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Pugazenthi S, Norris AJ, Lauzier DC, Lele AV, Huguenard A, Dhar R, Zipfel GJ, Athiraman U. Conditioning-based therapeutics for aneurysmal subarachnoid hemorrhage - A critical review. J Cereb Blood Flow Metab 2024; 44:317-332. [PMID: 38017387 PMCID: PMC10870969 DOI: 10.1177/0271678x231218908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/08/2023] [Accepted: 11/19/2023] [Indexed: 11/30/2023]
Abstract
Aneurysmal subarachnoid hemorrhage (SAH) carries significant mortality and morbidity, with nearly half of SAH survivors having major cognitive dysfunction that impairs their functional status, emotional health, and quality of life. Apart from the initial hemorrhage severity, secondary brain injury due to early brain injury and delayed cerebral ischemia plays a leading role in patient outcome after SAH. While many strategies to combat secondary brain injury have been developed in preclinical studies and tested in late phase clinical trials, only one (nimodipine) has proven efficacious for improving long-term functional outcome. The causes of these failures are likely multitude, but include use of therapies targeting only one element of what has proven to be multifactorial brain injury process. Conditioning is a therapeutic strategy that leverages endogenous protective mechanisms to exert powerful and remarkably pleiotropic protective effects against injury to all major cell types of the CNS. The aim of this article is to review the current body of evidence for the use of conditioning agents in SAH, summarize the underlying neuroprotective mechanisms, and identify gaps in the current literature to guide future investigation with the long-term goal of identifying a conditioning-based therapeutic that significantly improves functional and cognitive outcomes for SAH patients.
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Affiliation(s)
- Sangami Pugazenthi
- Department of Neurological Surgery, Washington University, St. Louis MO, USA
| | - Aaron J Norris
- Department of Anesthesiology, Washington University, St. Louis MO, USA
| | - David C Lauzier
- Department of Neurological Surgery, University of California, Los Angeles, CA, USA
| | - Abhijit V Lele
- Department of Anesthesiology, University of Washington, Seattle, WA, USA
| | - Anna Huguenard
- Department of Neurological Surgery, Washington University, St. Louis MO, USA
| | - Rajat Dhar
- Department of Neurology, Washington University, St. Louis, MO, USA
| | - Gregory J Zipfel
- Departments of Neurological Surgery and Neurology, Washington University, St. Louis, MO, USA
| | - Umeshkumar Athiraman
- Department of Anesthesiology and Neurological Surgery, Washington University, St. Louis, MO, USA
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Chen WW, Sun FQ, Wang B, Tian XX, Zhang RP, Liu WB. T817MA Regulates Mitochondrial Dynamics via Sirt1 and Arc Following Subarachnoid Hemorrhage. Neuroscience 2023; 531:1-11. [PMID: 37385332 DOI: 10.1016/j.neuroscience.2023.06.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 06/14/2023] [Accepted: 06/22/2023] [Indexed: 07/01/2023]
Abstract
Spontaneous subarachnoid hemorrhage (SAH) is an acute neurologic emergency with poor outcomes, and mitochondrial dysfunction is known as one of the key pathological mechanisms underlying the SAH-induced early brain injury (EBI). 1-{3-[2-(1-benzothiophen-5-yl)ethoxy]propyl} azetidin-3-ol maleate (T817MA) is a newly synthesized neurotrophic compound that has been demonstrated to exert protective effects against brain injury. Here, we investigated the effect of T817MA in neuronal injury following experimental SAH both in vitro and in vivo. Primary cultured cortical neurons were treated with oxyhemoglobin (OxyHb) to mimic SAH in vitro, and T817MA at concentrations higher than 0.1 μM reduced OxyHb-induced neuronal injury. T817MA treatment significantly inhibited lipid peroxidation, reduced neuronal apoptosis and attenuated mitochondrial fragmentation. The results of western blot showed that T817MA markedly reduced the expression of mitochondrial fission proteins, fission protein 1 (Fis-1) and dynamin-related GTPase-1 (Drp-1), but prolonged the expression of the postsynaptic protein activity-regulated cytoskeleton-associated protein (Arc). In addition, T817MA significantly increased the expression of sirtuin 1 (Sirt1), which was accompanied by preserved enzymatic of isocitrate dehydrogenase (IDH2) and superoxide dismutase (SOD). Knockdown of Sirt1 and Arc via small interfere RNA (siRNA) transfection partially prevented the T817MA-induced protection in cortical neurons. Furthermore, treatment with T817MA in vivo significantly reduced brain damage and preserved neurological function in rats. The decreased expression of Fis-1 and Drp-1, as well as the increased expression of Arc and Sirt1 were also observed in vivo. Taken together, these data indicate that the neuroprotective agent T817MA protects against SAH-induced brain injury via Sirt1- and Arc-mediated regulation of mitochondrial dynamics.
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Affiliation(s)
- Wei-Wei Chen
- Central Laboratory, The First Affiliated Hospital of Weifang Medical University, Weifang Medical University, Weifang, Shandong 261000, China; Naval Medical Center of PLA, Naval Medical University of PLA, Shanghai 200052, China
| | - Fu-Qiang Sun
- Central Laboratory, The First Affiliated Hospital of Weifang Medical University, Weifang Medical University, Weifang, Shandong 261000, China
| | - Bo Wang
- Central Laboratory, The First Affiliated Hospital of Weifang Medical University, Weifang Medical University, Weifang, Shandong 261000, China
| | - Xiao-Xiao Tian
- Naval Medical Center of PLA, Naval Medical University of PLA, Shanghai 200052, China
| | - Rong-Ping Zhang
- Department of Surgery, Shanghai Songjiang Sijing Hospital, Shanghai 200052, China
| | - Wen-Bo Liu
- Central Laboratory, The First Affiliated Hospital of Weifang Medical University, Weifang Medical University, Weifang, Shandong 261000, China.
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Chen T, Xu YP, Chen Y, Sun S, Yan ZZ, Wang YH. Arc regulates brain damage and neuroinflammation via Sirt1 signaling following subarachnoid hemorrhage. Brain Res Bull 2023; 203:110780. [PMID: 37820952 DOI: 10.1016/j.brainresbull.2023.110780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 10/04/2023] [Accepted: 10/09/2023] [Indexed: 10/13/2023]
Abstract
Aneurysmal subarachnoid hemorrhage (aSAH) accounts for only 5 % of all stroke cases, but carries a heavy burden of morbidity and mortality. Activity regulated cytoskeleton associated protein (Arc) is an immediate early gene (IEG)-coded postsynaptic protein that is involved in synaptic plasticity. Increasing evidence and our previous studies have shown that Arc might be involved in the pathological mechanism of various neurological diseases, such as traumatic brain injury (TBI). In this study, we investigated the level of Arc in cerebrospinal fluids (CSF) of aSAH patients and its potential role in brain damage following experimental SAH model. We found that the levels of Arc in aSAH patients' CSF positively correlated with Hunt-Hess (H&H) grades. Knockdown of endogenous Arc expression by small interfere RNA (siRNA) significantly increased brain edema and oxidative stress following SAH. The results of immunostaining in brain sections showed that knockdown of Arc enhanced activation of microglia and astrocytes. In congruent, generation of inflammatory cytokines following SAH was increased by Si-Arc transfection. The results of western blot analysis showed that knockdown of Arc inhibited the expression of Sirt1 and Nrf2, which was accompanied by decreased enzymatic activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px). In addition, activation of sirtuin 1 (Sirt1) via agonist SRT2104 markedly decreased the brain damage and neuroinflammation induced by Arc knockdown. In conclusion, knockdown of endogenous Arc could aggravate brain damage and neuroinflammation following experimental SAH, and Arc levels in aSAH patients' CSF might be a potential indicator of brain damage and prognosis.
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Affiliation(s)
- Tao Chen
- Department of Neurosurgery, Wuxi Taihu Hospital, Wuxi Clinical College of Anhui Medical University, Wuxi, Jiangsu 214044, China
| | - Ye-Ping Xu
- Department of Neurosurgery, Wuxi Taihu Hospital, Wuxi Clinical College of Anhui Medical University, Wuxi, Jiangsu 214044, China
| | - Yang Chen
- Department of Neurology, Wuxi Taihu Hospital, Wuxi Clinical College of Anhui Medical University, Wuxi, Jiangsu 214044, China
| | - Shu Sun
- Department of Pharmacy, Wuxi Taihu Hospital, Wuxi Clinical College of Anhui Medical University, Wuxi, Jiangsu 214044, China
| | - Zhi-Zhong Yan
- Department of Neurosurgery, Wuxi Taihu Hospital, Wuxi Clinical College of Anhui Medical University, Wuxi, Jiangsu 214044, China
| | - Yu-Hai Wang
- Department of Neurosurgery, Wuxi Taihu Hospital, Wuxi Clinical College of Anhui Medical University, Wuxi, Jiangsu 214044, China.
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Xia D, Yuan J, Wu D, Dai H, Zhuang Z. Salvianolic acid B ameliorates neuroinflammation and neuronal injury via blocking NLRP3 inflammasome and promoting SIRT1 in experimental subarachnoid hemorrhage. Front Immunol 2023; 14:1159958. [PMID: 37564636 PMCID: PMC10410262 DOI: 10.3389/fimmu.2023.1159958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 07/05/2023] [Indexed: 08/12/2023] Open
Abstract
The nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated immuno-inflammatory response plays a critical role in exacerbating early brain injury (EBI) after subarachnoid hemorrhage (SAH). Salvianolic acid B (SalB) has previously been shown to suppress neuroinflammatory responses in many disorders. Meanwhile, a previous study has demonstrated that SalB mitigated oxidative damage and neuronal degeneration in a prechiasmatic injection model of SAH. However, the therapeutic potential of SalB on immuno-inflammatory responses after SAH remains unclear. In the present study, we explored the therapeutic effects of SalB on neuroinflammatory responses in an endovascular perforation SAH model. We observed that SalB ameliorated SAH-induced functional deficits. Additionally, SalB significantly mitigated microglial activation, pro-inflammatory cytokines release, and neuronal injury. Mechanistically, SalB inhibited NLRP3 inflammasome activation and increased sirtuin 1 (SIRT1) expression after SAH. Administration of EX527, an inhibitor of SIRT1, abrogated the anti-inflammatory effects of SalB against SAH and further induced NLRP3 inflammasome activation. In contrast, MCC950, a potent and selective NLRP3 inflammasome inhibitor, reversed the detrimental effects of SIRT1 inhibition by EX527 on EBI. These results indicated that SalB effectively repressed neuroinflammatory responses and neuronal damage after SAH. The action of SalB appeared to be mediated by blocking NLRP3 inflammasome and promoting SIRT1 signaling.
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Affiliation(s)
- Dayong Xia
- The Translational Research Institute for Neurological Disorders of Wannan Medical College, Department of Neurosurgery, the First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Jinlong Yuan
- The Translational Research Institute for Neurological Disorders of Wannan Medical College, Department of Neurosurgery, the First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Degang Wu
- The Translational Research Institute for Neurological Disorders of Wannan Medical College, Department of Neurosurgery, the First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Haibin Dai
- Department of Neurosurgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
| | - Zong Zhuang
- Department of Neurosurgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, China
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Chu D, Li X, Qu X, Diwan D, Warner DS, Zipfel GJ, Sheng H. SIRT1 Activation Promotes Long-Term Functional Recovery After Subarachnoid Hemorrhage in Rats. Neurocrit Care 2023; 38:622-632. [PMID: 36224490 DOI: 10.1007/s12028-022-01614-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 09/19/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND An increase in sirtuin 1 (SIRT1) reportedly attenuates early brain injury, delayed cerebral ischemia, and short-term neurologic deficits in rodent models of subarachnoid hemorrhage (SAH). This study investigates the effect of resveratrol, a SIRT1 activator, on long-term functional recovery in a clinically relevant rat model of SAH. METHODS Thirty male Wistar rats were subjected to fresh arterial blood injection into the prechiasmatic space and randomized to receive 7 days of intraperitoneal resveratrol (20 mg/kg) or vehicle injections. Body weight and rotarod performance were measured on days 0, 3, 7, and 34 post SAH. The neurologic score was assessed 7 and 34 days post SAH. Morris water maze performance was evaluated 29-33 days post SAH. Brain SIRT1 activity and CA1 neuronal survival were also assessed. RESULTS Blood pressure rapidly increased in all SAH rats, and no between-group differences in blood pressure, blood gases, or glucose were detected. SAH induced weight loss during the first 7 days, which gradually recovered in both groups. Neurologic score and rotarod performance were significantly improved after resveratrol treatment at 34 days post SAH (p = 0.01 and 0.04, respectively). Latency to find the Morris water maze hidden platform was shortened (p = 0.02). In the resveratrol group, more CA1 neurons survived following SAH (p = 0.1). An increase in brain SIRT1 activity was confirmed in the resveratrol group (p < 0.05). CONCLUSIONS Treatment with resveratrol for 1 week significantly improved the neurologic score, rotarod performance, and latency to find the Morris water maze hidden platform 34 days post SAH. These findings indicate that SIRT1 activation warrants further investigation as a mechanistic target for SAH therapy.
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Affiliation(s)
- Dongmei Chu
- Multidisciplinary Neuroprotection Laboratories, Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Box 3094, Durham, NC, 27710, USA
- Department of Pediatrics, The Fifth Central Hospital of Tianjin, Tanggu District, Tianjin, China
| | - Xuan Li
- Multidisciplinary Neuroprotection Laboratories, Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Box 3094, Durham, NC, 27710, USA
- Department of Anesthesiology, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
| | - Xingguang Qu
- Multidisciplinary Neuroprotection Laboratories, Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Box 3094, Durham, NC, 27710, USA
- Intensive Care Unit, The First College of Clinical Medical Sciences, China Three Gorges University, Yichang, Hubei, China
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - David S Warner
- Multidisciplinary Neuroprotection Laboratories, Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Box 3094, Durham, NC, 27710, USA
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Huaxin Sheng
- Multidisciplinary Neuroprotection Laboratories, Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University Medical Center, Box 3094, Durham, NC, 27710, USA.
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Batiha GES, Al-kuraishy HM, Al-Gareeb AI, Elekhnawy E. SIRT1 pathway in Parkinson's disease: a faraway snapshot but so close. Inflammopharmacology 2023; 31:37-56. [PMID: 36580159 PMCID: PMC9957916 DOI: 10.1007/s10787-022-01125-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Accepted: 12/19/2022] [Indexed: 12/30/2022]
Abstract
Silent information regulator (SIRT) has distinctive enzymatic activities and physiological functions to control cell-cycle progression, gene expression, and DNA stability by targeting histone and non-histone proteins. SIRT1 enhances synaptic formation and synaptic activity, and therefore, can reduce the progression of various degenerative brain diseases including Parkinson's disease (PD). SIRT1 activity is decreased by aging with a subsequent increased risk for the development of degenerative brain diseases. Inhibition of SIRT1 promotes inflammatory reactions since SIRT1 inhibits transcription of nuclear factor kappa B (NF-κB) which also inhibits SIRT1 activation via activation of microRNA and miR-34a which reduce NAD synthesis. SIRT1 is highly expressed in microglia as well as neurons, and has antioxidant and anti-inflammatory effects. Therefore, this review aimed to find the possible role of SIRT1 in PD neuropathology. SIRT1 has neuroprotective effects; therefore, downregulation of SIRT1 during aging promotes p53 expression and may increase the vulnerability of neuronal cell deaths. PD neuropathology is linked with the sequence of inflammatory changes and the release of pro-inflammatory cytokines due to the activation of inflammatory signaling pathways. In addition, oxidative stress, inflammatory disorders, mitochondrial dysfunction, and apoptosis contribute mutually to PD neuropathology. Thus, SIRT1 and SIRT1 activators play a crucial role in the mitigation of PD neuropathology through the amelioration of oxidative stress, inflammatory disorders, mitochondrial dysfunction, apoptosis, and inflammatory signaling pathways.
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Affiliation(s)
- Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhour University, Damanhour, 22511 AlBeheira Egypt
| | - Hayder M. Al-kuraishy
- Department of Pharmacology, Toxicology and Medicine, College of Medicine, Al-Mustansiriyah University, Baghdad, 14132 Iraq
| | - Ali I. Al-Gareeb
- Department of Pharmacology, Toxicology and Medicine, College of Medicine, Al-Mustansiriyah University, Baghdad, 14132 Iraq
| | - Engy Elekhnawy
- Pharmaceutical Microbiology Department, Faculty of Pharmacy, Tanta University, Tanta, 31527 Egypt
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Jin J, Duan J, Du L, Xing W, Peng X, Zhao Q. Inflammation and immune cell abnormalities in intracranial aneurysm subarachnoid hemorrhage (SAH): Relevant signaling pathways and therapeutic strategies. Front Immunol 2022; 13:1027756. [PMID: 36505409 PMCID: PMC9727248 DOI: 10.3389/fimmu.2022.1027756] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/31/2022] [Indexed: 11/25/2022] Open
Abstract
Intracranial aneurysm subarachnoid hemorrhage (SAH) is a cerebrovascular disorder associated with high overall mortality. Currently, the underlying mechanisms of pathological reaction after aneurysm rupture are still unclear, especially in the immune microenvironment, inflammation, and relevant signaling pathways. SAH-induced immune cell population alteration, immune inflammatory signaling pathway activation, and active substance generation are associated with pro-inflammatory cytokines, immunosuppression, and brain injury. Crosstalk between immune disorders and hyperactivation of inflammatory signals aggravated the devastating consequences of brain injury and cerebral vasospasm and increased the risk of infection. In this review, we discussed the role of inflammation and immune cell responses in the occurrence and development of aneurysm SAH, as well as the most relevant immune inflammatory signaling pathways [PI3K/Akt, extracellular signal-regulated kinase (ERK), hypoxia-inducible factor-1α (HIF-1α), STAT, SIRT, mammalian target of rapamycin (mTOR), NLRP3, TLR4/nuclear factor-κB (NF-κB), and Keap1/nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/ARE cascades] and biomarkers in aneurysm SAH. In addition, we also summarized potential therapeutic drugs targeting the aneurysm SAH immune inflammatory responses, such as nimodipine, dexmedetomidine (DEX), fingolimod, and genomic variation-related aneurysm prophylactic agent sunitinib. The intervention of immune inflammatory responses and immune microenvironment significantly reduces the secondary brain injury, thereby improving the prognosis of patients admitted to SAH. Future studies should focus on exploring potential immune inflammatory mechanisms and developing additional therapeutic strategies for precise aneurysm SAH immune inflammatory regulation and genomic variants associated with aneurysm formation.
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Affiliation(s)
- Jing Jin
- Department of Pharmacy, West China Hospital, Sichuan University, Chengdu, Sichuan, China,Department of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jian Duan
- Department of Cerebrovascular Disease, Suining Central Hospital, Suining, Sichuan, China
| | - Leiya Du
- 4Department of Oncology, The Second People Hospital of Yibin, Yibin, Sichuan, China
| | - Wenli Xing
- Department of Cerebrovascular Disease, Suining Central Hospital, Suining, Sichuan, China
| | - Xingchen Peng
- Department of Biotherapy, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China,*Correspondence: Qijie Zhao, ; Xingchen Peng,
| | - Qijie Zhao
- Department of Pharmacy, West China Hospital, Sichuan University, Chengdu, Sichuan, China,*Correspondence: Qijie Zhao, ; Xingchen Peng,
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Zeng Y, Fang Z, Lai J, Wu Z, Lin W, Yao H, Hu W, Chen J, Guo X, Chen X. Activation of Sirtuin-1 by Pinocembrin Treatment Contributes to Reduced Early Brain Injury after Subarachnoid Hemorrhage. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:2242833. [PMID: 36439686 PMCID: PMC9683949 DOI: 10.1155/2022/2242833] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/05/2022] [Accepted: 09/09/2022] [Indexed: 10/03/2023]
Abstract
Subarachnoid hemorrhage (SAH) as a devastating neurological disorder is closely related to heightened oxidative insults and neuroinflammatory injury. Pinocembrin, a bioflavonoid, exhibits different biological functions, such as immunomodulatory, anti-inflammatory, antioxidative, and cerebroprotective activities. Herein, we examined the protective effects and molecular mechanisms of pinocembrin in a murine model of SAH. Using an endovascular perforation model in rats, pinocembrin significantly mitigated SAH-induced neuronal tissue damage, including inflammatory injury and free-radical insults. Meanwhile, pinocembrin improved behavior function and reduced neuronal apoptosis. We also revealed that sirtuin-1 (SIRT1) activation was significantly enhanced by pinocembrin. In addition, pinocembrin treatment evidently enhanced peroxisome proliferator-activated receptor-γ coactivator expression and suppressed ac-nuclear factor-kappa B levels. In contrast, EX-527, a selective SIRT1 inhibitor, blunted the protective effects of pinocembrin against SAH by suppressing SIRT1-mediated signaling. These results suggested that the cerebroprotective actions of pinocembrin after SAH were through SIRT1-dependent pathway, suggesting the potential application of pinocembrin for the treatment of SAH.
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Affiliation(s)
- Yile Zeng
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Zhongning Fang
- Department of Neurosurgery, The Jinjiang Municipal Hospital, Quanzhou, Fujian, China
| | - Jinqing Lai
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
- Centre of Neurological and Metabolic Research, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Zhe Wu
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
- Centre of Neurological and Metabolic Research, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Weibin Lin
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Hao Yao
- Department of Neurosurgery, The Jinjiang Municipal Hospital, Quanzhou, Fujian, China
| | - Weipeng Hu
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Junyan Chen
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
| | - Xieli Guo
- Department of Neurosurgery, The Jinjiang Municipal Hospital, Quanzhou, Fujian, China
| | - Xiangrong Chen
- Department of Neurosurgery, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
- Centre of Neurological and Metabolic Research, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, China
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Clarke JV, Brier LM, Rahn RM, Diwan D, Yuan JY, Bice AR, Imai SI, Vellimana AK, Culver JP, Zipfel GJ. SIRT1 mediates hypoxic postconditioning- and resveratrol-induced protection against functional connectivity deficits after subarachnoid hemorrhage. J Cereb Blood Flow Metab 2022; 42:1210-1223. [PMID: 35137611 PMCID: PMC9207494 DOI: 10.1177/0271678x221079902] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Functional connectivity (FC) is a sensitive metric that provides a readout of whole cortex coordinate neural activity in a mouse model. We examine the impact of experimental SAH modeled through endovascular perforation, and the effectiveness of subsequent treatment on FC, through three key questions: 1) Does the endovascular perforation model of SAH induce deficits in FC; 2) Does exposure to hypoxic conditioning provide protection against these FC deficits and, if so, is this neurovascular protection SIRT1-mediated; and 3) does treatment with the SIRT1 activator resveratrol alone provide protection against these FC deficits? Cranial windows were adhered on skull-intact mice that were then subjected to either sham or SAH surgery and either left untreated or treated with hypoxic post-conditioning (with or without EX527) or resveratrol for 3 days. Mice were imaged 3 days post-SAH/sham surgery, temporally aligned with the onset of major SAH sequela in mice. Here we show that the endovascular perforation model of SAH induces global and network-specific deficits in FC by day 3, corresponding with the time frame of DCI in mice. Hypoxic conditioning provides SIRT1-mediated protection against these network-specific FC deficits post-SAH, as does treatment with resveratrol. Conditioning-based strategies provide multifaceted neurovascular protection in experimental SAH.
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Affiliation(s)
- Julian V Clarke
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Lindsey M Brier
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Rachel M Rahn
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Jane Y Yuan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Annie R Bice
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Shin-Ichiro Imai
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Joseph P Culver
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
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10
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Cycloastragenol Confers Cerebral Protection after Subarachnoid Hemorrhage by Suppressing Oxidative Insults and Neuroinflammation via the SIRT1 Signaling Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:3099409. [PMID: 35693703 PMCID: PMC9184193 DOI: 10.1155/2022/3099409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 04/21/2022] [Accepted: 05/03/2022] [Indexed: 12/04/2022]
Abstract
Subarachnoid hemorrhage (SAH) is an acute cerebral vascular disease featured by oxidative insults and neuroinflammation. Cycloastragenol (CAG), the major active component of Astragalus radix, has a wide range of biological functions. However, the potential beneficial effects and the underlying molecular mechanisms of CAG on SAH remain obscure. In the current study, the cerebroprotective effects and mechanism of CAG on SAH were evaluated both in vivo and in vitro. Our results indicated that CAG significantly suppressed SAH-triggered oxidative insults, inflammatory mediators production, microglia activation, and the neutrophil infiltration in the brain. In addition, CAG improved neurological function and ameliorated neuronal apoptosis and degeneration after SAH. In vitro results also revealed the therapeutic effects of CAG on neurons and microglia co-culture system. Mechanistically, CAG treatment upregulated sirtuin 1 (SIRT1) expression, inhibited the levels of FoxO1, nuclear factor-kappa B, and p53 acetylation, and suppressed the subsequent oxidative, inflammatory, and apoptotic pathways. In contrast, inhibiting SIRT1 by pretreatment with Ex527 abrogated the protective actions of CAG both in vivo and in vitro models of SAH. Collectively, our findings indicated that CAG could be a promising and effective drug candidate for SAH.
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Xia DY, Yuan JL, Jiang XC, Qi M, Lai NS, Wu LY, Zhang XS. SIRT1 Promotes M2 Microglia Polarization via Reducing ROS-Mediated NLRP3 Inflammasome Signaling After Subarachnoid Hemorrhage. Front Immunol 2021; 12:770744. [PMID: 34899720 PMCID: PMC8653696 DOI: 10.3389/fimmu.2021.770744] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 10/28/2021] [Indexed: 11/23/2022] Open
Abstract
Mounting evidence has suggested that modulating microglia polarization from pro-inflammatory M1 phenotype to anti-inflammatory M2 state might be a potential therapeutic approach in the treatment of subarachnoid hemorrhage (SAH) injury. Our previous study has indicated that sirtuin 1 (SIRT1) could ameliorate early brain injury (EBI) in SAH by reducing oxidative damage and neuroinflammation. However, the effects of SIRT1 on microglial polarization and the underlying molecular mechanisms after SAH have not been fully illustrated. In the present study, we first observed that EX527, a potent selective SIRT1 inhibitor, enhanced microglial M1 polarization and nod-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation in microglia after SAH. Administration of SRT1720, an agonist of SIRT1, significantly enhanced SIRT1 expression, improved functional recovery, and ameliorated brain edema and neuronal death after SAH. Moreover, SRT1720 modulated the microglia polarization shift from the M1 phenotype and skewed toward the M2 phenotype. Additionally, SRT1720 significantly decreased acetylation of forkhead box protein O1, inhibited the overproduction of reactive oxygen species (ROS) and suppressed NLRP3 inflammasome signaling. In contrast, EX527 abated the upregulation of SIRT1 and reversed the inhibitory effects of SRT1720 on ROS-NLRP3 inflammasome activation and EBI. Similarly, in vitro, SRT1720 suppressed inflammatory response, oxidative damage, and neuronal degeneration, and improved cell viability in neurons and microglia co-culture system. These effects were associated with the suppression of ROS-NLRP3 inflammasome and stimulation of SIRT1 signaling, which could be abated by EX527. Altogether, these findings indicate that SRT1720, an SIRT1 agonist, can ameliorate EBI after SAH by shifting the microglial phenotype toward M2 via modulation of ROS-mediated NLRP3 inflammasome signaling.
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Affiliation(s)
- Da-Yong Xia
- Department of Neurosurgery, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Jin-Long Yuan
- Department of Neurosurgery, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Xiao-Chun Jiang
- Department of Neurosurgery, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Min Qi
- Department of Neurosurgery, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Nian-Sheng Lai
- Department of Neurosurgery, The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College), Wuhu, China
| | - Ling-Yun Wu
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Xiang-Sheng Zhang
- Department of Neurosurgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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12
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Zhang XS, Lu Y, Li W, Tao T, Wang WH, Gao S, Zhou Y, Guo YT, Liu C, Zhuang Z, Hang CH, Li W. Cerebroprotection by dioscin after experimental subarachnoid haemorrhage via inhibiting NLRP3 inflammasome through SIRT1-dependent pathway. Br J Pharmacol 2021; 178:3648-3666. [PMID: 33904167 DOI: 10.1111/bph.15507] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND AND PURPOSE Dioscin has multiple biological activities and is beneficial for cardiovascular and cerebral vascular diseases. Here, we investigated the protective effects of dioscin against subarachnoid haemorrhage and the molecular mechanisms involved. EXPERIMENTAL APPROACH Dioscin was administered after subarachnoid haemorrhage induced in rats. MCC950, a potent selective nod-like receptor pyrin domain-containing 3 (NLRP3) inhibitor, was used to suppress NLRP3 and EX527 (selisistat) was used to inhibit sirtuin 1 (SIRT1). KEY RESULTS In vivo, dioscin inhibited acute inflammatory response, oxidative damage, neurological impairment and neural cell degeneration after subarachnoid haemorrhage along with dramatically suppressing NLRP3 inflammasome activation. While pretreatment with MCC950 reduced the inflammatory response and improved neurological outcomes it did not lessen ROS production. However, giving dioscin after MCC950 reduced acute brain damage and ROS production. Dioscin increased SIRT1 expression after subarachnoid haemorrhage, whereas EX527 abolished the up-regulation of SIRT1 induced by dioscin and offset the inhibitory effects of dioscin on NLRP3 inflammasome activation. EX527 pretreatment also reversed the neuroprotective effects of dioscin against subarachnoid haemorrhage. Similarly, in vitro, dioscin dose-dependently suppressed inflammatory response, oxidative damage and neuronal degeneration and improved cell viability in neurons and microglia co-culture system. These effects were associated with inhibition of the NLRP3 inflammasome and stimulation of SIRT1 signalling, which could be inhibited by EX527 pretreatment. CONCLUSION AND IMPLICATIONS Dioscin provides protection against subarachnoid haemorrhage via the suppression of NLRP3 inflammasome activation through SIRT1-dependent pathway. Dioscin may be a new candidate to ameliorate early brain injury after subarachnoid haemorrhage.
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Affiliation(s)
- Xiang-Sheng Zhang
- Department of Neurosurgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China.,Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yue Lu
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Wen Li
- Department of Pharmacy, Beijing Boai Hospital, China Rehabilitation Research Center, Capital Medical University, Beijing, China
| | - Tao Tao
- Department of Neurosurgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, China
| | - Wei-Han Wang
- Department of Neurosurgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Sen Gao
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yan Zhou
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Yi-Ting Guo
- Department of Neurosurgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Cang Liu
- Department of Neurosurgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Zong Zhuang
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Chun-Hua Hang
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Wei Li
- Department of Neurosurgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
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13
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Role of SIRT1 in Isoflurane Conditioning-Induced Neurovascular Protection against Delayed Cerebral Ischemia Secondary to Subarachnoid Hemorrhage. Int J Mol Sci 2021; 22:ijms22084291. [PMID: 33924243 PMCID: PMC8074752 DOI: 10.3390/ijms22084291] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 04/16/2021] [Accepted: 04/17/2021] [Indexed: 12/19/2022] Open
Abstract
We recently reported that isoflurane conditioning provided multifaceted protection against subarachnoid hemorrhage (SAH)-induced delayed cerebral ischemia (DCI), and this protection was through the upregulation of endothelial nitric oxide synthase (eNOS). SIRT1, an NAD-dependent deacetylase, was shown to be one of the critical regulators of eNOS. The aim of our current study is to examine the role of SIRT1 in isoflurane conditioning-induced neurovascular protection against SAH-induced DCI. Mice were divided into four groups: sham, SAH, or SAH with isoflurane conditioning (with and without EX-527). Experimental SAH via endovascular perforation was performed. Anesthetic conditioning was performed with isoflurane 2% for 1 h, 1 h after SAH. EX-527, a selective SIRT1 inhibitor, 10 mg/kg was injected intraperitoneally immediately after SAH in the EX-527 group. SIRT1 mRNA expression and activity levels were measured. Vasospasm, microvessel thrombosis, and neurological outcome were assessed. SIRT1 mRNA expression was downregulated, and no difference in SIRT1 activity was noted after isoflurane exposure. Isoflurane conditioning with and without EX-527 attenuated vasospasm, microvessel thrombosis and improved neurological outcomes. Our data validate our previous findings that isoflurane conditioning provides strong protection against both the macro and micro vascular deficits induced by SAH, but this protection is likely not mediated through the SIRT1 pathway.
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14
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Han Y, Tong Z, Wang C, Li X, Liang G. Oleanolic acid exerts neuroprotective effects in subarachnoid hemorrhage rats through SIRT1-mediated HMGB1 deacetylation. Eur J Pharmacol 2021; 893:173811. [PMID: 33345851 DOI: 10.1016/j.ejphar.2020.173811] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 12/09/2020] [Accepted: 12/11/2020] [Indexed: 02/07/2023]
Abstract
Anti-inflammatory therapy for early brain injury after subarachnoid hemorrhage is a promising treatment for improving the prognosis. HMGB1 is the initiator of early inflammation after subarachnoid hemorrhage. Oleanolic acid is a natural pentacyclic triterpenoid compound with strong anti-inflammatory activity. It can relieve early brain injury in subarachnoid hemorrhage rats, but its mechanism is not very clear. Here, we study the potential mechanism of Oleanolic acid in the treatment of subarachnoid hemorrhage. First, we demonstrated that oleanolic acid alleviated early brain injury after subarachnoid hemorrhage, including improvement of grading score, neurological score, brain edema and permeability of brain blood barrier. Then we found that oleanolic acid could inhibit the transfer of HMGB1 from nucleus to cytoplasm and reduce the level of serum HMGB1. Furthermore, we found that oleanolic acid decreased the acetylation level of HMGB1 by increasing SIRT1 expression rather than by inhibiting JAK/STAT3 pathway. SIRT1 inhibitor sirtinol eliminated all beneficial effects of oleanolic acid on subarachnoid hemorrhage, which indicated that oleanolic acid inhibited the acetylation of HMGB1 by up regulating SIRT1. In addition, oleanolic acid treatment also reduced the levels of TLR4 and apoptosis related factors and reduced neuronal apoptosis after subarachnoid hemorrhage. In summary, our findings suggest that oleanolic acid may activate SIRT1 by acting as an activator of SIRT1, thereby reducing the acetylation of HMGB1, thus playing an anti-inflammatory role to alleviate early brain injury after subarachnoid hemorrhage.
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Affiliation(s)
- Yuwei Han
- Department of Neurosurgery, General Hospital of Northern Theater Command, Shenyang, China; China Medical University, Shenyang, China
| | - Zhenhua Tong
- Department of Science Training, General Hospital of Northern Theater Command, Shenyang, China
| | - Chenchen Wang
- Department of Neurosurgery, General Hospital of Northern Theater Command, Shenyang, China
| | - Xiaoming Li
- Department of Neurosurgery, General Hospital of Northern Theater Command, Shenyang, China.
| | - Guobiao Liang
- Department of Neurosurgery, General Hospital of Northern Theater Command, Shenyang, China.
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15
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Vellimana AK, Aum DJ, Diwan D, Clarke JV, Nelson JW, Lawrence M, Han BH, Gidday JM, Zipfel GJ. SIRT1 mediates hypoxic preconditioning induced attenuation of neurovascular dysfunction following subarachnoid hemorrhage. Exp Neurol 2020; 334:113484. [PMID: 33010255 DOI: 10.1016/j.expneurol.2020.113484] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/18/2020] [Accepted: 09/24/2020] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND PURPOSE Vasospasm and delayed cerebral ischemia (DCI) contribute significantly to the morbidity/mortality associated with aneurysmal subarachnoid hemorrhage (SAH). While considerable research effort has focused on preventing or reversing vasospasm, SAH-induced brain injury occurs in response to a multitude of concomitantly acting pathophysiologic mechanisms. In this regard, the pleiotropic epigenetic responses to conditioning-based therapeutics may provide an ideal SAH therapeutic strategy. We previously documented the ability of hypoxic preconditioning (PC) to attenuate vasospasm and neurological deficits after SAH, in a manner that depends on the activity of endothelial nitric oxide synthase. The present study was undertaken to elucidate whether the NAD-dependent protein deacetylase sirtuin isoform SIRT1 is an upstream mediator of hypoxic PC-induced protection, and to assess the efficacy of the SIRT1-activating polyphenol Resveratrol as a pharmacologic preconditioning therapy. METHODS Wild-type C57BL/6J mice were utilized in the study and subjected to normoxia or hypoxic PC. Surgical procedures included induction of SAH via endovascular perforation or sham surgery. Multiple endpoints were assessed including cerebral vasospasm, neurobehavioral deficits, SIRT1 expression via quantitative real-time PCR for mRNA, and western blot for protein quantification. Pharmacological agents utilized in the study include EX-527 (SIRT1 inhibitor), and Resveratrol (SIRT1 activator). RESULTS Hypoxic PC leads to rapid and sustained increase in cerebral SIRT1 mRNA and protein expression. SIRT1 inhibition blocks the protective effects of hypoxic PC on vasospasm and neurological deficits. Resveratrol pretreatment dose-dependently abrogates vasospasm and attenuates neurological deficits following SAH - beneficial effects that were similarly blocked by pharmacologic inhibition of SIRT1. CONCLUSION SIRT1 mediates hypoxic preconditioning-induced protection against neurovascular dysfunction after SAH. Resveratrol mimics this neurovascular protection, at least in part, via SIRT1. Activation of SIRT1 is a promising, novel, pleiotropic therapeutic strategy to combat DCI after SAH.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Diane J Aum
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Julian V Clarke
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - James W Nelson
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Molly Lawrence
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Byung Hee Han
- Department of Pharmacology, A.T. Still University of Health Sciences, Kirksville College of Osteopathic Medicine, Kirksville, MO 63501, USA
| | - Jeffrey M Gidday
- Departments of Ophthalmology, Physiology, Biochemistry, and Neuroscience, Louisiana State University, New Orleans, Louisiana, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA.
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