Background: It is reported that the expression of aquaporin4 (AQP4) in the brain is increased and leads to the brain edema after subarachnoid hemorrhage (SAH). In this study, by using AQP4 knockout rat model, the opposite role of AQP4 in early brain injury following SAH through modulation of interstitial fluid (ISF) transportation in the brain glymphatic system had been explored.
Methods: The SAH model was established using endovascular perforation method, the AQP4 knockout rat model was generated using TALENs (transcription activator-like (TAL) effector nucleases) technique. The animals were randomly divided into four groups: sham (n = 16), AQP4−/−sham (n = 16), SAH (n = 24), and AQP4−/−SAH groups (n = 27). The roles of AQP4 in the brain water content and neurological function were detected. In addition, immunohistochemistry and Nissl staining were applied to observe the effects of AQP4 on the blood–brain barrier (BBB) integrity and the loss of neurons in the hippocampus. To explore the potential mechanism of these effects, the distribution of Gd-DTPA (interstitial fluid indicator) injected from cisterna magna was evaluated with MRI.
Results: Following SAH, AQP4 knockout could significantly increase the water content in the whole brain and aggravate the neurological deficits. Furthermore, the loss of neuron and BBB disruption in hippocampus were also exacerbated. The MRI results indicated that the ISF transportation in the glymphatic system of AQP4 deficit rat was significantly injured.
Conclusion: AQP4 facilitates the ISF transportation in the brain to eliminate the toxic factors; AQP4 knockout will aggravate the early brain injury following SAH through impairment of the glymphatic system.
Aquaporin4 Early brain injury Subarachnoid hemorrhage Glymphatic system Rat
This is a preview of subscription content, log in to check access.
This work was supported by the National Natural Science Foundation of China (Grant No. 31471028) and the interdisciplinary medicine Seed Fund of Peking University (Grant No. BMU2018MC001).
Conflict of Interest: The authors declare that they have no conflict of interest.
Li J, Chen J, Mo H, Chen J, Qian C, Yan F, Gu C, Hu Q, Wang L, Chen G. Minocycline protects against NLRP3 inflammasome-induced inflammation and P53-associated apoptosis in early brain injury after subarachnoid hemorrhage. Mol Neurobiol. 2016;53:2668–78.CrossRefGoogle Scholar
Yuan J, Liu W, Zhu H, Zhang X, Feng Y, Chen Y, Feng H, Lin J. Curcumin attenuates blood-brain barrier disruption after subarachnoid hemorrhage in mice. J Surg Res. 2017;207:85–91.CrossRefGoogle Scholar
Plog BA, Nedergaard M. The glymphatic system in central nervous system health and disease: past, present, and future. Annu Rev Pathol. 2018;13:379–94.CrossRefGoogle Scholar
Jessen NA, Munk AS, Lundgaard I, Nedergaard M. The glymphatic system: a beginner’s guide. Neurochem Res. 2015;40:2583–99.CrossRefGoogle Scholar
Badaut J, Brunet JF, Grollimund L, Hamou MF, Magistretti PJ, Villemure JG, Regli L. Aquaporin 1 and aquaporin 4 expression in human brain after subarachnoid hemorrhage and in peritumoral tissue. Acta Neurochir Suppl. 2003;86:495–8.PubMedGoogle Scholar
Yang X, Chen C, Hu Q, Yan J, Zhou C. Gamma-secretase inhibitor (GSI1) attenuates morphological cerebral vasospasm in 24h after experimental subarachnoid hemorrhage in rats. Neurosci Lett. 2010;469:385–90.CrossRefGoogle Scholar
Yan JH, Khatibi NH, Han HB, Hu Q, Chen CH, Li L, Yang XM, Zhou CM. p53-induced uncoupling expression of aquaporin-4 and inwardly rectifying K+ 4.1 channels in cytotoxic edema after subarachnoid hemorrhage. CNS Neurosci Ther. 2012;18:334–42.CrossRefGoogle Scholar
Tesson L, Usal C, Menoret S, Leung E, Niles BJ, Remy S, Santiago Y, Vincent AI, Meng X, Zhang L, Gregory PD, Anegon I, Cost GJ. Knockout rats generated by embryo microinjection of TALENs. Nat Biotechnol. 2011;29:695–6.CrossRefGoogle Scholar
Sung YH, Jin Y, Kim S, Lee HW. Generation of knockout mice using engineered nucleases. Methods. 2014;69:85–93.CrossRefGoogle Scholar
Duris K, Manaenko A, Suzuki H, Rolland W, Tang J, Zhang JH. Sampling of CSF via the cisterna magna and blood collection via the heart affects brain water content in a rat SAH model. Transl Stroke Res. 2011;2:232–7.CrossRefGoogle Scholar
Garcia JH, Wagner S, Liu KF, Hu XJ. Neurological deficit and extent of neuronal necrosis attributable to middle cerebral artery occlusion in rats. Statistical validation. Stroke. 1995;26:627–34. discussion 635.CrossRefGoogle Scholar
Gaberel T, Gakuba C, Goulay R, Martinez De Lizarrondo S, Hanouz JL, Emery E, Touze E, Vivien D, Gauberti M. Impaired glymphatic perfusion after strokes revealed by contrast-enhanced MRI: a new target for fibrinolysis? Stroke. 2014;45:3092–6.CrossRefGoogle Scholar
Zhou C, Yamaguchi M, Colohan AR, Zhang JH. Role of p53 and apoptosis in cerebral vasospasm after experimental subarachnoid hemorrhage. J Cereb Blood Flow Metab. 2005;25:572–82.CrossRefGoogle Scholar
Sehba FA, Hou J, Pluta RM, Zhang JH. The importance of early brain injury after subarachnoid hemorrhage. Prog Neurobiol. 2012;97:14–37.CrossRefGoogle Scholar
Fujii M, Yan J, Rolland WB, Soejima Y, Caner B, Zhang JH. Early brain injury, an evolving frontier in subarachnoid hemorrhage research. Transl Stroke Res. 2013;4:432–46.CrossRefGoogle Scholar
Goulay R, Flament J, Gauberti M, Naveau M, Pasquet N, Gakuba C, Emery E, Hantraye P, Vivien D, Aron-Badin R, Gaberel T. Subarachnoid hemorrhage severely impairs brain parenchymal cerebrospinal fluid circulation in nonhuman primate. Stroke. 2017;48:2301–5.CrossRefGoogle Scholar
Luo C, Yao X, Li J, He B, Liu Q, Ren H, Liang F, Li M, Lin H, Peng J, Yuan TF, Pei Z, Su H. Paravascular pathways contribute to vasculitis and neuroinflammation after subarachnoid hemorrhage independently of glymphatic control. Cell Death Dis. 2016;7:e2160.CrossRefGoogle Scholar
Morris AW, Sharp MM, Albargothy NJ, Fernandes R, Hawkes CA, Verma A, Weller RO, Carare RO. Vascular basement membranes as pathways for the passage of fluid into and out of the brain. Acta Neuropathol. 2016;131:725–36.CrossRefGoogle Scholar
Aspelund A, Antila S, Proulx ST, Karlsen TV, Karaman S, Detmar M, Wiig H, Alitalo K. A dural lymphatic vascular system that drains brain interstitial fluid and macromolecules. J Exp Med. 2015;212:991–9.CrossRefGoogle Scholar
Mestre H, Kostrikov S, Mehta RI, Nedergaard M. Perivascular spaces, glymphatic dysfunction, and small vessel disease. Clin Sci (Lond). 2017;131:2257–74.CrossRefGoogle Scholar
Peng W, Achariyar TM, Li B, Liao Y, Mestre H, Hitomi E, Regan S, Kasper T, Peng S, Ding F, Benveniste H, Nedergaard M, Deane R. Suppression of glymphatic fluid transport in a mouse model of Alzheimer’s disease. Neurobiol Dis. 2016;93:215–25.CrossRefGoogle Scholar
Arbel-Ornath M, Hudry E, Eikermann-Haerter K, Hou S, Gregory JL, Zhao L, Betensky RA, Frosch MP, Greenberg SM, Bacskai BJ. Interstitial fluid drainage is impaired in ischemic stroke and Alzheimer’s disease mouse models. Acta Neuropathol. 2013;126:353–64.CrossRefGoogle Scholar
Papadopoulos MC, Verkman AS. Aquaporin water channels in the nervous system. Nat Rev Neurosci. 2013;14:265–77.CrossRefGoogle Scholar
Vindedal GF, Thoren AE, Jensen V, Klungland A, Zhang Y, Holtzman MJ, Ottersen OP, Nagelhus EA. Removal of aquaporin-4 from glial and ependymal membranes causes brain water accumulation. Mol Cell Neurosci. 2016;77:47–52.CrossRefGoogle Scholar
Li X, Liu H, Yang Y. Magnesium sulfate attenuates brain edema by lowering AQP4 expression and inhibits glia-mediated neuroinflammation in a rodent model of eclampsia. Behav Brain Res. 2017;364:403–12.CrossRefGoogle Scholar
Han H, Shi C, Fu Y, Zuo L, Lee K, He Q, Han H. A novel MRI tracer-based method for measuring water diffusion in the extracellular space of the rat brain. IEEE J Biomed Health Inform. 2014;18:978–83.CrossRefGoogle Scholar
Nicholson C, Phillips JM. Ion diffusion modified by tortuosity and volume fraction in the extracellular microenvironment of the rat cerebellum. J Physiol. 1981;321:225–57.CrossRefGoogle Scholar
Nicholson C. Quantitative analysis of extracellular space using the method of TMA+ iontophoresis and the issue of TMA+ uptake. Can J Physiol Pharmacol. 1992;70(Suppl):S314–22.CrossRefGoogle Scholar
Xiao F, Nicholson C, Hrabe J, Hrabetova S. Diffusion of flexible random-coil dextran polymers measured in anisotropic brain extracellular space by integrative optical imaging. Biophys J. 2008;95:1382–92.CrossRefGoogle Scholar
Ten Kate M, Visser PJ, Bakardjian H, Barkhof F, Sikkes SAM, van der Flier WM, Scheltens P, Hampel H, Habert MO, Dubois B, Tijms BM. Gray matter network disruptions and regional amyloid beta in cognitively normal adults. Front Aging Neurosci. 2018;10:67.CrossRefGoogle Scholar
Blixt J, Gunnarson E, Wanecek M. Erythropoietin attenuates the brain edema response after experimental traumatic brain injury. J Neurotrauma. 2018;35:671–80.CrossRefGoogle Scholar