Relation of Redox and Structural Alterations of Rat Skin in the Function of Chronological Aging

Figure 4

Time-course changes in the levels of HNE-modified proteins in the skin of 3-day-, 15-day-, 1-month-, 3-month-, 6-month-, and 21-month-old rats. The immunohistochemical method was used to detect skin tissue proteins modified by 4-hydroxynonenal (HNE) for subsequent quantitative image analysis (b). The brown staining testifies to the specific reaction. Strong HNE immunopositivity of the basal lamina, along with its partial discontinuation/disruption (black arrows), was observed in 21-month-old rat skin (c, left inset, arrows). Dermoepidermal junctions and the basal cell deep projections into the dermis were also disturbed (c, middle and right, arrows). (a) Representative slides of HNE immunohistochemistry are shown at ×40 (corner inset) and ×100 magnification, orig. The quantitative evaluation of HNE antibody staining intensity in skin sections (b) was analyzed as described in Figure 3. (c) Magnification: semifine section, toluidine blue staining: ×100, orig. Insets: left—HNE immunohistochemistry: ×100 orig.; right—transmission electron microscopy, bar: 2 μm. The relative mean intensity was determined from 6 images for each aging group (). Data were presented as . In respect to 3-month-old rats; ; .

(a)

(b)

(c)