Yun Sun1, John W Calvert, John H Zhang. 1. Department of Neurosurgery, Louisiana State University Health Sciences Center, Shreveport, LA, USA.
Abstract
BACKGROUND AND PURPOSE: Erythropoietin (EPO), a hematopoietic growth factor, has been shown to be neuroprotective when administered as either a pretreatment or posttreatment. This study tested the hypothesis that one of the mechanisms of protection afforded by posttreatment with recombinant human EPO (rh-EPO) is an anti-inflammatory effect via inhibition of interleukin (IL)-1beta. METHODS: Seven-day-old rat pups were subjected to unilateral carotid artery ligation followed by 90 minutes of hypoxia (8% O2 at 37 degrees C). Pups were divided into the following groups: control, hypoxia/ischemia, and hypoxia/ischemia plus rh-EPO. In the rh-EPO-treated pups, rh-EPO (5 U/g body weight IP) was administered starting 24 hours after the insult and then for 2 additional days. Samples were collected at 3, 7, 14, and 21 days after the insult. IL-1beta mRNA and protein levels were determined by quantitative real-time reverse transcription-polymerase chain reaction and ELISA. Tumor necrosis factor (TNF)-alpha mRNA levels were determined by colorimetric microplate assay. RESULTS: rhEPO attenuated brain injury, as assessed by brain weight, and attenuated both the hypoxia/ischemia-induced increases in IL-1beta mRNA and protein levels. TNF-alpha mRNA levels did not increase at 3 to 14 days after the hypoxic/ischemic insult. CONCLUSIONS: Administration of exogenous rh-EPO starting 24 hours after a hypoxic/ischemic insult is neuroprotective in the neonatal rat. This neuroprotective activity prevented the secondary, delayed rise in IL-1beta and attenuated the infiltration of leukocytes into the ipsilateral hemisphere.
BACKGROUND AND PURPOSE:Erythropoietin (EPO), a hematopoietic growth factor, has been shown to be neuroprotective when administered as either a pretreatment or posttreatment. This study tested the hypothesis that one of the mechanisms of protection afforded by posttreatment with recombinant humanEPO (rh-EPO) is an anti-inflammatory effect via inhibition of interleukin (IL)-1beta. METHODS: Seven-day-old rat pups were subjected to unilateral carotid artery ligation followed by 90 minutes of hypoxia (8% O2 at 37 degrees C). Pups were divided into the following groups: control, hypoxia/ischemia, and hypoxia/ischemia plus rh-EPO. In the rh-EPO-treated pups, rh-EPO (5 U/g body weight IP) was administered starting 24 hours after the insult and then for 2 additional days. Samples were collected at 3, 7, 14, and 21 days after the insult. IL-1beta mRNA and protein levels were determined by quantitative real-time reverse transcription-polymerase chain reaction and ELISA. Tumor necrosis factor (TNF)-alpha mRNA levels were determined by colorimetric microplate assay. RESULTS: rhEPO attenuated brain injury, as assessed by brain weight, and attenuated both the hypoxia/ischemia-induced increases in IL-1beta mRNA and protein levels. TNF-alpha mRNA levels did not increase at 3 to 14 days after the hypoxic/ischemic insult. CONCLUSIONS: Administration of exogenous rh-EPO starting 24 hours after a hypoxic/ischemic insult is neuroprotective in the neonatal rat. This neuroprotective activity prevented the secondary, delayed rise in IL-1beta and attenuated the infiltration of leukocytes into the ipsilateral hemisphere.
Authors: Manuela Mengozzi; Ilaria Cervellini; Pia Villa; Zübeyde Erbayraktar; Necati Gökmen; Osman Yilmaz; Serhat Erbayraktar; Mathini Manohasandra; Paul Van Hummelen; Peter Vandenabeele; Yuti Chernajovsky; Alexander Annenkov; Pietro Ghezzi Journal: Proc Natl Acad Sci U S A Date: 2012-05-29 Impact factor: 11.205
Authors: Rhonda Souvenir; Nancy Fathali; Robert P Ostrowski; Tim Lekic; John H Zhang; Jiping Tang Journal: Neurobiol Dis Date: 2011-06-06 Impact factor: 5.996