Age - Related Changes of Glycosaminoglycan in Senescence - Accelerated Mouse ( SAM ) Skin

Cha, Seung Hoon; Kim, Seung Hoon; Won, Young Ho; Kim, Young Kon; Kim, Young Pio; Chun, Inn Ki

Abstract

BACKGROUND: The various manifestations of intrinsic cutaneous aging may reflect the age-related changes of dermal ground aubstances, the important components of the dermis.
OBJECTIVE
This study was undertaken to observe whether there is any age-relsted change, quantitatively and qualitatively, in dermal glycosaminoglycan(GAG)
METHODS
The Senescence-A.ccelerated-Mice(SAM) strain "Prone" to develop senescence(P/8), aged 4 days(P-Y a group, n=5) and 4 months old (P-0 group, n=5) were used, with SAM strain Resistance to senescence (R/1), aged 4 montha old (R-0 group, n=5). The whole skin of SAM was incubated in 0.1 sodium phosphate buffer(NaPB), 2M guanidine-HC1, and 4M guanidine-HCl, sequencially, for the extractiop of GAG. The amount of GAG was measured by using alcian blue and by methylene blue metachrometic assay. Uronic acid(UA) was estimate l employing carbazole reaction. Extracted skin protein profiles were analyed by SDS-PAGE.
RESULTS
1. The total contents of GAG per wet weight of skin, as measured uairq, alcian blue, was highter in R-0 group than R-Y and P-Y group, which is statistically significant. 2. The methylene blue metaehromatic assay yielded highter absorbance values in 2M guanidine-HCl extract than NaPB ext:racts. 3. The total contents of UA decreased with aging in R strains, buttriking increase was noted in the P strain. 4. On SDS-PAGE, the protein profiles of NaPB extracts showed similarity to serum protein. 125 kDa protein band was noted only in guanidine-HCl extracts. 37.40kDa protein bands were appeared in 2M, 4M guanicline-HCl extract of R-0 group. But. there was no significant difference in both strains.
CONCLUSION
These findings suggest that macromolecules, such as GAG, is one of the target molecules of the cutaneous eging process, and these change muy be related to the age-related changes of dermal water content.