PPAR-dependent bioluminescence in living mice and individual organs after chitosan administration.

<p>(A) Time course. Transgenic mice were subcutaneously injected saline (mock) or chitosan, and images at indicated periods. Results are expressed as relative intensity, which is presented as comparison with the luminescent intensity relative to mock. Values are mean ± standard error (<i>n</i>=6 per group). (B) <i>Ex vivo</i> imaging and quantification of photon emission from individual organs. Transgenic mice were subcutaneously injected saline (mock) or chitosan, and sacrificed 3 days later for organ imaging. Values are mean ± standard error (<i>n</i>=6 per group). *<i>p</i><0.05, ***<i>p</i><0.001, compared with mock. The color overlay on the image represents the photon/sec emitted from the organs, as indicated by the color scale. Photos are representative images.</p

Construction and optimization of PPRE reporter constructs.

<p>(A) The schematic diagram of PPRE reporter constructs. Two PPRE oligonucleotides were annealed and ligated to form various tandem repeats of PPRE. The resulting products were analyzed by 8% polyacrylamide gels (left panel). Eight reporter constructs containing various numbers of PPREs were shown on the right. (B) Effect of rosiglitazone on the inducibility of PPRE reporter constructs. HepG2 cells were transiently transfected with PPRE constructs and pcDNA3.1/lacZ DNA, and treated without or with 0.5 µM rosiglitazone. Luciferase and β-galactosidase activities were determined 24 hours later. Luciferase activities are expressed as induction fold, which is presented as comparison with RLU related to untreated cells. β-Galactosidase activities are expressed as OD420. Values are mean ± standard error of three independent assays. **<i>p</i><0.01, ***<i>p</i><0.001, compared with untreated cells. (C) <i>In vitro</i> imaging. HepG2 cells were transiently transfected with PPRE constructs containing 5 tandem repeats of PPRE and treated without or with 0.5 µM rosiglitazone. Luciferase activity was imaged at 24 h by IVIS system. The color overlay on the image represents the photon/sec emitted from the cells, as indicated by the color scale. Quantification of photon emission from the cells was shown at the bottom. Values are mean ± standard error of three independent assays. ***<i>p</i><0.001, compared with mock. Photos are representative images.</p

Classification of chitosan-regulated genes in the brain by KEGG pathways.

a<p>“Observed" means the number of genes regulated by chitosan in this pathway. “Total" means the total number of genes in this pathway.</p>b<p><i>p</i>-Value was calculated on WebGestalt web site (<a href="http://bioinfo.vanderbilt.edu/webgestalt/login.php" target="_blank">http://bioinfo.vanderbilt.edu/webgestalt/login.php</a>) by hypergeometric test.</p

Classification of chitosan-regulated genes in the stomach by KEGG pathways.

a<p>“Observed" means the number of genes regulated by chitosan in this pathway. “Total" means the total number of genes in this pathway.</p>b<p><i>p</i>-Value was calculated on WebGestalt web site (<a href="http://bioinfo.vanderbilt.edu/webgestalt/login.php" target="_blank">http://bioinfo.vanderbilt.edu/webgestalt/login.php</a>) by hypergeometric test.</p

Corn Silk Extract and Its Bioactive Peptide Ameliorated Lipopolysaccharide-Induced Inflammation in Mice via the Nuclear Factor-κB Signaling Pathway

Bioactive peptides derived from foods have shown beneficial anti-inflammatory potential. Inhibitory κB kinase-β (IKKβ) plays a crucial role in the activation of nuclear factor-κB (NF-κB), a transcription factor involved in inflammation. Here we applied proteomic and bioinformatics approaches to identify anti-inflammatory peptides that target IKKβ from corn silk. Corn silk extract significantly suppressed lipopolysaccharide (LPS)-induced NF-κB activities [(1.7 ± 0.2)-fold vs (3.0 ± 0.6)-fold, <i>p</i> < 0.05] in cells. Trypsin hydrolysate of corn silk also suppressed LPS-induced NF-κB activities [(1.1 ± 0.3)-fold vs 3.3 ± 0.5 fold, <i>p</i> < 0.01]. In addition, both corn silk extract and trypsin hydrolysate significantly inhibited LPS-induced interleukin-1β (IL-1β) production by 58.3 ± 4.5 and 55.1 ± 7.4%, respectively. A novel peptide, FK2, docked into the ATP-binding pocket of IKKβ, was further identified from trypsin hydrolysis of corn silk. FK2 inhibited IKKβ activities, IκB phosphorylation, and subsequent NF-κB activation [(2.3 ± 0.4)-fold vs (5.5 ± 0.4)-fold, <i>p</i> < 0.001]. Moreover, FK2 significantly reduced NF-κB-driven luminescent signals in organs by 5–11-fold and suppressed LPS-induced NF-κB activities and IL-β production in tissues. In conclusion, our findings indicated that corn silk displayed anti-inflammatory abilities. In addition, we first identified an anti-inflammatory peptide FK2 from corn silk. Moreover, the anti-inflammatory effect of FK2 might be through IKKβ–NF-κB signaling pathways

Momordica charantia and Its Novel Polypeptide Regulate Glucose Homeostasis in Mice via Binding to Insulin Receptor

Momordica charantia (MC) has been used as an alternative therapy for diabetes mellitus. This study analyzed and elucidated therapeutic targets contributing to the hypoglycemic effect of aqueous extract of MC seeds (MCSE) by transcriptomic analysis. Protein ingredients aimed at the hypoglycemic target were further identified by proteomic, docking, and receptor-binding assays. The data showed that MSCE (1 g/kg) significantly lowered the blood glucose level in normal and diabetic mice. Moreover, MCSE primarily regulated the insulin signaling pathway in muscles and adipose tissues, suggesting that MCSE might target insulin receptor (IR), stimulate the IR-downstream pathway, and subsequently display hypoglycemic activity in mice. It was further revealed that inhibitor against trypsin (TI) of MC directly docked into IR and activated the kinase activity of IR in a dose-dependent manner. In conclusion, the findings suggested that MCSE regulated glucose metabolism mainly via the insulin signaling pathway. Moreover, TI was newly identified as a novel IR-binding protein of MC that triggered the insulin signaling pathway via binding to IR

Immunohistochemical staining of 5-FU-treated oral mucosa.

<p>Mice were treated with 5-FU and oral mucosa was collected 5 weeks later. Sections of oral mucosa were stained with antibodies against CD11b, IL-1β, TNF-α, or Bglap-rs1. (A) Immunohistochemical staining (200× magnification). Photos are representative images (n = 5 /group). (B) Quantitation of photos. Results are expressed as area (%). Values are mean ± standard error (n = 5 /group). *<i>p</i><0.05, **<i>p</i><0.01, ***<i>p</i><0.001, compared with the control group (mock).</p

KEGG pathway analysis of genes in oral mucosa at the 5^th week after intraperitoneally administered with 5-FU.

<p>^a Genes with fold changes >2.0 or ≤-2.0 were analyzed by KEGG pathways</p><p>^b<i>p</i> values were calculated by the geneSetTest function implemented in the limma package</p><p>KEGG pathway analysis of genes in oral mucosa at the 5^th week after intraperitoneally administered with 5-FU.</p

The expression levels of significantly changed genes induced by 5-FU in oral mucositis.

<p>The expression levels of significantly changed genes induced by 5-FU in oral mucositis.</p

A Novel Insulin Receptor-Binding Protein from <i>Momordica charantia</i> Enhances Glucose Uptake and Glucose Clearance in Vitro and in Vivo through Triggering Insulin Receptor Signaling Pathway

Diabetes, a common metabolic disorder, is characterized by hyperglycemia. Insulin is the principal mediator of glucose homeostasis. In a previous study, we identified a trypsin inhibitor, named <i>Momordica charantia</i> insulin receptor (IR)-binding protein (mcIRBP) in this study, that might interact with IR. The physical and functional interactions between mcIRBP and IR were clearly analyzed in the present study. Photo-cross-linking coupled with mass spectrometry showed that three regions (17–21, 34–40, and 59–66 residues) located on mcIRBP physically interacted with leucine-rich repeat domain and cysteine-rich region of IR. IR-binding assay showed that the binding behavior of mcIRBP and insulin displayed a cooperative manner. After binding to IR, mcIRBP activated the kinase activity of IR by (5.87 ± 0.45)-fold, increased the amount of phospho-IR protein by (1.31 ± 0.03)-fold, affected phosphoinositide-3-kinase/Akt pathways, and consequently stimulated the uptake of glucose in 3T3-L1 cells by (1.36 ± 0.12)-fold. Intraperitoneal injection of 2.5 nmol/kg mcIRBP significantly decreased the blood glucose levels by 20.9 ± 3.2% and 10.8 ± 3.6% in normal and diabetic mice, respectively. Microarray analysis showed that mcIRBP affected genes involved in insulin signaling transduction pathway in mice. In conclusion, our findings suggest that mcIRBP is a novel IRBP that binds to sites different from the insulin-binding sites on IR and stimulates both the glucose uptake in cells and the glucose clearance in mice