Brain hemodynamic intermediate phenotype links Vitamin B12 to cognitive profile of healthy and mild cognitive impaired subjects

Vitamin B12, folate, and homocysteine are implicated in pivotal neurodegenerative mechanisms and partake in elders' mental decline. Findings on the association between vitamin-related biochemistry and cognitive abilities suggest that the structural and functional properties of the brain may represent an intermediate biomarker linking vitamin concentrations to cognition. Despite this, no previous study directly investigated whether vitamin B12, folate, and homocysteine levels are sufficient to explain individual neuropsychological profiles or, alternatively, whether the activity of brain regions modulated by these compounds better predicts cognition in elders. Here, we measured the relationship between vitamin blood concentrations, scores at seventeen neuropsychological tests, and brain activity of sixty-five elders spanning from normal to Mild Cognitive Impairment. We then evaluated whether task-related brain responses represent an intermediate phenotype, providing a better prediction of subjects' neuropsychological scores, as compared to the one obtained considering blood biochemistry only. We found that the hemodynamic activity of the right dorsal anterior cingulate cortex was positively associated (p value < 0 05 cluster corrected) with vitamin B12 concentrations, suggesting that elders with higher B12 levels had a more pronounced recruitment of this salience network region. Crucially, the activity of this area significantly predicted subjects' visual search and attention abilities (p value = 0 0023), whereas B12 levels per se failed to do so. Our results demonstrate that the relationship between blood biochemistry and elders' cognitive abilities is revealed when brain activity is included into the equation, thus highlighting the role of brain imaging as intermediate phenotype.Vitamin B12, folate, and homocysteine are implicated in pivotal neurodegenerative mechanisms and partake in elders' mental decline. Findings on the association between vitamin-related biochemistry and cognitive abilities suggest that the structural and functional properties of the brain may represent an intermediate biomarker linking vitamin concentrations to cognition. Despite this, no previous study directly investigated whether vitamin B12, folate, and homocysteine levels are sufficient to explain individual neuropsychological profiles or, alternatively, whether the activity of brain regions modulated by these compounds better predicts cognition in elders. Here, we measured the relationship between vitamin blood concentrations, scores at seventeen neuropsychological tests, and brain activity of sixty-five elders spanning from normal to Mild Cognitive Impairment. We then evaluated whether task-related brain responses represent an intermediate phenotype, providing a better prediction of subjects' neuropsychological scores, as compared to the one obtained considering blood biochemistry only. We found that the hemodynamic activity of the right dorsal anterior cingulate cortex was positively associated (p value < 0 05 cluster corrected) with vitamin B12 concentrations, suggesting that elders with higher B12 levels had a more pronounced recruitment of this salience network region. Crucially, the activity of this area significantly predicted subjects' visual search and attention abilities (p value = 0 0023), whereas B12 levels per se failed to do so. Our results demonstrate that the relationship between blood biochemistry and elders' cognitive abilities is revealed when brain activity is included into the equation, thus highlighting the role of brain imaging as intermediate phenotype

Randomized trial on the effects of a combined physical/cognitive training in aged MCI subjects: the Train the Brain study

Age-related cognitive impairment and dementia are an increasing societal burden. Epidemiological studies indicate that lifestyle factors, e.g. physical, cognitive and social activities, correlate with reduced dementia risk; moreover, positive effects on cognition of physical/cognitive training have been found in cognitively unimpaired elders. Less is known about effectiveness and action mechanisms of physical/cognitive training in elders already suffering from Mild Cognitive Impairment (MCI), a population at high risk for dementia. We assessed in 113 MCI subjects aged 65-89 years, the efficacy of combined physical-cognitive training on cognitive decline, Gray Matter (GM) volume loss and Cerebral Blood Flow (CBF) in hippocampus and parahippocampal areas, and on brain-blood-oxygenation-level-dependent (BOLD) activity elicited by a cognitive task, measured by ADAS-Cog scale, Magnetic Resonance Imaging (MRI), Arterial Spin Labeling (ASL) and fMRI, respectively, before and after 7 months of training vs. usual life. Cognitive status significantly decreased in MCI-no training and significantly increased in MCI-training subjects; training increased parahippocampal CBF, but no effect on GM volume loss was evident; BOLD activity increase, indicative of neural efficiency decline, was found only in MCI-no training subjects. These results show that a non pharmacological, multicomponent intervention improves cognitive status and indicators of brain health in MCI subjects

Occurrence of aflatoxin M1 in commercial pasteurized milk determined with ELISA and HPLC

Eighty‐one samples of commercial pasteurized milk from Athens market were analysed for the presence of aflatoxin M1 (AFM1). A combination of a commercial ELISA kit and a modified HPLC method was applied for the rapid and reliable determination of AFM1. AFM1 concentrations in milk extracts were initially estimated by ELISA. Samples found to contain more than 5 ng/l were further quantitated by HPLC. Determination was performed after derivatization of AFM1to its hydroxylated product AFM2a. The recovery of the HPLC method used was found to be close to 100%. Thirty‐two samples contained aflatoxin M1 at levels of 2.5–5 ng/l, none contained more than 5 ng/l, while 31 contained only traces of aflatoxin (0.5–1 ng/l). In nine samples no AFM1 was detected. There was no seasonal influence on the aflatoxin content of the milk samples analysed. © 1997 Taylor and Francis Group, LLC

Fatty acid composition of Allium species lipids

Fatty acid (FA) composition of the main edible Allium species [onion (Allium cepa), garlic (Allium sativum) and leek (Allium porrum)] is determined by gas chromatography (GC). Total lipids are isolated according to the Kates and Eberhart method and separated into neutral, glycolipids and phospholipids by solid phase extraction chromatography using a silica column. GC analysis of FA is achieved using a BPX70 (SGE) column and an optimized method. Eighty percent of the total lipids of all species consists of four FA: linoleic (46-53%), palmitic (20-23%), oleic (4-13%) and α-linolenic acid (3-7%). In onion, 43 FA are determined, 18 of that above 0.4% and 4 above 2.5%. In garlic, 70 FA are determined, 14 of that above 0.4% and only 4 above 2.5%. In leek, 50 FA are determined, 12 of that above 0.4% and 4 above 2.5%. Phospholipids consist of a limited number of specific FA, while neutral lipids contain a wide range including some unusual FA. © 2005 Elsevier Inc. All rights reserved

Lipid levels in cabbage leaves (Brassica oleracea)

Cabbage (Brassica oleracea L, var Glory) is one of the cruciferous vegetables. The objective of this study was to investigate the neutral, glyco‐ and phospholipids of cabbage and their fatty acid composition. Lipids from its leaves were extracted and fractionated into neutral lipids, glycolipids and phospholipids. The fatty acids of each fraction were analysed by gas liquid chromatography. Copyright © 1990 John Wiley & Sons, Lt

Composition of the essential oil of marjoram (Origanum majorana L.)

The quantitative composition of the essential oil of Origanum majorana L. grown in Greece is reported. A total of 45 compounds were identified by means of gas liquid chromatography and GC-MS analysis. The most prominent component was 4-terpineol (37%) and three substances were identified for the first time in marjoram oils. © 1992