Takafumi Nakano1, Yoshihiko Nakamura2, Keiichi Irie3, Shinobu Okano4, Mayuka Morimoto4, Yuta Yamashita4, Tomohiro Kozako5, Toshinobu Hayashi6, Shin-Ichiro Honda5, Koichi Matsuo7, Hidetoshi Kamimura6, Hiroyasu Ishikura2, Takashi Egawa7, Kenichi Mishima4. 1. Department of Pharmaceutical and Healthcare Management, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan; Department of Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan; Department of Pharmacy, Fukuoka University Hospital, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0133, Japan. 2. Department of Emergency and Critical Care Medicine, Fukuoka University Hospital, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0133, Japan. 3. Department of Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan. Electronic address: kirie@cis.fukuoka-u.ac.jp. 4. Department of Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan. 5. Department of Biochemistry, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan. 6. Department of Pharmaceutical and Healthcare Management, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan; Department of Pharmacy, Fukuoka University Hospital, 7-45-1 Nanakuma, Jonan-ku, Fukuoka 814-0133, Japan. 7. Department of Pharmaceutical and Healthcare Management, Faculty of Pharmaceutical Sciences, Fukuoka University, 8-19-1 Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan.
Abstract
AIMS: Thrombin formation is increased in patients with acute cerebral ischemic stroke, and augments coagulation and inflammation in the brain. Administration of antithrombin (AT) was previously reported to be protective against renal and myocardial ischemic injury. Thus, we hypothesized that treatment with AT would be neuroprotective against cerebral ischemic injury. This study evaluated the effects of AT treatment on ischemic inflammation and brain damage in mice subjected to middle cerebral artery occlusion (MCAO). MAIN METHODS: A mouse model of 4-hour MCAO was used to induce ischemic brain injury. Recombinant AT gamma was administered intravenously immediately after reperfusion at 4 h after MCAO. Infarct volume, neurological deficit, and regional cerebral blood flow (rCBF) were measured at 24 h after MCAO. To evaluate the effect of AT gamma on ischemic inflammation, we measured the number of Iba1-positive cells (marker of macrophage/microglial activation) and levels of proinflammatory cytokines. Further, we investigated the direct anti-inflammatory effects of rAT in the J774.1 cell line. KEY FINDINGS: Treatment with AT gamma (480 U/kg) reduced infarct volume and neurological deficit, and improved rCBF, in MCAO mice. Moreover, AT gamma treatment decreased the number of Iba1-positive cells and levels of proinflammatory cytokines. In vitro, treatment with thrombin significantly increased proinflammatory cytokine levels, which was significantly reduced by pretreatment with AT gamma. SIGNIFICANCE: Treatment with AT showed neuroprotective effects via anticoagulation actions, as well as direct anti-inflammatory effects on macrophage/microglial activation. These data suggest that AT may be a useful new therapeutic option for cerebral ischemia.
AIMS: Thrombin formation is increased in patients with acute cerebral ischemic stroke, and augments coagulation and inflammation in the brain. Administration of antithrombin (AT) was previously reported to be protective against renal and myocardial ischemic injury. Thus, we hypothesized that treatment with AT would be neuroprotective against cerebral ischemic injury. This study evaluated the effects of AT treatment on ischemic inflammation and brain damage in mice subjected to middle cerebral artery occlusion (MCAO). MAIN METHODS: A mouse model of 4-hour MCAO was used to induce ischemic brain injury. Recombinant AT gamma was administered intravenously immediately after reperfusion at 4 h after MCAO. Infarct volume, neurological deficit, and regional cerebral blood flow (rCBF) were measured at 24 h after MCAO. To evaluate the effect of AT gamma on ischemic inflammation, we measured the number of Iba1-positive cells (marker of macrophage/microglial activation) and levels of proinflammatory cytokines. Further, we investigated the direct anti-inflammatory effects of rAT in the J774.1 cell line. KEY FINDINGS: Treatment with AT gamma (480 U/kg) reduced infarct volume and neurological deficit, and improved rCBF, in MCAOmice. Moreover, AT gamma treatment decreased the number of Iba1-positive cells and levels of proinflammatory cytokines. In vitro, treatment with thrombin significantly increased proinflammatory cytokine levels, which was significantly reduced by pretreatment with AT gamma. SIGNIFICANCE: Treatment with AT showed neuroprotective effects via anticoagulation actions, as well as direct anti-inflammatory effects on macrophage/microglial activation. These data suggest that AT may be a useful new therapeutic option for cerebral ischemia.