title: Enkephalin glycopeptide analogues produce analgesia with reduced dependence liability.
abstract: Endogenous peptides (e.g. enkephalins) control many aspects of brain function, cognition, and perception. The use of these neuroactive peptides in diverse studies has led to an increased understanding of brain function. Unfortunately, the use of brain-derived peptides as pharmaceutical agents to alter brain chemistry in vivo has lagged because peptides do not readily penetrate the blood-brain barrier. Attachment of simple sugars to enkephalins increases their penetration of the blood-brain barrier and allows the resulting glycopeptide analogues to function effectively as drugs. The delta-selective glycosylated Leu-enkephalin amide 2, H(2)N-Tyr-D-Thr-Gly-Phe-Leu-Ser(beta-D-Glc)-CONH(2), produces analgesic effects similar to morphine, even when administered peripherally, yet possesses reduced dependence liability as indicated by naloxone-precipitated withdrawal studies. Similar glycopeptide-based pharmaceuticals hold forth the promise of pain relief with improved side-effect profiles over currently available opioid analgesics.
authors.affiliation: Department of Biological Sciences, University of Northern Colorado, Greeley 80639, USA.
authors.forename: E J
authors.initials: EJ
authors.lastname: Bilsky
authors.forename: R D
authors.initials: RD
authors.lastname: Egleton
authors.forename: S A
authors.initials: SA
authors.lastname: Mitchell
authors.forename: M M
authors.initials: MM
authors.lastname: Palian
authors.forename: P
authors.initials: P
authors.lastname: Davis
authors.forename: J D
authors.initials: JD
authors.lastname: Huber
authors.forename: H
authors.initials: H
authors.lastname: Jones
authors.forename: H I
authors.initials: HI
authors.lastname: Yamamura
authors.forename: J
authors.initials: J
authors.lastname: Janders
authors.forename: T P
authors.initials: TP
authors.lastname: Davis
authors.forename: F
authors.initials: F
authors.lastname: Porreca
authors.forename: V J
authors.initials: VJ
authors.lastname: Hruby
authors.forename: R
authors.initials: R
authors.lastname: Polt
mesh_terms: D000701:Analgesics, Opioid / Q000009:adverse effects / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D005260:Female; D006020:Glycopeptides / Q000009:adverse effects / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D007276:Injections, Intraventricular; D010147:Pain Measurement; D051381:Rats; D017207:Rats, Sprague-Dawley; D017465:Receptors, Opioid, delta / Q000378:metabolism; D017450:Receptors, Opioid, mu / Q000378:metabolism; D013375:Substance Withdrawal Syndrome / Q000209:etiology
chemical_list: D000701:Analgesics, Opioid; D006020:Glycopeptides; D017465:Receptors, Opioid, delta; D017450:Receptors, Opioid, mu; C411155:tyrosyl-threonyl-glycyl--phenylalanyl-leucyl-O-glucosylserinamide; D004743:Enkephalin, Leucine