Peeling agents and irritants, unlike tretinoin, do not stimulate collagen synthesis in the photoaged hairless mouse

Abstract

Tretinoin has been shown to stimulate the synthesis of collagen in photo-aged human and hairless mouse skin. It has been suggested that this partial reversal of photodamage by tretinoin is a consequence of low-grade inflammation. The purpose of this study was to compare the effect of tretinoin with a number of irritants and peeling agents on collagen synthesis. Hairless mice were irradiated thrice weekly for 10 weeks with UVB. In the 10-week postirradiation period, the mice were treated topically five times per week with tretinoin (0.05%), glycolic acid (10%), benzalkonium chloride (1.0%), sodium lauryl sulfate (5%), croton oil (5%) and the water - propylene glycol vehicle. Microscopic measurements showed that the tretinoin-induced zone of new collagen was twice the depth of that induced by irritants or vehicle. The salt-soluble collagen content was determined by HPLC analysis of hydroxyproline levels. Type III procollagen was quantified by radioimmunoassay. Tretinoin-treated skin had increased amounts of collagen and type III procollagen whereas irritant- and peeling agent-treated skins were similar to vehicle-treated controls. Immunofluorescence studies were confirmatory. These results demonstrate that these agents, unlike tretinoin, do not have the capacity to enhance collagen synthesis. Therefore, it is likely that the effect of tretinoin does not depend upon irritation.

Comparison of Epidermal Morphologic Response to Commercial Antiwrinkle Agents in the Hairless Mouse

“…In a comparative way, the present observations show that GA and RA used as topical agents induced stimulation of the epidermis, but whether they stimulate collagen synthesis in an identical manner remains to be explored. In the irradiated photoaged hm, Kligman and colleagues 30 reported greater amounts of collagen formation with RA treatment, whereas skin treated with peeling agents such as 10% GA had values similar to vehicle‐treated controls. The present findings with GA are also different from that of Kim and colleagues, 31 who applied 10% GA for 14 days in normal hm, resulting in less epidermal thickness but greater collagen synthesis and fibroblast proliferation with greater dermal thickness.…”

Safety Evaluation and Anti-wrinkle Effects of Retinoids on Skin

“…Solutions of vehicle (DAE 433) , t-ROL (0.1%) , or t-RA (0.1%) were applied to the dorsal trunk with occlusion for 6 days. Immunohistological analysis of type I pN collagen was performed according to the methods described previously (Kligman et al , 1996) . Type I pN collagen was detected with mice monoclonal IgG1 antibody (Santa Cruz Biotechnology, CA, USA) raised against the aminoprepeptide region of human type I procollagen.…”

The use of hydroxy acids on the skin: characteristics of C8‐lipohydroxy acid

“…The use of chemical peeling agents, laser resurfacing, or topical retinoids can reverse some of the signs of photoaging. Although the gold standard for treatment is tretinoin, 30,31 the efficacy of the hydroxy acids has been repeatedly reported 14,32–35 …”