DL-Selenomethionine Alleviates Oxidative Stress Induced by Zearalenone via Nrf2/Keap1 Signaling Pathway in IPEC-J2 Cells

Zearalenone (ZEN) is a kind of nonsteroidal mycotoxin that is considered a risk affecting the safety of human food and livestock feed that causes oxidative damages in mammalian cells. Selenomethionine (SeMet) was indicated to have antioxidant activity and received great interest in investigating the role of SeMet as a therapeutic agent in oxidation. Therefore, the aim of this study was to investigate the hormetic role of DL-SeMet in porcine intestinal epithelial J2 (IPEC-J2) cells against ZEN-induced oxidative stress injury. As a result of this experiment, 30 μg/mL of ZEN was observed with significantly statistical effects in cell viability. Following the dose-dependent manner, 20 μg/mL was chosen for the subsequent experiments. Then, further results in the current study showed that the ZENinduced oxidative stress with subsequent suppression of the expression of antioxidant stress pathway-related genes species. Moreover, SeMet reversed the oxidative damage and cell death of ZEN toxins to some extent, by a Nrf2/Keap1-ARE pathway. The finding of this experiment provided a foundation for further research on the ZEN-caused cell oxidative damage and the cure technology

Optimisation of the Enzymatic Hydrolysis of Blood Cells with a Neutral Protease

For utilizing the blood cells (BCs) effectively, enzymatic hydrolysis was applied to produce the enzymatically hydrolyzed blood cells (EHBCs) by using a neutral protease as a catalyst. The results of the single-factor experiments showed optimal substrate concentration, enzyme to substrate ratio (E/S), pH, temperature, and incubation period were 1.00%, 0.10, 7.00, 50.00°C, and 12.00 h, respectively. The optimized hydrolysis conditions from response surface methodology (RSM) were pH 6.50, E/S 0.11, temperature 45.00°C, and incubation period 12.00 h. Under these conditions (substrate concentration 1.00%), the degree of hydrolysis (DH) was 35.06%. The free amino acids (FAAs) content of the EHBCs (35.24%) was 40.46 times higher than BCs while the total amino acids (TAAs) content was lower than BCs. The scores of lysine (human 0.87; pig 0.97), valine (human 1.42; pig 1.38), leucine (human 1.50; pig 1.90), tyrosine (human 0.84; pig 1.09), and histidine (human 2.17; pig 2.50) indicated that the EHBCs basically fulfilled the adult human and pig nutritional requirements. The calculated protein efficiency ratios (C-PERs) of the EHBCs were 3.94, 6.19, 21.73, and 2.04. In summary, the EHBCs were produced successfully with optimized conditions and could be a novel protein source for humans and pigs

Effects of modified maifanite on zearalenone toxicity in female weaner pigs

The experiment was conducted to investigate alleviative effects of modified maifanite (MMF) on zearalenone (ZEN) toxicity in female weaner pigs. In this experiment, 32 female weaner pigs (Duroc×Landrace×Large white, 10.50±0.07 kg) were divided into 4 groups (8 pigs/group): control group (0.02 mg/kg ZEN); ZEN-treated group (1.11 mg/kg ZEN); MMF-treated group (1% MMF); ZEN+MMF treated group (1.11 mg/kg ZEN and 1% MMF), The trial period lasted for 28 d. Growth performance, vulva size, genital organs, antioxidant enzyme activities, serum metabolites and ZEN residues in female weaner pigs were determined. The results showed that the treatments had no effect on growth performance and length and width of the vulva. However, vulva area (P=0.038) and progesterone (P=0.022) were affected by the ZEN×MMF interaction. Treatment with ZEN resulted in a significant increase of the genital organ weight (P=0.002) and decrease of serum superoxide dismutase (P=0.017) activity. Feeding of the ZEN diet decreased the number of red blood cells (P=0.009) and platelets (P=0.002). The MMF reduced methane dicarboxylic aldehyde concentration when fed with ZEN diet but not when fed with the basal diet (ZEN×MMF, P=0.018). In the liver, feeding of the ZEN diet with MMF reduced the levels of ZEN residues (P=0.003). Our findings suggest that the addition of MMF to ZEN diet resulted in partial restoration of antioxidant status and reduced ZEN levels in the liver

Thymol Alleviates LPS-Induced Liver Inflammation and Apoptosis by Inhibiting NLRP3 Inflammasome Activation and the AMPK-mTOR-Autophagy Pathway

Thymol is a natural antibacterial agent found in the essential oil extracted from thyme, which has been proven to be beneficial in food and medicine. Meanwhile, the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome and autophagy have been reported to play key roles in the progression of liver injury. However, the effects of thymol on the NLRP3 inflammasome and autophagy in protecting the liver remain unclear. The present study used a mouse model with liver injury induced by lipopolysaccharides (LPS) to investigate the regulatory mechanisms of thymol. We found that thymol alleviated LPS-induced liver structural damage, as judged by reduced inflammatory cell infiltration and improved structure. In addition, elevated levels of the liver damage indicators (alanine transaminase (ALT), aspartate transaminase (AST), and total bilirubin (TBIL)) dropped after thymol administration. The mRNA and protein expression of inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-22), apoptosis-related genes (caspase3 and caspase9), and the activity of apoptosis-related genes (caspase3 and caspase9) were increased in LPS-treated livers, whereas the changes were alleviated after thymol administration. Thymol inhibited LPS-induced increment in lactate dehydrogenase (LDH) activity in primary hepatocytes of the mouse. In addition, thymol protected mice from liver injury by inhibiting NLRP3 inflammasome activation induced by LPS. Mechanistically, the present study indicates that thymol has liver protective activity resulting from the modulation of the AMP-activated protein kinase—mammalian target of rapamycin (AMPK–mTOR) to regulate the autophagy pathway, hence curbing inflammation

Design of embedded-hybrid antimicrobial peptides with enhanced cell selectivity and anti-biofilm activity.

Antimicrobial peptides have attracted considerable attention because of their broad-spectrum antimicrobial activity and their low prognostic to induce antibiotic resistance which is the most common source of failure in bacterial infection treatment along with biofilms. The method to design hybrid peptide integrating different functional domains of peptides has many advantages. In this study, we designed an embedded-hybrid peptide R-FV-I16 by replacing a functional defective sequence RR7 with the anti-biofilm sequence FV7 embedded in the middle position of peptide RI16. The results demonstrated that the synthetic hybrid the peptide R-FV-I16 had potent antimicrobial activity over a wide range of Gram-negative and Gram-positive bacteria, as well as anti-biofilm activity. More importantly, R-FV-I16 showed lower hemolytic activity and cytotoxicity. Fluorescent assays demonstrated that R-FV-I16 depolarized the outer and the inner bacterial membranes, while scanning electron microscopy and transmission electron microscopy further indicated that this peptide killed bacterial cells by disrupting the cell membrane, thereby damaging membrane integrity. Results from SEM also provided evidence that R-FV-I16 inherited anti-biofilm activity from the functional peptide sequence FV7. Embedded-hybrid peptides could provide a new pattern for combining different functional domains and showing an effective avenue to screen for novel antimicrobial agents

Importance of Tryptophan in Transforming an Amphipathic Peptide into a Pseudomonas aeruginosa-Targeted Antimicrobial Peptide.

Here, we found that simple substitution of amino acids in the middle position of the hydrophobic face of an amphipathic peptide RI16 with tryptophan (T9W) considerably transformed into an antimicrobial peptide specifically targeting Pseudomonas aeruginosa. Minimal inhibitory concentration (MIC) results demonstrated that T9W had a strong and specifically antimicrobial activity against P. aeruginosa, including antibiotic-resistant strains, but was not active against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Staphyfococcus epidermidis. Fluorescent spectroscopic assays indicated that T9W interacted with the membrane of P. aeruginosa, depolarizing the outer and the inner membrane of bacterial cells. Salt susceptibility assay showed that T9W still maintained its strong anti-pseudomonas activity in the presence of salts at physiological concentrations, and in hemolytic and MTT assays T9W also showed no toxicity against human blood cells and macrophages. In vivo assay demonstrated that T9W also displayed no toxicity to Chinese Kun Ming (KM) mice. Furthermore, the strong antibiofilm activity was also observed with the peptide T9W, which decreased the percentage of biomass formation in a dose-dependent manner. Overall, these findings indicated that design of single-pathogen antimicrobial agents can be achieved by simple amino acid mutation in naturally occurring peptide sequences and this study suggested a model of optimization/design of anti-pseudomonas drugs in which the tryptophan residue was a conserved element

Effects of the antimicrobial peptide WK3 on diarrhea, growth performance and intestinal health of weaned piglets challenged with enterotoxigenic Escherichia coli K88

Background: Antibiotics are very effective for treating diarrhea in weaned pigs, but the global prohibition of antibiotics makes it urgent to find an alternative to antibiotics. Objective: An experiment was conducted to determine the antimicrobial activity of a linear trpzip-like β-hairpin antimicrobial peptide WK3 in vivo and to assess its effects on growth performance and intestinal health. Design: Thirty-two piglets were weaned at 21 days and housed in individual metabolic cages, which were randomly divided into four groups and were maintained on a corn-soybean meal-based basal diet. Group 1 included a blank group. Groups 2, 3, and 4 were orally infected by feeding with Enterotoxigenic Escherichia coli (ETEC) K88, which was followed by saline treatment (group 2), enrofloxacin injection at a dose of 2.5 mg/kg (group 3), and WK3 injection at a dose of 2 mg/kg (group 4). The experiment lasted for 6 days, and feed and water were provided ad libitum. Results: Both WK3 and enrofloxacin effectively attenuated diarrhea and improved growth performance of piglets. Compared with the control group, WK3 significantly improved the villus height in the ileum (P 0.05). WK3 also reduced the numbers of Enterococcus spp (P < 0.01) in the cecal contents, and the number of Enterobacterium spp tended to decrease (0.05 < P < 0.1). Moreover, the jejunal mucosa of the WK3 group exhibited lower interleukin-1α (IL-1a; P < 0.01), toll-like receptors-4 (TLR-4; P < 0.05), and myeloid differentiation primary response 88 (MyD88; P < 0.01) messenger ribonucleic acid (mRNA) expression levels. The jejunum of the WK3 group also exhibited an increased antioxidant capacity, reduced concentration of malondialdehyde (MDA; P < 0.05), and enhanced superoxide dismutase (SOD) activity (P < 0.05). Conclusions: WK3 has the potential to replace antibiotics as a new generation feed additive

Dietary intake of broiler breeder hens during the laying period affects amino acid and fatty acid profiles in eggs

The objective of this study was to evaluate the effects of maternal dietary intake on the amino acid and fatty acid contents in eggs during the laying period. An experiment with a 2×2 factorial design was conducted with two maternal dietary intake levels (100 and 75% of dietary intake recommended by the Chinese Ministry of Agriculture) and two broiler lines (fat and lean line). A total of 384 hens of fat line and 384 hens of lean line at 23 weeks of age were included in the experiment. Each line was randomly divided into two treatments (n = 192 in each treatment, with 12 replications), and each replication included 16 birds. The treatments were LN (lean line and normal maternal dietary intake, n = 192), LL (lean line and low maternal dietary intake, n = 192), FN (fat line and normal maternal dietary intake, n = 192), and FL (fat line and low maternal dietary intake, n = 192). The amino acid and fatty acid contents in eggs were tested (50 weeks of age). The fat line had higher levels of arginine, aspartic acid, glycine, histidine, leucine, methionine, and threonine in the egg albumen than the lean line. Low maternal dietary intake increased the cystine deposition in egg yolks. There were interactions between maternal dietary intake and line on the deposition of trans-oleic acid, docosanoic acid, and total fatty acid in egg yolks. Low maternal dietary intake increased the deposition of tetradecenoic and linolenic acids and the ratio of total polyunsaturated fatty acids to total saturated fatty acid in egg yolks but decreased the deposition of docosanoic acid. Maternal dietary intake and line affect the amino acid and fatty acid profiles in egg