Two types of aging:

  • -intrinsic aging
  • -extrinsic aging: ultraviolet and tobacco smoking


Odds ratios for wrinkles in patients with risk factors versus no risk factor individuals

  • -sun exposure: 2.65
  • -smoking: 35 PA: 5.8
  • -age more than 80 years old: 7.5


Daniells score to measure wrinkles


Fact: 4 package years = +1 year’s in the advancing of wrinkles formation:



Study on extrinsic aging and formation of wrinkles in 3 parts to chow clinical and molecular changes showing involvement of the Aryl Hydrocarbon Pathway (AhR)



Part 1

The presenter did a study in Japanese and German women

Conclusion: Japanese develop pigment spots and german develop wrinkles




  • -53 German women and 18 Japanese women living in the region of Düsseldorf, Germany  aged 30 to70 years of age
  • -48 Japanese women living in the region of Nagoya, Japan aged 30 to 70


  • -questionnaire: smoking, sunbed, living next to a road
  • -skin ageing score
  • -blood tests




  • -Japanese women have more pigment earlier and German women have more wrinkles at an earlier age
  • -Smoking increases spots back of hands in German women and wrinkles appear on the upper lip in Japanese women



Part 2

Objective: to measure molecular changes (in fibroblasts)




  • -stimulation of cells with tobacco extracts and 30J/cm2 UVA
  • -collagen
  • -MMP and TIMPS (protéases inhibitors)




  • increase MMP
  • collagen synthesis decreased
  • tropoelastin
  • proteoglycan accumulation
  • reduced proteinases inhibitors)



Part 3

Tobacco has 3800 constituents and include polycyclic aromatic hydrocarbons (PAH)

AhR (Aryl hydrocarbon receptor):

  • -located in the cytosol
  • -lipophilic
  • -links to UVB and xenobiotics (also known as dioxin receptor)
  • -once linked to particles, translocated to the nucleus where it induces its effect (expression of CYp1A1…)





  • -done on HaCaT, keratinocytes and fibroblasts with PCR expression (Polymerase Chain Reaction).



Results show that Hexane soluble extracts (Lipophilic) (and to PBS (Phosphate Buffer Saline) water soluble soluble):

  • -increases MMP1:
  • -reduces proteoglycans
  • -reduces procollagen (I and III)
  • -induces CYP1a1 (Cytochrome P1a1) and CyP1B1 expression (PCR)
  • -AHR is proven to be the obliged pathway because this response is abolished in AhR knockout mice
  • -Smoke extracts also induce 7-ethoxyresorufin-o-deethylaser activity (which is also abolished in AhR knockouts)
  • -Flavanoids 3-methoxy-4-nitroflavone and naphtoflavone blocks the induction of CYP1B1 and MMP-1.



Conclusion: the AhR pathway may be pathogenetically involved in extrinsic skin aging.



Morita A, Aging and Photoaging – 22nd World Congress of Dermatology (WCD) – Seoul, South Korea