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Simple Summary: p53 isoforms have been reported in various tumor types. Both p53β and p53γ were recently reported to retain functionalities of full-length p53α. A role for p53 and p53 loss in cholesterol metabolism has also emerged. We show that SMG1, a phosphatidylinositol 3-kinase-related kinase, when inhibited in p53 wild-type MCF7 and HepG2 cells, significantly alters the expression of cholesterol pathway genes, with a net increase in intracellular cholesterol and an increased sensitivity to Fatostatin in MCF7. We confirm a prior report that SMG1 inhibition in MCF7 cells promotes expression of p53β and show the first evidence for increases in p53γ. Further, induced p53β expression, confirmed with antibody, explained the loss of SMG1 upregulation of the ABCA1 cholesterol exporter where p53γ had no effect on ABCA1. Additionally, upregulation of ABCA1 upon SMG1 knockdown was independent of upregulation of nonsense-mediated decay target RASSF1C, previously suggested to regulate ABCA1 via a "RASSF1C-miR33a-ABCA1" axis. SMG1, a phosphatidylinositol 3-kinase-related kinase (PIKK), essential in nonsense-mediated RNA decay (NMD), also regulates p53, including the alternative splicing of p53 isoforms reported to retain p53 functions. We confirm that SMG1 inhibition in MCF7 tumor cells induces p53β and show p53γ increase. Inhibiting SMG1, but not UPF1 (a core factor in NMD), upregulated several cholesterol pathway genes. SMG1 knockdown significantly increased ABCA1, a cholesterol efflux pump shown to be positively regulated by full-length p53 (p53α). An investigation of RASSF1C, an NMD target, increased following SMG1 inhibition and reported to inhibit miR-33a-5p, a canonical ABCA1-inhibiting miRNA, did not explain the ABCA1 results. ABCA1 upregulation following SMG1 knockdown was inhibited by p53β siRNA with greatest inhibition when p53α and p53β were jointly suppressed, while p53γ siRNA had no effect. In contrast, increased expression of MVD, a cholesterol synthesis gene upregulated in p53 deficient backgrounds, was sensitive to combined targeting of p53α and p53γ. Phenotypically, we observed increased intracellular cholesterol and enhanced sensitivity of MCF7 to growth inhibitory effects of cholesterol-lowering Fatostatin following SMG1 inhibition. Our results suggest deregulation of cholesterol pathway genes following SMG1 knockdown may involve alternative p53 programming, possibly resulting from differential effects of p53 isoforms on cholesterol gene expression. [ABSTRACT FROM AUTHOR]

Abstract The present study was conducted to evaluate the effects of dietary flavonoids from Allium mongolicum Regel (AMRF) supplementation on growth, antioxidant and immune status, immune-related genes expression and disease resistance in Channa argus. A basal diet was supplemented with AMRF at 0, 10, 20 or 40 mg/kg feed for 56 days. The result revealed that weight gain (WG) and specific growth rate (SGR) were significantly increased (P <.05) with the increase of dietary AMRF levels from 0 to 40 mg/kg. All AMRF-supplemented groups (10, 20 or 40 mg/kg) significantly enhanced (P <.05) serum AKP, lysozyme activity, C3, IgM concentration, liver antioxidant enzymes activity (SOD, CAT and GSH-Px) or decreased (P <.05) serum cortisol, liver MDA content, serum ALT and AST activity. Meanwhile, AMRF administration significantly up-regulated (P <.05) the expression of SOD, IgM, HSP70, HSP90, IκB-α and GR or down-regulated (P <.05) NF-κB p65 and inflammatory cytokines (TNF-α, IL-1β and IL-8) transcription in head kidney of C. argus. After challenge with Aeromonas hydrophila , survival rates in all AMRF treatment groups were significantly increased (P <.05). These results indicated that dietary intake containing AMRF enhanced growth, antioxidant and immune response and regulated immune-related genes expression and increased disease resistance against Aeromonas hydrophila in snakehead fish, with greatest effects in fish given 40 mg/kg AMRF for 56 days. Highlights • Flavonoids from Allium mongolicum Regel enhanced growth, antioxidant and immune response of snakehead fish. • Flavonoids from Allium mongolicum Regel regulated immune-related genes expression in snakehead fish. • Flavonoids from Allium mongolicum Regel enhanced the disease resistance against Aeromonas hydrophila in snakehead fish. • The optimum supplemented dose of flavonoids from Allium mongolicum Regel is 40 mg/kg. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of dietary coated sodium butyrate (CSB) on lipopolysaccharide (LPS)-induced inflammatory response in weaned lambs. A basal diet was supplemented with CSB at 0, 2 or 3 g/kg feed for 28 days and/or intraperitoneally injected with 100 μg/kg BW Escherichia coli LPS (0 g/kg CSB, 0 g/kg CSB and LPS, 2 g/kg CSB and LPS, 3 g/kg CSB and LPS). The results showed that CSB supplementation conferred significant protective effects against LPS-induced inflammatory response by reducing in the levels of D-lactate (DLA), diamine oxidase (DAO), inflammatory cytokines (TNF-α, IL-1β and IL-8) in the serum and upregulated expression of tight junction proteins (claudin-3, ZO-1 and occludin) in the ileum. Meanwhile, CSB pre-treatment significantly suppressed LPS-induced TLR4/NF-κB signalling pathway mRNA expression (MyD88, TLR4, NF-κB, IL-6 and IL-1β) and down-regulated TLR4/NF-κB signalling pathway protein expression (MyD88, TLR4, NF-κB p65 and p-NF-κB p65). Furthermore, dietary CSB supplementation improved intestinal morphology. Lastly, bacterial 16S rRNA gene sequencing indicated that CSB could alter intestinal microbiota composition at genus levels. Taken together, our results indicate CSB could maintain intestinal health, improve intestinal morphology, modulate the microbial community and decrease LPS-induced inflammatory response in lambs. The addition of CSB improves the permeability of lamb's intestinal tract The addition of CSB enhances lamb's intestinal barrier function CSB alter intestinal microbiota composition at genus levels CSB alleviates LPS-induced intestinal injury in weaned lambs through TLR4/NF-κB signalling pathway [ABSTRACT FROM AUTHOR]

Aim: Since ILT3Fc induces the upregulation of BCL6, DUSP10 and SOCS1 via downregulation of miRNA in T suppressor cells, we investigated the possibility that this molecule also inhibits TCR signaling and nuclear localization of transcription factors. Methods: Signaling studies were performed using Jurkat cells stimulated with CD3/CD28 monoclonal antibodies or PMA for various periods of time in the presence or absence of ILT3Fc. Western blots were used to analyze total cell lysates or nuclear fractions, using antibodies recognizing TCR signaling proteins or TCR-activated transcription factors. Results: The Jurkat cell line is similar to activated human T lymphocytes and shows high binding of ILT3Fc (>90%), representing an ideal tool for studying signaling events downstream of the ILT3 ligand. We found that micro RNA gene promoters can be activated by anti-CD3/CD28 mAbs in Jurkat cells and are inhibited by treatment with ILT3Fc. Mutations at the AP1 binding sites in the miR-21 and miR-155 gene promoters abolished reporter gene activity. ILT3Fc consistently inhibited PMA-induced reporter activities, demonstrating that AP1 is crucial to the inhibitory effect of ILT3Fc. Nuclear fractions of cell extracts obtained from activated Jurkat cells were probed for various subunits of the AP-1 protein complexes. ILT3Fc inhibited and delayed TCR signaling events such as cFOS and FOSB synthesis and translocation into the nucleus. Conclusions: These results indicate that the inhibitory activity of ILT3Fc is mediated through its effect of TCR signaling during the very early stages of T cell activation. This finding that ILT3Fc regulates miRNA transcriptionally by targeting TCR/AP1 signaling pathways indicates that this agent raises the threshold of TCR triggering inducing anergy. This phenomenon in conjunction with the capacity of ILT3Fc to inhibit several micro RNA explains the strong immunomodulatory activity of ILT3Fc, a reliable inducer of regulatory T cells and transplantation tolerance. [Copyright &y& Elsevier]