Bangle (Zingiber purpureum) Improves Spatial Learning, Reduces Deficits in Memory, and Promotes Neurogenesis in the Dentate Gyrus of Senescence-Accelerated Mouse P8

Transcriptome analysis of PC12 cells reveals that trans-banglene upregulates RT1-CE1 and downregulates abca1 in the neurotrophic pathway

Trans(t)-banglene and cis(c)-banglene possess neurotrophin-like activity in rat neurons. However, the molecular mechanisms underlying t-banglene-induced neurotrophic activity in rat and human neurons remain unclear. Here, we performed transcriptome analysis in PC12 cells, a rat adrenal gland pheochromocytoma cell line treated with t-banglene, using comprehensive RNA sequencing. The differentially expressed gene analysis of the sequencing data revealed that the expression of RT1 class I, locus CE1 (RT1-CE1) was upregulated, and that of ATP binding cassette subfamily A member 1 (abca1), myosin light chain 6, and hippocampus abundant transcript 1 was downregulated in t-banglene-treated PC12 cells, with statistically significant differences. We also confirmed the RT1-CE1 upregulation and abca1 downregulation in t-banglene-treated PC12 cells by reverse transcription quantitative real-time polymerase chain reaction. RT1-CEl is a major histocompatibility complex class I (MHCI) protein. ABCAl is a major cholesterol transporter that regulates efflux of intracellular cholesterol and phospholipids. Thus, our results suggest an exciting link between MHCI, cholesterol regulation, and neural development.

Metabolite Profiling of Javanese Ginger Zingiber purpureum and Identification of Antiseizure Metabolites via a Low-Cost Open-Source Zebrafish Bioassay-Guided Isolation

The rhizomes of Zingiber purpureum, "Bangle", were investigated for its antiseizure properties using a streamlined and cost-effective zebrafish screening strategy and a mouse epilepsy assay. Its hexane extract demonstrated strong antiseizure activity in zebrafish epilepsy assay and was, therefore, selected for bioactivity-guided fractionation. Twelve compounds (1-12) were isolated, and two bioactive phenylbutenoids, trans- (11) and cis-banglene (12), reduced up to 70% of pentylenetetrazole (PTZ)-induced seizures. These compounds showed moderate activity against PTZ-induced seizures in a mouse epilepsy assay. To understand the specificity of Z. purpureum active compounds, its chemical profile was compared to that of Z. officinale. Their composition was assessed by differential metabolite profiling visualized by a molecular network, which revealed only vanillin derivatives and terpenoids as common metabolites and gave a comprehensive view of Z. purpureum composition. This study demonstrates the efficacy of a streamlined zebrafish epilepsy assay, which is therefore suitable for routine screening in phytochemistry laboratories.

Indonesian Ginger (Bangle) Extract Promotes Neurogenesis of Human Neural Stem Cells through WNT Pathway Activation

Indonesian ginger (Zingiber purpureum Rosc.), also known as Bangle, exhibits neurotrophic effects on cultured murine cortical neurons and in the adult mouse brain, but the underlying mechanisms remain unknown. Here, using human fetal neural stem cells (hfNSCs) as a model system for in vitro human neurogenesis, we show that Bangle extracts activate canonical WNT/β-catenin signaling. Bangle extract-treatment of hfNSCs not only promoted neuronal differentiation, but also accelerated neurite outgrowth from immature neurons. Furthermore, Bangle extracts induced expression of neurogenic genes and WNT signaling-target genes, and facilitated the accumulation of β-catenin in nuclei of hfNSC. Interestingly, altered histone modifications were also observed in Bangle-treated hfNSCs. Together, these findings demonstrate that Bangle contributes to hfNSC neurogenesis by WNT pathway and epigenetic regulation.

Safety Assessment of Bangle (Zingiber purpureum Rosc.) Rhizome Extract: Acute and Chronic Studies in Rats and Clinical Studies in Human

Bangle (Zingiber purpureum Rosc.) rhizome extract (BRE) contains phenylbutenoid dimers (banglenes), which exert neurotrophic effects and possess the potential capability to regenerate hippocampal neurons in mice. The acute and chronic oral toxicities of BRE powder were evaluated in Sprague-Dawley rats. A dose of BRE powder was estimated to be higher than 2000 mg/kg containing BRE 534 mg/kg as minimum lethal dose in a single-dose oral toxicity study. The no-observed-adverse-effect-level for the BRE powder was 1000 mg/kg/day (BRE 267 mg/kg) in the 90 day oral toxicity study. Four week clinical studies of BRE tablets in humans suggested that the ingestion of BRE tablets within 850 mg/man/day (BRE 227 mg/man/day) was safe for at least 1 month and in a usual manner. The C _max, t _max, and AUC of cis- and trans-(E)-3-(3,4-dimethoxyphenyl)-4-[(E)-3,4-dimethoxystyryl]cyclohex-1-enes (c- and t-banglenes) were calculated after the ingestion of BRE tablets (BRE 227 mg) and were 17.73 and 22.61 ng/mL, 1.8 and 1.8 h, and 71.47 and 95.53 ng/mL/h, respectively.

Glehnia littoralis Extract Promotes Neurogenesis in the Hippocampal Dentate Gyrus of the Adult Mouse through Increasing Expressions of Brain-Derived Neurotrophic Factor and Tropomyosin-Related Kinase B

Background:

Glehnia littoralis has been used for traditional Asian medicine, which has diverse therapeutic activities. However, studies regarding neurogenic effects of G. littoralis have not yet been considered. Therefore, in this study, we examined effects of G. littoralis extract on cell proliferation, neuroblast differentiation, and the maturation of newborn neurons in the hippocampus of adult mice.

Methods:

A total of 39 male ICR mice (12 weeks old) were randomly assigned to vehicle-treated and 100 and 200 mg/kg G. littoralis extract-treated groups (n = 13 in each group). Vehicle and G. littoralis extract were orally administrated for 28 days. To examine neurogenic effects of G. littoralis extract, we performed immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU, an indicator for cell proliferation) and doublecortin (DCX, an immature neuronal marker) and double immunofluorescence staining for BrdU and neuronal nuclear antigen (NeuN, a mature neuronal marker). In addition, we examined expressional changes of brain-derived neurotrophic factor (BDNF) and its major receptor tropomyosin-related kinase B (TrkB) using Western blotting analysis.

Results:

Treatment with 200 mg/kg, not 100 mg/kg, significantly increased number of BrdU-immunoreactive (⁺) and DCX⁺ cells (48.0 ± 3.1 and 72.0 ± 3.8 cells/section, respectively) in the subgranular zone (SGZ) of the dentate gyrus (DG) and BrdU⁺/NeuN⁺ cells (17.0 ± 1.5 cells/section) in the granule cell layer as well as in the SGZ. In addition, protein levels of BDNF and TrkB (about 232% and 244% of the vehicle-treated group, respectively) were significantly increased in the DG of the mice treated with 200 mg/kg of G. littoralis extract.

Conclusion:

G. littoralis extract promots cell proliferation, neuroblast differentiation, and neuronal maturation in the hippocampal DG, and neurogenic effects might be closely related to increases of BDNF and TrkB proteins by G. littoralis extract treatment.

Application of Natural Ingredients to Preventive Medicine

The super-aging society in Japan is currently experiencing growing demand for treatments that improve health and longevity. To develop new high-functional foods and search for pharmaceutical candidates among foods and natural products, it is necessary to promote organic collaboration among researchers in pharmacy, medicine, nutrition, and other fields to encourage joint utilization of their technologies. Recently, attempts have been made to use numerous foods and natural products to prevent or treat diseases based on scientific evidence. We have been endeavoring to develop preventive medicines from foods and natural ingredients by engaging in relevant activities such as screening these substances to determine the structures of their effective ingredients, verifying pharmacological activities, and conducting clinical trials. In this study, the effectiveness of Goishi tea (postfermented tea) and Flos Lonicerae (Japanese honeysuckle) for metabolic syndrome and hepatic disorders, respectively, was explored. Multicomponent foods and natural ingredients have diverse effects produced by the actions of individual components as well as the interactions among different components. Additionally, when using natural ingredients and similar materials, it is necessary to consider the different extraction efficiencies of various methods and their absorption, deposition, metabolism, and excretion after consumption. The influence of intestinal bacteria and other factors is also critical. In our study, the administration of Goishi tea and Flos Lonicerae in animal models of disease demonstrated high functionality. Based on these findings, we plan to conduct further investigations, including clinical studies in human participants, focusing on the potential usefulness of Goishi tea and Flos Lonicerae as functional foods.

Studies on Extraction Conditions to Increase the Content of Neurotrophic Compounds in the Bangle (Zingiber purpureum) Extract

To develop the Javanese ginger Bangle ( Zingiber purpureum), which contains neurotrophic phenylbutenoid compounds named banglenes 1 and 2, as a functional food additive for protection of neurodegenerative disease, we investigated conversion method from 3 to 1 and 2 under practical conditions available in food processing steps. After several trials, we found that dimerization of 3 proceeded smoothly under refluxing EtOH/H2O (1/3) in the presence of ubiquinone (0.1 eq) in sealed tube, giving rise to 1 and 2 in 54% yield. When this condition was applied for 70% EtOH extract of bangle, content of 1 and 2 in the extract was increased 2-fold by 2.1%.