Effect of ginseng saponins on exercise performance in non-trained rats

Nutrition Supplements to Stimulate Lipolysis: A Review in Relation to Endurance Exercise Capacity

Athletes make great efforts to increase their endurance capacity in many ways. Using nutrition supplements for stimulating lipolysis is one such strategy to improve endurance performance. These supplements contain certain ingredients that affect fat metabolism; furthermore, in combination with endurance training, they tend to have additive effects. A large body of scientific evidence shows that nutrition supplements increase fat metabolism; however, the usefulness of lipolytic supplements as ergogenic functional foods remains controversial. The present review will describe the effectiveness of lipolytic supplements in fat metabolism and as an ergogenic aid for increasing endurance exercise capacity. There are a number of lipolytic supplements available on the market, but this review focuses on natural ingredients such as caffeine, green tea extract, L-carnitine, Garcinia cambogia (hydroxycitric acid), capsaicin, ginseng, taurine, silk peptides and octacosanol, all of which have shown scientific evidence of enhancing fat metabolism associated with improving endurance performance. We excluded some other supplements owing to lack of data on fat metabolism or endurance capacity. Based on the data in this review, we suggest that a caffeine and green tea extract improves endurance performance and enhances fat oxidation. Regarding other supplements, the data on their practical implications needs to be gathered, especially for athletes.

[KOUJIN POWDER (RED GINSENG POWDER) WITH NINJIN-YOUEITO FOR FATIGUE DUE TO TARGETED THERAPY FOR ADVANCED RENAL CELL CARCINOMA: A RETROSPECTIVE COHORT STUDY]

(Purpose) Targeted therapy has been standard therapeutic approach for advanced renal cell carcinoma (RCC). General fatigue is frequently observed in patients who receive targeted therapies for advanced RCC. General fatigue makes it difficult to continue a standard schedule of treatment in many cases. In this preliminary report, we explored the effect of Koujin powder (red ginseng powder) with Ninjin-youeito for general fatigue induced by targeted therapies for advanced RCC. (Material and method) The patients who complained of general fatigue during the treatment of Tyrosine Kinase Inhibitors (TKIs) as targeted therapies for advanced RCC were included in this retrospective analysis. Thirty patients with advanced RCC were enrolled from January 2016 to December 2016 at Chiba University Hospital. Twelve patients were given 3 g of Koujin powder with 9 g of Ninjin-youeito orally for two to four weeks (ginseng combination group). Eighteen patients who were not orally administered were compared as a control group (ginseng non-combination group). General fatigue was assessed with the Cancer Fatigue Scale (CFS), which divides quality of fatigue into three subgroups by using a "physical subscale", an "affective subscale", and a "cognitive subscale". We compared CFS scores at baseline and 2-8 weeks after administration. (Results) There was no statistical difference in the clinical variables between the two groups. The total CFS score was significantly decreased after treatment in the ginseng combination group (average score, 21.8 points at baseline vs 18.5 points after treatment; p=0.041). On subgroup analyses, the physical subscale score was significantly reduced after treatment in the ginseng combination group (average score, 9.7 points at baseline vs 7 points after treatment; p=0.0042). In the ginseng non-combination group, the total CFS score was significantly increased during the course (average score, 16.2 points at baseline vs 20.6 points during the course; p=0.047). On subgroup analyses, the physical subscale score was significantly increased during the course (average score, 4.4 points at baseline vs 7.3 points during the course; p=0.0042). (Conclusions) Koujin powder with Ninjin-youeito can be a therapeutic approach for general fatigue induced by targeted therapies. The precise management for general fatigue can keep patients on therapy, consequently provides a survival benefit.

Metabonomic Profiling Reveals Cancer Chemopreventive Effects of American Ginseng on Colon Carcinogenesis in Apc(Min/+) Mice

American ginseng (Panax quinquefolius L.) is one of the most commonly used herbal medicines in the West. It has been reported to possess significant antitumor effects that inhibit the process of carcinogenesis. However, the mechanisms underlying its anticancer effects remain largely unresolved. In this study, we investigated the cancer chemopreventive effects of American ginseng on the progression of high fat (HF) diet-enhanced colorectal carcinogenesis with a genetically engineered Apc(Min/+) mouse model. The metabolic alterations in sera of experimental mice perturbed by HF diet intervention as well as the American ginseng treatment were measured by gas chromatography time-of-flight mass spectrometry (GC-TOFMS) and liquid chromatography time-of-flight mass spectrometry (LC-TOFMS) analysis. American ginseng treatment significantly extended the life span of the Apc(Min/+) mouse. Significant alterations of metabolites involving amino acids, organic acids, fatty acids, and carbohydrates were observed in Apc(Min/+) mouse in sera, which were attenuated by American ginseng treatment and concurrent with the histopathological improvement with significantly reduced tumor initiation, progression and gut inflammation. These metabolic changes suggest that the preventive effect of American ginseng is associated with attenuation of impaired amino acid, carbohydrates, and lipid metabolism. It also appears that American ginseng induced significant metabolic alterations independent of the Apc(Min/+) induced metabolic changes. The significantly altered metabolites induced by American ginseng intervention include arachidonic acid, linolelaidic acid, glutamate, docosahexaenoate, tryptophan, and fructose, all of which are associated with inflammation and oxidation. This suggests that American ginseng exerts the chemopreventive effects by anti-inflammatory and antioxidant mechanisms.

Improved inflammatory balance of human skeletal muscle during exercise after supplementations of the ginseng-based steroid Rg1

The purpose of the study was to determine the effect of ginseng-based steroid Rg1 on TNF-alpha and IL-10 gene expression in human skeletal muscle against exercise challenge, as well as on its ergogenic outcomes. Randomized double-blind placebo-controlled crossover trials were performed, separated by a 4-week washout. Healthy young men were randomized into two groups and received capsule containing either 5 mg of Rg1 or Placebo one night and one hour before exercise. Muscle biopsies were conducted at baseline, immediately and 3 h after a standardized 60-min cycle ergometer exercise. While treatment differences in glycogen depletion rate of biopsied quadriceps muscle during exercise did not reach statistical significance, Rg1 supplementations enhanced post-exercise glycogen replenishment and increased citrate synthase activity in the skeletal muscle 3 h after exercise, concurrent with improved meal tolerance during recovery (P<0.05). Rg1 suppressed the exercise-induced increases in thiobarbituric acids reactive substance (TBARS) and reversed the increased TNF-alpha and decreased IL-10 mRNA of quadriceps muscle against the exercise challenge. PGC-1 alpha and GLUT4 mRNAs of exercised muscle were not affected by Rg1. Maximal aerobic capacity (VO_2max) was not changed by Rg1. However, cycling time to exhaustion at 80% VO_2max increased significantly by ~20% (P<0.05). Conclusion: Our result suggests that Rg1 is an ergogenic component of ginseng, which can minimize unwanted lipid peroxidation of exercised human skeletal muscle, and attenuate pro-inflammatory shift under exercise challenge.

The pharmacology of actoprotectors: practical application for improvement of mental and physical performance

Actoprotectors are preparations that enhance body stability against physical loads without increasing oxygen consumption or heat production. Or, in short, actoprotectors are synthetic adaptogens with a significant capacity to improve physical performance. This paper explores the history of actoprotectors’development, their pharmacological properties, mechanism of action, and practical application to the improvement of mental and physical performance. A brief summary of the clinico-pharmacological characteristics of the main representatives of this class (bemitil and bromantane) is provided. Some other synthesized compounds, and even natural ones such as ginseng, also are regarded as potential actoprotectors, and these are treated herein as well. Actoprotectors, owing to their wide-ranging pharmacological activities, high efficiency and safety, can be applied under either normal or extreme conditions.

Wisconsin Ginseng (Panax quinquefolius) to improve cancer-related fatigue: a randomized, double-blind trial, N07C2

BACKGROUND

Safe, effective interventions to improve cancer-related fatigue (CRF) are needed because it remains a prevalent, distressing, and activity-limiting symptom. Based on pilot data, a phase III trial was developed to evaluate the efficacy of American ginseng on CRF.

METHODS

A multisite, double-blind trial randomized fatigued cancer survivors to 2000mg of American ginseng vs a placebo for 8 weeks. The primary endpoint was the general subscale of the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) at 4 weeks. Changes from baseline at 4 and 8 weeks were evaluated between arms by a two-sided, two-sample t test. Toxicities were evaluated by self-report and the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) provider grading.

RESULTS

Three hundred sixty-four participants were enrolled from 40 institutions. Changes from baseline in the general subscale of the MFSI-SF were 14.4 (standard deviation [SD] = 27.1) in the ginseng arm vs 8.2 (SD = 24.8) in the placebo arm at 4 weeks (P = .07). A statistically significant difference was seen at 8 weeks with a change score of 20 (SD = 27) for the ginseng group and 10.3 (SD = 26.1) for the placebo group (P = .003). Greater benefit was reported in patients receiving active cancer treatment vs those who had completed treatment. Toxicities per self-report and CTCAE grading did not differ statistically significantly between arms.

CONCLUSIONS

Data support the benefit of American ginseng, 2000mg daily, on CRF over an 8-week period. There were no discernible toxicities associated with the treatment. Studies to increase knowledge to guide the role of ginseng to improve CRF are needed.

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.

Supplementation with soybean peptides, taurine, Pueraria isoflavone, and ginseng saponin complex improves endurance exercise capacity in humans

The purpose of this study was to investigate the effects of a proprietary blend of soybean peptides, taurine, Pueraria isoflavone, and ginseng saponin complex (STPG capsule) on exercise performance in humans. Fourteen male volunteers were randomly assigned to two crossover treatments in which they consumed either four STPG capsules (STPG treatment) or placebo (P treatment) for 15 days before a 75% maximal oxygen uptake (VO(2max)) exhaustive cycling test. Blood samples and respiratory gas were collected prior to the exercise (Pre-Ex), at 10 (Ex-10), 15 (Ex-15), 20 (Ex-20), and 25 (Ex-25) minutes during exercise, and immediately after exercise (exhaustion) to assess the blood metabolites, cardiorespiratory responses, and energy substrate utilization. The result showed that exercise time to exhaustion of the 75% (VO(2max)) exhaustive cycling test of the STPG-treated subjects was significantly greater than with the P treatment (30.99 ± 2.01 vs. 28.05 ± 1.48 minutes). The plasma lactate concentrations at Ex-20 and Ex-25 in the STPG treatment were significantly lower with STPG treatment than with P treatment (10.5 ± 0.7 vs. 11.5 ± 0.8 and 10.7 ± 0.9 vs.12.3 ± 1.0 mmol/L, respectively). Nonesterified fatty acid levels at Ex-15, Ex-20, Ex-25, and exhaustion in the STPG group (0.27 ± 0.03, 0.32 ± 0.04, 0.32 ± 0.06, and 0.37 ± 0.05 mmol/L, respectively) were significantly higher than those in the P treatment (0.21 ± 0.03, 0.23 ± 0.03, 0.24 ± 0.03, and 0.25 ± 0.03 mmol/L, respectively). It was concluded that supplementation of four capsules (2 g) of STPG complex, consisting of soybean peptides, taurine, Pueraria isoflavone, and ginseng saponin, for 15 days was effective in promoting utilization of free fatty acids and improving exhaustive cycling test performance in humans.

Antidepressant-like effects of the active acidic polysaccharide portion of ginseng in mice

AIM OF THE STUDY

The biological of activity of Panax ginseng C.A. Meyer (ginseng) is complex but some of its known effects are related to affective and anxiety disorders, including the enhancement of neuroprotection, cellular resilience and plasticity. Whereas such effects suggest that ginseng might have antidepressant activity, previous studies show incongruent results. The sources of contrasting results might be many but one possibility is the utilization of different ginseng preparations in different studies. The current study was therefore designed to examine the effects of a very specific component of ginseng extract, the acidic polysaccharide portion of the plant (WGPA), containing arabinogalactan, type-I rhamnogalacturonan (RG-I)- and homogalacturonan (HG)-rich pectins.

MATERIALS AND METHODS

WGPA was extracted from ginseng roots and administered orally to mice at 100 mg/kg and 200 mg/kg doses. WGPA was administered chronically, once daily for 1 week before the start of experiments and throughout the behavioral tests battery. Mice were tested for spontaneous activity, social interactions, anxiety-like behavior in the elevated plus-maze (EPM) and despair-like behavior in the forced swim test (FST).

RESULTS

WGPA had no effects on spontaneous activity or behavior in the EPM. In contrast, 100 mg/kg (but not the 200 mg/kg) WGPA significantly reduced immobility time in the FST and both doses significantly increased social interactions and decreased aggressive behaviors in mice.

CONCLUSION

These results suggest that chronic WGPA treatment might have antidepressant-like effects that are unrelated to generalized behavioral changes. The results are discussed in the context of the known ability of the active ingredients of ginseng to increase neuroprotection, similar to many of the current antidepressant and mood stabilizing drugs.

Pilot study of Panax quinquefolius (American ginseng) to improve cancer-related fatigue: a randomized, double-blind, dose-finding evaluation: NCCTG trial N03CA

PURPOSE

This pilot trial sought to investigate whether any of three doses of American ginseng (Panax quinquefolius) might help cancer-related fatigue. A secondary aim was to evaluate toxicity.

METHODS

Eligible adults with cancer were randomized in a double-blind manner, to receive American ginseng in doses of 750, 1,000, or 2,000 mg/day or placebo given in twice daily dosing over 8 weeks. Outcome measures included the Brief Fatigue Inventory, vitality subscale of the Medical Outcome Scale Short Form-36 (SF-36), and the Global Impression of Benefit Scale at 4 and 8 weeks.

RESULTS

Two hundred ninety patients were accrued to this trial. Nonsignificant trends for all outcomes were seen in favor of the 1,000- and 2,000-mg/day doses of American ginseng. Area under the curve analysis of activity interference from the Brief Fatigue Inventory was 460-467 in the placebo group and 750 mg/day group versus 480-551 in the 1,000- and 2,000-mg/day arms, respectively. Change from baseline in the vitality subscale of the SF-36 was 7.3-7.8 in the placebo and the 750-mg/day arm, versus 10.5-14.6 in the 1,000- and 2,000-mg/day arms. Over twice as many patients on ginseng perceived a benefit and were satisfied with treatment over those on placebo. There were no significant differences in any measured toxicities between any of the arms.

CONCLUSION

There appears to be some activity and tolerable toxicity at 1,000-2,000 mg/day doses of American ginseng with regard to cancer-related fatigue. Thus, further study of American ginseng is warranted.

A randomized controlled crossover trial of the effect of ginseng consumption on the immune response to moderate exercise in healthy sedentary men

Ginseng is a popular herbal remedy that is reputed to increase resistance to stress and improve immune function. Regular exercise results in acute physiologic stress that affects the immune response. This study was conducted to investigate the effects of daily consumption of a standardized ginsenoside-containing North American ginseng (Panax quinquefolius) extract on immune function before, during, and after a moderate-exercise protocol in healthy sedentary men. Ten healthy males were randomized to receive either ginseng (1125 mg·d–1) or placebo for 35 days. After a 3 month washout period, subjects received the opposite treatment for another 35 days. An exercise test and blood collection were performed at the end of each treatment period. Immune parameters and blood hormone levels were measured before, during, and after the exercise stress protocol. Ginseng treatment reduced the peripheral blood concentration of CD8+ T cells and increased mitogen-stimulated T cell production of interleukin-2 ex vivo. Ginseng had no effect on total white blood cell counts; on concentrations of neutrophils, monocytes, or lymphocytes (CD3+, CD4+, CD16+, CD20+); on lymphocyte proliferation; or on neutrophil oxidative burst. Ginseng did not significantly affect exercise-induced changes in plasma concentrations of lactate, insulin, cortisol, or growth hormone. The consumption of ginseng for 5 weeks had a limited effect on the immune response to an acute exercise protocol.

Hot topics and landmark studies from the 43rd annual meeting of the American Society of Clinical Oncology

The results of several preclinical and clinical studies were reported by oncology professionals at the 43rd American Society of Clinical Oncology (ASCO) meeting, the largest international forum in which the latest achievements in cancer research are annually presented. The central theme this year was 'Translating Research into Practice', emphasizing the goal of forging stronger links between basic research and clinical practice. This review offers a critical, summarized selection of several of the foremost studies presented at the meeting. The focus is on the findings from randomized phase III trials that, in the authors' opinion, are most likely to have an immediate effect on clinical practice.

Ginseng on hyperglycemia: effects and mechanisms

It has been reported that American ginseng attenuates hyperglycemia and may present itself as a supplement to diabetes therapy. However, the lack of standardization in the usage of ginseng root leads to inconclusive results when applied to diabetes treatment. The mechanisms of American ginseng root in the treatment of diabetes remains a mystery. This greatly limits the effective utilization of American ginseng in facilitating diabetic therapy. Initiating studies have shown that American ginseng increases insulin production and reduces cell death in pancreatic β-cells. Also, studies have revealed American ginseng's ability to decrease blood glucose in type II diabetes patients as well as in streptozotocin-induced diabetic animals (STZ-diabetic mice). These data suggest that effects of ginseng in improving hyperglycemia may alter mitochondrial function as well as apoptosis cascades to ensure cell viability in pancreatic islet cells. This review briefly summarizes current knowledge of ginseng components and clinical studies related to diabetes. Further research will be needed to explore and identify the component(s) of ginseng, which may be responsible for the beneficial effects observed in animal studies which could then be extrapolated to human islets.

Neuroprotective effect of individual ginsenosides on astrocytes primary culture

Most of the known pharmacological effects of Panax ginseng on the central nervous system are due to its major components - ginsenosides. Although the antioxidant ability of ginseng root has already been established, this activity has never been evaluated for isolated ginsenosides on astrocytes. The activity of protopanaxadiols Rb(1), Rb(2), Rc and Rd, and protopanaxatriols Re and Rg(1) was evaluated in vitro on astrocytes primary culture by means of an oxidative stress model with H(2)O(2). The viability of astrocytes was determined by the MTT reduction assay and by the LDH release into the incubation medium. The effects on the antioxidant enzymes catalase, superoxide dismutase (SOD), glutathione peroxidases (GPx) and glutathione reductase (GR) and on the intracellular reactive oxygen species (ROS) formation were also investigated. Exposure of astrocytes to H(2)O(2) decreased cell viability as well as the antioxidant enzymes activity and increased ROS formation. Oxidative stress produced significant cell death that was reduced by previous treatment with the tested ginsenosides. Ginsenosides Rb(1), Rb(2), Re and Rg(1) were effective in reducing astrocytic death, while Rb(1), Rb(2), Rd, Re and Rg(1) decreased ROS formation, ginsenoside Re being the most active. Ginsenosides from P. ginseng induce neuroprotection mainly through activation of antioxidant enzymes.

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.

Evaluation ofBaccharis trimera andDavilla rugosa in tests for adaptogen activity

Baccharis trimera (Asteraceae) and Davilla rugosa (Dilleniaceae) are used popularly as tonics, aphrodisiacs and for stomach ailments, among other uses. Hydroalcohol extracts of the aerial parts of both plants were investigated with regard to their chemical constitution and their pharmacological activity in tests that evaluate adaptogen activity. Alkaloids, flavonoids, saponins, polyphenols/tannins and coumarins were identified in both extracts, while lignans were found only in the extract of Davilla rugosa. This extract presented also a marked antioxidant activity and exerted a moderate antiulcer effect in rats submitted to cold immobilization stress. It did not, however, inhibit the increase in the levels of ACTH and corticosterone induced by stress. Moreover, the Davilla rugosa did not improve the physical performance of mice submitted to forced exercise and the learning time of old rats in the T-maze, neither did it reduce the blood viscosity of the old animals. Conversely, the Baccharis trimera extract only presented a moderate antioxidant activity, without any positive effect on the other tests. These results point to the absence of an adaptogen activity of Baccharis trimera, with some effects that could be related to such an activity as regards the Davilla rugosa.

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

Ameliorating effects of red ginseng on learning and memory deficits due to hippocampal lesions and aging were reviewed; the performance of young rats with selective hippocampal lesions with or without red ginseng (p.o.), and aged rats with or without red ginseng (p.o.) in the spatial learning tasks was compared with that of sham-operated or intact young rats. Each rat was tested with 3 types of spatial learning tasks (distance movement task, DMT; random reward place search task, RRPST; and place learning task, PLT) in a circular open field using intracranial self-stimulation (ICSS) as reward. The results in the DMT and RRPST indicated that motivational and motor activity of young rats with hippocampal lesions with and without ginseng and aged rats with and without ginseng were not significantly different from that of control young rats. However, young rats with hippocampal lesions without ginseng and aged rats without ginseng displayed significant deficits in the PLT. Treatment with red ginseng significantly ameliorated place-navigation deficits in young rats with hippocampal lesions in the PLT. Similarly, red ginseng improved performance of aged rats in the PLT. The results, along with previous studies showing significant effects of red ginseng on the central nervous system, suggest that red ginseng ameliorates learning and memory deficits through effects on the central nervous system, partly through effects on the hippocampal formation. However, its mechanisms are still unclear, and further studies are required.

Ginseng administration protects skeletal muscle from oxidative stress induced by acute exercise in rats

Enzymatic activity was analyzed in the soleus, gastrocnemius (red and white) and plantaris muscles of acutely exercised rats after long-term administration of Panax ginseng extract in order to evaluate the protective role of ginseng against skeletal muscle oxidation. Ginseng extract (3, 10, 100, or 500 mg/kg) was administered orally for three months to male Wistar rats weighing 200 +/- 50 g before exercise and to non-exercised rats (N = 8/group). The results showed a membrane stabilizing capacity of the extract since mitochondrial function measured on the basis of citrate synthase and 3-hydroxyacyl-CoA dehydrogenase activities was reduced, on average, by 20% (P < 0.05) after exercise but the activities remained unchanged in animals treated with a ginseng dose of 100 mg/kg. Glutathione status did not show significant changes after exercise or treatment. Lipid peroxidation, measured on the basis of malondialdehyde levels, was significantly higher in all muscles after exercise, and again was reduced by about 74% (P < 0.05) by the use of ginseng extract. The administration of ginseng extract was able to protect muscle from exercise-induced oxidative stress irrespective of fiber type.

Ginseng: potential for the enhancement of cognitive performance and mood

Ginseng has been used medicinally in the Far East for several millennia and is currently one of the most widely taken herbal products throughout the world. It has been attributed with a plethora of physiological effects that could potentially benefit cognitive performance or mood. Studies involving animals show that ginseng and its constituent ginsenosides can modulate indices of stress, fatigue, and learning. However, there is a lack of adequately controlled research showing behavioural effects following chronic administration to humans. Recent research has demonstrated that single doses of ginseng most notably engender cognitive benefits in terms of improved memory, but can also be associated with 'costs' in terms of attention task deficits following less mnemonically beneficial doses. A single dose of ginseng has also been shown to modulate cerebroelectrical (EEG) activity. It is suggested that ginseng would benefit from rigorous research further delineating its acute effects and exploring the relationship between acute effects and those seen during and following chronic administration regimens.

Dose dependent changes in cognitive performance and mood following acute administration of Ginseng to healthy young volunteers

Recent evidence suggests that chronic administration of Ginseng can improve cognitive performance in animals and in humans. No previous study has examined the possibility of cognitive effects following single doses of Ginseng in healthy adults. The present study investigated whether acute administration of Ginseng (G115, Pharmaton SA) had any consistent effect on mood and four aspects of cognitive performance ("Quality of Memory", "Speed of Memory", "Quality of Attention" and "Speed of Attention") that can be derived by factor analysis of the Cognitive Drug Research computerised assessment battery. The study followed a placebo-controlled, double-blind, balanced, crossover design. Twenty healthy young adult volunteers received 200, 400, and 600 mg of G115, and a matching placebo, in counterbalanced order, with a 7 day wash-out period between treatments. Following a baseline cognitive assessment, further test sessions took place 1, 2.5, 4 and 6 h after the day's treatment. The most striking result was a significant improvement in "Quality of Memory" and the associated "Secondary Memory" factor at all time points following 400 mg of Ginseng. Both the 200 and 600 mg doses were associated with a significant decrement of the "Speed of Attention" factor at later testing times only. Subjective ratings of alertness were also reduced 6 h following the two lowest doses. To the best of our knowledge this represents the first demonstration of a modulation of mood and cognitive performance by acute administration of Ginseng.

Acute, dose-dependent cognitive effects of Ginkgo biloba, Panax ginseng and their combination in healthy young volunteers: differential interactions with cognitive demand

The present paper describes three studies examining the acute effects of single doses of Ginkgo biloba (GK501), Ginseng (G115) and their combination (Ginkoba M/E, Pharmaton SA) on the performance of healthy young adults (mean age 21 years) during serial arithmetic tasks with differing cognitive load. In each double-blind, placebo-controlled study three different treatment doses and a placebo were administered, according to a balanced crossover design, with a 7-day washout period between each dose. Participants' scores on two computerised serial subtraction tasks (Serial Threes and Serial Sevens) were assessed pre-dosing and at 1, 2.5, 4 and 6 h thereafter. A number of significant time, dose and task-specific effects were associated with each treatment. There was a dose-dependent improvement in speed of responding during Serial Threes following Ginkgo biloba. Different doses of Ginseng improved accuracy and slowed responses during Serial Sevens. The most striking result, however, was a highly significant and sustained increase in the number of Serial Sevens responses following 320 mg of the Ginkgo-Ginseng combination at all post-treatment testing times. This was accompanied by improved accuracy during Serial Sevens and Serial Threes following the 640 mg and the 960 mg dose, respectively. The paper concludes with speculation into the possible mechanisms underlying these effects.

Efficacy and safety of ginseng

Ginseng (Panax ginseng, C.A. Meyer) has been a popular herbal remedy used in eastern Asian cultures for thousands of years. In North America, the ginseng species indigenous to both Canada and the United States (Panax quinquefolium) represents an important industry for both domestic and export markets. There are numerous theories and claims describing the efficacy of ginseng, which can combat stress, enhance both the central and immune systems and contribute towards maintaining optimal oxidative status against certain chronic disease states and aging. Risk issues concerning the safety of ginseng at recommended dosages are less prominent and scientifically based. While some epidemiological or clinical studies have reported indications of efficacy for specific health benefits or potential toxicity, there are an equal number of studies that provide contradictory evidence. This situation has led to questionable conclusions concerning specific health benefits or risks associated with ginseng. Recent advances in the development of standardized extracts for both Panax ginseng (G-115) and Panax quinquefolius (CNT-2000) have and will continue to assist in the assessment of efficacy and safety standards for ginseng products. This paper reviews the scientific literature and evidence for ginseng efficacy and safety derived mostly from in vitro and animal studies and places emphasis on the need for more randomized, double-blinded, placebo clinical studies that can provide unequivocal conclusions. An example of the efficacy and safety of ginseng is provided with the description of biological activity of a North American ginseng extract (NAGE), which includes illustrating mechanisms for antioxidant activity without prooxidant properties.

Evaluation of the ergogenic properties of ginseng: an update

Ginseng has been used in the Orient for several thousand years as an 'adaptogenic' as well as a 'restorative' agent. It has been used to treat nervous disorders, anaemia, wakefulness, dyspnoea, forgetfulness and confusion, prolonged thirst, decreased libido, chronic fatigue, angina and nausea. Although the mechanisms underlying the alleged effects of ginseng remain to be elucidated, there is an extensive animal literature dealing with the effects of ginseng on the cardiovascular system, central nervous system, endocrine system, metabolism, and immune system. In our previous review dealing with the efficacy of ginseng, we concluded that while studies with animals show that ginseng, or its active components, may prolong survival to physical or chemical stress, there is generally a lack of controlled research demonstrating the ability of ginseng to improve or prolong performance in fatigued humans. In this review, we extend our earlier analysis on the potential efficacy of ginseng use in the enhancement of physical performance and modification of fatigue states. Our analysis reveals that published literature appearing since our earlier review has not resolved the equivocal nature of research evidence involving animals or humans. Also, the lack of unanimity in this research can be explained on the basis of various methodological problems such as inadequate sample size and lack of double-blind, control and placebo paradigms. In addition, the absence of acceptable approaches to the problem of 'sourcing', in concert with an absence of compliance data in human research, further complicates the interpretation of this research literature. Nevertheless, the use of ginseng continues to grow, and current sales are estimated to be over $US300 million annually. There is clearly a need for systematic research dealing with the efficacy of ginseng, and this research needs to take into account basic, fundamental design considerations if there is to be any hope of establishing whether or not ginseng possesses efficacy.