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Low circulating pyridoxal 5'-phosphate (PLP) concentrations have been linked to inflammatory markers and the occurrence of inflammatory diseases. However, the implications of these findings are unclear. The measurement of PLP and C-reactive protein (CRP) in blood samples collected from participants in the 2003-2004 NHANES afforded us the opportunity to investigate this relationship in the general U.S. population. Dietary and laboratory data were available for 3864 of 5041 interviewed adults, 2686 of whom were eligible (i.e. provided reliable dietary data and were not diabetic, pregnant, lactating, or taking hormones or steroidal antiinflammatory drugs). Vitamin B-6 intake was assessed using 2 24-h diet recalls and supplement use data. After multivariate adjustment for demographics, smoking, BMI, alcohol use, antioxidant vitamin status, intakes of protein and energy, and serum concentrations of creatinine and albumin, high vitamin B-6 intake was associated with protection against serum CRP concentrations >10 mg/L compared with [less than or equal to] 3 mg/L. However, plasma PLP [greater than or equal to] 20 nmol/L compared with 10 mg/L (P < 0.001). In conclusion, higher vitamin B-6 intakes were linked to protection against inflammation and the vitamin B-6 intake associated with maximum protection against vitamin B-6 inadequacy was increased in the presence compared to absence of inflammation. J. Nutr. 140: 103-110, 2010. doi: 10.3945/jn.109.114397.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jada.2009.05.011 Byline: Mary E. Keith, Natalie A. Walsh, Pauline B. Darling, Stacy A. Hanninen, Subarna Thirugnanam, Howard Leong-Poi, Aiala Barr, Michael J. Sole Abstract: The impact of heart failure and its treatment on specific nutrient requirements is unknown. Furthermore, depletion of water-soluble B vitamins that play key roles in the production of cellular energy in patients with heart failure can contribute to depletion of energy reserves observed in the failing heart. A cross-sectional study recently reported that approximately one third of hospitalized patients with heart failure had tissue levels suggestive of thiamin deficiency (vitamin B-1). Riboflavin (vitamin B-2) and pyridoxine (vitamin B-6) are similar to thiamin in that they are water-soluble, subject to renal excretion, have limited tissue storage, and are dependent on intake. Therefore, it was hypothesized that the status of these B vitamins may also be adversely affected by heart failure. As a result, the prevalence of patients at risk of vitamin B-2 (erythrocyte glutathione reductase activity coefficient [greater than or equal to]1.2) and B-6 deficiency (plasma B-6 [less than or equal to]20 nmol/L) was determined in a cross-section of 100 patients hospitalized with heart failure between April 2001 and June 2002 as well as in a group of volunteers without heart failure. Twenty-seven percent of patients with heart failure had biochemical evidence of vitamin B-2 deficiency, while 38% had evidence of B-6 deficiency. These prevalence rates were significantly higher than those observed in the volunteers without heart failure (2% and 19%, respectively; P[less than or equal to]0.02). Use of common B-vitamin-containing supplements by patients with heart failure did not significantly reduce deficiency rates in comparison with those who did not use supplements (B-2 P=0.38 or B-6 P=0.18)). Finally, while 80% of patients with heart failure took diuretics, neither the dose nor the duration of furosemide use was related to the presence of either B-2 or B-6 deficiency. Given the physiologic importance of these vitamins, further investigations aimed at determining the effect of heart failure on specific nutrient requirements as well as the safety and efficacy of B-vitamin supplementation are warranted. Article History: Accepted 26 January 2009

The catalytic power of enzymes containing coenzyme [B.sub.12] cofactor has been, in some respects, the 'last bastion' for the strain hypothesis. The present work explores the origin of this effect by using simulation methods that overcome the sampling difficulties of previous energy minimization studies. It is found that the major part of the catalytic effect is due to the electrostatic interaction between the ribose and the protein, and that the strain contribution is very small. Remarkably, enzymes can use electrostatic effects even in a radical process, when the charge distribution of the reacting fragments does not change significantly during the reaction. Electrostatic catalysis can, in such cases, be obtained by attaching a polar group to the leaving fragment and designing an active site that interacts more strongly with this group in the product state than in the reactant state. The finding that evolution had to use this trick provides further evidence to the observation that it is extremely hard to catalyze enzymatic reactions by nonelectrostatic factors. The trick used by [B.sub.12] enzymes may, in fact, be a very powerful new strategy in enzyme design. simulation of enzymatic reactions | strain effect | transition state stabilization

The 5,10-methylenetetrahydrofolate reductase (MTHER) 677-->T polymorphin and B vitamins are studied as modulators of one-carbon metabolism in 10,601 adults from the Norwegian Colorectal Cancer Prevention cohort using plasma total homocysteine as the main outcome measure. The study provides comprehensive data on the MTHER-B vitamin network, which has major effects on the transfer of one-carbon units.

Ten sets of 5 littermate pigs from each of 2 genetic strains were utilized to determine the impact of the dietary concentration of 5 B vitamins (riboflavin, niacin, pantothenic acid, cobalamin, and folacin) on growth from 9 to 28 kg of BW in pigs with high or moderate capacity for lean growth. All pigs (penned individually) were reared via a segregated, early weaning scheme, so that the lean growth potential of each strain could be expressed. The basal diet provided the 5 test vitamins at concentrations of total and estimated bioavailability equivalent to a minimum of 100 and 70%, respectively, of their estimated requirements (NRC, 1998) for 5- to 10-kg pigs. At a BW of 9 [+ or -] 0.9 kg, pigs within each litter were allotted to the basal diet supplemented with sources of the 5 test vitamins equivalent to an additional 0,100,200, 300, or 400% (bioavailable) of the NRC requirements. Pigs from the high lean strain consumed less feed (P < 0.05) and gained BW faster (P < 0.02) and more efficiently (P < 0.01) than pigs of the moderate lean strain. In both lean strains, the rate and efficiency of growth were improved (P < 0.01) as dietary B vitamin concentrations were increased. However, the dietary B vitamin concentrations needed to optimize G:F were greater (P < 0.03) in the high (>470% of NRC, 1998) vs. moderate (270%) lean strain. Based on these data, the dietary needs for 1 or more of the 5 B vitamins are greater than current NRC (1998) estimates, particularly in pigs expressing a high rate of lean tissue growth. The greater need for these vitamins is not associated with greater dietary energy intake or body energy accretion rate but is potentially due to shifts in the predominant metabolic pathways. Key words: B vitamin, lean growth strain, pig

Cysteine synthesis from homocysteine is catalyzed by two pyridoxal 5'-phosphate (PLP)-dependent enzymes. This suggests that vitamin B-6 status might affect cysteine and glutathione homeostasis, but it is unclear whether this occurs in humans. We assessed the effects of vitamin B-6 status on static and kinetic parameters of cysteine and glutathione metabolism in healthy female (n = 5) and male (n = 4) volunteers (20-30 y) before and after 4 wk of dietary vitamin B-6 restriction ( KEY WORDS: * cysteine * glutathione * human * transsulfuration * vitamin B-6

The incorporation pattern of (super 13)C-labeled samples of D-glucose within pyridoxamine dihydrochloride differed from that which was previously found within pyridoxine, isolated from Escherichia coli. Hence the biogenetic origin of the carbon skeleton of vitamin B(sub 6) in yeast differs from its origin in E. coli.

Research has been conducted on the (super)13 C-labeled vitamin B (sub)12. The results of the nuclear magnetic resonance spectrum analysis of this vitamin are presented.

Research has been conducted on the carbonyl-alkyne-exchange reactions. The use of [1,4]oxazin-2-ones as cyclic heterodienes precursors for vitamin B (sub)6 analogues synthesis is discussed.

Results of a study to establish the efficacy of Vitamin B supplementation in slowing cognitive decline in individuals with Alzheimer's disease revealed no benefits of Vitamin B. There is need for further research to try and establish some benefit of Vitamin B.

Byline: F. A. Bichkaeva (1), A. V. Tkachev (1), E. R. Boiko (2), I. V. Kulakova (1), T. V. Tret'yakova (1) Author Affiliation: (1) Ural Division, Russian Academy of Sciences, Institute of Environmental Physiology, Arkhangel'sk, Russia (2) Ural Division, Russian Academy of Sciences, Institute of Human Physiology, Komi Research Center, Syktyvkar, Russia Article History: Registration Date: 11/10/2004

Clinical trials by National Health and Nutrition Examination Surveys are made to assess the potential impact of nutritional intervention with folic acid and vitamin B, and to know the risk of increasing cardiovascular diseases on fortification of vitamin B. The study reveals that vitamin B fortification may not reduce cardiovascular disease.

The reports regarding vitamin B(sub12a) or aquacobalamin that binds to NO to produce a nitrosyl complex reaction, which plays an important role in various biological processes is presented. A careful study of the system shows that there is no binding and the presence of nitrite impurities in aqueous solutions of NO produce the nitrite complex reaction.

A potential new member of the vitamin B family has been announced. Scientists reporting in Nature (2003;422:832) say that pyrroloquinoline quinone (PQQ) qualifies as a new vitamin because it plays [...]

Careful scrutiny of data from NHANES III, a recent nationwide health and nutrition survey, showed that fortification of grain products with the B vitamin folate may help reduce memory loss [...]