For instance, an inverse relationship was described between the chlorambucil effect and GSH levels and activity [119,120] or between GSH levels and the concentration of cyclophosphamide active metabolites, suggesting a possible decrease in their efficacy during anticancer treatments [121]
Specifically, GSTP1 results in reduced catalytic activity, while GSTT1 and GSTM1 null/null genotypes exhibit a complete absence of catalytic activity
Clinical Nutrition Open Science, 41, 100065
Skin has adapted to current levels and requires higher signaling intensity to continue progressing
Moreover, overexpression of specific GSTs can also affect chemoresistance, whereas polymorphisms that decrease GST activity are associated with a high risk of developing cancer [72]
Here's what GHK-Cu may be able to help you with: Skin firmness and texture : It could encourage firmer, smoother-looking skin Fine lines : May help with how prominent fine lines and wrinkles look