Proof of the mysterious efficacy of ginseng: basic and clinical trials: effects of red ginseng on learning and memory deficits in an animal model of amnesia

Alzheimer's disease treatment: The share of herbal medicines

One of the most frequent forms of dementia in neurological disorders is Alzheimer's disease (AD). It is a chronic neurodegenerative disease characterized by impaired learning and memory. Pathological symptoms as extracellular amyloid-beta (Aβ) plaques and intracellular accumulation of neurofibrillary tangles occur in AD. Due to the aging of the population and increased prevalence of AD, discovery of new therapeutic agents with the highest effectiveness and fewer side effect seems to be necessary. Numerous synthetic medicines such as tacrine, donepezil, galantamine, rivastigmine, memantine, glutathione, ascorbic acid, ubiquinone, ibuprofen, and ladostigil are routinely used for reduction of the symptoms and prevention of disease progression. Nowadays, herbal medicines have attracted popular attention for numerous beneficial effects with little side effects. Lavandula angustifolia, Ginkgo biloba, Melissa officinalis, Crocus sativus, Ginseng, Salvia miltiorrhiza, and Magnolia officinalis have been widely used for relief of symptoms of some neurological disorders. This paper reviews the therapeutic effects of phytomedicines with prominent effects against various factors implicated in the emergence and progression of AD.

SQUAMOSA Promoter Binding Protein-Like (SPL) Gene Family: TRANSCRIPTOME-Wide Identification, Phylogenetic Relationship, Expression Patterns and Network Interaction Analysis in Panax ginseng C. A. Meyer

: SPL (SQUAMOSA promoter binding protein-like) gene family is specific transcription factor in the plant that have an important function for plant growth and development. Although the SPL gene family has been widely studied and reported in many various plant species from gymnosperm to angiosperm, there are no systematic studies and reports about the SPL gene family in Panax ginseng C. A. Meyer. In this study, we conducted transcriptome-wide identification, evolutionary analysis, structure analysis, and expression characteristics analysis of SPL gene family in Panax ginseng by bioinformatics. We annotated the PgSPL gene family and found that they might involve in multiple functions including encoding structural proteins, but the main function were still focused on the binding function. The result showed that 106 PgSPL transcripts were classified into two clades - A and B, both of which respectively consisted of three groups. Besides, we profiled PgSPL transcripts' genotypic, temporal, and spatial expression characteristics. Furthermore, we calculated the correlation of PgSPL transcripts in the 14 tissues of a 4 years old ginseng and 42 farmers' cultivars farmers' cultivars of 4 years old ginsengs' roots with both results showing that SPL transcripts formed a single network, which indicated that PgSPLs inter-coordinated when performing their functions. What's more, we found that most PgSPL transcripts tended to express in older ginseng instead of younger ginseng, which was not only reflected in the expression of more types of SPL transcripts in older ginseng, but also in the higher expression of SPL transcripts in older ginseng. Additionally, we found that four PgSPL transcripts were only massively expressed in roots. According to PgSPL transcripts' expression characteristics, we found that PgSPL23-35 and PgSPL24-09 were most proper two transcripts to further study as ginseng age's molecular marker. These results provide the basis for further elucidation of the PgSPL transcripts' biological function in ginseng and ginseng genetics improvement and gene breeding in the future.

Red ginseng monograph

Ginseng has been traditionally used for several millennia in Asian countries, including Korea, China, and Japan, not only as a nourishing and tonifying agent but also as a therapeutic agent for a variety of diseases. In recent years, the various effects of red ginseng including immunity improvement, fatigue relief, memory improvement, blood circulation improvement, antioxidation, mitigation of menopausal women's symptoms, and anticancer an effect have been reported in clinical as well as basic research. Around the world, there is a trend of the rising consumption of health functional foods on the level of disease prevention along with increased interest in maintaining health because of population aging and the awareness of lifestyle diseases and chronic diseases. Red ginseng occupies an important position as a health functional food. But till now, international ginseng monographs including those of the World Health Organization have been based on data on white ginseng and have mentioned red ginseng only partly. Therefore, the red ginseng monograph is needed for component of red ginseng, functionality certified as a health functional food in the Korea Food and Drug Administration, major efficacy, action mechanism, and safety. The present red ginseng monograph will contribute to providing accurate information on red ginseng to agencies, businesses, and consumers both in South Korea and abroad.

Ginsenoside-Rb3 protects the myocardium from ischemia-reperfusion injury via the inhibition of apoptosis in rats

Ginsenoside-Rb3 (G-Rb3) has been previously demonstrated to attenuate myocardial ischemia-reperfusion injury (MIRI). The aim of the present study was to investigate this further and determine whether G-Rb3 protects the myocardium from ischemia-reperfusion injury via the inhibition of apoptosis. Adult male Sprague Dawley rats were randomly divided into four groups: Sham, MIRI, G-Rb3 treatment (orally, 20 mg/kg) and ischemic postconditioning (as the positive control). The drug or placebo treatment was administered to the rats once a day for three consecutive days, and MIRI was then induced by subjecting the rats to left anterior descending coronary artery ligation for 30 min and reperfusion for 2 h. The results showed that G-Rb3 treatment significantly reduced the number of apoptotic cells in the myocardium and the expression of B-cell lymphoma 2-associated X protein, and increased the expression of B-cell lymphoma 2. The activities of aspartate aminotransferase, lactate dehydrogenase and creatine kinase-MB in the serum were also reduced significantly by the G-Rb3 treatment. These findings suggest that G-Rb3 inhibits apoptosis in the early stage of MIRI, and attenuates MIRI when the reperfusion continues. G-Rb3 was also shown to significantly reduce the level of malondialdehyde and increase the activity of superoxide dismutase in the myocardium, which suggests that attenuating reactive oxygen species accumulation and oxidative stress may be the major mechanism underlying the anti-apoptotic effects of G-Rb3. The release of inflammatory factors was significantly attenuated by G-Rb3, which may also be associated with its anti-apoptotic effects.

Discovery, synthesis, and structure-activity relationships of 20(S)-protopanaxadiol (PPD) derivatives as a novel class of AMPKα2β1γ1 activators

Adenosine 5'-monophosphate-activated protein kinase (AMPK) has been demonstrated as a promising drug target due to its regulatory function in glucose and lipid metabolism. 20(S)-protopanoxadiol (PPD) was firstly identified from high throughput screening as a small molecule activator of AMPK subtype α2β1γ1. In order to enhance its potency on AMPK, a series of PPD derivatives were synthesized and evaluated. Structure-activity relationship study showed that the amine derivatives at the 24-position (groups I-VI) can improve the potency (EC50: 0.7-2.3 μM) and efficacy (fold: 2.5-3.8). Among them, compounds 12 and 13 exhibited the best potency (EC50: 1.2 and 0.7 μM) and efficacy (fold: 3.7 and 3.8). Further study suggested the mechanism of AMPK activation may functioned at the allosteric position, resulting the inhibition of the lipid synthesis in HepG2 cell model.

Protective effect of Panax quinquefolium 20(S)-protopanaxadiol saponins, isolated from Pana quinquefolium, on permanent focal cerebral ischemic injury in rats

Oxidative stress is significant in the pathogenesis of cerebral ischemia. Panax quinquefolium 20(S)-protopanaxadiol saponins (PQDS) have been demonstrated to exhibit a variety of biological effects in the cardiovascular system as a result of their antioxidant properties. However, little is known regarding the effect of PQDS on cerebral ischemia. The purpose of this study was to investigate whether PQDS exhibited protective effects against cerebral ischemia. A model of cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) in Sprague-Dawley rats. Adult male rats were randomly divided into five groups: Sham, MCAO and PQDS treatment groups at doses of 12.5, 25.0 and 50.0 mg/kg. The effects of PQDS on neurological deficits, cerebral infarct area, brain water content, and the malondialdehyde (MDA) and Ca²⁺ levels and Na⁺-K⁺-ATPase and superoxide dismutase (SOD) activities in the brain tissue were analyzed, and the nitric oxide (NO) content and nitric oxide synthase (NOS) activity in the serum were evaluated. Moreover, the expression of Bcl-2 was analyzed using western blotting. Pretreatment with PQDS (25.0 and 50.0 mg/kg) significantly reduced the neurological deficit score, decreased the infarcted area and decreased the brain water content from 83.09 to 80.27% (P<0.05). In addition, PQDS pretreatment decreased the NOS activity and the NO levels in the serum compared with those in the MCAO group. Furthermore, pretreatment with PQDS (25.0 and 50.0 mg/kg) significantly increased the activities of SOD and Na⁺-K⁺-ATPase and decreased the levels of Ca²⁺ and MDA in the brain tissue (P<0.05) compared with those in the MCAO group. Pretreatment with PQDS (25.0 and 50.0 mg/kg) also increased the protein expression level of Bcl-2 compared with that in the MCAO group. The histopathological results demonstrated the protective effect of PQDS on ischemic injury. The results indicated that PQDS has protective effects against ischemic injury in rats. The mechanism may be associated with the inhibition of oxidative stress and apoptosis.

LC-MS-based metabolomic analysis of serum and livers from red ginseng-fed rats

Serum and liver metabolites in rats fed red ginseng (RG) were analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The mass data were analyzed by partial least squares-discriminant analysis (PLS-DA) to discriminate between control and RG groups and identify metabolites contributing to this discrimination. The RG group was clearly separated from the control group on PLS-DA scores plot for serum samples, but not liver samples. The major metabolites contributing to the discrimination included lipid metabolites (lysophosphatidylcholine, acyl-carnitine, and sphingosine), isoleucine, nicotinamide, and corticosterone in the serum; the blood levels of all but isoleucine were reduced by RG administration. Not all metabolites were positively correlated with the health benefits of RG. However, the blood levels of lysophosphatidylcholine, which stimulate various diseases, and long-chain acylcarnitines and corticosterone, which activate the stress response, were reduced by RG, suggesting long-term RG might relieve stress and prevent physiological and biological problems.

Actoprotective effect of ginseng: improving mental and physical performance

Actoprotectors are preparations that increase the mental performance and enhance body stability against physical loads without increasing oxygen consumption. Actoprotectors are regarded as a subclass of adaptogens that hold a significant capacity to increase physical performance. The focus of this article is studying adaptogen herbs of genus Panax (P. ginseng in particular) and their capabilities as actoprotectors. Some animal experiments and human studies about actoprotective properties of genus Panax attest that P. ginseng (administered as an extract) significantly increased the physical and intellectual work capacities, and the data provided suggests that ginseng is a natural source of actoprotectors. Preparations of ginseng can be regarded as potential actoprotectors which give way to further research of its influence on physical and mental work capacity, endurance and restoration after exhaustive physical loads while compared with reference actoprotectors.

20(S)-Protopanaxadiol (PPD) analogues chemosensitize multidrug-resistant cancer cells to clinical anticancer drugs

Novel 20(S)-protopanoxadiol (PPD) analogues were designed, synthesized, and evaluated for the chemosensitizing activity against a multidrug resistant (MDR) cell line (KBvcr) overexpressing P-glycoprotein (P-gp). Structure-activity relationship analysis showed that aromatic substituted aliphatic amine at the 24-positions (groups V) effectively and significantly sensitized P-gp overexpressing multidrug resistant (MDR) cells to anticancer drugs, such as docetaxel (DOC), vincristine (VCR), and adriamycin (ADM). PPD derivatives 12 and 18 showed 1.3-2.6 times more effective reversal ability than verapamil (VER) for DOC and VCR. Importantly, no cytotoxicity was observed by the active PPD analogues (5μM) against both non-MDR and MDR cells, suggesting that PPD analogues serve as novel lead compounds toward a potent and safe resistance modulator. Moreover, a preliminary mechanism study demonstrated that the chemosensitizing activity of PPD analogues results from inhibition of P-glycoprotein (P-gp) overexpressed in MDR cancer cells.

Red ginseng extract attenuates kainate-induced excitotoxicity by antioxidative effects

This study investigated the neuroprotective activity of red ginseng extract (RGE, Panax ginseng, C. A. Meyer) against kainic acid- (KA-) induced excitotoxicity in vitro and in vivo. In hippocampal cells, RGE inhibited KA-induced excitotoxicity in a dose-dependent manner as measured by the MTT assay. To study the possible mechanisms of the RGE-mediated neuroprotective effect against KA-induced cytotoxicity, we examined the levels of intracellular reactive oxygen species (ROS) and [Ca²⁺]_i in cultured hippocampal neurons and found that RGE treatment dose-dependently inhibited intracellular ROS and [Ca²⁺]_i elevation. Oral administration of RGE (30 and 200 mg/kg) in mice decreased the malondialdehyde (MDA) level induced by KA injection (30 mg/kg, i.p.). In addition, similar results were obtained after pretreatment with the radical scavengers Trolox and N, N′-dimethylthiourea (DMTU). Finally, after confirming the protective effect of RGE on hippocampal brain-derived neurotropic factor (BDNF) protein levels, we found that RGE is active compounds mixture in KA-induced hippocampal mossy-fiber function improvement. Furthermore, RGE eliminated 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, and the IC₅₀ was approximately 10 mg/ml. The reductive activity of RGE, as measured by reaction with hydroxyl radical (^•OH), was similar to trolox. The second-order rate constant of RGE for ^•OH was 3.5–4.5 × 10⁹ M⁻¹·S⁻¹. Therefore, these results indicate that RGE possesses radical reduction activity and alleviates KA-induced excitotoxicity by quenching ROS in hippocampal neurons.

Neurologic effects of exogenous saccharides: a review of controlled human, animal, and in vitro studies

OBJECTIVES

Current research efforts are centered on delineating the novel health benefits of naturally derived saccharides, including growing interest in their abilities to influence neurologic health. We performed a comprehensive review of the literature to consolidate all controlled studies assessing various roles of exogenous saccharide compounds and polysaccharide-rich extracts from plants, fungi, and other natural sources on brain function, with a significant focus on benefits derived from oral intake.

METHODS

Studies were identified by conducting electronic searches on PubMed and Google Scholar. Reference lists of articles were also reviewed for additional relevant studies. Only articles published in English were included in this review.

RESULTS

Six randomized, double-blind, placebo-controlled clinical studies were identified in which consumption of a blend of plant-derived polysaccharides showed positive effects on cognitive function and mood in healthy adults. A separate controlled clinical study observed improvements in well-being with ingestion of a yeast beta-glucan. Numerous animal and in vitro studies have demonstrated the ability of individual saccharide compounds and polysaccharide-rich extracts to modify behavior, enhance synaptic plasticity, and provide neuroprotective effects.

DISCUSSION

Although the mechanisms by which exogenous saccharides can influence brain function are not well understood at this time, the literature suggests that certain naturally occurring compounds and polysaccharide-rich extracts show promise, when taken orally, in supporting neurologic health and function. Additional well-controlled clinical studies on larger populations are necessary, however, before specific recommendations can be made.

Ginsenoside Rg3 promotes beta-amyloid peptide degradation by enhancing gene expression of neprilysin

Objectives

It has been hypothesized that the accumulation of beta-amyloid peptide (Aβ) in the brain is a triggering event leading to the pathological cascade of Alzheimer's disease. The steady-state levels of Aβ are determined by the metabolic balance between anabolic and catabolic activity and the dysregulation of this activity leads to Alzheimer's disease. Recent evidence has shown that neprilysin (NEP) is the rate-limiting enzyme in the Aβ degradation in the brain. Ginseng, the root of Panax ginseng C.A. Meyer, is widely used as a tonic for the prevention and treatment of age-related disorders in China. We aimed to investigate the basis of this use.

Methods

In this study, we investigated the effect of ginsenoside Rg3, one of the major active components of ginseng, on the metabolism of Aβ40 and Aβ42 in SK-N-SH cells transfected with Swedish mutant β-amyloid precursor protein (SweAPP).

Results

The ELISA result showed that Rg3 significantly reduced the levels of Aβ40 and Aβ42, 19.65 ± 6.05%, 23.61 ± 6.74%, respectively (P &lt; 0.01). The Western blot analysis showed that Rg3 reduced the levels of Aβ40 and Aβ42 through enhancing NEP gene expression, and real-time PCR assay showed that 50 μM Rg3 could significantly enhance NEP gene expression (2.9 fold at 48 h).

Conclusions

Our findings suggest that the Rg3 compound of ginseng may be useful for treating patients suffering with Alzheimer's disease.

Panax Ginseng in combination with brewers' yeast (Gerivet) as a stimulant for geriatric dogs: a controlled-randomized blinded study

The study was performed on two groups of dogs, one (n = 41) given Ginseng (Panax Ginseng) together with brewers' yeast (Saccharomyces cerevisae) and the other (n = 39) given only brewers' yeast (control group, but not a true placebo), for 8 weeks. Using a questionnaire and three visual analogue scales, the blinded owners evaluated the dogs before the trial, weekly for the 8 weeks of the trial and twice, at 12th and 16th weeks, after the trial (follow-up). At 8th, 12th and 16th weeks the owners also answered questions concerning what treatment their dogs likely had been getting, willingness to continue medication and the dogs' general status. The changes from baseline to the end of the treatment period in the variable scores were calculated for each dog and used in statistics. Panax Ginseng plus yeast significantly improved all evaluated variables within the group. Four of the seven primary (mentally) outcome measures were significant when comparing the changes in the Ginseng group with the control group, and six of the seven were significant when compared to an external group. As the secondary (physical) outcome measures were significantly better in both the Ginseng and the control group compared to the external group, it indicates that brewers' yeast is the ingredient that has impact on physical performance. No significant changes in blood- or urine analyses and no side effects were seen.

Ginsenoside 20(S)-protopanaxadiol inhibits the proliferation and invasion of human fibrosarcoma HT1080 cells

Ginsenoside 20(S)-protopanaxadiol, one of metabolites of ginseng saponins, has been well characterized to possess the pleiotropic anticancer capabilities in several cancer cell lines. The object of this study was to investigate the effects of ginsenoside 20(S)-protopanaxadiol on the invasion in vitro and the expression of matrix metalloproteinase-2 in human fibrosarcoma HT1080 cells in absence of cytotoxicity. Our results showed that ginsenoside 20(S)-protopanaxadiol exerted a concentration-dependent inhibitory effect on the proliferation of HT1080 cells (IC50 was 76.78+/-2.24 microM, 48 hr). Treatment with 20(S)-protopanaxadiol significantly declined the invasive capacity of HT1080 cells compared to the control cells (P<0.01) in the in vitro invasion assay. Further analysis with gelatin zymography and western blotting revealed that both the activity and the expression of matrix metalloproteinase-2 decreased dramatically in a concentration-dependent manner (P<0.01). Taken together, these results indicated that ginsenoside 20(S)-protopanaxadiol is able to inhibit the invasiveness of HT1080 cells significantly in vitro and this action may be primarily due to down-regulating the expression of matrix metalloproteinase-2. Ginsenoside 20(S)-protopanaxadiol, a metabolite of ginseng, may be applied as a potential therapeutic agent in the prevention and treatment of cancer.

Reductions in levels of the Alzheimer's amyloid beta peptide after oral administration of ginsenosides

For millennia, ginseng and some of its components have been used to treat a wide variety of medical conditions, including age-related memory impairment. Because of its purported effects and apparently low rate of side effects, ginseng remains one of the top selling natural product remedies in the United States. Given its potential role for improving age-related memory impairments and its common use in China for the treatment of Alzheimer's disease-like symptoms, we analyzed the effects of commercially available preparations of ginseng on the accumulation of the Alzheimer's amyloid beta peptide (Abeta) in a cell-based model system. In this model system, ginseng treatment resulted in a significant reduction in the levels of Abeta in the conditioned medium. We next examined the effects of several compounds isolated from ginseng and found that certain ginsenosides lowered Abeta concentration in a dose-dependent manner with ginsenoside Rg3 having an approximate IC50 of under 25 microM against Abeta42. Furthermore, we found that three of these isolated components, ginsenoside Rg1, Rg3, and RE, resulted in significant reductions in the amount of Abeta detected in the brains of animals after single oral doses of these agents. The results indicate that ginseng itself, or purified ginsenosides, may have similarly useful effects in human disease.

Saponins composition in American ginseng leaf and berry assayed by high-performance liquid chromatography

The root of American ginseng is a commonly used herbal medicine in the United States. However, the compositions of American ginseng leaves and berries are not clear to date. In this study, we improved a method for the analysis of 12 ginsenosides based on solid phase extraction and high-performance liquid chromatography-ultraviolet. Good resolution was obtained for all tested ginsenosides: Rb1, Rb2, Rb3, Rc, Rd, Re, Rg1, Rg2, 20(R)-Rg2, Rg3, Rh1, and Rh2. Ginsenosides Rh1, Rg2, and 20(R)-Rg2 were easily separated with this column. The modified gradient elution program resulted in satisfactory linearity and precision. Solid phase extraction made the analysis accurate and efficient. Other investigators recently observed that ginsenoside Rb3 is a potent neuroprotective compound; it can promote learning and memory. In this report, we found that the major ginsenoside in American ginseng leaves and berries was ginsenoside Rb3, while Rb3 only had limited amounts in the root of American ginseng and other species of the Panax genus. Ginsenoside Rb3 was quantified as 4.71% in American ginseng leaves and 5.35% in berries, suggesting that American ginseng leaves and berries are new sources of ginsenoside Rb3.