6-Diazo-5-oxo-l-norleucine (DON) is a glutamine antagonist with robust anticancer efficacy; however, its therapeutic potential was hampered by its biodistribution and toxicity to normal tissues, specifically gastrointestinal (GI) tissues. To circumvent DON's toxicity, we synthesized a series of tumor-targeted DON prodrugs designed to circulate inert in plasma and preferentially activate over DON in tumor. Our best prodrug 6 (isopropyl 2-(6-acetamido-2-(adamantane-1-carboxamido)hexanamido)-6-diazo-5-oxohexanoate) showed stability in plasma, liver, and intestinal homogenates yet was readily cleaved to DON in P493B lymphoma cells, exhibiting a 55-fold enhanced tumor cell-to-plasma ratio versus that of DON and resulting in a dose-dependent inhibition of cell proliferation. Using carboxylesterase 1 knockout mice that were shown to mimic human prodrug metabolism, systemic administration of 6 delivered 11-fold higher DON exposure to tumor (target tissue; AUC0- t = 5.1 nmol h/g) versus GI tissues (toxicity tissue; AUC0- t = 0.45 nmol h/g). In summary, these studies describe the discovery of a glutamine antagonist prodrug that provides selective tumor exposure.

• MeSH
• acetylace MeSH
• diazooxonorleucin aplikace a dávkování   farmakokinetika   MeSH
• karboxylesterhydrolasy genetika   MeSH
• lékové transportní systémy * MeSH
• lidé MeSH
• lysin chemie   MeSH
• myši knockoutované MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• plocha pod křivkou MeSH
• prasata MeSH
• prekurzory léčiv chemie   MeSH
• protinádorové látky aplikace a dávkování   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Aberrant excitatory neurotransmission associated with overproduction of glutamate has been implicated in the development of HIV-associated neurocognitive disorders (HAND). The glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON, 14) attenuates glutamate synthesis in HIV-infected microglia/macrophages, offering therapeutic potential for HAND. We show that 14 prevents manifestation of spatial memory deficits in chimeric EcoHIV-infected mice, a model of HAND. 14 is not clinically available, however, because its development was hampered by peripheral toxicities. We describe the synthesis of several substituted N-(pivaloyloxy)alkoxy-carbonyl prodrugs of 14 designed to circulate inert in plasma and be taken up and biotransformed to 14 in the brain. The lead prodrug, isopropyl 6-diazo-5-oxo-2-(((phenyl(pivaloyloxy)methoxy)carbonyl)amino)hexanoate (13d), was stable in swine and human plasma but liberated 14 in swine brain homogenate. When dosed systemically in swine, 13d provided a 15-fold enhanced CSF-to-plasma ratio and a 9-fold enhanced brain-to-plasma ratio relative to 14, opening a possible clinical path for the treatment of HAND.

• MeSH
• aminokapronáty aplikace a dávkování   chemická syntéza   farmakologie   MeSH
• azosloučeniny aplikace a dávkování   chemická syntéza   farmakologie   MeSH
• diazooxonorleucin aplikace a dávkování   farmakologie   MeSH
• glutaminasa antagonisté a inhibitory   MeSH
• HIV infekce komplikace   MeSH
• krev metabolismus   MeSH
• kyselina glutamová metabolismus   MeSH
• lidé MeSH
• mozek metabolismus   MeSH
• myši inbrední C57BL MeSH
• neurokognitivní poruchy farmakoterapie   etiologie   MeSH
• nootropní látky aplikace a dávkování   chemická syntéza   farmakologie   MeSH
• prasata MeSH
• prekurzory léčiv aplikace a dávkování   chemická syntéza   farmakologie   MeSH
• stabilita léku MeSH
• virová nálož účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH