cs1-peptide and Disease-Models--Animal

Mechanical pain hypersensitivity associated with physical trauma to peripheral nerve depends on T-helper (Th) cells expressing the algesic cytokine, interleukin (IL)-17A. Fibronectin (FN) isoform alternatively spliced within the IIICS region encoding the 25-residue-long connecting segment 1 (CS1) regulates T cell recruitment to the sites of inflammation. Herein, we analyzed the role of CS1-containing FN (FN-CS1) in IL-17A expression and pain after peripheral nerve damage.. Mass spectrometry, immunoblotting, and FN-CS1-specific immunofluorescence analyses were employed to examine FN expression after chronic constriction injury (CCI) in rat sciatic nerves. The acute intra-sciatic nerve injection of the synthetic CS1 peptide (a competitive inhibitor of the FN-CS1/α4 integrin binding) was used to elucidate the functional significance of FN-CS1 in mechanical and thermal pain hypersensitivity and IL-17A expression (by quantitative Taqman RT-PCR) after CCI. The CS1 peptide effects were analyzed in cultured primary Schwann cells, the major source of FN-CS1 in CCI nerves.. Following CCI, FN expression in sciatic nerve increased with the dominant FN-CS1 deposition in endothelial cells, Schwann cells, and macrophages. Acute CS1 therapy attenuated mechanical allodynia (pain from innocuous stimulation) but not thermal hyperalgesia and reduced the levels of IL-17A expression in the injured nerve. CS1 peptide inhibited the LPS- or starvation-stimulated activation of the stress ERK/MAPK pathway in cultured Schwann cells.. After physical trauma to the peripheral nerve, FN-CS1 contributes to mechanical pain hypersensitivity by increasing the number of IL-17A-expressing (presumably, Th17) cells. CS1 peptide therapy can be developed for pharmacological control of neuropathic pain.

Topics: Animals; Animals, Newborn; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Cells, Cultured; Disease Models, Animal; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Female; Hyperalgesia; Intercellular Signaling Peptides and Proteins; Interleukin-17; Pain Measurement; Peptides; Rats; Rats, Sprague-Dawley; Schwann Cells; Sciatic Nerve; Sciatic Neuropathy; Time Factors

To compare the effects of postprandial hypertriglyceridemia and postprandial hyperglycemia on monocyte adhesion to endothelial cells, we investigated the effects of twice-daily standard diet (5% fat) and high-fat diet (30% fat) for 3 weeks on monocyte adhesion to endothelial cells and the expression of adhesion molecules in the aortic artery in non-obese type 2 diabetic Goto-Kakizaki rats. Fasting glucose, insulin, non-esterified fatty acid (NEFA), HbA1c, and body weight were comparable between the two diet groups. Postprandial glucose and insulin were higher in the standard diet group, while postprandial NEFA and triglyceride were higher in the high fat diet group, compared with the other group. The number of monocyte adherent to endothelial cells was higher in the high-fat diet group than the standard diet group. Consumption of high-fat diet resulted in overexpression of heme oxygenase-1, intercellular adhesion molecule-1 (ICAM-1), and connecting segment-1 fibronectin on the arterial wall, compared with standard diet. Thus, our data demonstrated that short-term intermittent high-fat diet prevented postprandial hyperglycemia in a model of type 2 diabetes without a significant increase in body weight. However, the resulting postprandial hypertriglyceridemia induces more monocyte adhesion to endothelial cells than postprandial hyperglycemia. This increased monocyte adhesion is associated with the increased aortic expression of adhesion molecules such as ICAM-1, and connecting segment-1 fibronectin.

Topics: Animals; Aorta; Blood Glucose; Cell Adhesion; Diabetes Mellitus, Type 2; Dietary Fats; Disease Models, Animal; Endothelium, Vascular; Fatty Acids, Nonesterified; Glycated Hemoglobin; Heme Oxygenase-1; Hyperglycemia; Hypertriglyceridemia; Insulin; Intercellular Adhesion Molecule-1; Intercellular Signaling Peptides and Proteins; Male; Monocytes; Peptides; Postprandial Period; Rats; Rats, Inbred Strains; Triglycerides

We investigated the effects of the connecting segment-1 (CS1) peptide, which blocks fibronectin (FN)-alpha4beta1 integrin interactions, upon recipient survival and extent of tissue injury in a well-established rat liver model of ex vivo 24-hour cold ischemia followed by isotransplantation. In this model, CS1 peptides were administered through the portal vein of rat livers prior to and after cold ischemic storage. In addition, recipients of orthotopic liver transplants (OLT) received a dose of CS1 peptides 1 hour post-OLT. CS1 peptide therapy significantly inhibited the intragraft recruitment of T lymphocytes and neutrophil activation/infiltration, and repressed important mediators of inflammation, such as cyclooxygenase-2, and inducible nitric oxide synthase expression. Importantly, CS1 peptide therapy improved function/histological preservation of liver grafts and extended their 14-day survival from 50% in control to 100% in CS1-treated OLTs. Thus, CS1 peptide-mediated blockade of FN-alpha4beta1 interaction protects against severe ischemia-reperfusion injury experienced otherwise by OLTs. These novel findings document the potential of targeting FN-alpha4beta1 in vivo interaction for improving OLT outcomes.

Topics: Animals; Disease Models, Animal; Gene Expression Regulation, Enzymologic; Graft Survival; Integrin alpha4beta1; Intercellular Signaling Peptides and Proteins; Liver Circulation; Liver Transplantation; Male; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Peptides; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction