Anti-amnesic effect of Chong-Myung-Tang on scopolamine-induced memory impairments in mice

Therapeutic Potential of Active Components from Acorus gramineus and Acorus tatarinowii in Neurological Disorders and Their Application in Korean Medicine

Neurological disorders represent a substantial healthcare burden worldwide due to population aging. Acorus gramineus Solander (AG) and Acorus tatarinowii Schott (AT), whose major component is asarone, have been shown to be effective in neurological disorders. This review summarized current information from preclinical and clinical studies regarding the effects of extracts and active components of AG and AT (e.g., α-asarone and β-asarone) on neurological disorders and biomedical targets, as well as the mechanisms involved. Databases, including PubMed, Embase, and RISS, were searched using the following keywords: asarone, AG, AT, and neurological disorders, including Alzheimer's disease, Parkinson's disease, depression and anxiety, epilepsy, and stroke. Meta-analyses and reviews were excluded. A total of 873 studies were collected. A total of 89 studies were selected after eliminating studies that did not meet the inclusion criteria. Research on neurological disorders widely reported that extracts or active components of AG and AT showed therapeutic efficacy in treating neurological disorders. These components also possessed a wide array of neuroprotective effects, including reduction of pathogenic protein aggregates, antiapoptotic activity, modulation of autophagy, anti-inflammatory and antioxidant activities, regulation of neurotransmitters, activation of neurogenesis, and stimulation of neurotrophic factors. Most of the included studies were preclinical studies that used in vitro and in vivo models, and only a few clinical studies have been performed. Therefore, this review summarizes the current knowledge on AG and AT therapeutic effects as a basis for further clinical studies, and clinical trials are required before these findings can be applied to human neurological disorders.

East Asian Herbal Medicine for the Treatment of Children with Attention Deficit Hyperactivity Disorder: A Systematic Review and Meta-analysis

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a mental illness that can place a significant burden on individuals, their families, and society. East Asian Herbal Medicine (EAHM) has long been used in East Asian nations to treat mental illness in children. Nevertheless, the evidence for the effectiveness of EAHM for the treatment of ADHD is insufficient. A systematic review was performed to examine the effectiveness and safety. In addition, research on core herbal combinations was also conducted to help clinicians in their prescription selection.

MATERIALS AND METHODS

This systematic review and meta-analysis were prepared according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The following databases were searched: 4 English databases (PubMed, Cochrane Library, Cumulative Index to Nursing & Allied Health Literature (CINAHL), EMBASE), 4 Korean databases (Korean Studies Information Service System (KISS), Research Information Service System (RISS), Oriental Medicine Advanced Searching Integrated System (OASIS), Korea Citation Index (KCI)), 2 Chinese databases (Chinese National Knowledge Infrastructure Database (CNKI), Wanfang Data), and 1 Japanese database (CiNii) database. The publication bias was evaluated using funnel plots. GRADE pro was used to evaluate the evidence of the study. The core herb combination of EAHM used in this study was revealed using apriori algorithm-based association rule mining.

RESULTS

This review assessed 42 studies that evaluated 3484 children and adolescents. In meta-analysis, EAHM monotherapy had a similar clinical efficacy rate to conventional medicine (CM) (n = 2166; random effects RR 1.09, 95% CI 1.05 to 1.13; heterogeneity χ2= 25.08, df = 23, p = 0.35, I²=8%). EAHM-combined therapy showed a better clinical efficacy rate than when conventional therapy was used alone (n = 746; fixed effects RR 1.19, 95% CI 1.12 to 1.26; heterogeneity χ2= 11.80, df = 9, p = 0.22, I²=24%). For adverse events, EAHM had a lower incidence than conventional therapy. In GRADE pro, each outcome varied from moderate to very low quality. The constituents of the herb combinations with consistent association rules were Fossilia Ossis Mastodi, Polygalae Radix, and Acori Graminei Rhizoma.

CONCLUSION

EAHM monotherapy has similar effects to CM but with fewer side effects. Hence, it will be helpful for children with ADHD suffering from the side effects of CM. EAHM-combined therapy has a better effect than conventional therapy. Accordingly, it will be useful for children with ADHD who do not respond to treatment with conventional therapy. Nevertheless, more well-designed studies will be needed to confirm this in the future.

Core prescription pattern of Chinese herbal medicine for depressive disorders in Taiwan: a nationwide population-based study

Background

Depressive disorders (DD) affect not only mood and behavior but also various physical functions. Traditional Chinese medicine (TCM) has been shown to have some benefits in treating DD. However, one formula or one single herb might be not show high efficacy when used to treat depression. Thus, this study aimed to examine the core prescription pattern of Chinese herbal medicine (CHM) among patients with DD in Taiwan as a reference for related research and clinical applications.

Methods

All patients, who had been diagnosed with major depressive disorder or minor depression or dysthymia without any other baseline diseases and had at least one CHM outpatient clinical visit from 2002 to 2011, were extracted from three randomly sampled cohorts, namely the 2000, 2005 and 2010 cohorts of the National Health Insurance Research Database (NHIRD) of Taiwan. The collected data was analyzed to explore the patterns of herbal products.

Results

There were 197,146 patients with a diagnosis of DD and of these 1806 subjects had only a diagnosis of DD and utilized CHM. The most common formula was Gan-Mai-Da-Zao-Tang (12.19%), while Suan-Zao-Ren (3.99%) was the most commonly prescribed single herb. The core pattern of prescriptions consisted of a combination of Gan-Mai-Da-Zao-Tang, Jia-Wei-Xiao-Yao-San, Chai-Hu-Jia-Long-Gu-Mu-Li-Tang, He-Huan-Pi, Yuan-Zhi and Shi-Chang-Pu.

Conclusions

This study describes the CHM core prescription pattern used to treat patients in Taiwan with DD and it is a potential candidate for study in future pharmacological or clinical trials targeting DD.

Extracts or Active Components from Acorus gramineus Aiton for Cognitive Function Impairment: Preclinical Evidence and Possible Mechanisms

Extracts or active components from Acorus gramineus Aiton (EAAGA) have been clinically used for cognition impairment more than hundreds of years and are still used in modern times in China and elsewhere worldwide. Previous studies reported that EAAGA improves cognition impairment in animal models. Here, we conducted a preclinical systematic review to assess the current evidence of EAAGA for cognition impairment. We searched 7 databases up until June 2019. Methodological quality for each included studies was accessed according to the CAMARADES 10-item checklist. The primary outcome measures were neurobehavioral function scores evaluated by the Morris water maze test, electrical Y-maze test, step-down test, radial eight-arm maze test, and step-through test. The secondary outcome measures were mechanisms of EAAGA for cognition function. Finally, 34 studies involving 1431 animals were identified. The quality score of studies range from 1 to 6, and the median was 3.32. Compared with controls, the results of the meta-analysis indicated EAAGA exerted a significant effect in decreasing the escape latency and error times and in increasing the length of time spent in the platform quadrant and the number of platform crossings representing learning ability and memory function (all P < 0.01). The possible mechanisms of EAAGA are largely through anti-inflammatory, antioxidant, antiapoptosis activities, inhibition of neurotoxicity, regulating synaptic plasticity, protecting cerebrovascular, stimulating cholinergic system, and suppressing astrocyte activation. In conclusion, EAAGA exert potential neuroprotective effects in experimental cognition impairment, and EAAGA could be a candidate for cognition impairment treatment and further clinical trials.

Korean Traditional Medicine in Treating Patients with Mild Cognitive Impairment: A Multicenter Prospective Observational Case Series

In Korea, patients with mild cognitive impairment can choose to receive treatment of Korean medicine, and Korean medicine hospitals provide specialized medical care for the prevention and management of cognitive disorders. The aim of the study is to explore the role of Korean medicine therapy for patients with mild cognitive impairment in a real clinical setting. Fifteen patients with amnestic mild cognitive impairment were enrolled in this prospective observational study in three Korean medicine hospitals. Korean medicine treatments were delivered by experienced professionals and not restricted to standardized treatment. Outcome measures were prospectively planned to examine the Korean-Montreal Cognitive Assessment (K-MoCA), Korean-Mini Mental State Examination (K-MMSE), and other detailed neuropsychological assessment at the baseline and after 12 and 24 weeks of treatment. Korean medicine treatment for MCI treatment in the real-world clinical setting included herbal medicine and acupuncture. The most frequently used herbs in herbal decoctions were Acori Graminei Rhizoma, Polygalae Radix, and Poria Sclerotium Cum Pini Radix. The herbal medicine formulae used in this study were classified into three categories: tonifying Qi (33.3%), tonifying kidney (46.7%), and calming liver (20%) formulae. In the cognitive ability assessment, the K-MoCA score significantly improved after treatment (mean difference 2.6; 95% CI: 1.3 to 3.9, p=0.001). The K-MMSE score slightly increased after treatment; however, the improvement was not statistically significant (mean difference 0.8; 95% CI: −0.5 to 2.0, p=0.195). In detailed neuropsychological assessment, the cognitive domains of executive functions and memory after the treatment were distinctively improved. In this prospective observational case series, we could see the real clinical environments of treating patients with mild cognitive impairment in Korean medicine hospitals. Patients treated with Korean medicine showed improved results in the neuropsychological assessment after 12 and 24 weeks.

Ginseng berry aqueous extract prevents scopolamine-induced memory impairment in mice

Ginseng berry exhibits a diverse range of pharmacological activities. The present study aimed to examine the neuroprotective effects of ginseng berry aqueous extract (GBE) against oxidative stress and to assess the impact of GBE on memory impairment in mice. In HT-22 cells, GBE pretreatment significantly inhibited glutamate- and hydrogen peroxide-mediated cytotoxicity in a concentration-dependent manner, while treatment with up to 100 µg/ml GBE alone did not change cell viability. In a murine model of scopolamine (SCP)-induced memory impairment, results from the passive avoidance test and the Morris water maze test indicated that GBE administration for 4 weeks prolonged step-through latency time and shortened escape latency time, suggesting that GBE can attenuate deficits in long-term memory induced by SCP. Additionally, GBE prevented SCP-induced reductions in acetylcholine by decreasing acetylcholinesterase activity and upregulating choline acetyltransferase mRNA levels in the hippocampus. GBE mitigated SCP-mediated mRNA decreases in brain-derived neurotrophic factor levels and its associated signaling molecules. Furthermore, GBE administration significantly suppressed malondialdehyde production and increased glutathione levels, catalase activity and superoxide dismutase activity in SCP-induced memory impaired mice. Therefore, the results of the current study indicated that ginseng berry may be a potential candidate for treating or preventing memory deficits that are associated with neurodegenerative disorders.

Novel Multitarget Directed Triazinoindole Derivatives as Anti-Alzheimer Agents

The multifaceted nature of Alzheimer's disease (AD) demands treatment with multitarget-directed ligands (MTDLs) to confront the key pathological aberrations. A novel series of triazinoindole derivatives were designed and synthesized. In vitro studies revealed that all the compounds showed moderate to good anticholinesterase activity; the most active compound 23e showed an IC₅₀ value of 0.56 ± 0.02 μM for AChE and an IC₅₀ value of 1.17 ± 0.09 μM for BuChE. These derivatives are also endowed with potent antioxidant activity. To understand the plausible binding mode of the compound 23e, molecular docking studies and molecular dynamics simulation studies were performed, and the results indicated significant interactions of 23e within the active sites of AChE as well as BuChE. Compound 23e successfully diminished H₂O₂-induced oxidative stress in SH-SY5Y cells and displayed excellent neuroprotective activity against H₂O₂ as well as Aβ-induced toxicity in SH-SY5Y cells in a concentration dependent manner. Furthermore, it did not show any significant toxicity in neuronal SH-SY5Y cells in the cytotoxicity assay. Compound 23e did not show any acute toxicity in rats at doses up to 2000 mg/kg, and it significantly reversed scopolamine-induced memory deficit in mice model. Additionally, compound 23e showed notable in silico ADMET properties. Taken collectively, these findings project compound 23e as a potential balanced MTDL in the evolution process of novel anti-AD drugs.

Design, synthesis, and evaluation of novel N-(4-phenoxybenzyl)aniline derivatives targeting acetylcholinesterase, β-amyloid aggregation and oxidative stress to treat Alzheimer's disease

Novel hybrids N-(4-phenoxybenzyl)aniline were designed, synthesized, and evaluated for their potential AChE inhibitory activity along with antioxidant potential. The inhibitory potential (IC₅₀) of synthesized analogs was evaluated against human cholinesterases (hAChE and hBChE) using Ellman's method. Among all the tested compounds, 42 with trimethoxybenzene substituent showed maximum hAChE inhibition with the competitive type of enzyme inhibition (IC₅₀ = 1.32 µM; Ki = 0.879 µM). Further, parallel artificial membrane permeation assay (PAMPA-BBB) showed favorable BBB permeability by most of the synthesized compounds. Meanwhile, compound 42 also inhibited AChE-induced Aβ aggregation (39.5-66.9%) in thioflavin T assay. The in vivo behavioral studies showed dose-dependent improvement in learning and memory by compound 42. The ex vivo studies also affirmed the significant AChE inhibition and antioxidant potential of compound 42 in brain homogenates.

Chinese Herbal Medicine for Mild Cognitive Impairment Using Montreal Cognitive Assessment: A Systematic Review

Background: Mild cognitive impairment (MCI) prevalence is estimated at 6%-12% of the population. It is possible that early treatment at the MCI stage could reduce progression to more severe cognitive impairment. The Montreal Cognitive Assessment (MoCA) is a sensitive measure used to assess changes in cognitive function. Various Chinese herbal medicines (CHMs) have been tested for effects on MCI using MoCA. Objectives: To evaluate the clinical evidence for CHMs on MoCA scores in MCI. Design: Five biomedical databases in English and Chinese language were searched for randomized controlled trials that compared orally administered CHMs with a control group and assessed changes in cognition using MoCA. Analyses were based on the comparison, control intervention, and study duration. Mean differences and 95% confidence intervals were calculated to evaluate treatment effects. For each study, risk of bias was assessed according to the Cochrane tool. Results: Nineteen studies were included with 16 contributing to the data analyses. Three studies were placebo controlled. Nine compared a CHM with a pharmacotherapy, three combined a CHM with a pharmacotherapy, and one combined CHM with cognitive training. In the two placebo-controlled studies of 24-week duration, results favored the CHMs at end of treatment. Conclusions: The systematic review suggests that the oral application of certain CHMs improved scores on MoCA by 1.76-2.34 points compared with placebo in people with MCI after 24 weeks of treatment. However, these two studies used different CHM formulations. Two studies that tested the same CHM formulation, Bu Yang Huan Wu Tang, in combination with donepezil, reported improvement in the integrative groups, but the studies were not blind and the durations were only 8-12 weeks. Overall, methodological weaknesses limited the strength of the evidence. The herbal formulae included ingredients that have received considerable research attention for their effects on memory and cognition. PROSPERO international prospective register of systematic reviews protocol registration number: CRD42018099650.

Stereoisomers of Schisandrin B Are Potent ATP Competitive GSK-3β Inhibitors with Neuroprotective Effects against Alzheimer's Disease: Stereochemistry and Biological Activity

Glycogen synthase kinase-3β (GSK-3β) is a key enzyme in hyperphosphorylation of tau proteins and is a promising therapeutic target in Alzheimer's disease (AD). Here, we reported, for the first time, that the stereoisomers of Schisandrin B (Sch B), (+)-1, (-)-1, (+)-2, and (-)-2, were potent GSK-3β inhibitors. They were demonstrated to selectively target GSK-3β in an orthosteric binding mode, with IC₅₀ values of 340, 290, 80, and 70 nM, respectively. Further study showed that these stereoisomers can significantly increase the expression of p-GSK-3β (Ser9) and decrease the expressions of p-GSK-3β (Tyr216) and p-GSK-3β (Tyr279). Finally, these compounds can alleviate the cell injury induced by Aβ, and the cognitive disorders in AD mice, especially (+)-2 and (-)-2. Collectively, the stereoisomers of Sch B, especially (+)-2 and (-)-2, were found to be potential selective ATP-competitive GSK-3β inhibitors, which further affected their anti-AD effects. These promising findings explained the biological target of Sch B in AD, and bring a new understanding in the stereochemistry and bioactivities of Sch B.

Antioxidant hydrolyzed peptides from Manchurian walnut (Juglans mandshurica Maxim.) attenuate scopolamine-induced memory impairment in mice

BACKGROUND

Walnut protein, which is obtained as a by-product of oil expression, has not been used efficiently. Although walnuts are beneficial for cognitive functioning, the potential of their protein composition in strengthening learning and memory functions remains unknown. In this study, the inhibition of memory impairment by the Manchurian walnut hydrolyzed peptide (MWHP) was evaluated.

RESULTS

Small-molecular-weight MWHP (<3 kDa) achieved the optimal antioxidative activity. Therefore, MWHP (<3 kDa) was subjected to the following mice trials to evaluate its attenuation effect on memory impairment. In the Morris water maze test, MWHP shortened the total path for searching the platform, reduced the escape latency, and increased the dwelling distance and time in the coverage zone. MWHP also prolonged the latency and diminished errors in the passive avoidance response tests. These behavioral tests demonstrated that MWHP could inhibit scopolamine-induced memory impairment. MWHP improved memory by reducing oxidative stress, inhibiting apoptosis, regulating neurotransmitter functions, maintaining hippocampal CA3 pyramidal neurons, and increasing calmodulin-dependent protein kinase II levels in brain tissues.

CONCLUSION

Experimental results proved that MWHP exhibits potential in improving memory and should be used to develop novel functional food. © 2018 Society of Chemical Industry.

Cognitive-enhancing and antioxidant activities of the aqueous extract from Markhamia tomentosa (Benth.) K. Schum. stem bark in a rat model of scopolamine

BACKGROUND

Plants of the genus Markhamia have been traditionally used by different tribes in various parts of West African countries, including Cameroun. Markhamia tomentosa (Benth.) K. Schum. (Bignoniaceae) is used as an antimalarial, anti-inflammatory, analgesic, antioxidant and anti-Alzheimer agent. The current study was undertaken in order to investigate its anti-amnesic and antioxidant potential on scopolamine-induced cognitive impairment and to determine its possible mechanism of action.

METHODS

Rats were pretreated with the aqueous extract (50 and 200 mg/kg, p.o.), for 10 days, and received a single injection of scopolamine (0.7 mg/kg, i.p.) before training in Y-maze and radial arm-maze tests. The biochemical parameters in the rat hippocampus were also assessed to explore oxidative status. Statistical analyses were performed using two-way ANOVA followed by Tukey's post hoc test. F values for which p < 0.05 were regarded as statistically significant.

RESULTS

In the scopolamine-treated rats, the aqueous extract improved memory in behavioral tests and decreased the oxidative stress in the rat hippocampus. Also, the aqueous extract exhibited anti-acetylcholinesterase activity.

CONCLUSIONS

These results suggest that the aqueous extract ameliorates scopolamine-induced spatial memory impairment by attenuation of the oxidative stress in the rat hippocampus.

Effect of Poria cocos hydroethanolic extract on treating adriamycin-induced rat model of nephrotic syndrome

OBJECTIVE

To evaluate the effect of Poria cocos (Schw.) Wolf hydroethanolic extract (PHE) against nephrotic syndrome (NS) in rats and to identify the potential active components from PHE.

METHODS

The high content compounds were isolated and purified by using column chromatography followed by preparative highperformance liquid chromatography (p-HPLC). Forty male Wistar rats with adriamycin (ADR)-induced NS were randomly divided into 5 groups, 8 in each group: model control group, positive control group (with prednisone treatment), PHE low-dose group, PHE middle-dose group and PHE high-dose group. Another 8 rats were recruited as vehicle control group. All rats received the intragastric administration of corresponding drugs or saline for 30 days. During the experimental period, rats' behavior and appearance were observed and recorded daily, and their body weights were recorded weekly. After treatment, 24-h urine samples were collected to evaluate the urine protein and urine creatinine (Ucr); then the rats were sacrificed to collect carotid blood and to determine the levels of serum total protein (TP), albumin (Alb), globulin (Glo), total cholesterol (TC) and cytokine interlukin-4 (IL-4).

RESULTS

Six acidic components were isolated and identified from the PHE section: pachymic acid, 15α-hydroxydehydrotumulosic acid, trametenolic acid, dehydropachymic acid, 3β-hydroxy-lanosta-7,9(11), 24-trien-21-oic-acid and dehydroeburicoic acid. Compared with the model control group, the urine protein content were significantly decreased in the PHE treatment groups and positive control group (P<0.05), especially PHE middle-dose group (P<0.01). The Ucr values and serum levels of TP, Glo, TC and IL-4 in PHE low- and middle-dose groups were also presented obvious recover tendency as compared with the model control group (P<0.05 or P<0.01). However, positive control group and all PHE groups indicated no significant therapeutic effect on raising Alb value, although PHE low- and middle-dose treatment groups showed better outcomes than positive control group (P>0.05).

CONCLUSIONS

PHE showed an encouraging therapeutic effect against ADR-induced NS in a rat model. PHE might be a group of effective substances for the treatment of NS.

β-Asarone Rescues Pb-Induced Impairments of Spatial Memory and Synaptogenesis in Rats

Chronic lead (Pb) exposure causes cognitive deficits. This study aimed to explore the neuroprotective effect and mechanism of β-asarone, an active component from Chinese Herbs Acorus tatarinowii Schott, to alleviate impairments of spatial memory and synaptogenesis in Pb-exposed rats. Both Sprague-Dawley developmental rat pups and adult rats were used in the study. Developmental rat pups were exposed to Pb throughout the lactation period and β-asarone (10, 40mg kg^-1, respectively) was given intraperitoneally from postnatal day 14 to 21. Also, the adult rats were exposed to Pb from embryo stage to 11 weeks old and β-asarone (2.5, 10, 40mg kg^-1, respectively) was given from 9 to 11 weeks old. The level of β-asarone in brain tissue was measured by High Performance Liquid Chromatography. The Morris water maze test and Golgi-Cox staining method were used to assess spatial memory ability and synaptogenesis. The protein expression of NR2B subunit of NMDA receptor, Activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) and Wnt family member 7A (Wnt7a) in hippocampus, as well as mRNA expression of Arc/Arg3.1 and Wnt7a, was also explored. We found that β-asarone could pass through the blood brain barrier quickly. And β-asarone effectively attenuated Pb-induced reduction of spine density in hippocampal CA1 and dentate gyrus areas in a dose-dependent manner both in developmental and adult rats, meanwhile the Pb-induced impairments of learning and memory were partially rescued. In addition, β-asarone effectively up-regulated the protein expression of NR2B, Arc and Wnt7a, as well as the mRNA levels of Arc/Arg3.1 and Wnt7a, which had been suppressed by Pb exposure. The results suggest the neuroprotective properties of β-asarone against Pb-induced memory impairments, and the effect is possibly through the regulation of synaptogenesis, which is mediated via Arc/Arg3.1 and Wnt pathway.

Effects of grape seed proanthocyanidin on Alzheimer's disease in vitro and in vivo

Grape seed proanthocyanidin (GSPA) consists of catechin, epicatechin and epicatechin gallate, which are strong antioxidants that are beneficial to health and may attenuate or prevent Alzheimer's disease (AD). In the present study, the effects of GSPA on pheochromocytoma (PC12) cell viability were determined using cell counting kit-8 and lactate dehydrogenase (LDH) assays, whereas apoptosis and mitochondrial membrane potential (Ψm) were measured via flow cytometry analysis. The effect of GSPA administration on the behavior and memory of amyloid precursor protein (APP)/presenilin-1 (PS-1) double transgenic mice was assessed using a Morris water maze. APP Aβ peptides and tau hyperphosphorylation were examined by western blotting; whereas the expression levels of PS-1 were evaluated by reverse transcription-quantitative polymerase chain reaction and compared with pathological sections stained with hematoxylin-eosin and Congo red. Data from the in vitro experiments demonstrated that GSPA significantly alleviated Aβ25–35 cytotoxicity and LDH leakage ratio, inhibited apoptosis and increased Ψm. The findings from the in vivo experiments showed a significant enhancement in cognition and spatial memory ability, an improvement in the pathology of APP and tau protein and a decrease in PS-1 mRNA expression levels. Therefore, the results of the present study indicated that GSPA may be a novel therapeutic strategy for the treatment of AD or may, at the very least, improve the quality of life of patients with AD.

Chinese Herbal Medicine for Mild Cognitive Impairment: A Systematic Review and Meta-Analysis of Cognitive Outcomes

Mild cognitive impairment (MCI) is a condition that may be prodromal to the development of dementia. There remain, as yet, no approved pharmaceutical interventions for MCI. Chinese herbal medicines (CHMs) have a long history of use for cognitive impairments and some plant ingredients have shown neuroprotective actions in experimental studies. This review assesses the current clinical evidence from controlled clinical trials for the effects of CHMs on cognitive outcomes as measured by Mini-mental state examination (MMSE) or Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog). Fifty one studies (4026 participants) were included. These compared CHM with placebo, supportive care, pharmaceutical treatment or combined CHM with a pharmaceutical in an integrative setting. For the eight randomised controlled trials (RCTs) of comparisons with placebo, MMSE was significantly higher in the CHM groups (MD 1.56 [0.78, 2.34] I²  = 85%, n = 503), similarly for eight RCTs of comparisons with supportive care (MD 1.77 [1.33, 2.21] I²  = 0%, n = 555). Benefits were also evident in comparisons with some pharmaceuticals and with integrative treatment. The small size of most studies and methodological weaknesses mean that these results should be interpreted with caution. Further studies employing rigorous methods are required to investigate the potential benefits of these CHMs for MCI. Copyright © 2016 John Wiley & Sons, Ltd.

Black ginseng-enriched Chong-Myung-Tang extracts improve spatial learning behavior in rats and elicit anti-inflammatory effects in vitro

Background

Chong-Myung-Tang (CMT) extract is widely used in Korea as a traditional herbal tonic for increasing memory capacity in high-school students and also for numerous body ailments since centuries. The use of CMT to improve the learning capacity has been attributed to various plant constituents, especially black ginseng, in it. Therefore, in this study, we have first investigated whether black ginseng-enriched CMT extracts affected spatial learning using the Morris water maze (MWM) test. Their molecular mechanism of action underlying improvement of learning and memory was examined in vitro.

Methods

We used two types of black ginseng-enriched CMT extracts, designated as CM-1 and CM-2, and evaluated their efficacy in the MWM test for spatial learning behavior and their anti-inflammatory effects in BV2 microglial cells.

Results

Our results show that both black ginseng-enriched CMT extracts improved the learning behavior in scopolamine-induced impairment in the water maze test. Moreover, these extracts also inhibited nitric oxide production in BV2 cells, with significant suppression of expression of proinflammatory cytokines, especially inducible nitric oxide synthase, cyclooxygenase-2, and interleukin-1β. The protein expression of mitogen-activated protein kinase and nuclear factor-κB pathway factors was also diminished by black ginseng-enriched CMT extracts, indicating that it not only improves the memory impairment, but also acts a potent anti-inflammatory agent for neuroinflammatory diseases.

Conclusion

Our research for the first time provides the scientific evidence that consumption of black ginseng-enriched CMT extract as a brain tonic improves memory impairment. Thus, our study results can be taken as a reference for future neurobehavioral studies.

Effects of the Methanolic Extract of Vitellaria paradoxa Stem Bark Against Scopolamine-Induced Cognitive Dysfunction and Oxidative Stress in the Rat Hippocampus

Vitellaria paradoxa C.F. Gaertn (Sapotaceae) is a perennial three which naturally grows in the northern part of Cameroon. It has been traditionally used in the Cameroonian folk medicine for treating inflammation and pain. In the present study, we evaluate the possible anti-amnesic and antioxidative effects of the methanolic extract of V. paradoxa stem bark in an Alzheimer's disease (AD) rat model of scopolamine. Rats received a single injection of scopolamine (1.5 mg/kg) before behavioral testing and were treated with the methanolic extract (25 and 50 mg/kg), daily, for eight continuous days. Also, the antioxidant activity in the hippocampus was assessed using the total content of reduced glutathione and malondialdehyde levels. The scopolamine-treated rats exhibited the following: decrease of exploratory time and discrimination index within the novel object recognition test, decrease of spontaneous alternations percentage within Y-maze task, and increase of working memory errors, reference memory errors, and time taken to consume all five baits within radial arm-maze task. Administration of the methanolic extract significantly improved these parameters, suggesting positive effects on memory formation processes and antioxidant potential. Our results suggest that the methanolic extract ameliorates scopolamine-induced memory impairment by attenuation of the oxidative stress in the rat hippocampus.

Effect of Beta-Asarone on Impairment of Spatial Working Memory and Apoptosis in the Hippocampus of Rats Exposed to Chronic Corticosterone Administration

β-asarone (BAS) is an active component of Acori graminei rhizoma, a traditional medicine used clinically in treating dementia and chronic stress in Korea. However, the cognitive effects of BAS and its mechanism of action have remained elusive. The purpose of this study was to examine whether BAS improved spatial cognitive impairment induced in rats following chronic corticosterone (CORT) administration. CORT administration (40 mg/kg, i.p., 21 days) resulted in cognitive impairment in the avoidance conditioning test (AAT) and the Morris water maze (MWM) test that was reversed by BAS (200 mg/kg, i.p). Additionally, as assessed by immunohistochemistry and RT-PCR analysis, the administration of BAS significantly alleviated memory-associated decreases in the expression levels of brain-derived neurotrophic factor (BDNF) and cAMP-response element-binding protein (CREB) proteins and mRNAs in the hippocampus. Also, BAS administration significantly restored the expression of Bax and Bcl-2 mRNAs in the hippocampus. Thus, BAS may be an effective therapeutic for learning and memory disturbances, and its neuroprotective effect was mediated, in part, by normalizing the CORT response, resulting in regulation of BDNF and CREB functions and anti-apoptosis in rats.

Antiamnesic and Antioxidants Effects of Ferulago angulata Essential Oil Against Scopolamine-Induced Memory Impairment in Laboratory Rats

Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains, hemorrhoids, snake bite, ulcers and as sedative. In the present study, the effects of inhaled F. angulata essential oil (1 and 3%, daily, for 21 days) on spatial memory performance were assessed in scopolamine-treated rats. Scopolamine-induced memory impairments were observed, as measured by the Y-maze and radial arm-maze tasks. Decreased activities of superoxide dismutase, glutathione peroxidase and catalase along with increase of acetylcholinesterase activity and decrease of total content of reduced glutathione were observed in the rat hippocampal homogenates of scopolamine-treated animals as compared with control. Production of protein carbonyl and malondialdehyde significantly increased in the rat hippocampal homogenates of scopolamine-treated animals as compared with control, as a consequence of impaired antioxidant enzymes activities. Additionally, in scopolamine-treated rats exposure to F. angulata essential oil significantly improved memory formation and decreased oxidative stress, suggesting memory-enhancing and antioxidant effects. Therefore, our results suggest that multiple exposures to F. angulata essential oil ameliorate scopolamine-induced spatial memory impairment by attenuation of the oxidative stress in the rat hippocampus.

Deer bone extract prevents against scopolamine-induced memory impairment in mice

Deer bone has been used as a health-enhancing food as well as an antiaging agent in traditional Oriental medicine. Recently, the water extract of deer bone (DBE) showed a neuroprotective action against glutamate or Aβ1-42-induced cell death of mouse hippocampal cells by exerting antioxidant activity through the suppression of MAP kinases. The present study is to examine whether DBE improves memory impairment induced by scopolamine. DBE (50, 100 or 200 mg/kg) was administered orally to mice for 14 days, and then scopolamine (2 mg/kg, i.p.) was administered together with DBE for another 7 days. Memory performance was evaluated in the Morris water maze (MWM) test and passive avoidance test. Also, brain acetylcholinesterase (AChE) and choline acetyltransferase (ChAT) activity, biomarkers of oxidative stress and the loss of neuronal cells in the hippocampus, was evaluated by histological examinations. Administration of DBE significantly restored memory impairments induced by scopolamine in the MWM test (escape latency and number of crossing platform area), and in the passive avoidance test. Treatment with DBE inhibited the AChE activity and increased the ChAT activity in the brain of memory-impaired mice induced by scopolamine. Additionally, the administration of DBE significantly prevented the increase of lipid peroxidation and the decrease of glutathione level in the brain of mice treated with scopolamine. Also, the DBE treatment restored the activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and glutathione reductase to control the level. Furthermore, scopolamine-induced oxidative damage of neurons in hippocampal CA1 and CA3 regions were prevented by DBE treatment. It is suggested that DBE may be useful for memory improvement through the regulation of cholinergic marker enzyme activities and the suppression of oxidative damage of neurons in the brain of mice treated with scopolamine.

The multi-herbal formula Chong-Myung-Tang improves spatial memory and increases cell genesis in the dentate gyrus of aged mice

Chong-Myung-Tang (CMT) is a multi-herbal formula that has been used to improve memory. However, the potential mechanism remains unknown. The present study investigated the effects of CMT (50, 100, and 200 mg/kg) on spatial memory of aged mice. The behavioral training tests indicated that 200 mg/kg CMT treatment can significantly improve spatial memory of aged mice in the Morris water maze. Moreover, cell survival was examined by injecting bromodeoxyuridine (BrdU) on the first three days. The result showed that 200 mg/kg CMT treatment significantly increased cell survival in the dentate gyrus. Cell proliferation was determined by injecting BrdU 2 h before the mice were killed. The result suggested that CMT treatments had no influence on cell proliferation in the dentate gyrus. Thus, an increase in cell survival in the dentate gyrus stimulated by CMT may be involved in the effect of CMT on spatial memory improvement.

Efficacy of Acorus calamus on collagen maturation on full thickness cutaneous wounds in rats

Background:

The rhizomes of Acorus calamus and their essential oil are widely used in the flavoring industry and production of alcoholic beverages in Europe. Recent reports have confirmed the presence of several pharmacological components in the rhizomes of A. calamus.

Objective:

The objective of this study was to find out the efficacy of topical administration of ethanolic extract of A. calamus on dermal wound healing in rats. Wound healing is a natural process occurring in living organisms, which results in a complete or partial remodeling of injured tissue and ultimately progresses to the formation of a fibrous scar. Several natural products have been reported to augment the wound healing process.

Materials and Methods:

An ethanolic extract of A. calamus was prepared and its wound-healing efficacy was studied. An excision wound was made on the back of the rat and 200 μL (40 mg/kg body weight) of the A. calamus extract was applied topically once daily for the treated wounds. The control wounds were treated with 200 μL of phosphate buffered saline.

Results:

The granulation tissues formed were removed at 4, 8 and 12 days and biochemical parameters such as deoxyribonucleic acid, total protein, total collagen, hexosamine and uronic acids were measured. The amount of type I/III collagen formed in control and treated wound tissues was evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The epithelialization time, tensile strength and histological examination of the wounds were also studied. Biochemical analyses of the granulation tissues revealed a significant increase in collagen, hexosamine and uronic acid when compared with the control. The tensile strength of extract treated wounds was found to increase by 112%. A significant reduction in lipid peroxide levels suggested that A. calamus possesses antioxidant components.

Conclusions:

The results strongly confirm the beneficial effects of A. calamus in augmenting the wound healing process.

Traditional Korean East Asian medicines and herbal formulations for cognitive impairment

Hanbang, the Traditional Korean Medicine (TKM), is an inseparable component of Korean culture both within the country, and further afield. Korean traditional herbs have been used medicinally to treat sickness and injury for thousands of years. Oriental medicine reflects our ancestor’s wisdom and experience, and as the elderly population in Korea is rapidly increasing, so is the importance of their health problems. The proportion of the population who are over 65 years of age is expected to increase to 24.3% by 2031. Cognitive impairment is common with increasing age, and efforts are made to retain and restore the cognition ability of the elderly. Herbal materials have been considered for this purpose because of their low adverse effects and their cognitive-enhancing or anti-dementia activities. Herbal materials are reported to contain several active compounds that have effects on cognitive function. Here, we enumerate evidence linking TKMs which have shown benefits in memory improvements. Moreover, we have also listed Korean herbal formulations which have been the subject of scientific reports relating to memory improvement.

Neuroprotective effect of Liuwei Dihuang decoction on cognition deficits of diabetic encephalopathy in streptozotocin-induced diabetic rat

ETHNOPHARMACOLOGICAL RELEVANCE

Liuwei Dihuang decoction (LWDHD) is a well-known prescription of traditional Chinese medicine (TCM) and consists of six crude drugs including Rehmannia glutinosa Libosch. (family: Scrophulariaceae), Cornus officinalis Sieb. (family: Cornaceae), Dioscorea oppositifolia L. (family: Dioscoreaceae), Paoenia ostii (family: Paeoniaceae), Alisma orientale (G. Samuelsson) Juz (family: Alismataceae) and Poria cocos (Schw.) Wolf (family: Polyporaceae). It has been used for the treatment of "Kidney-Yin" deficiency syndrome in clinic in China for a long time. Recent studies found that LWDHD had a potential benefit for the treatment of diabetic complications. The aim of the present study is to investigate the neuroprotective effect of LWDHD on memory and cognition deficits in streptozotocin (STZ)-induced diabetic encephalopathy (DE) rats.

MATERIALS AND METHODS

Adult male Sprague Dawley (SD) rats were fed with high-glucose-fat diet for 50 days and then received an intraperitoneal injection of STZ (40 mg/kg) to induce DE model. Morris water maze test was used to evaluate the memory and cognition capability of DE rats. Choline acetyltransferase (ChAT), acetylcholinesterase (AChE), Na(+)-K(+)-ATP enzyme, iNOS and GSH kits were used to determine their activities or content in hippocampus. TUNEL staining, immunohistochemistry and Congo red staining were conducted to evaluate the apoptosis, caspase-3 protein expression, insulin-like growth factors 1 (IGF-1) and brain derived neurophic factor (BDNF) expressions, as well as Aβ deposition.

RESULTS

The treatment with LWDHD (1 and 2g/kg, p.o., once daily, 30 days) could significantly reduce the escape latency time and path length, and obviously enhance the spent time in the target quadrant and platform crossings in Morris water maze test compared with model group (P<0.05, P<0.01). LWDHD could also significantly decrease the level of fasting blood glucose, increase Na(+)-K(+)-ATP enzyme and ChAT activities, enhance remarkedly GSH level while decrease significantly AChE and iNOS activities in hippocampus (P<0.05, P<0.01). Furthermore, TUNEL staining, Congo red staining and immunohistochemistry showed that LWDHD significantly improved the expressions of IGF-1 and BDNF, attenuated the neural apoptosis, overexpression of caspase-3 and Aβ deposition in the hippocampus and cerebral cortex of STZ-induced DE rats (P<0.01).

CONCLUSION

Our findings suggested that LWDHD had a neuroprotective effect on DE rats. LWDHD may be of benefit in the treatment of DE.

Catalpol Induces Neuroprotection and Prevents Memory Dysfunction through the Cholinergic System and BDNF

To investigate the role and mechanism of catalpol on neuroprotective effects and memory enhancing effects simultaneously, neuroprotective effects of catalpol were assessed by neurological deficits score, TTC staining, and cerebral blood flow detecting. Morris water maze was employed to investigate its effects on learning and memory and then clarify its possible mechanisms relating the central cholinergic system and BDNF. Edaravone and oxiracetam were used for positive control drugs based on its different action. Results showed that catalpol and edaravone significantly facilitated neurological function recovery, reduced infarction volume, and increased cerebral blood flow in stroke mice. Catalpol and oxiracetam decreased the escape latency significantly and increased the numbers of crossing platform obviously. The levels of ACh, ChAT, and BDNF in catalpol group were increased in a dose-dependent manner, and AChE declined with a U-shaped dose-response curve. Moreover, the levels of muscarinic AChR subtypes M₁ and M₂ in hippocampus were considerably raised by catalpol. These results demonstrated that catalpol may be useful for neuroprotection and memory enhancement, and the mechanism may be related to the central cholinergic system.

The effects of Gouqi extracts on Morris maze learning in the APP/PS1 double transgenic mouse model of Alzheimer's disease

The present study examined the effects of Gouqi (Lycium barbarum) on the learning and memory abilities of an APP/PS1 double transgenic mouse model of Alzheimer’s disease. We employed a Morris water maze to examine the spatial memory in this mice line with or without Gouqi extracts treatment. We identified that 2 weeks of oral administration of Gouqi extracts at 10 mg/kg improved the performance of the APP/PS1 mice in the learning and the memory retrieval phases of the Morris maze. In correlation with this, the levels of Aβ(1–42) in hippocampal tissue were reduced by the Gouqi treatment. We conclude that pharmacological treatment with Gouqi extracts is beneficial at the later stages of Alzheimer’s disease.

Cerebrovascular protection of β-asarone in Alzheimer's disease rats: a behavioral, cerebral blood flow, biochemical and genic study

AIM OF THE STUDY

Recent studies have suggested that β-asarone have neuroprotective and cardiovascular protective effects in animal model. However, the influence of β-asarone on cerebrovascular system has not been explored so far. Therefore, present study was designed to determine whether repeated exposures to β-asarone resulted in positive effects on cerebrovascular function in AD rats.

MATERIALS AND METHODS

Alzheimer's disease induced rats was established by injecting both D-galactose (D-gal) and aluminum chloride (AlCl(3)) into abdominal cavity for 42 days. After injection of AlCl(3) and D-gal or saline for 28 days, the rats were treated with volume-matched vehicle or β-asarone (25mg/kg, 50mg/kg or 100mg/kg, i.h.) or Nimodipine (40mg/kg, i.g) once daily for consecutive 14 days, respectively. Behavioral responses of animals were assessed in a Morris water maze. CBF was measured by laser Doppler flowmetry. At the end of this period all rats were sacrificed, lactic acid, pyruvic acid content, Na+K+ATPase activity were determined in brain tissue homogenate to estimate the brain biochemical changes and mRNA expression of ET-1, eNOS and APP was measured with real-time RT-PCR method.

RESULTS

The spatial navigation task latencies, the times through platform zone and the time for the first through platform zone in the target quadrant in probe task, rCBF of right parietal lobe, the contents of lactic acid, pyruvic acid, and the activity of Na-K-ATP of cortex, and ET-1 and eNOS mRNA expression in hippocampus of AG rats were different from those of BG, P<0.05; The level of APP mRNA expression in model control group rats was higher than that in BG, though there was not a statistically significant difference, P>0.05; Compared with AG, HG rats spatial navigation task latencies were shorter, in probe task the times through platform zone in the target quadrant were bigger, rCBF and blood cell concentration of right parietal lobe were higher, the contents of pyruvic acid was lower, the activity of Na-K-ATP was higher, and ET-1 mRNA expression in hippocampus was lower, P<0.05; The level of eNOS and APP mRNA expression in HG rats was lower than that in AG, though there was not a statistically significant difference, P>0.05;

CONCLUSION

The present results suggested that β-asarone may be useful in memory impairment due to its cerebrovascular protection in AD rats and may develop as a therapeutic drug for treatment of AD patients.

Danggui-Shaoyao-San ameliorates cognition deficits and attenuates oxidative stress-related neuronal apoptosis in d-galactose-induced senescent mice

ETHNOPHARMACOLOGICAL RELEVANCE

Danggui-Shaoyao-San (DSS), a famous traditional Chinese medicine formula consisting of six herbal medicines, has been used to treat gynecological disorders and neural dysfunctions.

AIM OF THE STUDY

The present study was carried out to investigate the effects of DSS on cognitive ability and oxidative stress-related neuronal apoptosis in the hippocampus of aging mice induced by d-galactose (d-gal) to elucidate the underlying molecular mechanisms.

MATERIALS AND METHODS

Ethanol extract of DSS (DE) were orally administered to d-gal-induced senescent mice for six weeks. The cognitive ability was determined by the methods of step-down type passive avoidance test and Morris water maze test. The activities of superoxide dismutase (SOD) and nitric oxide synthase (NOS), and levels of carbonyl protein (CP), glutathione (GSH), malondialdehyde (MDA) and nitric oxide (NO) were also examined. Furthermore, the expression of apoptotic related proteins in hippocampus of d-gal-treated mice, such as Bcl-2, Bax and caspase-3 proteins, were determined by immunohistochemistry.

RESULTS

DE at the doses of 1.8, 3.6 and 7.2g/kg significantly enhanced the cognitive performances and restored the abnormal activities of SOD and NOS and levels of CP, MDA, GSH and NO induced by d-gal. Moreover, the neural apoptosis in the hippocampus of d-gal-treated mice was improved by DE through regulating the expression of Bcl-2, Bax and caspase-3.

CONCLUSION

These results demonstrate that DE has neuroprotective effects in d-gal-induced senescent mice by ameliorating oxidative stress induced neuronal apoptosis in the brain.