title: Localized and sustained delivery of erythropoietin from PLGA microspheres promotes functional recovery and nerve regeneration in peripheral nerve injury.
abstract: Erythropoietin (EPO) has been demonstrated to exert neuroprotective effects on peripheral nerve injury recovery. Though daily intraperitoneal injection of EPO during a long period of time was effective, it was a tedious procedure. In addition, only limited amount of EPO could reach the injury sites by general administration, and free EPO is easily degraded in vivo. In this study, we encapsulated EPO in poly(lactide-co-glycolide) (PLGA) microspheres. Both in vitro and in vivo release assays showed that the EPO-PLGA microspheres allowed sustained release of EPO within a period of two weeks. After administration of such EPO-PLGA microspheres, the peripheral nerve injured rats had significantly better recovery compared with those which received daily intraperitoneal injection of EPO, empty PLGA microspheres, or saline treatments. This was supported by the functional, electrophysiological, and histological evaluations of the recovery done at week 8 postoperatively. We conclude that sustained delivery of EPO could be achieved by using EPO-PLGA microspheres, and such delivery method could further enhance the recovery function of EPO in nerve injury recovery.
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Medical Department, Affiliated Hospital of Chinese PLA General Hospital, Beijing 100048, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Jianheng
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Licheng
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Anhua
authors.initials: A
authors.lastname: Long
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Lihai
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, General Hospital of Chinese PLA, Beijing 100853, China.
authors.forename: Peifu
authors.initials: P
authors.lastname: Tang
mesh_terms: D000818:Animals; D002214:Capsules / Q000138:chemical synthesis; D003692:Delayed-Action Preparations / Q000008:administration & dosage* / Q000737:chemistry; D004058:Diffusion; D004921:Erythropoietin / Q000008:administration & dosage* / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry*; D008297:Male; D009416:Nerve Regeneration / Q000187:drug effects*; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000737:chemistry; D059348:Peripheral Nerve Injuries / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D051381:Rats; D017207:Rats, Sprague-Dawley; D020127:Recovery of Function / Q000187:drug effects; D016896:Treatment Outcome
chemical_list: D002214:Capsules; D003692:Delayed-Action Preparations; D018696:Neuroprotective Agents; D004921:Erythropoietin; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid
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