Investigating the Role of the PGF2 Alpha/Calcineurin-Signaling Pathway in the Regulation of Adipogenesis

Prostaglandin F2α (PGF2α) is a potent physiological inhibitor of adipocyte differentiation. In previous studies, we demonstrated that PGF2α inhibits adipogenesis via activation of the calcium-regulated protein phosphatase, calcineurin. In this current study, we have now extended these findings to identify the IL-11 cytokine and the Nurr1 orphan nuclear hormone receptor as functionally important downstream transcriptional targets of the PGF2α/calcineurin-pathway involved in the inhibition of adipocyte differentiation. In the case of IL-11, we show that this cytokine acts in an autocrine fashion to inhibit adipogenesis via the essential actions of the gp130 cytokine co-receptor signaling subunit. Further, by using a well-characterized panel of chimeric gp130 receptor mutants, we demonstrate that the activation of gp130-dependent signaling is sufficient to inhibit adipogenesis, and that the activation of the STAT1 transcription factor is necessary for this effect. Conversely, we find that the depletion of endogenous STAT1 rescues adipogenesis from the anti-adipogenic effects of both IL-11 and PGF2α. Taken together, these data provide evidence of a role for an autocrine IL-11/gp130/STAT1-dependent signaling cascade in mediating the inhibitory effects of the PGF2α/calcineurin-signaling pathway on adipogenesis. In the case of Nurr1, using a dominant-negative approach, we provide evidence that Nurr1 is also involved in mediating the inhibitory effects of PGF2α on adipogenesis. Further, using a panel of selective Nurr1 mutants, we demonstrate that the anti-adipogenic effects of Nurr1 are dependent upon its ability to directly bind DNA, but not its ability to heterodimerize with its nuclear partner protein, RXR. Additional experiments reveal that the PGF2α/calcineurin-signaling pathway induces expression of Nurr1 via the action of the CREB transcription factor, and more specifically, its association with members of the calcineurin-sensitive, CREB-regulated transcriptional co-activator (CRTC) family of proteins. Taken together, these results provide evidence that, in addition to IL-11, the CRTC/CREB/Nurr1-dependent signaling cascade also plays a role in mediating the inhibitory effects of the PGF2α/calcineurin-signaling pathway on adipogenesis. Collectively, these studies identify two parallel pathways that act in concert downstream of calcineurin to mediate the inhibitory effect of PGF2α on adipocyte differentiation, thereby affording significant new insights into the molecular mechanisms by which the PGF2α/calcineurin-signaling pathway inhibits the adipogenic process

High performance VLSI arithmetic macrocells

To investigate various techniques such as redundant arithemtic and residue number systems to produce large arithemtic functions in the form of VLSI macrocells capable of process independent reuse in systems incorporating standard on-chip bus sytems.RG 22/9

Manuka honey microneedles for enhanced wound healing and the prevention and/or treatment of Methicillin-resistant Staphylococcus aureus (MRSA) surgical site infection

© 2020, The Author(s). Manuka honey (MH) is currently used as a wound treatment and suggested to be effective in Methicillin-resistant Staphylococcus aureus (MRSA) elimination. We sought to optimize the synthesis of MH microneedles (MHMs) while maintaining the MH therapeutic effects. MHMs were synthesized using multiple methods and evaluated with in vitro assays. MHMs demonstrated excellent bactericidal activity against MRSA at concentrations ≥ 10% of honey, with vacuum-prepared honey appearing to be the most bactericidal, killing bacterial concentrations as high as 8 × 107 CFU/mL. The wound-healing assay demonstrated that, at concentrations of 0.1%, while the cooked honey had incomplete wound closure, the vacuum-treated honey trended towards faster wound closure. In this study, we demonstrate that the method of MHM synthesis is crucial to maintaining MH properties. We optimized the synthesis of MHMs and demonstrated their potential utility in the treatment of MRSA infections as well as in wound healing. This is the first report of using MH as a substrate for the formation of dissolvable microneedles. This data supports the need for further exploration of this new approach in a wound-healing model and opens the door for the future use of MH as a component of microneedle scaffolds

Identification of a new strain of mouse kidney parvovirus associated with inclusion body nephropathy in immunocompromised laboratory mice

© 2020, © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group, on behalf of Shanghai Shangyixun Cultural Communication Co., Ltd. Inclusion body nephropathy (IBN) and kidney fibrosis in aged immunodeficient mice and, to lesser extent, in immunocompetent mice have been recently linked to infection of mouse kidney parvovirus (MKPV), also known as murine chapparvovirus (MuCPV). Knowledge about its prevalence and the complete genome sequence of more MKPV strains is essential for understanding phylogenetic relationships and pathogenicity among MKPV strains. In the present study using PCR and genome walking, we determined the complete 4440-nucleotide genome of a new MKPV strain, namely MIT-WI1, which was identified in IBN-affected Il2rg-/-Rag2-/- c-Kit W-sh/W-sh mice housed in the vivarium at Whitehead Institute for Biomedical Research (WI). The overall nucleotide (>94%) and deduced amino acid sequences (>98%) of p10, p15, NS1 (replicase), NS2 and VP1 (capsid protein) within the MIT-WI1 genome, are closely related to MKPV/MuCPV strains described in laboratory and wild Mus musculus mice. In addition, PCR and qPCR assays using newly designed primers conserved among the known MKPV/MuCPV genomes were developed and utilized to assess MKPV status in selected mice. MKPV was also detected in immunodeficient (NSG) and immunocompetent (Crl:CD1(ICR), UTXflox) mouse strains/stocks. The abundance of the MKPV genome copies was significantly correlated with the severity of IBN. Our data indicate that MKPV is present in selected mouse strains/stocks, and provides new insights into the genome evolution of MKPV

Draft Genome Sequences of Klebsiella pneumoniae Strains Isolated from Immunocompromised NOD-scid Gamma Research Mice

Thirteen Klebsiella pneumoniae isolates cultured from feces, intestines, liver, lungs, and blood from immunocompromised NOD-scid gamma (NSG) mice with clinical illness, housed at a biomedical research institute, were sequenced using Illumina MiSeq technology for elucidation of pathogenic potential and genes encoding antibiotic resistance

Dietary suppression of MHC class II expression in intestinal epithelial cells enhances intestinal tumorigenesis

Little is known about how interactions of diet, intestinal stem cells (ISCs), and immune cells affect early-stage intestinal tumorigenesis. We show that a high-fat diet (HFD) reduces the expression of the major histocompatibility complex class II (MHC class II) genes in intestinal epithelial cells, including ISCs. This decline in epithelial MHC class II expression in a HFD correlates with reduced intestinal microbiome diversity. Microbial community transfer experiments suggest that epithelial MHC class II expression is regulated by intestinal flora. Mechanistically, pattern recognition receptor (PRR) and interferon-gamma (IFNγ) signaling regulates epithelial MHC class II expression. MHC class II-negative (MHC-II−) ISCs exhibit greater tumor-initiating capacity than their MHC class II-positive (MHC-II+) counterparts upon loss of the tumor suppressor Apc coupled with a HFD, suggesting a role for epithelial MHC class II-mediated immune surveillance in suppressing tumorigenesis. ISC-specific genetic ablation of MHC class II increases tumor burden cell autonomously. Thus, HFD perturbs a microbiome-stem cell-immune cell interaction that contributes to tumor initiation in the intestine

Dietary suppression of MHC class II expression in intestinal epithelial cells enhances intestinal tumorigenesis

Little is known about how interactions of diet, intestinal stem cells (ISCs), and immune cells affect early-stage intestinal tumorigenesis. We show that a high-fat diet (HFD) reduces the expression of the major histocompatibility complex class II (MHC class II) genes in intestinal epithelial cells, including ISCs. This decline in epithelial MHC class II expression in a HFD correlates with reduced intestinal microbiome diversity. Microbial community transfer experiments suggest that epithelial MHC class II expression is regulated by intestinal flora. Mechanistically, pattern recognition receptor (PRR) and interferon-gamma (IFNγ) signaling regulates epithelial MHC class II expression. MHC class II-negative (MHC-II-) ISCs exhibit greater tumor-initiating capacity than their MHC class II-positive (MHC-II+) counterparts upon loss of the tumor suppressor Apc coupled with a HFD, suggesting a role for epithelial MHC class II-mediated immune surveillance in suppressing tumorigenesis. ISC-specific genetic ablation of MHC class II increases tumor burden cell autonomously. Thus, HFD perturbs a microbiome-stem cell-immune cell interaction that contributes to tumor initiation in the intestine