ABSTRACT
The effects of hyperbaric oxygenation (HBO2) on acetylcholine-induced vasorelaxation (AChIR) were evaluated in male Sprague-Dawley (SD) rats randomized into four groups: healthy controls (Ctrl), diabetic rats (DM), and control and diabetic rats that underwent hyperbaric oxygenation (Ctrl+HBO2 and DM+HBO2). AChIR was measured in aortic rings, with L-NAME, indomethacin, or MS-PPOH and a combination of inhibitors. mRNA expression of eNOS, iNOS, COX-1 and COX-2 was assessed by qPCR, and protein expression of CYP4A(1-3) by Western blot. Plasma antioxidative capacity and systemic oxidative stress were determined with the ferric reducing ability of plasma (FRAP) and thiobarbituric acid-reactive substances (TBARS) assays, respectively. AChIR was preserved in all groups of rats, but mediated with different mechanisms. In all experimental groups of rats, AChIR was mediated mainly by NO, with the contribution of CYP450 vasodilator metabolites. This effect was the most prominent in the DM+HBO2 group of rats. The TBARS was significantly higher in both DM and DM+HBO2 groups compared to respective controls. eNOS expression was upregulated in the DM+HBO2 group compared to other groups, COX-1 expression was upregulated in the DM+HBO2 group compared to the control. CYP450-4A1 / A2/A3protein expression was significantly higher expressed in both hyperbaric groups compared to their respective controls. In conclusion, HBO2 affected all three vasodilator pathways and shifted AChIR to CYP450 enzymes pathway.
Subject(s)
Acetylcholine/pharmacology , Diabetes Mellitus, Experimental/physiopathology , Hyperbaric Oxygenation , Vasodilation/drug effects , Vasodilator Agents/pharmacology , Acetylcholine/antagonists & inhibitors , Amides/pharmacology , Animals , Antioxidants/analysis , Aorta/drug effects , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/metabolism , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Cytochrome P-450 Enzyme System , Diabetes Mellitus, Experimental/therapy , Enzyme Inhibitors/pharmacology , Indomethacin/pharmacology , Male , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase Type II/metabolism , Nitric Oxide Synthase Type III/metabolism , Oxidative Stress , Random Allocation , Rats , Rats, Sprague-Dawley , Thiobarbituric Acid Reactive Substances/metabolism , Vasodilation/physiology , Vasodilator Agents/antagonists & inhibitorsABSTRACT
The aim of this work was to use different assays to evaluate the antioxidant and vasodilatory properties of three typical food products from the Mediterranean area and to correlate these activities with their phenolic content. For this purpose, red wines Cannonau, liqueurs obtained by cold maceration of myrtle (Myrtus communis L.) berries and bitter honeys obtained from strawberry-tree flowers (Arbutus unedo L.) were analysed. The total phenolic (TP) content was measured spectrophotometrically with a modified Folin-Ciocalteau method and phenolic compounds were identified and dosed by HPLC-DAD and LC-MS/MS. Antioxidant activities were evaluated with DPPH, FRAP and ABTS assays and the in vitro vasodilatory effects were assessed using norepinephrine precontracted rat aortic rings. Cannonau wines and myrtle liqueurs showed high levels of TP (1978±279 and 1741±150mg GAE/L, respectively), linearly correlated to the results of FRAP, ABTS, and DPPH assays. Their maximal vasodilatory activity was 61.7±4.1% and 53.0±3.0%, respectively. Although strawberry-tree honey contained relatively high levels of phenolic compounds (922±38mg GAE/kg), it did not induce vasodilation, even at the highest dose tested (0.206g/L). These results indicate that foods with high levels of phenolic compounds should be studied using several different biological assays before being recommended to the general public as functional foods.
Subject(s)
Antioxidants/analysis , Fragaria/chemistry , Honey/analysis , Myrtus/chemistry , Plant Extracts/analysis , Vasodilator Agents/analysis , Wine/analysis , Animals , Antioxidants/pharmacology , Aorta, Thoracic/drug effects , Aorta, Thoracic/physiology , Diet, Mediterranean , Fruit/chemistry , In Vitro Techniques , Male , Plant Extracts/pharmacology , Rats , Rats, Wistar , Vasodilation/drug effects , Vasodilator Agents/pharmacologyABSTRACT
In contrast to the well-described various biological effects of grape wines, the potential effects of commonly consumed blackberry wine have not been studied. We examined in vitro antioxidant and vasodilatory effects of four blackberry wines and compared them with the effects of two red and two white grape wines. Although some blackberry wines had lower total phenolic content relative to the red grape wines, their antioxidant capacity was stronger, which may be related to a higher content of non-flavonoid compounds (most notably gallic acid) in blackberry wines. Although maximal vasodilation induced by blackberry wines was generally similar to that of red wines, blackberry wines were less potent vasodilators. Vasodilatory activity of all wines, in addition to their flavonoid and total phenolic content, was most significantly associated with their content of anthocyanins. No association of vasodilation with any individual polyphenolic compound was found. Our results indicate the biological potential of blackberry wines, which deserves deeper scientific attention.