Epidermal transglutaminase

F. Epidermal Transglutaminase Activity and Cornified Envelope Formation... 

Feingold and his coworkers demonstrated an important role of nuclear hormone receptor on epidermal differentiation and stratum corneum barrier formation. Activation ofPPARa Peroxisome proliferator-activated receptor a by farnesol also stimulated the differentiation of epidermal keratinocytes.42 Cornified envelope formation, involcrin, and transglutaminase protein, and mRNA levels were also increased by the activation of PPARo . Interestingly, the inflammatory response was also inhibited by the treatment.43 They also showed that topical application of PPARo activators accelerated the barrier recovery after tape stripping or acetone treatment and prevented the epidermal hyperplasia induced by repeated barrier disruption.42 Regulation of the nuclear hormone receptor would open a new possibility for improvement of the cutaneous barrier. 

Transglutaminase catalyzes cross-linking between peptide chains in fibrin clots, the cornihed envelope of epidermal cells, and the vaginal plug from seminal plasma in rodents. Glutaminyl residues serve as acyl donors to peptide-bound lysine. This assay makes use of a small synthetic peptide, benzyloxycarbonyl-L-Gln-Gly, and fluorescent amine monodansylcadaverine as substrates. 

L., Piredda, L. and Fesus, L. (1991) Tissue transglutaminase is specifically expressed in neonatal rat liver cells undergoing apoptosis upon epidermal growth factor-stimulation. Cell Tissue Res. 263 227-235. 

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