Abstract
Spinal cord injury (SCI) causes motor, sensory, and autonomic dysfunctions. The gut microbiome has an important role in SCI, while short-chain fatty acids (SCFAs) are one of the main bioactive mediators of microbiota. In the present study, we explored the effects of oral administration of exogenous SCFAs on the recovery of locomotor function and tissue repair in SCI. Allen’s method was utilized to establish an SCI model in Sprague-Dawley (SD) rats. The animals received water containing a mixture of 150 mmol/L SCFAs after SCI. After 21 d of treatment, the Basso, Beattie, and Bresnahan (BBB) score increased, the regularity index improved, and the base of support (BOS) value declined. Spinal cord tissue inflammatory infiltration was alleviated, the spinal cord necrosis cavity was reduced, and the numbers of motor neurons and Nissl bodies were elevated. Enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (qPCR), and immunohistochemistry assay revealed that the expression of interleukin (IL)-10 increased and that of IL-17 decreased in the spinal cord. SCFAs promoted gut homeostasis, induced intestinal T cells to shift toward an anti-inflammatory phenotype, and promoted regulatory T (Treg) cells to secrete IL-10, affecting Treg cells and IL-17+ γδ T cells in the spinal cord. Furthermore, we observed that Treg cells migrated from the gut to the spinal cord region after SCI. The above findings confirm that SCFAs can regulate Treg cells in the gut and affect the balance of Treg and IL-17+ γδ T cells in the spinal cord, which inhibits the inflammatory response and promotes the motor function in SCI rats. Our findings suggest that there is a relationship among gut, spinal cord, and immune cells, and the “gut-spinal cord-immune” axis may be one of the mechanisms regulating neural repair after SCI.
摘要
脊髓损伤可以引起运动、感觉和自主神经功能障碍。肠道微生物组在脊髓损伤中具有重要作用,而短链脂肪酸是微生物群的主要生物活性介质之一。在本研究中,我们探讨了口服外源性短链脂肪酸对脊髓损伤运动功能恢复和组织修复的影响。采用Allen方法建立SD大鼠脊髓损伤模型。脊髓损伤后,动物接受含有150 mmol/L短链脂肪酸混合物的水。治疗21天后,BBB评分升高,步态的规律性指数改善,后肢步宽值下降。脊髓组织炎症浸润减轻,脊髓坏死腔减少,运动神经元和尼氏体数量升高。酶联免疫吸附测定(ELISA)、实时定量聚合酶链反应(qPCR)和免疫组化检测显示脊髓中白细胞介素-10(IL-10)表达升高,IL-17表达降低。短链脂肪酸能促进肠道稳态,诱导肠道T细胞转向抗炎表型,促进调节性T细胞(Treg)分泌IL-10,影响脊髓中的Treg细胞和IL-17+γδ T细胞。此外,我们观察到脊髓损伤后Treg细胞从肠道迁移到脊髓区域。以上结果证实,短链脂肪酸可调节肠道中的Treg细胞,影响脊髓中Treg和IL-17+γδ T细胞的平衡,抑制炎症反应,促进脊髓损伤大鼠的运动功能。我们的研究结果表明,肠道、脊髓和免疫细胞之间存在一定的关系,“肠道-脊髓-免疫”轴可能是脊髓损伤后神经修复的调节机制之一。
This is a preview of subscription content, log in via an institution to check access.
References
Allen AR, 1911. Surgery of experimental lesion of spinal cord equivalent to crush injury of fracture dislocation of spinal column: a preliminary report. JAMA, LVII(11):878–880. https://doi.org/10.1001/jama.1911.04260090100008
Basso DM, Beattie MS, Bresnahan JC, 1995. A sensitive and reliable locomotor rating scale for open field testing in rats. J Neurotrauma, 12(1): 1–21. https://doi.org/10.1089/neu.1995.12.!
Basso DM, Beattie MS, Bresnahan JC, et al., 1996. Mascis evaluation of open field locomotor scores: effects of experience and teamwork on reliability. J Neurotrauma, 13(7): 343–359. https://doi.org/10.1089/neu.1996.13.343
Bazzocchi G, Turroni S, Bulzamini MC, et al., 2021. Changes in gut microbiota in the acute phase after spinal cord injury correlate with severity of the lesion. Sci Rep, 11: 12743. https://doi.org/10.1038/s41598-021-92027-z
Benakis C, Brea D, Caballero S, et al., 2016. Commensal microbiota affects ischemic stroke outcome by regulating intestinal γδ T cells. Nat Med, 22(5):516–523. https://doi.org/10.1038/nm.4068
Bezkorovainy A, 2001. Probiotics: determinants of survival and growth in the gut. Am J Clin Nutr, 73(2):399S–405S. https://doi.org/10.1093/ajcn/73.2399s
Cervi AL, Lukewich MK, Lomax AE, 2014. Neural regulation of gastrointestinal inflammation: role of the sympathetic nervous system. Auton Neurosci, 182:83–88. https://doi.org/10.1016/j.autneu.2013.12.003
Dodd W, Motwani K, Small C, et al., 2022. Spinal cord injury and neurogenic lower urinary tract dysfunction: what do we know and where are we going? J Mens Health, 18(1):24. https://doi.org/10.31083/j.jomh1801024
Eli I, Lerner DP, Ghogawala Z, 2021. Acute traumatic spinal cord injury. Neurol Clin, 39(2):471–488. https://doi.org/10.1016/j.ncl.2021.02.004
Ferreira TM, Leonel AJ, Melo MA, et al., 2012. Oral supplementation of butyrate reduces mucositis and intestinal permeability associated with 5-fluorouracil administration. Lipids, 47(7):669–678. https://doi.org/10.1007/s11745-012-3680-3
Gungor B, Adiguzel E, Gursel I, et al., 2016. Intestinal microbiota in patients with spinal cord injury. PLoS ONE, 11(1): e0145878. https://doi.org/10.1371/journal.pone.0145878
He J, Zhao J, Peng X, et al., 2017. Molecular mechanism of miR-136-5p targeting NF-κB/A20 in the IL-17-mediated inflammatory response after spinal cord injury. Cell Physiol Biochem, 44(3):1224–1241. https://doi.org/10.1159/000485452
Hill F, Kim CF, Gorrie CA, et al., 2011. Interleukin-17 deficiency improves locomotor recovery and tissue sparing after spinal cord contusion injury in mice. Neurosci Lett, 487(3):363–367. https://doi.org/10.1016/j.neulet.2010.10.057
Huang R, Liu P, Bai YG, et al., 2022. Changes in the gut microbiota of osteoporosis patients based on 16S rRNA gene sequencing: a systematic review and meta-analysis. J Zhejiang Univ-Sci B (Biomed & Biotechnol), 23(12):1002–1013. https://doi.org/10.1631/jzus.B2200344
Huuskonen J, Suuronen T, Nuutinen T, et al., 2004. Regulation of microglial inflammatory response by sodium butyrate and short-chain fatty acids. Br J Pharmacol, 141 (5):874–880. https://doi.org/10.1038/sj.bjp.0705682
Jing YL, Yu Y, Bai F, et al., 2021a. Effect of fecal microbiota transplantation on neurological restoration in a spinal cord injury mouse model: involvement of brain-gut axis. Microbiome, 9:59. https://doi.org/10.1186/s40168-021-01007-y
Jing YL, Bai F, Yu Y, 2021b. Spinal cord injury and gut microbiota: a review. Life Sci, 266:118865. https://doi.org/10.1016/j.lfs.2020.118865
Jogia T, Ruitenberg MJ, 2020. Traumatic spinal cord injury and the gut microbiota: current insights and future challenges. Front Immunol, 11:704. https://doi.org/10.3389/fimmu.2020.00704
Kigerl KA, Hall JCE, Wang LL, et al., 2016. Gut dysbiosis impairs recovery after spinal cord injury. J Exp Med, 213(12): 2603–2620. https://doi.org/10.1084/jem.20151345
Kigerl KA, Mostacada K, Popovich PG, 2018. Gut microbiota are disease-modifying factors after traumatic spinal cord injury. Neurotherapeutics, 15(1):60–67. https://doi.org/10.1007/s13311-017-0583-2
Lane G, Gracely A, Bassis C, et al., 2022. Distinguishing features of the urinary bacterial microbiome in patients with neurogenic lower urinary tract dysfunction. J Urol, 207(3): 627–634. https://doi.org/10.1097/JU.0000000000002274
Lu YT, Liu HY, Yang K, et al., 2022. A comprehensive update: gastrointestinal microflora, gastric cancer and gastric premalignant condition, and intervention by traditional Chinese medicine. J Zhejiang Univ-Sci B (Biomed & Biotechnol), 23(1):1–18. https://doi.org/10.1631/jzus.B2100182
Lucas S, Omata Y, Hofmann J, et al., 2018. Short-chain fatty acids regulate systemic bone mass and protect from pathological bone loss. Nat Commun, 9:55. https://doi.org/10.1038/s41467-017-02490-4
Matt SM, Allen JM, Lawson MA, et al., 2018. Butyrate and dietary soluble fiber improve neuroinflammation associated with aging in mice. Front Immunol, 9:1832. https://doi.org/10.3389/fimmu.2018.01832
Michel M, Goldman M, Peart R, et al., 2021. Spinal cord injury: a review of current management considerations and emerging treatments. J Neurol Sci Res, 2(2):14.
Moriyama M, Nishimura Y, Kurebayashi R, et al., 2021. Acetate suppresses lipopolysaccharide-stimulated nitric oxide production in primary rat microglia but not in BV-2 microglia cells. Curr Mol Pharmacol, 14(2):253–260. https://doi.org/10.2174/1874467213666200420101048
Nakamura YK, Janowitz C, Metea C, et al., 2017. Short chain fatty acids ameliorate immune-mediated uveitis partially by altering migration of lymphocytes from the intestine. Sci Rep, 7:11745. https://doi.org/10.1038/s41598-017-12163-3
O’Connor G, Jeffrey E, Madorma D, et al., 2018. Investigation of microbiota alterations and intestinal inflammation postspinal cord injury in rat model. J Neurotrauma, 35(18): 2159–2166. https://doi.org/10.1089/neu.2017.5349
Park J, Kim M, Kang SG, et al., 2015. Short-chain fatty acids induce both effector and regulatory T cells by suppression of histone deacetylases and regulation of the mTOR-S6K pathway. Mucosal Immunol, 8(1):80–93. https://doi.org/10.1038/mi.2014.44
Park J, Goergen CJ, Hogenesch H, et al., 2016. Chronically elevated levels of short-chain fatty acids induce T cellmediated ureteritis and hydronephrosis. J Immunol, 196(5): 2388–2400. https://doi.org/10.4049/jimmunol.1502046
Patnala R, Arumugam TV, Gupta N, et al., 2017. HDAC inhibitor sodium butyrate-mediated epigenetic regulation enhances neuroprotective function of microglia during ischemic stroke. Mol Neurobiol, 54(8):6391–6411. https://doi.org/10.1007/s12035-016-0149-z
Ramos MG, Bambirra EA, Cara DC, et al., 1997. Oral administration of short-chain fatty acids reduces the intestinal mucositis caused by treatment with Ara-C in mice fed commercial or elemental diets. Nutr Cancer, 28(2):212–217. https://doi.org/10.1080/01635589709514577
Ratajczak W, Ryl A, Mizerski A, et al., 2019. Immunomodulatory potential of gut microbiome-derived short-chain fatty acids (SCFAs). Acta Biochim Pol, 66(1):1–12. https://doi.org/10.18388/abp.2018_2648
Silva YP, Bernardi A, Frozza RL, 2020. The role of short-chain fatty acids from gut microbiota in gut-brain communication. Front Endocrinol (Lausanne), 11:25. https://doi.org/10.3389/fendo.2020.00025
Stephenson J, Nutma E, van der Valk P, et al., 2018. Inflammation in CNS neurodegenerative diseases. Immunology, 154(2): 204–219. https://doi.org/10.1111/imm.12922
Sun GD, Yang SX, Cao GC, et al., 2018. y8 T cells provide the early source of IFN-γ to aggravate lesions in spinal cord injury. J Exp Med, 215(2):521–535. https://doi.org/10.1084/jem.20170686
Tate DG, Forchheimer M, Rodriguez G, et al., 2016. Risk factors associated with neurogenic bowel complications and dysfunction in spinal cord injury. Arch Phys Med Rehabil, 97(10):1679–1686. https://doi.org/10.1016/j.apmr.2016.03.019
Valido E, Bertolo A, Frankl GP, et al., 2022. Systematic review of the changes in the microbiome following spinal cord injury: animal and human evidence. Spinal Cord, 60(4): 288–300. https://doi.org/10.1038/s41393-021-00737-y
Wallace DJ, Sayre NL, Patterson TT, et al., 2019. Spinal cord injury and the human microbiome: beyond the brain-gut axis. Neurosurg Focus, 46(3):E11. https://doi.org/10.3171/2018.12.FOCUS18206
Xu P, Zhang F, Chang MM, et al., 2021. Recruitment of γδ T cells to the lesion via the CCL2/CCR2 signaling after spinal cord injury. J Neuroinflammation, 18:64. https://doi.org/10.1186/s12974-021-02115-0
Yu BB, Qiu HD, Cheng SP, et al., 2021. Profile of gut microbiota in patients with traumatic thoracic spinal cord injury and its clinical implications: a case-control study in a rehabilitation setting. Bioengineered, 12(1):4489–4499. https://doi.org/10.1080/21655979.2021.1955543
Zhang JX, Xie QS, Kong WM, et al., 2020. Short-chain fatty acids oppositely altered expressions and functions of intestinal cytochrome P4503A and P-glycoprotein and affected pharmacokinetics of verapamil following oral administration to rats. J Pharm Pharmacol, 72(3):448–460. https://doi.org/10.1111/jphp.13215
Acknowledgments
This work was supported by the National Natural Science Foundation of China (No. 82060399) and the Guangxi Medical High-level Key Talents Training “139” Program Training Project (No. [2020]15), China.
Author information
Authors and Affiliations
Corresponding authors
Additional information
Author contributions
Shaohui ZONG and Gaofeng ZENG performed the study concept and design. Pan LIU, Mingfu LIU, and Deshuang XI performed the experimental research and data analysis. Yiguang BAI established animal models. Ruixin MA and Yaoming MO contributed to the data analysis, writing and editing of the manuscript. All authors have read and approved the final manuscript, and therefore, have full access to all the data in the study and take responsibility for the integrity and security of the data.
Compliance with ethics guidelines
Pan LIU, Mingfu LIU, Deshuang XI, Yiguang BAI, Ruixin MA, Yaomin MO, Gaofeng ZENG, and Shaohui ZONG declare that there are no conflicts of interest associated with this manuscript.
All experimental procedures adhered to the Guidelines for Animal Treatment of Guangxi Medical University (approval No. 201810042) and were performed according to the principles and procedures of the National Institutes of Health (NIH Publication No. 85-23, revised 1996) Guide for the Care and Use of Laboratory Animals.
Rights and permissions
About this article
Cite this article
Liu, P., Liu, M., Xi, D. et al. Short-chain fatty acids ameliorate spinal cord injury recovery by regulating the balance of regulatory T cells and effector IL-17+ γδ T cells. J. Zhejiang Univ. Sci. B 24, 312–325 (2023). https://doi.org/10.1631/jzus.B2200417
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1631/jzus.B2200417
Key words
- Short-chain fatty acids (SCFAs)
- Spinal cord injury (SCI)
- Regulatory T cells
- IL-17+ γδ T cells
- Neuroprotection
- Inflammation
- Motor function recovery