Effect of Estrogen Therapy on TNF-α and iNOS Gene Expression in Spinal Cord Injury Model

  • Akram Amini Pishva Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • Mohammad Akbari Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • Akram Farahabadi Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • Ali Arabkheradmand Department of Surgery, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • Cordian Beyer Institute of Neuroanatomy, RWTH Aachen University, Aachen, Germany.
  • Nasrin Dashti School of Allied Health Sciences, Tehran University of Medical Sciences, Tehran, Iran.
  • Fatemeh Moradi Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
  • Gholamreza Hassanzadeh Mail Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Spinal cord injury, Tumor necrosis alpha, Inducible nitric oxide synthase, Estrogen, Iran


Spinal cord injury (SCI) is a crucial complication that results in neurons degeneration. The SCI lead to triggering of secondary complications such as inflammation that in turn has a key role in neurodegeneration development. The previous studies showed that TNF-α and iNOS genes expression increased significantly after SCI. As a consequence, these genes overexpression intensify the inflammation and neuron degeneration process. In the present study, 32 male Wistar rats were chased and divided into four groups of eight. The SCI were induced in three groups and another group used as a sham. The estrogen hormone used as a therapeutic agent in rats with SCI. The results showed that injection of 10 μg/kg/12h estrogen hormone reduced the TNF-α and iNOS genes expression significantly and confirmed the role of progesterone in the reduction of inflammation reduce the inflammation. The numbers of intact neurons in Estrogen group were higher than other groups and showed that progesterone has protective effects on neuron death. The BBB test was performed and demonstrated that estrogen is an effective factor in the improvement of locomotor response. Our results suggested that estrogen hormone with anti-inflammatory activity can be an efficient agent for SCI complications therapy.


Ackery A, Tator C, Krassioukov A. A global perspective on spinal cord injury epidemiology. Journal of neurotrauma. 2004;21(10):1355-70.

Allen AR. Surgery of experimental lesion of spinal cord equivalent to crush injury of fracture dislocation of spinal column: a preliminary report. Journal of the American Medical Association. 1911;57(11):878-80.

Anderson DK, Means ED, Waters TR, et al. Microvascular perfusion and metabolism in injured spinal cord after methylprednisolone treatment. Journal of neurosurgery. 1982;56(1):106-13.

Tator CH, Fehlings MG. Review of the secondary injury theory of acute spinal cord trauma with emphasis on vascular mechanisms. Journal of neurosurgery. 1991;75(1):15-26.

Sekhon LH, Fehlings MG. Epidemiology, demographics, and pathophysiology of acute spinal cord injury. Spine. 2001;26(24S):S2-S12.

Bartholdi D, Schwab ME. Expression of pro‐inflammatory cytokine and chemokine mRNA upon experimental spinal cord injury in mouse: An in situ hybridization study. European Journal of Neuroscience. 1997;9(7):1422-38.

HSU CY, DIMITRIJEVIC MR. Methylprednisolone in spinal cord injury: the possible mechanism of action. Journal of neurotrauma. 1990;7(3):115-9.

Pannu R, Barbosa E, Singh AK, et al. Attenuation of acute inflammatory response by atorvastatin after spinal cord injury in rats. Journal of neuroscience research. 2005;79(3):340-50.

Stirling DP, Khodarahmi K, Liu J, et al. Minocycline treatment reduces delayed oligodendrocyte death, attenuates axonal dieback, and improves functional outcome after spinal cord injury. The Journal of neuroscience. 2004;24(9):2182-90.

Teng YD, Choi H, Onario RC, et al. Minocycline inhibits contusion-triggered mitochondrial cytochrome c release and mitigates functional deficits after spinal cord injury. Proceedings of the National Academy of Sciences of the United States of America. 2004;101(9):3071-6.

Hsu CY, Doster K, Hu ZY. Cell-mediated injury, in: K. Narayan, J.E. Wilberger Jr., P.T. Polishock _Eds.., Neurotrauma: A Comprehensive Textbook of Head and Spinal Cord injury, McGraw-Hill, St. Louis, MO, 1996: 1433–44.

Rothwell NJ, Luheshi G, Toulmond S. Cytokines and their receptors in the central nervous system: physiology, pharmacology, and pathology. Pharmacology & therapeutics. 1996;69(2):85-95.

HAYASHI M, UEYAMA T, NEMOTO K, et al. Sequential mRNA expression for immediate early genes, cytokines, and neurotrophins in spinal cord injury. Journal of neurotrauma. 2000;17(3):203-18.

Wang CX, Olschowka JA, Wrathall JR. Increase of interleukin-1β mRNA and protein in the spinal cord following experimental traumatic injury in the rat. Brain research. 1997;759(2):190-6.

Wang CX, Nuttin B, Heremans H, et al. Production of tumor necrosis factor in spinal cord following traumatic injury in rats. Journal of neuroimmunology. 1996;69(1):151-6.

Yakovlev A, Faden A. Sequential expression of c-fos protooncogene, TNF-alpha, and dynorphin genes in spinal cord following experimental traumatic injury. Molecular and Chemical Neuropathology. 1994;23(2-3):179-90.

Streit WJ, Semple-Rowland SL, Hurley SD, et al. Cytokine mRNA profiles in contused spinal cord and axotomized facial nucleus suggest a beneficial role for inflammation and gliosis. Experimental neurology. 1998;152(1):74-87.

Benveniste EN. Inflammatory cytokines within the central nervous system: sources, function, and mechanism of action. American Journal of Physiology-Cell Physiology. 1992;263(1):C1-C16.

Lieberman AP, Pitha PM, Shin HS, et al. Production of tumor necrosis factor and other cytokines by astrocytes stimulated with lipopolysaccharide or a neurotropic virus. Proceedings of the National Academy of Sciences. 1989;86(16):6348-52.

Knoblach SM, Fan L, Faden AI. Early neuronal expression of tumor necrosis factor-α after experimental brain injury contributes to neurological impairment. Journal of neuroimmunology. 1999;95(1):115-25.

Sharief MK, Hentges R. Association between tumor necrosis factor-α and disease progression in patients with multiple sclerosis. New England Journal of Medicine. 1991;325(7):467-72.

Schreck R, Rieber P, Baeuerle PA. Reactive oxygen intermediates as apparently widely used messengers in the activation of the NF-kappa B transcription factor and HIV-1. The EMBO journal. 1991;10(8):2247.

Scheinman RI, Gualberto A, Jewell CM, et al. Characterization of mechanisms involved in transrepression of NF-kappa B by activated glucocorticoid receptors. Molecular and cellular biology. 1995;15(2):943-53.

Mukaida N, Morita M, Ishikawa Y, et al. Novel mechanism of glucocorticoid-mediated gene repression. Nuclear factor-kappa B is target for glucocorticoid-mediated interleukin 8 gene repression. Journal of Biological Chemistry. 1994;269(18):13289-95.

Grell M, Zimmermann G, Hülser D, et al. TNF receptors TR60 and TR80 can mediate apoptosis via induction of distinct signal pathways. The Journal of immunology. 1994;153(5):1963-72.

Caldenhoven E, Liden J, Wissink S, et al. Negative cross-talk between RelA and the glucocorticoid receptor: a possible mechanism for the antiinflammatory action of glucocorticoids. Molecular endocrinology. 1995;9(4):401-12.

Hurn PD, Macrae IM. Estrogen as a neuroprotectant in stroke. Journal of Cerebral Blood Flow & Metabolism. 2000;20(4):631-52.

Bebo BF, Fyfe-Johnson A, Adlard K, et al. Low-dose estrogen therapy ameliorates experimental autoimmune encephalomyelitis in two different inbred mouse strains. The Journal of Immunology. 2001;166(3):2080-9.

Ito A, Bebo BF, Matejuk A, et al. Estrogen treatment down-regulates TNF-α production and reduces the severity of experimental autoimmune encephalomyelitis in cytokine knockout mice. The Journal of Immunology. 2001;167(1):542-52.

Jansson L, Olsson T, Holmdahl R. Estrogen induces a potent suppression of experimental autoimmune encephalomyelities and collagen-induced arthritis in mice. Journal of neuroimmunology. 1994;53(2):203-7.

Liao S-L, Chen W-Y, Kuo J-S, et al. Association of serum estrogen level and ischemic neuroprotection in female rats. Neuroscience letters. 2001;297(3):159-62.

Matejuk A, Bakke AC, Hopke C, et al. Estrogen treatment induces a novel population of regulatory cells, which suppresses experimental autoimmune encephalomyelitis. Journal of neuroscience research. 2004;77(1):119-26.

Matejuk A, Dwyer J, Hopke C, et al. 17Beta-estradiol treatment profoundly down-regulates gene expression in spinal cord tissue in mice protected from experimental autoimmune encephalomyelitis. ARCHIVUM IMMUNOLOGIAE ET THERAPIAE EXPERIMENTALIS-ENGLISH EDITION-. 2003;51(3):185-94.

Palaszynski KM, Liu H, Loo KK, et al. Estriol treatment ameliorates disease in males with experimental autoimmune encephalomyelitis: implications for multiple sclerosis. Journal of neuroimmunology. 2004;149(1):84-9.

Saleh TM, Cribb AE, Connell BJ. Reduction in infarct size by local estrogen does not prevent autonomic dysfunction after stroke. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology. 2001;281(6):R2088-R95.

Yune TY, Kim SJ, Lee SM, et al. Systemic administration of 17β-estradiol reduces apoptotic cell death and improves functional recovery following traumatic spinal cord injury in rats. Journal of neurotrauma. 2004;21(3):293-306.

Bruce-Keller AJ, Keeling JL, Keller JN, et al. Antiinflammatory Effects of Estrogen on Microglial Activation 1. Endocrinology. 2000;141(10):3646-56.

Moosmann B, Behl C. The antioxidant neuroprotective effects of estrogens and phenolic compounds are independent from their estrogenic properties. Proceedings of the National Academy of Sciences. 1999;96(16):8867-72.

Ruiz-Larrea MB, Martı́n C, Martı́nez R, et al. Antioxidant activities of estrogens against aqueous and lipophilic radicals; differences between phenol and catechol estrogens. Chemistry and Physics of Lipids. 2000;105(2):179-88.

Vegeto E, Belcredito S, Etteri S, et al. Estrogen receptor-α mediates the brain antiinflammatory activity of estradiol. Proceedings of the National Academy of Sciences. 2003;100(16):9614-9.

Vegeto E, Ghisletti S, Meda C, et al. Regulation of the lipopolysaccharide signal transduction pathway by 17β-estradiol in macrophage cells. The Journal of steroid biochemistry and molecular biology. 2004;91(1):59-66.

Xu J, Fan G, Chen S, et al. Methylprednisolone inhibition of TNF-α expression and NF-kB activation after spinal cord injury in rats. Molecular brain research. 1998;59(2):135-42.

Zendedel A, Johann S, Mehrabi S, et al. Activation and Regulation of NLRP3 Inflammasome by Intrathecal Application of SDF-1a in a Spinal Cord Injury Model. Molecular neurobiology. 2015:1-13.

Lee YB, Yune TY, Baik SY, et al. Role of tumor necrosis factor-α in neuronal and glial apoptosis after spinal cord injury. Experimental neurology. 2000;166(1):190-5.

Bracken MB, Shepard MJ, Collins WF, et al. A randomized, controlled trial of methylprednisolone or naloxone in the treatment of acute spinal-cord injury: results of the Second National Acute Spinal Cord Injury Study. New England Journal of Medicine. 1990;322(20):1405-11.

Bracken MB, Shepard MJ, Collins Jr WF, et al. Methylprednisolone or naloxone treatment after acute spinal cord injury: 1-year follow-up data: results of the second National Acute Spinal Cord Injury Study. Journal of neurosurgery. 1992;76(1):23-31.

Auphan N, DiDonato JA, Rosette C, et al. Immunosuppression by glucocorticoids: inhibition of NF-kappaB activity through induction of IkappaB synthesis. Science. 1995;270(5234):286.

Bethea JR, Castro M, Keane RW, et al. Traumatic spinal cord injury induces nuclear factor-κB activation. The Journal of neuroscience. 1998;18(9):3251-60.

Beckman JS, Koppenol WH. Nitric oxide, superoxide, and peroxynitrite: the good, the bad, and ugly. American Journal of Physiology-Cell Physiology. 1996;271(5):C1424-C37.

Safe S, Kim K. Non-classical genomic estrogen receptor (ER)/specificity protein and ER/activating protein-1 signaling pathways. Journal of molecular endocrinology. 2008;41(5):263-75.

De Bosscher K, Berghe WV, Haegeman G. Cross-talk between nuclear receptors and nuclear factor κB. Oncogene. 2006;25(51):6868-86.

Sheldahl L, Marriott L, Bryant D, et al. Neuroprotective effects of estrogen and selective estrogen receptor modulators begin at the plasma membrane. Minerva endocrinologica. 2007;32(2):87.

Du S, Rubin A, Klepper S, et al. Calcium influx and activation of calpain I mediate acute reactive gliosis in injured spinal cord. Experimental neurology. 1999;157(1):96-105.

How to Cite
Amini Pishva A, Akbari M, Farahabadi A, Arabkheradmand A, Beyer C, Dashti N, Moradi F, Hassanzadeh G. Effect of Estrogen Therapy on TNF-α and iNOS Gene Expression in Spinal Cord Injury Model. Acta Med Iran. 54(5):296-301.
Original Article(s)