Oleuropein Stimulates Migration of Human Trophoblast Cells and Expression of Invasion-Associated Markers

Successful pregnancy establishment requires highly synchronized cross talk between the invasive trophoblast cells and the receptive maternal endometrium. Any disturbances in this tightly regulated process may lead to pregnancy complications. Local factors such as nutrients, hormones, cytokines and reactive oxygen species modulate the invasion of extravillous trophoblasts through critical signaling cascades. Epidemiological studies strongly indicate that a Mediterranean diet can significantly impact molecular pathways during placentation. Therefore, the aim of the current study was to examine whether oleuropein (OLE), one of the main compounds of the Mediterranean diet, may influence trophoblast cell adhesion and migration, as well as the expression of invasion-associated molecular markers and inflammatory pathways fostering these processes. HTR-8/SVneo cells were incubated with OLE at selected concentrations of 10 and 100 µM for 24 h. Results showed that OLE did not affect trophoblast cell viability, proliferation and adhesion after 24 h in in vitro treatment. The mRNA expression of integrin subunits α1, α5 and β1, as well as matrix-degrading enzymes MMP-2 and -9, was significantly increased after treatment with 10 µM OLE. Furthermore, OLE at a concentration of 10 µM significantly increased the protein expression of integrin subunits α1 and β1. Also, OLE inhibited the activation of JNK and reduced the protein expression of COX-2. Finally, a lower concentration of OLE 10 µM significantly stimulated migration of HTR-8/SVneo cells. In conclusion, the obtained results demonstrate the effects of OLE on the function of trophoblast cells by promoting cell migration and stimulating the expression of invasion markers. As suggested from results, these effects may be mediated via inhibition of the JNK signaling pathway.

Oleuropein Attenuates Oxidative Stress in Human Trophoblast Cells

Olive-derived bioactive compound oleuropein was evaluated against damage induced by hydrogen peroxide in human trophoblast cells in vitro, by examining the changes in several markers implicated in oxidative stress interactions in the placenta. Trophoblast HTR-8/SVneo cells were preincubated with OLE at 10 and 100 µM and exposed to H₂O₂, as a model of oxidative stress. Protein and lipid peroxidation, as well as antioxidant enzymes' activity, were determined spectrophotometrically, and DNA damage was evaluated by comet assay. iNOS protein expression was assessed by Western blot, while the mRNA expression of pro- and anti-apoptotic genes BAX and BCL2 and transcription factor NFE2L2, as well as cytokines IL-6 and TNF α were determined by qPCR. Oleuropein demonstrated cytoprotective effects against H₂O₂ in trophoblast cells by significantly improving the antioxidant status and preventing protein and lipid damage, as well as reducing the iNOS levels. OLE reduced the mRNA expression of IL-6 and TNF α, however, it did not influence the expression of NFE2L2 or the BAX/BCL2 ratio after H₂O₂ exposure. Oleuropein per se did not lead to any adverse effects in HTR-8/SVneo cells under the described conditions, confirming its safety in vitro. In conclusion, it significantly attenuated oxidative damage and restored antioxidant functioning, confirming its protective role in trophoblast.

The Role of Dietary Polyphenols in Pregnancy and Pregnancy-Related Disorders

Polyphenols are a group of phytochemicals with extensive biological functions and health-promoting potential. These compounds are present in most foods of plant origin and their increased widespread availability through the intake of nutritional supplements, fortified foods, and beverages, has also led to increased exposure throughout gestation. In this narrative review, we focus on the role of polyphenols in both healthy and pathological pregnancy. General information related to their classification and function is followed by an overview of their known effects in early-pregnancy events, including the current insights into molecular mechanisms involved. Further, we provide an overview of their involvement in some of the most common pregnancy-associated pathological conditions, such as preeclampsia and gestational diabetes mellitus. Additionally, we also discuss the estimated possible risk of polyphenol consumption on pregnancy outcomes. The consumption of dietary polyphenols during pregnancy needs particular attention considering the possible effects of polyphenols on the mechanisms involved in maternal adaptation and fetal development. Further studies are strongly needed to unravel the in vivo effects of polyphenol metabolites during pregnancy, as well as their role on advanced maternal age, prenatal nutrition, and metabolic risk of the offspring.

IL-6 and IL-8: An Overview of Their Roles in Healthy and Pathological Pregnancies

Interleukin-6 (IL-6) is an acknowledged inflammatory cytokine with a pleiotropic action, mediating innate and adaptive immunity and multiple physiological processes, including protective and regenerative ones. IL-8 is a pro-inflammatory CXC chemokine with a primary function in attracting and activating neutrophils, but also implicated in a variety of other cellular processes. These two ILs are abundantly expressed at the feto-maternal interface over the course of a pregnancy and have been shown to participate in numerous pregnancy-related events. In this review, we summarize the literature data regarding their role in healthy and pathological pregnancies. The general information related to IL-6 and IL-8 functions is followed by an overview of their overall expression in cycling endometrium and at the feto-maternal interface. Further, we provide an overview of their involvement in pregnancy establishment and parturition. Finally, the implication of IL-6 and IL-8 in pregnancy-associated pathological conditions, such as pregnancy loss, preeclampsia, gestational diabetes mellitus and infection/inflammation is discussed.

Caffeic acid protects human trophoblast HTR-8/SVneo cells from H2O2-induced oxidative stress and genotoxicity

Caffeic acid is highlighted as one of the major phenolic compounds present in foods with known antioxidant activity. This phenolic is among commonly consumed substances in everyday diet of pregnant women. However, there is not enough information on its effects during pregnancy, especially the most vulnerable early stage. Extravillous trophoblast cells are specific cells of the placenta that come in direct contact with maternal uterine tissue. Through this study we investigated the cytoprotective effects of caffeic acid on H₂O₂-induced oxidative damage in first trimester extravillous trophoblast cell line HTR-8/SVneo. Investigated concentrations (1-100 μM) of caffeic acid showed neither cytotoxic nor genotoxic effects on HTR-8/SVneo cells. The treatment with caffeic acid 100 μM significantly increased the percentage of cells in G2/M phase of the cell cycle, compared to non-treated cells. Pretreatment with caffeic acid (10 and 100 μM) attenuated oxidative DNA damage significantly, reduced cytotoxicity, protein and lipid peroxidation, and restored antioxidant capacity in trophoblast cells following H₂O₂ exposure. This beneficial outcome is probably mediated by the augmentation of GSH and effective ROS scavenging by caffeic acid. These promising results require further investigations to reveal the additional mechanisms/pathways and confirmation through studies in vivo.

Galectins in Early Pregnancy and Pregnancy-Associated Pathologies

Galectins are a family of conserved soluble proteins defined by an affinity for β-galactoside structures present on various glycoconjugates. Over the past few decades, galectins have been recognized as important factors for successful implantation and maintenance of pregnancy. An increasing number of studies have demonstrated their involvement in trophoblast cell function and placental development. In addition, several lines of evidence suggest their important roles in feto-maternal immune tolerance regulation and angiogenesis. Changed or dysregulated galectin expression is also described in pregnancy-related disorders. Although the data regarding galectins' clinical relevance are still at an early stage, evidence suggests that some galectin family members are promising candidates for better understanding pregnancy-related pathologies, as well as predicting biomarkers. In this review, we aim to summarize current knowledge of galectins in early pregnancy as well as in pregnancy-related pathologies.

Strawberry (Fragaria ananassa duch.) Alba extract attenuates DNA damage in lymphocytes of patients with Alzheimer's disease

Increased levels of oxidative stress and oxidative DNA damage are common features in the pathology of Alzheimer's disease (AD) found in neurons and peripheral cells like peripheral blood lymphocytes (PBL). Natural products such as strawberry cultivar Alba are an important source of bioactive nutrients that could help in lowering both the oxidative stress and DNA damage levels. The objective was to estimate the effects of Alba extract on DNA damage in peripheral blood lymphocytes of sporadic AD (aged 60-84 years) patients, and healthy elderly (aged 69-83 years) and young (aged 21-30 years) individuals in in vitro conditions. Comet assay was used as a sensitive technique for the evaluation of PBL DNA damage levels. Reduction of basal DNA damage level in PBL was shown in the young group after the incubation with Alba extract ranging from 25 to 200 μg/ml, with 100 μg/ml being the most effective concentration. Selected Alba extract of 100 μg/ml was further used for PBL treatment of AD and healthy elderly age matched group, displaying potential to significantly attenuate DNA damage levels in both groups (p < .05). Alba extract displayed biological activity against oxidative DNA damage, suggesting that its functional ingredients may have beneficial health effects. PRACTICAL APPLICATIONS: The data obtained in this preliminary study displayed that strawberry Alba extract is efficient against DNA damage induced by endogenous and exogenous oxidative stress in peripheral blood lymphocytes of Alzheimer`s disease in vitro. An active area of future research of Alba cultivar should be to determine the trials in in vivo systems. Our findings also suggest that Alba cultivar's functional ingredients potentially may have beneficial health effects in AD.

Antigenotoxic properties of anthocyanin-enriched fraction of strawberry (cv. Romina) extract on DNA damage induced by H2O2 in human peripheral blood leukocytes

Strawberry fruit Fragaria × ananassa Duchesne, Rosaceae (cv. Romina), rich in anthocyanin polyphenols, has been demonstrated to have favorable effects on health due to its antioxidant properties. The present study investigated the antigenotoxic potential of anthocyanin enriched fraction of Romina strawberry methanolic extract (ACY) against DNA damage on human peripheral blood leukocytes, induced by hydrogen peroxide in vitro. Five concentrations of the ACY extract were used in all experiments (2.5, 5, 10, 15, 20 µg/ml). The results of the alkaline comet assay showed no genotoxic effect of the ACY. After the pre-exposure of the leukocytes to the ACY, and subsequent incubation with H2O2, a decreased number of DNA damaged cells was recorded in all the tested concentrations, compared to controls. In the posttreatment, there was a concentration-dependent DNA damage reduction, while a statistically significant decrease was achieved with 15 and 20 µg/ml concentrations. The results indicate that ACY is efficient in oxidative DNA damage reduction, and it is more potent as a post-applicative than a protective agent.

Standardized Olea europaea L. leaf extract exhibits protective activity in carbon tetrachloride-induced acute liver injury in rats: the insight into potential mechanisms

The protective activity of dry olive leaf extract (DOLE) in carbon tetrachloride (CCl₄)-induced liver damage and possible mechanisms involved in this protection were investigated in rats. Acute CCl₄ intoxication resulted in a massive hepatic necrosis, in increased serum transaminases, and in a perturbation of oxidative stress parameters in liver tissue [malondyaldehide, glutathione (GSH), catalase]. CCl₄ did not affect the expression of caspase-3 and cytochrome c as markers of apoptosis; however, CCl₄ increased the AMP-activated protein kinase (AMPK) activity and the expression of autophagy-related protein LC3II and decreased the expression of p62 protein. The pre-treatment with DOLE significantly improved serum markers of liver damage, liver catalase activity, and GSH concentration, suggesting that antioxidative mechanism is responsible for hepatoprotection. Oral administration of DOLE did not influence LC3II conversion and p62 degradation in liver, but AMPK activity was significantly decreased, suggesting the energy balance perturbation as an additional potential mechanism of DOLE hepatoprotective effect.

Olive leaf extract attenuates adriamycin-induced focal segmental glomerulosclerosis in spontaneously hypertensive rats via suppression of oxidative stress, hyperlipidemia, and fibrosis

Olive (Olea europaea L.) leaf extract (OLE) possesses powerful antioxidant, antihyperlipidemic, and anti-inflammatory properties. The aim was to investigated the effects of OLE on the hyperlipidemia, antioxidant defense, heme oxygenase/biliverdin reductase (HO/BVR) pathway, inflammation, and fibrosis in spontaneously hypertensive rats with focal segmental glomerulosclerosis (FSGS, a progressive form of chronic kidney disease) induced by adriamycin (2 mg/kg, i.v., twice in a 21-day period). Daily treatment of OLE (80 mg/kg, p.o.) for 6 weeks suppressed protein oxidation and lipid peroxidation (p < .01 and p < .001, respectively), significantly increased antioxidant enzymes activities and normalized antioxidant capacity, leading to the improvement of antioxidant defense independently of the HO/BVR pathway. Furthermore, the values of triglycerides (p < .01), total, and low-density lipoprotein cholesterol (p < .05, both) were improved by OLE. OLE strongly prevented glomerulosclerosis, interstitial inflammation, and fibrosis (renal injury score, FSGS: 8 ± 0.45 vs. FSGS+OLE: 4.20 ± 1.07; p < .01), as evidenced by normalized fibronectin content (p < .001), suppressed interstitial inflammatory cells infiltration and collagen deposition, without changing cytokines expressions. OLE decreased blood pressure with a tendency to reduce urine albumin loss. These data suggest that OLE may be effective in slowing down the progression of FSGS.

P0916OLIVE LEAF EXTRACT IMPROVES RENAL ANTIOXIDANT DEFENSE WITHOUT ALTERING THE HEME OXYGENASE-1/BILIVERDIN REDUCTASE PATHWAY IN HYPERTENSIVE RATS WITH FOCAL SEGMENTAL GLOMERULOSCLEROSIS

Background and Aims

Oxidative stress is implicated in the pathophysiology of chronic kidney disease. Previously, we showed that adriamycin (anticancer agent, enhances reactive oxygen species production) induced focal segmental glomerular sclerosis (FSGS) with massive proteinuria in spontaneously hypertensive rats (SHR). The heme oxygenase (HO) system plays an important role in regulating oxidative stress and is protective in chronic kidney disease. HO-1 is a cytoprotective enzyme that catalyzes the conversion of highly reactive free heme molecules into biliverdin, carbon monoxide, and iron. Biliverdin is subsequently converted to bilirubin by biliverdin reductase and has potent antioxidant effect. Olive leaf extract (OLE, Olea europaea L.) is rich in phenolic compounds that are known to possess powerful antioxidant properties. Here, we aimed to investigate the effects of OLE, focusing on its modulatory role on oxidative stress and HO-1/BVR pathway in the kidney of SHR with adriamycin-induced FSGS.

Method

Adult females SHR were divided into three groups. Control rats received vehicle. Two other groups, FSGS and FSGS+OLE, received adriamycin (2 mg/kg body weight i.v.) twice in 3-week-interval. After the second injection, FSGS+OLE group received OLE (80 mg/kg/day) by gavage for 6 weeks. Mean blood pressure (MAP), urine albumin-to-creatinine (Ualb/cr), renal HO-1 and biliverdin reductase protein expressions (Western Blot), protein carbonyl content (PCOs), and antioxidant capacity (ABTS) were analyzed.

Results

In FSGS group albuminuria was significantly increased in comparison to the level in control. Chronic consumption of OLE markedly, but not significantly decreased Ualb/cr compared to that in control. Analysis of renal PCOs revealed that significant enhancement of protein oxidation in the kidney of model group was reduced after OLE treatment to the level as in control. The ABTS level in kidney homogenates significantly decreased in FSGS group in comparison to the level in control. OLE significantly increased renal antioxidant capacity in FSGS+OLE group compared to that in model group. Western blot analysis of HO-1, and biliverdin reductase in the kidney revealed that protein expressions of both enzymes were significantly decreased in FSGS group compared to that in control. Following OLE treatment in FSGS+OLE group protein expressions of HO-1, and biliverdin reductase remained at similar level as in model group. No change in MAP values were observed between control and model groups. OLE significantly decreased MAP in FSGS+OLE group in comparison to the value of model group, and nearly significant reduction of MAP compared to the value of control.

Conclusion

Collectively, our results showed that OLE expressed its antioxidant property and improved oxidative status in the kidney of SHR with ADR-induced FSGS, independently of the HO-1/BVR pathway.

Dry olive leaf extract attenuates DNA damage induced by estradiol and diethylstilbestrol in human peripheral blood cells in vitro

Phenolic groups of steroidal or nonsteroidal estrogens can redox cycle, leading to oxidative stress, where creation of reactive oxygen species are recognized as the main mechanism of their DNA damage properties. Dry olive (Olea europaea L.) leaf extract is known to contain bioactive and antioxidative components and to have an ability to modulate the effects of various oxidants in cells. The main goal of this study was to investigate antigenotoxic potential of a standardized dry olive leaf extract on DNA damage induced by 17β-estradiol and diethylstilbestrol in human whole blood cells in vitro, using comet assay. Our results indicated that both hormones showed a genotoxic effect at a concentration of 100 μM (P < 0.05, n = 6). Dry olive leaf extract was efficient in reducing number of cells with estrogen-induced DNA damage at tested concentrations (0.125, 0.5 and 1 mg/mL) (P < 0.05, n = 6) and under two experimental protocols, pre-treatment and post-treatment, exhibiting antigenotoxic properties. Analysis of antioxidant properties of the extract revealed moderate ABTS radical scavenging properties and reducing power. Overall, our results suggested that the protective potential of dry olive leaf extract could arise from the synergistic effect of its scavenging activity and enhancement of the cells' antioxidant capacity.

Highly potent antioxidant Olea europaea L. leaf extract affects carotid and renal haemodynamics in experimental hypertension: The role of oleuropein

Haemodynamic alterations in carotid and renal arteries are associated with the severity of target organ damage in patients with hypertension. Dietary habits, such as the Mediterranean diet, regulate blood pressure and oxidative stress, thus reduce the mortality rate due to cardiovascular diseases. In this study, our aim was to evaluate the reducing activity, antioxidant capacity and metal chelating ability of standardized Olea europaea L. leaf extract (OLE), and to test its (5, 25, 50 mg/kg) acute in vivo effects, as well as oleuropein's (OP, 10 mg/kg) on oxidative stress, carotid, renal and systemic haemodynamic parameters (blood pressure, heart rate, cardiac output, peripheral resistance) in spontaneously hypertensive rats (SHR). OLE has a higher antioxidative capacity than BHT, higher reducing ability than vitamin C, and 23 times lower capacity for metal ion chelation than EDTA. All three doses of OLE, and OP, improved oxidative stress in SHR. OLE5 improved carotid and renal haemodynamics, without significant effects on systemic haemodynamics. Two different mechanisms of antihypertensive responses to OLE were observed, OLE25 was most effective in reducing cardiovascular risks by improving systemic and regional (carotid and renal) haemodynamics, peripheral and regional vascular resistance. OLE50 causes the improvement of blood pressure and cardiac performances, but tends to retain elevated vascular resistance, therefore, reducing the inflow of blood into the brain and kidneys of the SHR. The OP did not alter systemic or regional haemodynamics, suggesting others constituents responsible for changes of cardiac function, as well as carotid and renal haemodynamics in response to OLE50.

Protective effect of olive leaf extract on hippocampal injury induced by transient global cerebral ischemia and reperfusion in Mongolian gerbils

The beneficial effects of antioxidant nutrients, as well as complex plant extracts, in cerebral ischemia/reperfusion brain injury are well known. Mediterranean diet, rich in olive products, is associated with lower incidence of cardiovascular disease, cancer, inflammation and stroke. In this study, the possible neuroprotective effect of standardized dry olive leaf extract (OLE) is investigated for the first time. Transient global cerebral ischemia in Mongolian gerbils was used to investigate the OLE effects on different parameters of oxidative stress and neuronal damage in hippocampus. The biochemical measurements took place at different time points (80min, 2, 4 and 24h) after reperfusion. The effects of applied OLE were compared with effects of quercetin, a known neuroprotective plant flavonoid. Pretreatment with OLE (100mg/kg, per os) significantly inhibited production of superoxide and nitric oxide, decreased lipid peroxidation, and increased superoxide dismutase activity in all time points examined. Furthermore, OLE offered histological improvement as seen by decreasing neuronal damage in CA1 region of hippocampus. The effects of applied OLE were significantly higher than effects of quercetin (100mg/kg, per os). Our results indicate that OLE exerts a potent neuroprotective activity against neuronal damage in hippocampus after transient global cerebral ischemia, which could be attributed to its antioxidative properties.

Dry olive leaf extract ameliorates experimental autoimmune encephalomyelitis

BACKGROUND & AIMS

Experimental autoimmune encephalomyelitis (EAE) is an animal model of CNS inflammatory and demyelinating disease multiple sclerosis. Mediterranean diet, rich in olive products is associated with lower incidence of multiple sclerosis in South European population. Therefore, the influence of dry olive leaf extract (DOLE) on EAE course was investigated.

METHODS

Spinal cord homogenate and complete Freund's adjuvant were used for the induction of EAE in Dark Agouti rats. DOLE was applied intragastrically once per day, starting from the day of the immunization. Real time PCR and ELISA were used for the determination of IFN-gamma and IL-17 gene expression and production, respectively.

RESULTS

DOLE reduced various parameters of EAE severity in DA rats, including cumulative disease index, maximal clinical score and disease duration. Also, DOLE decreased cellularity of the draining lymph nodes and production of IFN-gamma and IL-17 by the cells infiltrating spinal cord of EAE rats.

CONCLUSIONS

The results presented in this paper strongly suggest that DOLE-enriched diet has a beneficial effect in EAE in rats. Further studies in humans are required in order to investigate if DOLE could be a useful supplementary dietetic for the patients suffering from multiple sclerosis and other neuroinflammatory disorders.

Attenuation of cold restraint stress-induced gastric lesions by an olive leaf extract

Olive leaf extract (OLE) possesses, among other, antioxidative properties, but whether it influences gastroprotection against stress-induced gastric lesions remains unknown. In this study we investigated the protective effect of OLE, a natural antioxidant, on gastric mucosal damage induced by cold restraint stress (CRS) in rats. Three different doses of commercial OLE EFLA((R)) 943 were applied intragastrically (i.g.) 30 min prior to stress induction. Macroscopic gastric lesions were evaluated and ulcer index (UI) was calculated. Histological evidence of gastric mucosal lesions was also obtained. Concentration of malondialdehyde (MDA) as an index of lipid peroxidation, and catalase (CAT) and superoxide dismutase (SOD) activities were determined in gastric mucosa. The effects of applied OLE on gastric mucosal lesions, lipid peroxidation and antioxidative enzymes activity were compared with effects of i.g. pretreatment of reference drug, ranitidine. CRS caused severe gastric lesions in all non-pretreated animals, and this finding was confirmed histologicaly. Pretreatment with OLE (40, 80 and 120 mg.kg(-1)), as well as with ranitidine (50 mg.kg(-1)), significantly (p < 0.001) attenuated stress-induced gastric lesions. Treatment with 80 mg.kg(-1) of OLE was the most effective in prevention of rise in gastric MDA level and decrease in CAT and SOD activity. The results obtained indicate that OLE possesses gastroprotective activity against CRS-induced gastric lesions in rats, possibly related to its antioxidative properties.

Mechanism of 3-deazaguanine transport in the rat heart

The aim of this study was to determine the mechanism of transport of 3-deazaguanine in the rat heart. We used single-pass, paired-tracer dilution method on isolated and retrogradely perfused rat hearts. The maximal cellular uptake (Umax) and total cellular uptake (Utot) of 3-deazaguanine were determined under control conditions and under influence of possible modifiers. Both Umax and Utot were significantly reduced in the presence of unlabeled 3-deazaguanine (from 19.57 +/- 2.02% to 8.14 +/- 1.19% and from 16.49 +/- 3.65% to 4.70 +/- 1.96%, n=6, respectively). The presence of pyrimidine nucleoside thymidine caused the reduction of both Umax and Utot (from 20.03 +/- 3.76% to 13.58 +/- 3.16% and from 16.43 +/- 3.58% to 11.94 +/- 3.13%, n=6, respectively). Also, we tested the effect of the absence of sodium ions in perfusion solution (both Umax and Utot, significantly reduced from 17.95 +/- 2.73% to 16.67 +/- 2.16% and from 16.68 +/- 2.97% to 14.81 +/- 3.04%, n=6, respectively) and the effect of dinitrophenol (both Umax and Utot significantly reduced from 19.09 +/- 3.68% to 10.58 +/- 3.14% and from 16.86 +/- 3.84% to 7.10 +/- 3.11%, n=6, respectively). The results of self- and cross-inhibition studies show that the transport of 3-deazaguanine is saturable, energy- and sodium-dependent and that 3-deazaguanine uses endogenous transport systems for thymidine and adenosine for its own transport.

Transport of endogenous nucleosides in guinea pig heart

The purpose of this study was to investigate the characteristics of transport of endogenous nucleosides into cardiac tissue from coronary circulation. The study was performed on the isolated perfused guinea pig heart, using the rapid paired tracers single-pass technique. The maximal cellular uptake (Umax) and total cellular uptake (Utot) of adenosine, deoxyadenosine, thymidine, uridine, and cytidine were determined. The cellular uptake of adenosine was significantly higher than the cellular uptake of other studied nucleosides. To elucidate the mechanisms of nucleoside transport, competition studies were performed and the influence of S-(p-nitrobenzyl)-6-thioinosine (NBTI) and sodium ion absence on Umax and Utot was investigated. Self- and cross-inhibition studies indicated the saturable mechanism of nucleosides transport into cardiac tissue and the involvement of different transport mechanisms for purine and pyrimidine nucleosides. The study also showed that both equilibrative-sensitive (es) and sodium-dependent transport were responsible for adenosine and thymidine cellular uptake.Key words: nucleosides, transport, heart.