title: Allicin protects rat cortical neurons against mechanical trauma injury by regulating nitric oxide synthase pathways.
abstract: Allicin, a small molecule that is responsible for the typical smell and most of the functions of garlic, possesses a broad spectrum of pharmacological activities and is considered to have therapeutic potential in many pathologic conditions. In the present study, we investigated the potential protective effect of allicin in an in vitro model of traumatic brain injury (TBI) using primary cultured rat cortical neurons. We found that allicin treatment significantly reduced mechanical trauma-induced lactate dehydrogenase (LDH) release and inhibited apoptotic neuronal death in a dose-dependent manner. These protective effects were observed even if allicin treatment was delayed to 2h after injury. Allicin significantly decreased the expression of inducible nitric oxide synthase (iNOS) and increased the phosphorylation of endothelial NOS (eNOS) but had no effect on neuronal NOS (nNOS) expression. Allicin-induced protection in cortical neurons was augmented by iNOS and nNOS antagonists and was partly reversed by blocking eNOS phosphorylation. In addition, allicin treatment inhibited the TBI-induced activation of ERK and further enhanced the phosphorylation of Akt in TBI-injured neurons. The Akt inhibitor LY294002 attenuated the allicin-induced increase in eNOS expression and phosphorylation, whereas the ERK inhibitor PD98059 had opposite effects on the expression of iNOS and eNOS. Pretreatment with LY294002 or PD98059 partly prevented or further enhanced allicin-induced neuroprotection, respectively. Collectively, these data demonstrate that allicin treatment may be an effective therapeutic strategy for traumatic neuronal injury and that the potential underlying mechanism involves Akt- and ERK-mediated regulation of NOS pathways.
authors.affiliation: Department of Neurosurgery, Xijing Institute of Clinical Neuroscience, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
authors.forename: Yue-fei
authors.initials: YF
authors.lastname: Zhou
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China.
authors.forename: Wen-tao
authors.initials: WT
authors.lastname: Li
authors.affiliation: Department of Cadre Ward, Xi'an Central Hospital, Xi'an, Shaanxi 710000, China.
authors.forename: Hong-cheng
authors.initials: HC
authors.lastname: Han
authors.affiliation: Department of Neurosurgery, Xijing Institute of Clinical Neuroscience, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
authors.forename: Da-kuan
authors.initials: DK
authors.lastname: Gao
authors.affiliation: Department of Neurosurgery, Xijing Institute of Clinical Neuroscience, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
authors.forename: Xiao-sheng
authors.initials: XS
authors.lastname: He
authors.affiliation: Department of Neurosurgery, Xijing Institute of Clinical Neuroscience, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, The First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China. Electronic address: jinnings@126.com.
authors.forename: Jin-ning
authors.initials: JN
authors.lastname: Song
authors.affiliation: Department of Neurosurgery, Xijing Institute of Clinical Neuroscience, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi 710032, China. Electronic address: fmmuzhoufei@163.com.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Fei
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001930:Brain Injuries / Q000188:drug therapy* / Q000378:metabolism; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000187:drug effects / Q000293:injuries; D004195:Disease Models, Animal; D004220:Disulfides; D004789:Enzyme Activation / Q000187:drug effects; D020287:In Situ Nick-End Labeling; D009474:Neurons / Q000187:drug effects*; D018696:Neuroprotective Agents / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D013441:Sulfinic Acids / Q000494:pharmacology*
chemical_list: D004220:Disulfides; D018696:Neuroprotective Agents; D013441:Sulfinic Acids; C006452:allicin; D019001:Nitric Oxide Synthase
keywords: Akt; ERK; Nitric oxide synthase; Traumatic brain injury