Pycnogenol® supplementation improves health risk factors in subjects with metabolic syndrome

Does supplementation with pine bark extract improve cardiometabolic risk factors? A systematic review and meta-analysis

BACKGROUND

Supplementation with pine bark extract (PBE) may improve risk factors associated with cardiometabolic syndrome (CMS). The effects of PBE supplementation on cardiometabolic risk factors were evaluated in this systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

A comprehensive search of various databases was performed to identify relevant RCTs published up to September 2024. A random-effects model was employed for the meta-analysis, which included 27 RCTs with 1,685 participants.

RESULTS

The findings indicated that PBE supplementation significantly reduced systolic blood pressure (SBP) (weighted mean difference (WMD): -2.26 mmHg, 95% confidence interval (CI): -3.73, -0.79; P = 0.003), diastolic blood pressure (DBP) (WMD: -2.62 mmHg, 95% CI: -3.71, -1.53; P < 0.001), fasting blood sugar (FBS) (WMD: -6.25 mg/dL, 95% CI: -9.97, -2.53; P = 0.001), hemoglobin A1c (HbA1c) (WMD: -0.32%, 95% CI: -0.54, -0.11; P = 0.003), body weight (WMD: -1.37 kg, 95% CI: -1.86, -0.88; P < 0.001), and low-density lipoprotein (LDL) cholesterol (WMD: -5.07 mg/dL, 95% CI: -9.21, -0.94; P = 0.016) in the PBE-treated group compared to their untreated counterparts. However, no significant impact of PBE was observed on waist-to-hip ratio (WHR), body mass index (BMI), waist circumference (WC), or serum levels of insulin, high-density lipoprotein (HDL) cholesterol, triglycerides (TG), and total cholesterol (TC).

CONCLUSIONS

Supplementation with PBE may ameliorate specific cardiometabolic risk factors, as indicated by reductions in body weight, DBP, SBP, FBS, LDL, and HbA1c levels. This approach can be regarded as an adjunct therapeutic strategy for CMS management. Further high-quality trials with larger sample sizes and longer durations are required to validate these findings.

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.

Anti-fibrotic effect of pycnogenol® in a polyhexamethylene guanidine-treated mouse model

Pulmonary fibrosis (PF) is a respiratory disease that causes serious respiratory problems. The effects of French marine pine bark extract (Pycnogenol®), with antioxidant and anti-inflammatory properties, were investigated on lung fibrosis in polyhexamethylene guanidine (PHMG)-treated mice. Mice were separated into four groups (n = 6): vehicle control (VC, saline 50 μl); PHMG (1.1 mg/kg); PHMG + Pycnogenol® (0.3 mg/kg/day); and PHMG + Pycnogenol® (1 mg/kg/day). PF was induced via intratracheal instillation of PHMG. Treatment with PHMG decreased body weight and increased lung weight, both of which were improved by treatment with PHMG + Pycnogenol® (1 mg/kg). Enzyme-linked immunosorbent assay, western blotting, and PCR revealed that Pycnogenol® attenuated PHMG-induced increase in inflammatory cytokines and fibrosis-related factors in a dose-dependent manner. Finally, histopathological analysis revealed reduced inflammation/fibrosis in the PHMG + Pycnogenol® (1 mg/kg) group. Collectively, the results indicate that Pycnogenol® can be used to treat PF as it hinders fibrosis progression by inhibiting inflammatory responses in the lungs of PHMG-treated mice.

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.

Effect of French maritime pine bark extract supplementation on metabolic status and serum vascular cell adhesion molecule-1 levels in patients with type 2 diabetes and microalbuminuria

OBJECTIVES

This study investigated the effect of French maritime pine bark extract (PBE) supplementation on metabolic parameters, vascular cell adhesion molecule 1 (VCAM-1), urinary albumin-to-creatinine ratio (UACR), and anthropometric indexes in patients with type 2 diabetes (T2DM) and microalbuminuria.

DESIGN

This randomized, double-blind, placebo-controlled clinical trial was conducted on 46 patients with T2DM and the evidence of microalbuminuria aged 30-65 years.

SETTING

Patients were recruited from the endocrinology clinic of Sina hospital (Tabriz, Iran) from March 2018 to April 2019.

INTERVENTIONS

The subjects were randomly assigned to receive two capsules/day each containing 50mg of PBE or placebo for eight weeks.

MAIN OUTCOME MEASURES

Glycemic parameters, serum VCAM-1 and lipid profile, UACR, and anthropometric indexes were measured for all patients at baseline and the end of the study.

RESULTS

PBE supplementation significantly reduced glycosylated hemoglobin, VCAM-1, total cholesterol, UACR, waist circumference, and waist-to-height ratio compared to the placebo group at the end of the study (all P < 0.05). Changes in fasting blood glucose, insulin, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were not significant between the two groups (all P > 0.05).

CONCLUSIONS

The study findings demonstrated some favorable effects of PBE supplementation on glycemic control, serum VCAM-1 and total cholesterol levels, and microalbuminuria, as well as abdominal obesity in patients with T2DM.

Complementary effects of pine bark extract supplementation on inattention, impulsivity, and antioxidative status in children with attention-deficit hyperactivity disorder: A double-blinded randomized placebo-controlled cross-over study

The purpose of this study was to investigate the complementary effects of polyphenolic compounds from pine bark extract (PE) as a strong antioxidative substrate on the symptoms of inattention and impulsivity in children with attention-deficit hyperactivity disorder (ADHD). This was a randomized, double-blind, crossover, placebo-controlled study that included two experimental units (4 weeks with PE supplementation and 4 weeks with placebo supplementation) separated by a 2-week washout period. ADHD participants were supplemented with 25 mg or 50 mg PE. We recruited 20 participants (17 boys and 3 girls) with a mean age of 10.0 ± 2.1 years. PE supplementation caused a significant reduction in the inattention and hyperactivity-impulsivity items of SNAP-IV. During the period of PE supplementation, the item of commissions in the Continuous Performance Test III (CPT III) significantly decreased, which was used to evaluate the symptoms of inattention and impulsivity. In addition, the erythrocytic reduced glutathione/oxidized glutathione ratio significantly increased, and the plasma TBARs level significantly decreased after 4 weeks of PE supplementation. However, there was no significant correlation between CPT III (commission) and antioxidative status indictors. PE supplementation may have potential effects of ameliorating inattention and impulsivity, and elevating the antioxidative status in children with ADHD.

Pine bark (Pinus spp.) extract for treating chronic disorders

BACKGROUND

Pine bark (Pinus spp.) extract is rich in bioflavonoids, predominantly proanthocyanidins, which are antioxidants. Commercially-available extract supplements are marketed for preventing or treating various chronic conditions associated with oxidative stress. This is an update of a previously published review.

OBJECTIVES

To assess the efficacy and safety of pine bark extract supplements for treating chronic disorders.

SEARCH METHODS

We searched three databases and three trial registries; latest search: 30 September 2019. We contacted the manufacturers of pine bark extracts to identify additional studies and hand-searched bibliographies of included studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating pine bark extract supplements in adults or children with any chronic disorder.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, extracted data and assessed risk of bias. Where possible, we pooled data in meta-analyses. We used GRADE to evaluate the certainty of evidence. Primary outcomes were participant- and investigator-reported clinical outcomes directly related to each disorder and all-cause mortality. We also assessed adverse events and biomarkers of oxidative stress.

MAIN RESULTS

This review included 27 RCTs (22 parallel and five cross-over designs; 1641 participants) evaluating pine bark extract supplements across 10 chronic disorders: asthma (two studies; 86 participants); attention deficit hyperactivity disorder (ADHD) (one study; 61 participants), cardiovascular disease (CVD) and risk factors (seven studies; 338 participants), chronic venous insufficiency (CVI) (two studies; 60 participants), diabetes mellitus (DM) (six studies; 339 participants), erectile dysfunction (three studies; 277 participants), female sexual dysfunction (one study; 83 participants), osteoarthritis (three studies; 293 participants), osteopenia (one study; 44 participants) and traumatic brain injury (one study; 60 participants). Two studies exclusively recruited children; the remainder recruited adults. Trials lasted between four weeks and six months. Placebo was the control in 24 studies. Overall risk of bias was low for four, high for one and unclear for 22 studies. In adults with asthma, we do not know whether pine bark extract increases change in forced expiratory volume in one second (FEV1) % predicted/forced vital capacity (FVC) (mean difference (MD) 7.70, 95% confidence interval (CI) 3.19 to 12.21; one study; 44 participants; very low-certainty evidence), increases change in FEV1 % predicted (MD 7.00, 95% CI 0.10 to 13.90; one study; 44 participants; very low-certainty evidence), improves asthma symptoms (risk ratio (RR) 1.85, 95% CI 1.32 to 2.58; one study; 60 participants; very low-certainty evidence) or increases the number of people able to stop using albuterol inhalers (RR 6.00, 95% CI 1.97 to 18.25; one study; 60 participants; very low-certainty evidence). In children with ADHD, we do not know whether pine bark extract decreases inattention and hyperactivity assessed by parent- and teacher-rating scales (narrative synthesis; one study; 57 participants; very low-certainty evidence) or increases the change in visual-motoric coordination and concentration (MD 3.37, 95% CI 2.41 to 4.33; one study; 57 participants; very low-certainty evidence). In participants with CVD, we do not know whether pine bark extract decreases diastolic blood pressure (MD -3.00 mm Hg, 95% CI -4.51 to -1.49; one study; 61 participants; very low-certainty evidence); increases HDL cholesterol (MD 0.05 mmol/L, 95% CI -0.01 to 0.11; one study; 61 participants; very low-certainty evidence) or decreases LDL cholesterol (MD -0.03 mmol/L, 95% CI -0.05 to 0.00; one study; 61 participants; very low-certainty evidence). In participants with CVI, we do not know whether pine bark extract decreases pain scores (MD -0.59, 95% CI -1.02 to -0.16; one study; 40 participants; very low-certainty evidence), increases the disappearance of pain (RR 25.0, 95% CI 1.58 to 395.48; one study; 40 participants; very low-certainty evidence) or increases physician-judged treatment efficacy (RR 4.75, 95% CI 1.97 to 11.48; 1 study; 40 participants; very low-certainty evidence). In type 2 DM, we do not know whether pine bark extract leads to a greater reduction in fasting blood glucose (MD 1.0 mmol/L, 95% CI 0.91 to 1.09; one study; 48 participants;very low-certainty evidence) or decreases HbA1c (MD -0.90 %, 95% CI -1.78 to -0.02; 1 study; 48 participants; very low-certainty evidence). In a mixed group of participants with type 1 and type 2 DM we do not know whether pine bark extract decreases HbA1c (MD -0.20 %, 95% CI -1.83 to 1.43; one study; 67 participants; very low-certainty evidence). In men with erectile dysfunction, we do not know whether pine bark extract supplements increase International Index of Erectile Function-5 scores (not pooled; two studies; 147 participants; very low-certainty evidence). In women with sexual dysfunction, we do not know whether pine bark extract increases satisfaction as measured by the Female Sexual Function Index (MD 5.10, 95% CI 3.49 to 6.71; one study; 75 participants; very low-certainty evidence) or leads to a greater reduction of pain scores (MD 4.30, 95% CI 2.69 to 5.91; one study; 75 participants; very low-certainty evidence). In adults with osteoarthritis of the knee, we do not know whether pine bark extract decreases composite Western Ontario and McMaster Universities Osteoarthritis Index scores (MD -730.00, 95% CI -1011.95 to -448.05; one study; 37 participants; very low-certainty evidence) or the use of non-steroidal anti-inflammatory medication (MD -18.30, 95% CI -25.14 to -11.46; one study; 35 participants; very low-certainty evidence). We do not know whether pine bark extract increases bone alkaline phosphatase in post-menopausal women with osteopenia (MD 1.16 ug/L, 95% CI -2.37 to 4.69; one study; 40 participants; very low-certainty evidence). In individuals with traumatic brain injury, we do not know whether pine bark extract decreases cognitive failure scores (MD -2.24, 95% CI -11.17 to 6.69; one study; 56 participants; very low-certainty evidence) or post-concussion symptoms (MD -0.76, 95% CI -5.39 to 3.87; one study; 56 participants; very low-certainty evidence). For most comparisons, studies did not report outcomes of hospital admissions or serious adverse events.

AUTHORS' CONCLUSIONS

Small sample sizes, limited numbers of RCTs per condition, variation in outcome measures, and poor reporting of the included RCTs mean no definitive conclusions regarding the efficacy or safety of pine bark extract supplements are possible.

A Double-Blind Randomized Placebo-Controlled Study Assessing the Safety, Tolerability and Efficacy of a Herbal Medicine Containing Pycnogenol Combined with Papain and Aloe vera in the Prevention and Management of Pre-Diabetes

Background: Herbal medicines present attractive options to patients with chronic diseases. Undertaking clinical studies with patients presenting with symptomless pre-T2D can lead to significant limitations. Methods: A 12-week randomized double-blind placebo-controlled clinical study was conducted that investigated the safety and efficacy of an herbal formulation administered orally for the treatment of pre-type 2 diabetes (pre-T2D). Results: A numerically greater proportion of subjects in the interventional arm had impaired fasting glucose (IFG) at week 12 compared to the control arm (71.0% vs. 69.0%, p = 0.75). Fewer participants had impaired glucose tolerance (IGT) at 12 weeks in the intervention arm compared to the control arm (unadjusted 58.3% vs. 66.7%, p = 0.65; adjusting for baseline IGT, p = 0.266). In a subgroup analysis, subjects with a baseline fasting plasma glucose (FPG) level in the range of 6.1-6.9 mmol/L demonstrated a non-significant lower proportion of IFG at week 12 in the intervention arm compared to the control arm (60.0% vs. 41.7% p = 0.343). Total blood cholesterol and triglyceride levels remained unchanged from baseline to week 12 in both treatment groups. Conclusions: This study suggests that a polyherbal medicine was not effective for reducing the metabolic markers associated with pre-T2D over a 12-week period. Therefore, larger studies with well-defined endpoints and of longer duration are warranted.

Effect of Pycnogenol on Blood Pressure: Findings From a PRISMA Compliant Systematic Review and Meta-Analysis of Randomized, Double-Blind, Placebo-Controlled, Clinical Studies

Results of previous clinical trials evaluating the effect of pycnogenol supplementation on blood pressure (BP) are controversial. Therefore, we aimed to assess the impact of pycnogenol on BP through a systematic review of literature and meta-analysis of available randomized, double-blind, placebo-controlled clinical studies (randomized clinical trials [RCTs]). Literature search included SCOPUS, PubMed-Medline, ISI Web of Science, and Google Scholar databases up to January 10, 2019 to identify RCTs investigating the impact of pycnogenol on BP. Two investigators independently extracted data on study characteristics, methods, and outcomes. This systematic review and meta-analysis is registered in International Prospective Register of Systematic Reviews (PROSPERO) under number CRD42018112172. Overall, the impact of pycnogenol on BP was reported in 7 trials involving 626 participants. Meta-analysis did not suggest any significant improvement in systolic BP (weighted mean difference [WMD]: −0.028 mm Hg; 95% confidence interval [CI]: −0.182 to 0.127; P = .726; I2= 46%), diastolic BP (WMD: −0.144 mm Hg; 95% CI: −0.299 to 0.010; P = .067; I2= 0%), mean arterial pressure (WMD: −0.091 mm Hg; 95% CI: −0.246 to 0.063; P = .246; I2= 0%), and pulse pressure (WMD: −0.003 mm Hg; 95% CI: −0.151 to 0.158; P = .966; I2= 0%) following pycnogenol treatment. Results persisted in the leave-one-out sensitivity analysis. Therefore, the present meta-analysis does not suggest any significant effect of pycnogenol on BP.

Baicalein attenuates OVA-induced allergic airway inflammation through the inhibition of the NF-κB signaling pathway

Asthma is a type of chronic lung inflammation with restrictions in effective therapy. NF-κB pathway activation has been suggested to play an important role in the pathogenesis of asthma. Baicalein, one of the major active flavonoids found in Scutellaria baicalensis, exhibits potent anti-inflammatory properties by inhibiting NF-κB activity. Herein, we report that Baicalein significantly reduces OVA-induced airway hyperresponsiveness (AHR), airway inflammation, serum IgE levels, mucus production, and collagen deposition around the airway. Additionally, western blot analysis and immunofluorescence assay showed that Baicalein attenuates the activation of NF-κB, which was mainly reflected by IκBα phosphorylation and degradation, p65 nuclear translocation and downstream iNOS expression. Furthermore, in human epithelial cells, Baicalein blocked TNF-α-induced NF-κB activation. Our study provides evidence that Baicalein administration alleviates the pathological changes in asthma through inactivating the NF-κB/iNOS pathway. Baicalein might be a promising potential therapy agent for patients with allergic asthma in the future.

Effect of pycnogenol supplementation on blood pressure: A systematic review and meta-analysis of clinical trials

Several studies investigated the impact of pycnogenol on blood pressure. Nevertheless, the results are inconclusive. The aim of the present systematic review and meta-analysis was to clarify the effect of pycnogenol supplementation on blood pressure. PubMed, Scopus, Web of Science, and Google Scholar were systematically searched until March 2018 to find clinical trials, which examined the effect of pycnogenol supplementation on systolic and diastolic blood pressure in adults. A subgroup analysis was applied to find out potential sources of interstudy heterogeneity. A total of 12 clinical trials (922 participants) were included in the meta-analysis. Pooled analysis suggested that pycnogenol supplementation can reduced systolic blood pressure (SBP) of (-3.22 mmHg; 95% CI [-5.52, -0.92]) and diastolic blood pressure (DBP; -1.91 mmHg; 95% CI [-3.64, -0.18]). Effect of pycnogenol on SBP was more pronounce in subgroup in which pycnogenol was administered along with other treatments. A significant effect of pycnogenol on DBP in studies with >12-week duration, whereas this favorable effect was not observed in subgroup with ≤12-week supplementation. The present systematic review and meta-analysis suggest that pycnogenol had a favorable effect on SBP and DBP. Further, high quality randomized clinical trials are needed to confirm this result.

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

AIM

Clinical trials on the effect of pycnogenol supplementation on cardiometabolic health have been controversial. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the potential effect of pycnogenol supplementation on cardiometabolic profile.

METHODS

PubMed, Scopus, and ISI Web of Science databases were searched until October 2018. RCTs that evaluated the effects of pycnogenol on cardiometabolic parameters were included. DerSimonian and Laird random-effect models were used to compute the weighted mean differences (WMDs) and 95% confidence intervals (CIs).

RESULTS

Twenty-four RCTs including 1594 participants were included in the meta-analysis. Pycnogenol significantly reduced fasting blood glucose (WMD: -5.86 mg/dl; 95% CI: -9.56, -2.15), glycated hemoglobin (WMD = -0.29%, 95%CI: -0.56, -0.01), systolic blood pressure (WMD: -2.54 mmhg; 95% CI: -4.08, -0.99), diastolic blood pressure (WMD: -1.76 mmhg; 95% CI: -3.12, -0.41), body mass index (WMD: -0.47 kg/m²; 95% CI: -0.90, -0.03), LDL cholesterol (WMD: -7.12 mg/dl; 95% CI: -13.66, -0.58) and increased HDL cholesterol (WMD: 3.27 mg/dl; 95% CI: 0.87, 5.66).

CONCLUSION

This meta-analysis suggests that pycnogenol may have a role in preventing cardiometabolic disease. However, further well-designed RCTs are recommended to evaluate its long-term effects and explore the optimal duration of use and dosage.

Pleiotropic Effects of French Maritime Pine Bark Extract to Promote Healthy Aging

Extension of the healthy life span is of primary importance for the aging society. Among exercise, healthy nutrition, and mental training, food supplements are widely used as preventive measures to postpone the diverse symptoms of aging. The extract from the bark of the French maritime pine, Pycnogenol, rich on flavonoids, has anti-inflammatory and antioxidative property, proven in in vivo studies. The extract reduces oxidative stress and improves endothelial health. Its antithrombotic properties are based on inhibition of platelet aggregation. In double-blind, placebo-controlled clinical studies, Pycnogenol shows diverse positive effects. With respect to cardiovascular symptoms, the extract has an antihypertensive effect, slows down the progression of atherosclerosis, and prevents venous thrombosis. As reported in studies in China and the United States, type 2 diabetes and diabetic retinopathy is improved with Pycnogenol. The extract restores mobility of seniors in case of patients suffering from osteoarthritis, Pycnogenol reduces pain and stiffness and use of analgesics. Furthermore, cognitive functions of elderly people, especially spatial memory, are significantly ameliorated. Climacteric symptoms are significantly alleviated by the pine bark extract. Urinary symptoms of benign prostatic hyperplasia are reduced by Pycnogenol. In combination with L-arginine, Pycnogenol restores erectile function in men with erectile dysfunction. The sum of these positive effects on relevant symptoms of aging suggests using Pycnogenol for a more extended period of healthy aging.

The impact of pycnogenol supplementation on plasma lipids in humans: A systematic review and meta-analysis of clinical trials

The effects of pycnogenol on plasma lipids are controversial. A systematic review and meta-analysis of clinical trials were conducted to obtain a conclusive result in humans. PubMed, Scopus, and Google Scholar were systematically searched until March 2018, to explore the clinical trials that examined the effect of pycnogenol supplementation on lipid parameters among adult human. Methodological quality of the eligible studies was evaluated using the Cochrane Collaboration's tool. To estimate the effect size, changes in blood lipids were implemented. Results were pooled using a random effects model. Potential sources of heterogeneity were explored by subgroup analysis. A systematic review and meta-analysis of 14 clinical trials with 1,065 participants suggested a significant increase in plasma concentration of high density lipoprotein cholesterol (HDL-C; 3.27 mg/dL; 95% CI [0.19, 6.36]; p = 0.038). In contrast, plasma levels of total cholesterol (TC; -4.45 mg/dL, 95% CI [-11.24, 2.34]; p = 0.199), triacylglycerol (TAG; -3.64 mg/dL; 95% CI [-17.89, 10.61]; p = 0.616), and low density lipoprotein cholesterol (LDL-C; -3.61 mg/dl; 95% CI [-8.76, 1.55]; p = 0.171) were not altered. Adjustment for confounding variables was poor in included studies. Also, these studies did not assess dietary lipid intake. The results indicate that pycnogenol supplementation improves levels of HDL-C; however, the changes in TC, TAG, and LDL-C were not clinically relevant. Since there are few phytochemicals that have a significant increasing effect on HDL-C levels, pycnogenol may have important role in prevention of cardiovascular diseases.

Pycnogenol protects against diet-induced hepatic steatosis in apolipoprotein-E-deficient mice

Pycnogenol^R (PYC), a combination of active flavonoids derived from French maritime pine bark, is a natural antioxidant that has various pharmacological activities. Here, we investigated the beneficial effect of PYC on diet-induced hepatic steatosis. Apolipoprotein E (ApoE)-deficient male mice were administered PYC at oral doses of 30 or 100 mg·kg^-1·day^-1 for 2 wk in advance and were then fed a high-cholesterol and -fat diet (HCD) for 8 wk. Biochemical, immunohistochemical, and gene expression analyses were conducted to explore the effect of PYC on lipid metabolism in ApoE-deficient mice on a HCD. Short-term treatment with HCD in ApoE-deficient mice induced hepatic injuries, such as lipid metabolism disorder and hepatic histopathological changes. We found that PYC reduced body weight and the increase of serum lipids that had been caused by HCD. Supplementation of PYC significantly reduced lipid deposition in the liver, as shown by the lowered hepatic lipid content and histopathological lesions. We subsequently detected genes related to lipid metabolism and inflammatory cytokines. The study showed that PYC markedly suppressed the expression of genes related to hepatic lipogenesis, fatty acid uptake, and lipid storage while increasing the lipolytic gene, which thus reduced hepatic lipid content. Furthermore, PYC mainly reduced the expression of inflammatory cytokines and the infiltration of inflammatory cells, which were resistant to the development of hepatic steatosis. These results demonstrate that PYC protects against the occurrence and development of hepatic steatosis and may provide a new prophylactic approach for nonalcoholic fatty liver disease (NAFLD).

The Effect of Pycnogenol Supplementation on Plasma C-Reactive Protein Concentration: a Systematic Review and Meta-Analysis

Pycnogenol is a standardized extract from the bark of the French maritime pine. The aim of the present systematic review and meta-analysis was to clarify the effect of Pycnogenol supplementation on C-reactive protein (CRP) concentration. To identify eligible studies in order to find clinical trials which examined the effect of Pycnogenol supplementation on the level of CRP in adult participants, PubMed, Scopus, and Google Scholar were systematically searched until December 2017. Mean of CRP was collected to estimate the effect size of the supplementation. Potential sources of heterogeneity were explored by subgroup analysis. Five trials including 324 participants were included in this meta-analysis. Pooled effect size showed significant effect of Pycnogenol supplementation on CRP (−1.22 mg/dL, 95% confidence interval, −2.43, −0.003; I² = 99%, p_{heterogeneity} < 0.001). When the meta-analysis was subgrouped by dose of Pycnogenol, heterogeneity was attenuated in > 150 mg/d category (I² = 0.0%, p = 0.42). There was significant difference between-subgroup heterogeneity (p < 0.001). Furthermore, no evidence of publication bias for CRP (p = 0.27, Begg's test and p = 0.62, Egger's test) was seen. Present systematic review and meta-analysis suggested Pycnogenol consumption can decrease the level of CRP and have anti-inflammatory effect. So, Pycnogenol as an anti-inflammatory agent might be a priority in interventions. Further studies with large-scale and better design are needed to confirm this result.

Pycnogenol® Induces Browning of White Adipose Tissue through the PKA Signaling Pathway in Apolipoprotein E-Deficient Mice

Beige adipocytes in white adipose tissue (WAT) have received considerable recognition because of their potential protective effect against obesity. Pycnogenol (PYC), extracted from French maritime pine bark, has anti-inflammatory and antioxidant properties and can improve lipid profiles. However, the effect of PYC on obesity has never been explored. In this study, we investigated the effects of PYC on obesity and WAT browning in apolipoprotein E- (ApoE-) deficient mice. The results showed that PYC treatment clearly reversed body weight and the mass of eWAT gain resulting from a high-cholesterol and high-fat diet (HCD), but no difference in food intake. The morphology results showed that the size of the adipocytes in the PYC-treated mice was obviously smaller than that in the HCD-fed mice. Next, we found that PYC upregulated the expression of genes related to lipolysis (ATGL and HSL), while it decreased the mRNA level of PLIN1. PYC significantly increased the expression of UCP1 and other genes related to beige adipogenesis. Additionally, PYC increased the expression of proteins related to the protein kinase A (PKA) signaling pathway. The findings suggested that PYC decreased obesity by promoting lipolysis and WAT browning. Thus, PYC may be a novel therapeutic target for obesity.

Effects of low molecular weight procyanidin rich extract from french maritime pine bark on cardiovascular disease risk factors in stage-1 hypertensive subjects: Randomized, double-blind, crossover, placebo-controlled intervention trial

BACKGROUND

Oligopin^ۚ (OP) is a quantified extract from French Maritime Pine bark (FMPB) with low molecular weight procyanidins. The cardioprotective effects of OP need to be tested in human clinical intervention trials with an appropriate design.

PURPOSE

The aim of the present study was to assess the effect of subchronic consumption of OP on cardiovascular disease risk factors such as lipid profile, systolic blood pressure (BP) and oxidized-Low Density Lipoprotein (ox-LDL) in stage-1-hypertensive subjects.

METHODS

Between February 14 and May 31, 2014, eligible subjects were recruited from the outpatient clinics of Hospital Universitari Sant Joan (Reus, Spain). A total of 24 participants (mean age ± DS; 57.36 ± 11.25; 17 men) with stage-1-hypertension who were not receiving BP-lowering medication and LDL cholesterol < 4.88 mmol/l were randomized in a double-blind, placebo-controlled, crossover study. The subjects received 2 capsules/day with 75 mg of OP or placebo for 5-weeks.

RESULTS

At 5-weeks, compared to the placebo, OP raised High Density Lipoprotein-cholesterol (HDL-c) by 14.06% (p = 0.012) and apolipoprotein A-1 by 8.12% (p = 0.038) and reduced the ratio of apolipoprotein B-100/A-1 by 10.26% (p = 0.046). Moreover, at 5-weeks, compared to the baseline, OP reduced the systolic BP by 6.36 mmHg (p = 0.014), and decreased ox-LDL concentrations by 31.72 U/l (p = 0.015).

CONCLUSION

At 5-weeks, the consumption of 150 mg/day of OP improve lipid cardiovascular profile and represents one of the scarce ways to increase HDL-c in stage-1-hypertensive subjects.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02063477.

Pycnogenol® in Metabolic Syndrome and Related Disorders

The present review provides an update of the biological actions of Pycnogenol® in the treatment of metabolic syndrome and related disorders such as obesity, dyslipidaemia, diabetes and hypertension. Pycnogenol® is a French maritime pine bark extract produced from the outer bark of Pinus pinaster Ait. Subsp. atlantica. Its strong antioxidant, antiinflammatory, endothelium-dependent vasodilator activity, and also its anti-thrombotic effects make it appropriate for targeting the multifaceted pathophysiology of metabolic syndrome. Clinical studies have shown that it can reduce blood glucose levels in people with diabetes, blood pressure in mild to moderate hypertensive patients, and waist circumference, and improve lipid profile, renal and endothelial functions in metabolic syndrome. This review highlights the pathophysiology of metabolic syndrome and related clinical research findings on the safety and efficacy of Pycnogenol®. The results of clinical research studies performed with Pycnogenol® are discussed using an evidence-based, target-oriented approach following the pathophysiology of individual components as well as in metabolic syndrome overall.

Pine bark extracts: nutraceutical, pharmacological, and toxicological evaluation

Proanthocyanidins are among the most abundant constituents in pine bark extracts (PBEs). This review summarizes medical research on PBEs from Pinus pinaster, Pinus radiata, Pinus massoniana, and other less well characterized species. The precise mechanisms of the important physiologic functions of PBE components remain to be elucidated, but there is evidently great potential for the identification and development of novel antioxidant, anti-inflammatory, cardiovascular, neuroprotective, and anticancer medicines. Although toxicological data for PBEs are limited, no serious adverse effects have been reported. PBEs, therefore, may have potential as nutraceuticals and pharmaceuticals and should be safe for use as food ingredients.

A systematic review and meta-analysis of the effects of pycnogenol on plasma lipids

BACKGROUND

Pycnogenol, the standardized flavonoid-rich extract from the bark of French maritime pine (Pinus pinaster Ait), has been shown to modify a number of cardiovascular risk factors. However, that Pycnogenol modulates plasma lipid levels is unclear due to the inconsistent findings.

OBJECTIVE

To examine the impact of Pycnogenol on lipid profile through a meta-analysis of available controlled clinical trials.

METHODS

Controlled trials assessing the effects of Pycnogenol on lipid parameters (total cholesterol, low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], and triglycerides) were identified by electronic search in Medline and Scopus. Weighed mean difference (WMD) and 95% confidence interval (CI) were calculated as effect size using random-effects meta-analysis. Sensitivity and meta-regression (for Pycnogenol dose and duration of supplementation) analyses were carried out using leave-one-out and unrestricted maximum likelihood methods, respectively.

RESULTS

A total of 7 trials comprising 442 patients (226 in the Pycnogenol and 216 in the control group) were identified. Meta-analysis did not reveal any significant effect of Pycnogenol on lipid parameters: total cholesterol: WMD: -0.03 mmol/L, 95% CI: -0.34 to 0.28, P = .83; LDL-C: WMD: -0.07 mmol/L, 95% CI: -0.29 to 0.15, P = .54; HDL-C: WMD: 0.00 mmol/L, 95% CI: -0.04 to 0.05, P = .86; and triglycerides: WMD: 0.05 mmol/L, 95% CI: -0.12 to 0.23, P = .55. All these effect sizes were robust in sensitivity analyses. Apart from a dose-effect association for the effect of Pycnogenol on LDL-C, there was no other association between Pycnogenol dose or its duration of supplementation with changes in any of the lipid parameters.

CONCLUSION

Current clinical evidence does not suggest any significant effect of Pycnogenol on fasting lipid profile.