Association of vitamin B-6 status with inflammation, oxidative stress, and chronic inflammatory conditions: the Boston Puerto Rican Health Study.
BACKGROUND
Low vitamin B-6 status has been linked to an increased risk of cardiovascular diseases. The cardioprotective effects of vitamin B-6 independent of homocysteine suggest that additional mechanisms may be involved.


OBJECTIVE
Our objective was to examine the cross-sectional association of vitamin B-6 status with markers of inflammation and oxidative stress.


METHODS
We measured plasma pyridoxal-5'-phosphate (PLP), C-reactive protein (CRP), and an oxidative DNA damage marker, urinary 8-hydroxydeoxyguanosine (8-OHdG), in Puerto Rican adults who were living in Massachusetts (n = 1205, aged 45-75 y).


RESULTS
There was a strong dose-response relation of plasma PLP concentration with plasma CRP. Increasing quartiles of PLP were significantly associated with lower CRP concentrations (geometric means: 4.7, 3.6, 3.1, and 2.5 mg/L; P for trend < 0.0001) and with lower urinary 8-OHdG concentrations (geometric means: 124, 124, 117, and 108 ng/mg creatinine; P for trend: 0.025) after multivariate adjustment. These negative associations persisted after plasma homocysteine was controlled for. Plasma PLP concentrations were significantly correlated with plasma fasting glucose (r = -0.1, P = 0.0006), glycated hemoglobin (r = -0.08, P = 0.006), and homeostasis model assessment of beta cell function (r = 0.082, P = 0.005). Metabolic syndrome, obesity, and diabetes were also significantly associated with low plasma PLP concentrations (P = 0.011, 0.0007, and 0.004, respectively).


CONCLUSIONS
Low vitamin B-6 concentrations are associated with inflammation, higher oxidative stress, and metabolic conditions in older Puerto Rican adults. Our data suggest that vitamin B-6 may influence cardiovascular disease risk through mechanisms other than homocysteine and support the notion that nutritional status may influence the health disparities present in this population.
Shen
Jian
J
Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111-1524, USA.
Lai
Chao-Qiang
CQ
Mattei
Josiemer
J
Ordovas
Jose M
JM
Tucker
Katherine L
KL
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000368:Aged; D001900:Boston; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000097:blood / Q000378:metabolism* / Q000517:prevention & control / Q000652:urine; D003430:Cross-Sectional Studies; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000652:urine; D005260:Female; D006630:Hispanic or Latino; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D008297:Male; D024821:Metabolic Syndrome / Q000378:metabolism*; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D011732:Pyridoxal Phosphate / Q000097:blood; D018709:Statistics, Nonparametric; D025101:Vitamin B 6 / Q000378:metabolism*
D011732:Pyridoxal Phosphate; D025101:Vitamin B 6; D000080242:8-Hydroxy-2'-Deoxyguanosine; D002097:C-Reactive Protein; D003849:Deoxyguanosine