title: Neuroprotection with an erythropoietin mimetic peptide (pHBSP) in a model of mild traumatic brain injury complicated by hemorrhagic shock.
abstract: Pyroglutamate helix B surface peptide (pHBSP) is an 11 amino acid peptide, designed to interact with a novel cell surface receptor, composed of the classical erythropoietin (EPO) receptor disulfide linked to the beta common receptor. pHBSP has the cytoprotective effects of EPO without stimulating erythropoiesis. Effects on early cerebral hemodynamics and neurological outcome at 2 weeks post-injury were compared in a rat model of mild cortical impact injury (3m/sec, 2.5 mm deformation) followed by 50 min of hemorrhagic hypotension (MAP 40 mm Hg for 50 min). Rats were randomly assigned to receive 5000 U/kg of EPO, 30 μg/kg of pHBSP, or an inactive substance every 12 h for 3 days, starting at the end of resuscitation from the hemorrhagic hypotension, which was 110 min post-injury. Both treatments reduced contusion volume at 2 weeks post-injury, from 20.8±2.8 mm(3) in the control groups to 7.7±2.0 mm(3) in the EPO-treated group and 5.9±1.5 mm(3) in the pHBSP-treated group (p=0.001). Both agents improved recovery of cerebral blood flow in the injured brain following resuscitation, and resulted in more rapid recovery of performance on beam balancing and beam walking tests. These studies suggest that pHBSP has neuroprotective effects similar to EPO in this model of combined brain injury and hypotension. pHBSP may be more useful in the clinical situation because there is less risk of thrombotic adverse effects.
authors.affiliation: Department of Neurosurgery, Baylor College of Medicine, Houston, Texas 77030, USA. claudiar@bcm.edu
authors.forename: Claudia S
authors.initials: CS
authors.lastname: Robertson
authors.forename: Leela
authors.initials: L
authors.lastname: Cherian
authors.forename: Mahek
authors.initials: M
authors.lastname: Shah
authors.forename: Robert
authors.initials: R
authors.lastname: Garcia
authors.forename: Jovany Cruz
authors.initials: JC
authors.lastname: Navarro
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Grill
authors.forename: Carla Cerami
authors.initials: CC
authors.lastname: Hand
authors.forename: Tian Siva
authors.initials: TS
authors.lastname: Tian
authors.forename: H Julia
authors.initials: HJ
authors.lastname: Hannay
mesh_terms: D000818:Animals; D001930:Brain Injuries / Q000150:complications / Q000188:drug therapy*; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004195:Disease Models, Animal; D004921:Erythropoietin / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects*; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology; D051381:Rats; D020318:Rats, Long-Evans; D020127:Recovery of Function / Q000187:drug effects; D012771:Shock, Hemorrhagic / Q000188:drug therapy* / Q000209:etiology
chemical_list: D018696:Neuroprotective Agents; D009842:Oligopeptides; D004921:Erythropoietin