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Signaling Function of Na,K-ATPase Induced by Ouabain Against LPS As an Inflammation Model in Hippocampus

Abstract

Background: Ouabain (OUA) is a newly recognized hormone that is synthesized in the adrenal cortex and hypothalamus. Low doses of OUA can activate a signaling pathway by interaction with Na,K-ATPase, which is protective against a number of insults. OUA has central and peripheral anti-inflammatory effects. Lipopolysaccharide (LPS), via toll-like receptor 4 activation, is a widely used model to induce systemic inflammation. This study used a low OUA dose to evaluate its effects on inflammation induced by LPS injection in rats.

Methods: Adult male Wistar rats received acute intraperitoneal (ip) OUA (1.8 μg/kg) or saline 20 minutes before LPS (200 μg/kg, ip) or saline injection. Some of the animals had their femoral artery catheterized in order to assess arterial blood pressure values before and after OUA administration. Na,K-ATPase activity, cytokine mRNA levels, apoptosis-related proteins, NF-κB activation brain-derived neurotrophic factor BDNF, corticosterone and TNF-α levels were measured.

Results: OUA pretreatment decreased mRNA levels of the pro-inflammatory cytokines, inducible nitric oxide synthase (iNOS) and IL-1β, which are activated by LPS in the hippocampus, but with no effect on serum measures of these factors. None of these OUA effects were linked to Na,K-ATPase activity. The involvement of the inflammatory transcription factor NF-κB in the OUA effect was indicated by its prevention of LPS-induced nuclear translocation of the NF-κB subunit, RELA (p65), as well as the decreased cytosol levels of the NF-κB inhibitor, IKB, in the hippocampus. OUA pretreatment reversed the LPS-induced glial fibrillary acidic protein (GFAP) activation and associated inflammation in the dentate gyrus. OUA also prevented LPS-induced increases in the hippocampal Bax/Bcl2 ratio suggesting an anti-apoptotic action in the brain.

Conclusion: Our results suggest that a low dose of OUA has an important anti-inflammatory effect in the rat hippocampus. This effect was associated with decreased GFAP induction by LPS in the dentate gyrus, a brain area linked to adult neurogenesis.

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References
1.
Markus R, Cecon E, Pires-Lapa M . Immune-pineal axis: nuclear factor κB (NF-kB) mediates the shift in the melatonin source from pinealocytes to immune competent cells. Int J Mol Sci. 2013; 14(6):10979-97. PMC: 3709713. DOI: 10.3390/ijms140610979. View

2.
Laflamme N, Soucy G, Rivest S . Circulating cell wall components derived from gram-negative, not gram-positive, bacteria cause a profound induction of the gene-encoding Toll-like receptor 2 in the CNS. J Neurochem. 2001; 79(3):648-57. DOI: 10.1046/j.1471-4159.2001.00603.x. View

3.
Levenson R . Isoforms of the Na,K-ATPase: family members in search of function. Rev Physiol Biochem Pharmacol. 1994; 123:1-45. DOI: 10.1007/BFb0030902. View

4.
Xiao A, Wei L, Xia S, Rothman S, Yu S . Ionic mechanism of ouabain-induced concurrent apoptosis and necrosis in individual cultured cortical neurons. J Neurosci. 2002; 22(4):1350-62. PMC: 6757565. View

5.
Chen A, Xiong L, Tong Y, Mao M . The neuroprotective roles of BDNF in hypoxic ischemic brain injury. Biomed Rep. 2014; 1(2):167-176. PMC: 3956206. DOI: 10.3892/br.2012.48. View