Effect of Polygala tenuifolia root extract on scopolamine-induced impairment of rat spatial cognition in an eight-arm radial maze task

Composition of Whole Grain Dietary Fiber and Phenolics and Their Impact on Markers of Inflammation

Inflammation is an important biological response to any tissue injury. The immune system responds to any stimulus, such as irritation, damage, or infection, by releasing pro-inflammatory cytokines. The overproduction of pro-inflammatory cytokines can lead to several diseases, e.g., cardiovascular diseases, joint disorders, cancer, and allergies. Emerging science suggests that whole grains may lower the markers of inflammation. Whole grains are a significant source of dietary fiber and phenolic acids, which have an inverse association with the risk of inflammation. Both cereals and pseudo-cereals are rich in dietary fiber, e.g., arabinoxylan and β-glucan, and phenolic acids, e.g., hydroxycinnamic acids and hydroxybenzoic acids, which are predominantly present in the bran layer. However, the biological mechanisms underlying the widely reported association between whole grain consumption and a lower risk of disease are not fully understood. The modulatory effects of whole grains on inflammation are likely to be influenced by several mechanisms including the effect of dietary fiber and phenolic acids. While some of these effects are direct, others involve the gut microbiota, which transforms important bioactive substances into more beneficial metabolites that modulate the inflammatory signaling pathways. Therefore, the purpose of this review is twofold: first, it discusses whole grain dietary fiber and phenolic acids and highlights their potential; second, it examines the health benefits of these components and their impacts on subclinical inflammation markers, including the role of the gut microbiota. Overall, while there is promising evidence for the anti-inflammatory properties of whole grains, further research is needed to understand their effects fully.

Impact of Sinapic Acid on Bovine Serum Albumin Thermal Stability

The thermal stability of bovine serum albumin (BSA) in Tris buffer, as well as the effect of sinapic acid (SA) on protein conformation were investigated via calorimetric (differential scanning microcalorimetry-μDSC), spectroscopic (dynamic light scattering-DLS; circular dichroism-CD), and molecular docking approaches. μDSC data revealed both the denaturation (endotherm) and aggregation (exotherm) of the protein, demonstrating the dual effect of SA on protein thermal stability. With an increase in ligand concentration, (i) protein denaturation shifts to a higher temperature (indicating native form stabilization), while (ii) the aggregation process shifts to a lower temperature (indicating enhanced reactivity of the denatured form). The stabilization effect of SA on the native structure of the protein was supported by CD results. High temperature (338 K) incubation induced protein unfolding and aggregation, and increasing the concentration of SA altered the size distribution of the protein population, as DLS measurements demonstrated. Complementary information offered by molecular docking allowed for the assessment of the ligand binding within the Sudlow's site I of the protein. The deeper insight into the SA-BSA interaction offered by the present study may serve in the clarification of ligand pharmacokinetics and pharmacodynamics, thus opening paths for future research and therapeutic applications.

Sword Bean (Canavalia gladiata) Pods Induce Differentiation in MC3T3-E1 Osteoblast Cells by Activating the BMP2/SMAD/RUNX2 Pathway

Sword bean (SB) contains various phytochemicals, such as flavonoids, tannins, saponins, and terpenoids. Although the evaluation of its potential functions, including antioxidant, anti-obesity, anti-inflammatory, liver protection, and antiangiogenic activities, has been widely reported, research on their use in osteoporosis prevention is insufficient. Furthermore, while various studies are conducted on SB, research on sword bean pods (SBP) is not yet active, and little is known about it. Therefore, this study investigated the effects of promoting osteoblast differentiation of MC3T3-E1 cells using SB and SBP extracts and their mechanisms. We show that SBP extracts increase osteoblast proliferation, mineralization-activated alkaline phosphatase (ALP), and collagen synthesis activities. Additionally, treatment with SBP extract increased the expression of markers related to osteoblast differentiation, such as ALP, SPARC, RUNX2, COL-I, BMP2, OCN, and OPN. It was confirmed that SBP induces differentiation by activating the BMP2/SMAD/RUNX2 pathway. We also show that SBP is more effective than SB, and SBP may be useful in assimilating bone minerals and preventing osteoporosis.

Preparation and Characterization of Transethosome Formulation for the Enhanced Delivery of Sinapic Acid

Sinapic acid (SA) is a bioactive phenolic acid; its diverse properties are its anti-inflammatory, antioxidant, anticancer, and antibacterial activities. The bioactive compound SA is poorly soluble in water. Our goal was to formulate SA-transethosomes using thin-film hydration. The prepared formulations were examined for various parameters. In addition, the optimized formulation was evaluated for surface morphology, in-vitro penetration studies across the Strat M®, and its antioxidant activity. The optimized formulation (F5) exhibited 74.36% entrapment efficacy. The vesicle size, zeta potential, and polydispersity index were found to be 111.67 nm, -7.253 mV, and 0.240, respectively. The surface morphology showed smooth and spherical vesicles of SA-transethosomes. In addition, the prepared SA-transethosomes exhibited enhanced antioxidant activity. The SA-transethosomes demonstrated considerably greater penetration across the Strat M® membrane during the study. The flux of SA and SA-transethosomes through the Strat M® membrane was 1.03 ± 0.07 µg/cm2/h and 2.93 ± 0.16 µg/cm2/h. The enhancement ratio of SA-transethosomes was 2.86 ± 0.35 compared to the control. The SA-transethosomes are flexible nano-sized vesicles and are able to penetrate the entrapped drug in a higher concentration. Hence, it was concluded that SA-transethosome-based approaches have the potential to be useful for accentuating the penetrability of SA across the skin.

Antibacterial and Antiproliferative Activities of Azadirachta indica Leaf Extract and Its Effect on Oil-in-Water Food Emulsion Stability

The present study aims to identify and quantify the phenolic compounds of Azadirachta indica leaf extract using HPLC-MS and to evaluate the antioxidant, antibacterial (against different Gram-positive and negative bacteria) and in vitro anti-proliferative activities of this extract (against breast, human liver and cervix adenocarcinoma-derived cells). The application of this extract as a natural antioxidant for food preservation was also tested on oil-in-water food emulsions for the first time in the present work in order to determine the use of Azadirachta indica leaves as a natural additive to preserve the food against lipid oxidation and rancidity. The results obtained revealed that 50%-aqueous ethanol leaf extract showed the best extraction yield (25.14%), which was characterized by a high content in phenolic compounds and strong antioxidant activity. Moreover, this leaf extract inhibited the growth of the bacterial strains tested (Staphylococcus aureus, Escherichia coli, Salmonella paratyphi and Micrococcus luteus) and showed better anti-proliferative activity against breast and cervix adenocarcinoma-derived cells than human liver cancer cells after 48 h of treatment. Additionally, Azadirachta indica leaf extract showed almost similar effects as gallic acid solutions (0.25% and 0.5%) in preserving the oxidation of oil-in-water food emulsions and prevented the formation of secondary oxidation products (malondialdehyde) as well. The results obtained suggested that extracts of Azadirachta indica leaves are a potential source of antioxidant and antibacterial compounds and pointed to the potential of these natural extracts as therapeutic agents.

Hydroxypropyl-β-Cyclodextrin for Delivery of Sinapic Acid via Inclusion Complex Prepared by Solvent Evaporation Method

The goal of this study was to increase the aqueous solubility and dissolution rate of sinapic acid (SA) by formulating binary inclusion complex (BIC) of SA with hydroxypropyl-β-cyclodextrin (HPβCD) using solvent evaporation (SE) technology. The phase solubility and dissolution studies were conducted to determine the solubility and in vitro release rate of SA. In addition, the prepared inclusion complex was characterized for solid state characterization using techniques such as DSC, PXRD, SEM, and FTIR. Moreover, the prepared SA-BIC was evaluated for its antioxidant activity. Results revealed that the SA solubility can be shown to improve with a change in HPβCD concentration. About 2.59 times higher solubility of SA in water was noticed in the presence of HPβCD (10 mM). Dissolution study demonstrated that the 34.11 ± 4.51% of SA was released from binary physical mixture (BPM), while the maximum release of 46.27 ± 2.79% of SA was observed for SA-BIC prepared by SE method. The prepared SA-BIC demonstrated distinctive properties when compared to pure SA, which was demonstrated by different analytical methods, such as DSC, PXRD, SEM, and FTIR, as evidence of SA inclusion into HPβCD cavity. Further, it was observed that SA-BIC displayed stronger DPPH radical scavenging activity than SA. In conclusion, SE technology considerably enhanced the complexity of SA with HPβCD, and these observations could help to heighten the SA solubility, which may lead to a better bioavailability.

Effect of Radix Polygalae extract on the colonic dysfunction in rats induced by chronic restraint stress

ETHNOPHARMACOLOGICAL RELEVANCE

Radix Polygalae, a commonly used traditional Chinese herb, has conventionally functioned in tranquilization and sedation, where anti-inflammation may be the underlying mechanism.

AIM OF THE STUDY

Chronic restraint stress (CRS), a risk factor for the etiology of intestinal disorders, was used in the present study to examine whether Radix Polygalae extract (RPE) could modulate colonic dysfunction in CRS rats.

MATERIALS AND METHODS

Wistar rats were exposed to 28-day CRS (6 h daily), and RPE (135 mg/kg and 270 mg/kg) was intragastrically administered 1 h before CRS. Subsequently, the gut microbiota was determined using metagenomic sequencing. Colonic proinflammatory interleukin-1β, -6, and -18 were assayed using qRT-PCR and ELISA. Tight junction proteins were quantified by qRT-PCR and western blotting (WB), and tryptophan metabolic enzymes and metabolites were determined using qRT-PCR and UFLC-QTRAP-5500/MS. Moreover, protein expression of colonic tight junction proteins, NF-κB-NLRP3 signaling involved in the underlying mechanism of RPE were detected by WB.

RESULTS

RPE significantly decreased proinflammatory cytokines and reshaped the gut microbiota, especially the probiotics, including Lactobacillus and Bacteroides. Moreover, RPE could modulate the metabolite contents and enzyme expression associated with colonic tryptophan-kynurenine (TRP-KYN) metabolism and could increase tight junction protein expression in CRS rats. Furthermore, RPE inhibited the activation of NF-κB-NLRP3 signaling in the colon of CRS rats.

CONCLUSION

RPE could modulate colonic inflammation, colonic microbiota, tight junction, TRP-KYN metabolism and NF-κB-NLRP3 signaling to reach a colonic balance of CRS rats. The present study helped us to better understand and appreciate the various beneficial effects of RPE.

Nutraceutical Interventions for Post-Traumatic Stress Disorder in Animal Models: A Focus on the Hypothalamic–Pituitary–Adrenal Axis

Post-traumatic stress disorder (PTSD) occurs after exposure to traumatic events and is characterized by overwhelming fear and anxiety. Disturbances in the hypothalamic–pituitary–adrenal (HPA) axis are involved in the pathogenesis of mood disorders, including anxiety, PTSD, and major depressive disorders. Studies have demonstrated the relationship between the HPA axis response and stress vulnerability, indicating that the HPA axis regulates the immune system, fear memory, and neurotransmission. The selective serotonin reuptake inhibitors (SSRIs), sertraline and paroxetine, are the only drugs that have been approved by the United States Food and Drug Administration for the treatment of PTSD. However, SSRIs require long treatment times and are associated with lower response and remission rates; therefore, additional pharmacological interventions are required. Complementary and alternative medicine therapies ameliorate HPA axis disturbances through regulation of gut dysbiosis, insomnia, chronic stress, and depression. We have described the cellular and molecular mechanisms through which the HPA axis is involved in PTSD pathogenesis and have evaluated the potential of herbal medicines for PTSD treatment. Herbal medicines could comprise a good therapeutic strategy for HPA axis regulation and can simultaneously improve PTSD-related symptoms. Finally, herbal medicines may lead to novel biologically driven approaches for the treatment and prevention of PTSD.

A review of behavioral methods for the evaluation of cognitive performance in animal models: Current techniques and links to human cognition

INTRODUCTION

Memory is defined as the ability to store, maintain and retrieve information. Learning is the acquisition of information that changes behavior and memory. Stress, dementia, head trauma, amnesia, Alzheimer's, Huntington, Parkinson's, Wernicke-Korsakoff syndrome (WKS) may be mentioned among the diseases in which memory and learning are affected. The task of understanding deficits in memory and learning in humans is daunting due to the complexity of neural and cognitive mechanisms in the nervous system. This job is made more difficult for clinicians and researchers by the fact that many techniques used to research memory are not ethically acceptable or technically feasible for use in humans. Thus, animal models have been necessary alternative for studying normal and disordered learning and memory. This review attempts to bridge these domains to allow biomedical researchers to have a firm grasp of "memory" and "learning" as constructs in humans whereby they may then select the proper animal cognitive test.

RESULTS AND CONCLUSION

Various tests (open field habituation test, Y-maze test, passive avoidance test, step-down inhibitory avoidance test, active avoidance test, 8-arms radial maze test, Morris water maze test, radial arm water maze, novel object recognition test and gait function test) have been designed to evaluate different kinds of memory. Each of these tests has their strengths and limits. Abnormal results obtained using these tasks in non-human animals indicate malfunctions in memory which may be due to several physiological and psychological diseases of nervous system. Further studies by using the discussed tests can be very beneficial for achieving a therapeutic answer to these diseases.

Protective Effects and Mechanism of Radix Polygalae Against Neurological Diseases as Well as Effective Substance

Radix Polygalae (also known as Yuanzhi in China) is the dried rhizome of Polygala tenuifolia Willd. or Polygala sibirica L., which is a famous Chinese herb and has been widely used for centuries in traditional medicines including expectorants, tonics, tranquilizers, antipsychotic, and so on. This article reviews the neuroprotective effects of Radix Polygalae in preclinical models of central nervous system (CNS) disorders, especially anxiety, depression, declining cognition, Alzheimer's disease (AD), and Parkinson's disease (PD). The chemical composition of Radix Polygalae as well as the underlying mechanisms of action were also reviewed. We found that Radix Polygalae possesses a broad range of beneficial effects on the abovementioned conditions. The multifold mechanisms of action include several properties such as antioxidant and associated apoptotic effects; anti-inflammatory and associated apoptotic effects; neurogenesis, regeneration, differentiation, and neuronal plasticity improvement; hypothalamic-pituitary-adrenal axis (HPA) regulation; neurotransmitter release; and receptor activation (A_2AR, NMDA-R, and GluR). Nevertheless, the detailed mechanisms underlying this array of pharmacological effects observed in vitro and in vivo still need further investigation to attain a coherent neuroprotective profile.

Sinapic Acid Alleviates Oxidative Stress and Neuro-Inflammatory Changes in Sporadic Model of Alzheimer's Disease in Rats

The role of oxidative stress, neuro-inflammation and cholinergic dysfunction is already established in the development of Alzheimer's disease (AD). Sinapic acid (SA), a hydroxylcinnamic acid derivative, has shown neuro-protective effects. The current study evaluates the neuro-protective potential of SA in intracerebroventricular streptozotocin (ICV-STZ) induced cognitive impairment in rats. Male Wistar rats were bilaterally injected with ICV-STZ. SA was administered intragastrically once daily for three weeks. Rats were divided into sham, ICV-STZ, STZ + SA (10 mg/kg), STZ + SA (20 mg/kg) and SA per se (20 mg/kg). Behavioral tests were assessed on day 0 and 21 days after STZ. Later, rats were sacrificed for biochemical parameters, pro-inflammatory cytokines, choline acetyltransferase (ChAT) expression and neuronal loss in the CA1 region of the hippocampus. The results showed that SA 20 mg/kg significantly (p < 0.05) improved cognitive impairment as assessed by Morris water maze and passive avoidance tests. SA 20 mg/kg reinstated the altered levels of GSH, MDA, TNF-α and IL-1β in the cortex and hippocampus. STZ-induced decreased expression of ChAT and neuronal loss were also significantly (p < 0.05) improved with SA. Our results showed that SA exhibits neuro-protection against ICV-STZ induced oxidative stress, neuro-inflammation, cholinergic dysfunction and neuronal loss, suggesting its potential in improving learning and memory in patients of AD.

Isolation of Sinapic Acid from Habenaria intermedia D. Don: A New Chemical Marker for the Identification of Adulteration and Substitution

Background:

Vriddhi is one of the Rasayana herbs in Ayurveda broadly used in vitality, strengthening Ayurvedic formulations. To fulfill steeply increased demand and declined supply, tubers have been collected in destructive manner resulting in reduced plant population and pushing the plant in Red list of IUCN endangered species. However, manufacturers are using substitutes and other substandard drugs leading to adulteration which puts the importance of therapeutically rich herbal plants at stake. Lack of chemical markers is the main inability of regulatory authorities for not taking any action against this adulteration.

Objective:

Isolation of chemical marker of plant that can be used as a reference compound for identification of unauthorized substitution.

Methods:

Preliminary phytochemical screening of methanolic and toluene extract of H. intermedia D. Don was done using standard methods followed by column chromatography for the isolation of phytoconstituents. A total of 3004 fractions were collected with Thin Layer Chromatography (TLC) profiling and different fractions were pooled. A single compound was isolated and confirmed by chemical test, melting point, spectral analysis and compared with the literature.

Results:

Phytochemical screening of extracts shows the presence of alkaloids, carbohydrates, steroids, terpenoids, flavonoids, tannins and phenolics. A pure white crystalline powder was isolated by column chromatography which was characterized as 3,5-dimethoxy-4- hydroxycinnamic acid (Sinapic acid) with the help of IR and Mass spectroscopy.

Conclusion:

This is the first report of Sinapic acid as a novel compound from Vriddhi, Habenaria genus and Orchidaceae family. It can be used as a marker for the identification of unauthorized substitution and adulteration claiming the use of Vriddhi.

Astaxanthin ameliorates scopolamine-induced spatial memory deficit via reduced cortical-striato-hippocampal oxidative stress

Alzheimer's disease is characterized by progressive disruption of cholinergic neurotransmission and impaired cognitive functions. In rodents, scopolamine has been used to induce cholinergic dysfunction resulting in cognitive impairments and an increment of oxidative stress in the brain. Here we tested whether oxidative stress can be attenuated via an antioxidant (astaxanthin) to rescue scopolamine-induced spatial memory. For this purpose, we administered either 0.9% saline (control), or scopolamine (SCP), or scopolamine plus astaxanthin (SCP + AST) to Swiss albino mice (ten weeks old; n = 20) for 28 consecutive days and subsequently examined animals' locomotor activity, spatial learning, and memory performance. The mice were then euthanized and prefrontal cortex (PFC), striatum (ST), hippocampus (HP), and liver tissues were assayed for antioxidant enzymes, glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and nitric oxide (NO). The SCP group exhibited impaired spatial learning and significantly altered levels of antioxidant enzymes and NO in the PFC, ST, and HP. In contrast, SCP + AST treatment did not cause spatial learning deficits. Furthermore, this condition also showed unaltered levels of SOD and NO in the ST and HP. Taken together, our results show that scopolamine may interrupt the striatal-hippocampal cholinergic activity resulting in impaired spatial memory. At the same time, these impairments are extinguished with astaxanthin by preventing oxidative damage in the striatal-hippocampal cholinergic neurons. Therefore, we suggest astaxanthin as a potential treatment to slow the onset or progression of cognitive dysfunctions that are elicited by abnormal cholinergic neurotransmission in Alzheimer's disease.

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.

Levocarnitine Improves AlCl3-Induced Spatial Working Memory Impairment in Swiss albino Mice

Background: Aluminum, a neurotoxic substance, causes oxidative stress induced-neurodegenerative diseases. Several lines of evidence suggest that levocarnitine has an antioxidant effect and also plays an important role in beta-oxidation of fatty acids. However, the role of levocarnitine in aluminum-induced neurotoxicity has not been well documented. Here we aimed to investigate the effect of levocarnitine on aluminum chloride (AlCl₃)-induced oxidative stress and memory dysfunction.

Methods: Male Swiss albino mice (n = 30) were treated with either control (saline) or AlCl₃ or AlCl₃ plus levocarnitine or levocarnitine or astaxanthin plus AlCl₃ or astaxanthin alone. The spatial working memory was determined by radial arm maze (RAM). In addition, we measured the lipid peroxidation (MDA), glutathione (GSH), advanced oxidation of protein products (AOPP), nitric oxide (NO) and activity of superoxide dismutase (SOD) in the various brain regions including prefrontal cortex (PFC), striatum (ST), parietal cortex (PC), hippocampus (HIP) hypothalamus (HT) and cerebellum (CB). We used astaxanthin as a standard antioxidant to compare the antioxidant activity of levocarnitine.

Results: The RAM data showed that AlCl₃ treatment (50 mg/kg) for 2 weeks resulted in a significant deficit in spatial learning in mice. Moreover, aluminum exposure significantly (p < 0.05) increased the level of oxidative stress markers such as MDA, GSH, AOPP and NO in the various brain regions compared to the controls. In addition, combined administration of levocarnitine and AlCl₃ significantly (p < 0.05) lowered the MDA, AOPP, GSH and NO levels in mice.

Conclusion: Our results demonstrate that levocarnitine could serve as a potential therapeutic agent in the treatment of oxidative stress associated diseases as well as in memory impairment.

Effects of sinapic acid on hepatic cytochrome P450 3A2, 2C11, and intestinal P-glycoprotein on the pharmacokinetics of oral carbamazepine in rats: Potential food/herb-drug interaction

Dietary supplements, herbal medicines, and other foods may affect the pharmacokinetics and/or pharmacodynamics of carbamazepine (CBZ), which may possibly lead to potential drug-drug/herb-drug interactions, as CBZ has a narrow therapeutic window. Sinapic acid (SA) is a bioactive phytoconstituent used as a dietary supplement for the treatment of epilepsy. This study determined the effects of SA on the pharmacokinetics of CBZ and proposed a possible interaction mechanism in twenty-four male wistar rats (180-210 g). A single CBZ dose (80 mg/kg) was administered orally to rats with or without SA pretreatment (20 mg/kg p.o. per day for 7 days, n = 6). The CBZ concentration in plasma samples was determined by using a sensitive reversed-phase high-performance liquid chromatography assay. The pharmacokinetic parameters were calculated by using non-compartmental analysis. Significance was determined through Dunnett's multiple comparison test or one-way analysis of variance as appropriate; p < 0.05 were considered significant. The change in the pharmacokinetic parameters (C_max, T_max, AUC_0-t, AUC_0-∞, T_½, and k_el) of CBZ was evaluated after the administration of CBZ alone or after CBZ co-administration with SA pretreatment. The plasma concentration of CBZ was higher after SA pretreatment than that without pretreatment. The pharmacokinetics of orally administered CBZ were found to be significantly altered (p < 0.05) in rats pretreated with SA compared to those in rats administered CBZ alone. The increases in the C_max, AUC_0-t, T_1/2, and MRT of CBZ were 29.79%, 57.18%, 77.18%, and 58.31%, respectively, whereas the k_el and apparent oral CL/F were significantly reduced (p < 0.05) in rats pretreated with SA compared to those in rats not pretreated with SA (43.87% and 42.50%, respectively). However, no significant change was observed in the T_max of CBZ in rats pretreated with SA compared to that in rats that did not receive pretreatment. The enhancement in Cmax, AUC_0-t, T_1/2, and MRT and the reduction in K_el and CL/F values resulted from the significant inhibition of CYP3 A2, the CYP2C11-mediated metabolism of CBZ in the liver, and the inhibition of intestinal P-glycoprotein/MDR1, which enhanced the rate of CBZ absorption. Further studies are required to determine the clinical relevance of these observations.

Jia-Wei-Kai-Xin-San, an Herbal Medicine Formula, Ameliorates Cognitive Deficits via Modulating Metabolism of Beta Amyloid Protein and Neurotrophic Factors in Hippocampus of Aβ1-42 Induced Cognitive Deficit Mice

Jia-Wei-Kai-Xin-San (JWKXS) is a Chinese medicine formula applied for treating morbid forgetfulness in ancient China. Today, this formula is frequently applied for Alzheimer's disease and vascular dementia (VD) in clinic. Here, we developed it as granules and aimed to evaluate its anti-AD effect on β amyloid protein 1-42 (Aβ1-42) induced cognitive deficit mice and reveal the possible molecular mechanisms. Firstly, daily intra-gastric administration of chemically standardized of JWKXS granules for 7 days significantly ameliorated the cognitive deficit symptoms and inhibited cell apoptosis in hippocampus on Aβ1-42 injection mice. JWKXS granules significantly decreased Aβ level, increased superoxide dismutase activity and decreased malondialdehyde level in hippocampus of model mice. It also restored acetylcholine amounts, inhibited acetylcholinesterase activities and increased choline acetyltransferase activities. In addition, JWKXS granules enabled the transformation of precursors of NGF and BDNF into mature forms. Furthermore, JWKXS granules could regulate gene expressions related to Aβ production, transportation, degradation and neurotrophic factor transformation, which led to down-regulation of Aβ and up-regulation of NGF and BDNF. These findings suggested that JWKXS granules ameliorated cognitive deficit via decreasing Aβ levels, protecting neuron from oxidation damages and nourishing neuron, which could serve as alternative medicine for patients suffering from AD.

Characterization of UV-Sensitive Marker Constituents of Polygala Root for TLC: Applications in Quality Control of Single Crude Drug Extract Preparations

Polygala Root (the root of Polygala tenuifolia WILLDENOW; Japanese name "Onji"), a well-known crude drug, traditionally used as an expectorant and sedative, has been attracting increased interest in recent years owing to its newly found pharmacological effect related to neuroprotection. However, there is no specific method for identifying and estimating the quality of this crude drug in the Japanese Pharmacopoeia, 17th edition. Therefore, in order to develop a TLC-based simple and convenient identification method using characteristic chemical marker(s) for the drug and its extract products, UV-sensitive constituents of Polygala Root were first investigated. A total of 23 aromatic compounds were isolated and characterized. Two new compounds, namely, polygalaonjisides A (1) and B (2), were characterized as syringic acid 4-O-(2'-O-β-D-apiosyl)-β-D-glucoside and 2-O-(β-D-glucosyl)-3'-O-benzoylsucrose, respectively. Based on these phytochemical results, a TLC method focusing on three marker spots with Rf value of approximately 0.4-0.5 due to tenuifolisides A and B and 3,6'-di-O-sinapoylsucrose was proposed as a simple and convenient test to identify Polygala Root or its single-extract products on the market. The data presented in this paper could be useful in stipulating a confirmation test to identify Polygala Root.

Radix Polygalae Extract Attenuates PTSD-like Symptoms in a Mouse Model of Single Prolonged Stress and Conditioned Fear Possibly by Reversing BAG1

Radix Polygalae (RP) has been used to relieve psychological stress in traditional oriental medicine. Recently, cell protective, antiamnestic and antidepressant-like effects were disclosed but the possible application of RP to post-traumatic stress disorder, in which exaggerated fear memory persists, has not yet been explored. For this purpose, the effects of RP on fear behavior was examined in a mouse model of single prolonged stress and conditioned fear (SPS-CF), previously shown to mimic key symptoms of post-traumatic stress disorder. Male mice received daily oral dose of RP extract or vehicle during the SPS-CF procedure. Then fear-related memory (cohort 1, n=25), non-fear-related memory (cohort 2, n=38) and concentration-dependent effects of RP on fear memory (cohort 3, n=41) were measured in 3 separate cohort of animals. Also working memory and anxiety-like behaviors were measured in cohort 1. RP-treated SPS-CF mice exhibited attenuated contextual but not cued freezing and no impairments in the working memory and spatial reference memory performances relative to vehicle-treated SPS-CF controls. RP-treated SPS-CF and naive mice also demonstrated no difference in anxiety-like behavior levels relative to vehicle-treated SPS-CF and naive controls, respectively. In the hippocampus of SPS-CF mice, expression of BAG1, which regulates the activity of GR, was decreased, whereas RP increased expression of BAG1 in naïve and SPS-CF mice. These results suggest that RP exerts some symptomatic relief in a mouse with exaggerated fear response. RP and its molecular components may thus constitute valuable research targets in the development of novel therapeutics for stress-related psychological disorders.

Features and outcomes of drugs for combination therapy as multi-targets strategy to combat Alzheimer's disease

ETHNOPHARMACOLOGICAL RELEVANCE

Alzheimer's disease (AD), a deleterious neurodegenerative disorder that impairs memory, cognitive functions and may lead to dementia in late stage of life. The pathogenic cause of AD remains incompletely understood and FDA approved drugs are partial inhibitors rather than curative. Most of drugs are synthetic or natural products as galanthamine is an alkaloid obtained from Galanthus spp. Huperzine A, an alkaloid found in Huperzia spp., gingkolides a diterpenoids from Gingko biloba and many ethnobotanicals like Withania somnifera (L.) Dunal., Physostigma venenosum Balf., Bacopa monnieri (L.) Wettst., Centella asiatica (L.) Urb. have been used by traditional Indian, Chinese, and European system of medicines in AD. Clinical significance opioid alkaloid in Papaver somniferum has shown another dimension to this study. Over exploitation of medicinal plants with limited bioactive principles has provided templates to design synthetic drugs in AD e.g. rivastigmine, phenserine, eptastigmine based on chemical structure of physostigmine of Physostigma venenosum Balf. Even ZT-1 a prodrug of Hup A and memogain a prodrug of galantamine has achieved new direction in drug development in AD. All these first-line cholinesterase-inhibitors are used as symptomatic treatments in AD. Single modality of "One-molecule-one-target" strategy for treating AD has failed and so future therapies on "Combination-drugs-multi-targets" strategy (CDMT) will need to address multiple aspects to block the progression of pathogenesis of AD. Besides, cholinergic and amyloid drugs, in this article we summarize proteinopathy-based drugs as AD therapeutics from a variety of biological sources. In this review, an attempt has been made to elucidate the molecular mode of action of various plant products, and synthetic drugs investigated in various preclinical and clinical tests in AD. It also discusses current attempts to formulate a comprehensive CDMT strategy to counter complex pathogenesis in AD.

MATERIALS AND METHODS

Information were collected from classical books on medicinal plants, pharmacopoeias and scientific databases like PubMed, Scopus, GoogleScholar, Web of Science and electronic searches were performed using Cochrane Library, Medline and EMBASE. Also published scientific literatures from Elsevier, Taylor and Francis, Springer, ACS, Wiley publishers and reports by government bodies and documentations were assessed.

RESULTS

60 no. of natural and synthetic drugs have been studied with their significant bioactivities. A decision matrix designed for evaluation of drugs for considering to the hypothetic "CDMT" strategy in AD. We have introduced the scoring pattern of individual drugs and based on scoring pattern, drugs that fall within the scoring range of 18-25 are considered in the proposed CDMT. It also highlights the importance of available natural products and in future those drugs may be considered in CDMT along with the qualified synthetic drugs.

CONCLUSION

A successful validation of the CDMT strategy may open up a debate on health care reform to explore other possibilities of combination therapy. In doing so, it should focus on clinical and molecular relationships between AD and CDMT. A better understanding of these relationships could inform and impact future development of AD-directed treatment strategies. This strategy also involves in reducing costs in treatment phases which will be affordable to a common man suffering from AD.

UPLC Quantitative Analysis of Multi-Components by Single Marker and Quality Evaluation of Polygala tenuifolia Wild. Extracts

The quality control of Polygala tenuifolia Wild. is a major challenge in its clinical application. In this paper, a new strategy for the quality evaluation of P. tenuifolia extracts was verified through reverse-phase ultra-performance liquid chromatography (UPLC). The quantitative analysis of multi-components by a single marker (QAMS) was conducted with 3,6′-disinapoyl sucrose as an internal reference substance. Eight components (i.e., sibiricose A5, sibiricose A6, glomeratose A, tenuifoliside A, tenuifoliside B, tenuifoliside C, sibiricaxanthone B, and polygalaxanthone III) were determined based on the relative correction factors. The concentrations of these components were also determined by applying a conventional external standard method. The cosine value confirmed the consistency of the two methods (cosine ratio value >0.999920). Hierarchical cluster analysis, radar plots, and discriminant analysis were performed to classify 23 batches of P. tenuifolia extracts from Shanxi, Hebei, and Shaanxi in China. Results revealed that QAMS combined with radar plots and multivariate data analysis could accurately measure and clearly distinguish the different quality samples of P. tenuifolia. Hence, QAMS is a feasible and promising method for the quality control of P. tenuifolia.

Stemness and differentiation potential-recovery effects of sinapic acid against ultraviolet-A-induced damage through the regulation of p38 MAPK and NF-κB

Ultraviolet A (UVA) irradiation exerts negative effects on stemness and differentiation potential of stem cells. This study aimed to explore the effect of sinapic acid on UVA-irradiation-induced damages to stemness and differentiation potential of human-adipose-tissue-derived mesenchymal stem cells (hAMSCs) and its UVA-antagonist mechanisms. Sinapic acid attenuated UVA-induced reduction in the proliferative potential and stemness by upregulating OCT4, SOX2, and NANOG. In addition, sinapic acid significantly recovered UVA-induced reduction in expression level of hypoxia-inducible factor (HIF)-1α. The antagonist effect of sinapic acid against stemness damage was mediated by reduceing PGE₂ production through inhibition of p38 MAPK and NF-κB. Moreover, sinapic acid attenuated UVA-induced reduction in differentiation potential by downregulating the expression of macrophage migration inhibitory factor (MIF) and Kruppel-like factor (KLF) 2 gene while activating AMP-activated protein kinase (AMPK). UVA-induced inhibition of adipogenic differentiation was mediated by reducing MIF production through suppression of NF-κB. Taken together, these findings suggest that sinapic acid may ameliorate UVA-irradiation-induced reduced stemness and differentiation potential of hAMSCs. Therefore, sinapic acid might have potential as an antagonist agent to attenuate damages caused by UVA.

Reduced Consolidation, Reinstatement, and Renewal of Conditioned Fear Memory by Repetitive Treatment of Radix Polygalae in Mice

The therapeutic goal for the treatment of posttraumatic stress disorder (PTSD) is to promote extinction and to prevent the relapse of fearful memories. Research has identified pharmacological treatments that may regulate the formation and extinction of fear memories, but not many reagents that block the relapse of extinguished fear are known. Radix Polygalae (RP) is an Asian herb used for sedation, and its ingredients have anxiolytic and antidepressant properties. As various neurological effects have been identified, we tested whether RP affects the relapse of fear. Freezing in response to a conditioned context and cues was used to measure the effects of RP in mice. In cohort 1 (n = 30), consolidation, extinction, and reinstatement were tested during the course of 18 days of treatment. In cohort 2 (n = 30), consolidation, extinction, and renewal were tested during 10 days of treatment. The consolidation, extinction, reinstatement, and possibly the renewal of context-induced freezing were inhibited due to the administration of RP in animal subjects. However, the effects of RP on the freezing responses of subjects elicited by conditioned auditory cues were less obvious. Because it effectively suppresses the consolidation of fear memories, RP may be used for primary and secondary prevention of symptoms in PTSD patients. Additionally, because it effectively suppresses the reinstatement and renewal of fear memories, RP may be applied for the prevention of fear relapse in PTSD patients who have undergone exposure therapy.

WY14643 Attenuates the Scopolamine-Induced Memory Impairments in Mice

WY14643 is a selective agonist of peroxisome proliferator-activated receptor-α (PPAR-α) with neuroprotective and neurotrophic effects. The aim of this study was to evaluate the effects of WY14643 on cognitive impairments induced by scopolamine, a muscarinic acetylcholine receptor antagonist. We conducted different behavior tests including the Y-maze, Morris water maze, and passive avoidance test to measure the cognitive functions of C57BL/6J mice after scopolamine and WY14643 treatment. It was found that WY14643 injection significantly attenuated the scopolamine-induced cognitive impairments in these behavioral tests. Moreover, WY14643 treatment significantly enhanced the expression of brain-derived neurotrophic factor (BDNF) signaling cascade in the hippocampus. The usage of both PPAR-α inhibitor GW6471 and BDNF system inhibitor K252a fully prevented the memory-enhancing effects of WY14643. Therefore, these findings suggest that WY14643 could improve the scopolamine-induced memory impairments, and these effects are mediated by the activation of PPAR-α and BDNF system, thereby exhibiting a cognition-enhancing potential.

Sinapic Acid and Its Derivatives as Medicine in Oxidative Stress-Induced Diseases and Aging

Sinapic acid (3,5-dimethoxy-4-hydroxycinnamic acid) is an orally bioavailable phytochemical, extensively found in spices, citrus and berry fruits, vegetables, cereals, and oilseed crops and is known to exhibit antioxidant, anti-inflammatory, anticancer, antimutagenic, antiglycemic, neuroprotective, and antibacterial activities. The literature reveals that sinapic acid is a bioactive phenolic acid and has the potential to attenuate various chemically induced toxicities. This minireview is an effort to summarize the available literature about pharmacokinetic, therapeutic, and protective potential of this versatile molecule in health related areas.

UPLC-Q-TOF-MS(E) analysis of the constituents of Ding-Zhi-Xiao-Wan, a traditional Chinese antidepressant, in normal and depressive rats

Ding-Zhi-Xiao-Wan (DZXW) is a traditional Chinese medicine widely used for treating depression. To clarify the bioactive constituents of DZXW, a new rapid ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS(E)) method was established in this study, with the whole extract of the formula separated into multiple components to facilitate the analytical process. In total, 97 compounds were detected and 88 were identified in DZXW. Based on their exact masses, fragmentation characteristics, and retention times, 85 of the 88 compounds were confirmed either conclusively or tentatively, and three potentially novel compounds were identified. In addition, following a three-day oral administration of DZXW, 60 and 28 compounds were observed in the plasma of normal and depressive rats, respectively. Finally, by combining our data with pharmacological information, 10 compounds were predicted as the likely bioactive constituents of DZXW as an antidepressant agent. Our approach provided a rapid method for characterising the chemical constituents of DZXW, and we were the first to screen for bioactive indexes in the plasma of depressive rats. Furthermore, our results provide useful chemical information that could be employed for further study of the pharmacodynamic material basis of DZXW's antidepressant effects.

The gastrointestinal irritation of polygala saponins and its potential mechanism in vitro and in vivo

Processing alters the pharmacological activity and reduces the gastrointestinal toxicity of the polygalae. To investigate the effect of processing, different glycosyl substituent products were tested. Hypnotic and subhypnotic doses of pentobarbital-induced sleep tests on mice were used to evaluate the sedative activity of polygala saponins with different glycosyl substituents; isolated gut motility experiment was employed to study excitatory effects of different polygala saponins; the gastrointestinal irritation effects of different polygala saponins were compared by measuring the levels of gastric PGE2 and intestinal TNF-α on mice. When compared with control, Onjisaponin B (OJB) and tenuifolin (TEN), but not senegenin (SNG), significantly increased the number of sleeping mice and prolonged the sleeping time (P < 0.05); 80, 40, and 20 mg/L of OJB and 80 mg/L of TEN, but not SNG, obviously changed the amplitude and frequency of isolated jejunum (P < 0.05); all the three compounds significantly decreased the level of gastric PGE2 but had no obvious influences on the reduction of intestinal TNF-α level. For sedative and hypnotic effects, OJB > TEN > SNG; for the protection form gastrointestinal irritation and damages, OJB > TEN > SNG. Therefore, in processing Polygala, glycosyl breaking may be related to the decline of pharmacological activity and gastrointestinal toxicity of polygala saponins.

Ameliorative effect of rosmarinic acid on scopolamine-induced memory impairment in rats

Rosmarinic acid (RA) is a natural phenol that exerts different biological activities, such as antioxidant activity and neuroprotective effects. In this study, we hypothesized that administration of RA (8, 16, and 32 mg/kg, p.o.) for 7 days would effect on scopolamine-induced cognitive dysfunction as an extensively used model of cognitive impairment. The rats were divided into 10 groups. The acquisition trial was done 1h after the last administration of RA. Animals were divided into control, RA (8, 16, and 32 mg/kg) and donepezil (2 mg/kg) treated controls, scopolamine, RA (8, 16, and 32 mg/kg), and donepezil (2 mg/kg) treated scopolamine groups. Memory impairment was induced by scopolamine treatment (1 mg/kg, i.p.) 30 min after the administration of RA, donepezil, or saline. Scopolamine administration caused cognition deficits in the PAL and memory paradigm. While orally RA administration (16 and 32 mg/kg) improved learning and memory in control rats, it reversed learning and memory deficits of scopolamine received groups. Administration of RA at the dose of 8 mg/kg did not alter cognitive function in control and scopolamine treated groups. The combination of anticholinesterase, neuroprotective, and antioxidant properties of RA may all be responsible for the observed effects. These results indicate the beneficial effects of subchronic RA administration in passive avoidance learning and memory in control rats as well as in a pharmacological model of cholinergic deficit which continue to expand the knowledge base in creating new treatment strategies for cognition deficits and dementia. Of course, further studies are warranted for clinical use of RA in the management of demented subjects.

Tenuifolin, a secondary saponin from hydrolysates of polygalasaponins, counteracts the neurotoxicity induced by Aβ25-35 peptides in vitro and in vivo

Alzheimer's disease (AD) is associated with damage to hippocampal neurons and declines in cognitive functions. The accumulation of amyloid peptides is regarded as a crucial event in the initiation of AD. The neurotoxicity induced by Aβ25-35 peptides was used to screen for cytoprotective factors in vitro, and the cognitive deficits induced by the injection of Aβ25-35 into the hippocampus were used to evaluate effect on learning and memory. Our previous study revealed that hydrolysate of polygalasaponins (HPS) clearly improve the cognitive deficits induced by the injection of Aβ25-35 in mice, but the potential active constituent of HPS remains unclear. The purposes of this study were to separate and purify the secondary saponins of HPS, screen for neuroprotective effects of the constituents in vitro, and to evaluate the effect of cognition in vivo. Various chromatographic methods were used to separate and purify the HPS. The neuroprotective effects were examined in Aβ25-35-damage-induced PC12 cells. The protective effect of tenuifolin on the cognitive impairments induced by Aβ25-35 injection was assessed using the Morris water maze and step-through passive avoidance tests. Tenuifolin and fallaxsaponin A were isolated from the HPS. Tenuifolin possessed neuroprotective effects against Aβ25-35-induced apoptosis in PC12 cells and significantly improved the cognitive deficits induced by the intrahippocampal injection of Aβ25-35 in mice. Thus, tenuifolin is one of the active constituents of HPS against the neurotoxicity induced by Aβ25-35 peptides in vitro and in vivo.

In vitro immunocompetence of two compounds isolated from Polygala tenuifolia and development of resistance against grass carp reovirus (GCRV) and Dactylogyrus intermedius in respective host

The present study was undertaken to isolate some compounds from methanol extract of Polygala tenuifolia and evaluate their immunostimulatory properties and antiviral activity using grass carp Ctenopharyngodon idella kidney (CIK) cells and GCRV. By applying insecticidal bioassay-guided, chromatography techniques and successive recrystallization, two purified compounds were obtained. The changes of expression of selected immune genes (Mx1, IL-1β, TNFα, MyD88 and IgM) in C. idella kidney cell lines were evaluated after exposure to these isolated compounds. The results showed that compound 1 and 2 up-regulated to varying degrees of Mx1, IL-1β, TNFα, and MyD88 in C. idella kidney cells. WST-8 kit assay verified the two compounds has no toxic effects on CIK cell, and furthermore, have in vitro antivirus activity. Especially, that there is keeping 79% cell viability when exposure to compound 2 (100 mg L(-1)). According to in vivo insecticidal assays against Dactylogyrus intermedius, compound 2 exhibited higher efficacy than compound 1, which was found to be 87.2% effective at the concentrations of 5 mg L(-1) and safe to goldfish (Carassius auratus). Besides, the purified compounds were identified by spectral data as: (1) 1,5-Anhydro-D-glucitol and (2) 3,4,5-trimethoxy cinnamic acid. Overall, the results indicate that bath administration of these compounds modulates the immune related genes in C. idella kidney cells and to some extent, eliminate the virus and parasitic infections.

Comparison of Two Old Phytochemicals versus Two Newly Researched Plant-Derived Compounds: Potential for Brain and Other Relevant Ailments

Among hundreds of formulae of Chinese herbal prescriptions and recently extracted active components from the herbs, some of which had demonstrated their functions on nervous system. For the last decade or more, Gingko biloba and Polygala tenuifolia were widely studied for their beneficial effects against damage to the brain. Two compounds extracted from Apium graveolens and Rhizoma coptidis, butylphthalide and berberine, respectively, received much attention recently as potential neuroprotective agents. In this review, the two traditionally used herbs and the two relatively new compounds will be discussed with regard to their potential advantages in alleviating brain and other relevant ailments.

Preclinical evidence of rapid-onset antidepressant-like effect in Radix Polygalae extract

Radix Polygalae (the root of Polygala tenuifolia) is a herb widely used in traditional Asian medicine that is thought to exert a variety of neuropsychiatric effects. Radix Polygalae extract can protect against N-methyl D-aspartate (NMDA) neurotoxicity and induce brain-derived neurotrophic factor (BDNF) expression, suggesting modulatory roles at glutamatergic synapses and possible antidepressant action. In accordance with this hypothesis, Radix Polygalae extract demonstrated antidepressant-like effects in 8-week-old male C57Bl/6 mice by decreasing behavioral despair in the forced swim and tail suspension tasks and increasing hedonic-like behavior in the female urine sniffing test 30 minutes after a single oral administration of 0.1 mg/kg. Reduced latency to acquire a food pellet in the novely suppressed feeding paradigm, without change in anxiety-like behaviors suggested a rapid-onset nature of the antidepressant-like effect. In addition, it decreased the number of failed escapes in the learned helplessness paradigm after two oral administrations 24 hours and 30 minutes before the first test. Finally, it reversed anhedonia as measured by saccharin preference in mice exposed to the chronic stress model after two administrations of 0.1 mg/kg, in contrast to the repeated administration generally needed for similar effect by monoamergic antidepressants. Immobility reduction in tail suspension task was blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist NBQX, a pattern previously demonstrated by ketamine and other ketamine-like rapid-onset antidepressants. Also similarly to ketamine, Radix Polygalae appeared to acutely decrease phosphorylation of GluR1 serine-845 in the hippocampus while leaving the phosphorylation of hippocampal mTOR serine 2448 unchanged. These findings serve as preclinical evidence that Radix Polygalae extract exerts rapid-onset antidepressant effects by modulating glutamatergic synapses in critical brain circuits of depression and may be worthy of further evaluation as a safe substitute to other rapid-onset antidepressants known to have unacceptable side effects.

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.

Tenuigenin protects dopaminergic neurons from inflammation-mediated damage induced by the lipopolysaccharide

BACKGROUND

Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive death of dopaminergic neurons in the substantia nigra pars compacta (SNpc).

AIMS

To study if tenuigenin (TEN), the main active component of Polygala tenuifolia, can protect dopaminergic neurons from inflammation-mediated damage in vivo.

METHODS

We observed the effects of TEN on lipopolysaccharide (LPS) induced PD model by behavioral analysis, high-performance liquid chromatography, immunohistochemistry and enzyme-linked immunoadsorbent assay, etc.

RESULTS

We showed that a single intranigral dose of LPSs (10 μg) induced microglial activation, reduced the survival ratio of tyrosine hydroxylase-immunoreactive (TH-ir) neurons in the SNpc and reduced dopamine (DA) content in the striatum. Treatment with 300 mg/kg TEN once per day over 14 weeks improved the survival rate of TH-ir neurons in the SNpc to 75%, on the non-injected side. Treatment with 200 or 300 mg/kg TEN once per day over 14 weeks significantly improved DA levels in the striatum to 73% and 81% on the non-injected side, respectively. The excessive production of cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, was abolished by TEN administration.

CONCLUSION

Our results suggest that TEN may play a role in protecting dopaminergic neurons against inflammatory challenge.

Tenuigenin ameliorates learning and memory impairments induced by ovariectomy

Estrogen deficiency is associated with cognitive impairment. Hormone replacement therapy (HRT) has proven to be effective in preventing and reversing the memory and learning deficiencies. However, conventional estrogenic treatment could increase the risks of breast cancer and venous thromboembolism. Tenuigenin (TEN) is putatively believed as the active component extracted from a Chinese herb Polygala tenuifolia root. Although TEN has been shown to enhance learning and memory in healthy mice, it remains unknown whether or not TEN could ameliorate learning and memory impairments. In the present study, mice were divided into four groups: sham-operated (sham), ovariectomized (OVX), OVX+estradiol benzoate (EB) and OVX+TEN groups. Step-through passive avoidance and Y-maze tests were used to assess learning and memory abilities, and the number of nitric oxide synthase (NOS) positive neurons and the synaptic measurement of hippocampal CA1 area were examined. The results showed that TEN was given orally to OVX mice, leading to the improvement of learning and memory in step-through passive avoidance and Y-maze tests. TEN could reduce the loss of NOS positive neurons and prevent the synaptic morphological changes induced by ovariectomy. Our results suggest that TEN may exert a potential therapeutic value for menopause cognitive dysfunction.

Tenuigenin treatment improves behavioral Y-maze learning by enhancing synaptic plasticity in mice

Polygala tenuifolia root has been used to improve memory and cognitive function in Traditional Chinese Medicine for more than 2000 years. Since tenuigenin (TEN) is one of the most utilized P. tenuifolia root extracts, it is surprising there is no evidence for the effects of TEN on learning and memory so far. In the present study, we investigated the effects of TEN on learning and memory with Y-maze test in mice. We found that oral administration of 4mg/kg TEN significantly improved learning and memory in Y-maze task. Treatment with 4mg/kg TEN markedly reduced the acetylcholinesterase (AChE) activity and malondialdehyde (MDA) level, and increased superoxide dismutase (SOD) activity in hippocampus. In the electrophysiological test of hippocampal brain slice, 2μg/ml TEN perfusion substantially enhanced field excitatory postsynaptic potential (fEPSP) amplitude both in basic synaptic transmission and after high frequency stimulation (HFS) in Schaffer to CA1 pathway (Scha-CA1). These results indicate that TEN enhancing learning and memory may result from inhibiting AChE activity, improving antioxidation and enhancing synaptic plasticity in mice. Therefore, TEN shows promise as a potential nootropic product in improving learning and memory.

Angelica keiskei ameliorates scopolamine-induced memory impairments in mice

Memory impairment is the most common symptom in patients with Alzheimer's disease (AD). Angelica keiskei (AK) has traditionally been used as a diuretic, laxative, analeptic and galactagogue. However, the anti-amnesic effects of AK and its molecular mechanisms have yet to be clearly elucidated. The aim of the present study is to evaluate the effects of AK on scopolamine-induced memory impairments in mice. The regulatory effect of AK on memory impairment was investigated using passive avoidance, Y-maze and the Morris water maze tasks. Acetylcholinesterase (AChE) activity assay was performed to investigate the cholinergic antagonistic effect of AK in the hippocampus. The effect of AK on phosphorylation of cAMP response element-binding protein (CREB) and expression of brain-derived neurotrophic factor (BDNF) were evaluated by Western blot assays and immunohistochemistry. The findings showed that AK significantly attenuated scopolamine-induced cognitive impairment in mice. Increase of AChE activity caused by scopolamine was significantly attenuated by AK. Additionally, AK significantly recovered the phosphorylation of CREB and expression of BDNF reduced by scopolamine in the hippocampus. Taken together, these results provide experimental evidence that AK might be a useful agent in preventing deficit of learning and memory caused by AD and aging.

Promising therapeutics with natural bioactive compounds for improving learning and memory--a review of randomized trials

Cognitive disorders can be associated with brain trauma, neurodegenerative disease or as a part of physiological aging. Aging in humans is generally associated with deterioration of cognitive performance and, in particular, learning and memory. Different therapeutic approaches are available to treat cognitive impairment during physiological aging and neurodegenerative or psychiatric disorders. Traditional herbal medicine and numerous plants, either directly as supplements or indirectly in the form of food, improve brain functions including memory and attention. More than a hundred herbal medicinal plants have been traditionally used for learning and memory improvement, but only a few have been tested in randomized clinical trials. Here, we will enumerate those medicinal plants that show positive effects on various cognitive functions in learning and memory clinical trials. Moreover, besides natural products that show promising effects in clinical trials, we briefly discuss medicinal plants that have promising experimental data or initial clinical data and might have potential to reach a clinical trial in the near future.

Neuroprotective effect of sinapic acid in a mouse model of amyloid β(1-42) protein-induced Alzheimer's disease

Sinapic acid (SA) is a phenylpropanoid compound with anti-inflammatory and neuroprotective activities. The neuroprotective effects of SA in a mouse model of amyloid β (Aβ)(1-42) protein-induced Alzheimer's disease (AD) were investigated. Mice received a bilateral injection of Aβ(1-42) protein into the hippocampus to verify the efficacy of SA. Mice were treated with SA (10mg/kg/day, p.o.) for 7days beginning immediately after Aβ(1-42) protein injection, and an acquisition trial of the passive avoidance task was conducted 1h after the last administration of SA. Retention trial was conducted 24h after the acquisition trial, and mice were sacrificed for immunohistochemistry immediately after the retention trial. SA rescued neuronal cell death in the hippocampal CA1 region and also attenuated the increase of iNOS expression, glial cell activations and nitrotyrosine expressions induced by Aβ(1-42) protein. SA significantly attenuated memory impairment in the passive avoidance task. These results suggest that SA ameliorated Aβ(1-42) protein-related pathology including neuronal cell death and cognitive dysfunction via its anti-oxidative and anti-inflammatory activities, and may be an efficacious treatment for AD.

Characterization of the metabolism of sibiricaxanthone F and its aglycone in vitro by high performance liquid chromatography coupled with Q-trap mass spectrometry

To explain the low bioavailability of sibiricaxanthone F (SF) following oral administration and to predict its possible metabolites in vivo, the in vitro biotransformation of SF and its metabolic stability in intestinal bacteria (BI) were studied. The metabolism of SF and its aglycone (1,3,6-trihydroxy-2,7-dimethoxyxanthone, Xan) was characterized after incubation with human and rat liver microsomes (HLMs and RLMs). The chemical structures of the metabolites were tentatively identified on the basis of their mass profiles using high performance liquid chromatography coupled with an enhanced mass spectrometry-information dependent acquisition-enhanced product ion (EMS-IDA-EPI) scan mode on a hybrid triple quadrupole-linear ion trap mass spectrometer. The metabolic stability of SF in BI was determined using the multiple reaction monitoring (MRM) mode. As a result, five hydrolyzed metabolites (M1-M4 and Xan) were generated stepwise for SF when it was incubated with BI, whereas two demethylated products (M1 and M5) were detected for Xan in BI. The metabolic stability study of SF in BI revealed that the parent compound could be rapidly hydrolyzed by BI and that Xan, the main corresponding metabolite, increased rapidly. In RLMs and HLMs, two hydrolyzed metabolites (M2 and M3) mediated by CYP450 isoenzymes appeared for SF in the presence of an NADPH-regenerating system, whereas no metabolite was detected for Xan under the same conditions. One (M6) and three glucuronidated metabolites (M7-M9) were generated from SF and Xan, respectively, by phase II isoenzymes in liver microsomal proteins in the presence of uridine 5'-diphosphoglucuronic acid (UDPGA). Overall, the present study revealed that extensive first-pass elimination occurred for SF in intestinal bacteria and hepatic subcellular proteins in vitro, which could be one of the main reasons for the low bioavailability of SF; furthermore, the possible SF-related metabolites in rats and humans were elucidated to be mono-glucuronidated derivatives of Xan following oral administration of SF.

Effects of lavender oil inhalation on improving scopolamine-induced spatial memory impairment in laboratory rats

Lavender is reported to be an effective medical plant in treating inflammation, depression, stress and mild anxiety in Europe and the USA. The present study investigated the effects of two different lavender essential oils from Lavandula angustifolia ssp. angustifolia Mill. (Lamiaceae) and Lavandula hybrida Rev. (Lamiaceae) on neurological capacity of male Wistar rats subjected to scopolamine (0.7mg/kg)-induced dementia rat model. Chronic exposures to lavender essential oils (daily, for 7 continuous days) significantly reduced anxiety-like behavior and inhibited depression in elevated plus-maze and forced swimming tests, suggesting anxiolytic and antidepressant activity. Also, spatial memory performance in Y-maze and radial arm-maze tasks was improved, suggesting positive effects on memory formation. Taken together, multiple exposures to lavender essential oils could effectively reverse spatial memory deficits induced by dysfunction of the cholinergic system in the rat brain and might provide an opportunity for management neurological abnormalities in dementia conditions.

Traditional chinese medicine for senile dementia

Traditional Chinese Medicine (TCM) has a 3000 years' history of human use. A literature survey addressing traditional evidence from human studies was done, with key result that top 10 TCM herb ingredients including Poria cocos, Radix polygalae, Radix glycyrrhizae, Radix angelica sinensis, and Radix rehmanniae were prioritized for highest potential benefit to dementia intervention, related to the highest frequency of use in 236 formulae collected from 29 ancient Pharmacopoeias, ancient formula books, or historical archives on ancient renowned TCM doctors, over the past 10 centuries. Based on the history of use, there was strong clinical support that Radix polygalae is memory improving. Pharmacological investigation also indicated that all the five ingredients mentioned above can elicit memory-improving effects in vivo and in vitro via multiple mechanisms of action, covering estrogen-like, cholinergic, antioxidant, anti-inflammatory, antiapoptotic, neurogenetic, and anti-Aβ activities. Furthermore, 11 active principles were identified, including sinapic acid, tenuifolin, isoliquiritigenin, liquiritigenin, glabridin, ferulic acid, Z-ligustilide, N-methyl-beta-carboline-3-carboxamide, coniferyl ferulate and 11-angeloylsenkyunolide F, and catalpol. It can be concluded that TCM has a potential for complementary and alternative role in treating senile dementia. The scientific evidence is being continuously mined to back up the traditional medical wisdom.

Protection of SH-SY5Y neuronal cells from glutamate-induced apoptosis by 3,6'-disinapoyl sucrose, a bioactive compound isolated from Radix Polygala

The neuroprotective effects of 3,6'-disinapoyl sucrose (DISS) from Radix Polygala against glutamate-induced SH-SY5Y neuronal cells injury were evaluated in the present study. SH-SY5Y neuronal cells were pretreated with glutamate (8 mM) for 30 min followed by cotreatment with DISS for 12 h. Cell viability was determined by (3,4,5-dimethylthiazol-2-yl)-2,5-diphenylte-trazolium bromide (MTT) assay, and apoptosis was confirmed by cell morphology and flow cytometry assay, evaluated with propidium iodide dye. Treatment with DISS (0.6, 6, and 60 μmol/L) increased cell viability dose dependently, inhibited LDH release, and attenuated apoptosis. The mechanisms by which DISS protected neuron cells from glutamate-induced excitotoxicity included the downregulation of proapoptotic gene Bax and the upregulation of antiapoptotic gene Bcl-2. The present findings indicated that DISS exerts neuroprotective effects against glutamate toxicity, which might be of importance and contribute to its clinical efficacy for the treatment of neurodegenerative diseases.

Cognitive-enhancing effects of polygalasaponin hydrolysate in aβ(25-35)-induced amnesic mice

Polygalasaponins are the major active constituents of Polygala tenuifolia exhibiting antiamnesic activity, but their applications are limited due to their toxicities. Evidence showed that the toxicities can be attenuated by hydrolysis. Herein, effects of a hydrolysate of polygalasaponins (HPS) on cognitive impairment induced by Aβ₂₅₋₃₅ were assessed by Morris water maze and step-through passive avoidance tests. The impaired spatial reference memory was improved by HPS (50 and 100 mg/kg). In the acquisition trial of step-through test, HPS (50 and 100 mg/kg) increased the latency into the dark chamber and decreased the error frequency significantly (P < .05). However, no significant change was observed during the retention trial. Additionally, HPS increased the corresponding SOD activities (62.34%, 22.09%) and decreased MDA levels (28.21%, 32.35%) in both cortex and hippocampus as compared to model animals. These results show that HPS may be a useful treatment against amnesia probably via its antioxidant properties.