Molecular Mechanisms of Drug Transport via Peptide Transporters.

Cyclic Peptide–Selenium Nanoparticles as Drug Transporters

A cyclic peptide composed of five tryptophan, four arginine, and one cysteine [W5R4C] was synthesized. The peptide was evaluated for generating cyclic peptide-capped selenium nanoparticles (CP-SeNPs) in situ. A physical mixing of the cyclic peptide with SeO3(-2) solution in water generated [W5R4C]-SeNPs via the combination of reducing and capping properties of amino acids in the peptide structu...

A rapid in vitro screening for delivery of peptide-derived peptidase inhibitors as potential drug candidates via epithelial peptide transporters.

Targeting drugs or prodrugs to a specific enzyme by simultaneously targeting cell membrane carriers for efficient transport should provide the highest bioavailability along with specificity at the site of action. The peptide transporters PEPT1 and PEPT2 are expressed in a variety of tissues, including the brush-border membranes of epithelial cells of the small intestine and kidney. The transpor...

Molecular mechanisms of cystine transport.

The transport of L-cystine into cells of the mammalian brain is an essential step in the supply of cysteine for synthesis of the antioxidant glutathione. Uptake of L-cystine in rat brain synaptosomes occurs by three mechanisms that are distinguishable on the basis of their ionic dependence, kinetics of transport and specificity of inhibitors. Almost 90% of L-cystine transport is by a low-affini...

Molecular mechanisms of drug resistance.

Molecular mechanisms of drug addiction.

Regulation of gene expression is one mechanism by which drugs of abuse can induce relatively long-lasting changes in the brain to cause a state of addiction. Here, we focus on two transcription factors, CREB (cAMP response element binding protein) and DeltaFosB, which contribute to drug-induced changes in gene expression. Both are activated in the nucleus accumbens, a major brain reward region,...