Related Experiment Videos
Antioxidative vitamins in prematurely and maturely born infants
1Johann-Wolfgang-Goethe-Universität, Frankfurt, Germany.
Insights
Neonatal antioxidant vitamins E, C, A, and B2 are crucial for combating oxidative stress from hyperoxia. Vitamin E protects lipids, while C and B2 support water-soluble defenses, aiding development and preventing complications.
Area of Science:
- Biochemistry
- Neonatal Physiology
- Nutritional Science
Background:
- Newborns transition from a hypoxic to a hyperoxic environment postnatally, increasing risks of reactive oxygen species (ROS) formation, particularly with artificial ventilation.
- Non-enzymatic antioxidant systems, including vitamins E, C, A, and B2 (riboflavin), play a critical role in protecting against oxidative damage in neonates.
Purpose of the Study:
- To review the importance and roles of key antioxidant vitamins (E, C, A, B2) in neonatal physiology.
- To highlight the implications of vitamin deficiencies and their impact on neonatal health outcomes, especially concerning oxygen exposure and development.
Main Methods:
- Literature review of the physiological roles and metabolism of antioxidant vitamins in the neonatal period.
- Analysis of the impact of vitamin status on conditions like retinopathy of prematurity, intraventricular hemorrhage, and lung development.
Main Results:
- Vitamin E is a primary lipid-soluble antioxidant, crucial for protecting cell membranes and can prevent retinopathy and intraventricular hemorrhage.
- Vitamin C and glutathione are key water-soluble antioxidants; vitamin C status is best assessed in leukocytes.
- Vitamin B2 (riboflavin) acts indirectly by maintaining reduced glutathione levels and is susceptible to photodegradation during phototherapy.
- Vitamin A is vital for lung development, regulating surfactant protein expression, with neonatal levels often lower than maternal levels.
Conclusions:
- Antioxidant vitamins E, C, A, and B2 are essential for neonatal adaptation to the hyperoxic postnatal environment and for preventing oxidative stress-related morbidities.
- Maintaining adequate vitamin status is critical for optimal neonatal development, particularly lung maturation and protection against common neonatal complications.
Abstract:
Postnatally a rapid change occurs from a relatively hypoxic to a relatively hyperoxic environment, especially during artificial ventilation with all risks of ROS-formation. Among the non enzymatic antioxidative strategies the vitamins E, C, A and B2 are of major importance. Vitamin E is considered the most important radical scavenging vitamin of the lipid soluble compartment. Hereby vitamin E itself is converted into a radical which is handed over to vitamin C and glutathione into the water soluble compartment. The vitamin E content of the fetus increases with the fetal fat mass mainly during the last trimester of pregnancy. Placenta is only slightly permeable to lipid soluble vitamins. Vitamin E deficiency may rapidly develop typically at about 6-8 weeks of age. Vitamin E is able to prolong significantly the onset of retinopathic changes during oxygen therapy and may prevent intraventricular hemorrhage. Vitamin C is together with glutathione a major representative of the non enzymatic antioxidative system in the water soluble compartment. The best determinant of the vitamin C status is its concentration in leukocytes. Vitamin C reduces iron to the divalent state which supports the hydroxyl radical formation (Haber-Weiss reaction). This should be considered mainly in cases of intraventricular hemorrhage. Vitamin B2 acts mainly as cofactor of glutathione reductase which keeps glutathione in the reduced state. It can therefore be considered an indirect antioxidative vitamin. Vitamin B2 is destroyed by light. Phototherapy has been recognized as a cause of riboflavin deficiency. Vitamin A comprises all retinols with properties like trans-retinol. Retinol storage in the fetal liver increases during late pregnancy. In both, premature and mature newborns, the serum concentrations amount to only about 50% of those of their mothers. Vitamin A has a paramount importance for fetal lung development, because the individual surfactant proteins are selectively regulated by retinoic acid.