American ginseng supplementation induces an oxidative stress in postmenopausal women

Effects of ginseng consumption on the biomarkers of oxidative stress: A systematic review and meta-analysis

Oxidative stress (OS) is a key factor involved in the initiation and development of chronic diseases. Despite its widespread acceptance as an antioxidant, the effects of ginseng on OS in human clinical trials have not been comprehensively analyzed. Therefore, this study aimed to synthesize the results of previous randomized clinical trials (RCTs) examining the impact of ginseng consumption on OS indicators. PubMed, Web of Science, Scopus, and Cochrane databases were searched for articles on the effects of ginseng consumption on oxidative stress markers up to March 20, 2023. Standardized mean difference (SMD) and 95% confidence intervals (CIs) were used to assess effect sizes. Twelve RCTs with 15 effect sizes revealed that the effects of ginseng lowered serum malondialdehyde (MDA) levels (SMD = 0.45, 95% CI: -0.87, -0.08; p = 0.03) and significantly increased the serum total antioxidant capacity (TAC) (SMD = 0.23, 95% CI: 0.01, 0.45; p = 0.04), oxidative dismutase (SOD) (SMD = 0.39, 95% CI: 0.21, 0.57; p < 0.0001), glutathione (GSH) (SMD = 0.36; 95% CI: 0.11, 0.61; p = 0.005), and glutathione reductase (GR) (SMD = 0.56; 95% CI: 0.31, 0.81; p < 0.0001) levels compared to the effects of placebo. However, the effects on serum glutathione peroxidase (GPx) and catalase (CAT) were not significant. Moreover, subgroup analysis based on intervention duration showed that ginseng consumption increased GPx (SMD = 0.91, 95% CI: 0.05, 1.78; p = 0.039) and CAT (SMD = 0.74, 95% CI: 0.27, 1.21; p = 0.002) levels after more than 4 weeks of intervention. According to the results of this meta-analysis, ginseng supplementation dramatically reduced MDA levels and increased TAC, SOD, GSH, and GR levels. Our results open up a new line of defense against oxidative stress-induced diseases.

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: A Qualitative Review of Benefits for Palliative Clinicians

Ginseng has been used for centuries to treat various diseases and has been commercially developed and cultivated in the past 300 years. Ginseng products may be fresh, dried (white), or dried and steamed (red). Extracts may be made using water or alcohol. There are over 50 different ginsenosides identified by chromatography. We did an informal systematic qualitative review that centered on fatigue, cancer, dementia, respiratory diseases, and heart failure, and we review 113 studies in 6 tables. There are multiple potential benefits to ginseng in cancer. Ginseng, in certain circumstances, has been shown to improve dementia, chronic obstructive pulmonary disease, and heart failure through randomized trials. Most trials had biases or unknown biases and so most evidence is of low quality. We review the gaps in the evidence and make some recommendations regarding future studies.

Hormetic Property of Ginseng Steroids on Anti-Oxidant Status against Exercise Challenge in Rat Skeletal Muscle

Background: Existing literature on anti-oxidant capacity of ginseng has been inconsistent due to variance in the profile of ginseng steroids (Ginsenosides) that is because of differences in seasons and species. Methods: We used various doses of ginseng steroids to determine its effect on oxidative stress and anti-oxidant capacity of rat skeletal muscle against exercise. Results: Under non-exercise conditions, we found increased thiobarbituric acid reactive substance (TBARS) levels and decreased reduced/oxidized glutathione ratio (GSH/GSSG) in rat skeletal muscle as dose increases (p < 0.05), which indicates the pro-oxidant property of ginseng steroids at baseline. Intriguingly, exhaustive exercise-induced increased TBARS and decreased GSH/GSSG ratio were attenuated with low and medium doses of ginseng steroids (20 and 40 mg per kg), but not with high dose (120 mg per kg). At rest, anti-oxidant enzyme activities, including catalase (CAT), glutathione reductase (GR) and glutathione S-transferase (GST) were increased above vehicle-treated level, but not with the high dose, suggesting a hormetic dose-response of ginseng steroids. Conclusion: The results of this study provide an explanation for the inconsistent findings on anti-oxidative property among previous ginseng studies. For optimizing the anti-oxidant outcome, ginseng supplementation at high dose should be avoided.

Ginseng for managing menopausal woman's health: A systematic review of double-blind, randomized, placebo-controlled trials

BACKGROUND

The aim of this systematic review was to update, complete, and critically evaluate the evidence from placebo-controlled randomized clinical trials (RCTs) of ginseng for managing menopausal women's health.

METHODS

We searched the literature using 13 databases (MEDLINE, AMED, EMBASE, the Cochrane Library, 6 Korean Medical, and 3 Chinese Databases) from their inception to July 2016 and included all double-blind RCTs that compared any type of ginseng with a placebo control in postmenopausal women. The methodological quality of all studies was assessed using a Cochrane risk of bias tool.

RESULTS

Ten RCTs met our inclusion criteria. Most RCTs had unclear risk of bias. One RCT did not show a significant difference in hot flash frequency between Korean red ginseng (KRG) and placebo. The second RCT reported positive effects of KRG on menopausal symptoms. The third RCT found beneficial effects of ginseng (Ginsena) on depression, well-being, and general health. Four RCTs failed to show significant differences in various hormones between KRG and placebo controls except dehydroepiandrosterone. Two other RCTs failed to show effects of KRG on endometrial thickness in menopausal women. The other RCT also failed to show the effects of American ginseng on oxidative stress markers and other antioxidant enzymes.

CONCLUSION

Our systematic review provided positive evidence of ginseng for sexual function and KRG for sexual arousal and total hot flashes score in menopausal women. However, the results of KRG or ginseng failed to show specific effects on hot flash frequency, hormones, biomarkers, or endometrial thickness. The level of evidence for these findings was low because of unclear risk of bias.

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.

The effect of ginseng (the genus panax) on glycemic control: a systematic review and meta-analysis of randomized controlled clinical trials

Importance

Despite the widespread use of ginseng in the management of diabetes, supporting evidence of its anti-hyperglycemic efficacy is limited, necessitating the need for evidence-based recommendations for the potential inclusion of ginseng in diabetes management.

Objective

To elucidate the effect of ginseng on glycemic control in a systematic review and meta-analysis of randomized controlled trials in people with and without diabetes.

Data sources

MEDLINE, EMBASE, CINAHL and the Cochrane Library (through July 3, 2013).

Study selection

Randomized controlled trials ≥30 days assessing the glycemic effects of ginseng in people with and without diabetes.

Data extraction

Relevant data were extracted by 2 independent reviewers. Discrepancies were resolved by consensus. The Heyland Methodological Quality Score and the Cochrane risk of bias tool were used to assess study quality and risk of bias respectively.

Data synthesis

Sixteen trials were included, in which 16 fasting blood glucose (n = 770), 10 fasting plasma insulin (n = 349), 9 glycated hemoglobin (n = 264), and 7 homeostasis model assessment of insulin resistance (n = 305) comparisons were reported. Ginseng significantly reduced fasting blood glucose compared to control (MD =  −0.31 mmol/L [95% CI: −0.59 to −0.03], P = 0.03). Although there was no significant effect on fasting plasma insulin, glycated hemoglobin, or homeostasis model assessment of insulin resistance, a priori subgroup analyses did show significant reductions in glycated hemoglobin in parallel compared to crossover trials (MD = 0.22% [95%CI: 0.06 to 0.37], P = 0.01).

Limitations

Most trials were of short duration (67% trials<12wks), and included participants with a relatively good glycemic control (median HbA1c non-diabetes = 5.4% [2 trials]; median HbA1c diabetes = 7.1% [7 trials]).

Conclusions

Ginseng modestly yet significantly improved fasting blood glucose in people with and without diabetes. In order to address the uncertainty in our effect estimates and provide better assessments of ginseng's anti-diabetic efficacy, larger and longer randomized controlled trials using standardized ginseng preparations are warranted.

Trial Registration

ClinicalTrials.gov NCT01841229

Antioxidative effects of Korean red ginseng in postmenopausal women: a double-blind randomized controlled trial

ETHNOPHARMACOLOGICAL RELEVANCE

Red ginseng (RG) has been widely used to treat various diseases in East Asian countries. Previous studies have shown the anti-oxidative and anti-diabetic effects of RG. This study aimed to investigate the effects of RG on oxidative stress and insulin resistance in postmenopausal women.

MATERIALS AND METHODS

We performed a randomized, double-blind, placebo-controlled trial in 82 postmenopausal women aged 45-60 years. Participants were randomized to receive 3g red ginseng daily or placebo for 12 weeks. Antioxidant enzymes activity (superoxide dismutase, glutathione peroxidase) and oxidative stress markers (malondialdehyde, 8-hydroxydeoxyguanosine) were assessed, and the homeostatic model assessment of insulin resistance index was calculated at the baseline and at the end of the trial.

RESULTS

A total of 71 postmenopausal women completed the study. Serum superoxide dismutase activity was significantly increased after the 12-week RG supplementation (P<0.001), and these changes were statistically significant compared with the placebo group (P=0.004). Serum malondialdehyde levels showed a tendency to decrease after the 12-week RG supplementation (P=0.001), but these changes were not statistically significant compared with the placebo group (P=0.064). No statistically significant changes in serum glutathione peroxidase and 8-hydroxydeoxyguanosine were noted. Further, RG supplementation showed no effects on fasting glucose, fasting insulin, and insulin resistance.

CONCLUSIONS

The results suggest that RG may reduce oxidative stress by increasing antioxidant enzyme activity in postmenopausal women.

Trends in ginseng research in 2010

A total of 470 papers directly related to research on the Panax species were retrieved by performing internet searches with the keywords Panax and ginseng as the search terms. The publications were categorized as follows: 399 research articles, 30 reviews, 30 meeting abstracts, 7 proceedings, and 4 letters. The majority of these publications were published by scientists from Korea (35.7%), China (32.3%), and the USA (11.3%). Scientists from a total of 29 nations were actively involved in conducting ginseng research. A total of 43.6% of the publications were categorized as pharmacodynamic studies. The effects of ginseng on cerebrovascular function and cancer were the two most common topics considered in the pharmacodynamic studies. More than half of the ginseng studies assessed the use of P. ginseng. A total of 23 countries participated in studies specifically related to P. ginseng, and more than 80% of these studies originated from Korea and China. A total of 50 topics within the pharmacodynamics category were examined in association with the use of P. ginseng.

Avenanthramides are bioavailable and accumulate in hepatic, cardiac, and skeletal muscle tissue following oral gavage in rats

Avenanthramides (AVA), polyphenols found exclusively in oats ( Avena sativa L.), may play a role in the anti-inflammatory and antiatherogenic activity of oats. The bioavailability of AVA has been demonstrated previously, but its distribution at the organ and tissue level and the extent of conjugation following ingestion have been unexplored. Synthetic AVA was administered to 24 rats by oral gavage, whereas 6 control rats received saline. AVA concentrations were measured via HPLC in plasma, liver, heart, and gastrocnemius (GAS) obtained over a 12 h period (0, 2, 4, 12 h; n = 6 at each time point). Samples were extracted with and without glucuronidase-sulfatase to assess the level of conjugation. We conclude that AVA are bioavailable to the blood circulation following oral ingestion in the rat and reach peripheral tissues where they can be taken up by various organs differentially. With AVA remaining in the organs for up to 12 h, it seems possible to maintain an increased level of AVA in the rat via repeated feedings.

Antioxidant effects of Panax ginseng C.A. Meyer in healthy subjects: a randomized, placebo-controlled clinical trial

We investigated the antioxidant effects of Panax ginseng C.A. Meyer on healthy volunteers. In a double-blind randomized controlled design, 82 participants (21 men and 61 women) who were considered healthy by both objective and subjective health standard were divided into three groups, the control group and the groups received P. ginseng extract (1 or 2g/day) for 4 weeks. Serum level of reactive oxygen species (ROS), malondialdehyde (MDA), total antioxidant capacity (TAC), the activities of catalase, superoxide dismutase (SOD), glutathione reductase (GSH-Rd), and peroxidase (GSH-Px), and total glutathione content were determined before and after the trial. Administration of P. ginseng led to significant decreases in the levels of serum ROS and MDA. Notably, the total glutathione content and GSH-Rd activity considerably improved in the groups that received 2g of P. ginseng. No significant alterations were observed in TAC, catalase, SOD, and GSH-Px activities. In conclusion, our findings indicate that P. ginseng was shown to have antioxidant property. It enhanced the antioxidant defense mechanism in healthy populations and the results may reinforce the use of P. ginseng as a potential antioxidant supplement.