Presentation of fibrillin
- -is an extracellular protein
- -is responsible as scafolding for deposition elastic fibres
- -exists as fibrillin f1 and 2
- -encoded by FBN1 and 2
- -encoding Marfan syndrome
Functions of fibrillin:
- -strengthens elastic fibres and enables transmission of forces between the epidermis and dermis
- -What is elastic tissue = elastin + microfibrills fibers
Elastic tissue differences between age groups 18-30 and over 70
Methodology:
- -with atomic force microscopy to determine distance between microfibrills (of fibrillin) (periodicty 56nm=no strain, more than 100=strained and unable to strap back= loss of elasticity)
- -With molecular combing, tensile strength to determine distance and elastic potential
Results:
- -Up to 30 years old 0.9% of fibrillin microfibrills are separated by more than 100nm
- -Over 70 years old this goes up to 18.2 %
- -on immunohistochemistry buttocks vs photoexposed skin in 7o year old individuals show loss of candelabra structure of fibrillin and also a reduction of fibrillin staining in the papillary dermis
Mechanisms of age-related damage:
- -upgrading MMPs (matrix metalloproteinase)
- -cleavage of proMMP
- -upregulation MMP 2 and 9
- -degradation of microfibrills by UV
By using atomic force and electron microscopy microfibrills of fibrillin respond to UVB by:
- -increasing diameter
- -becoming more tangled (increased flexion angle)
- -reducing their mass with increasing UV dosage (mass mapping)
UVR exposed fibrillin fibres are therefore:
- -shorter
- -weaker
- -have a reduced mass
Treatment
- -Over 4 years of nightly application, retinoic acid 0,1% reduces photoaging by reconstituting the fibrillin quantity and candelabra disposition.
Griffiths C, Aging and Photoaging – 22nd World Congress of Dermatology (WCD) – Seoul, South Korea
