Effect of Spinach, a High Dietary Nitrate Source, on Arterial Stiffness and Related Hemodynamic Measures: A Randomized, Controlled Trial in Healthy Adults

( Elena Jovanovski ),( Laura Bosco ),( Kashif Khan ),( Au Yeung Fei ),( Hoang Ho ),( Andreea Zurbau ),( Alexandra L. Jenkins ),( Vladimir Vuksan ) 한국임상영양학회 2015 Clinical Nutrition Research Vol.4 No.3

Diets rich in fruits and vegetables reduce risk of adverse cardiovascular events. However, the constituents responsible for this effect have not been well established. Lately, the attention has been brought to vegetables with high nitrate content with evidence that this might represent a source of vasoprotective nitric oxide. We hypothesized that short-term consumption of spinach, a vegetable having high dietary nitrate content, can affect the arterial waveform indicative of arterial stiffness, as well as central and peripheral blood pressure (BP). Using a placebo-controlled, crossover design, 27 healthy participants were randomly assigned to receive either a high-nitrate (spinach; 845 mg nitrate/day) or low-nitrate soup (asparagus; 0.6 mg nitrate/day) for 7 days with a 1-week washout period. On days 1 and 7, profiles of augmentation index, central, and brachial BP were obtained over 180 min post-consumption in 4 fasted visits. A postprandial reduction in augmentation index was observed at 180 min on high-nitrate compared to low-nitrate intervention (-6.54 ± 9.7 % vs. -0.82 ± 8.0 %, p = 0.01) on Day 1, and from baseline on Day 7 (-6.93 ± 8.7 %, p < 0.001; high vs. low: -2.28 ± 12.5 %, p = 0.35), suggesting that the nitrate intervention is not associatedwith the development of tolerance for at least 7 days of continued supplementation. High vs. low-nitrate intervention also reduced central systolic (-3.39 ± 5.6 mmHg, p = 0.004) and diastolic BP (-2.60 ± 5.8 mmHg, p = 0.028) and brachial systolic BP (-3.48 ± 7.4 mmHg, p = 0.022) at 180 min following 7-day supplementation only. These findings suggest that dietary nitrate from spinach may contribute to beneficial hemodynamic effects of vegetable-rich diets and highlights the potential of developing a targeted dietary approach in the management of elevated BP.

Effect of coadministration of enriched Korean Red Ginseng (Panax ginseng) and American ginseng (Panax quinquefolius L) on cardiometabolic outcomes in type-2 diabetes: A randomized controlled trial

Elena Jovanovski,Lea Smircic-Duvnjak,Allison Komishon,Fei (Rodney) Au-Yeung,John L. Sievenpiper,Andreea Zurbau,Alexandra L. Jenkins,Mi-Kyung Sung,Robert Josse,Dandan Li,Vladimir Vuksan 고려인삼학회 2021 Journal of Ginseng Research Vol.45 No.5

Background: Diabetes mellitus and hypertension often occur together, amplifying cardiovascular disease (CVD) risk and emphasizing the need for a multitargeted treatment approach. American ginseng (AG) and Korean Red Ginseng (KRG) species could improve glycemic control via complementary mechanisms. Additionally, a KRG-inherent component, ginsenoside Rg3, may moderate blood pressure (BP). Our objective was to investigate the therapeutic potential of coadministration of Rg3-enriched Korean Red Ginseng (Rg3-KRG) and AG, added to standard of care therapy, in the management of hypertension and cardiometabolic risk factors in type-2 diabetes. Methods: Within a randomized controlled, parallel design of 80 participants with type-2 diabetes (HbA1c: 6.5e8%) and hypertension (systolic BP: 140e160 mmHg or treated), supplementation with either 2.25 g/day of combined Rg3-KRG þ AG or wheat-bran control was assessed over a 12-wk intervention period. The primary endpoint was ambulatory 24-h systolic BP. Additional endpoints included further hemodynamic assessment, glycemic control, plasma lipids and safety monitoring. Results: Combined ginseng intervention generated a mean ± SE decrease in primary endpoint of 24-h systolic BP (-3.98 ± 2.0 mmHg, p = 0.04). Additionally, there was a greater reduction in HbA1c (-0.35 ± 0.1% [e3.8 ± 1.1 mmol/mol], p = 0.02), and change in blood lipids: total cholesterol (-0.50 ± 0.2 mmol/l, p = 0.01), non-HDL-C (-0.54 ± 0.2 mmol/l, p = 0.01), triglycerides (-0.40 ± 0.2 mmol/l, p = 0.02) and LDL-C (-0.35 ± 0.2 mmol/l, p = 0.06) at 12 wks, relative to control. No adverse safety outcomes were observed. Conclusion: Coadministration of Rg3-KRG þ AG is an effective addon for improving BP along with attaining favorable cardiometabolic outcomes in individuals with type 2 diabetes. Ginseng derivatives may offer clinical utility when included in the polypharmacy and lifestyle treatment of diabetes. Clinical trial registration: Clinicaltrials.gov identifier, NCT01578837;

Carbohydrates and Endothelial Function: Is a Low-Carbohydrate Diet or a Low-Glycemic Index Diet Favourable for Vascular Health?

( Elena Jovanovski ),( Andreea Zurbau ),( Vladimir Vuksan ) 한국임상영양학회 2015 Clinical Nutrition Research Vol.4 No.2

Low-carbohydrate diets have become increasingly popular in both media and clinical research settings. Although they may improve some metabolic markers, their effects on arterial function remain unclear. Endothelial dysfunction is the well-established response to cardiovascular risk factors and a pivotal feature that precedes atherosclerotic diseases. It has been demonstrated that a high carbohydrate-induced hyperglycemia and subsequent oxidative stress acutely worsen the efficacy of the endothelial vasodilatory system. Thus, in theory, a carbohydrate restricted diet may preserve the integrity of the arterial system. This review attempts to provide insight on whether low-carbohydrate diets have a favorable or detrimental impact on vascular function, or it is perhaps the quality of carbohydrate that should direct dietary recommendations. Research to date suggests that diets low in carbohydrate amount may negatively impact vascular endothelial function. Conversely, it appears that maintaining recommended carbohydrate intake with utilization of low glycemic index foods generates a more favorable vascular profile. Understanding these relationships will aid in deciphering the diverging role of modulating quantity and quality of carbohydrates on cardiovascular risk.

Effects of Korean White Ginseng (Panax Ginseng C.A. Meyer) on Vascular and Glycemic Health in Type 2 Diabetes: Results of a Randomized, Double Blind, Placebo-controlled, Multiple-crossover, Acute Dose Escalation Trial

( Esra` Shishtar ),( Elena Jovanovski ),( Alexandra Jenkins ),( Vladimir Vuksan ) 한국임상영양학회 2014 Clinical Nutrition Research Vol.3 No.2

Korean red ginseng (steam treated Panax ginseng C.A. Meyer), among most prized traditional herbal remedies, has been clinicallyshown to improve cardiovascular disease (CVD) risk factors. Whether this holds true for the dried non-steamed variety, known as Korean white ginseng (KWG) is unclear. This study therefore, investigated the efficacy and safety of escalating doses of KWG on vascular and glycemic parameters in type 2 diabetes (T2DM). Using an acute, randomized, placebo-controlled, double- blind, crossover design, 25 participants with well-controlled T2DM (12-males: 13-females, age: 63 ± 9 years, A1c: 6.9 ± 0.7%, BMI: 29.3 ± 4.3 kg/m2) underwent five visits during which they received 1 g, 3 g, or 6 g KWG or 3 g wheat-bran control (twice) together with 50 g-glucose load. For the duration of 240 minutes, augmentation index (AI), and central blood pressure were measured at baseline and at 60 min-intervals, and ambulatory blood pressure was assessed at baseline and at 10 min-intervals. Additionally, capillary blood was collected at time zero and at 15, 30, 45, 60, 90, 120, and 180 minutes post-treatment. A symptoms questionnaire was used to assess safety and adverse events. Two-way ANOVA demonstrated a significant time-treatment interaction effect on AI (p = 0.01) with one-way ANOVA showing significant reductions in AI with 3 g KWG relative to control (p = 0.04). Compared to control, acute administration of KWG appeared to be safe, but did not affect any other postprandial, vascular or glycemic parameters. KWG might have a beneficial effect on AI, a cumulative indicator of arterial health. However, these results are preliminary and highlight the need for long-term investigation with a focus on its accountable components. Clinical Trial Registration: NCT01699074

Current Clinical Evidence for Korean Red Ginseng in Management of Diabetes and Vascular Disease: A Toronto's Ginseng Clinical Testing Program

Vuksan, Vladimir,Sievenpipper, John,Jovanovski, Elena,Jenkins, Alexandra L. The Korean Society of Ginseng 2010 Journal of Ginseng Research Vol.34 No.4

While ginseng is reported to have a wide array of applications, there is growing evidence for its indications in diabetes and vascular disease. A clear connection, however, has not been established between ginseng's composition, dose and its targeted efficacy in humans. We therefore developed and initiated the Korean Red Ginseng Clinical Testing Program for diabetes and vascular function which is an efficacy and safety-based clinical screening model for ginseng. The most efficacious sources, ginsenoside profiles, doses, and modes of administration were examined in sequential, acute, followed by long term, randomized-controlled trials to investigate the efficacy and safety profiles. This review discusses the current state of the clinical research of Korean red ginseng program conducted in Toronto, paving the way for the use of clinically selected ginseng and its ginsenoside fractions in the management of diabetes and vascular diseases.

Current Clinical Evidence for Korean Red Ginseng in Management of Diabetes and Vascular Disease: A Toronto’s Ginseng Clinical Testing Program

Vladimir Vuksan,John Sievenpipper,Elena Jovanovski,Alexandra L. Jenkins 고려인삼학회 2010 Journal of Ginseng Research Vol.34 No.4

While ginseng is reported to have a wide array of applications, there is growing evidence for its indications in diabetes and vascular disease. A clear connection, however, has not been established between ginseng’s composition, dose and its targeted efficacy in humans. We therefore developed and initiated the Korean Red Ginseng Clinical Testing Program for diabetes and vascular function which is an efficacy and safety-based clinical screening model for ginseng. The most efficacious sources, ginsenoside profiles, doses, and modes of administration were examined in sequential, acute, followed by long term, random- acute, followed by long term, random-andomized-controlled trials to investigate the efficacy and safety profiles. This review discusses the current state of the clinical re- This review discusses the current state of the clinical re- research of Korean red ginseng program conducted in Toronto, paving the way for the use of clinically selected ginseng and its ginsenoside fractions in the management of diabetes and vascular diseases.