Phosphorylase kinase (PhK) is a unique
enzyme in which the spatial arrangements of the specificity determinants can be manipulated to allow the
enzyme to recognize substrates of different specificities. In this way, PhK is capable of transferring high energy
phosphate bonds from
ATP to
serine/
threonine and
tyrosine moieties in
serine/threonine kinases and
tyrosine kinases, thus playing a key role in the activation of multiple signaling pathways.
Phosphorylase kinase is released within five minutes following injury and is responsible for activating inflammatory pathways in injury-activated
scarring following
burns. In photo-damaged skin, PhK plays an important role in promoting photocarcinogenesis through activation of
NF-kB-dependent signaling pathways with inhibition of apoptosis of photo-damaged cells, thus promoting the survival of precancerous cells and allowing for subsequent
tumor transformation.
Curcumin, the active ingredient in the spice, turmeric, is a selective and non-competitive PhK inhibitor. By inhibition of PhK,
curcumin targets multiple PhK-dependent pathways, with salutary effects on a number of
skin diseases induced by injury. In this paper, we show that
curcumin gel produces rapid healing of
burns, with little or no residual
scarring.
Curcumin gel is also beneficial in the repair of photo-damaged skin, including pigmentary changes, solar elastosis, thinning of the skin with
telangiectasia (actinic poikiloderma), and premalignant lesions such as
actinic keratoses,
dysplastic nevi, and advanced solar
lentigines, but the repair process takes many months.