Electrocardiographic and hemodynamic effects of Panax ginseng

Therapeutic mechanisms of ginseng in coronary heart disease

Coronary heart disease (CHD) is the most common clinical manifestation of cardiovascular disease. It is characterized by myocardial ischemia, which is caused by coronary atherosclerosis. CHD is a significant global health problem with increasing prevalence every year because of significant changes in the lifestyles and diets. Ginseng is a traditional Chinese medicinal herb that has been used in food preparations and traditional medicine for several centuries. Several studies have demonstrated that ginseng improved cardiac function by normalizing blood glucose levels and decreasing blood pressure, oxidative stress, platelet aggregation, and lipid dysregulation in vivo. This review describes the current understanding of the mechanisms by which ginseng alleviates CHD, and provides a reference for the clinical development and application of ginseng as an alternative therapy for CHD.

A comprehensive quality analysis of randomized controlled clinical trials of Asian ginseng and American ginseng based on the CONSORT guideline

Ginseng is an international herb that has been used for thousands of years. Two species most commonly applied and investigated in the ginseng family are Asian ginseng and American ginseng. The number of randomized controlled clinical trials (RCTs) has conspicuously increased, driven by the rapid development of ginseng. However, the reporting of RCT items of ginseng is deficient because of different trial designs and reporting formats, which is a challenge for researchers who are looking for the data with high quality and reliability. Thus, this study focused on providing an extensive analysis of these two species and examined the quality of the RCTs, based on the Consolidated Standards of Reporting Trials (CONSORT) guideline. Ninety-one RCTs conducted from 1980 to 2019 that were related to Asian ginseng and American ginseng used singly met our inclusion criteria. We found that the reporting quality of the two species has improved during the past 40 years. Publication date and sample size were significantly associated with the reporting quality. Rigorous RCTs designed for the species of ginseng are warranted, which can shed light on product research and development of ginseng in the future.

Ginseng extract and ginsenosides improve neurological function and promote antioxidant effects in rats with spinal cord injury: A meta-analysis and systematic review

Spinal cord injury (SCI) is defined as damage to the spinal cord that temporarily or permanently changes its function. There is no definite treatment established for neurological complete injury patients. This study investigated the effect of ginseng extract and ginsenosides on neurological recovery and antioxidant efficacies in rat models following SCI and explore the appropriate dosage. Searches were done on PubMed, Embase, and Chinese databases, and animal studies matches the inclusion criteria were selected. Pair-wise meta-analysis and subgroup analysis were performed. Ten studies were included, and the overall methodological qualities were low quality. The result showed ginseng extract and ginsenosides significantly improve neurological function, through the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale (pooled MD = 4.40; 95% CI = 3.92 to 4.88; p < 0.00001), significantly decrease malondialdehyde (MDA) (n = 290; pooled MD = −2.19; 95% CI = −3.16 to −1.22; p < 0.0001) and increase superoxide dismutase (SOD) levels (n = 290; pooled MD = 2.14; 95% CI = 1.45 to 2.83; p < 0.00001). Both low (<25 mg/kg) and high dosage (≥25 mg/kg) showed significant improvement in the motor function recovery in SCI rats. Collectively, this review suggests ginseng extract and ginsenosides has a protective effect on SCI, with good safety and a clear mechanism of action and may be suitable for future clinical trials and applications.

Ginseng: A bibliometric analysis of 40-year journey of global clinical trials

BACKGROUND

Ginseng has a long history of widespread use and remarkable effects as traditional medicine, adjuvant and dietary supplement. The therapeutic value, diverse functionalities and rapid development of ginseng have driven a significant increase in the number of ginseng clinical trials, ranging from its use in various ailments, formulation to safety concerns. Despite the persistent interest in ginseng clinical research, the medical effectiveness of ginseng is inconclusive and there is a lack of bibliometric analysis of the hundreds of ginseng clinical trials.

AIM OF REVIEW

This review aims to provide an extensive overview of ginseng clinical trials over the past 40 years (1979-2018) in combination with a qualitative and quantitative analysis. The annual clinical trial analysis of time distribution, country and institution network analysis for space cooperation, statistical analysis for various functions, as well as efficiency and effect size were performed for global ginseng clinical trials. Besides, preparation categories, administration routes, and the safety of ginseng clinical trials were also investigated.

KEY SCIENTIFIC CONCEPTS OF REVIEW

The 40-year journey of ginseng clinical trials has experienced emerging, boom, and stable or transitional stages. The global network of ginseng clinical trials has relevant regional distribution in Asia, North America and Europe. South Korea makes a great contribution to building up large research clusters and strong cooperation links. Universities are the key contributors to ginseng clinical trials. The development of ginseng products could be focused on the clinical trial in diseases with higher effectiveness or effect size, such as sexual function and cognitive & behavior and require rigorous investigations and evidence to evaluate safety. More attention should be paid to different effects from different preparations. We believe this review will provide new insights into the understanding of global ginseng clinical trials and identifies potential future perspectives for research and development of ginseng.

Chemical components of ginseng, their biotransformation products and their potential as treatment of hypertension

Ginseng is an ancient perennial herb belonging to the family Araliaceae and genus Panax which has been used for medical therapeutics for thousands of years, particularly in China and other Asian cultures although increasing interest in ginseng has recently emerged in western societies. Ginseng is a complex substance containing dozens of bioactive and potentially effective therapeutic compounds. Among the most studied are the ginsenosides, which are triterpene saponins possessing a wide array of potential therapeutic effects for many conditions. The quantity and type of ginsenoside vary greatly depending on ginseng species and their relative quantity in a given ginseng species is greatly affected by extraction processes as well as by subjecting ginseng to various procedures such as heating. Adding to the complexity of ginsenosides is their ability to undergo biotransformation to bioactive metabolites such as compound K by enteric bacteria following ingestion. Many ginsenosides exert vasodilatating effects making them potential candidates for the treatment of hypertension. Their vascular effects are likely dependent on eNOS activation resulting in the increased production of NO. One proposed end-mechanism involves the activation of calcium-activated potassium channels in vascular smooth cells resulting in reduced calcium influx and a vasodilatating effect, although other mechanisms have been proposed as discussed in this review.

Herbal Medicine for Cardiovascular Diseases: Efficacy, Mechanisms, and Safety

Cardiovascular diseases (CVDs) are a significant health burden with an ever-increasing prevalence. They remain the leading causes of morbidity and mortality worldwide. The use of medicinal herbs continues to be an alternative treatment approach for several diseases including CVDs. Currently, there is an unprecedented drive for the use of herbal preparations in modern medicinal systems. This drive is powered by several aspects, prime among which are their cost-effective therapeutic promise compared to standard modern therapies and the general belief that they are safe. Nonetheless, the claimed safety of herbal preparations yet remains to be properly tested. Consequently, public awareness should be raised regarding medicinal herbs safety, toxicity, potentially life-threatening adverse effects, and possible herb–drug interactions. Over the years, laboratory data have shown that medicinal herbs may have therapeutic value in CVDs as they can interfere with several CVD risk factors. Accordingly, there have been many attempts to move studies on medicinal herbs from the bench to the bedside, in order to effectively employ herbs in CVD treatments. In this review, we introduce CVDs and their risk factors. Then we overview the use of herbs for disease treatment in general and CVDs in particular. Further, data on the ethnopharmacological therapeutic potentials and medicinal properties against CVDs of four widely used plants, namely Ginseng, Ginkgo biloba, Ganoderma lucidum, and Gynostemma pentaphyllum, are gathered and reviewed. In particular, the employment of these four plants in the context of CVDs, such as myocardial infarction, hypertension, peripheral vascular diseases, coronary heart disease, cardiomyopathies, and dyslipidemias has been reviewed, analyzed, and critically discussed. We also endeavor to document the recent studies aimed to dissect the cellular and molecular cardio-protective mechanisms of the four plants, using recently reported in vitro and in vivo studies. Finally, we reviewed and reported the results of the recent clinical trials that have been conducted using these four medicinal herbs with special emphasis on their efficacy, safety, and toxicity.

Excessive postextraction bleeding associated with Cordyceps sinensis: a case report and review of select traditional medicines used by Vietnamese people living in the United States

Many older people who have emigrated from Vietnam to the United States continue to use the traditional medicines that they used in their country of origin. Clinicians trained in the West may not be familiar with these products. We reviewed 6 Asian traditional medicines that are popular among older Vietnamese people living in the United States. Each medicine has significant side effects that can lead to complications in patients undergoing surgery. Here, we present the case of a patient who used Cordyceps sinensis daily as a tonic and experienced prolonged bleeding after dental surgery.

Randomized Controlled Trial of High-Volume Energy Drink Versus Caffeine Consumption on ECG and Hemodynamic Parameters

Background

Caffeine in doses <400 mg is typically not considered arrhythmogenic, but little is known about the additional ingredients in energy drinks. We evaluated the ECG and blood pressure (BP) effects of high‐volume energy drink consumption compared with caffeine alone.

Methods and Results

This was a randomized, double‐blind, controlled, crossover study in 18 young, healthy volunteers. Participants consumed either 946 mL (32 ounces) of energy drink or caffeinated control drink, both of which contained 320 mg of caffeine, separated by a 6‐day washout period. ECG, peripheral BP, and central BP measurements were obtained at baseline and 1, 2, 4, 6, and 24 hours post study drink consumption. The time‐matched, baseline‐adjusted changes were compared. The change in corrected QT interval from baseline in the energy drink arm was significantly higher than the caffeine arm at 2 hours (0.44±18.4 ms versus −10.4±14.8 ms, respectively; P=0.02). The QTc changes were not different at other time points. While both the energy drink and caffeine arms raised systolic BP in a similar fashion initially, the systolic BP was significantly higher at 6 hours when compared with the caffeine arm (4.72±4.67 mm Hg versus 0.83±6.09 mm Hg, respectively; P=0.01). Heart rate, diastolic BP, central systolic BP, and central diastolic BP showed no evidence of a difference between groups at any time point. Post energy drink, augmentation index was lower at 6 hours.

Conclusions

The corrected QT interval and systolic BP were significantly higher post high‐volume energy drink consumption when compared with caffeine alone. Larger clinical trials validating these findings and evaluation of noncaffeine ingredients within energy drinks are warranted.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02023723.

Electrocardiographic and Hemodynamic Effects of Coenzyme Q10 in Healthy Individuals: A Double-Blind, Randomized Controlled Trial

Background:

Coenzyme Q10 (C0Q10) is an endogenous cofactor required for mitochondrial energy production and touted to treat heart failure and prevent statin-induced myopathy. In guinea pig ventricular myocytes, C0Q10 prolongs action potential duration, an effect that might prolong the QTc interval in humans. Additionally, C0Q10 reduced blood pressure in patients with essential hypertension.

Objective:

To determine the electrocardiographic (ECG) and hemodynamic impact of C0Q10 in healthy individuals.

Methods:

Healthy volunteers (N = 26; 62% male, age 24 ± 3 y) were randomized to receive a single dose of C0Q10 50 mg and matching placebo in a crossover fashion with a 7 day washout period between treatments. Twelve-lead ECGs, systolic and diastolic blood pressure, and other hemodynamic parameters (cardiac index and systemic vascular resistance index) were evaluated immediately before (baseline) and 1, 3, 5, and 8 hours after ingestion of the study drug. ECG parameters (P wave and QRS complex duration; PR, QT, QTc, and RR intervals) were measured in lead II by one blinded investigator. For each time point, duplicate blood pressure levels were taken manually and then averaged. Hemodynamic parameters were measured using bioelectrical impedance cardiography.

Results:

C0Q10 had no effect on any of the evaluated ECG parameters. The maximum postdosing systolic blood pressure showed a statistically significant increase with C0Q10 (117 ± 10 vs 119 ± 10 mm Hg; p = 0.037), an effect driven by increases in cardiac index (3.09 vs 2.95 L/min/m2; p = 0.017). However, blood pressure elevation was most evident at the 5 hour timepoint (116 ± 10 vs 113 ± 11 mm Hg; p = 0.049) and was only transient. There were no differences between groups for maximum postdosing diastolic blood pressure.

Conclusions:

One dose of CoQ10 does not have any effect on ECG variables and exhibits only mild and transient effect on systolic blood pressure in young, healthy people.

Blood pressure-lowering effect of Korean red ginseng associated with decreased circulating Lp-PLA2 activity and lysophosphatidylcholines and increased dihydrobiopterin level in prehypertensive subjects

We evaluated the effects of red ginseng consumption on blood pressure (BP) and the fasting plasma metabolome. This randomized, double-blind, placebo-controlled study included nonobese, nondiabetic, prehypertensive subjects consuming 10 capsules daily containing 5 g red ginseng (n=31) or placebo (n=31). Fasting plasma metabolome profiles were obtained using ultra performance liquid chromatography-linear trap quadrupole Orbitrap MS. After 12 weeks, participants consuming red ginseng showed reductions of 6.5 and 5.0 mm Hg in systolic and diastolic BP, respectively. Compared with controls, those consuming red ginseng showed greater reductions in changed values of systolic BP, diastolic BP and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity, after adjusting for baseline values. In addition, the red ginseng group showed a greater increase in dihydrobiopterin levels and greater decrease in palmitic amide and lysophosphatidylcholines (lysoPCs). The change in diastolic BP positively correlated with changes in lysoPCs and Lp-PLA2 activity. The BP-lowering effect of red ginseng is associated with decreased Lp-PLA2 and lysoPCs and increased dihydrobiopterin levels in prehypertensive subjects (ClinicalTrials.gov: NCT02326766).

Electrocardiographic and blood pressure effects of energy drinks and Panax ginseng in healthy volunteers: A randomized clinical trial

BACKGROUND

Energy drink usage has been linked to emergency room visits and deaths. The objective of the study is to assess the electrocardiographic and blood pressure effects of energy drinks, Panax ginseng and placebo in healthy individuals.

METHODS

This was a randomized, double blinded, placebo controlled, crossover study. Young healthy volunteers with no comorbid conditions consumed 32oz of an energy drink, control drink with 800mg of Panax ginseng or matching placebo-control drink over 45min. Primary endpoints were QTc interval and systolic blood pressure. Secondary endpoints included QT interval, PR interval, QRS duration, heart rate, and diastolic blood pressure. All endpoints were assessed at baseline, 1, 2, 3.5, and 5.5h.

RESULTS

A significant increase in QTc interval 2h post energy drink consumption was evident when compared to placebo (3.37±10.7ms and -3.19±11.8ms respectively; p=0.030). Similarly, systolic blood pressure 2h post energy drink consumption increased when compared to placebo (2.00±6.37mmHg and -2.67±5.83mmHg respectively; p=0.014). The PR interval significantly reduced over a 2h period post energy drink use in a clinically non-meaningful manner. Heart rate at 2h was not significantly higher in the energy drink group when compared to others. The QT interval, QRS interval and diastolic blood pressure were not impacted at any time point.

CONCLUSIONS

Certain energy drinks consumed at a high volume significantly increase the QTc interval and systolic blood pressure by over 6ms and 4mmHg respectively. Panax ginseng does not have a significant impact on ECG or blood pressure parameters.

The effect of ginseng (genus Panax) on blood pressure: a systematic review and meta-analysis of randomized controlled clinical trials

Pre-clinical evidence indicates the potential for ginseng to reduce cardiovascular disease risk and acutely aid in blood pressure (BP) control. Clinical evidence evaluating repeated ginseng exposure, however, is controversial, triggering consumer and clinician concern. A systematic review and meta-analysis were conducted to assess whether ginseng has an effect on BP. MEDLINE, EMBASE, Cochrane and CINAHL were searched for relevant randomized controlled trials ⩾4 weeks that compared the effect of ginseng on systolic (SBP), diastolic (DBP) and/or mean arterial (MAP) BPs to control. Two independent reviewers extracted data and assessed methodological quality and risk of bias. Data were pooled using random-effects models and expressed as mean differences (MD) with 95% confidence intervals (CIs). Heterogeneity was assessed and quantified. Seventeen studies satisfied eligibility criteria (n=1381). No significant effect of ginseng on SBP, DBP and MAP was found. Stratified analysis, although not significant, appears to favour systolic BP improvement in diabetes, metabolic syndrome and obesity (MD=-2.76 mm Hg (95% CI=-6.40, 0.87); P=0.14). A priori subgroup analyses revealed significant association between body mass index and treatment differences (β=-0.95 mm Hg (95% CI=-1.56, -0.34); P=0.007). Ginseng appears to have neutral vascular affects; therefore, should not be discouraged for concern of increased BP. More high-quality, randomized, controlled trials assessing BP as a primary end point, and use of standardized ginseng root or extracts are warranted to limit evidence of heterogeneity in ginseng research and to better understand its cardiovascular health potential.

High-Dose Asian Ginseng (Panax Ginseng) for Cancer-Related Fatigue: A Preliminary Report

INTRODUCTION AND OBJECTIVE

Cancer-related fatigue (CRF) is the most common and severe symptom in patients with cancer. The number and efficacy of available treatments for CRF are limited. The objective of this preliminary study was to assess the safety of high-dose Panax ginseng (PG) for CRF.

METHODS

In this prospective, open-label study, 30 patients with CRF (≥4/10) received high-dose PG at 800 mg orally daily for 29 days. Frequency and type of side effects were determined by the National Cancer Institute's Common Terminology Criteria for Adverse Events, version 4.0. Scores on the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) scale, Edmonton Symptom Assessment System (ESAS), and Hospital Anxiety and Depression Scale (HADS) were assessed at baseline, day 15, and day 29. Global Symptom Evaluation (GSE) was assessed at day 29.

RESULTS

Of the 30 patients enrolled, 24 (80%) were evaluable. The median age was 58 years; 50% were females, and 84% were white. No severe (≥grade 3) adverse events related to the study drug were reported. Of the 24 evaluable patients, 21 (87%) had an improved (by ≥3 points) FACIT-F score by day 15. The mean ESAS score (standard deviation) for well-being improved from 4.67 (2.04) to 3.50 (2.34) (P = .01374), and mean score for appetite improved from 4.29 (2.79) to 2.96 (2.46) (P = .0097). GSE score of PG for fatigue was ≥3 in 15/24 patients (63%) with median improvement of 5.

CONCLUSION

PG is safe and improves CRF fatigue as well as overall quality of life, appetite, and sleep at night. Randomized controlled trials of PG for CRF are justified.

Modulation of endothelial function by Korean red ginseng (Panax ginseng C.A. Meyer) and its components in healthy individuals: a randomized controlled trial

AIMS

Ginseng root and its derivatives remain atop the most widely used medicinal herbs in cardiovascular disease, despite inadequate substantiation of efficacy. We previously reported the potential of Korean red ginseng (KRG) to affect vascular tone by decreasing arterial wave reflection via an unknown mechanism. Given the preclinical link between ginseng intake and vasoactivity related to nitric oxide (NO) production, we sought to directly evaluate the effects of KRG root and its major root components, on an established noninvasive measure of endothelial function.

METHODS

In an acute, randomized, placebo-controlled, double-blind, crossover design, 16 healthy participants (9M:7F, age:30 ± 9y, BMI: 24 kg ±3 kg/m(2) , systolicBP/diastolicBP: 109 ± 11/66 ± 8 mmHg) on four occasions were administered: KRG root (3 g), KRG ginsenosides extract, KRG polysaccharides extract, and cornstarch control. Extracted fractions were delivered at doses bioequivalent to those found in 3 g of KRG. Flow-mediated vasodilatation (FMD) assessment, preceding a brachial blood pressure measurement, was performed at baseline and at 90 and 180 min posttreatment to assess endothelial function.

RESULTS

KRG significantly improved FMD posttreatment. Maximal vasodilatation of Δ2.57 ± 2.8% occurred at 180 min compared with control (Δ-0.83 ± 2.7%, P = 0.003 for all comparisons). The ginsenoside extract produced a comparable response (Δ1.75 ± 2.6%), but not the polysaccharide fraction (Δ0.10 ± 2.7%). Brachial blood pressure remained unchanged for all treatments (P = 0.45).

CONCLUSIONS

KRG acutely improved endothelial function in healthy individuals, which appears to be attributable to its ginsenoside containing fraction. Our data confirm preclinical data and support the potential for these compounds as targets for therapeutic strategies in disorders involving endothelial dysfunction.

Review of cases of patient risk associated with ginseng abuse and misuse

Ginseng has long been used as a functional food or therapeutic supplement and it is empirically known to be safe and nontoxic. During recent decades, a number of in vitro and in vivo experiments, as well as human studies have been conducted to prove the safety of various types of ginseng samples and their components. Clinical trials, case reports, and in vitro and in vivo research articles addressing the safety, toxicity, and other adverse events of ginseng application were selected and reviewed. Patient risks associated with ginseng abuse and misuse such as affective disorder, allergy, cardiovascular and renal toxicity, genital organ bleeding, gynecomastia, hepatotoxicity, hypertension, reproductive toxicity, and anticoagulant-ginseng interaction were reviewed and summarized. There are some cases of patient risk associated with ginseng abuse and misuse depending on patients' conditions although further investigation in more cases is required to clarify these issues.

An evidence-based systematic review of bitter orange (Citrus aurantium) by the Natural Standard Research Collaboration

An evidence-based systematic review of bitter orange (Citrus aurantium) by the Natural Standard Research Collaboration consolidates the safety and efficacy data available in the scientific literature using a validated, reproducible grading rationale. This article includes written and statistical analysis of clinical trials, plus a compilation of expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Quality and risk of bias in Panax ginseng randomized controlled trials: a review

Panax ginseng is one of the most frequently used herbs in the world. Numerous trials have evaluated its clinical benefits. However, the quality of these studies has not been comprehensively and systematically assessed. We reviewed randomized controlled trials (RCTs) of Panax ginseng to evaluate their quality and risk of bias. We searched four English databases, without publication date restriction. Two reviewers extracted details about the studies' methodological quality, guided by the Consolidated Standards of Reporting Trials (CONSORT) checklist and its extension for herbal interventions. Risk of bias was determined using the Cochrane Risk of Bias tool. Of 475 potentially relevant studies, 58 met our inclusion criteria. In these 58 studies, 48.3% of the suggested CONSORT checklist items and 35.9% of the extended herbal items were reported. The quality of RCTs published after the CONSORT checklist improved. Until 1995 (before CONSORT) (n = 4), 32.8% of the items were reported in studies. From 1996-2006 (CONSORT published and revised) (n = 30), 46.1% were reported, and from 2007 (n = 24), 53.5% were reported (p = 0.005). After the CONSORT extension for herbal interventions was published in 2006, RCT quality also improved, although not significantly. Until 2005 (n = 34), 35.2% of the extended herbal items were reported in studies; and from 2006 onwards (n = 24), 37.3% were reported (p = 0.64). Most studies classified risk of bias as "unclear". Overall, the quality of Panax ginseng RCT methodology has improved since the CONSORT checklist was introduced. However, more can be done to improve the methodological quality of, and reporting in, RCTs.

What do most erectile dysfunction guidelines have in common? No evidence-based discussion or recommendation of heart-healthy lifestyle changes and/or Panax ginseng

Sexual health or erectile dysfunction (ED) state of the art guidelines provide a thorough overview of conventional prescription or other notable extrinsic treatment options. Yet, over the past 10-15 years, a plethora of international researchers have established that individual and comprehensive lifestyle changes can prevent and potentially improve ED. We review the lifestyle evidence that should equate to grade A or level 1 evidence recommendations for ED. We also review the evidence for Panax ginseng, an over-the-counter (OTC) dietary supplement with a 35-year history of laboratory investigations, multiple positive randomized trials over approximately 15 years and several independent meta-analyses and systematic reviews. Perhaps it is time to at least discuss and even emphasize lifestyle and other non-conventional interventions in ED guidelines so that patients can explore a diversity of potentially synergistic choices with their physicians and can improve their quality and quantity of life. Ignoring the consistent, positive data on lifestyle modifications in ED guidelines, for example, is tantamount to ignoring diet and lifestyle changes to reduce the risk of or ameliorate cardiovascular diseases.

Panax ginseng in randomised controlled trials: a systematic review

Panax ginseng C.A. Meyer is a common herb with many purported health benefits. However, there is no conclusive evidence supporting its use in the treatment of any particular disease. We conducted a systematic review to evaluate randomised controlled trials. Four English databases were searched with no publication date restriction. Included studies evaluated P. ginseng in patients with any type of disease or in healthy individuals. We assessed the quality of studies using the Cochrane risk of bias tool. Of the 475 potentially relevant studies, 65 met the inclusion criteria. These studies examined P. ginseng's effects on psychomotor performance (17 studies), physical performance (ten), circulatory system (eight), glucose metabolism (six), the respiratory system (five), erectile dysfunction (four), immunomodulation (four), quality of life/mood (four), antioxidant function (two), cancer (two), menopausal symptoms (two) and dry mouth (one). The risk of bias was unclear in most studies. Authors evaluated adverse events in 40 studies, with 135 minor events and no serious adverse events reported. P. ginseng shows promising results for improving glucose metabolism and moderating the immune response. This may have implications for several diseases including type 2 diabetes and chronic respiratory conditions. Further studies are needed to explore P. ginseng's potential as an effective treatment for these and other health conditions.

Effects of Korean Red Ginseng on Cardiovascular Risks in Subjects with Metabolic Syndrome: a Double-blind Randomized Controlled Study

Background

This study investigated the effects of Korean red ginseng (KRG) supplementation on metabolic parameters, inflammatory markers, and arterial stiffness in subjects with metabolic syndrome.

Methods

We performed a randomized, double-blind, placebo-controlled, single-center study in 60 subjects who were not taking drugs that could affect metabolic and vascular functions. Subjects were randomized into either a KRG (4.5 g/d) group or a placebo group for a 12-week study. We collected anthropometric measurements, blood for laboratory testing, and brachial-ankle pulse wave velocity (baPWV) at the initial (week 0) and final (week 12) visits.

Results

A total of 48 subjects successfully completed the study protocol. Oral administration of KRG did not significantly affect blood pressure, oxidative or inflammatory markers, or baPWV.

Conclusion

We found no evidence that KRG had an effect on blood pressure, lipid profile, oxidized low density lipoprotein, fasting blood glucose, or arterial stiffness in subjects with metabolic syndrome. These findings warrant subsequent longer-term prospective clinical investigations with a larger population.

Trial Registration

ClinicalTrials.gov Identifier: NCT00976274

Korean red ginseng improves blood pressure stability in patients with intradialytic hypotension

Introduction. Intradialytic hypotension (IDH) is a common complication during hemodialysis which may increase mortality risks. Low dose of Korean red ginseng (KRG) has been reported to increase blood pressure. Whether KRG can improve hemodynamic stability during hemodialysis has not been examined. Methods. The 8-week study consisted of two phases: observation phase and active treatment phase. According to prehemodialysis blood pressure (BP), 38 patients with IDH were divided into group A (BP ≥ 140/90 mmHg, n = 18) and group B (BP < 140/90 mmHg, n = 20). Patients were instructed to chew 3.5 gm KRG slices at each hemodialysis session during the 4-week treatment phase. Blood pressure changes, number of sessions disturbed by symptomatic IDH, plasma levels of vasoconstrictors, blood biochemistry, and adverse effects were recorded. Results. KRG significantly reduced the degree of blood pressure drop during hemodialysis (P < 0.05) and the frequency of symptomatic IDH (P < 0.05). More activation of vasoconstrictors (endothelin-1 and angiotensin II) during hemodialysis was found. The postdialytic levels of endothelin-1 and angiotensin II increased significantly (P < 0.01). Conclusion. Chewing KRG renders IDH patients better resistance to acute BP reduction during hemodialysis via activation of vasoconstrictors. Our results suggest that KRG could be an adjuvant treatment for IDH.

Therapeutic potential of ginseng in the management of cardiovascular disorders

Although employed in Asian societies for thousands of years, the use of ginseng as an herbal medication for a variety of disorders has increased tremendously worldwide in recent years. Ginseng belongs to the genus Panax, of which there exists a variety, generally reflecting their geographic origin. North American ginseng (Panax quinquefolius) and Asian ginseng (Panax ginseng) are two such varieties possessing a plethora of pharmacological properties, which are attributed primarily to the presence of different ginsenosides that bestow these ginsengs with distinct pharmacodynamic profiles. The many cardiovascular benefits attributed to ginseng include cardioprotection, antihypertensive effects, and attenuation of myocardial hypertrophy and heart failure. Experimental studies have revealed a number of beneficial properties of ginseng, particularly in the area of cardiac protection, where ginseng and ginsenosides have been shown to protect the ischaemic and reperfused heart in a variety of experimental models. Emerging evidence also suggests that ginseng attenuates myocardial hypertrophy, thus blunting the remodelling and heart failure processes. However, clinical evidence of efficacy is not convincing, likely owing primarily to the paucity of well designed, randomized, controlled clinical trials. Adding to the complexity in understanding the cardiovascular effects of ginseng is the fact that each of the different ginseng varieties possesses distinct cardiovascular properties, as a result of their respective ginsenoside composition, rendering it difficult to assign a general, common cardiovascular effect to ginseng. Additional challenges include the identification of mechanisms (likely multifaceted) that account for the effects of ginseng and determining which ginsenoside(s) mediate these cardiovascular properties. These concerns notwithstanding, the potential cardiovascular benefit of ginseng is worthy of further studies in view of its possible development as a cardiovascular therapeutic agent, particularly as adjunctive therapy to existing medications.

Systematic review of randomized controlled trials evaluating the efficacy and safety of ginseng

This systematic review aims to evaluate the available evidence from randomized clinical trials of the clinical efficacy and safety of ginseng. Systematic literature searches were performed in 13 databases up to March 2009 without language restriction. All randomized clinical trials evaluating the clinical effects or safety of the use of ginseng monopreparations (Panax ginseng or P. quinquefolium) were considered for inclusion. A total of 411 potentially relevant studies were identified and 57 randomized clinical trials were included. The main indications included glucose metabolism, physical performance, psychomotor function, sexual function, cardiac function, pulmonary disease, and cerebrovascular disease. We found strong evidence of a positive effect of ginseng on glucose metabolism, psychomotor function, and pulmonary disease, whereas evidence suggests that ginseng is not effective at enhancing physical performance. However, ginseng generally has a good safety profile and the incidence of adverse effects seems to be low. In conclusion, our review compiles the evidence on the use of ginseng, finding a strong positive potential for glucose metabolism, psychomotor function, and pulmonary disease, but not for physical performance enhancement.

Amelioration of radiation-induced hematological and biochemical alterations in Swiss albino mice by Panax ginseng extract

BACKGROUND

This study was carried out to observe the radioprotective effect of Panax ginseng root extract (PGE) against radiation-induced hematological and biochemical alterations in blood and liver of mice. Materials and methods. Adult Swiss albino mice were exposed to 6 Gy gamma radiation in the presence (experimental) or absence (control) of PGE to study the quantitative and qualitative alterations in the blood and liver.

RESULTS

Radiation exposure resulted in a significant decline (P<.001) in erythrocyte count, hemoglobin (Hb), and hematocrit (Hct) in peripheral blood. Maximum changes in all the parameters were observed on day 3 after irradiation. In contrast, PGE-pretreated irradiated animals showed a significant increase in erythrocyte, Hct, and Hb values compared with irradiated controls. Furthermore, a significant elevation in lipid peroxidation level over normal was recorded in irradiated control mice, whereas this increase was considerably lesser in PGE pretreated animals. Likewise, pretreatment with PGE caused a significant increase in glutathione levels in serum as well as in liver in comparison to irradiated controls.

CONCLUSION

From this study, it is clearly evident that PGE provides protection against radiation-induced hematological and biochemical alterations in Swiss albino mice.

Effects of Korean red ginseng (Panax ginseng C.A. Mayer) and its isolated ginsenosides and polysaccharides on arterial stiffness in healthy individuals

BACKGROUND

Preclinical studies indicate a role of Korean red ginseng (KRG) in the modulation of vascular function; however, clinical evidence is scarce. Therefore, the objective of this study was to investigate the effect of KRG root on peripheral blood pressure (BP) and augmentation index (AI), an emerging method to assess cardiovascular risk beyond conventional BP measurements. Furthermore, in an attempt to elucidate which of the major components of KRG is responsible for these effects, the ginsenoside and polysaccharide fractions isolated from the same KRG root were also investigated.

METHODS

The study was designed as an acute randomized, controlled, double blind, crossover trial. A total of 17 healthy fasted individuals (gender: 9 males:8 females, age: 30 +/- 9 years, body mass index: 25 +/- 3 kg/m(2), systolic BP (SBP): 110 +/- 10.1, diastolic BP (DBP): 65 +/- 7 mm Hg) received, on separate occasions, four treatments consisting of: 3 g of either placebo, KRG root, or a KRG root bioequivalent dose of ginsenoside or polysaccharide fractions. BP and AI were measured by applanation tonometry at baseline, 1, 2, and 3 h post-treatment.

RESULTS

Compared to placebo, 3 g of KRG significantly lowered radial AI by 4.6% (P = 0.045), whereas the ginsenoside fraction comparably decreased AI by 4.8% (P = 0.057), and no effect was observed with the polysaccharides. There were no differences in BP between treatments.

CONCLUSION

Although preliminary, this study is the first to demonstrate that KRG may improve arterial stiffness as measured by AI. In addition, it appears that ginsenosides may be the principal pharmacologically active component of the root, rather than the polysaccharide fraction. This study supports the results seen with KRG in the preclinical studies and warrants further investigation on acute and long-term endothelial parameters.

Ginseng compounds: an update on their molecular mechanisms and medical applications

Ginseng is one of the most widely used herbal medicines and is reported to have a wide range of therapeutic and pharmacological applications. Ginsenosides, the major pharmacologically active ingredients of ginseng, appear to be responsible for most of the activities of ginseng including vasorelaxation, antioxidation, anti-inflammation and anti-cancer. Approximately 40 ginsenoside compounds have been identified. Researchers now focus on using purified individual ginsenoside to reveal the specific mechanism of functions of ginseng instead of using whole ginseng root extracts. Individual ginsenosides may have different effects in pharmacology and mechanisms due to their different chemical structures. Among them the most commonly studied ginsenosides are Rb1, Rg1, Rg3, Re, Rd and Rh1. The molecular mechanisms and medical applications of ginsenosides have attracted much attention and hundreds of papers have been published in the last few years. The general purpose of this update is to provide information of recently described effects of ginsenosides on antioxidation, vascular system, signal transduction pathways and interaction with receptors. Their therapeutic applications in animal models and humans as well as the pharmacokinetics and toxicity of ginsenosides are also discussed in this review. This review concludes with some thoughts for future directions in the further development of ginseng compounds as effective therapeutic agents.

Ginseng compounds: an update on their molecular mechanisms and medical applications

Ginseng is one of the most widely used herbal medicines and is reported to have a wide range of therapeutic and pharmacological applications. Ginsenosides, the major pharmacologically active ingredients of ginseng, appear to be responsible for most of the activities of ginseng including vasorelaxation, antioxidation, anti-inflammation and anti-cancer. Approximately 40 ginsenoside compounds have been identified. Researchers now focus on using purified individual ginsenoside to reveal the specific mechanism of functions of ginseng instead of using whole ginseng root extracts. Individual ginsenosides may have different effects in pharmacology and mechanisms due to their different chemical structures. Among them the most commonly studied ginsenosides are Rb1, Rg1, Rg3, Re, Rd and Rh1. The molecular mechanisms and medical applications of ginsenosides have attracted much attention and hundreds of papers have been published in the last few years. The general purpose of this update is to provide information of recently described effects of ginsenosides on antioxidation, vascular system, signal transduction pathways and interaction with receptors. Their therapeutic applications in animal models and humans as well as the pharmacokinetics and toxicity of ginsenosides are also discussed in this review. This review concludes with some thoughts for future directions in the further development of ginseng compounds as effective therapeutic agents.

Study designs of randomized controlled trials not based on Chinese medicine theory are improper

Current biomedical research methods to evaluate the efficacy of Chinese medicine interventions are often conceptually incompatible with the theory and clinical practice of Chinese medicine. In this commentary, we (1) highlight the theory and principles underlying Chinese medicine clinical practice; (2) use ginseng as an example to describe clinical indications in Chinese medicine; (3) propose a framework guided by Chinese medicine theory for the evaluation of study designs in Chinese medicine research; and (4) evaluate 19 randomized, double-blind, placebo-controlled trials of ginseng. Our analysis indicates that all 19 trials with both positive and negative results confirm the specific effects of ginseng indicated by Chinese medicine theory. Study designs guided by Chinese medicine theory are necessary to validate and improve future randomized controlled clinical trials in Chinese medicine.

Protective effects of ginsenoside Rb1 on human umbilical vein endothelial cells in vitro

Ginseng has beneficial effects on the cardiovascular system, but its underlying mechanism is unclear. This study investigated the effects of ginsenoside Rb1, a major constituent of ginseng, on the changes of lactate dehydrogenase (LDH) activity, nitric oxide (NO), tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor-1 (PAI-1) in oxidized low-density lipoprotein (oxLDL)-injuring endothelial cells. Human umbilical vein endothelial cells were cultured and divided into 6 groups (n = 6): control group, oxLDL alone group (100 mg/L), ginsenoside Rb1 alone group (10 microg/mL), oxLDL plus ginsenoside Rb1 groups (0.1, 1.0, and 10 microg/mL, respectively.). Twenty-four hours after treatment, LDH activity and concentrations of NO, t-PA, and PAI-1 in culture medium were measured while the expressions of endothelial nitric oxide synthase (eNOS), t-PA, and PAI-1 mRNA in endothelial cells were detected by reverse-transcriptase polymerase chain reaction. Compared with control group, oxLDL (100 mg/L) caused LDH activity, the expressions of eNOS and t-PA mRNA, and concentrations of NO and t-PA to significantly decrease (P < 0.05, respectively), and it also led to dramatic increase of PAI-1 mRNA and concentration (P < 0.05, respectively). Ginsenoside Rb1 alone did not demonstrate this ability. High-dose Rb1 (10 microg/mL) could block the effects of oxLDL on LDH activity, mRNA of eNOS, t-PA, and PAI-1, and concentrations of NO, t-PA, and PAI-1 (P < 0.05, respectively), and neither low-dose Rb1 (0.1 microg/mL) nor medium-dose Rb1 (1.0 microg/mL) demonstrated this ability. We conclude that ginsenoside Rb1 has protective effects on oxLDL-injuring human vascular endothelial cells and can reverse the effects of oxLDL on NO, t-PA, and PAI-1.

Effects of echinacea on electrocardiographic and blood pressure measurements

PURPOSE

The effects of Echinacea purpurea on electrocardiographic and blood pressure measurements in healthy volunteers were evaluated.

METHODS

Healthy volunteers were randomized to receive a single 350-mg dose of E. purpurea or placebo in a crossover fashion with a seven-day washout period between treatment phases. Twelve-lead electrocardiograms were acquired, and systolic and diastolic blood pressure measurements were taken immediately before (baseline) and at one, three, five, and eight hours after ingestion of the study drug. Electrocardiographic variables (P wave and QRS complex duration and PR, Q-T, Q-Tc, and RR intervals) were measured in lead II by one blinded study investigator. Duplicate blood pressure determinations were taken manually at each time point and then averaged. The maximum posttreatment values, irrespective of time point, for each electrocardiographic and blood pressure measurement were compared between groups.

RESULTS

Of the 17 healthy adults initially screened for this study, 16 completed both phases. There was no difference in maximum posttreatment electrocardiographic or blood pressure (systolic or diastolic) variables noted between groups. Mild headache was reported by one patient receiving echinacea and one receiving placebo. One participant receiving echinacea experienced shortness of breath five hours posttreatment and mild flu-like symptoms after eight hours; symptoms completely resolved over the next several days.

CONCLUSION

A single 350-mg dose of E. purpurea had no effect on electrocardiographic and blood pressure measurements of healthy volunteers.

Long-term intake of North American ginseng has no effect on 24-hour blood pressure and renal function

Ginseng is consumed by 10% to 20% of adults in Asia and by up to 5% in Western countries. Despite observational evidence suggesting a link between its intake and the development of hypertension, there remains no long-term scrutiny for its effect on blood pressure (BP). We therefore undertook a randomized, placebo-controlled, double-blinded, crossover trial in 52 hypertensive individuals to determine the effect of 12-week North American ginseng intake on 24-hour BP; we also measured serum cystatin C as a marker of renal function. After a 4-week placebo run-in, we randomly assigned 52 participants to 3 g/day of ginseng or placebo for 12 weeks. This was followed by an 8-week washout and a subsequent 12-week period in which the opposite treatment was administered. At run-in and at weeks 0 and 12 of each treatment period, participants were fitted with an ambulatory BP monitor to assess 24-hour BP. The primary outcome was the treatment difference at week 12 in mean 24-hour systolic BP. Secondary outcomes were treatment differences at week 12 in other ambulatory BP parameters and serum cystatin C. Forty participants (77%) completed the trial, with 3 removed from main analysis (n=2, antihypertensive drug changes; n=1, incomplete ambulatory monitoring). In the remaining 37, 12-week ginseng treatment was associated with a neutral effect on all ambulatory BP parameters compared with placebo; an intention-to-treat analysis supported this. Ginseng did not affect serum cystatin C level. Overall, long-term ginseng use had no effect on 24-hour BP and renal function in hypertensive individuals.

Systematic review of the effects of ginseng on cardiovascular risk factors

OBJECTIVE

To examine the evidence for the efficacy of ginseng (Panax spp.) on cardiovascular risk factors, including blood pressure, lipid profiles, and blood glucose, and to summarize reported cardiovascular adverse events.

DATA SOURCES

We searched MEDLINE, AMED, BIOSIS, CAB, EMBASE, and the Cochrane Controlled Trials databases through July 2005 and performed hand searches of bibliographies.

STUDY SELECTION AND DATA EXTRACTION

Short- or long-term, randomized, controlled trials and nonrandomized studies published in English were included. Data were extracted in a standardized manner, and 2 independent investigators assessed methodologic quality of the studies. Thirty-four studies were identified with results for blood pressure, lipids, and/or blood glucose. Due to heterogeneity of the studies, we were unable to perform a meta-analysis. Data on cardiovascular adverse events were extracted from events reported in identified studies and from case reports.

DATA SYNTHESIS

The majority of studies were short term. Ginseng may slightly decrease blood pressure compared with placebo (range 0-4%). We found mixed results for an effect on lipids, with 5 of 9 studies showing improvement in one or more lipid parameters compared with baseline (range 7-44%). We identified several studies showing that ginseng lowers blood glucose, but overall studies were inconsistent.

CONCLUSIONS

Current evidence does not support the use of ginseng to treat cardiovascular risk factors. Some studies suggest a small reduction in blood pressure. Despite some evidence showing that ginseng lowers blood glucose and improves lipid profiles, well-designed, randomized, controlled trials evaluating its effects are lacking.

Absence of QTc-Interval-Prolonging or Hemodynamic Effects of a Single Dose of Bitter-Orange Extract in Healthy Subjects

STUDY OBJECTIVE

To evaluate the hemodynamic and electrocardiographic effects of a single dose of commercially available bitter-orange dried-fruit extract, which is increasingly being used in dietary supplements.

DESIGN

Randomized, double-blind, placebo-controlled, crossover study.

SETTING

University of Connecticut, Storrs Campus.

SUBJECTS

Eighteen healthy volunteers aged 18 years or older.

INTERVENTION

Subjects were given either placebo or bitter-orange dried-fruit extract (450 mg standardized to 27 mg of m- or p-synephrine) in phase 1. The opposite treatment was given during phase 2 after a washout period of at least 7 days.

MEASUREMENTS AND MAIN RESULTS

The rate-corrected QT (QTc) interval and blood pressure were measured before dosing and at 1, 3, 5, and 8 hours after dosing. Mean+/-SD values of the maximum postdose values were compared between groups. Subjects receiving bitter-orange extract versus those receiving placebo had similar postdose QTc intervals (402+/-29 vs 403+/-24 msec, p=0.653), systolic blood pressure (114+/-10 vs 115+/-8 mm Hg, p=0.686) and diastolic blood pressure (68+/-9 vs 68+/-8, p=0.879).

CONCLUSION

Bitter-orange dried-fruit extract standardized to m- or p-synephrine 27 mg did not significantly alter the QTc interval or blood pressure after a single dose was administered. Future studies are necessary to ensure the safety of this herbal product with multiple doses.

Hemodynamic impact of an ephedra-free multicomponent weight-loss supplement

PURPOSE

The effect of Metabolife Ephedra-Free on blood pressure (BP) and hemodynamics was studied.

METHODS

Healthy volunteers were randomly assigned to take a single dose of Metabolife Ephedra-Free or matching placebo and then crossed over to the opposite treatment after a seven-day washout period. BP was measured at baseline and one, three, and five hours after administration. Cardiac index, systemic vascular resistance index (SVRI), and total thoracic fluid content were determined in a subgroup of subjects.

RESULTS

Twenty patients (mean +/- S.D. age, 24.8 +/- 1.9 years) completed the study. No significant differences in systolic or diastolic BP were found between the Metabolife Ephedra-Free and placebo groups. In the subgroup (n = 8), SVRI was higher (but not significantly so) in the Metabolife Ephedra-Free group than in the placebo group at one hour (2162.5 +/- 421.1 versus 1934.6 +/- 344.2 dyn x sec x cm(-5) x m(2)); the difference was significant at five hours (1981.6 +/- 293.3 versus 1765.1 +/- 340.3 dyn x sec x cm(-5) x m(2)).

CONCLUSION

Single doses of Metabolife Ephedra-Free did not affect BP in healthy young volunteers. SVRI did not exceed the normal range but was elevated at five hours compared with SVRI in placebo recipients.

Herbs and alternative therapies: Relevance to hypertension and cardiovascular diseases

Herbal remedies, supplements, and alternative therapeutic items are used by many patients with hypertension and cardiovascular diseases. Scientific knowledge about their efficacy and safety is lacking, and unfortunately, physicians are frequently not aware that patients are using these nontraditional forms of medical care. Patients may anticipate physicians' disapproval of their use, or not realize that it is important for the physician to know what they are taking. Therefore, it is imperative that patients are asked nonjudgmental questions about current and past use of herbals and alternative therapies. Even when physicians are aware of such use, they feel poorly trained to identify the constituents and effects. Although many such therapies are innocuous, several herbal or alternative therapeutic items can significantly elevate blood pressure or cause interactions with cardiovascular drugs. Practitioners in cardiovascular medicine should be competent and know current scientific evidence for the benefits and adverse effects of herbal supplements and provide patients reasonable advice. In this brief article, we review the epidemiology of alternative therapy use, and select several important herbal or other supplements that patients with hypertension and cardiovascular diseases may be taking. We discuss the therapies considered biological in nature as opposed to mind-body interventions or manipulative body or energy therapies.

North American ginseng exerts a neutral effect on blood pressure in individuals with hypertension

An early observational study suggested that ginseng could elevate blood pressure. This caused concern because 4.5% of American adults use ginseng, with a popular choice being North American ginseng. To date, North American ginseng lacks hemodynamic evaluation; therefore, we conducted a randomized, double-blinded, controlled trial to investigate its effect on blood pressure in 16 hypertensive individuals (mean+/-SD age 61.1+/-8.1 years; systolic/diastolic blood pressure 132.4+/-12.8/83.3+/-8.1 mm Hg; 13 on antihypertensives). We used 6 batches of North American ginseng root that varied in quality and ginsenoside content, representing the spectrum of this ginseng on the market. On 8 mornings, each participant was fitted with an ambulatory blood pressure monitor, which measured blood pressure during a 30-minute baseline period. Each participant then consumed in a randomized and double-blind fashion 3 g of encapsulated treatment: placebo (on 2 mornings) or powdered North American ginseng (on 6 mornings). After treatment, blood pressure was measured every 10 minutes for 160 minutes, and its change at each post-treatment time point relative to baseline was determined per individual and averaged, and the mean was obtained for the overall 160-minute period. None of the North American ginsengs or their mean differed from placebo in their effect on overall (160 minutes) mean blood pressure change. None affected blood pressure versus placebo at the 10-minute intervals; but their mean versus placebo increased systolic and diastolic blood pressure at 140 and 160 minutes, respectively, and lowered diastolic blood pressure at 100 minutes. The findings together suggested that North American ginseng exerts a neutral acute effect on blood pressure in hypertensive individuals.

Radioprotective potential of ginseng

A majority of potential radioprotective synthetic compounds have demonstrated limited clinical application owing to their inherent toxicity, and thus, the seeking of naturally occurring herbal products, such as ginseng, for their radioprotective capability has become an attractive alternative. In general, ginseng refers to the roots of the species of the genus Panax. As a medicinal herb, ginseng has been widely used in traditional Chinese medicine for its wide spectrum of medicinal effects, such as tonic, immunomodulatory, antimutagenic, adaptogenic and antiaging activities. Many of its medicinal effects are attributed to the triterpene glycosides known as ginsenosides (saponins). This review addresses the issue of the radioprotective effects of ginseng on mammalian cells both in vitro and in vivo. Results indicate that the water-soluble extract of whole ginseng appears to give a better protection against radiation-induced DNA damage than does the isolated ginsenoside fractions. Since free radicals play an important role in radiation-induced damage, the underlying radioprotective mechanism of ginseng could be linked, either directly or indirectly, to its antioxidative capability by the scavenging free radicals responsible for DNA damage. In addition, ginseng's radioprotective potential may also be related to its immunomodulating capabilities. Ginseng is a natural product with worldwide distribution, and in addition to its antitumor properties, ginseng appears to be a promising radioprotector for therapeutic or preventive protocols capable of attenuating the deleterious effects of radiation on human normal tissue, especially for cancer patients undergoing radiotherapy.

Herbal remedies in the management of diabetes: lessons learned from the study of ginseng

The only example of an approved antidiabetic drug that was developed from a herbal source with a long history of use for diabetes is the biguanide Metformin from French lilac (Galega officinalis). Clinical data are beginning to emerge that support antidiabetic indications for several other herbs. This viewpoint discusses the state of the evidence for their clinical antidiabetic efficacy. One of the most studied herbs, ginseng (Panax spp.), is used as a model to illustrate the challenges associated with achieving reproducible clinical efficacy. It is concluded that the best evidence for clinical efficacy in diabetes remains for ginseng. But overall insufficient evidence exists to claim a diabetes indication for herbs. The experience with ginseng suggests that although reproducible efficacy may be achieved using an acute postprandial clinical screening model to select an efficacious ginseng batch, dose, and time of administration, there is a need to develop a basis for standardization that ties the composition of herbs to efficacy. In absence of such standardization, the use of herbs in diabetes must be approached cautiously.

Effects of Natural Health Products on Blood Pressure

OBJECTIVE:

To review the scientific literature to identify reports of the effects of natural health products (NHPs) on blood pressure. DATA SOURCES: Electronic databases (MEDLINE [1965–May 2004] via PubMed, the Cochrane Library [1995–May 2004], International Pharmaceutical Abstracts [1970–May 2004], Iowa Drug Information Services [1965–May 2004]) were searched using the key words medicine, herbal plants, medicinal plant preparations, phytotherapy, angiosperms/therapeutic use, gymnosperms/therapeutic use, ethnopharmacology, pharmacognosy, blood pressure, hypertension, hypotension, and diuretic. Searches were not limited by date, language, or publication type. Review articles and texts, as well as reference lists of relevant articles, were used to identify additional reports.

STUDY SELECTION AND DATA EXTRACTION:

Articles (English-language after 1980) were assigned to the following categories: human study, case report, animal study, in vitro study, or theoretical prediction based on chemical constituents. Discussions of mechanisms of action were noted.

DATA SYNTHESIS:

A comprehensive search of the scientific literature identified NHPs capable of affecting blood pressure. Case reports and clearly defined mechanisms of action provided strong evidence for the ability of ephedra and licorice to increase blood pressure. Coenzyme Q10 was reported to decrease systolic and diastolic blood pressure, although the mechanism is unclear. The clinical significance of the blood pressure effects of other NHPs is unclear due to lack of conclusive in vivo data, as well as substantial variability in the chemical content of preparations of NHPs.

CONCLUSIONS:

Among published information, there is little definitive evidence with regard to the impact of NHPs on blood pressure. Additionally, effects may vary in a given patient with the formulation and standardization of a particular product. Until research better characterizes the effect of NHPs on blood pressure, patients should be encouraged to talk with their healthcare provider before starting or stopping any herbal product.

Nitric oxide-dependent modulation of the delayed rectifier K+ current and the L-type Ca2+ current by ginsenoside Re, an ingredient of Panax ginseng, in guinea-pig cardiomyocytes

1 Ginsenoside Re, a major ingredient of Panax ginseng, protects the heart against ischemia-reperfusion injury by shortening action potential duration (APD) and thereby prohibiting influx of excessive Ca2+. Ginsenoside Re enhances the slowly activating component of the delayed rectifier K+ current (IKs) and suppresses the L-type Ca2+ current (I(Ca,L)), which may account for APD shortening. 2 We used perforated configuration of patch-clamp technique to define the mechanism of enhancement of IKs and suppression of I(Ca,L) by ginsenoside Re in guinea-pig ventricular myocytes. 3 S-Methylisothiourea (SMT, 1 microm), an inhibitor of nitric oxide (NO) synthase (NOS), and N-acetyl-L-cystein (LNAC, 1 mm), an NO scavenger, inhibited IKs enhancement. Application of an NO donor, sodium nitroprusside (SNP, 1 mm), enhanced IKs with a magnitude similar to that by a maximum dose (20 microm) of ginseonside Re, and subsequent application of ginsenoside Re failed to enhance IKs. Conversely, after IKs had been enhanced by ginsenoside Re (20 microm), subsequently applied SNP failed to further enhance IKs. 4 An inhibitor of guanylate cyclase, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 microm), barely suppressed IKs enhancement, while a thiol-alkylating reagent, N-ethylmaleimide (NEM, 0.5 mm), clearly suppressed it. A reducing reagent, di-thiothreitol (DTT, 5 mm), reversed both ginsenoside Re- and SNP-induced IKs enhancement. 5 I(Ca,L) suppression by ginsenoside Re (3 microm) was abolished by SMT (1 microm) or LNAC (1 mm). NEM (0.5 mm) did not suppress I(Ca,L) inhibition and DTT (5 mm) did not reverse I(Ca,L) inhibition, whereas in the presence of ODQ (10 microm), ginsenoside Re (3 microm) failed to suppress I(Ca,L). 6 These results indicate that ginsenoside Re-induced IKs enhancement and I(Ca,L) suppression involve NO actions. Direct S-nitrosylation of channel protein appears to be the main mechanism for IKs enhancement, while a cGMP-dependent pathway is responsible for I(Ca,L) inhibition.

Panax ginseng: a role in cancer therapy?

Panax ginseng is a plant that has been used in traditional medicine in China for thousands of years. It is used as a general tonic or adaptogen with chronically ill patients and is frequently featured in traditional medicine prescriptions from China, Japan, and Korea used by cancer patients. The putative active compounds are the ginsenosides, of which there are more than two dozen. These compounds are found in both Panax ginseng and in other Panax species that are used in herbal medicine. Analysis of ginsenosides is being used in developing quality control assessments for ginseng, which has frequently been adulterated due to its high cost; many currently available standardized extracts do appear to contain the amounts of ginsenosides listed on package labeling. The toxicity of ginseng appears to be low: some of the reports of toxic episodes of ginseng may actually pertain to other components of multicomponent preparations. Very low incidence of toxicity has been observed in ginseng clinical trials using well-characterized preparations. Numerous pharmacological activities of ginseng and the ginsenosides have been explored: the authors review here the activities relating to cancer. Immune system modulation, antistress activities, and antihyperglycemic activities are among the most notable features of ginseng noted in laboratory and clinical analyses. Much testing has been done in humans to explore ginseng's purported antifatigue properties, but this area remains controversial. A number of investigations point to antitumor properties and other pharmacological activities related to cancer, but no trials have yet confirmed a clinically significant anticancer activity. Cancer patients may empirically find ginseng to be useful when they are fatigued, although clinical trials should be conducted to confirm its benefits.