MG-induced glycation for pentosidine formation in the epidermis (a) or reticular dermis (b). * p < 0.05, ** p < 0.01. MG, methylglyoxal; CML, carboxymethyl-lysine; FC-CARN, facial cream containing carnosine; AQ-CARN, carnosine in aqueous solution; ns, non-significant.