Co-administration of viscous fiber, Salba-chia and ginseng on glycemic management in type 2 diabetes: a double-blind randomized controlled trial.

PURPOSE: Viscous dietary fiber, functional seeds and ginseng roots have individually been proposed for the management of diabetes. We explored whether their co-administration would improve glycemic control in type 2 diabetes beyond conventional therapy. METHODS: In a randomized, double-blind, controlled trial conducted at two academic centers (Toronto, Canada and Zagreb, Croatia), individuals with type 2 diabetes were assigned to either an active intervention (10 g viscous fiber, 60 g white chia seeds, 1.5 g American and 0.75 g Korean red ginseng extracts), or energy and fiber-matched control (53 g oat bran, 25 g inulin, 25 g maltodextrose and 2.25 g wheat bran) intervention for 24 weeks, while on conventional standard of care. The prespecified primary endpoint was end difference at week 24 in HbA1c, following an intent-to-treat analysis adjusted for center and baseline. RESULTS: Between January 2016 and April 2018, 104 participants (60M:44F; mean ± SEM age 59 ± 0.8 years; BMI 29.0 ± 0.4 kg/m2; HbA1c 7.0 ± 0.6%) managed with antihyperglycemic agent(s) (n = 98) or lifestyle (n = 6), were randomized (n = 52 test; n = 52 control). At week 24, HbA1c levels were 0.27 ± 0.1% lower on test compared to control (p = 0.03). There was a tendency towards an interaction by baseline HbA1c (p = 0.07), in which a greater reduction was seen in participants with baseline HbA1c > 7% vs ≤ 7% (- 0.56 ± 0.2% vs 0.03 ± 0.2%). Diet and body weight remained unchanged. The interventions were well tolerated with no related adverse events and with high retention rate of 84%. CONCLUSIONS: Co-administration of selected dietary and herbal therapies was well-tolerated and may provide greater glycemic control as add-on therapy in type 2 diabetes. Registration: Clinicaltrials.gov NCT02553382 (registered on September 17, 2015).

Effect of viscous fiber supplementation on obesity indicators in individuals consuming calorie-restricted diets: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Dietary fiber has played a consistent role in weight management, with efficacy potentially attributed to increased viscous fiber consumption. PURPOSE: To summarize the effects of viscous fiber on body weight and other anthropometric parameters, along with a calorie-deficient diet, through a systematic review and meta-analysis. METHODS: MEDLINE, EMBASE, and the Cochrane library were searched through July 24, 2019 for randomized controlled trials that assessed the effect of viscous fiber supplementation as part of a restricted calorie diet for ≥ 4 weeks relative to comparator diets. Data were pooled using the generic inverse-variance method with random-effects models and expressed as mean differences with 95% confidence intervals. Inter-study heterogeneity was assessed using Cochran's Q and quantified with I2. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to evaluate the overall certainty of evidence. RESULTS: Findings from 15 studies (n = 1347) showed viscous fiber supplementation significantly decreased body weight (- 0.81 kg [- 1.20, - 0.41]; p < 0.0001), BMI (- 0.25 kg/m2 [- 0.46, - 0.05]; p = 0.01), and body fat (- 1.39% [- 2.61, - 0.17]; p = 0.03), compared to control. No effect on waist circumference was found. The certainty of evidence was graded as "moderate" for body weight, BMI, and body fat based on downgrades for imprecision. Waist circumference was graded "low" for downgrades of inconsistency and imprecision. CONCLUSION: Viscous fiber within a calorie-restricted diet significantly improved body weight and other markers of adiposity in overweight adults and those with additional risk factors for cardiovascular disease. This trial is registered at www.clinicaltrials.gov as NCT03257449. REGISTRATION: ClinicalTrials.gov identifier: NCT03257449.

Effect of soluble-viscous dietary fibre on coronary heart disease risk score across 3 population health categories: data from randomized, double-blind, placebo-controlled trials.

We applied the Framingham risk equation in healthy, metabolic syndrome, and diabetes populations, following treatment with viscous fibre from konjac-based blend (KBB). KBB yielded reduction in estimated risk score by 16% (1.04 ± 0.03 vs. 0.87 ± 0.04, p < 0.01) in type 2 diabetes, 24% (1.08 ± 0.01 vs. 0.82 ± 0.02, p < 0.01) in metabolic syndrome, and 25% (1.09 ± 0.05 vs. 0.82 ± 0.06, p < 0.01) in healthy individuals. Drivers for decreased risk were improvements in blood cholesterol and systolic blood pressure. The composite coronary heart disease risk across populations was reduced 22% (p < 0.01). Novelty Viscous fibre from konjac-xanthan reduced 10-year relative coronary heart disease using Framingham Risk Score across the glycemic status spectrum.

Vascular effects of combined enriched Korean Red ginseng (Panax Ginseng) and American ginseng (Panax Quinquefolius) administration in individuals with hypertension and type 2 diabetes: A randomized controlled trial.

BACKGROUND: Type 2 diabetes is known to abrogate the vascular response. Combination of two commonly consumed ginseng species, American ginseng (AG) and a Korean Red ginseng (KRG), enriched with ginsensoide Rg3, was shown to concomitantly improve glucemic control and blood pressure. We evaluated the hypothesis that improvements in central hemodynamics, vascular function and stiffness markers are involved in observed benefits of co-administration. METHODS: In this randomized, placebo controlled, two-center trial, patients with type 2 diabetes and hypertension were assigned to either 2.25 g ginsenoside Rg3-enriched KRG&AG co-administration or a control 3 times daily for 12-weeks, treated by standard of care. The effects on central hemodynamics, pulse wave velocity (PWV) and endothelial function over the 12-week administration were analyzed. RESULTS: In intent-to-treat analysis of 80 individuals, a reduction in central systolic BP (-4.69 ±â€¯2.24 mmHg, p = 0.04) was observed with co-administration of Rg3-KRG + AG relative to control at 12-weeks, which was characterized by a decrease in end-systolic pressure (-6.60 ±â€¯2.5 mmHg, p = 0.01) and area under the systolic/diastolic BP curve (-132.80 ±â€¯65.1, p = 0.04, 220.90 ±â€¯91.1, p = 0.02, respectively). There was no significant change in reactive hyperemia index (0.09 ±â€¯0.11, p = 0.44), PWV (-0.40 ±â€¯0.28 %, p = 0.17), and other related pulse wave analysis components. CONCLUSION: Co-administration of complementary ginseng species improved central systolic BP and components of pulse waveform without a direct effect on endothelial function, when added to background pharmacotherapy in individuals with diabetes. These data support potential utility of ginseng for modest blood pressure benefit to broaden its role in diabetes management.

Should Viscous Fiber Supplements Be Considered in Diabetes Control? Results From a Systematic Review and Meta-analysis of Randomized Controlled Trials.

OBJECTIVE: Evidence from randomized controlled trials (RCTs) suggests that viscous dietary fiber may offer beneficial effects on glycemic control and, thus, an improved cardiovascular disease risk profile. Our purpose was to conduct a systematic review and meta-analysis of RCTs to synthesize the therapeutic effect of viscous fiber supplementation on glycemic control in type 2 diabetes. RESEARCH DESIGN AND METHODS: MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were searched through 15 June 2018. We included RCTs ≥3 weeks in duration that assessed the effects of viscous fiber on markers of glycemic control in type 2 diabetes. Two independent reviewers extracted data. Data were pooled using the generic inverse variance method and expressed as mean differences (MD) with 95% CIs. Heterogeneity was assessed (Cochran Q statistic) and quantified (I 2 statistic). The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to evaluate the overall certainty of the evidence. RESULTS: We identified 28 eligible trial comparisons (n = 1,394). Viscous fiber at a median dose of ∼13.1 g/day significantly reduced HbA1c (MD -0.58% [95% CI -0.88, -0.28]; P = 0.0002), fasting blood glucose (MD -0.82 mmol/L [95% CI -1.32, -0.31]; P = 0.001), and HOMA-insulin resistance (IR) (MD -1.89 [95% CI -3.45, -0.33]; P = 0.02) compared with control and in addition to standard of care. The certainty of evidence was graded moderate for HbA1c, fasting glucose, fasting insulin, and HOMA-IR and low for fructosamine. CONCLUSIONS: Viscous fiber supplements improve conventional markers of glycemic control beyond usual care and should be considered in the management of type 2 diabetes.

Efficacy and safety of American ginseng (Panax quinquefolius L.) extract on glycemic control and cardiovascular risk factors in individuals with type 2 diabetes: a double-blind, randomized, cross-over clinical trial.

PURPOSE: Despite the lack of evidence, a growing number of people are using herbal medicine to attenuate the burden of diabetes. There is an urgent need to investigate the clinical potential of herbs. Preliminary observations suggest that American ginseng (Panax quinquefolius [AG]) may reduce postprandial glycemia. Thus, we aimed to evaluate the efficacy and safety of AG as an add-on therapy in individuals with type 2 diabetes (T2DM) controlled by conventional treatment. METHODS: 24 individuals living with T2DM completed the study (F:M = 11:13; age = 64 ± 7 year; BMI = 27.8 ± 4.6 kg/m2; HbA1c = 7.1 ± 1.2%). Utilizing a double-blind, cross-over design, the participants were randomized to receive either 1 g/meal (3 g/day) of AG extract or placebo for 8 weeks while maintaining their original treatment. Following a ≥ 4-week washout period, the participants were crossed over to the opposite 8-week treatment arm. The primary objective was HbA1c, and secondary endpoints included fasting blood glucose and insulin, blood pressure, plasma lipids, serum nitrates/nitrites (NOx), and plasominogen-activating factor-1 (PAI-1). Safety parameters included liver and kidney function. RESULTS: Compared to placebo, AG significantly reduced HbA1c (- 0.29%; p = 0.041) and fasting blood glucose (- 0.71 mmol/L; p = 0.008). Furthermore, AG lowered systolic blood pressure (- 5.6 ± 2.7 mmHg; p < 0.001), increased NOx (+ 1.85 ± 2.13 µmol/L; p < 0.03), and produced a mean percent end-difference of - 12.3 ± 3.9% in LDL-C and - 13.9 ± 5.8% in LDL-C/HDL. The safety profiles were unaffected. CONCLUSIONS: AG extract added to conventional treatment provided an effective and safe adjunct in the management of T2DM. Larger studies using physiologically standardized ginseng preparations are warranted to substantiate the present findings and to demonstrate therapeutic effectiveness of AG. CLINICALTRIALS. GOV IDENTIFIER: NCT02923453.

Effect of psyllium (Plantago ovata) fiber on LDL cholesterol and alternative lipid targets, non-HDL cholesterol and apolipoprotein B: a systematic review and meta-analysis of randomized controlled trials.

Background: Studies have identified viscous dietary fiber as potentially attenuating cholesterol, including psyllium, which reduces LDL cholesterol and thus may complement cardiovascular disease (CVD) treatment. Objectives: The aims of this study were to update evidence on the effect of psyllium on LDL cholesterol and to provide an assessment of its impact on alternate markers: non-HDL cholesterol and apolipoprotein B (apoB). Design: Medline, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials were searched through 3 October 2017. Independent reviewers extracted relevant data and assessed risk of bias. We included randomized controlled trials with a duration of ≥3 wk that assessed the effect of psyllium on blood lipids in individuals with or without hypercholesterolemia. Data were pooled by using the generic inverse variance method with random-effects models and expressed as mean differences (MDs) with 95% CIs. Heterogeneity was assessed by Cochran's Q statistic and quantified by the I2 statistic. Overall quality of the evidence was assessed by using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach. Results: We included 28 trials in our analysis (n = 1924). Supplementation of a median dose of ∼10.2 g psyllium significantly reduced LDL cholesterol (MD = -0.33 mmol/L; 95% CI: -0.38, -0.27 mmol/L; P < 0.00001), non-HDL cholesterol (MD = -0.39 mmol/L; 95% CI: -0.50, -0.27 mmol/L; P < 0.00001), and apoB (MD = -0.05 g/L; 95% CI: -0.08, -0.03 g/L; P < 0.0001). Effect estimates for LDL cholesterol and non-HDL cholesterol were graded as moderate quality on the basis of downgrades for inconsistency and graded as high quality for apoB. Conclusion: Psyllium fiber effectively improves conventional and alternative lipids markers, potentially delaying the process of atherosclerosis-associated CVD risk in those with or without hypercholesterolemia. This trial is registered at www.clinicaltrials.gov as NCT03346733.

Co-administration of a konjac-based fibre blend and American ginseng (Panax quinquefolius L.) on glycaemic control and serum lipids in type 2 diabetes: a randomized controlled, cross-over clinical trial.

PURPOSE: Use of polypharmacy in the treatment of diabetes is the norm; nonetheless, optimal control is often not achieved. Konjac-glucomannan-based fibre blend (KGB) and American ginseng (AG) have individually been shown to improve glycaemia and CVD risk factors in type 2 diabetes. The aim of this study was to determine whether co-administration of KGB and AG could improve diabetes control beyond conventional treatment. METHOD: Thirty-nine participants with type 2 diabetes (6.5 > A1c < 8.4%) were enrolled between January 2002 and May 2003 at the Risk Factor Modification Centre at St Michaels Hospital in a randomized, placebo-controlled, crossover trial with each intervention lasting 12-weeks. Medications, diet and lifestyle were kept constant. Interventions consisted of 6 g of fibre from KGB together with 3 g of AG (KGB and AG) or wheat bran-based, fibre-matched control. Primary endpoint was the difference in HbA1c levels at week 12. RESULTS: Thirty participants (18M:12F; age: 64 ± 7 years; BMI: 28 ± 5 kg/m2; HbA1c: 7.0 ± 1.0%) completed the study, and consumed 5.5 and 4.9 g/day of fibre from KGB and wheat bran control, respectively, and 2.7 g/day of AG. At week 12, HbA1c levels were 0.31% lower on the KGB and AG compared to control (p = 0.011). Mean (±SEM) plasma lipids decreased on the KGB and AG vs control by 8.3 ± 3.1% in LDL-C (p = 0.002), 7.5 ± 2.4% in non-HDL-C (p = 0.013), 5.7 ± 1.9% in total-C (p = 0.012), 4.1 ± 2.1% in total-C:HDL-C ratio (p = 0.042), 9.0 ± 2.3% in ApoB (p = 0.0005) and 14.6 ± 4.2% in ApoB:ApoA1 ratio (p = 0.049). CONCLUSIONS: Co-administration of KGB and AG increases the effectiveness of conventional therapy through a moderate but clinically meaningful reduction in HbA1c and lipid concentrations over 12 weeks in patients with type 2 diabetes. CLINICAL TRIALS REGISTRATION: NCT02806349 ( https://clinicaltrials.gov/ ).

The effect of oat ß-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for CVD risk reduction: a systematic review and meta-analysis of randomised-controlled trials.

Oats are a rich source of ß-glucan, a viscous, soluble fibre recognised for its cholesterol-lowering properties, and are associated with reduced risk of CVD. Our objective was to conduct a systematic review and meta-analysis of randomised-controlled trials (RCT) investigating the cholesterol-lowering potential of oat ß-glucan on LDL-cholesterol, non-HDL-cholesterol and apoB for the risk reduction of CVD. MEDLINE, Embase, CINAHL and Cochrane CENTRAL were searched. We included RCT of ≥3 weeks of follow-up, assessing the effect of diets enriched with oat ß-glucan compared with controlled diets on LDL-cholesterol, non-HDL-cholesterol or apoB. Two independent reviewers extracted data and assessed study quality and risk of bias. Data were pooled using the generic inverse-variance method with random effects models and expressed as mean differences with 95 % CI. Heterogeneity was assessed by the Cochran's Q statistic and quantified by the I 2-statistic. In total, fifty-eight trials (n 3974) were included. A median dose of 3·5 g/d of oat ß-glucan significantly lowered LDL-cholesterol (-0·19; 95 % CI -0·23, -0·14 mmol/l, P<0·00001), non-HDL-cholesterol (-0·20; 95 % CI -0·26, -0·15 mmol/l, P<0·00001) and apoB (-0·03; 95 % CI -0·05, -0·02 g/l, P<0·0001) compared with control interventions. There was evidence for considerable unexplained heterogeneity in the analysis of LDL-cholesterol (I 2=79 %) and non-HDL-cholesterol (I 2=99 %). Pooled analyses showed that oat ß-glucan has a lowering effect on LDL-cholesterol, non-HDL-cholesterol and apoB. Inclusion of oat-containing foods may be a strategy for achieving targets in CVD reduction.

Ethanol extraction preparation of American ginseng (Panax quinquefolius L) and Korean red ginseng (Panax ginseng C.A. Meyer): differential effects on postprandial insulinemia in healthy individuals.

ETHNOPHARMACOLOGICAL RELEVANCE: Ginsenosides are the proposed bioactive constituent of ginseng, especially for the attenuation of postprandial glycemia (PPG). The efficacious proportion of total and specific ginsenosides, remains unknown. Alcohol extraction of whole ginseng root can be used to selectively manipulate the ginsenoside profile with increasing alcohol concentrations producing high yields of total ginsenosides and varying their individual proportions. AIM OF THE STUDY: We aimed to compare the acute efficacy of different ethanol-extraction preparations of American ginseng (AG) and Korean red ginseng (KRG), with their whole-root origins, on PPG and insulin parameters in healthy adults. MATERIALS AND METHODS: Following an overnight fast, 13 healthy individuals (Gender: 5M:8F, with mean ± SD, age: 28.9 ± 9.2 years, BMI: 26.3 ± 2.7 kg/m(2) and fasting plasma glucose: 4.21 ± 0.04 mmol/L) randomly received 3g of each of the following 10 different ginseng treatments on separate visits: whole root KRG and AG; 30%, 50% or 70% ethanol extracts of KRG and AG and 2 cornstarch placebos. Treatments were consumed 40 min prior to a 50 g oral glucose challenge test with capillary blood samples collected at baseline, 15, 30, 45, 60, 90 and 120 min. Insulin samples were collected at 0, 30, 60 and 120 min. RESULTS: There was no difference in attenuation of PPG among the tested ginseng preparations. Measures of Insulin Sensitivity Index (ISI) showed increased insulin sensitivity (IS) with KRG-30% and AG-50% extracts compared to placebo (p<0.05). CONCLUSIONS: The insulin sensitizing effects of KRG-30% and AG-50% extracts suggest that other root parts, including other ginsenosides not typically measured, may influence PPG and insulin parameters. There is potential for AG and KRG extracts to modulate IS, an independent predictor of type 2 diabetes.

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.

Effect of Rg3-enriched Korean red ginseng (Panax ginseng) on arterial stiffness and blood pressure in healthy individuals: a randomized controlled trial.

Ginsenoside Rg3, present in steamed ginseng (Panax Ginseng C.A. Meyer), is thought to be a potent modulator of vascular function. Our objective was to clinically evaluate acute effects of ginsenoside Rg3-enriched Korean red ginseng (Rg3-KRG) on measures of arterial stiffness and peripheral and central blood pressure (BP) parameters in healthy volunteers. Using a double-blind, randomized, crossover design, 23 individuals (9 males:14 females; age, 25 ± 2 years; body mass index, 22 ± 0.6 kg/m(2); systolic BP/diastolic BP, 113 ± 3/70 ± 2 mm Hg) were administered 400-mg Rg3-KRG extract or 400-mg wheat bran control on two separate visits with a 7-day washout period. Aortic augmentation index and central BP were measured using applanation tonometry by radial pulse wave analysis, and peripheral BP was evaluated oscillometrically. Measurements were taken at baseline and at 1, 2, and 3 hours after intervention. Compared with control, there were significant reductions in augmentation index (-4.3 ± 8.9%, P = .03), central (-4.8 ± 6.8 mm Hg, P = .01) and brachial mean arterial pressure (-4.4 ± 6.6 mm Hg, P = .01), central systolic (-5.0 ± 7.9 mm Hg, P = .01) and diastolic BP (-3.9 ± 6.6 mm Hg, P = .01), and brachial systolic (-4.4 ± 10.0 mm Hg, P = .048) and diastolic BP (-3.6 ± 6.4 mm Hg, P = .01) at 3 hours after intervention compared with control. This study is the first to demonstrate Rg3-KRG extract acutely lowers central and peripheral arterial pressures in healthy adults. Further clinical evaluation is desired to quantify efficacy in higher risk individuals and in long-term settings.

American Ginseng Extract (Panax quinquefolius L.) Is Safe in Long-Term Use in Type 2 Diabetic Patients.

Aim. The objective of the present study was to test the safety of supplementation with the American ginseng (AG) interventional material as an adjunct to conventional therapy (diet and/or medications) in type 2 diabetes, using a double-blind, randomized, placebo-controlled, parallel design. Methods. Each participant received either AG (10% ginsenosides) or placebo capsules (500 mg/meal = 3 g/day) for a period of 12 weeks. Outcomes included measures of safety including kidney function (urates and creatinine), liver function (AST and ALT), and haemostatic function (PV and INR). Results. Seventy-four participants with well-controlled type 2 diabetes (sex: 28 M and 46 F, age: 63 ± 9.5, BMI: 32 ± 5, and HbA1c: 7 ± 1.3), randomized to either intervention (n = 35) or control (n = 39) group, completed the study. There was no change in any of the measures of safety between treatments from baseline. The number or severity of adverse events did not differ between the AG intervention and placebo. Conclusion. Following 12 weeks of supplementation with AG, safety was not compromised in a high cardiovascular disease (CVD) risk population of patients with type 2 diabetes. This demonstrated that safety is noteworthy, as reviews have continuously warned of possible adverse effects of ginseng consumption.

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.

Effect of American ginseng (Panax quinquefolius L.) on arterial stiffness in subjects with type-2 diabetes and concomitant hypertension.

ETHNOPHARMACOLOGICAL RELEVANCE: Substantial pre-clinical and some clinical data are available showing that Asian ginseng (Panax ginseng C.A. Meyer) varieties or its particular ginsenosides exert a vasodilatating effect, thus may modulate vascular function. However, the clinical evidence for American ginseng (Panax quinquefolius L.) is scarce. Therefore, this study evaluates the effect of American ginseng (AG) on arterial stiffness, as measured by augmentation index (AI), and blood pressure (BP), in type 2 diabetes patients with concomitant hypertension. MATERIALS AND METHODS: Using a double-blind, placebo-controlled, parallel design, each participant was randomized to either the selected AG extract or placebo at daily dose of 3g for 12 weeks as an adjunct to their usual antihypertensive and anti-diabetic therapy (diet and/or medications). AI and BP were measured by applanation tonometry at baseline and after 12 weeks of treatment. RESULTS: A total of 64 individuals with well-controlled essential hypertension and type 2 diabetes (gender: 22 M:42 F, age:63 ± 9.3 years, BP: 145 ± 10.8/84 ± 8.0 mmHg, HbA1c: 7.0 ± 1.3%, fasting blood glucose (FBG): 8.1 ± 2.3 mmol/L) completed the study. Compared to placebo, 3g of AG significantly lowered radial AI by 5.3% (P=0.041) and systolic BP by 11.7% (P<0.001) at 12 weeks. No effect was observed with diastolic BP. CONCLUSIONS: Addition of AG extract to conventional therapy in diabetes with concomitant hypertension improved arterial stiffness and attenuated systolic BP, thus warrants further investigation on long-term endothelial parameters before recommended as an adjunct treatment.

Effect of American ginseng (Panax quinquefolius L.) on glycemic control in type 2 diabetes.

Since diabetes tends to progressively worsen over time, glycemic control often deteriorates in spite of taking regular therapy. Therefore, numerous research studies are by and large focused on finding more efficient therapy, both new medicines for treating type 2 diabetes mellitus, as well as supplements that could serve as an addition to conventional treatment modalities. A variety of herbal preparations have been shown to have modest short-term beneficial effects on glycemia, but of these, the best studied is American ginseng (AG). AG has been shown to be effective in improving glycemic control in type 2 diabetes through increasing post-prandial insulin levels and decreasing postprandial glycemic response. However, high variability in ginsenosides may result in just as high variability in antidiabetic efficacy of over-the-counter ginseng products. Therefore, the availability of standardized extracts of AG could assist greatly in advancing our knowledge on the role of this traditionally used herb and result in a wider application of ginseng product in diabetes management. The aim of this review is to outline the efficacy and safety of American ginseng for AG preparations on glycemic control in patients with type 2 diabetes as well as to increase awareness of the evidence supporting the use of these therapies in diabetes care.

Viscosity rather than quantity of dietary fibre predicts cholesterol-lowering effect in healthy individuals.

The well-documented lipid-lowering effects of fibre may be related to its viscosity, a phenomenon that has been understudied, especially when fibre is given against the background of a typical North American (NA) diet. In this three-arm experiment, we compared the lipid-lowering effect of low-viscosity wheat bran (WB), medium-viscosity psyllium (PSY) and a high-viscosity viscous fibre blend (VFB), as part of a fibre intervention aimed at increasing fibre intake to recommended levels within the context of a NA diet in apparently healthy individuals. Using a randomised cross-over design, twenty-three participants (twelve males and eleven females; age 35 (SD 12) years; LDL-cholesterol (C) 2.9 (SEM 0.6) mmol/l) consuming a typical NA diet received a standard, fibre-enriched cereal, where approximately one-third of the fibre was either a low-viscosity (570 centipoise (cP)) WB, medium-viscosity (14,300 cP) PSY or a high-viscosity (136,300 cP) novel VFB, for 3 weeks separated by washout periods of ≥ 2 weeks. There were no differences among the treatments in the amount of food consumed, total dietary fibre intake, reported physical activity and body weight. Final intake of the WB, PSY and VFB was 10.8, 9.0 and 5.1 g, respectively. Reduction in LDL-C was greater with the VFB compared with the medium-viscosity PSY (-12.6 (SEM 3.5) %, P = 0.002) and low-viscosity WB (-14.6 (SEM 4.2) %, P = 0.003). The magnitude of LDL-C reduction showed a positive association with fibre apparent viscosity (r - 0.41, P = 0.001). Despite the smaller quantity consumed, the high-viscosity fibre lowered LDL-C to a greater extent than lower-viscosity fibres. These data support the inclusion of high-viscosity fibre in the diet to reduce plasma lipids among apparently healthy individuals consuming a typical NA diet.

Korean red ginseng (Panax ginseng C.A. Meyer) root fractions: differential effects on postprandial glycemia in healthy individuals.

ETHNOPHARMACOLOGICAL RELEVANCE: Variations in ginsenoside profile may predict the postprandial glucose (PPG)-lowering efficacy of ginseng. Previously we reported differential PPG-lowering effects with two Korean red ginseng (KRG) root. FRACTIONS: body and rootlets, of variable ginsenoside profiles. Whether this effect is reproducible with a different KRG source is unclear. We therefore tested two root fractions from a KRG source with elevated ginsenoside levels to assess its effect on PPG. MATERIALS AND METHODS: After a 12-h overnight fast, 13 healthy individuals (6M:7F; age=28 ± 10 y; BMI=24.1 ± 3 kg/m2; FBG=4.77 ± 0.04 mmol/L) randomly received either 3g of KRG-body, rootlets or placebo, on three separate visits. Treatments were consumed 60 min prior to a standard test meal with capillary blood samples at -60, 0, 15, 30, 45, 60, 90 and 120 min. RESULTS: The KRGrootlets had>6 fold total ginsensosides than the KRG-body but did not significantly affect PPG. Despite a reduced ginsenoside profile, KRG-body lowered PPG levels at 45, 60, 90 and 120 min during the test (p<0.05), rendering an overall reduction of 27% in incremental area under the glucose curve compared to the control (p<0.05). CONCLUSIONS: Comparing the results with a previously studied batch of KRG suggests a potential therapeutic dose range for ginsenosides. This observation should be clinically verified with acute screening and ginsenoside composition analysis.

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.