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The cultural history of wine - theoretical background to wine therapy

100%

Fehér J., Lengyel G., Lugasi A.

Open Medicine

2007

vol. 2

issue 4

379-391

The knowledge of grape and wine is as old as the cultural history of mankind. Moderate consumption of wine can be beneficial in healthy individuals. It is also known from ancient times that it can cause acute and chronic damage when consumed in great quantities. The disinfectant effect of its use in ointments has been observed already in the antiquity. Polyphenols, among them resveratrol, have generated a great amount of scientific research due to their in vivo and in vitro antioxidant capabilities. For decades, red wine was thought to have beneficial effects on cardiovascular health. This relation was clearly established in the French Paradox phenomenon as well as in the Mediterranean diet. The French Paradox is defined as a low incidence of coronary heart disease, while consuming a diet rich in saturated fat. The cause of this phenomenon is the usually wine drinking in small quantity, supposingly in the consequence of polypenols in red wine. The use of ointments containing polyphenols of wine and the cosmetic treatments with them can be advantageous in the treatment and prevention of some diseases of the skin and the joints, due to its free radical scavenging effect. In healthy individuals the consumption of a moderate amount of 1 to 2 dl wine a day may reduce the mortality of cardiovascular diseases. However, also this quantity can be associated with detrimental effects in pregnant women, in children and in patients with various organic, particularly hepatic, diseases as well as in case of regular administration of certain medicines.

Effects of olive leaf polyphenols against H2O2 toxicity in insulin secreting β-cells

72%

Cumaoğlu A., Rackova L., Stefek M., Kartal M., Maechler P., Karasu Ç.

2011

vol. 58

issue 1

45-50

In pancreatic β-cells, although H2O2 is a metabolic signal for glucose stimulated insulin secretion, it may induce injury in the presence of increased oxidative stress (OS) as in the case of diabetic chronic hyperglycemia. Olea europea L. (olive) leaves contain polyphenolic compounds that may protect insulin-secreting cells against OS. The major polyphenolic compound in ethanolic olive leaf extract (OLE) is oleuropein (about 20 %), thus we compared the effects of OLE with the effects of standard oleuropein on INS-1 cells. The cells were incubated with increasing concentrations of OLE or oleuropein for 24 h followed by exposure to H2O2 (0.035 mM) for 45 min. H2O2 alone resulted in a significantly decreased viability (MTT assay), depressed glucose-stimulated insulin secretion, increased apoptotic and necrotic cell death (AO/EB staining), inhibited glutathione peroxidase activity (GPx) and stimulated catalase activity that were associated with increased intracellular generation of reactive oxygen species (ROS) (fluorescence DCF). OLE and oleuropein partly improved the viability, attenuated necrotic and apoptotic death, inhibited the ROS generation and improved insulin secretion in H2O2-exposed cells. The effects of oleuropein on insulin secretion were more pronounced than those of OLE, while OLE exerted a stronger anti-cytotoxic effect than oleuropein. Unlike OLE, oleuropein had no significant preserving effect on GPx; however, both compounds stimulated the activity of catalase in H2O2-exposed cells. These findings indicate different modulatory roles of polyphenolic constituents of olive leaves on redox homeostasis that may have a role in the maintenance of β-cell physiology against OS.

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1 Acta Biochimica Polonica

1 Open Medicine

1 2011

1 2007

1 Cumaoğlu A.

1 Fehér J.

1 Karasu Ç.

1 Kartal M.

1 Lengyel G.

1 Lugasi A.

1 Maechler P.

1 Rackova L.

1 Stefek M.

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The cultural history of wine - theoretical background to wine therapy

Effects of olive leaf polyphenols against H2O2 toxicity in insulin secreting β-cells