A postabsorption effect of L-ascorbic acid on copper metabolism in chicks

Area of Science:

• Biochemistry
• Nutritional Science
• Animal Physiology

Background:

• Copper is an essential trace element vital for various physiological processes.
• Lysyl oxidase is a copper-dependent enzyme crucial for connective tissue formation.
• Vitamin C (L-ascorbic acid) is an antioxidant with potential roles in mineral metabolism.

Purpose of the Study:

• To investigate the influence of L-ascorbic acid on copper metabolism and copper bioavailability.
• To assess the effect of L-ascorbic acid timing on copper-induced lysyl oxidase activation in copper-deficient chicks.

Main Methods:

• Copper metabolism was studied in copper-deficient chicks.
• L-ascorbic acid was administered intraperitoneally at different time points relative to copper sulfate (CuSO4) administration.
• Lysyl oxidase activity and ceruloplasmin levels were measured as indicators of copper status.

Main Results:

• Administering L-ascorbic acid before or with CuSO4 impaired copper's ability to restore lysyl oxidase activity.
• Administering L-ascorbic acid 75 minutes after CuSO4 significantly increased copper-induced lysyl oxidase activation.
• L-ascorbic acid augmented copper-induced increases in ceruloplasmin and lysyl oxidase in both deficient and adequate copper-fed chicks.

Conclusions:

• The timing of L-ascorbic acid administration critically influences its effect on copper metabolism and bioavailability.
• Post-absorption L-ascorbic acid enhances copper utilization for enzyme activation.
• Findings suggest stereospecific, post-absorptive roles for L-ascorbic acid in copper metabolism.