Polyamine Oxidase and Diamine Oxidase Activities in Human Milk during the First Month of Lactation|
Bjelakovic, Ljiljana; Kocic, Gordana; Bjelakovic, Bojko; Najman, Stevo; Stojanović, Dusica; Jonovic, Marina & Pop-Trajkovic, Zoran
Objective: Human milk (HM) is the ideal food for all newborns and infants. Apart from various bioactive
compounds, including cytokines, antibodies, hormones, vitamines, it also contains polyamines, such as
spermine (Sp), spermidine (Spd) and putrescine (Put).
Aim: The present study investigated polyamine metabolism in colostrum and mature human milk by
measuring the polyamine oxidase (PAO) and diamine oxidase (DAO) enzyme activities, which are necessary
for polyamine catabolism, as well as by determining the malondialdehyde (MDA) levels, the final product of
Methods: The PAO, DAO activity and MDA levels were quantified in colostrum (1st and 2nd day) as well as in
mature human milk, 30th day of lactation.
Findings: We found the steady increase of PAO activity and steady decrease of DAO activity and MDA levels
during first month of lactation.
Conclusion: Since the products of PAO activity such as, amino aldehydes and hydrogen peroxide (H2O2) might
have potential antimicrobial effects, promoting the oxidative stress, it is likely that human milk PAO
throughout the lactation period, contributes to the protective effects of human milk.
Human Colostrum; Mature Milk; Polyamine Oxidase; Diamine Oxidase; Malondialdehyde