and the nuclear translocation of NF-κB in the lung tissue of mice induced by BLM. Additionally, it abated the activation of NLRP3 inflammasome in lung tissue induced by BLM, which led to the downregulation of IL-18 and IL-1β in BALF. Our present study suggested that BB might ameliorate BLM-induced pulmonary fibrosis by inhibiting the early inflammatory response, which is probably via the inhibition of the JNK/NF-κB/NLRP3 signal pathway. Thus, BB might serve as a therapeutic potential agent for pulmonary inflammation and fibrosis.

CB1 as a novel target for Ginkgo biloba's terpene trilactone for controlling chemotherapy-induced peripheral neuropathy (CIPN)

The application of antineoplastic chemotherapeutic agents causes a common side effect known as chemotherapy-induced peripheral neuropathy (CIPN) that leads to reducing the quality of patient's life. This research involves the performance of molecular docking and molecular dynamic (MD) simulation studies to explore the impact of terpenoids of Ginkgo biloba on the targets (CB-1, TLR4, FAAH-1, COX-1, COX-2) that can significantly affect the controlling of CIPN's symptoms. According to the in-vitro and in-vivo investigations, terpenoids, particularly ginkgolides B, A, and bilobalide, can cause significant effects on neuropathic pain. The molecular docking results disclosed the tendency of our ligands to interact with mainly CB1 and FAAH-1, as well as partly with TLR4, throughout their interactions with targets. Terpene trilactone can exhibit a lower rate of binding energy than CB1's inhibitor (7dy), while being precisely located in the CB1's active site and capable of inducing stable interactions by forming hydrogen bonds. The analyses of MD simulation proved that ginkgolide B was a more suitable activator and inhibitor for CB1 and TLR4, respectively, when compared to bilobalide and ginkgolide A. Moreover, bilobalide is capable of inhibiting FAAH-1 more effectively than the two other ligands. According to the analyses of ADME, every three ligands followed the Lipinski's rule of five. Considering these facts, the exertion of three ligands is recommended for their anti-inflammatory, neuroprotective, and anti-nociception influences caused by primarily activating CB1 and inhibiting FAAH-1 and TLR4; in this regard, these compounds can stand as potential candidates for the control and treatment of CIPN's symptoms.

Bilobalide Exerts Anti-Inflammatory Effects on Chondrocytes Through the AMPK/SIRT1/mTOR Pathway to Attenuate ACLT-Induced Post-Traumatic Osteoarthritis in Rats

Although osteoarthritis (OA) significantly affects the quality of life of the elderly, there is still no effective treatment strategy. The standardized Ginkgo biloba L. extract preparation has been shown to have a wide range of therapeutic effects. Bilobalide, a unique ingredient of Ginkgo biloba, has anti-inflammatory and antioxidant pharmacological properties, but its mechanism of action on OA remains unknown. In this study, we investigated the effects of bilobalide on the development of OA through in vivo and in vitro experiments, as well as its potential anti-inflammatory mechanisms. The in vitro experiments demonstrated that bilobalide significantly inhibited the production of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and matrix metalloproteinase 13 (MMP13) in ATDC5 chondrocytes induced by Interleukin-1β (IL-1β). At the molecular level, bilobalide induced chondrocyte autophagy by activating the AMPK/SIRT1/mTOR signaling pathway, which increased the expression of autophagy-related Atg genes, up-regulated the expression of LC3 protein, and reduced the expression of the p62 protein. In vivo, bilobalide exerted significant anti-inflammatory and anti-extracellular matrix (ECM) degradation effects in a rat model of post-traumatic OA (PTOA) induced by anterior cruciate ligament transection (ACLT). Bilobalide could relieve joint pain in PTOA rats, inhibit the expression of iNOS and COX-2 protein in cartilage via the AMPK/SIRT1/mTOR pathway, and reduce the level of ECM degradation biomarkers in serum. In conclusion, bilobalide exhibits vigorous anti-inflammatory activity, presenting it as an interesting potential therapeutic agent for OA.

Protective Effects of Ginkgolide on a Cellular Model of Alzheimer's Disease via Suppression of the NF-κB Signaling Pathway

NF-κB signaling has been reported to play a key regulatory role in the pathogenesis of Alzheimer’s disease (AD). The purpose of this study is to investigate the effects of ginkgolide on cell viability in an AD cellular model involving an APP/PS1 double gene-transfected HEK293 cell line (APP/PS1-HEK293) and further explore the mechanisms of action related to NF-κB signaling. The optimal time point and concentration of ginkgolide for cell proliferation were screened using a cell counting kit-8 assay. Based on the results, an in vitro study was performed by co-culture of APP/PS1-HEK293 with different dosages of ginkgolide, followed by an enzyme-linked immunosorbent assay to measure the levels of supernatant tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6, as well as western blotting and real-time polymerase chain reaction to detect intracellular protein and mRNA expression of NF-κB p65, IκBa, Bcl-2, and Bax. APP/PS1-HEK293 cells exhibited the highest cell viability at a concentration of 100 µg/ml after 48 h of treatment with ginkgolide. The supernatant levels of TNF-α, IL-1β, and IL-6 in the high-dosage ginkgolide-treated groups were lower than those in the control group. Compared with the control group, there were decreased intracellular protein and mRNA expression of NF-κB p65 and Bax, but increased protein and mRNA expression of IκBa in both high-dosage and low-dosage groups. Ginkgolide may enhance cell viability, indicative of its neuroprotective effects on AD, at least partially via suppression of the NF-κB signaling pathway involving anti-apoptosis and anti-inflammation mechanisms. Therefore, ginkgolide might be a promising therapeutic agent against AD.

Ganoderic Acid A Alleviates OVA-Induced Asthma in Mice

The aim of this study is to investigate the effects of ganoderic acid A (GAA) on OVA-induced asthma in mice. Mouse asthma model was established by ovalbumin (OVA) in vitro. Diff-Quik staining was used to observe the total numbers of cells and the number of classification cells in each group, and HE staining was used to observe lung inflammation in lung tissue sections. ELISA was used to detect the effect of GAA on the levels of interleukin-4 (IL-4), IL-5, and IL-13 in serum and lung tissue. The expression levels of TLR/NF-κB were detected by Western blot. Immunohistochemistry was used to observe the expression changes of TLR4 and P-P65. Compared with the normal group, the inflammatory cell count, IL-4, IL-5, and IL-13 expression in the model group increased, and TLR/NF-kB signal protein expression increased. Compared with the model group, in GAA group, the number of inflammatory cells, the expression of IL-4, IL-5, and IL-13 decreased, and the expression of TLR/NF-kB signaling protein decreased. GAA regulated lung inflammation in asthmatic mice by inhibiting TLR/NF-kB signaling pathway.

Ginkgolic Acid Inhibits Coronavirus Strain 229E Infection of Human Epithelial Lung Cells

Since December 2019, the COVID-19 pandemic has affected more than 200 million individuals around the globe and caused millions of deaths. Although there are now multiple vaccines for SARS-CoV-2, their efficacy may be limited by current and future viral mutations. Therefore, effective antiviral compounds are an essential component to win the battle against the family of coronaviruses. Ginkgolic Acid (GA) is a pan-antiviral molecule with proven effective in vitro and in vivo activity. We previously demonstrated that GA inhibits Herpes Simplex Virus 1 (HSV-1) by disrupting viral structure, blocking fusion, and inhibiting viral protein synthesis. Additionally, we reported that GA displays broad-spectrum fusion inhibition encompassing all three classes of fusion proteins, including those of HIV, Ebola, influenza A, and Epstein Barr virus. Here, we report that GA exhibited potent antiviral activity against Human Coronavirus strain 229E (HCoV-229E) infection of human epithelial lung cells (MRC-5). GA significantly reduced progeny virus production, expression of viral proteins, and cytopathic effects (CPE). Furthermore, GA significantly inhibited HCoV-229E even when added post-infection. In light of our findings and the similarities of this family of viruses, GA holds promising potential as an effective antiviral treatment for SARS-CoV-2.

Bilobalide: A review of its pharmacology, pharmacokinetics, toxicity, and safety

Bilobalide is a natural sesquiterpene trilactone from Ginkgo biloba leaves. It has good water solubility and is widely used in food and pharmaceutical fields. In the last decade, a plethora of studies on the pharmacological activities of bilobalide has been conducted and demonstrated that bilobalide possessed an extensive range of pharmacological activities such as neuroprotective, antioxidative, antiinflammatory, anti-ischemic, and cardiovascular protective activities. Pharmacokinetic studies indicated that bilobalide may have the characteristics of rapid absorption, good bioavailability, wide distribution, and slow elimination. This review aims to summarize the advances in pharmacological, pharmacokinetics, toxicity, and safety studies of bilobalide in the last decade with an emphasis on its neuroprotective and antiinflammatory activities, to provide researchers with the latest information and point out the limitations of relevant research at the current stage and the aspects that should be strengthened in future research.

Fungal Endophytes as Efficient Sources of Plant-Derived Bioactive Compounds and Their Prospective Applications in Natural Product Drug Discovery: Insights, Avenues, and Challenges

Fungal endophytes are well-established sources of biologically active natural compounds with many producing pharmacologically valuable specific plant-derived products. This review details typical plant-derived medicinal compounds of several classes, including alkaloids, coumarins, flavonoids, glycosides, lignans, phenylpropanoids, quinones, saponins, terpenoids, and xanthones that are produced by endophytic fungi. This review covers the studies carried out since the first report of taxol biosynthesis by endophytic Taxomyces andreanae in 1993 up to mid-2020. The article also highlights the prospects of endophyte-dependent biosynthesis of such plant-derived pharmacologically active compounds and the bottlenecks in the commercialization of this novel approach in the area of drug discovery. After recent updates in the field of 'omics' and 'one strain many compounds' (OSMAC) approach, fungal endophytes have emerged as strong unconventional source of such prized products.

Bilobalide protects against ischemia/reperfusion-induced oxidative stress and inflammatory responses via the MAPK/NF-휅B pathways in rats

Background

Clinically, skeletal muscle ischemia/reperfusion injury is a life-threatening syndrome that is often caused by skeletal muscle damage and is characterized by oxidative stress and inflammatory responses. Bilobalide has been found to have antioxidative and anti-inflammatory effects. However, it is unclear whether bilobalide can protect skeletal muscle from ischemia/reperfusion injury.

Methods

The effects of bilobalide on ischemia/reperfusion-injured skeletal muscle were investigated by performing hematoxylin and eosin staining and assessing the wet weight/dry weight ratio of muscle tissue. Then, we measured lipid peroxidation, antioxidant activity and inflammatory cytokine levels. Moreover, Western blotting was conducted to examine the protein levels of MAPK/NF-휅B pathway members.

Results

Bilobalide treatment could protected hind limb skeletal muscle from ischemia/reperfusion injury by alleviating oxidative stress and inflammatory responses via the MAPK/NF-휅B pathways.

Conclusions

Bilobalide may be a promising drug for I/R-injured muscle tissue. However, the specific mechanisms for the protective effects still need further study.

Bilobalide Alleviated Dextran Sulfate Sodium-Induced Experimental Colitis by Inhibiting M1 Macrophage Polarization Through the NF-κB Signaling Pathway

Bilobalide, a unique Ginkgo biloba constituent has attracted significant interest as a novel therapeutic option for neuronal protection. However, there is paucity of data on its effect on colitis. This work sought to evaluate the effect of bilobalide on macrophage polarization in vitro and dextran sulfate sodium (DSS) induced colitis in vivo. Through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and annexin V/PI assay, it was shown that bilobalide has no significant toxicity on macrophage. Lipopolysaccharide (LPS) and interferon-gamma (IFN-γ) induced macrophage activation and polarization were significantly suppressed by bilobalide as indicated by reduced expression of cytokine, major histocompatibility complex II (MHC-II), and CD11c. Pertinently, the signaling pathway study showed that the phosphorylation of p65 and its nuclear translocation were decreased while STAT1 was not affected. In DSS-treated mice, administration (i.g) of three doses of bilobalide na\mely 1.25 mg/kg (low dose group), 2.5 mg/kg (medium dose group), and 5 mg/kg (high dose group) was performed daily starting from day 1 to day 10. Medium and high dose bilobalide markedly reduced the inflammation of colitis proved via elevation of bodyweight, decrement in disease activity index (DAI), alleviation of colon damage as well as reduction in activity of colon tissue myeloperoxidase activity. In accordance with the in vitro results, the levels of inflammatory cytokines such as interleukin 6 (IL-6), IL-1β, and tumor necrosis factor (TNF-α) in serum as well as messenger RNA (mRNA) expression in colon were obviously reduced in the bilobalide treated groups. Also, factor nuclear factor kappa B (NF-κB) signaling pathway was decreased significantly by bilobalide treatment. Collectively, these results indicated that administration of bilobalide improved experimental colitis via inhibition of M1 macrophage polarization through the NF-κB signaling pathway. Thus, bilobalide could act as a potential drug for the treatment of inflammatory bowel disease (IBD) in the not-too-distant future.

Bilobalide assuages morphine-induced addiction in hippocampal neuron cells through upregulation of microRNA-101

Bilobalide exhibits many biological activities, but its effects on morphine stimulation have not been elucidated. The research aims to explore the function and underlying mechanisms of bilobalide in morphine-led hippocampal neuron cells. Cells were treated with or without morphine or oxaliplatin (OXA), bilobalide, or SCH772984 dilutions. miR-101 inhibitor and negative control were transfected into cells. Western blot and quantitative reverse transcription-polymerase chain reaction were, respectively, conducted to measure the relative expression of proteins or RNAs. Morphine improved the expression levels of orexin1 receptor (OX1R) and c-FOS, the p/t-ERK/PKC as well. The c-FOS protein level and p/t-ERK/PKC were significantly elevated by morphine + OXA. Bilobalide had no effect on OX1R and p/t-PKC but evidently decreased the c-FOS and p/t-ERK. The p-ERK and the c-FOS accumulation levels were remarkably reduced by SCH772984. The production of miR-101 was promoted by bilobalide but inhibited by the miR-101 inhibitor. miR-101 inhibitor abolished bilobalide's inhibitory effects on p/t-ERK. Bilobalide exhibited morphine-induced effects on hippocampal neuron cells by upregulating miR-101.

Bilobalide protects astrocytes from oxygen and glucose deprivation-induced oxidative injury by upregulating manganese superoxide dismutase

Bilobalide (BB), a constituent of the Ginkgo biloba extract, is a neuroprotective agent with multiple mechanisms of action. To further explore the potential therapeutic effects of BB in stroke, we investigated its effects on primary astrocytes using the oxygen and glucose deprivation-reoxygenation (OGD-R) model. Cell viability was measured by lactate dehydrogenase release assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cell death was measured by annexin 5 conjgated with fluorescein isothiocyanate (V-FITC) assay, and reactive oxygen species (ROS) production was measured by 2',7'-Dichlorodihydrofluorescein Diacetate (DCFH-DA) probe. Manganese superoxide dismutase (MnSOD) expression was measured by western blot and immunofluorescence. Mitochondrial membrane potential was monitored using JC-1 staining. Our results show that OGD-R downregulated MnSOD and impaired mitochondrial function, which further enhanced ROS production in primary astrocytes. As a result, cell viability was compromised, and cell death increased. BB treatment protected astrocytes from those injuries mainly by restoring MnSOD level as MnSOD inhibitor abolished the effects of BB. In conclusion, we demonstrated that OGD-R induced astrocytic injury, but BB increased the expression of MnSOD, the ROS scavenger, to reverse the exacerbated astrocytic injury.

Recent development in antihyperalgesic effect of phytochemicals: anti-inflammatory and neuro-modulatory actions

INTRODUCTION

Pain is an unpleasant sensation triggered by noxious stimulation. It is one of the most prevalent conditions, limiting productivity and diminishing quality of life. Non steroidal anti inflammatory drugs (NSAIDs) are widely used as pain relievers in present day practice as pain is mostly initiated due to inflammation. However, due to potentially serious side effects, long term use of these antihyperalgesic drugs raises concern. Therefore there is a demand to search novel medicines with least side effects. Herbal products have been used for centuries to reduce pain and inflammation, and phytochemicals are known to cause fewer side effects. However, identification of active phytochemicals of herbal medicines and clear understanding of the molecular mechanism of their action is needed for clinical acceptance.

MATERIALS AND METHODS

In this review, we have briefly discussed the cellular and molecular changes during hyperalgesia via inflammatory mediators and neuro-modulatory action involved therein. The review includes 54 recently reported phytochemicals with antihyperalgesic action, as per the literature available with PubMed, Google Scholar and Scopus.

CONCLUSION

Compounds of high interest as potential antihyperalgesic agents are: curcumin, resveratrol, capsaicin, quercetin, eugenol, naringenin and epigallocatechin gallate (EGCG). Current knowledge about molecular targets of pain and their regulation by these phytochemicals is elaborated and the scope of further research is discussed.

Bilobalide alleviates depression-like behavior and cognitive deficit induced by chronic unpredictable mild stress in mice

Bilobalide (BB), a unique constituent of Ginkgo biloba, has powerful neuroprotection and stress-alleviating properties. However, whether BB exerts a positive effect on depression and cognitive deficit induced by chronic stress is not known. The present study was designed to investigate the influence of BB on depression and cognitive impairments induced by chronic unpredictable mild stress (CUMS) in mice. During daily exposure to stressors for 5 consecutive weeks, mice were administered BB at the doses of 0, 3, or 6 mg/kg/day intraperitoneally. We replicated the finding that CUMS induced depression-like behavior and cognitive deficits as the CUMS+vehicle (VEH) group showed a significant increase in immobility in the tail suspension test, a decrease in the discrimination index of the novel object recognition task, and increased latency to platform and decreased number of platform crossings in the Morris water maze compared with the control+VEH group. Chronic administration of BB effectively reversed these alterations. In addition, the CUMS+VEH group showed significantly higher levels of baseline serum corticosterone than those of the control+VEH group and BB dose-dependently inhibited this effect. Our results suggest that BB may be useful for inhibition of depression-like behavior and cognitive deficits, and this protective effect was possibly exerted partly through an action on the hypothalamic-pituitary-adrenal axis.

Current Perspectives on the Beneficial Role of Ginkgo biloba in Neurological and Cerebrovascular Disorders

Ginkgo biloba extract is an alternative medicine available as a standardized formulation, EGb 761^®, which consists of ginkgolides, bilobalide, and flavonoids. The individual constituents have varying therapeutic mechanisms that contribute to the pharmacological activity of the extract as a whole. Recent studies show anxiolytic properties of ginkgolide A, migraine with aura treatment by ginkgolide B, a reduction in ischemia-induced glutamate excitotoxicity by bilobalide, and an alternative antihypertensive property of quercetin, among others. These findings have been observed in EGb 761 as well and have led to clinical investigation into its use as a therapeutic for conditions such as cognition, dementia, cardiovascular, and cerebrovascular diseases. This review explores the therapeutic mechanisms of the individual EGb 761 constituents to explain the pharmacology as a whole and its clinical application to cardiovascular and neurological disorders, in particular ischemic stroke.

Bilobol inhibits the lipopolysaccharide-induced expression and distribution of RhoA in HepG2 human hepatocellular carcinoma cells

Recent studies have revealed the localization of RhoA protein in the cell nucleus, in addition to its distribution in the cytosol and cell membrane. The results of previous studies by our group indicated that nuclear RhoA expression is increased, or RhoA is transported into the nucleus, when cells become cancerous or damaged. Furthermore, application of the anticancer agent Taxol appeared to reduce nuclear RhoA localization, indicating an association between the nuclear translocation of RhoA and tumor progression. Bilobol is a traditional Chinese medicine ingredient, however, its anticancer effect has remained unclear. The present study aimed to demonstrate the anticarcinogenic action of bilobol against hepatocellular carcinoma, in order to lay the foundations for subsequent research into the mechanisms underlying its anticancer effects. In the present study, HepG2 cells were treated with lipopolysaccharide (LPS), to induce inflammation, and/or bilobol. By performing an ELISA, it was observed that bilobol was able to suppress the inflammation induced by LPS. In addition, immunofluorescence and western blot analyses indicated that bilobol may reduce the expression of RhoA, suppress translocation of RhoA into the nucleus and inhibit the RhoA/Rho-associated protein kinase signaling pathway. In conclusion, the present study revealed the potential anticancer effects of bilobol.

A dermocosmetic containing bakuchiol, Ginkgo biloba extract and mannitol improves the efficacy of adapalene in patients with acne vulgaris: result from a controlled randomized trial

BACKGROUND

Acne vulgaris is an inflammatory disorder of the pilosebaceous unit.

AIM

To confirm that BGM (bakuchiol, Ginkgo biloba extract, and mannitol) complex increases the established clinical efficacy of adapalene 0.1% gel in patients with acne.

METHODS

A clinical trial was conducted in acne patients. A total of 111 subjects received adapalene 0.1% gel and BGM complex or vehicle cream for 2 months. Assessments comprised Investigator Global Assessment (IGA), global efficacy, seborrhea intensity, inflammatory and non-inflammatory lesions, and subject perception, as well as overall safety and local tolerance and quality of life.

RESULTS

At the end of the trial, inflammatory and non-inflammatory lesions, IGA, global efficacy, and seborrhea intensity had significantly improved in both treatment groups. Differences were statistically significant (P<0.05) in favor of BGM complex for inflammatory lesions as well as IGA and seborrhea intensity. Global efficacy assessments and subject perception confirmed the superiority of BGM complex-including treatment over the comparative combination. Quality of life had improved more with the active combination than with the vehicle combination. In the active group, four subjects had to interrupt temporarily BGM complex and 12 adapalene compared to seven subjects interrupting the vehicle and eleven adapalene in the vehicle group. One subject withdrew from the trial due to an allergy to adapalene. The majority of all events were mild.

CONCLUSION

BGM complex improves the treatment outcome of adapalene 0.1% gel in patients with acne vulgaris. Overall, safety and local tolerance of BGM complex were good.

[Tanakan as a multimodal cytoprotective factor in general medicine (part II)]

The second section of the review provides an update of the data on mechanisms of action of a standardized extract of Ginkgo biloba EGb761® (tanakan) and its efficacy in treatment of depression, pain, complications of diabetes, Parkinson disease, tinnitus and dizziness, reproductive dysfunction. Updated data enable to use EGb761® (tanakan) as a highly-effective cytoprotective agent in treatment of cardiovascular, degenerative and metabolic diseases of the nervous system, inner ear disturbances (tinnitus), dysfunction of reproductive system as well as in prevention and treatment of stress-induced disorders.

Neuroprotective effects of bilobalide on cerebral ischemia and reperfusion injury are associated with inhibition of pro-inflammatory mediator production and down-regulation of JNK1/2 and p38 MAPK activation

BACKGROUND

Mitogen-activated protein kinase (MAPK) signaling pathways are implicated in inflammatory and apoptotic processes of cerebral ischemia and reperfusion (I/R) injury. Hence, MAPK pathways represent a promising therapeutic target. Exploring the full potential of inhibitors of MAPK pathways is a useful therapeutic strategy for ischemic stroke. Bilobalide, a predominant sesquiterpene trilactone constituent of Ginkgo biloba leaves, has been shown to exert powerful neuroprotective properties, which are closely related to both anti-inflammatory and anti-apoptotic pathways. We investigated the neuroprotective roles of bilobalide in the models of middle cerebral artery occlusion and reperfusion (MCAO/R) and oxygen-glucose deprivation and reoxygenation (OGD/R) of cerebral I/R injury. Moreover, we attempted to confirm the hypothesis that its protection effect is via modulation of pro-inflammatory mediators and MAPK pathways.

METHODS

Male Sprague-Dawley rats were subjected to MCAO for 2 h followed by reperfusion for 24 h. Bilobalide was administered intraperitoneally 60 min before induction of middle cerebral artery occlusion (MCAO). After reperfusion, neurological deficit scores, infarct volume, infarct weight, and brain edema were assessed. Ischemic penumbrae of the cerebral cortex were harvested to determine superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide, TNF-α, interleukin 1β (IL-1β), p-ERK1/2, p-JNK1/2, and p-p38 MAPK concentration. Similarly, the influence of bilobalide on the expression of nitric oxide, TNF-α, IL-1β, p-ERK1/2, p-JNK1/2, and p-p38 MAPK was also observed in an OGD/R in vitro model of I/R injury.

RESULTS

Pretreatment with bilobalide (5, 10 mg/kg) significantly decreased neurological deficit scores, infarct volume, infarct weight, brain edema, and concentrations of MDA, nitric oxide, TNF-α, IL-1β, and increased SOD activity. Furthermore, bilobalide (5, 10 mg/kg) pretreatment significantly down-regulated both p-JNK1/2 and p-p38 MAPK expression, whereas they had no effect on p-ERK1/2 expression in the ischemic penumbra. Supporting these observations in vivo, pretreatment with bilobalide (50, 100 μM) significantly down-regulated nitric oxide, TNF-α, IL-1β, p-JNK1/2, and p-p38 MAPK expression, but did not change p-ERK1/2 expression in rat cortical neurons after OGD/R injury.

CONCLUSIONS

These data indicate that the neuroprotective effects of bilobalide on cerebral I/R injury are associated with its inhibition of pro-inflammatory mediator production and down-regulation of JNK1/2 and p38 MAPK activation.