The red wine antioxidant resveratrol protects isolated rat hearts from ischemia reperfusion injury

The consumption of red wine has been reported to impart a greater benefit in the prevention of coronary heart disease than the consumption of other alcoholic beverages. This beneficial effect is increasingly being attributed to certain antioxidants comprising the polyphenol fraction of red wine such as transresveratrol. In the present study, we investigated the potential cardioprotective effects of resveratrol in the face of ischemia reperfusion (I/R) injury. Isolated perfused working rat hearts after stabilization were perfused with Krebs-Henseleit Bicarbonate buffer (KHB) either in the presence or absence of transresveratrol (RVT) at a concentration of 10 microM for 15 min prior to subjecting them to 30 min of global ischemia followed by 2 h of reperfusion. Left ventricular functions were monitored at various timepoints throughout the reperfusion period to assess the extent of postischemic recovery in comparison with baseline values. Coronary perfusate samples were also collected to determine malonaldehyde (MDA) levels. The results demonstrated that RVT exhibited significant myocardial protection. This was evidenced by improved recovery of post-ischemic ventricular function including developed pressure and aortic flow as compared to the control group (KHB). Values for developed pressure in the RVT-treated group were significantly higher than those in the control group throughout the reperfusion period (71.09+/-4.88 mm Hg vs. 58.47+/-3.88 mm Hg, 68.87+/-5.07 mm Hg vs. 49.74+/-2.65 mm Hg and 51.67+/-3.95 mm Hg vs. 30.50+/-4.80 mm Hg at reperfusion timepoints R-15, R-60, and R-120, respectively). From R-30 onwards, aortic flow was markedly higher in the RVT treated group as compared with the control group, the differences being most significant at R-90 (32.45+/-2.19 ml/min vs. 19.83+/-1.62 ml/min) and R-120 (27.15+/-2.27 ml/min vs. 14.10+/-1.69 ml/min). In contrast to the KHB treated group, the RVT-treated group displayed significant reduction in MDA formation especially in the immediate early reperfusion period (63.71+/-8.19 pM/ml vs. 130.86+/-4.76 pM/ml, 63.84+/-15.62 pM/ml vs. 156.99+/-18.93 pM/ml, 71.29+/-2.80 pM/ml vs. 129.5+/-10.30 pM/ml and 56.25+/-5.79 pM/ml vs. 127.99+/-3.50 pM/ml at timepoints R-1, R-3, R-5, and R-7, respectively) indicating a reduction in I/R injury related oxidative stress. Infarct size was markedly reduced in the RVT group when compared with the control group (10.57+/-0.35% vs. 36.27+/-5.28%). In vitro studies revealed RVT to be a potent scavenger of peroxyl radicals suggestive of a probable mechanism involved in the protective ability of RVT. The results of this study indicate that resveratrol possesses cardioprotective effects which may be attributed to its peroxyl radical scavenging activity.

Activity in vitro of resveratrol on granulocyte and monocyte adhesion to endothelium

BACKGROUND

Resveratrol is a phytoalexin present in red wine. It has been shown to protect LDL from peroxidative degradation.

OBJECTIVE

In consideration of the low plasma concentration of orally adsorbed resveratrol (which is insufficient for antioxidant protection of LDL), we studied another effect of the compound.

DESIGN

Because resveratrol is a tyrosine kinase inhibitor like other members of the tyrphostin family, we hypothesized that it has the ability to modify intracellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) expression by stimulated endothelial cells. We studied the ability of resveratrol to inhibit such adhesion molecule expression and to block the adhesion of monocytes and granulocytes to endothelial cells.

RESULTS

We showed that resveratrol, at concentrations as low as 1 micromol/L and 100 nmol/L, significantly inhibited ICAM-1 and VCAM-1 expression by tumor necrosis factor alpha (TNF-alpha)-stimulated human umbilical vein endothelial cells and lipopolysaccharide-stimulated human saphenous vein endothelial cells (HSVEC), respectively. In addition, we showed that resveratrol induced a significant inhibition in the adhesion of U937 monocytoid cells to lipopolysaccharide-stimulated HSVEC. Such inhibition was comparable with that obtained when anti-VCAM-1 monoclonal antibody was used instead of resveratrol. Resveratrol also significantly inhibited the adhesion of neutrophils to TNF-alpha-stimulated NIH/3T3 ICAM-1-transfected cells, whereas neutrophils activated by formyl-methionyl-leucyl-phenylalanine did not significantly modify adhesion to NIH/3T3 ICAM-1-transfected cells.

CONCLUSIONS

Our results indicate activity of resveratrol on endothelial cells and a new interpretation of an effect independent of its antioxidant function.

Resveratrol, a polyphenol found in wine, reduces ischemia reperfusion injury in rat kidneys

Reactive oxygen species have been implicated in the pathophysiology of renal ischemia reperfusion injury. Antioxidants including polyphenolics have been found to protect renal cells from the cellular injury induced by ischemia and reperfusion. Resveratrol, a stilbene polyphenol found in grapes and red wine, has recently been found to protect isolated rat heart from ischemia reperfusion injury. This study was sought to determine if resveratrol could also protect renal cells from ischemic injury. Male Wistar rats were treated with control, resveratrol (0.23 microg/kg), vehicle used to solubilize resveratrol, and resveratrol plus L-NAME (15 mg/kg body wt), a nitric oxide blocker. Our results demonstrated that resveratrol administration reduced the mortality of ischemic rats from 50% to 10% and renal damage was reduced as indicated by histologic examination and serum creatinine level. The short-term administration of resveratrol also inhibited renal lipid peroxidation induced by ischemia and reperfusion both in cortex and in medulla. Electron paramagnetic resonance detected an increased formation of nitric oxide in the resveratrol-treated kidney that was reduced to the baseline value after treating the rats with L-NAME in addition to resveratrol. The results suggest that resveratrol reduced the renal ischemia reperfusion injury through a nitric oxide-dependent mechanism.

Polyphenols: From Theory to Practice

BACKGROUND

The importance of polyphenols in human health is well known; these compounds are common in foods, such as fruits, vegetables, spices, extra virgin olive oil and wine. On the other hand, the different factors that modulate the biological activity of these compounds are less well known. Conceptualization of the work: In this review we took into account about 200 relevant and recent papers on the following topics: "polyphenols bioavailability", "polyphenols matrix effect", "food matrix effect", "polyphenols-cytochromes interaction", after having reviewed and updated information on chemical classification and main biological properties of polyphenols, such as the antioxidant, anti-radical and anti-inflammatory activity, together with the tricky link between in vitro tests and clinical trials.

KEY FINDINGS

the issue of polyphenols bioavailability and matrix effect should be better taken into account when health claims are referred to polyphenols, thus considering the matrix effect, enzymatic interactions, reactions with other foods or genetic or gender characteristics that could interfere. We also discovered that in vitro studies often underrate the role of phytocomplexes and thus we provided practical hints to describe a clearer way to approach an investigation on polyphenols for a more resounding transfer to their use in medicine.

Myocardial protection with red wine extract

Cardioprotective action of red wine was studied by preperfusing isolated rat hearts with ethanol-free red wine extract for 15 min before subjecting them to 30 min of global ischemia followed by 2 h of reperfusion. Four other group of rats were studied under identical conditions, of which one served as control; one was treated with 10 microM trans-resveratrol (RVT), one of the major antioxidants found in red wines; another, with 0.07% ethanol; and another, with 0.07% ethanol plus 10 microM RVT. The results of our study demonstrated that both red wine extract and RVT were equally cardioprotective, as evidenced by their abilities to improve postischemic ventricular functions including developed pressure and aortic flow. Developed pressure values at 60 min after reperfusion were 81.8 +/- 1.2 and 68.8 +/- 4.1 mm Hg for the red wine extract and RVT groups, respectively, versus 49.7 +/- 2.7 mm Hg for the control group. These compounds also reduced myocardial infarct size compared with the control hearts (20.1 +/- 0.5% and 10.5 +/- 0.3% for red wine extract and RVT groups, respectively, vs. 29.9 +/- 3.1% for the control group). The ethanol-treated group displayed slightly better functional recovery, which deteriorated sharply toward the end of the reperfusion period, and the extent of infarction was comparable to that of the control group (31.5 +/- 0.9%). In the ethanol plus RVT group, postischemic contractile function was significantly better than control, and infarct size also was reduced to 20.9 +/- 0.7%. The amount of malonaldehyde formation in the postischemic myocardium was reduced by red wine extract and RVT, indicating a reduction of oxidative stress developed in the ischemic reperfused myocardium. In vitro studies revealed that red wine extract is a potent antioxidant as evidenced by its ability to scavenge peroxyl radical in vitro. Taken together, the results of our study indicate that red wines are cardioprotective by their ability to function as an in vivo antioxidant.

Comparison of cardioprotective abilities between the flesh and skin of grapes

Recent studies have documented that grapes and grape juices are equally cardioprotective as red wine. The existing reports implicate that the skin and seeds of the grapes containing polyphenolic antioxidants are instrumental for the cardioprotective properties of grapes. The present study examines if the flesh of grapes also possesses any cardioprotective abilities. Three groups of randomly selected rats were fed, water only (control), flesh of the grapes (2.5 mg/kg b. wt.) or the skins (2.5 mg/kg b. wt.) for 30 days. At the end of the 30 days, isolated perfused hearts were made ischemic for 30 min followed by 2 h of reperfusion in the working mode. The results demonstrated that both flesh and skin of the grapes could protect the hearts from ischemic reperfusion injury as evidenced by improved postischemic ventricular recovery and reduced myocardial infarct size. High performance liquid chromatography (HPLC) revealed that skin and flesh contained comparative amounts of glucose, fructose, tartaric acid, malic acid, shikimic acid, and trans-caftaric acid. In addition, the flesh contained reduced amounts (compared to skin) of cis-coutaric, trans-coutaric, caffeic, p-coumaric, cinnamics, and catechin/epicatechin. Total polyphenolic index was also lower in flesh compared to skin. The anthocyanins were present exclusively in the skin. Electron paramagnetic resonance (EPR) spectrometry of hydroxy radicals indicated that both flesh and skins possessed equal amount of ROS scavenging activities. Total malonaldehyde content in the heart was reduced comparatively with either flesh or skin. The results indicate for the first time that the flesh of grapes are equally cardioprotective as skin, and antioxidant potential of skin and flesh of grapes are comparable with each other despite of the fact that flesh does not possess any anthocyanin activities.

Anti-Inflammatory Effect of White Wine in CKD Patients and Healthy Volunteers

Background: Mediterranean-style diet has been considered for its important beneficial effects on the progression of CV disease. Wine is an important component of the Mediterranean diet, and moderate wine drinkers have lower mortality rates than nondrinkers and heavy drinkers in epidemiologic studies. The beneficial effects of red wine are thought to be dependent on the polyphenol compounds such as resveratrol that exhibit potent antioxidant activity. However, white wine, although lacking polyphenols, contains simple phenols, such as tyrosol (Tyr) and hydroxytyrosol (OH-Tyr), characteristic also of extra-virgin olive oil, which may share similar antioxidant and inflammatory properties. Patients and Methods: The effect of white wine and extra-virgin olive oil on inflammatory markers was evaluated in 10 healthy volunteers and in 10 patients with CKD (chronic kidney disease) K-DOQI stage III-IV in a prospective, single blind, randomized, cross-over trial. After two weeks of wash-out from alcoholic beverages, subjects were randomized to a cross-over design A-B or B-A of a 2-week treatment with white wine (4 ml/kg body weight, 0.48 g/kg of alcohol 12%, corresponding to 2-3 glasses/daily) and extra-virgin olive oil (treatment A) or extra-virgin olive oil alone (treatment B). The two study periods were separated by a two-week wash-out period. At baseline and at the end of each treatment, plasma levels of inflammatory markers C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interleukin-8 (IL-8) concentration were determined. Urinary levels of Tyr, OH-Tyr, and their metabolites were measured at the same time. Results: During combined consumption of white wine and extra-virgin olive oil (treatment A), plasma levels of CRP and IL-6 decreased from 4.1 ± 1.8 to 2.4 ± 1.9 mg/l (p < 0.05) and from 5.3 ± 3.2 to 3.4 ± 2.3 mg/l (p < 0.05) in CKD patients. CRP decreased from 2.6 ± 1.2 to 1.9 ± 0.9 mg/l (p < 0.05), and IL-6 decreased from 2.2 ± 1.8 to 1.7 ± 1.3 mg/l (p = ns) in healthy volunteers. No significant variation versus baseline was observed during treatment B. A significant increase in urinary Tyr and OH-Tyr was observed during treatment A (white wine and extra-virgin olive oil). Conclusions: Plasma markers of chronic inflammation were significantly reduced in CKD patients during the combined consumption of white wine and olive oil, suggesting a possible anti-inflammatory effect of this nutritional intervention.

The introduction of the stilbene synthase gene enhances the natural antiradical activity of Lycopersicon esculentum mill

Tomato (Lycopersicon esculentum) is a vegetable rich in antioxidants, such as lycopene, lutein, and zeaxanthin. Their presence is responsible for the characteristic ability of this product to inhibit the formation of reactive oxygen species, including singlet oxygen. The grapes and wines derived from grapes also contain powerful antioxidants. The antioxidant effect is derived from the polyphenols such as resveratrol and proanthocyanidin. Resveratrol is phytoalexin that is synthesized via the activation of the gene, stilbene synthase (STS). We decided to determine if the introduction of this gene into Lycopersicon esculentum Mill could modify its antioxidant activity. Using Electronic Paramagnetic Resonance (EPR) spectroscopy, which permits the detection of antiradical activity, especially *OH (hydroxyl radical), we showed that the antioxidant activity of the products, into which the gene STS had been introduced, was almost double than that of natural products and that their activity was especially pronounced due to ripening. Moreover, resveratrol concentrations in modified tomatoes were much higher than that found in the individual fruit. In the isolated hearts subjected to ischemia/reperfusion, the rats fed with modified tomato exhibited better cardiac performance, reduced myocardial infarct size and decreased number of apoptotic cardiomyocytes, and reduced oxidative stress compared to unmodified tomato or resveratrol alone indicating superior cardioprotective abilities of modified tomatoes.

Association between taste receptor (TAS) genes and the perception of wine characteristics

Several studies have suggested a possible relationship between polymorphic variants of the taste receptors genes and the acceptance, liking and intake of food and beverages. In the last decade investigators have attempted to link the individual ability to taste 6-n-propylthiouracil (PROP) and the sensations, such as astringency and bitterness, elicited by wine or its components, but with contradictory results. We have used the genotype instead of the phenotype (responsiveness to PROP or other tastants), to test the possible relation between genetic variability and the perception of wine characteristic in 528 subjects from Italy and the Czech Republic. We observed several interesting associations, among which the association between several TAS2R38 gene single nucleotide polymorphisms (P = 0.002) and the TAS2R16-rs6466849 polymorphism with wine sourness P = 0.0003). These associations were consistent in both populations, even though the country of origin was an important factor in the two models, thus indicating therefore that genetics alongside cultural factors also play a significant role in the individual liking of wine.

Perinatal morphine. I: Effects on synapsin and neurotransmitter systems in the brain

We have previously shown that rat perinatal exposure to morphine causes dopaminergic and met-enkephalin (ME) and substance P (SP) changes in the striatum during the early postnatal period (Tenconi et al.: Int J Dev Neurosci 10: 517 - 526, 1992); in addition it increases the susceptibility to neurotoxic lesions and impairs regenerative capacity of the serotoninergic system (Gorio et al.: J Neurosci Res 34: 462 - 471, 1993). Our study shows that ME and SP levels increase postnatally in several areas of the rat brain, reaching the highest values between 30 and 60 days, after which the peptide content subsides to lower levels. Perinatal exposure to morphine increases such ME and SP levels during the early stages of postnatal life. No effect of morphine on 5-HT and NE is observed, while the dopaminergic system is mainly affected in the mesencephalon. The pre- and postnatal brain expression of synapsin I mRNA is gradually and progressively localized in discrete areas of the brain. In the brain of rats perinatally exposed to morphine, the abundance of synapsin I mRNA expression is markedly reduced. Therefore, perinatal exposure to morphine affects early postnatal synaptic development in the brain as shown by the altered peptidergic and monoaminergic content and by the reduced synapsin I mRNA expression.

Perinatal morphine treatment inhibits pruning effect and regeneration of serotoninergic pathways following neonatal 5,7-HT lesions

Lesion of the serotoninergic system in neonate rats is an ideal model for assessing the activity of chemical substances capable of affecting neuronal plasticity and regeneration (Jonsson et al., Dev Brain Res 16: 171-180, 1984). Treatment of newborn rats within 6 hr from birth with the selective neurotoxin 5,7-dihydroxytryptamine causes degeneration of the most distal serotoninergic axons. In our experimental conditions we have observed that after such neurotoxic treatment there is spinal cord denervation, which is particularly remarkable in the lumbar segment. This degenerative event is followed by gradual regeneration of the lesioned axons, with good reinnervation of the entire cord within 8 weeks. The degeneration-regeneration process is correlated with a transient hyperinnervation of the pons-medulla and hypothalamus by the short collaterals (pruning effect), as evidenced by increased serotonin content. Perinatal morphine exposure markedly impairs serotonin regeneration in the spinal cord. In addition, opiate treated rats are more susceptible to lesions, as shown by the neurotoxin induced denervation of the cortex, pons-medulla, and hypothalamus, which does not occur in lesioned controls. Therefore, our observations suggest that perinatal exposure to morphine affects the plasticity and regeneration of the developing serotoninergic system by increasing its susceptibility to neurotoxic lesions and reducing its regenerative capacity.

Interaction of anthracycline antibiotics with human neutrophils: superoxide production, free radical formation and intracellular penetration

Human neutrophils exposed to 10(-4) M doxorubicin and the derivatives epirubicin and thepirubicin revealed a different intracellular penetration and distribution pattern as demonstrated by fluorescence microscopy and fluorimetric determination of drug intracellular concentration. While doxorubicin was found to be a potent inducer of superoxide generation from resting cells, epirubicin exhibited less superoxide-inducing power. Thepirubicin on the contrary did not show any superoxide-inducing effect. Moreover the anthracyclines tested all inhibited the phorbol ester-stimulated chemiluminescent response to the same extent, which suggested a common target for the drug action. Anthracycline-stimulated superoxide production seems to correlate with the cardiotoxic effects. The most cardiotoxic drug, doxorubicin, is the most potent inducer of superoxide generation, while epirubicin, which is less cardiotoxic, has a relatively limited effect on superoxide production. Thepirubicin which has been shown not to induce delayed cardiomyopathy has no effect on superoxide release from the cells.

Effect of inosine on guinea-pig bronchial muscle

Inosine, like other purine derivatives, shows antibronchospastic effects both in vivo and in vitro. Its activity remains in propranololor α-methyl-p-tyrosine-pretreated guinea-pigs, but is prevented by theophylline. Moreover, the interaction between 3′5AMP and inosine suggests potentiation. In view of recent findings showing that inosine inhibits phosphodiesterases, the conclusion is drawn that the antibronchospastic effect of this nucleoside depends on the increase of 3′5′AMP intracellular levels in the bronchial muscle.

Inhibiting effect of levamisole on superoxide production from rat mast cells

The aim of the present study was to test whether levamisole acts as a superoxide scavenger. The drug was incubated at four different concentrations (range 1, 5, 10, 20 micrograms/ml) with purified rat mast cells which were then induced to generate superoxide ions, by challenge with compound 48/80 (1 microgram/ml). Ten minutes preincubation with the drug completely abolished superoxide ions production. Addition of levamisole to the cell suspension simultaneously with the releaser caused full inhibition of O2(-) generation at the lowest dose, while higher doses failed to suppress 48/80 induced O2(-) generation. In a cell-free superoxide-generating system, like xanthine-xanthine oxidase, levamisole did not act as a superoxide scavenger at any of the doses tested.