Cerebrovascular P-glycoprotein (P-gp) acts at the blood-brain barrier (BBB) as an active cell membrane efflux pump for several endogenous and exogenous compounds. Age-associated decline in P-gp function could facilitate the accumulation of toxic substances in the brain, thus increasing the risk of neurodegenerative pathology with aging. We hypothesised a regionally reduced BBB P-gp function in older healthy subjects. We studied cerebrovascular P-gp function using [(11)C]-verapamil positron emission tomography (PET) in seventeen healthy volunteers with age 18-86. Logan analysis was used to calculate the distribution volume (DV) of [(11)C]-verapamil in the brain. Statistical Parametric Mapping was used to study specific regional differences between the older compared with the younger adults. Older subjects showed significantly decreased P-gp function in internal capsule and corona radiata white matter and in orbitofrontal regions. Decreased BBB P-gp function in those regions could thus explain part of the vulnerability of the aging brain to white matter degeneration. Moreover, decreased BBB P-gp function with aging could be a mechanism by which age acts as the main risk factor for the development of neurodegenerative disease.
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http://dx.doi.org/10.1016/j.neurobiolaging.2008.02.002 | DOI Listing |
Mol Imaging Biol
January 2025
Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
Purpose: This preclinical study explored the feasibility of assessing P-glycoprotein (P-gp) function in both brain and gastrointestinal (GI) tract of rats using positron emission tomography (PET) following oral administration of [F]MC225. Different oral administration protocols were evaluated, and radioactivity uptake was compared with uptake following intravenous administration.
Procedures: Twelve male Wistar rats were divided into four groups and subjected to intravenous or oral [F]MC225 administration protocols: G (intravenous route), G (oral administration without fasting), G (oral administration with fasting), and G (oral administration with fasting following administration of the P-gp inhibitor tariquidar).
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
January 2025
National Key Laboratory of Bioreactors, School of Biological Engineering, East China University of Science and Technology, Shanghai 200237, China. *Corresponding author, E-mail:
Eur J Med Chem
January 2025
Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, Atlanta, GA, 30322, United States. Electronic address:
Monoacylglycerol lipase (MAGL) is a 33 kDa cytosolic serine hydrolase that is widely distributed in the central nervous system and peripheral tissues. MAGL hydrolyzes monoacylglycerols into fatty acids and glycerol, playing a crucial role in endocannabinoid degradation. Inhibition of MAGL in the brain elevates levels of 2-arachidonoylglycerol and leads to decreased pro-inflammatory prostaglandin and thromboxane production.
View Article and Find Full Text PDFVet Q
December 2025
Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, Canada.
This review examines the role of the canine blood-brain barrier (BBB) in health and disease, focusing on the impact of the multidrug resistance (MDR) transporter P-glycoprotein (P-gp) encoded by the gene. The BBB is critical in maintaining central nervous system homeostasis and brain protection against xenobiotics and environmental drugs that may be circulating in the blood stream. We revise key anatomical, histological and functional aspects of the canine BBB and examine the role of the gene mutation in specific dog breeds that exhibit reduced P-gp activity and disrupted drug brain pharmacokinetics.
View Article and Find Full Text PDFSci Rep
January 2025
Pharmacy Department, University Clinical Hospital of Santiago de Compostela (SERGAS), 15706, Santiago de Compostela, Spain.
Aripiprazole (ARI) is an atypical antipsychotic which is a substrate of P-glycoprotein (P-gp), a transmembrane glycoprotein that plays a crucial role in eliminating potentially harmful compounds from the organism. ARI once-monthly (AOM) is a long-acting injectable form which improves treatment compliance. Genetic polymorphisms in ABCB1 may lead to changes in P-gp function, leading to individual differences in drug disposition.
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