Urea for moisturizing causes carbamylation?

[Discohouse]

Dr. Todorov, I read a few articles, one of which I will post here, if you can help me analyze, but I can't figure out whether topically applying urea onto the skin can cause urea-derived isocyanic acid, forming carbamylation, which then leads to CDPs (carbamylation-derived products). This leads to protein deterioration, a process beyond the effects of glycation. Is this true?


The studies seem to talk about urea in the body, but what about topical urea, or urea derivatives, such as hydroxyethyl urea, and others?

I'm not sure whether there are any articles on whether topically applied urea can cause the same reaction or not, and whether that is a concern similar to glycation.

If you read the article and search in your browser (windows: control+f, then input urea), to see how urea causes carbamylation.


"Protein carbamylation is a hallmark of aging"
Proceedings of the National Academy of Sciences of the United States of America (PNAS)
pnas.org/content/113/5/1191

If you wish, I can post parts of the article if you do not wish to read the above link.


Here is only one passage from the published article:

Again, I understand this is an article about its process within the human body, but I would love to know your input on what factors could cause this process in our skin as well.
Thank you in advance, Dr. Todorov.




"The justified interest expressed for glycoxidation may, however, have distracted attention from other important pathophysiological mechanisms of aging. Indeed, it has been shown that another NEPTM, carbamylation, participated in protein molecular aging. This reaction corresponds to the binding of isocyanic acid to free amino groups and preferentially occurs on the ε-NH2 of lysine residues generating homocitrulline (HCit) (Fig. 1), the most characteristic carbamylation-derived product (CDP) (14, 15) that can be specifically quantified (16). Isocyanic acid is mainly formed by the spontaneous dissociation of urea into cyanate and ammonia (15) but may also derive from thiocyanate through myeloperoxidase action (17, 18). Isocyanic acid generated from biomass burning, biofuel use, or tobacco use has been described as a minor environmental source (19)."