Abstract
Pericytes are present tight around the intervals of capillaries, play an essential role in stabilizing the blood–brain barrier, regulating blood flow and immunomodulation, and persistent contraction of pericytes eventually leads to impaired blood flow and poor clinical outcomes in ischemic stroke. We previously show that iptakalim, an ATP-sensitive potassium (K-ATP) channel opener, exerts protective effects in neurons, and glia against ischemia-induced injury. In this study we investigated the impacts of iptakalim on pericytes contraction in stroke. Mice were subjected to cerebral artery occlusion (MCAO), then administered iptakalim (10 mg/kg, ip). We showed that iptakalim administration significantly promoted recovery of cerebral blood flow after cerebral ischemia and reperfusion. Furthermore, we found that iptakalim significantly inhibited pericytes contraction, decreased the number of obstructed capillaries, and improved cerebral microcirculation. Using a collagen gel contraction assay, we demonstrated that cultured pericytes subjected to oxygen-glucose deprivation (OGD) consistently contracted from 3 h till 24 h during reoxygenation, whereas iptakalim treatment (10 μM) notably restrained pericyte contraction from 6 h during reoxygenation. We further showed that iptakalim treatment promoted K-ATP channel opening via suppressing SUR2/EPAC1 complex formation. Consequently, it reduced calcium influx and ET-1 release. Taken together, our results demonstrate that iptakalim, targeted K-ATP channels, can improve microvascular disturbance by inhibiting pericyte contraction after ischemic stroke. Our work reveals that iptakalim might be developed as a promising pericyte regulator for treatment of stroke.
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References
Kloner RA, King KS, Harrington MG. No-reflow phenomenon in the heart and brain. Am J Physiol Heart Circ Physiol. 2018;315:H550–62.
Attwell D, Mishra A, Hall CN, O’Farrell FM, Dalkara T. What is a pericyte? J Cereb Blood Flow Metab. 2016;36:451–5.
Cai W, Liu H, Zhao J, Chen LY, Chen J, Lu Z, et al. Pericytes in brain injury and repair after ischemic stroke. Transl Stroke Res. 2017;8:107–21.
Cenko E, Ricci B, Kedev S, Kalpak O, Calmac L, Vasiljevic Z, et al. The no-reflow phenomenon in the young and in the elderly. Int J Cardiol. 2016;222:1122–8.
Hossmann KA. Ischemia-mediated neuronal injury. Resuscitation. 1993;26:225–35.
Rezkalla SH, Stankowski RV, Hanna J, Kloner RA. Management of no-reflow phenomenon in the catheterization laboratory. JACC Cardiovasc Inter. 2017;10:215–23.
Dalkara T, Arsava EM. Can restoring incomplete microcirculatory reperfusion improve stroke outcome after thrombolysis? J Cereb Blood Flow Metab. 2012;32:2091–9.
Yemisci M, Gursoy-Ozdemir Y, Vural A, Can A, Topalkara K, Dalkara T. Pericyte contraction induced by oxidative-nitrative stress impairs capillary reflow despite successful opening of an occluded cerebral artery. Nat Med. 2009;15:1031–7.
Yang S, Jin H, Zhu Y, Wan Y, Opoku EN, Zhu L, et al. Diverse functions and mechanisms of pericytes in ischemic stroke. Curr Neuropharmacol. 2017;15:892–905.
Armulik A, Genove G, Betsholtz C. Pericytes: developmental, physiological, and pathological perspectives, problems, and promises. Dev Cell. 2011;21:193–215.
Pan Z, Huang J, Cui W, Long C, Zhang Y, Wang H. Targeting hypertension with a new adenosine triphosphate-sensitive potassium channel opener iptakalim. J Cardiovasc Pharmacol. 2010;56:215–28.
Sikka P, Kapoor S, Bindra VK, Saini M, Saxena KK. Iptakalim: a novel multi-utility potassium channel opener. J Pharmacol Pharmacother. 2012;3:12–4.
Ran YH, Wang H. Iptakalim, an ATP-sensitive potassium channel opener, confers neuroprotection against cerebral ischemia/reperfusion injury in rats by protecting neurovascular unit cells. J Zhejiang Univ Sci B. 2011;12:835–45.
Ji J, Yan H, Chen ZZ, Zhao Z, Yang DD, Sun XL, et al. Iptakalim protects against ischemic injury by improving neurovascular unit function in the mouse brain. Clin Exp Pharmacol Physiol. 2015;42:766–71.
Chen H, Yang Y, Yao HH, Tang XC, Ding JH, Wang H, et al. Protective effects of iptakalim, a novel ATP-sensitive potassium channel opener, on global cerebral ischemia-evoked insult in gerbils. Acta Pharmacol Sin. 2006;27:665–72.
He L, Vanlandewijck M, Mae MA, Andrae J, Ando K, Del Gaudio F, et al. Single-cell RNA sequencing of mouse brain and lung vascular and vessel-associated cell types. Sci Data. 2018;5:180160.
Lu M, Yang JZ, Geng F, Ding JH, Hu G. Iptakalim confers an antidepressant effect in a chronic mild stress model of depression through regulating neuro-inflammation and neurogenesis. Int J Neuropsychopharmacol. 2014;17:1501–10.
Tamura A, Graham DI, McCulloch J, Teasdale GM. Focal cerebral ischaemia in the rat: 1. Description of technique and early neuropathological consequences following middle cerebral artery occlusion. J Cereb Blood Flow Metab. 1981;1:53–60.
Chen RL, Nagel S, Papadakis M, Bishop T, Pollard P, Ratcliffe PJ, et al. Roles of individual prolyl-4-hydroxylase isoforms in the first 24 h following transient focal cerebral ischaemia: insights from genetically modified mice. J Physiol. 2012;590:4079–91.
Gu X, Chen W, You J, Koretsky AP, Volkow ND, Pan Y, et al. Long-term optical imaging of neurovascular coupling in mouse cortex using GCaMP6f and intrinsic hemodynamic signals. Neuroimage. 2018;165:251–64.
O’Farrell FM, Mastitskaya S, Hammond-Haley M, Freitas F, Wah WR, Attwell D. Capillary pericytes mediate coronary no-reflow after myocardial ischaemia. Elife. 2017;6:e29280. https://doi.org/10.7554/eLife.29280.
Han X, Sun S, Sun Y, Song Q, Zhu J, Song N, et al. Small molecule-driven NLRP3 inflammation inhibition via interplay between ubiquitination and autophagy: implications for Parkinson disease. Autophagy. 2019;15:1860–81.
Liu S, Connor J, Peterson S, Shuttleworth CW, Liu KJ. Direct visualization of trapped erythrocytes in rat brain after focal ischemia and reperfusion. J Cereb Blood Flow Metab. 2002;22:1222–30.
Tigges U, Welser-Alves JV, Boroujerdi A, Milner R. A novel and simple method for culturing pericytes from mouse brain. Microvasc Res. 2012;84:74–80.
Chen M, Zou W, Chen M, Cao L, Ding J, Xiao W, et al. Ginkgolide K promotes angiogenesis in a middle cerebral artery occlusion mouse model via activating JAK2/STAT3 pathway. Eur J Pharmacol. 2018;833:221–9.
Chamorro A. Neuroprotectants in the era of reperfusion therapy. J Stroke. 2018;20:197–207.
Alarcon-Martinez L, Yilmaz-Ozcan S, Yemisci M, Schallek J, Kilic K, Villafranca-Baughman D, et al. Retinal ischemia induces alpha-SMA-mediated capillary pericyte contraction coincident with perivascular glycogen depletion. Acta Neuropathol Commun. 2019;7:134.
Zhao K, Wen R, Wang X, Pei L, Yang Y, Shang Y, et al. EPAC inhibition of SUR1 receptor increases glutamate release and seizure vulnerability. J Neurosci. 2013;33:8861–5.
Bai J, Lyden PD. Revisiting cerebral postischemic reperfusion injury: new insights in understanding reperfusion failure, hemorrhage, and edema. Int J Stroke. 2015;10:143–52.
Ames A 3rd, Wright RL, Kowada M, Thurston JM, Majno G. Cerebral ischemia. II. The no-reflow phenomenon. Am J Pathol. 1968;52:437–53.
Ayata C, Lauritzen M. Spreading depression, spreading depolarizations, and the cerebral vasculature. Physiol Rev. 2015;95:953–93.
Hartings JA, Shuttleworth CW, Kirov SA, Ayata C, Hinzman JM, Foreman B, et al. The continuum of spreading depolarizations in acute cortical lesion development: examining Leao’s legacy. J Cereb Blood Flow Metab. 2017;37:1571–94.
Garcia JH, Liu KF, Yoshida Y, Chen S, Lian J. Brain microvessels: factors altering their patency after the occlusion of a middle cerebral artery (Wistar rat). Am J Pathol. 1994;145:728–40.
Granger DN, Kvietys PR. Reperfusion therapy-what’s with the obstructed, leaky and broken capillaries? Pathophysiology. 2017;24:213–28.
Mohamed Mokhtarudin MJ, Payne SJ. Mathematical model of the effect of ischemia-reperfusion on brain capillary collapse and tissue swelling. Math Biosci. 2015;263:111–20.
Fischer EG, Ames A 3d. Studies on mechanisms of impairment of cerebral circulation following ischemia: effect of hemodilution and perfusion pressure. Stroke. 1972;3:538–42.
Ritter LS, Orozco JA, Coull BM, McDonagh PF, Rosenblum WI. Leukocyte accumulation and hemodynamic changes in the cerebral microcirculation during early reperfusion after stroke. Stroke. 2000;31:1153–61.
Gould IG, Tsai P, Kleinfeld D, Linninger A. The capillary bed offers the largest hemodynamic resistance to the cortical blood supply. J Cereb Blood Flow Metab. 2017;37:52–68.
Peppiatt CM, Howarth C, Mobbs P, Attwell D. Bidirectional control of CNS capillary diameter by pericytes. Nature. 2006;443:700–4.
Nortley R, Korte N, Izquierdo P, Hirunpattarasilp C, Mishra A, Jaunmuktane Z, et al. Amyloid beta oligomers constrict human capillaries in Alzheimer’s disease via signaling to pericytes. Science. 2019;365:eaav9518.
Hossmann KA. Pathophysiology and therapy of experimental stroke. Cell Mol Neurobiol. 2006;26:1057–83.
Li Y, Lucas-Osma AM, Black S, Bandet MV, Stephens MJ, Vavrek R, et al. Pericytes impair capillary blood flow and motor function after chronic spinal cord injury. Nat Med. 2017;23:733–41.
Wang YL, Wang XH, Liu YL, Kong XQ, Wang LX. Cardiac lymphatic obstruction impairs left ventricular function and increases plasma endothelin-1 and angiotensin II in rabbits. Lymphology. 2009;42:182–7.
Grant RI, Hartmann DA, Underly RG, Berthiaume AA, Bhat NR, Shih AY. Organizational hierarchy and structural diversity of microvascular pericytes in adult mouse cortex. J Cereb Blood Flow Metab. 2019;39:411–25.
Grubb S, Cai C, Hald BO, Khennouf L, Murmu RP, Jensen AGK, et al. Precapillary sphincters maintain perfusion in the cerebral cortex. Nat Commun. 2020;11:395.
Hartmann DA, Berthiaume AA, Grant RI, Harrill SA, Koski T, Tieu T, et al. Brain capillary pericytes exert a substantial but slow influence on blood flow. Nat Neurosci. 2021;24:633–45.
Rungta RL, Chaigneau E, Osmanski BF, Charpak S. Vascular compartmentalization of functional hyperemia from the synapse to the Pia. Neuron. 2018;99:362–75.e4.
Hauck EF, Apostel S, Hoffmann JF, Heimann A, Kempski O. Capillary flow and diameter changes during reperfusion after global cerebral ischemia studied by intravital video microscopy. J Cereb Blood Flow Metab. 2004;24:383–91.
Burdyga T, Borysova L. Ca2+ signalling in pericytes. Adv Exp Med Biol. 2018;1109:95–109.
Ikebe M, Hartshorne DJ. The role of myosin phosphorylation in the contraction-relaxation cycle of smooth muscle. Experientia. 1985;41:1006–10.
Kureli G, Yilmaz-Ozcan S, Erdener SE, Donmez-Demir B, Yemisci M, Karatas H, et al. F-actin polymerization contributes to pericyte contractility in retinal capillaries. Exp Neurol. 2020;332:113392.
Wang S, Guo X, Long CL, Li C, Zhang YF, Wang J, et al. SUR2B/Kir6.1 channel openers correct endothelial dysfunction in chronic heart failure via the miR-1-3p/ET-1 pathway. Biomed Pharmacother. 2019;110:431–9.
Gao M, Wang Y, Wang H. Effects of iptakalim on intracellular calcium concentrations, PKA and PKC activities in rat tail artery smooth muscle cells. Yao Xue Xue Bao. 2005;40:954–7.
Hosford PS, Christie IN, Niranjan A, Aziz Q, Anderson N, Ang R, et al. A critical role for the ATP-sensitive potassium channel subunit KIR6.1 in the control of cerebral blood flow. J Cereb Blood Flow Metab. 2019;39:2089–95.
Kang G, Leech CA, Chepurny OG, Coetzee WA, Holz GG. Role of the cAMP sensor Epac as a determinant of KATP channel ATP sensitivity in human pancreatic beta-cells and rat INS-1 cells. J Physiol. 2008;586:1307–19.
Roberts OL, Dart C. cAMP signalling in the vasculature: the role of Epac (exchange protein directly activated by cAMP). Biochem Soc Trans. 2014;42:89–97.
Shibasaki T, Takahashi T, Takahashi H, Seino S. Cooperation between cAMP signalling and sulfonylurea in insulin secretion. Diabetes Obes Metab. 2014;16 Suppl 1:118–25.
Manoury B, Idres S, Leblais V, Fischmeister R. Ion channels as effectors of cyclic nucleotide pathways: Functional relevance for arterial tone regulation. Pharmacol Ther. 2020;209:107499.
Aromataris EC, Roberts ML, Barritt GJ, Rychkov GY. Glucagon activates Ca2+ and Cl− channels in rat hepatocytes. J Physiol. 2006;573:611–25.
Acknowledgements
The National Natural Science Foundation of China (Nos. 81973301, 81773701, and 82003732), the Medical Research Project of Jiangsu Commission of Health (No.ZDA2020006), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No. 18KJA310004), the Major Project of Nanjing Medical University (No. NMUD2018008), the Priority Academic Program Development of Jiangsu Higher Education Institutions. Thank Prof. Hai Wang for providing iptakalim in this study.
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RBG performed the in vivo experiments. YFD mainly charged with LSI and multimodal optical imaging and revised the manuscript. ZYC, XXH, and ZY mainly participated in in vitro experiments. JY, JJ, TFX, and YQS performed the Texas Red-gelatin to the coronary microvasculature and Immunofluorescence staining. HC, XQZ obtained resources and wrote paper. XLS designed research, acquired funding, and helped to draft the paper. All authors read and approved the final paper.
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Guo, Rb., Dong, Yf., Yin, Z. et al. Iptakalim improves cerebral microcirculation in mice after ischemic stroke by inhibiting pericyte contraction. Acta Pharmacol Sin 43, 1349–1359 (2022). https://doi.org/10.1038/s41401-021-00784-4
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DOI: https://doi.org/10.1038/s41401-021-00784-4
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