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
Methodology:
- -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
Results:
- -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)
Methodology:
- -stimulation of cells with tobacco extracts and 30J/cm2 UVA
- -collagen
- -MMP and TIMPS (protéases inhibitors)
Results
- 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…)
Study
Methodology:
- -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
