Search Results (6)

Polycyclic aromatic hydrocarbons (PAHs), prevalent aquatic contaminants, arise from burning fossil fuels, a major source of greenhouse gases driving global warming. PAHs and warmer temperatures individually exert diverse negative effects on aquatic organisms. However, the effects of PAH exposure and/or rising temperature remain largely unknown. Liver in vitro models, like the rainbow trout (Oncorhynchus mykiss) RTL-W1 liver cell line, have been employed to unravel PAH-exposure effects, primarily on cell viability and enzymatic activity. Here, monolayer-cultured (2D) RTL-W1 cells were used to assess the co-exposure effects of temperature (18 and 21 °C) and two PAHs, benzo[a]pyrene (B[a]P) and benzo[k]fluoranthene (B[k]F), at 10 and 100 nM. After a 72 h exposure, the cell density and viability were evaluated using the trypan blue and LDH assays. The mRNA levels of the detoxification-associated genes aryl hydrocarbon receptor (AhR), cytochrome P450 (CYP)1A, CYP3A27, glutathione S-transferase omega 1 (GSTO1), uridine diphosphate–glucuronosyltransferase (UGT), catalase (CAT), and multidrug resistance-associated protein 2 (MRP2) were measured by RT-qPCR. Temperature influenced cell viability and LDH leakage. Both PAHs reduced the cell density and upregulated the mRNA levels of AhR, CYP1A, CYP3A27, and UGT, while GSTO1 and MRP2 were only augmented after the higher B[k]F concentration. Temperature influenced CAT and UGT expression. There was no interaction between temperature and the PAHs. Overall, the results show that B[k]F has more effects on detoxification targets than B[a]P, whereas a temperature increase mildly affects gene expression. The RTL-W1 in 2D seems useful for unravelling not only the liver effects of PAH but also the impact of temperature stress. Full article

The present pilot study aimed to investigate whether common single nucleotide polymorphisms (SNPs) in the gene encoding glutathione S-transferase omega 1 (GSTO1), both individually and in combination with variants of the catalytic subunit of the glutamate cysteine ligase (GCLC) gene and environmental risk factors, are associated with the risk of psoriasis. The research included a total of 944 participants, comprising 474 individuals diagnosed with psoriasis and 470 healthy control subjects. Five common SNPs in the GSTO1 gene—specifically, rs11191736, rs34040810, rs2289964, rs11191979, and rs187304410—were genotyped in the study groups using the MassARRAY-4 system. The allele rs187304410-A (OR = 0.19, 95% CI 0.04–0.86, Pperm = 0.02) and the genotype rs187304410-G/A (OR = 0.19, 95% CI 0.04–0.85, Pperm = 0.01) were found to be associated with psoriasis in females. The model-based multifactor dimensionality reduction approach facilitated the identification of higher-order epistatic interactions between the variants of the GSTO1 and GCLC genes (Pperm < 0.0001). These interactions, along with the risk factor of alcohol abuse, collectively contribute to the pathogenesis of psoriasis. This study is the first to demonstrate that polymorphisms in the GSTO1 gene, both individually and in combination with variants of the GCLC gene and alcohol abuse, are associated with an increased risk of psoriasis. Full article

Glutathione S-transferase omega 1 (GstO1) catalyzes deglutathionylation and plays an important role in the protein glutathionylation cycle in cells. GstO1 contains four conserved cysteine residues (C32, C90, C191, C236) found to be mutated in patients with associated diseases. In this study, we investigated the effects of cysteine mutations on the structure and function of GstO1 under different redox conditions. Wild-type GstO1 (WT) was highly sensitive to hydrogen peroxide (H₂O₂), which caused precipitation and denaturation at a physiological temperature. However, glutathione efficiently inhibited the H₂O₂-induced denaturation of GstO1. Cysteine mutants C32A and C236A exhibited redox-dependent stabilities and enzyme activities significantly different from those of WT. These results indicate that C32 and C236 play critical roles in GstO1 regulation by sensing redox environments and explain the pathological effect of cysteine mutations found in patients with associated diseases. Full article

The aim of this study was to investigate the effects of dietary l-glutamine (Gln) supplementation on the morphology and function of the intestine and the growth of muscle in piglets. In this study, sixteen 21-day-old piglets were randomly divided into two groups: the Control group (fed a basal diet) and the Gln group (fed a basal diet supplemented with 0.81% Gln). Blood, gut, and muscle samples were collected from all piglets on Day 20 of the trial. Compared with the Control group, the supplementation of Gln increased (p < 0.05) the villus height, villus width, villus surface area, and villus height/crypt depth ratio of the small intestine. Furthermore, the supplementation of Gln increased (p < 0.05) total protein, total protein/DNA, and RNA/DNA in both the jejunum and ileum. It also increased (p < 0.05) the concentrations of carnosine and citrulline in the jejunal mucosa, as well as citrulline and cysteine concentrations in the ileum. Conversely, Gln supplementation decreased (p < 0.05) Gln concentrations in both the jejunum and ileum, along with β-aminoisobutyric acid and 1-Methylhistidine concentrations, specifically in the ileum. Subsequent research revealed that Gln supplementation increased (p < 0.05) the mRNA levels for glutathione-S-transferase omega 2 and interferon-β in the duodenum. In addition, Gln supplementation led to an increase (p < 0.05) in the number of Lactobacillus genus in the colon, but a decrease (p < 0.05) in the level of HSP70 in the jejunum and the activity of diamine oxidase in plasma. Also, Gln supplementation reduced (p < 0.05) the mRNA levels of glutathione-S-transferase omega 2 and interferon stimulated genes, such as MX1, OAS1, IFIT1, IFIT2, IFIT3, and IFIT5 in both the jejunum and ileum, and the numbers of Clostridium coccoides, Enterococcus genus, and Enterobacterium family in the colon. Moreover, Gln supplementation enhanced (p < 0.05) the concentrations of total protein, RNA/DNA, and total protein/DNA ratio in the longissimus dorsi muscle, the concentrations of citrulline, ornithine, arginine, and hydroxyproline, and the mRNA level of peptide transporter 1, while reducing the contents of hydrogen peroxide and malondialdehyde and the mRNA level of glutathione-S-transferase omega 2 in the longissimus dorsi muscle. In conclusion, dietary Gln supplementation can improve the intestinal function of piglets and promote the growth of the longissimus dorsi muscle. Full article

Mono-lactate glyceride (LG) is a short-chain fatty acid ester. It has been shown that short-chain fatty acid esters play an important role in maintaining intestinal structure and function. The aim of this study is to investigate the effects of mono-lactate glyceride on growth performance and intestinal morphology and function in weaned piglets. Sixteen 21-day-old weaned piglets of similar weight were distributed arbitrarily to two treatments: The control group (basal diet) and the LG group (basal diet + 0.6% mono-lactate glyceride). The experiment lasted for 21 days. On day 21 of the trial, piglets were weighed, and blood and intestinal samples were collected for further analysis. Results showed that dietary supplementation with 0.6% mono-lactate glyceride decreased (p < 0.05) the diarrhea rate and the contents of malondialdehyde and hydrogen peroxide in the ileum and jejunum and increased (p < 0.05) the expression of intestinal tight junction protein (Occludin) and the activities of superoxide dismutase and catalase in the ileum and colon. In addition, mono-lactate glyceride supplementation could enhance intestinal mucosal growth by increasing (p < 0.05) the mRNA levels of extracellular regulated protein kinases, promote intestinal mucosal water and nutrient transport and lipid metabolism by increasing (p < 0.05) the mRNA levels of b^0,+ amino acid transporter, aquaporin 3, aquaporin 10, gap junction protein alpha 1, intestinal fatty acid-binding protein, and lipoprotein lipase, enhance antiviral and immune function by increasing (p < 0.05) the mRNA levels of nuclear factor kappa-B, interferon-β, mucovirus resistance protein II, 2’-5’-oligoadenylate synthetase-like, interferon-γ, C-C motif chemokine ligand 2, and toll-like receptor 4, and enhance antioxidant capacity by increasing (p < 0.05) the mRNA levels of NF-E2-related factor 2 and glutathione S-transferase omega 2 and decreasing (p < 0.05) the mRNA level of NADPH oxidase 2. These results suggested that dietary supplementation with mono-lactate glyceride could decrease the diarrhea rate by improving intestinal antioxidant capacity, intestinal mucosal barrier, intestinal immune defense function, and intestinal mucosal water and nutrient transport. Collectively, dietary supplementation with 0.6% mono-lactate glyceride improved the intestinal function of weaned piglets. Full article

This study examined the effects of various types, quality, and levels of dietary oils on laying performance and the expression patterns of antioxidant-related genes in Hy-line brown laying hens. A total of 720 40-week-old Hy-line brown laying hens were fed the same corn-soybean basal meals but containing 0.5 or 1.5% normal or oxidized soybean oil or lard, a total of 8 treatments. The results showed that laying rate (LR) and fatty acids of raw yolk were significantly correlated dietary type of oil (p < 0.05). With the increasing concentration of normal oil, it significantly increased LR and decreased feed conversion ratio (FCR, feed/egg) and albumen height of laying hens. The oxidized oil significant decreased the production performance of laying hens; and adding 1.5% of oxidized lard into feeds could destroy the integrity of yolk spheres of cooked yolk. mRNA expression of liver antioxidant-related genes increased when dietary oxidized oils were added into feeds. By comparing different qualities oil effect on antioxidant-related genes, the expression of Glutathione S-Transferase Theta 1 (GSTT1), Glutathione S-Transferase Alpha 3 (GSTA3), Glutathione S-Transferase Omega 2 (GSTO2), and Superoxide Dismutase 2 (SOD2) were increased when dietary oils were oxidized, in which change of the GSTO2 expression was the most with 1.5% of oxidized soybean oil. In conclusion, the ideal type of oil for Hy-line brown layer hens is soybean comparing with lard in a corn-soybean diet, avoiding using of oxidized oil. Full article