Effect of 2alpha-hydroxyursolic acid on NF-kappaB activation induced by TNF-alpha in human breast cancer MCF-7 cells

Apples are one of the largest contributors of fruit phenolics of all fruits consumed by Americans and contain a variety of bioactive compounds, which have health benefits. Consumption of apples has been linked to reduced risk of chronic diseases such as cancer and cardiovascular disease. Apple extracts have been shown to have the capabilities of inhibiting NF-kappaB activation in human breast cancer MCF-7 cells. 2Alpha-hydroxyursolic acid is one of the major triterpenoids isolated from apple peels, and its effects on cell proliferation and TNF-alpha-induced NF-kappaB activation in MCF-7 cells were examined. 2Alpha-hydroxyursolic acid significantly inhibited MCF-7 cell proliferation at doses of 20 microM (p < 0.05). Preincubation with 2alpha-hydroxyursolic acid suppressed TNF-alpha-induced NF-kappaB activation in a dose-dependent manner and significantly inhibited the activation at a dose of 20 microM of 2alpha-hydroxyursolic acid (p < 0.05). 2Alpha-hydroxyursolic acid treatment did not affect the phosphorylation level of NF-kappaB inhibitor (IkappaB-alpha), but proteasome activity in MCF-7 cells was inhibited significantly at doses of 10 and 20 microM ( p < 0.05). These results suggest that 2alpha-hydroxyursolic acid has antiproliferative activities against MCF-7 cells and capabilities inhibiting NF-kappaB activation induced by TNF-alpha partially by suppressing proteasome activities.     

Panax ginseng extract rich in ginsenoside protopanaxatriol attenuates blood pressure elevation in spontaneously hypertensive rats by affecting the Akt-dependent phosphorylation of endothelial nitric oxide synthase

Nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) is a fundamental regulator of systemic blood pressure. Ginsenosides from Panax ginseng have been investigated in vitro for the molecular and biochemical mechanisms by which they stimulate NO release in vascular endothelial cells; however, little research has been done to confirm the physiological relevance of these in vitro studies. To address this research gap, the effects of a P. ginseng extract rich in ginsenosides from protopanaxatriol on spontaneously hypertensive rats (SHRs) was examined. Ginseng extract administration stimulated nongenomic Akt-mediated eNOS activation, enhanced NO production, improved vessel wall thickening, and alleviated hypertension in SHRs, confirming the physiological relevance of previous in vitro studies with ginsenosides.     

Fortification of Wheat Dough with Calcium and Magnesium Ions Affects Empirical Rheological Properties

This study evaluated the influence of calcium and magnesium ions on the empirical rheological properties of wheat flour to verify possible effects of these ions on processing because, in addition to their nutritional importance, they are also responsible for water hardness. Calcium (0–1.30 g/100 g) and magnesium (0–0.34 g/100 g) ions from sulfate salts were added to wheat flour, according to a central composite rotatable design. The farinograph and extensigraph properties of wheat flour and its mixtures were evaluated. The results were analyzed by response surface methodology. Calcium ions stood out for increasing water absorption, decreasing mixing stability, and producing a delayed effect on dough extensibility (reduced at 135 min). Magnesium ions influenced most flour rheological properties in a similar manner to oxidizing agents (increased dough stability, increased resistance to extension, and reduced extensibility), thus proving to be a possible replacement agent for these additives. An interaction effect of the combined calcium and magnesium ions was observed on dough development time. The results showed that effects on processing can occur when wheat flour fortification is made, and adaptations on wheat flour specifications, product formulation, and processing parameters may be required.     

Bowman-Birk and Kunitz Protease Inhibitors among Antinutrients and Bioactives Modified by Germination and Hydrolysis in Brazilian Soybean Cultivar BRS 133

Soybean contains constituents that have antinutritional and bioactive properties. Enzymatic hydrolysis and germination can enhance the biological activity of these compounds in soybean. The objective of this study was to investigate the effect of germination, Alcalase (protease) hydrolysis, and their combination on the concentrations of antinutritional and bioactive compounds in Brazilian soybean cultivar BRS 133. A combination of germination and Alcalase hydrolysis resulted in the degradation of Bowman-Birk inhibitor (BBI), Kunitz trypsin inhibitor (KTI), and lunasin by 96.9, 97.8, and 38.4%. Lectin was not affected by any of the processing treatments when compared to nongerminated and nonhydrolyzed soy protein extract. Total isoflavones (ISF) and total saponins (SAP) increased by 16.2 and 28.7%, respectively, after 18 h of germination, while Alcalase hydrolysis led to the reduction of these compounds. A significant correlation was found between concentrations of BBI and KTI, BBI and lunasin, BBI and ISF, KTI and lunasin, KTI and ISF, KTI and SAP, lunasin and ISF, and ISF and SAP. Germination and Alcalase hydrolysis interacted in reducing BBI, ISF, and SAP. This study presents a process of preparing soy flour ingredients with lower concentrations of antinutritional factors and with biologically active constituents, important for the promotion of health associated with soybean consumption. In conclusion, 18 h of germination and 3 h of Alcalase hydrolysis is recommended for elimination of protease inhibitors, while bioactives are maintained by at least 50% of their original concentrations.     

Differences in polymer formation through disulfide bonding of recombinant light meromyosin between white croaker and walleye pollack and their possible relation to species specific differences in thermal unfolding

Fast skeletal light meromyosins (LMMs) of white croaker and walleye pollack were prepared in our expression system using Escherichia coli and determined for their polymer-forming ability and thermodynamic properties by using sodium dodecyl sulfate polyacrylamide gel electrophoresis and differential scanning calorimetry (DSC), respectively. White croaker LMM formed dimer by heating at 80 degrees C and showed only a single peak at 32.1 degrees C of temperature transition in DSC. On the other hand, walleye pollack LMM hardly formed polymer and showed four peaks at 27.7, 30.5, 35.8, and 43.9 degrees C. When Cys525 of white croaker LMM was replaced by alanine, this point-mutated LMM showed no change in its DSC profile but formed no dimer upon heating, suggesting a possible role of Cys525 in dimer formation. On the other hand, walleye pollack LMM where Cys491 was substituted by alanine changed its DSC profile, showing four peaks at 27.9, 29.1, 38.4, and 43.9 degrees C. However, this point-mutated LMM formed no dimer upon heating as in the case of native LMM. These results suggest that cysteine residue(s) participates in thermal gel formation of LMM when it locates in a suitable position of the sequence.     

Synthesis of conjugated linoleic acid by human-derived Bifidobacterium breve LMC 017: utilization as a functional starter culture for milk fermentation

This study was performed to discover bifidobacteria isolated from human intestines that optimally convert linoleic acid (LA) to conjugated linoleic acid (CLA) and to optimize the culture conditions of milk fermentation. One hundred and fifty neonatal bifidobacteria were screened for CLA-producing ability, and Bifidobacterium breve LMC 017 was selected as it showed about 90% conversion of free LA in MRS broth. The selected strain showed resistance at 0.5% LA in microaerophillic conditions. When monolinolein (LA 90%) was used as a substrate for CLA production, the conversion rate was lower compared to free LA, but the growth rate was unaffected during the milk fermentation. There was no significant difference in CLA production between aerobic and anaerobic conditions, and little decline in CLA was shown after the maximal CLA level had been reached. CLA production increased by 80% with 24 h of incubation in milk containing additional skim milk (5%), where the proteins may have facilitated the production of CLA by enhancing the interaction of substrate with the bacteria. CLA production did not decline after 9 h of fermentation and an additional 12 weeks of storage with other commercial starters. This demonstrates the possibility of using this strain as a costarter in the production of CLA-enriched yogurt.     

Epigallocatechin-3-gallate suppresses hemin-aggravated colon carcinogenesis through Nrf2-inhibited mitochondrial reactive oxygen species accumulation

BackgroundPrevious studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood.ObjectivesWe aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action.MethodsHemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model.ResultsIn Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model.ConclusionsWe demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.     

Preferential expression of L-type amino acid transporter 1 in ameloblasts during rat tooth development

Certain amino acid transport systems play an important role in supplying organic nutrients to each cell and for cell proliferation during tooth development. However, the mechanisms responsible for such actions are unclear. This study demonstrated for the first time that LAT1 and 4F2hc are expressed during tooth development in prenatal and postnatal rats, and that the transporters show cell-specific expression in ameloblasts, which are the epithelium-derived dental cells. LAT1 and 4F2hc expression was not observed in other dental cells of the developing teeth such as odontoblasts and cementoblasts. Overall, these results suggest that LAT1 and 4F2hc might play an important role in enamel formation.     

Monoclonal antibody analysis of porcine reproductive and respiratory syndrome virus epitopes associated with antibody-dependent enhancement and neutralization of virus infection

Enhanced infection and replication of porcine reproductive and respiratory syndrome (PRRS) virus in the presence of specific antibody has been demonstrated in vitro and in vivo, a phenomenon known as antibody-dependent enhancement (ADE). ADE is considered to be a significant obstacle to developing effective vaccines for many viruses for which ADE has been reported, since virus-specific antibodies of maternal origin or those conferred by vaccination can facilitate the entry of the virus into target cells, sometimes resulting in increased severity of the disease. In this study, the role of specific PRRS viral epitopes in ADE and/or virus neutralization (VN) was assessed in vitro using 14 monoclonal antibodies (mAbs) to 4 PRRS viral proteins: nucleocapsid (N), matrix (M), glycoprotein (GP) 5, and GP3. Each mAb recognized a distinct epitope on one of these proteins. One-way ADE and VN assays were performed in vitro using homologous PRRS virus isolates in the presence or absence of each mAb. ADE activity was determined by detecting a significant increase of progeny virus yield in porcine alveolar macrophage cultures in the presence of individual mAbs. Neutralizing activity was determined by detecting a significant reduction or complete blocking of virus replication in MARC-145 cells in the presence of individual mAbs. mAbs could be categorized into 3 groups: enhancing, neutralizing and neither. Viral epitopes which are capable of inducing neutralizing antibodies appeared to reside on the M, GP3 and GP5 proteins, while epitopes that may induce ADE-mediating antibody were associated with the N and GP5 proteins. Identification of the viral proteins and antigens and epitopes responsible for ADE- and VN-mediating antibodies may provide the basis for developing efficacious second-generation vaccines for the control of PRRS virus; yet, further epitope mapping remains to be done.