Specific effects of fibrinogen and the γA and γ'-chain fibrinogen variants on angiogenesis and wound healing

Single-particle fibrinogen detection using platelet membrane-coated fluorescent polystyrene nanoparticles

Fibrinogen participates in many physiological processes and is a biomarker for a variety of diseases. On this account, the development of a sensitive method for fibrinogen assay is particularly important. Herein, we demonstrate a new color-coded single-particle detection (SPD) method for fibrinogen detection by using platelet membrane-coated fluorescent polystyrene nanoparticles (PNPs) as the probes. Due to the specific interactions between fibrinogen and integrin receptors on platelet membranes, PNPs can form aggregated structures in the presence of fibrinogen. Therefore, colocalization events between green and red PNPs and the corresponding Pearson's correlation coefficient vary with the concentrations of fibrinogen. The sensing ability shows a linear range of 30-300 μg mL^-1 and a limit of detection (LOD) of 3.9 μg mL^-1 (11.3 nM) for fibrinogen detection. Moreover, it has been validated that the proposed biosensor can selectively detect fibrinogen and shows a good performance in real sample applications.

In vitro protective effects of marine-derived Aspergillus puulaauensis TM124-S4 extract on H2O2-stressed primary human fibroblasts

Nowadays, there is a huge interest in natural products obtained from marine organisms that can promote human health.The aim of the present study is to evaluate for the first time, the in vitro effects of marine Aspergillus puulaauensis TM124-S4 extract against oxidative stress in human fibroblasts, and its potential as a cosmetic ingredient. The strain was isolated from the Mediterranean Sea star, Echinaster sepositus, and identified according to ITS molecular sequence homology as a member of Aspergillus section versicolores.To gain insight on the bioactivity underpinning the effects of TM124-S4 extract on oxidative stress, we examined a panel of a hundred genes as well as cell viability. Initially, Aspergillus puulaauensis TM124-S4 promoted cell viability.The change in gene transcripts revealed that Aspergillus puulaauensis TM124-S4 extracts exhibited skin protection properties by mediating cell proliferation (EPS8, GDF15, CASP7, VEGFA), antioxidant response (CAT, SOD1, TXN, GPX1), skin hydration (CD44, CRABP2, SERPINE) and DNA repair (PCNA, P21). The extract also modulated the expression of genes involved in skin pigmentation and aging (TYR, FOXO3).These findings indicate that Aspergillus puulaauensis TM124-S4 extract possesses significant in-vitro skin protection activity against induced oxidative stress.Furthermore, new insights are provided into the beneficial role of fungal bioactive compounds in skin related research.

A Neutrophil Proteomic Signature in Surgical Trauma Wounds

Non-healing wounds continue to be a clinical challenge for patients and medical staff. These wounds have a heterogeneous etiology, including diabetes and surgical trauma wounds. It is therefore important to decipher molecular signatures that reflect the macroscopic process of wound healing. To this end, we collected wound sponge dressings routinely used in vacuum assisted therapy after surgical trauma to generate wound-derived protein profiles via global mass spectrometry. We confidently identified 311 proteins in exudates. Among them were expected targets belonging to the immunoglobulin superfamily, complement, and skin-derived proteins, such as keratins. Next to several S100 proteins, chaperones, heat shock proteins, and immune modulators, the exudates presented a number of redox proteins as well as a discrete neutrophil proteomic signature, including for example cathepsin G, elastase, myeloperoxidase, CD66c, and lipocalin 2. We mapped over 200 post-translational modifications (PTMs; cysteine/methionine oxidation, tyrosine nitration, cysteine trioxidation) to the proteomic profile, for example, in peroxiredoxin 1. Investigating manually collected exudates, we confirmed presence of neutrophils and their products, such as microparticles and fragments containing myeloperoxidase and DNA. These data confirmed known and identified less known wound proteins and their PTMs, which may serve as resource for future studies on human wound healing.

Differential proteomics of lesional vs. non-lesional biopsies revealed non-immune mechanisms of alopecia areata

Alopecia areata (AA) is one of the common hair disorders for which treatment is frequently ineffective and associated with relapsing episodes. Better understanding of disease mechanisms and novel therapeutic targets are thus required. From 10 AA patients, quantitative proteomics using LTQ-Orbitrap-XL mass spectrometer revealed 104 down-regulated, 4 absent, 3 up-regulated and 11 newly present proteins in lesional vs. non-lesional biopsies. Among these, the decreased levels of α-tubulin, vimentin, heat shock protein 70 (HSP70), HSP90, annexin A2 and α-enolase were successfully confirmed by Western blotting. Protein-protein interactions network analysis using STRING tool revealed that the most frequent biological processes/networks of the down-regulated proteins included tissue development, cell differentiation, response to wounding and catabolic process, whereas those for the up-regulated proteins included biological process, metabolic process, cellular transport, cellular component organization and response to stimulus. Interestingly, only 5 increased/newly present proteins were associated with the regulation of immune system, which may not be the predominant pathway in AA pathogenic mechanisms as previously assumed. In summary, we report herein the first proteome dataset of AA demonstrating a number of novel pathways, which can be linked to the disease mechanisms and may lead to discovery of new therapeutic targets for AA.

Fibrinogen-Related Proteins in Tissue Repair: How a Unique Domain with a Common Structure Controls Diverse Aspects of Wound Healing

Significance: Fibrinogen-related proteins (FRePs) comprise an intriguing collection of extracellular molecules, each containing a conserved fibrinogen-like globe (FBG). This group includes the eponymous fibrinogen as well as the tenascin, angiopoietin, and ficolin families. Many of these proteins are upregulated during tissue repair and exhibit diverse roles during wound healing. Recent Advances: An increasing body of evidence highlights the specific expression of a number of FRePs following tissue injury and infection. Upon induction, each FReP uses its FBG domain to mediate quite distinct effects that contribute to different stages of tissue repair, such as driving coagulation, pathogen detection, inflammation, angiogenesis, and tissue remodeling. Critical Issues: Despite a high degree of homology among FRePs, each contains unique sequences that enable their diversification of function. Comparative analysis of the structure and function of FRePs and precise mapping of regions that interact with a variety of ligands has started to reveal the underlying molecular mechanisms by which these proteins play very different roles using their common domain. Future Directions: Fibrinogen has long been used in the clinic as a synthetic matrix serving as a scaffold or a delivery system to aid tissue repair. Novel therapeutic strategies are now emerging that harness the use of other FRePs to improve wound healing outcomes. As we learn more about the underlying mechanisms by which each FReP contributes to the repair response, specific blockade, or indeed potentiation, of their function offers real potential to enable regulation of distinct processes during pathological wound healing.