Safety fears have been highlighted by significant differences in the way children’s bodies deal with medications when compared with adults. According to recent research, proteins crucial to the activity of medicines behave quite differently in kids. The proteins are enzymes acting as biochemical catalysts. Depending on how they work, they can make a medication successful, useless, or toxic. The new study discovered that some enzymes known to share regulatory mechanisms in adults emerge to employ different ones in growing kids.
Researchers also discovered a period of higher-than-normal variability for some enzymes within the first 3 to 6 months after birth, which suggests that activity of these proteins can differ considerably among individual children at this sensitive time.
Professor Ronald Hines, from the Medical College of Wisconsin in the United States, said: “The dramatic changes observed in enzyme expression must be considered when examining issues of drug effectiveness and safety during early life stages. Additional research is necessary to understand how these significant changes are regulated, and the molecular basis for differences among individuals, to better predict drug and toxicant responses in children.”
The findings were demonstrated at the annual meeting of the American Association for the Advancement of Science in St Louis, Missouri. A key discovery related to the oxidative enzyme CYP3A4. Kids of one or two had only 20% to 50% of adult activity levels of this protein.
In contrast, almost 50% of kids had nearly adult levels of another important enzyme, CYP2C9, at or near birth. Another enzyme called SULT2A1 was low or absent in the foetus during the first 3 months of pregnancy, highly variable in the first 4 months of life, and rose gradually to adult values by age one.
