Current Pharmaceutical Design - Volume 17, Issue 26, 2011

The delivery of pharmacological compounds to the injured brain is a huge challenge, which may predispose to drug failure and resistance. Besides the limited passage of drugs across the blood-brain barrier, which is a physical obstacle for the majority of pharmacological compounds, brain capillary cells express ATP-binding cassette (ABC) transporters on their surface, which actively remove drugs from the brain against con Read More

The neurovascular unit (NVU), consisting of endothelial cells, basement membrane, pericytes, astrocytes and microglial cells, couples local neuronal function to local cerebral blood flow and regulates transport of blood-borne molecules across the blood-brain barrier (BBB). The building blocks and the phenotype of the NVU are well-established but the intercellular signaling between the different components remains elusi Read More

Proper understanding of blood-brain barrier (BBB) regulation is crucial to reduce/prevent its disruption during injury. Since high brain complexity makes interpretation of in vivo data challenging BBB studies are frequently performed using simplified in vitro models. Although such models represent an important and frequently employed alternative for investigation of BBB function and alterations, our ability to translate in v Read More

According to the World Health Organization Central nervous system disorders are the major medical challenge of the 21st Century, yet treatments for many CNS disorders are either inadequate or absent. One reason is the existence of the blood-brain barrier, which strictly limits the access of substances to the brain. A key element of the barrier function is the expression of ABC export proteins in the luminal membrane of brain Read More

Protection of the brain is strengthened by active transport and ABC transporters. P-glycoprotein (P-gp) at the blood-brain barrier (BBB) functions as an active efflux pump by extruding a substrate from the brain, which is important for maintaining loco-regional homeostasis in the brain and protection against toxic compounds. Importantly, dysfunctional BBB P-gp transport is postulated as an important factor contributing to a Read More

The blood-brain barrier (BBB) protects the brain against endogenous and exogenous compounds and plays an important part in the maintenance of the microenvironment of the brain. In particular, the importance of brain-to-blood transport of brain-derived metabolites across the BBB has gained increasing attention as a potential mechanism in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease, Read More

Ischaemic stroke is one of the most common diseases world-wide. Recent studies provide new insights into the role of ATPbinding cassette (ABC) transporters in brain ischaemia. Expressional and functional transporter changes that have been observed at the brain capillary endothelium during ischaemia impede the access of pharmacological compounds into the brain tissue. The current review summarizes the most important f Read More

Brain cancer is a devastating disease. Despite extensive research, treatment of brain tumors has been largely ineffective and the diagnosis of brain cancer remains uniformly fatal. Failure of brain cancer treatment may be in part due to limitations in drug delivery, influenced by the ABC drug efflux transporters P-gp and BCRP at the blood-brain and blood-tumor barriers, in brain tumor cells, as well as in brain tumor stem-like c Read More

Owing to therapeutic progress, the role of ABC-transporters in infectious and autoimmune inflammatory CNS-diseases has recently gained considerable attention. In HIV-encephalitis and HIV-associated neurocognitive disorders, ABC-transporters are discussed to contribute to limited CNS-penetration and -retention of antiviral agents. In multiple sclerosis and its animal model experimental autoimmune encephalomyeli Read More

Resistance to multiple antiepileptic drugs (AEDs) is a common problem in epilepsy, affecting at least 30% of patients. One prominent hypothesis to explain this resistance suggests an inadequate penetration or excess efflux of AEDs across the blood-brain barrier (BBB) as a result of overexpressed efflux transporters such as P-glycoprotein (Pgp), the encoded product of the multidrug resistance- 1 (MDR1, ABCB1) gen Read More

Some of the ATP-binding cassette (ABC) transporters like P-glycoprotein (P-gp; ABCB1, MDR1), BCRP (ABCG2) and MRPs (ABCCs) that are present at the blood-brain barrier (BBB) influence the brain pharmacokinetics (PK) of their substrates by restricting their uptake or enhancing their clearance from the brain into the blood, which has consequences for their CNS pharmacodynamics (PD). Opioid drugs have been invaluable tools f Read More

Polymorphisms in the drug transporter gene ABCB1 account for differences in the clinically efficacy of the most drugs, most likely by influencing their access to the brain. The majority proportion of depressed patients, given a regular dose, do not respond properly or experience severe side effects. One explanation may be the polymorphisms in the drug transporter gene ABCB1, which account for differences in the clinical eff Read More