Effects of pycnogenol on cardiometabolic health: A systematic review and meta-analysis of randomized controlled trials

The effect of chamomile consumption on glycemic markers in humans and animals: a systematic review and meta-analysis

Purpose

The use of natural and herbal products as alternative therapies, in conjunction with blood glucose-lowering medications, is on the rise for patients with diabetes. Our objective was to conduct a systematic review and comprehensive meta-analysis of both human and animal models to investigate the impact of chamomile consumption on glycemic control.

Methods

A systematic search was conducted on all published papers from January 1990 up to January 2022 via Scopus, PubMed/Medline, Google Scholar, and ISI Web of Science. Human and animal articles evaluating the effect of chamomile on serum glycemic markers were included. We used the random-effects model to establish the pooled effect size. The dose-dependent effect was also assessed.

Results

Overall, 4 clinical trials on human and 8 studies on animals met the inclusion criteria. With regard to RCTs, a favorable effect of chamomile consumption on serum fasting blood glucose (Standardized Mean Differences (SMD): -0.65, 95% CI: -1.00, -0.29, P < 0.001; I2 = 0%) and hemoglobin A1C (HbA1C) levels (SMD: -0.90, 95% CI: -1.39, -0.40, P < 0.001; I2 = 45.4%) was observed. Considering animal studies, consumption of chamomile extracts significantly reduced serum blood glucose (SMD: -4.37, 95% CI: -5.76, -2.98, P < 0.001; I2 = 61.2%). Moreover, each 100 mg/d increase in chamomile extract intervention resulted in a significantly declined blood glucose concentrations (MD: -54.35; 95% CI: -79.77, -28.93, P < 0.001; I2 = 94.8).

Conclusion

The current meta-analysis revealed that chamomile consumption could exert favorable effects on serum blood glucose and HbA1C. However, additional randomized controlled trials are needed to further confirm these findings.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01345-8.

Effect of a polyphenol-rich dietary supplement containing Pinus massoniana bark extract on blood pressure in healthy adults: A parallel, randomized placebo-controlled trial

OBJECTIVES

High blood pressure (BP) is a major risk factor for cardiovascular disease and prevalence rates continue to rise with ageing populations. Polypharmacy remains a burden among the ageing, thus alternative effective strategies are warranted. This study investigated the effects of a polyphenols rich dietary supplement containing Pinus massoniana bark extract (PMBE) for modulating BP in healthy Australian adults.

DESIGN

This study is a secondary analysis of data from a double-blinded, placebo-controlled clinical trial.

METHODS

Sixty-two healthy adults aged 55-75 years were randomized to receive 50 mL dietary supplement containing placebo (0 mg PMBE) or PMBE (1322 mg PMBE) daily for 12 weeks. Seated systolic BP (SBP) and diastolic (DBP) were measured at baseline, 6 weeks and 12 weeks. Effects of PMBE on modulating BP was also explored in this study stratified for SBP status (optimal v high) as well as by SBP medication status. Mixed effect regression modelling was employed involving fixed categorical effects for elapsed time, treatment assignment and their interaction as well as random subject-level intercept to account for within-subject correlations resulting from repeated measurements. Significant models were further examined by addition of covariates and power calculations were performed since this study was a secondary analysis.

RESULTS

SBP significantly reduced (-3.29 mmHg, p = 0.028) after PMBE at 12 weeks compared to baseline. SBP in individuals with normal-high SBP (>120 mmHg) in the PMBE group reduced by - 6.46 mmHg (p = 0.001) at 12 weeks compared to baseline. No significant changes were reported for individuals with optimal (≤120 mmHg) SBP nor did DBP significantly change in either study groups. In individuals with non-medicated normal-high SBP, SBP significantly reduced by - 7.49 mmHg (p = 0.001) and DBP by - 3.06 mmHg (p = 0.011) at 12 weeks compared to baseline after PMBE. Cross-group comparisons were not statistically different.

CONCLUSIONS

A polyphenol-rich dietary supplement derived from PMBE led to a clinically and statistically significant reduction in SBP in adults. Future studies to investigate the effects of PMBE-polyphenol supplementation on BP are warranted to confirm and explore optimal dose and impact on hypertension.

Antioxidant Effects of a Polyphenol-Rich Dietary Supplement Incorporating Pinus massoniana Bark Extract in Healthy Older Adults: A Two-Arm, Parallel Group, Randomized Placebo-Controlled Trial

Oxidative stress is a key physiological phenomenon underpinning the ageing process and plays a major developmental role in age-associated chronic diseases. This study investigated the antioxidant effects of a polyphenol-rich dietary supplement containing Pinus massoniana bark extract (PMBE) in healthy older adults. In a double-blinded, placebo-controlled clinical trial, participants were randomised (in a 1:1 ratio) to receive a 50 mL/day dietary supplement containing placebo (0 mg PMBE) or PMBE (1322 mg PMBE) for 12 weeks. The primary outcome was fasting plasma malondialdehyde (MDA) concentrations and secondary outcomes were plasma inflammatory markers. MDA concentrations significantly reduced following PMBE for 6 weeks (−1.19 nmol/mL, 95%CI −1.62, −0.75, p < 0.001) and 12 weeks (−1.35 nmol/mL, 95%CI −1.74, −0.96, p < 0.001) compared to baseline. MDA did not significantly change after the placebo. MDA levels at 6 and 12 weeks were significantly lower following PMBE compared to placebo (p < 0.001). At 12 weeks in the PMBE group, fibrinogen concentrations significantly reduced (−0.25 g/L, 95%CI −0.39, −0.11; p < 0.0001) and interleukin-6 significantly increased compared to placebo (0.30 pg/mL, 95%CI 0.02, 0.59; p < 0.05). PMBE in a polyphenol-rich dietary supplement reduced oxidative stress in healthy older adults. Further studies are warranted to investigate the antioxidant capacity of PMBE in conditions with heightened oxidative stress, such as osteoarthritis, hypertension, type 2 diabetes, or other lifestyle related diseases.

The Effect of Herbal Supplements on Blood Pressure: Systematic Review and Meta-Analysis

Herbal supplements rich in phenolic compounds are evidenced to have a protective effect against cardiovascular diseases. Therefore, they are suggested to be included in diets for people with hypertension (HT). HT is a global health problem and is estimated to affect billions of people until the end of 2025. For this reason, every possible and effective solution preventing HT should be considered. The aim was to perform an updated meta-analysis and review of recently published studies to evaluate the effect of selected herbal supplements on blood pressure reduction. We searched the PubMed database with specified selection criteria, analysing the RCT studies from 2011 to 2021. A total of 31 studies were included in the analysis, and the meta-analysis was conducted on the data from 16 of them. The general effect size of all the supplements via placebo was d = 1.45, p < 0.05 for systolic blood pressure (SBP) and d = 0.31, p < 0.05 for diastolic blood pressure (DBP). The meta-analysis and review of the literature demonstrated that herbal supplements, such as resveratrol, cherry juice, beetroot juice, bergamot extracts, barberry, and pycnogenol, can be effective in blood pressure reduction and cardiovascular prevention, but attention should be paid to their appropriate dosage due to the possibility of side effects from the digestive system.

The role of Pycnogenol in the control of inflammation and oxidative stress in chronic diseases: Molecular aspects

The prevalence of chronic diseases has increased significantly with the rising trend of sedentary lifestyles, reduced physical activity, and dietary modifications in recent decades. Inflammation and oxidative stress play a key role in the pathophysiology of several chronic diseases, such as type II diabetes, cardiovascular diseases, and hepatic conditions. Therefore, reducing inflammation and oxidative stress may be beneficial in the prevention and treatment of various chronic disorders. Since chronic diseases are not completely curable, various methods have been proposed for their control. Complementary therapies and the use of natural antioxidant and antiinflammatory compounds are among these novel approaches. Pycnogenol (PYC) is a natural compound that could control inflammation and oxidative stress. Furthermore, some previous studies have shown that PYC could effectively reduce inflammation through signaling the downstream of insulin receptors, inhibiting the phosphorylation of the serine residues of insulin receptor substrate-1, reducing pro-inflammatory cytokines and oxidative stress indices through the stimulation of antioxidant pathways, increasing free radical scavenging activities, preventing lipid peroxidation, and protecting the erythrocytes in glucose-6-phosphate dehydrogenase-deficient individuals, although these effects have not been fully proved. The present study aimed to comprehensively review the evidence concerning the positive physiological and pharmacological properties of PYC, with an emphasis on the therapeutic potential of this natural component for enhancing human health.

The effect of French maritime pine bark extract supplementation on inflammation, nutritional and clinical status in critically ill patients with traumatic brain injury: A randomized controlled trial

Inflammation plays an important role in the pathophysiology of traumatic brain injury (TBI). Based on the anti-inflammatory properties of French maritime pine bark extract and the neuroprotective effects, we aimed to evaluate the effects of its supplementation on TBI. Sixty-seven TBI patients admitted to the intensive care units (ICUs) were enrolled. After stabilizing the hemodynamic status, the intervention group received 150 mg of French maritime pine bark extract supplementation (Oligopin) with enteral nutrition for 10 days. The control group received a placebo. Inflammatory status and oxidative stress markers were measured three times. Also, clinical and nutritional statuses were assessed. Supplementation, significantly decreased IL-6 (β = -53.43 pg/ml, 95% confidence interval [CI] = -91.74, -15.13, p = .006), IL-1β (β = -111.66 pg/ml, 95% CI = -183.79, -39.5402, p = .002) and C-reactive protein (β = -19.99 mg/L, 95% CI = -27.23, -12.76, p ˃ .001) in the intervention group compared to control group after 10 days. Clinical scores including acute physiology and chronic health evaluation II and sequential organ failure assessment were reduced (β = -3.72, 95% CI = -5.96, -1.49, p = .001and β = -2.07, 95% CI = -3.23, -0.90, p < .001, respectively), and Nutric score was reduced compared to control group (β = -.60, 95% CI = -1.08, -0.12, p = .01). The survival rate was higher by 15% in the intervention group compared to control group. Oligopin supplementation in TBI patients in ICU reduced inflammation and improved the clinical status and malnutrition score and thereby reducing the mortality rate.

The Effect of Oligopin Supplementation on Hormonal and Metabolic Profiles in the Polycystic Ovary Syndrome: A Randomized Controlled Trial

Background

A double blind clinical trial was performed to evaluate whether the polycystic ovary syndrome (PCOS)-specific serum markers and metabolic parameters would change in the women with PCOS during the three-month administration of oligopin.

Methods

In this double-blind multicenter trial, we randomly assigned 80 PCOS women, based on a 1:1 ratio, to receive oligopin (n= 40) or maltodextrin as placebo (n = 40) for up to 3 months. As PCOS-specific outcomes, we investigated the changes in testosterone, sex hormone binding globulin (SHBG), free androgen index (FAI), dehydroepiandrosterone (DHEA), follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Secondary end points were metabolic (fasting glycaemia, hemoglobin A1c (HbA1c), lipids, insulin resistance (HOMA-IR)), anthropometrics parameters and blood pressure from the baseline to the end of treatment. We investigated serum transaminase, alkaline phosphatase (ALP), creatinine (Cr) and blood urea nitrogen (BUN) levels as hepatic and kidney outcomes, respectively.

Results

The first participant was enrolled on April 18, 2018, and the last study visit took place on May 14, 2019. PCOS-specific serum parameters did not change during the three-month administration of oligopin (p > 0.05), except for a small increase in the FSH levels (p=0.03). Oligopin neither changed the metabolic profile nor the anthropometric parameters or blood pressure. ALP levels was significantly increased in placebo group, as compared with oligopin (p=0.01).

Conclusion

Oligopin supplementation does not seem to be exerting a beneficial effect on both hormonal and metabolic parameters in the women with PCOS.

Clinical Trial Registration

www.irct.ir, identifier IRCT20140406017139N3.

Evaluation of the effects of pycnogenol (French maritime pine bark extract) supplementation on inflammatory biomarkers and nutritional and clinical status in traumatic brain injury patients in an intensive care unit: A randomized clinical trial protocol

Background

Traumatic brain injury (TBI) is one of the major health and socioeconomic problems in the world. Immune-enhancing enteral formula has been proven to significantly reduce infection rate in TBI patients. One of the ingredients that can be used in immunonutrition formulas to reduce inflammation and oxidative stress is pycnogenol.

Objective

The objective of this work is to survey the effect of pycnogenol on the clinical, nutritional, and inflammatory status of TBI patients.

Methods

This is a double-blind, randomized controlled trial. Block randomization will be used. An intervention group will receive pycnogenol supplementation of 150 mg for 10 days and a control group will receive a placebo for the same duration. Inflammatory status (IL-6, IL- 1β, C-reactive protein) and oxidative stress status (malondialdehyde, total antioxidant capacity), at the baseline, at the 5th day, and at the end of the study (10th day) will be measured. Clinical and nutritional status will be assessed three times during the intervention. The Sequential Organ Failure Assessment (SOFA) questionnaire for assessment of organ failure will be filled out every other day. The mortality rate will be calculated within 28 days of the start of the intervention. Weight, body mass index, and body composition will be measured. All analyses will be conducted by an initially assigned study arm in an intention-to-treat analysis.

Discussion

We expect that supplementation of 150 mg pycnogenol for 10 days will improve clinical and nutritional status and reduce the inflammation and oxidative stress of the TBI patients.

Trial registration

This trial is registered at clinicaltrials.gov (ref: NCT03777683) at 12/13/2018.