title: Structural activity relationship analysis (SAR) and in vitro testing reveal the anti-ageing potential activity of acetyl aspartic acid.
abstract: BACKGROUND
  Acetyl aspartic acid (A-A-A) was discovered through gene array analysis with corresponding connectivity mapping (Cmap), aiming for identification of new compounds with anti-ageing properties.
  
  
  OBJECTIVE
  The aim of this study was to use structural activity relationship (SAR) analysis to identify a predictive mechanism of action of A-A-A. The findings from SAR will be further characterized by in vitro activity testing. Furthermore, we aimed to investigate the role of polymerized filamentous F-actin in ageing fibroblasts and to evaluate the effect of A-A-A on this model.
  
  
  METHODS
  To predict the mode of action of A-A-A, we used the PASS computer program as a SAR model. In vitro, scratch motility tests with immortalized keratinocytes were used as a model for wound healing potential. Matrix metalloproteinase 1-3 (MMP 1-3) was analysed using multiplex protein assays (Luminex), and polymerized actin was detected by phalloidin staining in dermal fibroblasts (HDF).
  
  
  RESULTS
  SAR analysis predicted that A-A-A would possess both epidermal and dermal activities with identification of wound healing and MMP inhibition potential. Further in vitro studies confirmed the wound healing potential using keratinocyte scratch motility assays. We were also able to confirm the dermal activities predicted by inhibition of MMP (MMP 1-3) in HDF by A-A-A. In addition, we found a positive relationship between age and F-actin expression. We also discovered that stimulation of HDF with A-A-A for 72 h significantly reduced the polymerized cytoskeletal network as visualized by inhibition of F-actin expression. In fact, A-A-A leveraged the expression of F-actin in middle-aged female fibroblasts (50 years of age) to the level of young female fibroblasts (30 years of age), corresponding to a 40% reduction in F-actin expression.
  
  
  CONCLUSIONS
  Using an in silico and in vitro approach, we were able to demonstrate that A-A-A has the capacity to target different compartments of the skin through keratinocyte regeneration, MMP inhibition and relief in fibroblasts stiffness by reduction of F-actin cytoskeletal network in HDF.
authors.affiliation: Oriflame Skin Research Institute, Mäster Samuelsgatan 56, Stockholm, 11121, Sweden.
authors.forename: J M
authors.initials: JM
authors.lastname: Gillbro
authors.affiliation: Oriflame Skin Research Institute, Mäster Samuelsgatan 56, Stockholm, 11121, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Lundahl
authors.affiliation: Oriflame Skin Research Institute, Mäster Samuelsgatan 56, Stockholm, 11121, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Westman
authors.affiliation: Oriflame Skin Research Institute, Mäster Samuelsgatan 56, Stockholm, 11121, Sweden.
authors.forename: R
authors.initials: R
authors.lastname: Baral
authors.affiliation: Oriflame Skin Research Institute, Mäster Samuelsgatan 56, Stockholm, 11121, Sweden.
authors.forename: T
authors.initials: T
authors.lastname: Al-Bader
authors.affiliation: Oriflame Skin Research Institute, Mäster Samuelsgatan 56, Stockholm, 11121, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Mavon
mesh_terms: D001224:Aspartic Acid / Q000737:chemistry / Q000494:pharmacology*; D002461:Cell Line, Transformed; D006801:Humans; D066298:In Vitro Techniques; D020782:Matrix Metalloproteinases / Q000187:drug effects; D011480:Protease Inhibitors / Q000494:pharmacology; D015595:Skin Aging / Q000187:drug effects*; D013329:Structure-Activity Relationship
chemical_list: D011480:Protease Inhibitors; D001224:Aspartic Acid; D020782:Matrix Metalloproteinases
keywords: F-actin; in silico; matrix metalloproteinase; prediction of activity spectra of substances; scratch motility test