Maritime Pine Bark Extract Pycnogenol Research Articles

Review of the pharmacokinetics of French maritime pine bark extract (Pycnogenol®) in humans.

The French maritime pine bark extract Pycnogenol® is a proprietary product from Pinus pinaster Aiton. It complies with the quality specifications in the United States Pharmacopeia monograph "Pine extract" in the section of dietary supplements. Pycnogenol® is standardized to contain 65-75% procyanidins which are a variety of biopolymers consisting of catechin and epicatechin monomeric units. The effects of Pycnogenol® have been researched in a multitude of human studies. The basis for any in vivo activity is the bioavailability of constituents and metabolites of the extract. General principles of compound absorption, distribution, metabolism and elimination as well as specific data from studies with Pycnogenol® are summarized and discussed in this review. Based on plasma concentration profiles it can be concluded that low molecular weight constituents of the extract, such as catechin, caffeic and ferulic acid, taxifolin are readily absorbed from the small intestine into systemic circulation. Procyanidin oligomers and polymers are subjected to gut microbial degradation in the large intestine yielding small bioavailable metabolites such as 5-(3',4'-dihydroxyphenyl)-γ-valerolactone. After intake of Pycnogenol®, constituents and metabolites have been also detected in blood cells, synovial fluid and saliva indicating a substantial distribution in compartments other than serum. In studies simultaneously investigating concentrations in different specimen, a preferential distribution of individual compounds has been observed, e.g., of ferulic acid and 5-(3',4'-dihydroxyphenyl)-γ-valerolactone into synovial fluid compared to serum. The main route of elimination of constituents and metabolites of the French pine bark extract is the renal excretion. The broad knowledge accumulated regarding the pharmacokinetics of compounds and metabolites of Pycnogenol® constitute a rational basis for effects characterized on a cellular level and observed in human clinical studies.

Targeting Inflammation in the Diagnosis, Management, and Prevention of Cardiovascular Diseases.

Inflammation plays an important role in the development and progression of cardiovascular diseases (CVDs). Hypertension and hyperlipidemia are the key risk factors of CVDs and induce inflammation in the heart and vessels. Unhealthy diet, infection, and smoking coupled with genetic factors lead to the development of CVDs as well as induce inflammation. Risk factors of CVDs such as hypertension and hyperlipidemia along with diabetes activate nuclear factor kappa B, which regulates the transcription of immunoglobulin free light chain (FLC) κ in B cells and the production of multiple inflammatory molecules, leading to inflammation. FLCs are novel biomarkers of inflammation, and their levels have been associated with overall mortality in a general population and with cardiovascular outcomes. In this review, the role of inflammation in the pathogenesis of CVDs, new biomarkers of inflammation, and dietary options counterbalancing inflammatory processes, such as the polyphenol-rich French maritime pine bark extract Pycnogenol, are discussed.

Distribution of Constituents and Metabolites of Maritime Pine Bark Extract (Pycnogenol®) into Serum, Blood Cells, and Synovial Fluid of Patients with Severe Osteoarthritis: A Randomized Controlled Trial

The present randomized controlled study aimed to investigate the in vivo distribution of constituents or metabolites of the standardized maritime pine bark extract Pycnogenol®. Thirty-three patients with severe osteoarthritis scheduled for a knee arthroplasty were randomized to receive either 200 mg per day Pycnogenol® (P+) or no treatment (Co) over three weeks before surgery. Serum, blood cells, and synovial fluid samples were analyzed using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization (LC-ESI/MS/MS). Considerable interindividual differences were observed indicating pronounced variability of the polyphenol pharmacokinetics. Notably, the highest polyphenol concentrations were not detected in serum. Catechin and taxifolin primarily resided within the blood cells while the microbial catechin metabolite δ-(3,4-dihydroxy-phenyl)-γ-valerolactone, ferulic, and caffeic acid were mainly present in synovial fluid samples. Taxifolin was detected in serum and synovial fluid exclusively in the P+ group. Likewise, no ferulic acid was found in serum samples of the Co group. Calculating ratios of analyte distribution in individual patients revealed a simultaneous presence of some polyphenols in serum, blood cells, and/or synovial fluid only in the P+ group. This is the first evidence that polyphenols distribute into the synovial fluid of patients with osteoarthritis which supports rationalizing the results of clinical efficacy studies.

Effects of a supplement combining Pycnogenol® and l-arginine aspartate on lower urinary dysfunction compared with saw palmetto extract

ObjectivesLower urinary tract symptoms (LUTS) and sexual dysfunction (SDys) are common problems that affect quality of life (QOL) in elderly men. In addition to prescribed drugs, many over-the-counter medications including supplements are used to treat QOL diseases. Phosphodiesterase inhibitors are reported to be effective for both LUTS and SDys by increasing nitric oxide levels. French maritime pine bark extract Pycnogenol®, which is a potent nitric oxide donor, is reported to be effective for SDys. However, no reports have been published on whether it ameliorates LUTS. DesignOpen-labeled, randomized study. The effects of two supplements, Nokogiriyashi EX® containing 160 mg saw palmetto (SP) extract per tablet and Edicare® containing 10 mg of Pycnogenol®, 115 mg of l-arginine and 92 mg of aspartate (PAA) per tablet on International Prostate Symptom Score (IPSS), IPSS–QOL, Overactive Bladder Symptom Score (OABSS), International Index of Erectile Function 5 (IIEF5), Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF), urinary 8-OHdG and uroflowmetry (UFM) of total 40 men with LUTS and SDys were examined. Results19 subjects were instructed to take two tablets of SP, on the other 20 were on four tablets of PAA for 16 weeks. IPSS and IPSS–QOL showed statistically significant improvements in both groups. OABSS and IIEF5 were significantly improved in the PAA group. Conversely, ICIQ-SF, 8-OHdG and UFM did not change in either group. ConclusionsPAA might be an effective therapeutic alternative for elderly patients with LUTS and SDys.

Facilitated cellular uptake and suppression of inducible nitric oxide synthase by a metabolite of maritime pine bark extract (Pycnogenol)

Many natural products exhibit anti-inflammatory activity by suppressing excessive nitric oxide (NO) production by inducible NO synthase (iNOS). The maritime pine bark extract Pycnogenol has been formerly shown to decrease nitrite generation, taken as an index for NO, but so far it was not clear which constituent of the complex flavonoid mixture mediated this effect. The purpose of this study was to elucidate whether the in vivo generated Pycnogenol metabolite M1 (δ-(3,4-dihydroxyphenyl)-γ-valerolactone) displayed any activity in the context of induction of iNOS expression and excessive NO production. For the first time we show that M1 inhibited nitrite production (IC50 1.3μg/ml, 95% CI 0.96–1.70) and iNOS expression (IC50 3.8μg/ml, 95% CI 0.99–14.35) in a concentration-dependent fashion. This exemplifies bioactivation by metabolism because the M1 precursor molecule catechin is only weakly active. However, these effects required application of M1 in the low-micromolar range, which was not consistent with concentrations previously detected in human plasma samples after ingestion of maritime pine bark extract. Thus, we investigated a possible accumulation of M1 in cells and indeed observed high-capacity binding of this flavonoid metabolite to macrophages, monocytes, and endothelial cells. This binding was distinctly decreased in the presence of the influx inhibitor phloretin, suggesting the contribution of a facilitated M1 transport into cells. In fact, intracellular accumulation of M1 could explain why in vivo bioactivity can be observed with nanomolar plasma concentrations that typically fail to exhibit measurable activity in vitro.

Improvement of signs and symptoms of chronic venous insufficiency and microangiopathy with Pycnogenol®: A prospective, controlled study

The aim of this study was to evaluate the clinical efficacy of standardized French maritime pine bark extract Pycnogenol in patients with severe chronic venous insufficiency (CVI). 98 subjects with symptomatic CVI and edema were randomly assigned to one group treated with 150 mg Pycnogenol a day only, another group with stockings only and a third group with both Pycnogenol and elastic stockings. The average ambulatory venous pressure (AVP) at inclusion was 58+/-7 mm Hg (range 48-60 mm Hg) with a refilling time (RT)<12 s (average 7+/-2 s). The duration of the disease was on average 6.0+/-3.1 years. There were no differences in AVP or RT among the 3 groups at inclusion and microcirculatory and clinical evaluations were comparable. After 8 weeks treatment there was a significant decrease of rate of ankle swelling, resting flux, transcutaneous pO(2) and clinical symptom scores in all groups with significantly better results for the combination treatment. Pycnogenol alone was more effective than compression alone for all parameters (p<0.05). No side-effects were observed; compliance and tolerability were very good. This study corroborates a significant clinical role for Pycnogenol in the management, treatment and control of CVI also in combination with compression.

Single and multiple dose pharmacokinetics of maritime pine bark extract (Pycnogenol) after oral administration to healthy volunteers

BackgroundSince plant extracts are increasingly used as phytotherapeutics or dietary supplements information on bioavailability, bioefficacy and safety are warranted. We elucidated the plasma kinetics of genuine extract components and metabolites after single and multiple ingestion of the standardized maritime pine bark extract Pycnogenol (USP quality) by human volunteers.MethodsEleven volunteers received a single dose of 300 mg pine bark extract, five volunteers ingested 200 mg daily for five days to reach steady state concentrations. Plasma samples were obtained before and at defined time points after intake of the extract. Samples were analyzed by HPLC with ion-pair reagents and simultaneous UV and electrochemical detection.ResultsWe quantified total plasma concentrations of catechin, caffeic acid, ferulic acid, taxifolin and the metabolite M1 (δ-(3,4-dihydroxy-phenyl)-γ-valerolactone). Additionally, we describe plasma time courses and steady state appearance of ten so far unknown compounds, U1 to U10. After single ingestion, compounds derived from the extract were rapidly absorbed and the majority of them were detectable over whole experimental period of 14 h. The analysis of steady state plasma samples revealed significant phase II metabolism.ConclusionWe present the first systematic pharmacokinetic analysis of compounds derived from maritime pine bark extract. Beyond the known constituents and metabolites we uncovered the plasma time courses of ten unknown compounds. In concert with our previous detection of anti-inflammatory bioefficacy of these plasma samples ex vivo we suggest that constituents and metabolites of Pycnogenol bear potential for disclosure of novel active principles.

The effects of Pycnogenol on DNA damage in vitro and expression of superoxide dismutase and HP1 in Escherichia coli SOD and catalase deficient mutant cells

The procyanidin-rich French maritime pine bark extract Pycnogenol (PYC) is believed to be an antioxidant. To access whether PYC protects DNA against Fenton reaction radicals, pUC 19 plasmid DNA was damaged by OH- radicals generated from Fe(II) plus H2O2 in the presence and absence of PYC. DNA damage was quantified by measuring decreases in supercoiled DNA (SC-DNA) using agarose gel electrophoresis. The results showed that PYC (50 microg/mL) did not inhibit DNA damage from Fenton reaction-generated oxyradicals, when the Fenton reaction was allowed to proceed. However, PYC did protect against DNA damage when added prior to the initiation of the Fenton reaction, suggesting that protection resulted from chelation of Fe rather than from the scavenging of radicals. Moreover, we unexpectedly observed PYC-associated DNA breakage, which was dose- and time- dependent. Other antioxidants such as desferrioxamine (DFO) including butylated hydroxyltoluene (BHT), curcumin and alpha-tocopherol exhibited protective effects against DNA damage caused by the Fenton reaction. Subsequently, we assessed the possible pro-oxidant function of PYC on DNA damage in E. coli SOD deficient mutants under oxidative stress, after observing that PYC can induce SOD under oxidative stress. Although, PYC did not enhance DNA damage, it likewise did not protect against oxidative stress-mediated DNA damage. All together, our data indicate that PYC under some circumstances can enhance oxidative stress-mediated DNA damage in vitro and in vivo.

Antioxidant activity and inhibition of matrix metalloproteinases by metabolites of maritime pine bark extract (pycnogenol)

The procyanidin-rich maritime pine bark extract Pycnogenol has well-documented antioxidant and anti-inflammatory activity. After oral administration of Pycnogenol two major metabolites are formed in vivo, δ-(3,4-dihydroxyphenyl)-γ-valerolactone (M1) and δ-(3-methoxy-4-hydroxyphenyl)-γ-valerolactone (M2). We elucidated the effects of these metabolites on matrix metalloproteinases (MMPs) and determined their antioxidant activity to understand their contribution to the effects of maritime pine bark extract. We discovered strong inhibitory effects of M1 and M2 toward the activity of MMP-1, MMP-2, and MMP-9. On a microgram-per-milliliter basis both metabolites appeared more active than Pycnogenol. The metabolites were more effective than their metabolic precursor (+)-catechin in MMP inhibition. On a cellular level, we detected highly potent prevention of MMP-9 release by both metabolites, with concentrations of 0.5 μM resulting in about 50% inhibition of MMP-9 secretion. M1 was significantly more effective in superoxide scavenging than (+)-catechin, ascorbic acid, and trolox, while M2 displayed no scavenging activity. Both metabolites exhibited antioxidant activities in a redox-linked colorimetric assay, with M1 being significantly more potent than all other compounds tested. Thus, our data contribute to the comprehension of Pycnogenol effects and provide a rational basis for its use in prophylaxis and therapy of disorders related to imbalanced or excessive MMP activity.

Solar ultraviolet-induced erythema in human skin and nuclear factor-kappa-B–dependent gene expression in keratinocytes are modulated by a French maritime pine bark extract

The procyanidin-rich French maritime pine bark extract Pycnogenol (PBE) has been investigated for its effect in protecting human skin against solar UV-simulated light-induced erythema. Twenty-one volunteers were given an oral supplementation of Pycnogenol: 1.10 mg/kg body weight (b. wt.)/d for the first 4 weeks and 1.66 mg/kg b. wt./d for the next 4 weeks. The minimal erythema dose (MED) was measured twice before supplementation (baseline MED), once after the first 4 weeks of supplementation, and a last time at the end of the study. The UVR dose necessary to achieve 1 MED was significantly increased during PBE supplementation. Since the activation of the pro-inflammatory and redox-regulated transcription factor NF-κB is thought to play a major role in UVR-induced erythema, the effect of PBE was also investigated in the human keratinocyte cell line HaCaT. PBE, added to the cell culture medium, inhibited UVR-induced NF-κB–dependent gene expression in a concentration-dependent manner. However, NF-κB–DNA-binding activity was not prevented, suggesting that PBE affects the transactivation capacity of NF-κB. These data indicate that oral supplementation of PBE reduces erythema in the skin. Inhibition of NF-κB–dependent gene expression by PBE possibly contributes to the observed increase in MED.