1.Poly(ethylene glycol) Hydrogel Scaffolds Containing Cell-Adhesive and Protease-Sensitive Peptides Support Microvessel Formation by Endothelial Progenitor Cells.
Peters EB1, Christoforou N2, Leong KW3, Truskey GA1, West JL1. Cell Mol Bioeng. 2016 Mar 1;9(1):38-54. Epub 2015 Oct 20.
The development of stable, functional microvessels remains an important obstacle to overcome for tissue engineered organs and treatment of ischemia. Endothelial progenitor cells (EPCs) are a promising cell source for vascular tissue engineering as they are readily obtainable and carry the potential to differentiate towards all endothelial phenotypes. The aim of this study was to investigate the ability of human umbilical cord blood-derived EPCs to form vessel-like structures within a tissue engineering scaffold material, a cell-adhesive and proteolytically degradable poly(ethylene glycol) (PEG) hydrogel. EPCs in co-culture with angiogenic mural cells were encapsulated in hydrogel scaffolds by mixing with polymeric precursors and using a mild photocrosslinking process to form hydrogels with homogeneously dispersed cells. EPCs formed 3D microvessels networks that were stable for at least 30 days in culture, without the need for supplemental angiogenic growth factors.
2.Collagencin, an antibacterial peptide from fish collagen: Activity, structure and interaction dynamics with membrane.
Ennaas N1, Hammami R2, Gomaa A1, Bédard F3, Biron É3, Subirade M1, Beaulieu L4, Fliss I5. Biochem Biophys Res Commun. 2016 Mar 30. pii: S0006-291X(16)30434-X. doi: 10.1016/j.bbrc.2016.03.121. [Epub ahead of print]
In this study, we first report characterization of collagencin, an antimicrobial peptide identified from fish collagen hydrolysate. The peptide completely inhibited the growth of Staphylococcus aureus at 1.88 mM. Although non-toxic up to 470 μM, collagencin was hemolytic at higher concentrations. The secondary structure of collagencin was mainly composed by β-sheet and β-turn as determined by CD measurements and molecular dynamics. The peptide is likely to form β-sheet structure under hydrophobic environments and interacts with both anionic (phosphatidylglycerol) and zwitterionic (phosphoethanolamine and phosphatidylcholine) lipids as shown with CD spectroscopy and molecular dynamics. The peptide formed several hydrogen bonds with both POPG and POPE lipids and remained at membrane-water interface, suggesting that collagencin antibacterial action follows a carpet mechanism. Collagenous fish wastes could be processed by enzymatic hydrolysis and transformed into products of high value having functional or biological properties.
3.The dipeptidyl peptidase inhibitor linagliptin and the angiotensin II receptor blocker telmisartan show renal benefit by different pathways in rats with 5/6 nephrectomy.
Tsuprykov O1, Ando R2, Reichetzeder C1, von Websky K1, Antonenko V1, Sharkovska Y3, Chaykovska L4, Rahnenführer J1, Hasan AA5, Tammen H6, Alter M7, Klein T8, Ueda S9, Yamagishi S10, Okuda S2, Hocher B11. Kidney Int. 2016 May;89(5):1049-61. doi: 10.1016/j.kint.2016.01.016. Epub 2016 Mar 24.
Dipeptidyl peptidase (DPP)-4 inhibitors delay chronic kidney disease (CKD) progression in experimental diabetic nephropathy in a glucose-independent manner. Here we compared the effects of the DPP-4 inhibitor linagliptin versus telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. Animals were allocated to 1 of 4 groups: sham operated plus placebo; 5/6 nephrectomy plus placebo; 5/6 nephrectomy plus linagliptin; and 5/6 nephrectomy plus telmisartan. Interstitial fibrosis was significantly decreased by 48% with linagliptin but a non-significant 24% with telmisartan versus placebo. The urine albumin-to-creatinine ratio was significantly decreased by 66% with linagliptin and 92% with telmisartan versus placebo. Blood pressure was significantly lowered by telmisartan, but it was not affected by linagliptin. As shown by mass spectrometry, the number of altered peptide signals for linagliptin in plasma was 552 and 320 in the kidney.
4.Regulating Inflammatory Immune Response to Atherogenic Antigens Prevents Development and Progression of Atherosclerosis in New Zealand White Rabbits.
Philip S1, Ponnusamy T2, Rao LN2, Biradar S1, Kumar R1, Deshpande V1, Lu X3, Kakkar VV4, Mundkur LA5. Can J Cardiol. 2015 Oct 22. pii: S0828-282X(15)01491-9. doi: 10.1016/j.cjca.2015.09.022. [Epub ahead of print]
BACKGROUND: Inflammatory immune response to atherogenic self-antigens plays an important role in the development of atherosclerosis. We evaluated the role of oral tolerance to three peptides in controlling atherosclerosis in New Zealand white rabbits.