ABSTRACT
BACKGROUND: Silver fir trunk extract (SFTE) is a complex mixture of antioxidative polyphenols (lignans and phenolic acids) from the trunks of silver fir trees (Abies alba, lignum). In our previous study, we have shown that SFTE exerts strong antioxidative and protective effects against atherogenic, diet-induced arterial wall damage. OBJECTIVE: The aim of the present study was to test the potential protective effects of SFTE and its compounds, two phenolic acids (p-coumaric and protocatechuic acids) in ischemia-reperfusion injury of isolated rat hearts. DESIGN: Isolated hearts of Wistar rats aged 4-8 weeks were exposed to perfusion, ischemia, and reperfusion periods. The experiments were performed using the following five groups: control, SFTE (10 µg/L), SFTE (100 µg/L), protocatechuic acid, and p-coumaric. Aortas were isolated to measure vascular responses in the presence of Nω-Nitro-L-arginine. RESULTS: SFTE dose-dependently reduced ischemic-reperfusion heart damage, which was indicated as the decrease in the lactate dehydrogenase (LDH) release rate and arrhythmias duration by 80% and an increase in coronary flow rate during the reperfusion period. Two tested compounds (p-coumaric and protocatechuic acids) acted less cardioprotective, since they decreased the duration of arrhythmias only by 40 and 45%, respectively, and did not decrease LDH release rates during the reperfusion period. Only p-coumaric acid increased coronary flow rates, whereas protocatechuic acid did not. CONCLUSIONS: We conclude that the SFTE exerted the strongest cardioprotective effect, whereas its constituents (the p-coumaric and protocatechuic acids) were less effective in inducing cardioprotection.
ABSTRACT
BACKGROUND: Diet, rich in plant polyphenols prevents atherogenesis that manifests as reduced vascular relaxation and formation of plaques. HYPOTHESIS: Atherosclerosis could be reduced by the intake of silver fir (Abies alba) extract (SFTE), rich in polyphenols. STUDY DESIGN: Chronic, in vivo treatment animal study. METHODS: Guinea pigs (Cavia porcellus) were fed for 8 weeks with one of the following three diets: atherogenic, basic or atherogenic + SFTE. After isolation, we measured the relaxation and contractile responses of the thoracic aorta. Additionally, we measured the area of fatty plaques on the aortic walls. RESULTS: Compared to the basic diet, the atherogenic diet decreased the ability of the aorta to relax by 63% (p < 0.001). The addition of SFTE to the atherogenic diet improved the aorta relaxation response compared to that of the atherogenic diet without SFTE (the decrease relative to the basic diet was 26%, p < 0.001). The aorta contractility did not differ between the groups. The SFTE group generated significantly fewer atherosclerotic plaques than did the atherogenic group. The areas of atherosclerotic plaques were 7.4, 0.3 and 1.6% in the aortas of guinea pigs receiving atherogenic, basic or atherogenic + SFTE diets, respectively. CONCLUSIONS: In a guinea pig model, prolonged treatment with antioxidative polyphenol-rich SFTE prevents aortic functional and morphological changes caused by an atherogenic diet.
Subject(s)
Abies/chemistry , Arteries/drug effects , Atherosclerosis/prevention & control , Diet, Atherogenic/adverse effects , Plant Extracts/chemistry , Animals , Aorta, Thoracic/drug effects , Female , Free Radical Scavengers/chemistry , Guinea Pigs , Male , Plant Stems/chemistry , Plaque, Atherosclerotic/prevention & controlABSTRACT
Buckwheat contains many healthy nutrients, and its consumption is therefore increasing. Buckwheat also contains fluorescent phototoxic fagopyrins. A systematic review of fagopyrins and the phototoxicity of buckwheat found that reliable quantitative data on fagopyrin toxicity are not yet available. Generally, buckwheat seeds, flour, and teas are safe in normal amounts. Diets extensively composed of buckwheat sprouts, herbs, and particularly flowers or of fagopyrin-rich buckwheat extracts may cause fagopyrism. A reference standard is needed, as it would enable the accurate evaluation of fagopyrin content in buckwheat products and would allow proper testing of their as yet unknown physical, chemical, and biological characteristics.
