Redox Biomarkers Assessment after Oral Administration of Wine Extract and Grape Stem Extract in Rats and Mice.

Wine and by-products of the winemaking process, such as grape stems, are rich in bioactive polyphenolic compounds that might be beneficial for animal and human health. In recent years, the administration of dietary polyphenols with strong antioxidant and cytoprotective properties has constituted an emerging line of research interest toward disease prevention. However, in scientific literature, only a limited number of studies have investigated the safety and the toxicological risks of polyphenolic compounds in vivo. Based on the above, the purpose of the present study was two-fold: first, to examine the effects of oral administration of a grape stem extract, derived from the Greek red wine Mavrodaphne, on mice redox biomarkers; and second, to investigate the biological effects of oral administration of a wine extract, derived from the emblematic Greek red wine Xinomavro, on rats. Toward this purpose, body weight, growth rate, hematological, biochemical, and histopathological parameters, as well as a panel of redox biomarkers, were examined. According to our results, the administration of Mavrodaphne grape stem extract in mice induced alterations in redox homeostasis, preventing mice from the adverse effects of lipid peroxidation. Contrariwise, the administration of Xinomavro wine extract induced both beneficial and harmful outcomes on rat redox status determined by the examined tissue. Collectively, our study reports that the Mavrodaphne grape stem extract, a serious pollutant when disposed in environmental matrices, is an important source of bioactive polyphenolic compounds that could protect from oxidative damage and improve animal and human health. Finally, the Xinomavro wine extract exerts tissue-specific changes in redox balance, which are indicative of the complexity that characterizes the biological systems.

Self-Nanoemulsifying Drug Delivery Systems (SNEDDS) Containing Rice Bran Oil for Enhanced Fenofibrate Oral Delivery: In Vitro Digestion, Ex Vivo Permeability, and In Vivo Bioavailability Studies.

Lipid-based drug delivery systems (LbDDS), such as self-nanoemulsifying drug delivery systems (SNEDDS), constitute a prominent formulation approach for enhancing the aqueous solubility and oral bioavailability of poorly water-soluble compounds. Utilization of biorefinery wastes, such as oil from rice bran, may prove advantageous to both improving drug solubilization and absorption and to achieving sustainable agri-food waste valorization. Here, we assessed the effect of four SNEDDS compositions differing in the oil (rice bran oil and corn oil) and surfactant type (Kolliphor RH40 and EL) on the oral bioavailability of fenofibrate, a BCS class II compound. Prior to the in vivo oral administration of the SNEDDS in rats, drug solubilization was tested in vitro using the static digestion model, followed by the ex vivo permeability study of the predigested SNEDDS using the non-everted gut sac model. No significant variation was observed in the solubilization capacity within the different SNEDDS formulations. On the other hand, the ex vivo permeability data of the predigested SNEDDS correlated well with the in vivo bioavailability data designating the superiority of rice bran oil with Kolliphor EL as the surfactant, to enhance the oral absorption of fenofibrate. Results indicated that valorization of agro-industrial waste such as rice bran oil may prove useful in enhancing the oral performance of LbDDS in the case of fenofibrate, while at the same time maximizing the use of agricultural by-products via the creation of new sustainable value chains in the pharmaceutical field.

A mixture of routinely encountered xenobiotics induces both redox adaptations and perturbations in blood and tissues of rats after a long-term low-dose exposure regimen: The time and dose issue.

Exposure of humans to xenobiotic mixtures is a continuous state during their everyday routine. However, the majority of toxicological studies assess the in vivo effects of individual substances rather than mixtures. Therefore, our main objective was to evaluate the impact of the 12- and 18-month exposure of rats to a mixture containing 13 pesticides, food, and life-style additives in three dosage levels (i.e. 0.0025 × NOAEL, 0.01 × NOAEL, and 0.05 × NOAEL), on redox biomarkers in blood and tissues. Our results indicate that the exposure to the mixture induces physiological adaptations by enhancing the blood antioxidant mechanism (i.e., increased glutathione, catalase and total antioxidant capacity and decreased protein carbonyls and TBARS) at 12 months of exposure. On the contrary, exposure to the 0.05 × NOAEL dose for 18 months induces significant perturbations in blood and tissue redox profile (i.e., increased carbonyls and TBARS). This study simulates a scenario of real-life risk exposure to mixtures of xenobiotics through a long-term low-dose administration regimen in rats. The results obtained could support, at least in part, the necessity of introducing testing of combined stimuli at reference doses and long term for the evaluation of the risk from exposure to chemicals.

A lightly roasted coffee extract improves blood and tissue redox status in rats through enhancement of GSH biosynthesis.

Coffee is a highly consumed beverage with many putative beneficial health effects, however these often come from observational studies. In the current work, a lightly roasted coffee extract that has previously been reported to exhibit potent antioxidant properties was administered for two weeks in rats to examine the potential improvement of blood and tissue redox status. The dose was equivalent to a moderate human daily consumption. According to our results, coffee exerted beneficial effects in all tissues mainly by increasing reduced glutathione (GSH) levels. Interestingly, the brain was the most significantly affected tissue, while the gastrointestinal tract, the main metabolic organs and the quadriceps were also benefited. In addition, protein and lipid oxidation was reduced in several tissues. The observed increase in GSH was attributed to increased levels of the rate-limiting enzyme in its biosynthesis pathway, namely γ-glutamylcysteine ligase both in the protein and gene levels. Overall, moderate coffee consumption showed beneficial short term effects in rat tissues by stimulating parts of the endogenous antioxidant mechanisms.

Silver Nanoparticles Alter Cell Adhesion and Proliferation of Sheep Primary Mesothelial Cells.

BACKGROUND: Human exposure to engineered nanoparticles has been linked to pleural effusion, inflammation and fibrosis. Silver nanoparticles (AgNPs) are widely used in medical and domestic products, increasing the risk of occupational and domestic exposure. We assessed the influence of AgNPs on adhesion and proliferation of sheep primary pleural mesothelial cells. MATERIALS AND METHODS: Cells were used for cell adhesion (90 min) and proliferation experiments (3 days) while exposed to 20 nm and 60 nm AgNPs (0.2 µg/ml and 2 µg/ml) using colorimetric assays. RESULTS: Exposure to 0.2 µg/ml of 20 nm and 60 nm AgNPs significantly increased cell adhesion, while at 2 µg/ml this effect was not elicited. Cell proliferation was significantly increased by both 20 nm and 60 nm AgNPs at 0.2 µg/ml, while at 2 µg/ml this effect was only elicited by the 60 nm AgNPs. CONCLUSION: AgNPs alter the adhesive and proliferative properties of primary pleural mesothelial cells.

Silver nanoparticles alter the permeability of sheep pleura and of sheep and human pleural mesothelial cell monolayers.

Nanoparticles have been implicated in the development of pleural effusions in exposed factory workers while in experimental animal studies it has been shown that they induce inflammation, fibrosis and carcinogenesis in the pleura. The scope of this study was to investigate the direct effects of silver nanoparticles exposure on the membrane permeability of sheep parietal pleura, of primary sheep pleural cell monolayers and on a human mesothelial cell line. Our findings suggest that acute (30min) exposure increases the pleural permeability ex vivo, while longer (24h) exposure in vivo leads to late decrease of the pleural cell monolayers permeability.

Antioxidant effect of a polyphenol-rich grape pomace extract on motility, viability and lipid peroxidation of thawed bovine spermatozoa.

BACKGROUND: Grape extracts of the Greek species Vitis vinifera possess potent antioxidant properties in vitro. The freeze/thaw process and the preparation of semen during assisted reproductive techniques can adversely affect the functional integrity of spermatozoa. The objective was to assess the effect of three different concentrations (1 µg ml(-1), 2 µg ml(-1) and 5 µg ml(-1)) of a polyphenol-rich grape pomace extract on motility, viability, acrosomal and lipid peroxidation status of thawed bovine spermatozoa after 2 and 4 hrs of incubation. RESULTS: The results indicate that the percentage of "Rapid" spermatozoa remained significantly increased (p <0.05) in the presence of 5 µg ml(-1) of the extract, compared to the control after 2 hrs of incubation. Additionally, the incubation of spermatozoa with 2 µg ml(-1) and 5 µg ml(-1) of the extract for 2 hrs resulted in a significantly better maintenance of viable spermatozoa with intact acrosome (p <0.05). The other parameters did not show statistically significant changes. Moreover, the presence of 2 µg ml(-1) and 5 µg ml(-1) of the extract kept the levels of Malondialdehyde (MDA) production in significantly lower level, compared to the other groups, after 2 hrs and 4 hrs of incubation (p <0.05). Particularly, a dose-dependent effect was noticed after 2 hrs of incubation. CONCLUSIONS: Our results suggest that the grape pomace extract exerts a powerful antioxidant role, by suppressing lipid peroxidation, and provides protection in terms of motility and acrosomal integrity, which are correlated with in vivo fertility. The optimal extract concentration is 5 µg ml(-1).

CCl4 induces tissue-type plasminogen activator in rat brain; protective effects of oregano, rosemary or vitamin E.

The high metabolic rate and relatively low antioxidant defenses of the lipid-rich brain tissue render it highly susceptible to reactive oxygen species (ROS) and oxidative stress, whereas the implication of ROS in the pathogenesis of several diseases in the central nervous system is well-established. The plasminogen activator (PA) system is a key modulator of extracellular proteolysis, extracellular matrix remodeling and neuronal cell signaling and has been implicated in the pathogenesis of these diseases. This study evaluates the role of tissue-type PA (t-PA) in oxidative stress and the protective role of dietary antioxidants in the rat brain. We used the CCl4 experimental model of ROS-induced lipid peroxidation and evaluated the antioxidant effect of oregano, rosemary or vitamin E. CCl4-treated Wistar rats exhibited elevated brain t-PA activity, which was decreased upon long-term administration of oregano, rosemary or vitamin E. PA inhibitor-1 (PAI-1) activity was also slightly elevated by CCl4, but this increase was not affected by the antioxidants. We hypothesize that the CCl4-induced t-PA activity indicates extracellular proteolytic activity that may be linked to neuronal cell death and brain damage. Vitamin E or antioxidants present in oregano or rosemary are effective in inhibiting t-PA elevation and can be considered as a potential protection against neuronal damage.

Endosulfan-induced lipid peroxidation in rat brain and its effect on t-PA and PAI-1: ameliorating effect of vitamins C and E.

Endosulfan provokes systemic toxicity in mammals and induces reactive oxygen species (ROS) and lipid peroxidation (LPO). The brain is susceptible to LPO and several studies implicate ROS and LPO in CNS diseases. Tissue plasminogen activator (t-PA) has been accredited with plasminogen-dependent roles in the CNS, as well as plasminogen-independent functions. The aim of this study was to investigate the activities of t-PA and its inhibitor, plasminogen activator inhibitor-1 (PAI-1) in the adult rat brain, after subchronic endosulfan treatment. Furthermore, the potency of vitamins C and E to attenuate these effects was explored. Endosulfan was administered in Wistar rats either alone or with vitamin C and/or vitamin E. The induced oxidative stress was manifested by induction of LPO as determined by higher malondialdehyde levels. This was accompanied by elevation of t-PA and PAI-1 activities. Vitamins E and C, both well-known for their antioxidant properties, substantially acted in a preventive way and protected the brain from these effects.

Toxoplasma gondii: reproductive parameters in experimentally infected male rats.

Toxoplasma gondii is a protozoan parasite that is globally widespread and infects man and animals. With the aim of studying the influence of toxoplasmosis on male reproductive parameters, we investigated sperm motility, concentration and morphology of male rats experimentally infected by T. gondii. The GT F1 strain of T. gondii tissue cysts were fed at a dose of 5 x 10(3) tissue cysts per rat by oral gavage in an experimental group of 42 healthy adult male Wistar rats, while 42 male rats were used as controls. On days 10, 20, 30, 40, 50 and 60 post-inoculation (p.i.) 7 rats from each group were anesthetized. The body weight of each animal was recorded, then epididymis and testes were immediately removed, weighed and semen evaluation was undertaken. Weight of the right epididymis was significantly decreased on day 30 p.i., sperm motility was significantly decreased on days 10, 20, 30, 40, 50 and 60 p.i. and sperm concentration was significantly decreased on days 10, 30, 40 and 60 p.i. A marked increase of sperm abnormalities was noticed on days 30 and 40 p.i. No pathological lesions were detected either in the pituitary gland or the testes. In this study it was found that toxoplasmosis can affect main reproductive parameters in male rats, which are the most predictive of their fertilizing capacity.

Modifications of surface carbohydrates on bovine spermatozoa mediated by oviductal fluid: a flow cytometric study using lectins.

The objective of the present study was to characterize and quantify changes in exposed saccharide residues of bovine sperm during capacitation in oviductal fluid (ODF) using flow cytometry (FC). Bovine sperm were incubated with 0% or 50% non-luteal ODF for 30 min or 3.5 h. After incubation, sperm were labelled with 11 fluorescein isothiocyanate-labelled lectins and evaluated for lectin binding with FC. Furthermore, inhibiting sugars were used to determine specificity of lectin binding to oligosaccharides on the sperm surface. After 30 min incubation, there was a 91% decrease in fluorescence intensity of labelled sperm incubated in WGA, a 76% decline for Con A, 75% decline for BS-I and a 36% decline for DBA. These differences remained approximately the same over the 3.5-h incubation. Interestingly, although there was no reduction in UEA-I binding at 30 min, a significant reduction (23%) was observed at 3.5 h. Con A fluorescence was mostly inhibited with either alpha-d-glucose or alpha-d-mannose (86% and 90% respectively). BS-I fluorescence was reduced after prior incubation of the control samples with N-acetyl-galactosamine and galactose by 74% and 80% respectively. After prior incubation with N-acetyl-galactosamine DBA fluorescence reduced by 18% in the control samples. With UEA-I no fluorescence reduction was observed after prior incubation with l-fucose. We have demonstrated that capacitation of bovine sperm in ODF is accompanied by a quantitative reduction in individual lectin binding sites. These modifications may be crucial to the subsequent signalling events involved with sperm-zona binding, zona penetration or interaction with the oolema.

Plasminogen activator activity in the porcine oviduct during the oestrous cycle.

The mammalian oviduct is a dynamic tissue, which lies under the influence of ovarian steroids and produces proteins that affect various stages of fertilization and post-fertilization events. In this study, expression of urokinase-type plasminogen activator (u-PA mRNA) and plasminogen activator activity (PAA) were examined in porcine oviducts by reverse transcription and polymerase chain reaction (RT-PCR) and activity assays, respectively. For this purpose, oviducts were collected from Landrace cycling sows and divided into three segments (isthmus, ampulla, infundibulum). Different concentrations of u-PA mRNA were detected in the three segments following the pattern isthmus>ampulla>infundibulum and this pattern was maintained during the oestrous cycle. On the contrary, the highest PAA was measured in the ampulla compared to the isthmus and the infundibulum and the highest ampullary PAA was detected during the first 2 days of the oestrous cycle. The different regulation of u-PA mRNA expression and PAA is probably due to the existence of PA inhibitors. Recent observations suggest that PAI-1, the main inhibitor of PAs, shows greater expression in the isthmus compared to the ampulla and the local generation of plasmin is inhibited. The latter may be related to observations that spermatozoa are quiescent in the isthmus before fertilization. This study supports the suggestion that urokinase-type plasminogen activator has a biological role within the porcine oviduct, especially at or near the time of fertilization.

Effect of plasmin on movement characteristics of ejaculated bull spermatozoa.

Proteolytic enzymes appear to have an essential role in multiple phases of mammalian fertilization. Several observations suggest that the plasminogen activator/plasmin system might also play a role in mammalian fertilization. Movement characteristics of bovine sperm incubated with different concentrations of plasmin were investigated using a computer-assisted automated semen analysis system. Sperm were incubated up to 4h in a modified Tyrode's medium (control) and 0.1, 1, 10 and 100 mU/ml of plasmin. The percentage motile sperm was significantly higher at 0 h for sperm incubated in 1, 10, and 100 mU of plasmin. Relative to sperm incubated in control medium, lateral head displacement (ALH), curvilinear velocity, beat cross frequency, path velocity and straight line velocity (VSL) of sperm treated with 100 mU of plasmin for 0 h were increased. After 2h of incubation, sperm treated with 100 mU of plasmin showed an increase in ALH, but a decrease in VSL, straightness and linearity. The effect of plasmin on most motility parameters appears to be direct since all these parameters were affected at 0 h of incubation. Our results support the notion of hyperactivation of bovine spermatozoa following incubation with different concentrations of plasmin. The present work provides additional information to further characterize motility movement of bovine sperm associated with final preparation for fertilization.