Use of high polyphenols grape seeds cakes to modulate the inflammatory status and piglet health during the post-weaning period

Weaning is a very difficult period for the pig, during which the nature and quality of the feeds is of great influence on the developing systems of digestion and defence. The weaning time is correlated with an increase of local inflammatory response. The supplementation of the weaning diet with ingredients rich in bioactive compounds with antimicrobial properties was lately investigated. This is the case of the polyphenols, which have been studied in depth for their beneficial effect on health and for their antioxidant action, but to a lesser extent, for their antimicrobial action. Grape by-products (grape seeds, grape pomace) could be alternative and cheaper sources with anti-microbial potential which could be used in the weaning diet. In the present study we analysed the effects of 5% grape seed cakes (GS) inclusion in the diet on the blood biochemical parameters and on pro- and anti-inflammatory markers in spleen and lymph nodes. A total of 12 weaned pigs were fed with a control or 5% grape seed cakes (GS) diets for 30 days. Pigs were sacrificed after 30 days, blood and organs were collected and stored at –80°C until analyses. Our results showed that diet included 5% GS did not influence the health status determined by plasma biochemical parameters. Only a tendency for a slight increase of the biochemical parameters associated with energetic profile (glucose, cholesterol, triglycerides) was observed Also, GS diet had no effect on pro- and anti-inflammatory cytokines content in spleen and lymph nodes tissue. Further experiments are needed in order to investigate other rate of dietary inclusion which could provide more evidence about the effect of grape bioactive compounds on general health status and inflammation in weaning piglets

Regulated mitochondrial DNA replication during oocyte maturation is essential for successful porcine embryonic development.

Cellular ATP is mainly generated through mitochondrial oxidative phosphorylation, which is dependent on mitochondrial DNA (mtDNA). We have previously demonstrated the importance of oocyte mtDNA for porcine and human fertilization. However, the role of nuclear-encoded mitochondrial replication factors during oocyte and embryo development is not yet understood. We have analyzed two key factors, mitochondrial transcription factor A (TFAM) and polymerase gamma (POLG), to determine their role in oocyte and early embryo development. Competent and incompetent oocytes, as determined by brilliant cresyl blue (BCB) dye, were assessed intermittently during the maturation process for TFAM and POLG mRNA using real-time RT-PCR, for TFAM and POLG protein using immunocytochemistry, and for mtDNA copy number using real-time PCR. Analysis was also carried out following treatment of maturing oocytes with the mtDNA replication inhibitor, 2',3'-dideoxycytidine (ddC). Following in vitro fertilization, preimplantation embryos were also analyzed. Despite increased levels of TFAM and POLG mRNA and protein at the four-cell stage, no increase in mtDNA copy number was observed in early preimplantation development. To compensate for this, mtDNA appeared to be replicated during oocyte maturation. However, significant differences in nuclear-encoded regulatory protein expression were observed between BCB(+) and BCB(-) oocytes and between untreated oocytes and those treated with ddC. These changes resulted in delayed mtDNA replication, which correlated to reduced fertilization and embryonic development. We therefore conclude that adherence to the regulation of the timing of mtDNA replication during oocyte maturation is essential for successful embryonic development

Food Contaminant Zearalenone and Its Metabolites Affect Cytokine Synthesis and Intestinal Epithelial Integrity of Porcine Cells

The intestinal epithelium is the first barrier against food contaminants. Zearalenone (ZEN) is an estrogenic mycotoxin that was identified as a common contaminant of cereal grains and food and feedstuffs. In the present study, we have investigated the in vitro effects of ZEN and some of its metabolites (α-ZOL, β-ZOL) in concentrations of 10–100 µM on a swine epithelial cell line: Intestinal porcine epithelial cells (IPEC-1). We demonstrated that both ZEN metabolites were more toxic for IPEC cells as resulted from the XTT test, while for doses lower than 10 µM, only β-ZOL showed a more pronounced cytotoxicity versus epithelial cells as resulted from neutral red assay. ZEN has no effect on TER values, while α-ZOL significantly decreased the TER values, starting with day 4 of treatment. β-ZOL had a dual effect, firstly it induced a significant increase of TER, and then, starting on day 6, it induced a dramatic decrease of TER values as compared with on day 0. Concerning the cytokine synthesis, our results showed that ZEN has a tendency to increase the synthesis of IL-8 and IL-10. By contrast, α- and β-ZOL decreased the expression of both IL-8 and IL-10, in a dose dependent manner. In conclusion, our results showed that ZEN and its metabolites differently affected porcine intestinal cell viability, transepithelial resistance and cytokine synthesis with important implication for gut health

Effect of Ochratoxin A and Aristolochic Acid on a Porcine Kidney Cell Line

The Balkan endemic nephropathy (BEN) is an irreversible, chronic, tubulo-interstitial nephropathy described so far in several rural regions from the Balkan with an unknown aetiology. Both ochratoxin A (OTA) and aristolochic acid (AA) are considered responsible for BEN. This paper performed a comparison between the toxic effect of OTA and AA using a kidney cell line LLC-PK. OTA and AA decreased cell viability in a dose dependent manner. The dose dependent effect was observed for both toxins, the doses higher than 5mg/mL inducing a significant inhibition of viability (P<0.05) in AA and OTA treated cells, when compared with control. For doses higher than 50mg/mL, the toxicity of AA was higher than the OTA cytotoxicity. A slight decrease of IL-8 was observed after 6h, for OTA, while AA slightly increase the IL-8 synthesis. After 24h, IL-8 synthesis was decreased by both toxins, AA having a more pronounced effect than OTA. IL-10 synthesis was not affected by the treatment of both toxins. In conclusion, both OTA and AA negatively affect LLC-PK cells viability and capacity to synthesize IL-8, with AA being more toxic than OTA for the highest concentrations used in this study

Beneficial effect of dietary bioactive compounds from residual nuts, a by-product of pastry on antioxidant defense in pigs after weaning

The walnuts of Juglans regia are rich source of a variety of bioactive compounds like polyunsaturated fatty acids (PUFA omega-6, -9, -3), polyphenols, etc known as antimicrobial and antioxidant substances. In the present study the antioxidant potential of a residual walnuts resulting from the pastry processing was used as a dietary alternative source of antioxidants in pigs after weaning. Thirty crossbred TOPIG hybrid weaned pigs were randomly assigned (n = 10) to three experimental treatments: a normal diet (control group) and two diets included 3 and 5% walnuts residual for 35 days. A high concentration of total polyunsaturated fatty acids, ω-6 (61.0g/100g fat), ω-9 (17.89g/100g fat oleic acid) and ω-3 (11.06g/100g fat) as well as a total phenolic content (PT) of 15.66g GAE/L extract was found in residual walnut. Results indicated an increase of total antioxidant capacity and of the activity of antioxidant enzymes catalaza (CAT) and superoxid dismutaza (SOD) in plasma and liver of pigs fed walnut diets, without effect on glutation peroxidaza (GPx) and biochemical parameters. Further work is necessary to provide data about the effect of other percentage of walnut dietary inclusion and to select the optimum

Dual Effects Exerted in Vitro by Micromolar Concentrations of Deoxynivalenol on Undifferentiated Caco-2 Cells

Contamination of crops used for food and feed production with Fusarium mycotoxins, such as deoxynivalenol (DON), raise important health and economic issues all along the food chain. Acute exposure to high DON concentrations can alter the intestinal barrier, while chronic exposure to lower doses may exert more subtle effects on signal transduction pathways, leading to disturbances in cellular homeostasis. Using real-time cellular impedance measurements, we studied the effects exerted in vitro by low concentrations of DON (0.37–1.50 μM), relevant for mycotoxin-contaminated food, on the proliferation of undifferentiated Caco-2 cells presenting a tumorigenic phenotype. A 1.5 μM concentration of DON maintained cell adherence of non-proliferating Caco-2 cells, whilst arresting the growth of actively proliferating cells compared with control Caco-2 cells in vitro. At 0.37 μM, DON enhanced Caco-2 cell metabolism, thereby triggering a moderate increase in cell proliferation. The results of the current study suggested that low concentrations of DON commonly detected in food may either limit or sustain the proliferation of colon cancer cells, depending on their proliferation status and on DON concentration. Soluble factors released by Lactobacillus strains can partially counteract the inhibitory action of DON on actively proliferating colon cancer cells. The study also emphasized that real-time cellular impedance measurements were a valuable tool for investigating the dynamics of cellular responses to xenobiotics