title: PACAP and a novel stable analog protect rat brain from ischemia: Insight into the mechanisms of action.
abstract: Pituitary adenylate cyclase-activating polypeptide (PACAP) shows potent protective effects in numerous models of neurological insults. However, the use of PACAP as a clinically efficient drug is limited by its poor metabolic stability. By combining identification of enzymatic cleavage sites with targeted chemical modifications, a metabolically stable and potent PACAP38 analog was recently developed. The neuroprotective activity of this novel compound was for the first time evaluated and compared to the native peptide using a rat model of middle cerebral artery occlusion (MCAO). Our results show that as low as picomolar doses of PACAP38 and its analog strongly reduce infarct volume and improve neurological impairment induced by stroke. In particular, these peptides inhibit the expression of Bcl-2-associated death promoter, caspase 3, macrophage inflammatory protein-1α, inducible nitric oxide synthase 2, tumor necrosis factor-α mRNAs, and increase extracellular signal-regulated kinase 2, B-cell CLL/lymphoma 2 and interleukin 6 mRNA levels. These results indicate that the neuroprotective effect of PACAP after MCAO is not only due to its ability to inhibit apoptosis but also to modulate the inflammatory response. The present study highlights the potential therapeutic efficacy of very low concentrations of PACAP or its metabolically stable derivative for the treatment of stroke.
authors.affiliation: INSERM U982, 76821 Mont-Saint-Aignan, France.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Dejda
authors.forename: Tommy
authors.initials: T
authors.lastname: Seaborn
authors.forename: Steve
authors.initials: S
authors.lastname: Bourgault
authors.forename: Omar
authors.initials: O
authors.lastname: Touzani
authors.forename: Alain
authors.initials: A
authors.lastname: Fournier
authors.forename: Hubert
authors.initials: H
authors.lastname: Vaudry
authors.forename: David
authors.initials: D
authors.lastname: Vaudry
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology*; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004355:Drug Stability; D015870:Gene Expression; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism / Q000473:pathology; D007249:Inflammation / Q000188:drug therapy / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D007511:Ischemia / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D019402:Macrophage Inflammatory Proteins / Q000235:genetics / Q000378:metabolism; D008297:Male; D018696:Neuroprotective Agents / Q000008:administration & dosage* / Q000138:chemical synthesis; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000008:administration & dosage* / Q000138:chemical synthesis; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020521:Stroke / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D019402:Macrophage Inflammatory Proteins; D018696:Neuroprotective Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D051028:bcl-2-Associated X Protein; D053148:Caspase 3