As an endogenous human tripeptide used topically for decades in skincare, GHK-Cu is generally regarded as well tolerated, with the most common issues being local irritation, redness, or contact sensitivity in susceptible individuals
Simko F, Luptak I, Matuskova J, Krajcirovicova K, Sumbalova Z, Kucharska J, Gvozdjakova A, Simko J, Babal P, Pechanova O, Bernatova I
Subsequent to secretion, active GLP-1 is rapidly cleaved and inactivated by dipeptidyl peptidase-4 (DPP4) in target tissues, resulting in a half-life of only 2 minutes (54, 55) ( Figure 2G, scheme )
Rashidy-Pour A, Pahlevani P, Vaziri A, Shaigani P, Zarepour L, Vafaei AA, et al
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