51
|
Involvement of Microglia in the Pathophysiology of Intracranial Aneurysms and Vascular Malformations-A Short Overview. Int J Mol Sci 2021; 22:ijms22116141. [PMID: 34200256 PMCID: PMC8201350 DOI: 10.3390/ijms22116141] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 12/19/2022] Open
Abstract
Aneurysms and vascular malformations of the brain represent an important source of intracranial hemorrhage and subsequent mortality and morbidity. We are only beginning to discern the involvement of microglia, the resident immune cell of the central nervous system, in these pathologies and their outcomes. Recent evidence suggests that activated proinflammatory microglia are implicated in the expansion of brain injury following subarachnoid hemorrhage (SAH) in both the acute and chronic phases, being also a main actor in vasospasm, considerably the most severe complication of SAH. On the other hand, anti-inflammatory microglia may be involved in the resolution of cerebral injury and hemorrhage. These immune cells have also been observed in high numbers in brain arteriovenous malformations (bAVM) and cerebral cavernomas (CCM), although their roles in these lesions are currently incompletely ascertained. The following review aims to shed a light on the most significant findings related to microglia and their roles in intracranial aneurysms and vascular malformations, as well as possibly establish the course for future research.
Collapse
|
52
|
Neuroprotective Strategies in Aneurysmal Subarachnoid Hemorrhage (aSAH). Int J Mol Sci 2021; 22:ijms22115442. [PMID: 34064048 PMCID: PMC8196706 DOI: 10.3390/ijms22115442] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/30/2021] [Accepted: 05/18/2021] [Indexed: 12/19/2022] Open
Abstract
Aneurysmal subarachnoid hemorrhage (aSAH) remains a disease with high mortality and morbidity. Since treating vasospasm has not inevitably led to an improvement in outcome, the actual emphasis is on finding neuroprotective therapies in the early phase following aSAH to prevent secondary brain injury in the later phase of disease. Within the early phase, neuroinflammation, thromboinflammation, disturbances in brain metabolism and early neuroprotective therapies directed against delayed cerebral ischemia (DCI) came into focus. Herein, the role of neuroinflammation, thromboinflammation and metabolism in aSAH is depicted. Potential neuroprotective strategies regarding neuroinflammation target microglia activation, metalloproteases, autophagy and the pathway via Toll-like receptor 4 (TLR4), high mobility group box 1 (HMGB1), NF-κB and finally the release of cytokines like TNFα or IL-1. Following the link to thromboinflammation, potential neuroprotective therapies try to target microthrombus formation, platelets and platelet receptors as well as clot clearance and immune cell infiltration. Potential neuroprotective strategies regarding metabolism try to re-balance the mismatch of energy need and supply following aSAH, for example, in restoring fuel to the TCA cycle or bypassing distinct energy pathways. Overall, this review addresses current neuroprotective strategies in aSAH, hopefully leading to future translational therapy options to prevent secondary brain injury.
Collapse
|
53
|
Sun XG, Zhang MM, Liu SY, Chu XH, Xue GQ, Zhang BC, Zhu JB, Godje Godje IS, Zhu LJ, Hu HY, Hai-Wang, Shen YJ, Wang GQ. Role of TREM-1 in the development of early brain injury after subarachnoid hemorrhage. Exp Neurol 2021; 341:113692. [PMID: 33727099 DOI: 10.1016/j.expneurol.2021.113692] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 02/23/2021] [Accepted: 03/11/2021] [Indexed: 12/12/2022]
Abstract
Triggering receptor expressed on myeloid cells-1 (TREM-1) was found to be induced in the context of subarachnoid hemorrhage (SAH) before. This study further investigates its role in the development of SAH-induced early brain injury (EBI). Firstly, rats were randomly divided into Sham and SAH groups for analysis of temporal patterns and cellular localization of TREM-1. Secondly, TREM-1 intervention was administrated to produce Sham, vehicle, antagonist and agonist groups, for analyzing TREM-1, Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and NF-κB expressions at 24 h post-modeling, and EBI assessment at 24 h and 72 h. Thirdly, TLR4 inhibitor (TAK-242) was exploited to produce Sham, Sham+TAK-242, SAH, and SAH + TAK-242 groups to analyze the effects of TLR4 inhibition on TREM-1 induction and EBI evaluation at 72 h. Fourthly, the relationship of soluble TREM-1 (sTREM-1) levels in cerebrospinal fluid of SAH patients with Hunt-Hess grades were explored. The results showed that TREM-1 increased in the brain after experimental SAH (eSAH) early at 6 h and peaked at 48 h, which was found to be located in microglia and endothelial cells. TREM-1 inhibition attenuated EBI associated with TLR4/MyD88/NF-κB suppression, while enhancement had the opposite effects. Contrarily, TLR4 inhibition prevented TREM-1 induction and ameliorated EBI. In addition, sTREM-1 levels in SAH patients positively correlated with Hunt-Hess grades. Overall, the present study provides new evidence that TREM-1 increases dynamically in the brain after eSAH and it is located in microglia and endothelial cells, which may aggravate EBI by interacting with TLR4 pathway. And sTREM-1 in patients might act as a monitoring biomarker of EBI, providing new insights for future studies.
Collapse
Affiliation(s)
- Xin-Gang Sun
- Department of Neurology, the Second Hospital Affiliated to Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China.
| | - Mi-Mi Zhang
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Shao-Yu Liu
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Xue-Hong Chu
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Guo-Qiang Xue
- Department of Neurosurgery, Yuncheng Hospital Affiliated to Shanxi Medical University, Yuncheng, Shanxi 044000, People's Republic of China
| | - Bao-Chen Zhang
- Department of Neurosurgery, Yuncheng Hospital Affiliated to Shanxi Medical University, Yuncheng, Shanxi 044000, People's Republic of China
| | - Jia-Bao Zhu
- Department of Neurosurgery, Yuncheng Hospital Affiliated to Shanxi Medical University, Yuncheng, Shanxi 044000, People's Republic of China
| | | | - Li-Juan Zhu
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Hui-Yu Hu
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Hai-Wang
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Ying-Jie Shen
- Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| | - Gai-Qing Wang
- Department of Neurology, the Second Hospital Affiliated to Shanxi Medical University, Taiyuan, Shanxi 030000, People's Republic of China
| |
Collapse
|
54
|
Barpujari A, Patel C, Zelmonovich R, Clark A, Patel D, Pierre K, Scott K, Lucke Wold B. Pharmaceutical Management for Subarachnoid Hemorrhage. RECENT TRENDS IN PHARMACEUTICAL SCIENCES AND RESEARCH 2021; 3:16-30. [PMID: 34984419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 09/28/2022]
Abstract
Aneurysmal subarachnoid hemorrhage can have deleterious consequences. Vasospasm, delayed cerebral ischemia, and re-hemorrhage can all cause delayed sequelae. Furthermore, severe headaches are common and require careful modulation of pain medications. Limited treatment options currently exist and are becoming more complex with the rising use of oral anticoagulants needing reversal. In this review, we highlight the current treatment options currently employed and address avenues of future discovery based on emerging preclinical data. Furthermore, we dive into the best treatment approach for managing headaches following subarachnoid hemorrhage. The review is designed to serve as a catalyst for further prospective investigation into this important topic.
Collapse
Affiliation(s)
- Arnav Barpujari
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | - Chhaya Patel
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | | | - Alec Clark
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | - Devan Patel
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | - Kevin Pierre
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | - Kyle Scott
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | | |
Collapse
|