Abstract
Pyridoxine, a B6 vitamin, is a co-factor in a variety of enzymatic reactions involved in intermediary metabolism. The effects of pyridoxine deficiency and supplementation on hematological profiles, lymphocyte function, and hepatic CYP1A1 and CYP2E1 were investigated in B6C3F1 mice fed a diet containing either 0 (i.e., pyridoxine-deficient diet, [PD]); or 7 mg pyridoxine-HCl/kg (i.e., control diet, [CD]) for 8 or 13 weeks followed by administration of 500 μg pyridoxine-HCl (IP) daily for either 2 (PD-S2 and CD-S2) or 3 (PD-S3 and CD-S3) consecutive days. Results demonstrated that erythrocyte aspartate aminotransferase activity coefficient (EAST-AC) values, which reflect host pyridoxine status, were significantly higher in PD mice than in CD mice, and dropped to control levels after supplementation. PD mice had significantly reduced weight gains, mean corpuscular volume (MCV), hemoglobin (HGB), and hematocrit (HCT) levels compared to CD mice after 8 and 13 weeks on the prescribed diet. In addition, PD mice had significantly lower circulating levels of total white blood cells, but higher red blood cell numbers after 8 weeks (compared to CD mice). Pyridoxine supplementation for 3 days restored HGB levels in PD mice to that of the unsupplemented CD controls; HCT, MCV and MCH levels were also increased in PD-S3 mice compared to their unsupplemented PD counterparts, but failed to reach comparable levels to those seen in mice fed a control diet. The pyridoxine-deficient diet also resulted in decreased mitogen stimulated T-lymphocyte proliferation after a 13-week feeding regimen and increased hepatic CYP1A1 activity that was reversed by pyridoxine supplementation. These studies demonstrate in a murine model that pyridoxine deficiency can cause multiple alterations that, in many cases, can be reversed by supplementation.
Acknowledgments
The research described herein was supported by the Chulabhorn Research Institute and a grant from the Center of Excellence on Environmental Health, Toxicology and Management of Toxic Chemicals (ETM) under Science & Technology Postgraduate Education and Research Development Office (PERDO) of Ministry of Education.
Declaration of interest: The authors declare that there are no conflicts of interest in the design and conducting of this study. The authors alone are responsible for the content and writing of the paper.