title: Glycyrrhizin attenuates Toll like receptor-2, -4 and experimental vasospasm in a rat model.
abstract: Upregulated TLRs are observed in the serum of animals following experimental subarachnoid hemorrhage. This study was to examine glycyrrhizin's effect on proinflammatory cytokines and TLRs in SAH rats. Administration with glycyrrhizin was initiated 24 hr before and 1 hr later using osmotic minipump. Basilar arteries were harvested to examine TLRs mRNA and protein (rt-PCR and western blot) and CSF cytokines (rt-PCR). Morphologically, deformed endothelium, tortuous elastic lamina, and smooth muscle necrosis were observed in the SAH rats, but were absent in the glycyrrhizin pretreatment group. The TLR-3 protein level was not increased in SAH animals, compared with the controls, while that of TLR-2 and -4 in the SAH only and SAH plus vehicle groups was significantly elevated (P < 0.01). Pretreatment and treatment with glycyrrhizin reduced TLR-2 and -4 by 28 ± 8% and 33.4 ± 9.2%, respectively. Likewise, glycyrrhizin was able to reduce the IL-1β and MCP-1 mRNA levels. This study shows glycyrrhizin exerts anti-inflammatory effects on SAH induced vasospasm and attenuates the ultrashort time expression of TLRs, like TLR-2 and -4. It corresponds to SAH induced early brain injury. These findings offer credit to the antivasospastic effect of glycyrrhizin and its effect on SAH induced early brain injury.
authors.affiliation: Department of Surgery, Faculty of Medicine, School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan ; Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan ; Department of Surgery, Kaohsiung Municipal Ta Tung Hospital, Kaohsiung, Taiwan.
authors.forename: Chih-Zen
authors.initials: CZ
authors.lastname: Chang
authors.affiliation: Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Shu-Chuan
authors.initials: SC
authors.lastname: Wu
authors.affiliation: Department of Surgery, Faculty of Medicine, School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan ; Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Aij-Lie
authors.initials: AL
authors.lastname: Kwan
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001488:Basilar Artery / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D015870:Gene Expression; D019695:Glycyrrhizic Acid / Q000494:pharmacology*; D008297:Male; D051381:Rats; D013345:Subarachnoid Hemorrhage / Q000150:complications; D051195:Toll-Like Receptor 2 / Q000235:genetics / Q000378:metabolism*; D051196:Toll-Like Receptor 3 / Q000235:genetics / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000235:genetics / Q000378:metabolism*; D020301:Vasospasm, Intracranial / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism*
chemical_list: D000893:Anti-Inflammatory Agents; D018932:Chemokine CCL2; D016207:Cytokines; D051195:Toll-Like Receptor 2; D051196:Toll-Like Receptor 3; D051197:Toll-Like Receptor 4; D019695:Glycyrrhizic Acid