Search

Disturbance of cholesterol homeostasis in the brain is coupled to age-related brain dysfunction. In the present work, we studied the relationship between aging and cholesterol metabolism in two brain regions, the cortex and hippocampus, as well as in the sera and liver of 6-, 12-, 18- and 24-month-old male Wistar rats. Using gas chromatography-mass spectrometry, we undertook a comparative analysis of the concentrations of cholesterol, its precursors and metabolites, as well as dietary-derived phytosterols. During aging, the concentrations of the three cholesterol precursors examined (lanosterol, lathosterol and desmosterol) were unchanged in the cortex, except for desmosterol which decreased (44 %) in 18-month-old rats. In the hippocampus, aging was associated with a significant reduction in lanosterol and lathosterol concentrations at 24 months (28 and 25 %, respectively), as well as by a significant decrease of desmosterol concentration at 18 and 24 months (36 and 51 %, respectively). In contrast, in the liver we detected age-induced increases in lanosterol and lathosterol concentrations, and no change in desmosterol concentration. The amounts of these sterols were lower than in the brain regions. In the cortex and hippocampus, desmosterol was the predominant cholesterol precursor. In the liver, lathosterol was the most abundant precursor. This ratio remained stable during aging. The most striking effect of aging observed in our study was a significant decrease in desmosterol concentration in the hippocampus which could reflect age-related reduced synaptic plasticity, thus representing one of the detrimental effects of advanced age. Ministry of Education, Science and Technological Development of the Republic of Serbia [ON173056]; FWO Pegasus Marie Curie Fellowship

Bruno, O., Fedele, E., Prickaerts, J., Parker, L. A., Canepa, E., Brullo, C., Cavallero, A., Gardella, E., Balbi, A., Domenicotti, C., Bollen, E., Gijselaers, H. J. M., Vanmierlo, T., Erb, K., Limebeer, C. L., Argellati, F., Marinari, U. M., Pronzato, M. A., & Ricciarelli, R. (2011). GEBR-7b, a novel PDE4D selective inhibitor that improves memory in rodents at non-emetic doses. British Journal of Pharmacology, 164, 2054-2063. doi: 10.1111/j.1476-5381.2011.01524.x

Vanmierlo T, Popp J, Kolsch H, Friedrichs S, Jessen F, Stoffel-Wagner B, Bertsch T, Hartmann T, Maier W, von Bergmann K, Steinbusch H, Mulder M, Lutjohann D. The plant sterol brassicasterol as additional CSF biomarker in Alzheimer’s disease. Objective: Plant sterols (sitosterol, campesterol, stigmasterol and brassicasterol) are solely dietary-derivable sterols that are structurally very similar to cholesterol. In contrast to peripheral cholesterol, plant sterols can cross the blood–brain barrier and accumulate within mammalian brain. As an impaired function of the cerebrospinal fluid (CSF)–blood barrier is linked to neurodegenerative disorders, i.e. Alzheimer’s disease (AD), we investigated whether this results in altered plant sterol concentrations in CSF. Method: Applying gas chromatography/mass spectrometry analysis, plant sterol concentrations were measured in plasma and CSF of patients with AD (n = 67) and controls (n = 29). Age, gender, plasma-to-CSF albumin ratio, CSF Aβ42, CSF pTau, APOE4 genotype, and serum creatinine were applied as covariates in the statistical analysis for individual plant sterols in order to compare plasma and CSF plant sterol concentrations between patients with AD and controls. Results: Albumin quotient was a consistent predictor in CSF for cholesterol and methyl plant sterols campesterol and brassicasterol. Comparison of lipid parameters per diagnosis based on relevant predictors revealed significantly lower concentrations of brassicasterol (P