Pycnogenol enhances endothelial cell antioxidant defenses

Abstract

Reactive oxygen species (ROS) such as hydrogen peroxide (H2O2), superoxide anion (O2(-)), and hydroxyl radical (OH(•)) have been implicated in mediating various pathological events such as cancer, atherosclerosis, diabetes, ischemia, inflammatory diseases, and the aging process. The glutathione (GSH) redox cycle and antioxidant enzymes-superoxide dismutase (SOD) and catalase (CAT)-play an important role in scavenging ROS and preventing cell injury. Pycnogenol has been shown to protect endothelial cells against oxidant-induced injury. The present study determined the effects of pycnogenol on cellular metabolism of H2O2 and O2(-) and on glutathione-dependent and -independent antioxidant enzymes in bovine pulmonary artery endothelial cells (PAEC). Confluent monolayers of PAEC were incubated with pycnogenol, and oxidative stress was triggered by hypoxanthine and xanthine oxidase or H2O2. Pycnogenol caused a concentration-dependent enhancement of H2O2 and O2(-) clearance. It increased the intracellular GSH content and the activities of GSH peroxidase and GSH disulfide reductase. It also increased the activities of SOD and CAT. The results suggest that pycnogenol promotes a protective antioxidant state by upregulating important enzymatic and nonenzymatic oxidant scavenging systems.

Improvement of erectile function with Prelox: a randomized, double-blind, placebo-controlled, crossover trial

“…In the testis, e-NOS was found in Leydig cells and Sertoli cells and in the epidymis and vas deferens, illustrating the important role of NO-and e-NOS-for the human male reproductive system. 18 Decreasing amounts of e-NOS in spermatozoa with increasing age correspond to the general effect of aging on fertility.…”

Inhibitory Effect of Lutein and Pycnogenol on Lipid Peroxidation in Porcine Retinal Homogenate

“…Pycnogenol prolongs the half-life of the ascorbate radicals, as demonstrated by ESR studies [44]. In addition, pycnogenol significantly increases glutathione levels via an increase in the activity of the glutathione redox enzymes (glutathione reductase and glutathione peroxidase), and also, the enzyme activities of superoxide dismutase and catalase [45,46]. The main metabolites of pycnogenol, M1 and M2, also possess antioxidant activity and can inhibit matrix metalloproteinases [47].…”

Zinopin® – the rationale for its use as a food supplement in traveller's thrombosis and motion sickness

“…Various studies have addressed its antioxidant capacity in simplified assay systems in vitro, cultured cell models (Rong et al, 1995;Wei et al, 1997;Virgili et al, 1998a;Bayeta et al, 2000), in vivo in animals (Blazso et al, 1994;1997) and in clinical studies (Devraj et al, 2002). The antioxidant activity of two major metabolites [σ-(3, 4 dihydroxyphenyl)-γ-valerolactone] and [σ-(3-methoxy-4 hydroxphenyl)-γ-valerolactone] of Pycnogenol ® has also been shown in an independent in vitro study (Grimm et al, 2004).…”