Potentiating cutaneous wound healing in young and aged skin with nutraceutical collagen peptides.

BACKGROUND: Chronic wounds continue to be a burden to healthcare systems, with ageing linked to increased prevalence of chronic wound development. Nutraceutical collagen peptides have been shown to reduce signs of skin ageing, but their therapeutic potential for cutaneous wound healing remains undefined. AIM: To determine the potential for nutraceutical collagen peptides to promote cutaneous wound healing in vitro in the context of age. METHODS: The potential for bovine- or porcine-derived nutraceutical collagen peptides to promote wound healing of primary cutaneous fibroblasts and keratinocytes derived from young and aged individuals in vitro was assessed by two-dimensional scratch and cell-viability assays and by immunofluorescence for the cell proliferation marker, Ki67. The achievement of peptide concentrations in vivo, equivalent to those exerting a beneficial effect on wound healing in vitro, was confirmed by pharmacokinetic studies of hydroxyproline, a biomarker for collagen peptide absorption, following peptide ingestion by healthy individuals over a wide age range. RESULTS: Results demonstrated significant nutraceutical collagen peptide-induced wound closure of both young and aged fibroblasts and keratinocytes, mediated by enhanced cellular proliferation and migration. Analysis of blood levels of hydroxyproline in young and aged individuals following porcine collagen peptide ingestion revealed peak serum/plasma levels after 2 h at similar concentrations to those exerting beneficial effects on wound healing in vitro. CONCLUSION: These data demonstrate the capacity for nutraceutical collagen peptides to promote cutaneous wound closure in vitro, at pharmacologically achievable concentrations in vivo, thereby offering a potential novel therapeutic strategy for the management of cutaneous wounds in young and aged individuals.

A mini-review of mass spectrometry using high-performance FTICR-MS methods.

Structural characterization of macromolecules is currently delivering new insights into the behavior of individual molecules or molecular ensembles. Technological advances have made it possible to examine smaller and smaller amounts (down to single molecules) of larger and larger molecular systems. Mass spectrometry in particular is capable of the detailed study of extremely small quantities (down to a single molecule) of very large (biological) molecules. The advent of new ionization techniques such as electrospray and matrix-assisted laser desorption are mainly responsible for these advances. As a result, mass spectrometry has evolved into an enabling discipline that plays an increasingly important role in combinatorial chemistry, polymer science, biochemistry, medicine, environmental and marine science, and archaeology and conservation science. This paper will review a selection of methodological developments in the field of high-performance Fourier transform ion cyclotron resonance mass spectrometry for structural analysis of these macromolecules.

Clofibrate-induced relocation of phosphatidylcholine transfer protein to mitochondria in endothelial cells.

The phosphatidylcholine transfer protein (PC-TP) is a specific transporter of phosphatidylcholine (PC) between membranes. To get more insight into its physiological function, we have studied the localization of PC-TP by microinjection of fluorescently labeled PC-TP in foetal bovine heart endothelial (FBHE) cells and by expression of an enhanced yellow fluorescent protein-PC-TP fusion protein in FBHE cells, human umbilical vein endothelial cells, and HepG2 cells. Analysis by confocal laser scanning microscopy showed that PC-TP was evenly distributed throughout the cytosol with an apparently elevated level in nuclei. By measuring the fluorescence recovery after bleaching it was established that PC-TP is highly mobile throughout the cell, with its transport into the nucleus being hindered by the nuclear envelope. Given the proposed function of PC-TP in lipid metabolism, we have tested a number of compounds (phorbol ester, bombesin, A23187, thrombin, dibutyryl cyclic AMP, oleate, clofibrate, platelet-derived growth factor, epidermal growth factor, and hydrogen peroxide) for their ability to affect intracellular PC-TP distribution. Only clofibrate (100 microM) was found to have an effect, with PC-TP moving to mitochondria within 5 min of stimulation. This relocation did not occur with PC-TP(S110A), lacking the putative protein kinase C (PKC)-dependent phosphorylation site, and was restricted to the primary endothelial cells. Relocation did not occur in HepG2 cells, possibly due to the fact that clofibrate does not induce PKC activation in these cells.

The early glycation products of the Maillard reaction: mass spectrometric characterization of novel imidazolidinones derived from an opioid pentapeptide and glucose.

Glucose-substituted imidazolidinones related to the endogenous opioid peptide leucine-enkephalin have been investigated using fast atom bombardment tandem mass spectrometry (FAB-MS/MS) and electrospray ionization tandem mass spectrometry (ESI-MS/MS). In addition to Amadori compounds, the studied imidazolidinones represent a novel type of the early glycation products formed in the Maillard reaction. To obtain insight into the fragmentation behavior of these carbohydrate-peptide adducts, we also studied synthetic precursors of the glucose-substituted imidazolidinones as well as the corresponding isopropylidene derivatives. The collision-induced dissociation (CID) spectra of [M + H](+) ions of all these imidazolidinones have been compared. Detailed analysis showed that fragmentation of each compound generates two ions at m/z 566 and m/z 598 which are characteristic and undoubtedly confirm the imidazolidinone-type structure. These two significant ions were identified as the M + 10 and M + 42 modifications of the N-terminus of the parent opioid pentapeptide effected by the carbohydrate moiety. Furthermore, the ion at m/z 178 is identified as the M + 42 modification of the immonium ion of the N-terminal amino acid (tyrosine) also effected by the carbohydrate moiety. They can be used as diagnostic ions for imidazolidinone-type compounds in studying the Maillard reaction. Thus, we have demonstrated the utility of FAB-MS/MS and ESI-MS/MS in the structural determination and identification of such novel peptide-carbohydrate adducts, useful in understanding the details of the mechanism of non-enzymatic glycation in vivo.