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Objective: To evaluate the relationship between folate, cobalamin (Cbl), and homocysteine (Hcy), and markers of inflammation and oxidative stress within the periphery and central nervous system (CNS) of a healthy human cohort. Methods: Thirty-five matched cerebrospinal fluid (CSF) and plasma samples were collected from consenting participants who required a spinal tap for the administration of anaesthetic. Plasma concentrations of Hcy and both plasma and CSF levels of folate, Cbl, nicotinamide adenine dinucleotide (NAD(H)) and markers of inflammation (interleukin-6, IL-6), and oxidative stress (F2-isoprostanes, 8-hydroxy-2′-deoxyguanosine (8-OHdG), and total antioxidant capacity (TAC)) were quantified. Results: In the peripheral circulation, positive associations were observed between plasma folate and Cbl, and plasma TAC (P ≤ 0.01; P ≤ 0.01) and plasma NAD(H) (P ≤ 0.05; P ≤ 0.05) levels, respectively. Plasma folate was inversely associated with plasma Hcy concentrations (P ≤ 0.05); however, no statistically significant relationships were observed between plasma Hcy and plasma markers of inflammation, oxidative stress, or [NAD(H)]. Within the CNS plasma Hcy correlated positively with CSF IL-6 (P ≤ 0.01) and negatively with CSF NAD(H) (P ≤ 0.05) concentrations. An inverse association was observed between CSF folate and CSF levels of IL-6 (P ≤ 0.05). Unexpectedly, a positive association between CSF Cbl and CSF 8-OHdG levels was also found (P ≤ 0.01). Discussion: These results indicate that folate and Cbl concentrations may influence the levels of oxidative damage, inflammation, and NAD(H), both systemically and within the CNS. [ABSTRACT FROM AUTHOR]

Background The consumption of foods rich in carotenoids that possess significant antioxidant and inflammatory modulating properties has been linked to reduced risk of neuropathology. The objective of this study was to evaluate the relationship between plasma carotenoid concentrations and plasma and cerebrospinal fluid (CSF) markers of inflammation, oxidative stress and nicotinamide adenine dinucleotide (NAD+) in an essentially healthy human cohort. Methods Thirty-eight matched CSF and plasma samples were collected from consenting participants who required a spinal tap for the administration of anaesthetic. Plasma concentrations of carotenoids and both plasma and cerebrospinal fluid (CSF) levels of NAD(H) and markers of inflammation (IL-6, TNF-α) and oxidative stress (F2-isoprostanes, 8-OHdG and total antioxidant capacity) were quantified. Results The average age of participants was 53 years (SD = 20, interquartile range = 38). Both α- carotene (P = 0.01) and β-carotene (P < 0.001) correlated positively with plasma total antioxidant capacity. A positive correlation was observed between α-carotene and CSF TNF- α levels (P = 0.02). β-cryptoxanthin (P = 0.04) and lycopene (P = 0.02) inversely correlated with CSF and plasma IL-6 respectively. A positive correlation was also observed between lycopene and both plasma (P < 0.001) and CSF (P < 0.01) [NAD(H)]. Surprisingly no statistically significant associations were found between the most abundant carotenoids, lutein and zeaxanthin and either plasma or CSF markers of oxidative stress. Conclusion Together these findings suggest that consumption of carotenoids may modulate inflammation and enhance antioxidant defences within both the central nervous system (CNS) and systemic circulation. Increased levels of lycopene also appear to moderate decline in the essential pyridine nucleotide [NAD(H)] in both the plasma and the CSF. [ABSTRACT FROM AUTHOR]

Background: In recent years the physiological and pathological importance of fatty acids in both the periphery and central nervous system (CNS) has become increasingly apparent. However surprisingly limited research has been conducted comparing the fatty acid composition of central and peripheral lipid stores. Methods: The present study compared the distribution of polyunsaturated (PUFA), as well as specific saturated (SFA) and monounsaturated (MUFA) fatty acids in the whole blood and cerebrospinal fluid (CSF) of humans. Gas chromatography with flame ionization detection was used to determine the fatty acid profiles of twenty-eight matched CSF and whole blood samples. Multiple linear regression modeling, controlling for age, was used to identify significant relationships. Results: A significant positive relationship was seen between whole blood total omega-3 fatty acids and the CSF omega-3 subfractions, docosapentaenoic acid (DPA) (P = 0.019) and docosahexaenoic acid (DHA) (P = 0.015). A direct association was also observed between the whole blood and CSF omega-6 PUFA, arachidonic acid (AA) (P = 0.045). Interestingly an inverse association between central and peripheral oleic acid was also found (P = 0.045). Conclusions: These findings indicate a relationship between central and peripheral fatty acids of varying degrees of unsaturation and chain length and support the view that some systemic fatty acids are likely to cross the human blood brain barrier (BBB) and thereby influence central fatty acid concentrations. [ABSTRACT FROM AUTHOR]