Spinosin, a C-Glucosylflavone, from Zizyphus jujuba var. spinosa Ameliorates Aβ1-42 Oligomer-Induced Memory Impairment in Mice

A Combination of Magnoflorine and Spinosin Improves the Antidepressant effects on CUMS Mouse Model

BACKGROUND

Depression is a common neuropsychiatric disease. As a famous traditional Chinese medicine with significant anti-depressive and sleep-promoting effects, Ziziphi Spinosae Semen (ZSS) has attracted the attention of many researchers. Although it is well known that Magnoflorine (MAG) and Spinosin (SPI) were the main active components isolated from ZSS, there is a lack of research on the combined treatment of depression with these two ingredients.

METHODS

The shaking bottle method was used to simulate the human environment for detecting the changes in oil-water partition coefficient before and after the drug combination. Cell viability was evaluated by the MTT assay. To establish a mouse model of depression and insomnia by CUMS method, and then to explore the effect of combined administration of MAG and SPI on depression in CUMS model by observing behavior and analyzing pharmacokinetics.

RESULTS

The change in LogP values affected the lipid solubility of MAG and increased the water solubility of SPI, allowing them to penetrate more easily through the blood-brain barrier into the brain. Compared with the model group, MAG-SPI with a concentration of 60 μM significantly increased cell survival rate. In both the TST and FST experiments, the mice showed a decrease in immobilization time. Pharmacokinetic results showed that the pharmacokinetic parameters, Cmax and AUC of MAG and SPI, were increased in the case of combination, which resulted in enhancement of their relative bioavailability and improvement of in vivo effects.

CONCLUSIONS

The present study demonstrated that a combination of MAG and SPI had a synergistic antidepressant effect in CUMS mouse model.

Natural compounds regulate the PI3K/Akt/GSK3β pathway in myocardial ischemia-reperfusion injury

The PI3K/Akt/GSK3β pathway is crucial in regulating cardiomyocyte growth and survival. It has been shown that activation of this pathway alleviates the negative impact of ischemia-reperfusion. Glycogen synthase kinase-3 (GSK3β) induces apoptosis through stimulation of transcription factors, and its phosphorylation has been suggested as a new therapeutic target for myocardial ischemia-reperfusion injury (MIRI). GSK3β regulatory role is mediated by the reperfusion injury salvage kinase (RISK) pathway, and its inhibition by Akt activation blocks mitochondrial permeability transition pore (mPTP) opening and enhances myocardial survival. The present article discusses the involvement of the PI3K/Akt/GSK3β pathway in cardioprotective effects of natural products against MIRI.Abbreviations: Akt: protein kinase B; AMPK: AMP-activated protein kinase; ATP: adenosine triphosphate; Bad: bcl2-associated agonist of cell death; Bax: bcl2-associated x protein; Bcl-2: B-cell lymphoma 2; CK-MB: Creatine kinase-MB; CRP: C-reactive-protein; cTnI: cardiac troponin I; EGCG: Epigallocatechin-3-gallate; Enos: endothelial nitric oxide synthase; ER: endoplasmic reticulum; ERK ½: extracellular signal‑regulated protein kinase ½; GSK3β: glycogen synthase kinase-3; GSRd: Ginsenoside Rd; GSH: glutathione; GSSG: glutathione disulfide; HO-1: heme oxygenase-1; HR: hypoxia/reoxygenation; HSYA: Hydroxysafflor Yellow A; ICAM-1: Intercellular Adhesion Molecule 1; IKK-b: IκB kinase; IL: interleukin; IPoC: Ischemic postconditioning; IRI: ischemia-reperfusion injury; JNK: c-Jun N-terminal kinase; Keap1: kelch-like ECH-associated protein- 1; LDH: lactate dehydrogenase; LVEDP: left ventricular end diastolic pressure; LVP: left ventricle pressure; LVSP: left ventricular systolic pressure; MAPK: mitogen-activated protein kinase; MDA: malondialdehyde; MIRI: myocardial ischemia-reperfusion injury; MnSOD: manganese superoxide dismutase; mPTP: mitochondrial permeability transition pore; mtHKII: mitochondria-bound hexokinase II; Nrf-1: nuclear respiratory factor 1; Nrf2: nuclear factor erythroid 2-related factor; NO: nitric oxide; PGC-1α: peroxisome proliferator‑activated receptor γ coactivator‑1α; PI3K: phosphoinositide 3-kinases; RISK: reperfusion injury salvage kinase; ROS: reactive oxygen species; RSV: Resveratrol; SOD: superoxide dismutase; TFAM: transcription factor A mitochondrial; TNF-α: tumor necrosis factor-alpha; VEGF-B: vascular endothelial growth factor B.

Efficacy of Kami Guibi-tang as an Add-On Therapy to Acetylcholinesterase Inhibitor for Cognitive Function in Mild Alzheimer's Disease: A Pilot Study

Background

Kami Guibi-tang (KGT), a traditional Korean herbal medicine is mainly used to treat insomnia and nervousness. Acetylcholinesterase inhibitors (AChEIs) are the main treatments for mild Alzheimer's disease (AD), a degenerative brain disease. However, currently no drug can fundamentally treat AD or reverse the advanced cognitive decline. This clinical study explored the efficacy and safety of adding KGT to AChEI for cognitive function in mild AD.

Methods

This was a pilot study for a larger randomized, double-blind, placebo-controlled trial. Participants between 55-90 years diagnosed with mild AD were recruited from Kyung Hee University Hospital at Gangdong, Seoul, Korea. They were randomized to receive either KGT or placebo for 24 weeks, in addition to their regular AChEI. The primary outcome was treatment efficacy, as assessed by the relative amount of change over the study period in total scores on the Dementia version of the Seoul Neuropsychological Screening Battery (SNSB-D). Changes in SNSB subscores were assessed as secondary outcomes. Safety parameters, including adverse events and abnormalities in blood tests, electrocardiograms, and brain magnetic resonance imaging were also monitored.

Results

Between March 2018 and November 2020, seven participants each in the KGT group and the placebo group completed the 24-week trial. There were no significant changes in SNSB-D total or subindex scores for either group (p = 0.69 and 0.63, respectively), and no significant differences were observed between them (p=0.71). No adverse events related to KGT were reported. We also compared and analyzed the results of a previous pilot study conducted on amnestic mild cognitive impairment (aMCI) using protocol of this study. The aMCI group showed a significant improvement in the total SNSB-D score, especially in the memory domain, compared to the mild AD group (p = 0.04 and 0.02, respectively). The Korean Mini-Mental State Exam and Korean Instrumental Activities of Daily Living scores also significantly improved in the aMCI group (p = 0.01 and 0.02, respectively).

Conclusions

Compared to placebo, adding KGT to AChEI did not significantly improve cognitive function in SNSB in patients with mild AD. We suggest that KGT would have a positive effect on patients with early stages of cognitive impairment such as aMCI. The findings could assist design larger, longer-term clinical trials of KGT use in elderly patients with mild AD. This study was registered in the Korean Clinical Trial Registry on December 26, 2017, with the CRIS approval number KCT0002904.

Dopamine D2 receptor agonist Bromocriptine ameliorates Aβ1-42-induced memory deficits and neuroinflammation in mice

Alzheimer's Disease (AD) is the most common neurodegenerative disease, which lacks disease-modifying therapeutics so far. Studies have shown that the dysfunction of the dopaminergic system is related to a variety of pathophysiology of AD, and the expression of Dopamine D2 receptor (DRD2) in the brains of AD patients and animal models is significantly downregulated, suggesting that DRD2 may represent a therapeutic target for AD. However, the strategy of targeting DRD2 for AD treatment still lacks some key experimental evidences. Here we show that DRD2 agonist Bromocriptine improved Aβ_1-42 induced neuroinflammation, neuronal apoptosis, and memory deficits in mice. For animal study, the mice have injected intracerebroventricularly (i.c.v.) with Aβ_1-42(410 pmol/5 μl) to induced AD cognitive deficit model (Mazzola et al., 2003; van der Stelt et al., 2006). After 7 days, Bromocriptine (2.5 mg/kg, 5 mg/kg and 10 mg/kg) or normal saline was administered intragastrically once a day for 30 days. Behavioral tests about the Y maze and Morris water maze in mice were initiated on the twenty-fourth day of drug administration for 7 days. In vivo and in vitro mechanism research revealed that Bromocriptine, via activating DRD2, promoted the recruitment of PP2A and JNK by scaffold protein β-arrestin 2, that repressed JNK-mediated transcription of proinflammatory cytokines and activation of NLRP3 inflammasome in microglia. Collectively, our findings suggest that Bromocriptine can ameliorate Aβ_1-42 induced neuroinflammation and memory deficits in mice through DRD2/β-arrestin 2/PP2A/JNK signaling axis, which provides an experimental basis for the development of Bromocriptine as a drug for AD.

Ginsenoside and Its Therapeutic Potential for Cognitive Impairment

Cognitive impairment (CI) is one of the major clinical features of many neurodegenerative diseases. It can be aging-related or even appear in non-central nerve system (CNS) diseases. CI has a wide spectrum that ranges from the cognitive complaint with normal screening tests to mild CI and, at its end, dementia. Ginsenosides, agents extracted from a key Chinese herbal medicine (ginseng), show great promise as a new therapeutic option for treating CI. This review covered both clinical trials and preclinical studies to summarize the possible mechanisms of how ginsenosides affect CI in different diseases. It shows that ginsenosides can modulate signaling pathways associated with oxidative stress, apoptosis, inflammation, synaptic plasticity, and neurogenesis. The involved signaling pathways mainly include the PI3K/Akt, CREB/BDNF, Keap1/Nrf2 signaling, and NF-κB/NLRP3 inflammasome pathways. We hope to provide a theoretical basis for the treatment of CI for related diseases by ginsenosides.

The pharmacology, pharmacokinetics, and toxicity of spinosin: A mini review

Spinosin, a natural flavone-C-glycoside that is mainly isolated from the seeds of Ziziphus jujuba Mill. var. spinosa. It exerts the effects to ameliorate the neurological disorders, such as hypnosis effects, improvement of cognitive function, sedation effects, and anxiolytic effects, as well as anti-melanogenic effect, cardioprotective effects, and anti-cancer activity. However, the insufficient basic research, unclear mechanisms, and poor bioavailability may limit the prospects of spinosin in clinical utilization. In this review, we comprehensively summarized the latest information on the pharmacology, pharmacokinetics, toxicity, and NMR characteristic of spinosin, to evaluate its potential therapeutic for clinical application, hoping to provide some rational perspective for the innovative agent development and usage of spinosin in future.

Spinosin ameliorates insulin resistance by suppressing reactive oxygen species-associated inflammation

Objectives

Spinosin is the predominant C-glycoside flavonoid derived from the seeds of Zizyphus jujuba var. Spinosa (Rhamnaceae). The present study aimed to investigate the effects of spinosin on insulin resistance (IR) in vascular endothelium.

Materials and Methods

The anti-IR effect of spinosin was evaluated in a high-fat diet (HFD) treated mice model. The effects of spinosin pretreatment on reactive oxygen species (ROS)-associated inflammation in Human umbilical vein endothelial cells (HUVEC) were evaluated by western blot analysis and reverse transcription-polymerase chain reaction. The effect of spinosin on insulin-mediated endothelium-dependent vasodilation of rat aortae was further evaluated.

Results

Spinosin at 20 mg/kg alleviates increased mice's body weight, fasting serum glucose, oral glucose tolerance, serum insulin, insulin resistance index, and serum lipid of HFD-treated mice. Spinosin at 20 μM suppressed ROS overproduction, and inhibited ROS-related HUVEC inflammation by inhibiting mRNA expression of tumor necrosis factor-α and interleukin-6. In addition, spinosin at 0.1 μM showed a vasodilation effect of isoprenaline-pretreated rat aortae and increased insulin-mediated NO production in endothelial cells. These effects were shown to be related to the spinosin regulating serine/tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) facilitated/phosphoinositide 3-kinase (PI3K) signaling.

Conclusion

Spinosin may ameliorate IR and ROS-associated inflammation, and increase endothelial NO production by mediating IRS-1/PI3K/endothelial nitric oxide synthase (eNOS) pathway.

Zizyphi Spinosae Semen: a natural herb resource for treating neurological disorders

Neurological disorders generally have the characteristics of occult onset and progressive development, which can do some serious damage to human body in the aging process. It is worth noting that traditional medicine can potentially prevent and treat such diseases. Zizyphi Spinosae Semen (ZSS), the seeds of Ziziphus jujuba var. spinosa it has a long clinical history for sleep regulation. In recent years, ZSS has been proved to exhibit various types of neuroprotective activity, such as sleep improvement, antidepressant, anti-anxiety, memory improvement and etc. It has become a popular natural product due to its many inherently available compounds that demonstrate medicinal and pharmacological importance. This paper reviews the main components and their metabolic transformation processes, highlights the various neurofunctional regulation activities and their mechanisms of ZSS, providing a theoretical basis for further research and clinical application of this natural medicine.

A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Phase IIb Clinical Study to Evaluate the Safety and Efficacy of DHP1401 in Patients with Mild to Moderate Alzheimer's Disease Treated with Donepezil: DHP1401 Randomized Trial in Mild to Moderate Alzheimer's Disease (DRAMA)

BACKGROUND

Preclinical studies in transgenic models of Alzheimer's disease (AD) suggest that DHP1401 has neuroprotective and memory-enhancing effects.

OBJECTIVE

To evaluate the efficacy and safety of DHP1401 in AD patients treated with donepezilMethods:Methods: In a double-blind study, patients with mild-to-moderate AD were randomized (1:1:1) to receive a twice daily total dose of 500 mg or 1000 mg DHP1401 or placebo for 24 weeks. Tolerability and safety were monitored at baseline and weeks 12 and 24.

RESULTS

total of 180 patients were randomized to Active 1 (500 mg: n = 62), Active 2 (1000 mg: n = 53), and control groups (n = 65) in 16 sites in Korea. There was no significant difference in the Alzheimer's Disease Assessment Scale (ADAS-cog) score, the primary efficacy endpoint, from baseline. However, in the subgroup with mild AD patients (MMSE, 20-26) who received the high dose of DHP1401 and the group that received donepezil 5 mg, the ADAS-cog scores improved. MMSE and K-TMT-e type B were significant in both active groups at week 24. The most frequently observed symptom was dizziness (2.78%), and the most commonly observed reactions were related to metabolism and nutrition disorders (5.00%). No remarkable adverse events were observed for 24 weeks.

CONCLUSION

Although the effectiveness of DHP1401 was not proved to be superior as the primary efficacy endpoint, the secondary endpoints, MMSE and K-TMT-e type B, showed significant beneficial effects. Also, the subgroups showed that ADAS-cog scores significantly were improved. DHP1401 could be proven beneficial for the AD treatment by further clinical trials.

Medicine-Food Herbs against Alzheimer’s Disease: A Review of Their Traditional Functional Features, Substance Basis, Clinical Practices and Mechanisms of Action

Alzheimer’s disease (AD) is a progressive, neurodegenerative disorder that currently has reached epidemic proportions among elderly populations around the world. In China, available traditional Chinese medicines (TCMs) that organically combine functional foods with medicinal values are named “Medicine Food Homology (MFH)”. In this review, we focused on MFH varieties for their traditional functional features, substance bases, clinical uses, and mechanisms of action (MOAs) for AD prevention and treatment. We consider the antiAD active constituents from MFH species, their effects on in vitro/in vivo AD models, and their drug targets and signal pathways by summing up the literature via a systematic electronic search (SciFinder, PubMed, and Web of Science). In this paper, several MFH plant sources are discussed in detail from in vitro/in vivo models and methods, to MOAs. We found that most of the MFH varieties exert neuroprotective effects and ameliorate cognitive impairments by inhibiting neuropathological signs (Aβ-induced toxicity, amyloid precursor protein, and phosphorylated Tau immunoreactivity), including anti-inflammation, antioxidative stress, antiautophagy, and antiapoptosis, etc. Indeed, some MFH substances and their related phytochemicals have a broad spectrum of activities, so they are superior to simple single-target drugs in treating chronic diseases. This review can provide significant guidance for people’s healthy lifestyles and drug development for AD prevention and treatment.

Kihito prevents corticosterone-induced brain dysfunctions in mice

Kihito (KIT; Gui Pi Tang) is a traditional herbal medicine that is used for treatment of neuropsychiatric disorders such as depression, anxiety, neurosis and insomnia in China and Japan. Recently, it has also been shown that KIT improves cognitive dysfunction in patients with Alzheimer's disease. In this study, to investigate the mechanisms underlying the effects of KIT on stress-induced brain dysfunctions such as a depressed state and memory impairment, we examined whether KIT prevents behavioral and neurophysiological abnormalities in mice treated chronically with corticosterone (CORT). CORT (40 mg/kg/day, s.c.) and KIT (1000 mg/kg/day, p.o.) were given to 7-week-old male ddY mice for 14 days. Twenty-four hours after the last treatment, depression-like behavior in the forced swim test, spatial memory in the Barnes maze test, cell survival and the number of new-born immature neurons, dendritic spine density and expression levels of mRNA for neurotrophic factors were analyzed. Depression-like behavior and spatial memory impairment were observed in CORT-treated mice without KIT treatment. Hippocampal cell survival, the number of hippocampal new-born immature neurons, hippocampal and accumbal dendritic spine density and mRNA levels for neurotrophic factors such as glial cell line-derived neurotrophic factor (GDNF) were decreased in CORT-treated mice without KIT treatment. KIT prevented CORT-induced depression-like behavior, spatial memory impairment, and decreases in hippocampal cell survival, the number of hippocampal new-born immature neurons, accumbal dendritic spine density and GDNF mRNA. KIT may ameliorate stress-induced brain dysfunctions via prevention of adverse effects of CORT on cell survival, new-born immature neurons, spine density and neurotrophic factors.

Metagenomic and phytochemical analyses of kefir water and its subchronic toxicity study in BALB/c mice

BACKGROUND

In recent years, researchers are interested in the discovery of active compounds from traditional remedies and natural sources, as they reveal higher therapeutic efficacies and improved toxicological profiles. Among the various traditional treatments that have been widely studied and explored for their potential therapeutic benefits, kefir, a fermented beverage, demonstrates a broad spectrum of pharmacological properties, including antioxidant, anti-inflammation, and healing activities. These health-promoting properties of kefir vary among the kefir cultures found at the different part of the world as different media and culture conditions are used for kefir maintenance and fermentation.

METHODS

This study investigated the microbial composition and readily found bioactive compounds in water kefir fermented in Malaysia using 16S rRNA microbiome and UHPLC sequencing approaches. The toxicity effects of the kefir water administration in BALB/c mice were analysed based on the mice survival, body weight index, biochemistry profile, and histopathological changes. The antioxidant activities were evaluated using SOD, FRAP, and NO assays.

RESULTS

The 16S rRNA amplicon sequencing revealed the most abundant species found in the water kefir was Lactobacillus hilgardii followed by Lactobacillus harbinensis, Acetobacter lovaniensis, Lactobacillus satsumensis, Acetobacter tropicalis, Lactobacillus zeae, and Oenococcus oeni. The UHPLC screening showed flavonoid and phenolic acid derivatives as the most important bioactive compounds present in kefir water which has been responsible for its antioxidant activities. Subchronic toxicity study showed no toxicological signs, behavioural changes, or adverse effects by administrating 10 mL/kg/day and 2.5 mL/kg/day kefir water to the mice. Antioxidants assays demonstrated enhanced SOD and FRAP activities and reduced NO level, especially in the brain and kidney samples.

CONCLUSIONS

This study will help to intensify the knowledge on the water kefir microbial composition, available phytochemicals and its toxicological and antioxidant effects on BALB/c mice since there are very limited studies on the water kefir grain fermented in Malaysia.

Effects of the fermented Zizyphus jujuba in the amyloid β25-35-induced Alzheimer's disease mouse model

BACKGROUD/OBJECTIVES

Alzheimer's disease (AD) is the most common cause of dementia in the elderly. Due to the increased incidence of dementia, there is a corresponding increase concerning the importance of AD. In this study, we investigated the protective effects conferred by Zizyphus jujuba (Zj) and Zizyphus jujuba fermented by yeast (Zj-Y), on cognitive impairment in an AD mouse model.

MATERIALS/METHODS

AD was induced by injecting amyloid beta_25-35 (Aβ_25-35) in ICR mice, and subsequently 200 mg/kg Zj or Zj-Y was administered daily for 14 days. The cognitive ability of AD mice was observed through behavioral experiments in T-maze, novel object recognition, and Morris water maze tests. We subsequently measured the levels of malondialdehyde (MDA), nitric oxide (NO), aspartate aminotransferase, and alanine aminotransferase in either tissues or serum.

RESULTS

In behavioral tests, deterioration was revealed in the short- and long-term learning and memory functions in the Aβ_25-35-injected control group compared to the normal group, indicating that Aβ_25-35 injection impairs cognitive functions. However, administration of Zj and Zj-Y improved cognitive function in mice, as compared to the Aβ_25-35-injected control mice. In addition, the Aβ_25-35 induced elevations of MDA and NO in the brain, kidney, and liver were suppressed after exposure to Zj and Zj-Y. Especially, Zj-Y showed stronger scavenging effect against MDA and NO, as compared to Zj.

CONCLUSIONS

Results of the present study indicate that Zj-Y exerts a protective effect on cognitive impairment and memory dysfunction, which is exerted by attenuating the oxidative stress induced by Aβ_25-35.

Identification of polyphenol from Ziziphi spinosae semen against human colon cancer cells and colitis-associated colorectal cancer in mice

Homology of medicine and food-zizyphi spinosi semen (ZSS) exhibits abundant pharmacological activities, such as sedation, hypnosis and anti-depression. In the present study, the water soluble polyphenols extracted from ZSS via the acid digestion method were named ZSSP, and exhibited significant anti-colorectal cancer (CRC) activity, characterized by restraining cell proliferation, promoting cell apoptosis and increasing chemo-sensitivity of CRC cells. The potential of ZSSP in vivo was further evaluated in an AOM/DSS-induced colitis-associated carcinogenesis (CAC) mouse model. Intriguingly, ZSSP diminished the number and volume of CAC polyps in mice in a dose-dependent manner, and effectively limited the damage of mice organs induced by AOM/DSS. The immunohistochemistry result showed that the elevated CRC early markers in CAC mice, such as COX-II, EMR1, and Ki67, were potently prevented by the ZSSP treatment. Further, the component in ZSSP with the anti-CRC activity was identified as spinosin by the macroporous resin of SP207 and RP-HPLC-MS/MS. Interestingly, during the extraction process, sodium ions were introduced forming spinosin·Na+, which had better water solubility and more remarkable anti-CRC activity than the spinosin. This study provides a new pharmacological property of spinosin derived from ZSS, inhibiting the growth of human CRC cells and colitis-associated CRC in mice, which indicates its potential use as a natural agent against CRC.

Identification of the absorptive constituents and their metabolites in vivo of Ziziphi Spinosae Semen by UPLC-ESI-Q-TOF-MS/MS

In this research, ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) was used for detection and identification of the absorptive constituents and their metabolites in rat plasma, urine and feces following oral administration of Ziziphi Spinosae Semen alcohol extract. After structure elucidation, a total of 12 compounds in rat plasma, comprising seven prototypes and five metabolites, 28 compounds in urine, comprising 17 prototypes and 11 metabolites, and 23 compounds in feces, comrpising 17 prototypes and six metabolites, have been tentatively identified by comparison with standard compounds and reference literature information. To the best of our knowledge, this is the first comprehensive and systematical metabolic study on the seed. Mostly importantly, we propose that gastric acid could convert jujubosides into an absorbable form of ebelin lactone oligosaccharides, which may be responsible for the low bioavailability and specific bioactivities of these compounds. Additionally, we deduced that the absorption site of ebelin lactone oligosaccharides is located in the stomach, and that the ebelin lactone form of jujubosides may be more suitable for absorption than its hydrolysis product. Our investigation will be helpful to narrow the scope for potentially active ingredients of the seed, and pave the way for determination of the pharmacological mechanism of the seed.

Green tea extract containing enhanced levels of epimerized catechins attenuates scopolamine-induced memory impairment in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Green tea has been used as a traditional medicine to control brain function and digestion. Recent works suggest that drinking green tea could prevent cognitive function impairment. During tea manufacturing processes, such as brewing and sterilization, green tea catechins are epimerized. However, the effects of heat-epimerized catechins on cognitive function are still unknown. To take this advantage, we developed a new green tea extract, high temperature processed-green tea extract (HTP-GTE), which has a similar catechin composition to green tea beverages.

AIM OF THE STUDY

This study aimed to investigate the effect of HTP-GTE on scopolamine-induced cognitive dysfunction and neuronal differentiation, and to elucidate its underlying mechanisms of action.

MATERIALS AND METHODS

The neuronal differentiation promoting effects of HTP-GTE in SH-SY5Y cells was assessed by evaluating neurite length and the expression level of synaptophysin. The DNA methylation status at the synaptophysin promoter was determined in differentiated SH-SY5Y cells and in the hippocampi of mice. HTP-GTE was administered for 10 days at doses of 30, 100 and 300 mg/kg (p.o.) to mice, and its effects on cognitive functions were measured by Y-maze and passive avoidance tests under scopolamine-induced cholinergic blockade state.

RESULTS

HTP-GTE induced neuronal differentiation and neurite outgrowth via the upregulation of synaptophysin gene expression. These beneficial effects of HTP-GTE resulted from reducing DNA methylation levels at the synaptophysin promoter via the suppression of DNMT1 activity. The administration of HTP-GTE ameliorated cognitive impairments in a scopolamine-treated mouse model.

CONCLUSIONS

These results suggest that HTP-GTE could alleviate cognitive impairment by regulating synaptophysin expression and DNA methylation levels. Taken together, HTP-GTE would be a promising treatment for the cognitive impairment observed in dysfunction of the cholinergic neurotransmitter system.

Spinosin Inhibits Aβ1-42 Production and Aggregation via Activating Nrf2/HO-1 Pathway

The present research work primarily investigated whether spinosin has the potential of improving the pathogenesis of Alzheimer’s disease (AD) driven by β-amyloid (Aβ) overproduction through impacting the procession of amyloid precursor protein (APP). Wild type mouse Neuro-2a cells (N2a/WT) and N2a stably expressing human APP695 (N2a/APP695) cells were treated with spinosin for 24 h. The levels of APP protein and secreted enzymes closely related to APP procession were examined by western blot analysis. Oxidative stress related proteins, such as nuclear factor-erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) were detected by immunofluorescence assay and western blot analysis, respectively. The intracellular reactive oxygen species (ROS) level was analyzed by flow cytometry, the levels of Aβ_1-42 were determined by ELISA kit, and Thioflavin T (ThT) assay was used to detect the effect of spinosin on Aβ_1-42 aggregation. The results showed that ROS induced the expression of ADAM10 and reduced the expression of BACE1, while spinosin inhibited ROS production by activating Nrf2 and up-regulating the expression of HO-1. Additionally, spinosin reduced Aβ_1-42 production by impacting the procession of APP. In addition, spinosin inhibited the aggregation of Aβ_1-42. In conclusion, spinosin reduced Aβ_1-42 production by activating the Nrf2/HO-1 pathway in N2a/WT and N2a/APP695 cells. Therefore, spinosin is expected to be a promising treatment of AD.

Spinosin Attenuates Alzheimer's Disease-Associated Synaptic Dysfunction via Regulation of Plasmin Activity

Hippocampal synaptic dysfunction is a hallmark of Alzheimer’s disease (AD). Many agents regulating hippocampal synaptic plasticity show an ameliorative effect on AD pathology, making them potential candidates for AD therapy. In the present study, we investigated spinosin as a regulating agent of synaptic plasticity in AD. Spinosin attenuated amyloid β (Aβ)-induced long-term potentiation (LTP) impairment, and improved plasmin activity and protein level in the hippocampi of 5XFAD mice, a transgenic AD mouse model. Moreover, the effect of spinosin on hippocampal LTP in 5XFAD mice was prevented by 6-aminocaproic acid, a plasmin inhibitor. These results suggest that spinosin improves synaptic function in the AD hippocampus by regulating plasmin activity.

Neuroprotective Polyphenols: A Modulatory Action on Neurotransmitter Pathways

BACKGROUND

Balance in neurotransmission is essential for the proper functioning of the nervous system and even a small, but prolonged disturbance, can induce the negative feedback mechanisms leading to various neuropathologies. Neurodegenerative and mood disorders such as Alzheimer's, Parkinson's or affective disorders are increasing medical and social problems. Among the wide spectrum of potentially destructive events, oxidative stress and disrupted metabolism of some neurotransmitters such as acetylcholine, GABA, glutamate, serotonin or dopamine appear to play a decisive role. Biologically active plant polyphenols have been shown to exert a positive impact on the function of the central nervous system by modulation of metabolism and the action of some neurotransmitters.

METHODS

Based on published research, the pharmacological activities of some naturally occurring polyphenols have been reviewed, with a focus on their potential therapeutic importance in the regulation of neurotransmitter systems.

RESULTS

Phytochemicals can be classified into several groups and most of them possess anticancer, antioxidative, anti-inflammatory and neuroprotective properties. They can also modulate the metabolism or action of some neurotransmitters and/or their receptors. Based on these properties, phytochemicals have been used in traditional medicine for ages, although it was focused mainly on treating symptoms. However, growing evidence indicates that polyphenols may also prevent or slow neurological diseases.

CONCLUSION

Phytochemicals seem to be less toxic than synthetic drugs and they can be a safer alternative for currently used preparations, which exert adverse side effects. The neuroprotective actions of some plant polyphenols in the regulation of neurotransmitters metabolism, functioning of neurotransmitters receptors and antioxidative defense have potential therapeutic applications in various neurodegenerative disorders.

Herbal medicine for psychiatric disorders: Psychopharmacology and neuroscience-based nomenclature

Objectives: Herbs are frequently and concurrently used with prescribed drugs by patients worldwide. While clinical trials have found some herbs to be as useful as standard psychiatric drugs, most clinicians are unaware of their pharmacological mechanisms.Methods: We searched English language and other language literature with English abstracts listed in PubMed website, supplemented by additional through Google Scholar's free academic paper abstract website for publications on herbs, focussing on their clinical use in mental disorders, their neurobiology and their pharmacology.Results: A major reason for herbs remaining outside of mainstream psychiatry is that the terminology and concepts in herbal medicine are not familiar to psychiatrists in general. Many publications regarding the use of herbal medicine for psychiatric disorders are deficient in details regarding diagnosis, criteria for response and the neurobiology details compared with publications on standard psychotropic drugs. Nomenclature for herbal medicine is usually confusing and is not conducive to an easy understanding of their mode of action in psychiatric disorders.Conclusions: The recent neuroscience-based nomenclature (NbN) for psychotropics methodology would be a logical application to herbal medicine in facilitating a better understanding of the use of herbal medicine in psychiatry.

Spinosin and 6'''‑Feruloylspinosin protect the heart against acute myocardial ischemia and reperfusion in rats

Investigating active compounds from Chinese herbal medicine that can rescue myocardial cells is a good approach to preserve cardiac function. Several herbal formulae that containing Semen Ziziphi Spinosae (SZS), also called Suanzaoren in Chinese, are clinically effective in the treatment of patients with acute myocardial infarction (AMI). The present study aimed to investigate the cardioprotective effects of spinosin and 6‴-feruloylspinosin, two flavonoid glycosides from SZS, in a rat model of myocardial ischemia and reperfusion. The left anterior descending artery (LAD) was occluded to induce myocardial ischemia. Spinosin or 6‴-feruloylspinosin (5 mg/kg) was intraperitoneally injected into rats 30 min before LAD ligation. The protein levels of myocardial enzymes in the serum, the extent of tissue injury and the rate of apoptosis were examined after AMI in rats with or without pretreatment with spinosin or 6‴-feruloylspinosin. Western blotting was performed to investigate the potential mechanisms underlying the function of these two flavonoid glycosides. The present results suggested that pretreatment with spinosin or 6‴-feruloylspinosin significantly attenuated myocardial tissue injury, and reduced myocardial enzyme release and cell apoptosis in AMI rats. In addition, spinosin treatment increased light chain 3B-II and 6‴-feruloylspinosin, and reduced p62, indicating that autophagy was promoted after drug treatments. Treatments of spinosin and 6‴-feruloylspinosin led to the reduction of glycogen synthase kinase-3β (GSK3β) phosphorylation at Tyr216, and the increase of peroxisome proliferator-activated receptor γ coactivator (PGC)-1α and its downstream signaling proteins, including nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and hemeoxygenase1 (HO-1). The present data suggested that SZS flavonoids could protect myocardial cells against acute heart ischemia-reperfusion, probably via the inhibition of GSK3β, which increased autophagy and the activity of the PGC-1α/Nrf2/HO-1 pathway.

Purification of spinosin from Ziziphi Spinosae Semen using macroporous resins followed by preparative high-performance liquid chromatography

As a well-known traditional Chinese medicine, Ziziphi Spinosae Semen has been used for treating anxiety and insomnia for a long time. Spinosin, the main active C-glycoside flavonoid in Ziziphi Spinosae Semen, has attracted much attention because of its many pharmacological activities including strong hypnotic effects, anxiolytic-like effects, and so on. In the present work, high-purity spinosin was separated from Ziziphi Spinosae Semen using the HPD-300 resin followed by preparative high-performance liquid chromatography. The adsorption kinetics curve of spinosin on the HPD-300 resin was studied and fitted well by the pseudo-second-order equation. The adsorption isotherms were also constructed and low temperature favored the adsorption reaction. The separation parameters were optimized using dynamic adsorption and desorption tests. After a one-run treatment with HPD-300 resin, the concentration of spinosin increased 11.8-fold from 0.99 to 11.7% with a recovery yield of 80.4%. Furthermore, the purity of spinosin could surpass above 98% after separation by preparative high-performance liquid chromatography and recrystallization with a recovery yield of 72.6%. The developed method was effective and suitable for the large-scale preparation of spinosin. Moreover, it was confirmed that HPD-300 resin could enable good selection for the enrichment of flavonoids from different plants.

Methanol extract of semen Ziziphi Spinosae attenuates ethanol withdrawal anxiety by improving neuropeptide signaling in the central amygdala

BACKGROUND

Ethanol withdrawal (EtOHW) anxiety is a crucial risk factor for alcoholic relapse. The neuropeptide nociceptin/orphanin FQ (N/OFQ) acts upon its receptor (NOP) to antagonize corticotropin-releasing factor (CRF) and elicit anxiolytic actions. Semen Ziziphi Spinosae (SZS), a prototypical hypnotic-sedative herb in Oriental medicine, exhibits anxiolytic effects during nicotine withdrawal by improving amygdaloid CRF/CRF1 receptor (CRFR1) signaling. Therefore, we evaluated the effects of SZS on EtOHW anxiety and the involvement of amygdaloid CRF/CRFR1 and N/OFQ/NOP pathways.

METHODS

Male Sprague Dawley rats received intraperitoneal injections of 2 g/kg EtOH (20% v/v) once daily for 28 d followed by a 3-d withdrawal. During EtOHW, the rats were given once-daily intragastric treatments of a methanol extract of SZS (MESZS, 60 or 180 mg/kg/d). Anxiety-like behaviors were measured with the open field (OF) and elevated plus maze (EPM) tests, and plasma corticosterone (CORT) levels were examined by an enzyme-linked immunosorbent assay. mRNA and protein expression levels of the neuropeptides and their receptors were determined by quantitative polymerase chain reaction and Western blot assays.

RESULTS

MESZS increased the distance traveled in the center zone of the OF and dose-dependently elongated the duration of staying in the center zone in EtOHW rats. MESZS increased both the number of entries into and the time spent in the open arms of the EPM by EtOHW rats. And, MESZS inhibited the over secretion of plasma CORT during EtOHW. EtOHW enhanced CRF and CRFR1 gene and protein expression in the central nucleus of the amygdala (CeA), which were inhibited by 180 mg/kg/d MESZS. EtOHW increased amygdaloid NOP mRNA and protein expression but spared N/OFQ mRNA expression, and 180 mg/kg/d MESZS further promoted these increases. Additionally, a post-MESZS intra-CeA infusion of either CRF or the selective NOP antagonist UFP-101 abolished the expected anxiolytic effect of 180 mg/kg/d MESZS.

CONCLUSIONS

These results suggest that MESZS ameliorates EtOHW anxiety by improving both CRF/CRFR1 and N/OFQ/NOP transmissions in the CeA.

Traditional Oriental Medicines and Alzheimer's Disease

Alzheimer’s disease (AD), which is the most major cause of dementia, is a progressive neurodegenerative disease that affects cognitive functions. Even though the prevalence of AD is continuously increasing, few drugs including cholinesterase inhibitors and N-methyl D-aspartate-receptor antagonists were approved to treat AD. Because the clinical trials of AD drugs with single targets, such as β-amyloid and tau, have failed, the development of multi-target drugs that ameliorate many of the symptoms of AD is needed. Thus, recent studies have investigated the effects and underlying mechanisms of herbal formulae consisting of various herb combinations used to treat AD. This review discusses the results of clinical and nonclinical studies of the therapeutic efficacy in AD and underlying mechanisms of the herbal formulae of traditional Oriental medicines and bioactive compounds of medicinal plants.

Safety Evaluation of a New Traditional Chinese Medical Formula, Ciji-Hua'ai-Baosheng II Formula, in Adult Rodent Models

Background

Ciji-Hua'ai-Baosheng II Formula (CHB-II-F) is a new traditional Chinese medical formula that has been shown to reduce toxicity and side effects of chemotherapy and increase the probability of cancer patient survival. Whether CHB-II-F is safe as an adjunctive therapy for cancer patients receiving chemotherapy has yet to be determined.

Purpose

To evaluate the acute and subchronic toxic effects of CHB-II-F in rodent models.

Methods

In acute toxicity test, 24 Kunming mice were divided into 2 groups: untreated control and CHB-II-F 1.05 g/mL (31.44 g/kg) treated group. Treatment was administered to the treated group 3 times a day for 14 days. The overall health, adverse reactions, and mortality rate were documented. In subchronic toxicity test, 96 Sprague-Dawley rats were divided into 4 groups: untreated control, high dose CHB-II-F (H) (26.20 g/kg), medium dose CHB-II-F (M) (13. 10 g/kg), and low dose CHB-II-F (L) (6.55 g/kg) [equal to 24.375 g (dried medicinal herb)/kg] treated groups. Treated groups were given the treatments once a day for 4 weeks. The overall health and mortality rate were recorded every day. Body weight and food consumption were measured once a week. Hematologic and biochemical parameters, organ weights, and histopathologic markers were analyzed after 4 weeks. An additional 2 weeks were given as the treatment recovery period before end-point euthanization, and biochemical analyses were performed.

Results

The maximum tolerated dose (MTD) of CHB-II-F on mice was found to be 94.31 g/kg [equal to 351 g (dried medicinal herb)/kg], which is 108 times the human adult dose. In the acute toxicity test, administration of CHB-II-F 31.44 g/kg showed no adverse effect and did not cause mortality. In the subchronic toxicity test, after 4 weeks of treatment, compared to the controls, total cholesterol (TCHO) level, cardiac and splenic indexes, body weights of female rats, and mean corpuscular hemoglobin concentration (MCHC) in the CHB-II-F (H) group were significantly increased; triglyceride (TG) in the CHB-II-F (M) group and liver and splenic indexes in the CHB-II-F (L) group were increased. After the two-week recovery period, biofluid analyses, food consumption, and histopathologic examinations showed no abnormalities.

Conclusion

Administration of CHB-II-F had no obvious adverse effect on the overall health of rodent models. A daily maximum dose of less than 94.31 g/kg or 6.55 g/kg CHB-II-F for 4 continuous weeks was considered safe.

Neuroprotective Effects of Spinosin on Recovery of Learning and Memory in a Mouse Model of Alzheimer's Disease

Previous studies have shown that spinosin was implicated in the modulation of sedation and hypnosis, while its effects on learning and memory deficits were rarely reported. The aim of this study is to investigate the effects of spinosin on the improvement of cognitive impairment in model mice with Alzheimer’s disease (AD) induced by Aβ_1–42 and determine the underlying mechanism. Spontaneous locomotion assessment and Morris water maze test were performed to investigate the impact of spinosin on behavioral activities, and the pathological changes were assayed by biochemical analyses and histological assay. After 7 days of intracerebroventricular (ICV) administration of spinosin (100 µg/kg/day), the cognitive impairment of mice induced by Aβ_1–42 was significantly attenuated. Moreover, spinosin treatment effectively decreased the level of malondialdehyde (MDA) and Aβ_1–42 accumulation in hippocampus. Aβ_1–42 induced alterations in the expression of brain derived neurotrophic factor (BDNF) and B-cell lymphoma-2 (Bcl-2), as well as inflammatory response in brain were also reversed by spinosin treatment. These results indicated that the ameliorating effect of spinosin on cognitive impairment might be mediated through the regulation of oxidative stress, inflammatory process, apoptotic program and neurotrophic factor expression, suggesting that spinosin might be beneficial to treat learning and memory deficits in patients with AD via multi-targets.

Phytochemicals and cognitive health: Are flavonoids doing the trick?

Flavonoids constitute a large group of polyphenolic compounds with numerous effects on behaviour and cognition. These effects vary from learning and memory enhancement to an improvement of general cognition. Furthermore, flavonoids have been implicated in a) neuronal proliferation and survival, by acting on a variety of cellular signalling cascades, including the ERK/CREB/BDNF and PI3K/Akt pathway, b) oxidative stress reduction and c) relief from Alzheimer's disease-type symptoms. From an electrophysiological aspect, they promote long term potentiation in the hippocampus, supporting the hypothesis of synaptic plasticity mediation. Together, these actions reveal a neuroprotective effect of flavonoid compounds in the brain. Therefore, flavonoid intake could be a potential clinical direction for prevention and/or attenuation of cognitive decline deterioration which accompanies various brain disorders. The purpose of the current review paper was to summarise all these effects on cognition, describe the possible pathways via which they may act on a cellular level and provide a better picture for future research towards this direction.

7-Deoxy-trans-dihydronarciclasine Reduces β-Amyloid and Ameliorates Memory Impairment in a Transgenic Model of Alzheimer's Disease

The critical pathological feature of Alzheimer's disease (AD) is the accumulation of β-amyloid (Aβ), the main constituent of amyloid plaques. β-amyloid precursor protein (APP) undergoes amyloidogenic cleavage by β- and γ-secretase generating Aβ at endosomes or non-amyloidogenic processing by α-secretase precluding the production of Aβ at the plasma membrane. Recently, several natural products have been widely researched on the prevention of Aβ accumulation for AD treatment. We previously reported that Lycoris chejuensis K. Tae et S. Ko (CJ), which originated from Jeju Island in Korea, improved the disrupted memory functions and reduced Aβ production in vivo. Here, we further explored the effect of its active component, 7-deoxy-trans-dihydronarciclasine (coded as E144), on Aβ generation and the underlying mechanism. Our results showed that E144 reduced the level of APP, especially its mature form, in HeLa cells overexpressing human APP with the Swedish mutation. Concomitantly, E144 decreased the levels of Aβ, sAPPβ, sAPPα, and C-terminal fragment. In addition, administration of E144 normalized the behavioral deficits in Tg2576 mice, an APP transgenic mouse model of AD. E144 also decreased the Aβ and APP levels in the cerebral cortex of Tg2576 mice. Thus, we propose that E144 could be a potential drug candidate for an anti-amyloid disease-modifying AD therapy.

The memory ameliorating effects of DHP1402, an herbal mixture, on cholinergic blockade-induced cognitive dysfunction in mice

ETHNOPHARMACOLOGICAL RELEVANCE

The seeds of Ziziphus jujuba var. spinosa (Bunge) Hu ex H.F Chow (Rhamnaceae) and the roots of Codonopsis lanceolata (Siedbold & Zucc.) Benth. & Hook. f ex Trautv. (Campanulaceae), contained in the DHP1402, have long been used for treating dementia or hypomnesia as folk medicine.

AIM OF THE STUDY

It has been reported that Z. jujuba var. spinosa and C. lanceolata are effective in improving cognitive function, but via different mechanisms. Therefore, in the present study, we evaluated the synergistic effects of Z. jujuba var. spinosa and C. lanceolata on scopolamine-induced memory impairment.

MATERIALS AND METHODS

Scopolamine, a cholinergic muscarinic receptor antagonist, was used to induce cognitive dysfunction. We employed several behavioral tasks to estimate the synergistic effect of the seeds of Z. jujuba var. spinosa and the roots of C. lanceolata. In addition, we introduced the Western blotting, the antagonism passive avoidance task to investigate a synergistic effect of an herbal formulation.

RESULTS

Synergistic effects of a combination of Z. jujuba var. spinosa and C. lanceolata at a 5:1 ratio [(w/w), DHP1402] were observed against cognitive dysfunction in the passive avoidance and Y-maze tasks. DHP1402 also ameliorated memory deficits in a dose-dependent manner in these behavioral tasks, as well as in the Morris water maze task. According to the Western blot results, the phosphorylation levels of protein kinase A (PKA), extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB) in the hippocampus were also increased in a synergistic manner after the administration of DHP1402. In addition, we found that the effects of DHP1402 on cognitive function were mediated by N-methyl-D-aspartate (NMDA) receptor signalling, based on the antagonism studies. Furthermore, we found that DHP1402 has inhibitory activity against acetylcholinesterase (AChE).

CONCLUSION

DHP1402 attenuates cholinergic blockade-induced cognitive dysfunction through NMDA receptor modulation, PKA-ERK-CREB pathway activation, and AChE inhibition. Therefore, DHP1402 could be a candidate for alleviating cognitive dysfunction.

Ziziphus spina-christi leaf extract pretreatment inhibits liver and spleen injury in a mouse model of sepsis via anti-oxidant and anti-inflammatory effects

Sepsis is a systemic response to infection that can result in acute hepatic and splenic damage. Ziziphus spina-christi (L.) is a wild tree used as a medicinal plant by ancient Egyptians. However, little is known about the mechanism underlying its effects on sepsis. The current study investigated the protective effects of a Z. spina-christi leaf extract (ZSCLE) on liver and spleen damage in a male C57BL/6 mouse model of sepsis, induced by cecal ligation and puncture (CLP). Prior to CLP, ZSCLE was administered daily for five consecutive days via oral gavage at doses of 100, 200, or 300 mg/kg. The mice were euthanized 9 h after CLP, and oxidative stress markers were measured (myeloperoxidase, lipid peroxidation, nitric oxide, and reduced glutathione). In addition, we investigated histological changes, anti-oxidant enzyme activities (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase), cytokine levels, protein expression of nuclear factor-κB and inducible nitric oxide synthase (iNOS), and mRNA levels of mitogen-activated protein kinase (8, 9, and 14), iNOS, tumor necrosis factor-α, and interleukin-1β. Our results indicated that ZSCLE significantly and dose-dependently inhibited sepsis-induced liver and spleen injury. These results suggest that ZSCLE could provide a therapeutic agent for sepsis by inducing anti-inflammatory and anti-oxidant effects.

Ethanol extract of the seed of Zizyphus jujuba var. spinosa potentiates hippocampal synaptic transmission through mitogen-activated protein kinase, adenylyl cyclase, and protein kinase A pathways

ETHNOPHARMACOLOGICAL RELEVANCE

As the seed of Zizyphus jujuba var. spinosa (Bunge) Hu ex H.F. Chow (Rhamnaceae) has been used to sleep disturbances in traditional Chinese and Korean medicine, many previous studies have focused on its sedative effect.

AIM OF THE STUDY

Recently, we reported the neuroprotective effect of the effect of Z. jujuba var. spinosa. However, its effects on synaptic function have not yet been studied. In this project, we examined the action of ethanol extract of the seed of Z. jujuba var. spinosa (DHP1401) on synaptic transmission in the hippocampus.

MATERIALS AND METHODS

To investigate the effects of DHP1401, field recordings were conducted using hippocampal slices (400µm). Object recognition test was introduced to examine whether DHP1401 affect normal recognition memory.

RESULTS

DHP1401 (50μg/ml) induced a significant increase in synaptic activity in Shaffer collateral pathway in a concentration-dependent manner. This increase of synaptic responses was blocked by NBQX, a broad spectrum α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist, but not IEM-1460, a Ca²⁺-permeable AMPAR blocker. Moreover, U0126, a mitogen-activated protein kinase inhibitor, SQ22536, an adenylyl cyclase inhibitor, and PKI, a protein kinase A inhibitor, blocked DHP1401-induced increase in synaptic transmission. Finally, DHP1401 facilitated object recognition memory.

CONCLUSIONS

These results suggest that DHP1401 increase synaptic transmission through increase of synaptic AMPAR transmission via MAPK, AC and PAK.

White Ginseng Protects Mouse Hippocampal Cells Against Amyloid-Beta Oligomer Toxicity

Amyloid-beta oligomer (AβO) is a soluble oligomer form of the Aβ peptide and the most potent amyloid-beta form that induces neuronal damage in Alzheimer's disease. We investigated the effect of dried white ginseng extract (WGE) on neuronal cell damage and memory impairment in intrahippocampal AβO (10 μM)-injected mice. Mice were treated with WGE (100 and 500 mg/kg/day, p.o.) for 12 days after surgery. WGE improved memory impairment by inhibiting hippocampal cell death caused by AβO. In addition, AβO-injected mice treated with WGE showed restoration of reduced synaptophysin and choline acetyltransferase intensity and lower levels of ionized calcium-binding adaptor molecule 1 in the hippocampus compared with those of vehicle-treated controls. These results suggest that WGE reverses memory impairment in Alzheimer's disease by attenuating neuronal damage and neuroinflammation in the AβO-injected mouse hippocampus. Copyright © 2017 John Wiley & Sons, Ltd.

Cassia obtusifolia seed ameliorates amyloid β-induced synaptic dysfunction through anti-inflammatory and Akt/GSK-3β pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Tea infused with the seed of Cassia obtusifolia has been traditionally used as an herbal remedy for liver, eye, and acute inflammatory diseases. Recent pharmacological reports have indicated that Cassiae semen has neuroprotective effects, attributable to its anti-inflammatory actions, in ischemic stroke and Parkinson's disease models.

AIM OF THE STUDY

Previously, the ethanol extract of C. obtusifolia seeds (COE) was reported to have memory enhancing properties. However, the effects of COE in an Alzheimer's disease (AD) model are currently unknown. In this study, we investigated the effect(s) of COE on aberrant synaptic plasticity and memory impairment induced by amyloid β (Aβ), a key toxic component found in the AD brain.

MATERIALS AND METHODS

To determine the effect of COE on Aβ-induced aberrant synaptic plasticity, we used acute mouse hippocampal slices and delivered theta burst stimulation to induce long-term potentiation (LTP). Western blots were used to detect Aβ- and/or COE-induced changes in signaling proteins. The novel object location recognition test was conducted to determine the effect of COE on Aβ-induced recognition memory impairment.

RESULTS

COE was found to ameliorate Aβ-induced LTP impairment in the acute hippocampal slices. Glycogen synthase kinase-3β (GSK-3β), a key molecule in LTP impairment, was activated by Aβ. However, this process was inhibited by COE via Akt signaling. Moreover, COE was found to attenuate Aβ-induced microglia, inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX) activation. In the in vivo studies performed, COE ameliorated the Aβ-induced object recognition memory impairment.

CONCLUSION

These results suggest that COE exhibits neuroprotective activities against Aβ-induced brain disorders.