H-Arg-Gly-Asp-Cys-OH is a tetrapeptide that contains the arginine-glycine-aspartate (RGD) motif, a sequence that acts as a recognition site for various adhesion proteins.1It inhibits the binding of fibrinogen to endothelial cells and ADP-stimulated platelets with IC50values of 320 and 35 μM, respectively.2Implantation of titanium rods coated with H-Arg-Gly-Asp-Cys-OH increases bone formation in rat femurs.3H-Arg-Gly-Asp-Cys-OH has been conjugated to polyethylenimine to improve gene transfection efficiency.4
1.Park, H.S., Kim, C., and Kang, Y.K.Preferred conformations of RGDX tetrapeptides to inhibit the binding of fibrinogen to plateletsBiopolymers63(5)298-313(2002) 2.Tranqui, L., Andrieux, A., Hudry-Clergeon, G., et al.Differential structural requirements for fibrinogen binding to platelets and to endothelial cellsJ. Cell Biol.108(6)2519-2527(1989) 3.Ferris, D.M., Moodie, G.D., Dimond, P.M., et al.RGD-coated titanium implants stimulate increased bone formation in vivoBiomaterials20(23-24)2323-2331(1999) 4.Kunath, K., Merdan, T., Hegener, O., et al.Integrin targeting using RGD-PEI conjugates for in vitro gene transferJ. Gene Med.5(7)588-599(2003)
Neuromedin U (NMU) is a neuropeptide first demonstrated to drive smooth muscle contraction.1Translated as a 174 amino acid propeptide, NMU is cleaved to different lengths in different animals. It has diverse receptor-mediated rolesin vivo, as it regulates feeding, vasoconstriction, nociception, and bone remodeling and contributes to obesity, cancer and septic shock.2,2NMU-25 is the active form of NMU in humans. It binds with high affinity to receptors on human left ventricle and coronary artery (KDs = 0.26 and 0.11 nM, respectively), eliciting endothelium-independent vasoconstriction.3NMU-25 also suppresses glucose-stimulated insulin secretion in human islets, and this effect is lost in NMU R165W mutants, resulting in early-onset obesity.4
1.Mitchell, J.D., Maguire, J.J., and Davenport, A.P.Emerging pharmacology and physiology of neuromedin U and the structurally related peptide neuromedin SBritish Journal of Pharmacology15887-103(2009) 2.Greenwood, H.C., Bloom, S.R., and Murphy, K.G.Peptides and their potential role in the treatment of diabetes and obesityRev.Diabet.Stud.8(3)355-368(2011) 3.Mitchell, J.D., Maguire, J.J., Kuc, R.E., et al.Expression and vasoconstrictor function of anorexigenic peptides neuromedin U-25 and S in the human cardiovascular systemCardiovascular Research81353-361(2009) 4.Alfa, R.W., Park, S., Skelly, K.R., et al.Suppression of insulin production and secretion by a decretin hormoneCell Metabolism21(2)323-333(2015)
9(Z),11(E)-Conjugated linoleic acid is an isomer of linoleic acid that has been found in beef and milk fat.1It binds to peroxisome proliferator-activated receptor α (PPARα; IC50= 140 nM) and activates the receptor in a reporter assay using COS-1 cells expressing mouse PPARα when used at a concentration of 100 μM.29(Z),11(E)-Conjugated linoleic acid inhibits TNF-α-inducedGLUT4expression and increases insulin-stimulated glucose transport in 3T3-L1 adipocytes.3Dietary administration of 9(Z)11(E)-conjugated linoleic acid reduces serum fasting glucose, insulin, and triglyceride levels and decreases white adipose tissue macrophage infiltration inob/obmice. It also increases body weight gain and body fat in weanling mice.4[Matreya, LLC. Catalog No. 1278]
1.Shultz, T.D., Chew, B.P., Seaman, W.R., et al.Inhibitory effect of conjugated dienoic derivatives of linoleic acid and β-carotene on the in vitro growth of human cancer cellsCancer Lett.63(2)125-133(1992) 2.Moya-Camarena, S.Y., Heuvel, J.P.V., Blanchard, S.G., et al.Conjugated linoleic acid is a potent naturally occurring ligand and activator of PPARαJ. Lipid Res.40(8)1426-1433(1999) 3.Moloney, F., Toomey, S., Noone, E., et al.Antidiabetic effects of cis-9, trans-11-conjugated linoleic acid may be mediated via anti-inflammatory effects in white adipose tissueDiabetes56(3)574-582(2007) 4.Pariza, M.W., Park, Y., and Cook, M.E.The biologically active isomers of conjugated linoleic acidProg. Lipid Res.40(4)283-298(2001)
Ac-VEID-AMC is a fluorogenic substrate based on the caspase-6 cleavage site in lamin A at amino acids VEID during apoptosis.1It has also been reported to be cleaved by related proteases, including caspase-8.2Caspase activity can be quantified by fluorescent detection of free AMC (also known as 7-amino-4-methylcoumarin), which is excited at 340-360 nm and emits at 440-460 nm.
1.Talanian, R.V., Quinlan, C., Trautz, S., et al.Substrate specificities of caspase family proteasesJ. Biol. Chem.272(15)9677-9682(1997) 2.Chae, H.J., Park, K.M., Lee, G.Y., et al.Je-Chun-Jun induced apoptosis of human cervical carcinoma HeLa cellsActa Pharmacologica Sinica25(10)1372-1379(2004)
Pal-KTTKS is a lipidated pentapeptide consisting of a fragment of the type I collagen C-terminal propeptide conjugated to palmitic acid .1 It increases collagen production in human corneal and dermal fibroblasts when used at concentrations of 0.002, 0.004, and 0.008 wt%.2 Following topical administration, pal-KTTKS (50 μg/cm2) is found in the stratum corneum, epidermis, and dermis of isolated hairless mouse skin.1 It can self-assemble into flat tapes and extended fibrillar structures.3 Pal-KTTKS has been detected in anti-wrinkle creams.4
|1. Choi, Y.L., Park, E.J., Kim, E., et al. Dermal stability and in vitro skin permeation of collagen pentapeptides (KTTKS and palmitoyl-KTTKS). Biomol. Ther. (Seoul) 22(4), 321-327 (2014).|2. Jones, R.R., Castelletto, V., Connon, C.J., et al. Collagen stimulating effect of peptide amphiphile C16-KTTKS on human fibroblasts. Mol. Pharm. 10(3), 1063-1069 (2013).|3. Castelletto, V., Hamley, I.W., Whitehouse, C., et al. Self-assembly of palmitoyl lipopeptides used in skin care products. Langmuir 29(29), 9149-9155 (2013).|4. Chirita, R.-I., Chaimbbault, P., Archambault, J.-C., et al. Development of a LC-MS/MS method to monitor palmitoyl peptides content in anti-wrinkle cosmetics. Anal. Chim. Acta 641(1-2), 95-100 (2009).