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The aim of the present study was to evaluate the protective effects of isoflavone (ISO) against zearalenone (ZEA) residues in the muscle and liver tissues of prepubertal gilts. Seventy 75-day-old, prepubertal, female pigs (Duroc × Landrace × Yorkshire, 26.5 ± 0.60 kg) were allocated randomly to seven diet treatments for 21days as follows: one control group (fed the basal diet) and six groups fed the basal diet with the addition of either 0.5 or 2.0 mg/kg ZEA plus either 0, 300 or 600 mg/kg ISO. The results showed that the diet with 2.0 mg/kg ZEA added caused an increase of ZEA residue level in muscle tissue (P < 0.05), and that the addition of both 0.5 and 2.0 mg/kg ZEA increased the residue level of ZEA in the liver of prepubertal gilts (P < 0.05). Addition of 600 mg/kg ISO to 2.0 mg/kg ZEA-contaminated diet decreased the ZEA residue level in liver tissue (P < 0.05), and the addition of 300 or 600 mg/kg ISO to the 2.0 mg/kg ZEA-contaminated diet decreased the residue levels of ZEA in muscle tissue (P < 0.05). Western blot analysis demonstrated that feeding ZEA to prepubertal gilts increased their protein expression of 3α/3β-hydroxysteroid dehydrogenase (HSD; P < 0.05), and that the addition of 300 or 600 mg/kg ISO to the 2.0 mg/kg ZEA-contaminated diet decreased the protein expression of 3α/3β-HSD (P < 0.05), compared with the addition of 2.0 mg/kg ZEA alone. The results demonstrated that muscle and liver tissues retain residual ZEA when pigs are fed a diet contaminated with high concentrations of ZEA, and that the concentration of ZEA in muscle and liver tissues increased with increased amounts of ZEA in the feed. In diets contaminated with high levels of ZEA, the addition of ISO may accelerate the biotransformation and degradation of ZEA and its metabolites, and reduce the residues of ZEA in liver and muscle tissues of prepubertal gilts. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the effect of methionine supplementation above the requirements, as DL-Met (DLM) or OH-Met (HMTBA), during gestation and lactation periods on sows and neonatal piglets' performance. Thirty cross-bred (Landrace x Yorkshire) primiparous sows were fed with a control (CON), DLM or HMTBA diet from 30 days before farrowing to 21 d post-partum. Diets were formulated to meet NRC (2012) recommendations in amino acids except for total sulfur amino acids (TSAA) which were supplied 25% above the level present in the CON, respectively for DLM and HMTBA diets. Dietary Met content in the CON during the gestation period was 0.29% and 0.32% in the lactation period. Dietary Met+Cys content of the CON was 0.52% and 0.60%, respectively for the gestation and lactation periods. Within 12 h of farrowing, all litters were standardized to have 10 piglets per sow. Body weight and backfat thickness (body score) of sows at day 85 and 110 of gestation and 21 d postpartum were measured. Feed intake was also recorded. The reproductive performance of sows, i.e. litter size, total born alive, birth weight and weight gain of progeny was also measured at lactation d7, 14 and 21. Results showed no significant difference of feed intake, body weight and backfat thickness between sows during the gestation and lactation periods. However, when expressed as bodyweight and backfat thickness changes between d21 and d1, significant differences were observed for these two parameters during the lactation period. Sows in the HMTBA treatment showed the lowest changes in body weight as well as backfat thickness in comparison to the CON and DLM groups (P < 0.05). No significant difference was observed on the litters at birth. At postnatal d 14, piglets in the HMTBA (3.81 ± 0.17 kg) and the DLM (3.64 ± 0.20 kg) groups had higher body weights than those in the CON group (3.06 ± 0.19 kg). Similar results were obtained at d 21 with the highest body weight observed with the HMTBA group (+14% in comparison to the CON). Altogether, these results indicated that maternal supplementation of DL-Met and HMTBA, 25% above the recommended level leads to significant improvement of piglets' body weight at weaning age. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the interactive effect of zearalenone (ZEA) and soybean isoflavone (ISO) on the development of reproductive organs, reproductive hormones and estrogen receptor expression in prepubertal gilts. Ninety 75-day-old female pigs (Duroc × Landrace × Yorkshire, 26.50 ± 0.60 kg) were randomly allocated to nine diet treatments during the 21 day study. The experiment employed a 3 × 3 factorial design using a non-soybean meal diet with addition of 0, 0.5 or 2.0mg/kg ZEA and 0, 300 or 600 mg/kg ISO. The results indicated that diets supplemented with 600 mg/kg ISO could reduce the increased weight of the reproductive organs induced by ZEA at 2mg/kg (P<0.05) while feed containing ISO and 0.5mg/kg ZEA increased the weight of the reproductive organs compared with pigs fed diets with 0.5mg/kg ZEA alone. Diets with ISO at 600 mg/kg reduced the large width of vulvas induced by diets with 2mg/kg ZEA (P<0.05). Simultaneous provision of ZEA and ISO to prepubertal gilts increased the level of E2 at days 7 and 14, but decreased it at day 21 (P<0.05). Pigs simultaneously fed 2mg/kg ZEA and 600 mg/kg ISO had the highest level of FSH (P<0.05). There was a significant interaction (P<0.05) between ZEA and ISO supplementation on the level of LH, and pigs offered diets with 2mg/kg ZEA and 600 mg/kg ISO had the lowest level of LH on days 14 and 21. Animals supplemented simultaneously with ZEA and ISO showed higher ERα/ERβ mRNA expression compared to those offered diets containing 0.5mg/kg ZEA alone or basal diets. However, this simultaneous supplementation resulted in a lower level of ERα/ERβ mRNA expression compared to offering diets with 2mg/kg ZEA alone. It appears that ISO can counteract the estrogenic influence of a high dosage of ZEA (2mg/kg). This affect might be attributed to competitive binding with estrogen receptors, thereby weakening the estrogenic effect of ZEA. Meanwhile, interactions between ZEA and ISO may interfere with the functioning of E2, FSH and LH in prepubertal gilts., (Copyright © 2010 Elsevier B.V. All rights reserved.)

The relationship between intracellular free calcium ion concentrations ([Ca2+]i) and release of arachidonic acid from membrane phospholipids following peroxidation was examined in rabbit aortic endothelial cells treated with linoleic acid hydroperoxide (LOOH). LOOH (0.1-0.4) mumol/10(6) cells) caused a rapid and dose-dependent transient increase in [Ca2+]i in the presence of extracellular Ca2+ that remained elevated over baseline for 15 to 30 s. In the absence of extracellular Ca2+, LOOH also evoked a transient increase in [Ca2+]i of lesser magnitude which immediately returned to basal (or below basal) levels. In this regard, the rise in intracellular Ca2+ after LOOH or vasopressin (AVP) treatments involved, at least in part, related intracellular pools that in each case was followed by influx of extracellular Ca2+. The intracellular membrane sources known to be affected by vasopressin were not directly involved. Most notably, the LOOH evoked rise in [Ca2+]i was not associated with release of IP3, suggesting that the source of intracellular Ca2+ is not IP3-sensitive pools. However, pretreatment with LOOH strongly inhibited the rise in [Ca2+]i upon subsequent addition of AVP or LOOH and the extent of such inhibition was dependent on the availability of free intracellular Ca2+ and presence of extracellular Ca2+. These findings suggest that reuptake of Ca2+ into intracellular membrane pools is reduced in the presence of LOOH and/or the availability of Ca2+ from agonist-sensitive sites is inhibited by LOOH. An increase in free 20:4 levels was found after LOOH treatment that was only partly prevented using intracellular Ca2+ chelators which maintained [Ca2+]i at basal levels after LOOH treatment. These findings suggest that LOOH induction of phospholipid hydrolysis proceeds following small transients in [Ca2+]i that are considerably less than that evoked by agents such as AVP, approximating basal Ca2+ concentrations. Inhibition of LOOH-induced lipid peroxidation by vitamin E also prevented the rise in [Ca2+]i and 20:4 release indicating that phospholipid hydrolysis is dependent, at least in part, on membrane lipid peroxidation. Inhibition of protein kinase C (PKC) completely blocked LOOH-induced release of 20:4 but had little effect on the LOOH-induced rise in [Ca2+]i, suggesting an indirect relationship between LOOH-induced membrane Ca2+ signalling events, with intervention via PKC-mediated induction of phospholipid hydrolysis. A rapid and progressive translocation of PKC to the membrane fraction was evident after LOOH addition over the time course corresponding to the maximal release of 20:4 which was also inhibited by vitamin E.(ABSTRACT TRUNCATED AT 400 WORDS)

Infrared vibration spectroscopy appears to be a more powerful technique for tumor diagnosis than visible or UV spectroscopy. In the present work, Fourier-transform infrared (FTIR) spectroscopy was used to compare cultured normal fibroblast and fibrosarcoma cells. Significant differences were observed by comparing the spectra of the normal human cells with that of the cancer cells. The PO2 symmetric stretching mode at 1082 cm-1 is shifted to a higher frequency in the cancer cell and a broad band, whose center is located at 1064 cm-1 in the cancer cell is reduced in intensity. In addition, the decrease in intensity of the CH2 bending mode relative to that of CH3 mode is detectable only in the fibrosarcoma cell. This FTIR difference between fibroblast and fibrosarcoma cells suggests that either fatty acid chains or protein side chains of the cancer cells are partially degraded resulting in more terminal carbon (e.g., CH3). It is also possible that changes in the environment upon carcinogenesis induces a change in the relative absorption cross section for CH3 and CH2 bending vibrations. These results suggest that FTIR spectroscopy may become a promising and sensitive technique for tumor identification.

Bacteriorhodopsin (bR) is found previously to have two high-affinity and four to six low-affinity Ca2+ binding sites. Our previous studies with site-directed mutation suggested that the two high-affinity sites are located within the protein and close to the retinal pocket. In order to investigate the location of the four to six low-affinity binding sites, we studied Ca2+ binding to deionized bR as well as its variant in which its C-terminus is removed by papain treatment. Potentiometric titration with Ca(2+)-selective electrodes were carried out and Scatchard plots were obtained from the titration data. We found that most of the low-affinity sites are eliminated upon removal of the C-terminus in bR. This suggests that the low-affinity sites in bR are on the surface. The involvement of the C-terminus in these sites is discussed.

The renal tissue of 12-, 29-, 90- and 165-day-old genetically obese, hyperphagic, diabetic KKAy and age-matched nondiabetic C57BL/6 mice was morphometrically analyzed to characterize the development of peripheral glomerular capillary basement membrane thickening in the kidney of this animal model. Peripheral glomerular basement membrane (GBM) thickness was unremarkable in KKAy mice at 12 days of age (prior to onset of hyperinsulinemia) or at 29 days of age (after development of hyperinsulinemia). By 90 days of age, when the KKAy mice became severely hyperinsulinemic and hyperglycemic, the peripheral GBM thickness was greater (13%, p less than 0.002) in the diabetic compared with the nondiabetic mice. Furthermore, the peripheral GBM thickness was exacerbated (20%, p less than 0.001) by 165 days of age in the KKAy mice. The results of the present study suggest that peripheral glomerular capillary basement membrane thickening has an early onset and develops rapidly in the KKAy mouse in comparison with other diabetic animal models. Therefore, the KKAy mouse seems to be an appropriate model for further investigation of early structural and functional defects in the glomerular filtration barrier.