Role Of The Microfibrills of Fibrillin In Aging (Ageing) And Photoaging (Photoageing) (Sun-induced Ageing)

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:

1. 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)
2. With molecular combing, tensile strength to determine distance and elastic potential

• Results:

1. Up to 30 years old 0.9% of fibrillin microfibrills are separated by more than 100nm
2. Over 70 years old this goes up to 18.2 %
3. on immunohistochemistry buttocks vs photoexposed skin in 7o year old individuals show loss of candelabra structure of fibrillinand 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

Source of information: here