title: In vitro and in vivo efficacy of a potent opioid receptor agonist, biphalin, compared to subtype-selective opioid receptor agonists for stroke treatment.
abstract: To meet the challenge of identification of new treatments for stroke, this study was designed to evaluate a potent, nonselective opioid receptor (OR) agonist, biphalin, in comparison to subtype selective OR agonists, as a potential neuroprotective drug candidate using in vitro and in vivo models of ischemic stroke. Our in vitro approach included mouse primary neuronal cells that were challenged with glutamate and hypoxic/aglycemic (H/A) conditions. We observed that 10nM biphalin, exerted a statistically significant neuroprotective effect after glutamate challenge, compared to all selective opioid agonists, according to lactate dehydrogenase (LDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Moreover, 10nM biphalin provided superior neuroprotection after H/A-reoxygenation compared to selective opioid agonists in all cases. Our in vitro investigations were supported by in vivo studies which indicate that the nonselective opioid agonist, biphalin, achieves enhanced neuroprotective potency compared to any of the selective opioid agonists, evidenced by reduced edema and infarct ratios. Reduction of edema and infarction was accompanied by neurological improvement of the animals in two independent behavioral tests. Collectively these data strongly suggest that concurrent agonist stimulation of mu, kappa and delta ORs with biphalin is neuroprotective and superior to neuroprotection by activation of any single OR subtype.
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S Coulter Drive, Amarillo, TX 79106, USA; Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA.
authors: Li
authors: L
authors: Yang
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S Coulter Drive, Amarillo, TX 79106, USA; Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA.
authors: Mohammad R
authors: MR
authors: Islam
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S Coulter Drive, Amarillo, TX 79106, USA; Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA.
authors: Vardan T
authors: VT
authors: Karamyan
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 S Coulter Drive, Amarillo, TX 79106, USA; Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA. Electronic address: thomas.abbruscato@ttuhsc.edu.
authors: Thomas J
authors: TJ
authors: Abbruscato
mesh_terms: D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer / Q000737:chemistry / Q000494:pharmacology; D000701:Analgesics, Opioid / Q000737:chemistry / Q000494:pharmacology*; D001929:Brain Edema / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D020520:Brain Infarction / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D002478:Cells, Cultured; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)- / Q000737:chemistry / Q000494:pharmacology; D020881:Enkephalin, D-Penicillamine (2,5)- / Q000737:chemistry / Q000494:pharmacology; D004745:Enkephalins / Q000737:chemistry / Q000494:pharmacology*; D018698:Glutamic Acid / Q000633:toxicity; D007511:Ischemia / Q000188:drug therapy / Q000473:pathology; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D018696:Neuroprotective Agents / Q000737:chemistry / Q000494:pharmacology*; D017465:Receptors, Opioid, delta / Q000819:agonists / Q000378:metabolism; D017473:Receptors, Opioid, kappa / Q000819:agonists / Q000378:metabolism; D017450:Receptors, Opioid, mu / Q000819:agonists / Q000378:metabolism; D015427:Reperfusion Injury / Q000188:drug therapy / Q000473:pathology; D012720:Severity of Illness Index; D020521:Stroke / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology
chemical_list: D000701:Analgesics, Opioid; D004745:Enkephalins; D018696:Neuroprotective Agents; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D018698:Glutamic Acid; D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; C053673:biphalin; D020881:Enkephalin, D-Penicillamine (2,5)-
keywords: Blood–brain barrier; Neuropeptide; Neuroprotection; Opioid receptors; Stroke