Effects of ginsenosides on vasodilator nerve actions in the rat perfused mesentery are mediated by nitric oxide

Ginseng in vascular dysfunction: A review of therapeutic potentials and molecular mechanisms

Vascular dysfunction can lead to a variety of fatal diseases, including cardiovascular and cerebrovascular diseases, metabolic syndrome, and cancer. Although a large number of studies have reported the therapeutic effects of natural compounds on vascular-related diseases, ginseng is still the focus of research. Ginseng and its active substances have bioactive effects against different diseases with vascular dysfunction. In this review, we summarized the key molecular mechanisms and signaling pathways of ginseng, its different active ingredients or formula in the prevention and treatment of vascular-related diseases, including cardiac-cerebral vascular diseases, hypertension, diabetes complications, and cancer. Moreover, the bidirectional roles of ginseng in promoting or inhibiting angiogenesis have been highlighted. We systematically teased out the relationship between ginseng and vascular dysfunction, which could provide a basis for the clinical application of ginseng in the future.

Ginseng in vascular dysfunction: A review of therapeutic potentials and molecular mechanisms

Vascular dysfunction can lead to a variety of fatal diseases, including cardiovascular and cerebrovascular diseases, metabolic syndrome, and cancer. Although a large number of studies have reported the therapeutic effects of natural compounds on vascular‐related diseases, ginseng is still the focus of research. Ginseng and its active substances have bioactive effects against different diseases with vascular dysfunction. In this review, we summarized the key molecular mechanisms and signaling pathways of ginseng, its different active ingredients or formula in the prevention and treatment of vascular‐related diseases, including cardiac‐cerebral vascular diseases, hypertension, diabetes complications, and cancer. Moreover, the bidirectional roles of ginseng in promoting or inhibiting angiogenesis have been highlighted. We systematically teased out the relationship between ginseng and vascular dysfunction, which could provide a basis for the clinical application of ginseng in the future.

Effects of dietary supplementation of red ginseng marc and α-tocopherol on the growth performance and meat quality of broiler chicken

BACKGROUND

This study aimed to determine the effect of supplementation of broiler diets with red ginseng marc and α-tocopherol on the growth performance and meat quality during a 35-day feeding period. A total of 225 Hubbard male broiler chicks were fed diets supplemented with 0%, 1%, 2% and 3% red ginseng marc, or 2% red ginseng marc + 200 IU α-tocopherol kg(-1) and randomly allocated to five dietary groups (15 floor pens), so that each group had three replicates and 15 broilers per pen (0.09 m(2) per bird).

RESULTS

There were no differences among the treated groups with regard to growth performance and proximate composition, except for mortality and crude fat in broilers. Serum cholesterol levels were lower in the chickens receiving diets supplemented with red ginseng marc and α-tocopherol than those in the control. With the exception of water-holding capacity or shear force values, increasing levels of red ginseng marc and a combination of red ginseng marc and α-tocopherol affected chicken thigh meat quality by decreasing the pH and thiobarbituric acid reactive substance and increasing the total phenol and DPPH-radical scavenging compared with those in the control. Broiler diets with increasing levels of red ginseng marc and the combination of red ginseng marc and α-tocopherol did not affect the color of thigh muscle, but the treatment significantly increased a* values.

CONCLUSION

Supplementation of poultry diets with 3% red ginseng marc markedly reduced mortality and serum cholesterol levels and remarkably improved meat quality in broilers.

Nitric oxide, human diseases and the herbal products that affect the nitric oxide signalling pathway

1. Nitric oxide (NO) is formed enzymatically from l-arginine in the presence of nitric oxide synthase (NOS). Nitric oxide is generated constitutively in endothelial cells via sheer stress and blood-borne substances. Nitric oxide is also generated constitutively in neuronal cells and serves as a neurotransmitter and neuromodulator in non-adrenergic, non-cholinergic nerve endings. Furthermore, NO can also be formed via enzyme induction in many tissues in the presence of cytokines. 2. The ubiquitous presence of NO in the living body suggests that NO plays an important role in the maintenance of health. Being a free radical with vasodilatory properties, NO exerts dual effects on tissues and cells in various biological systems. At low concentrations, NO can dilate the blood vessels and improve the circulation, but at high concentrations it can cause circulatory shock and induce cell death. Thus, diseases can arise in the presence of the extreme ends of the physiological concentrations of NO. 3. The NO signalling pathway has, in recent years, become a target for new drug development. The high level of flavonoids, catechins, tannins and other polyphenolic compounds present in vegetables, fruits, soy, tea and even red wine (from grapes) is believed to contribute to their beneficial health effects. Some of these compounds induce NO formation from the endothelial cells to improve circulation and some suppress the induction of inducible NOS in inflammation and infection. 4. Many botanical medicinal herbs and drugs derived from these herbs have been shown to have effects on the NO signalling pathway. For example, the saponins from ginseng, ginsenosides, have been shown to relax blood vessels (probably contributing to the antifatigue and blood pressure-lowering effects of ginseng) and corpus cavernosum (thus, for the treatment of men suffering from erectile dysfunction; however, the legendary aphrodisiac effect of ginseng may be an overstatement). Many plant extracts or purified drugs derived from Chinese medicinal herbs with proposed actions on NO pathways are also reviewed.

Efficacy and safety of ginseng

Ginseng (Panax ginseng, C.A. Meyer) has been a popular herbal remedy used in eastern Asian cultures for thousands of years. In North America, the ginseng species indigenous to both Canada and the United States (Panax quinquefolium) represents an important industry for both domestic and export markets. There are numerous theories and claims describing the efficacy of ginseng, which can combat stress, enhance both the central and immune systems and contribute towards maintaining optimal oxidative status against certain chronic disease states and aging. Risk issues concerning the safety of ginseng at recommended dosages are less prominent and scientifically based. While some epidemiological or clinical studies have reported indications of efficacy for specific health benefits or potential toxicity, there are an equal number of studies that provide contradictory evidence. This situation has led to questionable conclusions concerning specific health benefits or risks associated with ginseng. Recent advances in the development of standardized extracts for both Panax ginseng (G-115) and Panax quinquefolius (CNT-2000) have and will continue to assist in the assessment of efficacy and safety standards for ginseng products. This paper reviews the scientific literature and evidence for ginseng efficacy and safety derived mostly from in vitro and animal studies and places emphasis on the need for more randomized, double-blinded, placebo clinical studies that can provide unequivocal conclusions. An example of the efficacy and safety of ginseng is provided with the description of biological activity of a North American ginseng extract (NAGE), which includes illustrating mechanisms for antioxidant activity without prooxidant properties.

The direct release of nitric oxide by gypenosides derived from the herb Gynostemma pentaphyllum

Herbal medicines are increasingly being utilized to treat a wide variety of disease processes. Gypenosides are triterpenoid saponins contained in an extract from Gynostemma pentaphyllum and are reported to be effective in the treatment of cardiovascular diseases; however, the mechanism underlying the therapeutic effect is not known. We tested the hypothesis that gypenosides extracted from G. pentaphyllum elicit vasorelaxation through the direct release of endothelium-derived nitric oxide. Nitric oxide production in bovine aortic endothelial cells grown under standard tissue culture conditions was quantitated using a chemiluminescence method. Arterial vasomotion was assayed using isolated porcine coronary artery rings under standard isometric recording conditions. The extract of G. pentaphyllum at 0.1-100 microg/ml elicited concentration-dependent vasorelaxation of porcine coronary rings that was antagonized by the nitric oxide synthase inhibitor N(G)-nitro-l-arginine methyl ester. Indomethacin had no significant effect on G. pentaphyllum-induced relaxation. The G. pentaphyllum extract elicited a concentration-dependent increase in nitric oxide production from cultured bovine aortic endothelial cells. At the concentrations utilized, there was no morphological evidence for cellular toxicity. These results demonstrate that extracts of G. pentaphyllum directly stimulate nitric oxide release, but not prostanoid production. Nitric oxide production in response to gypenosides may be one mechanism whereby this herbal medicine elicits its therapeutic effects.