Abnormal vitamin B6 metabolism is commonly present in patients with chronic inflammation, such as rheumatoid arthritis (RA). Although indirect evidence suggests that acute and high doses of glucocorticoids may affect vitamin B6 homeostasis, it is not known whether long-term prednisolone affects vitamin B6 metabolism. Chang et al. systematically investigated the impact of long-term physiological doses of prednisolone on vitamin B6 profiles in two independent animal models. Long-term prednisolone increased hepatic vitamin B6 concentrations through induction of synthetic enzymes and suppression of catabolic enzymes involved in vitamin B6 metabolism. The elevated levels of plasma vitamin B6 vitamers did not result in accelerated excretion of vitamin B6. These results demonstrate that at clinically relevant doses, prednisolone does not alter vitamin B6 ingestion or excretion but may accelerate the interconversions and mobilization of B6 vitamers in a tissue-specific manner. Considering the high prevalence of long-term vitamin B6 depletion in RA, it is suggested that the action of prednisolone in increasing circulating vitamin B6 be taken into account when considering the potential advantages and disadvantages of using glucocorticoids in the treatment of inflammatory disorders.
See article at J Pharmacol Exp Ther 2011, 337:102–109.
- Copyright © 2011 by The American Society for Pharmacology and Experimental Therapeutics