Reduced c-Fos expression in orexin neurons of the lateral hypothalamic area and the locus coeruleus following injection of spinosin into mice
Abstract
Background: Spinosin, a major component of Samen Ziziphi spinosae, has been shown to modulate sedation and hypnosis; however, the underlying neuronal mechanisms of its stimulatory effects remain unclear.
Materials and methods: In the present study, we injected spinosin (15 mg/kg) or saline into mice, which were killed after 90 min. We isolated the brains, which were immunohistochemically stained for c-Fos as a biomarker for neuronal activation and assessed the expression profile of c-Fos in various sleep–arousal brain areas.
Results: Our findings revealed that there were no statistically significant differences in the expression of c-Fos in the nucleus accumbens and ventrolateral preoptic area, the vertical limb of the diagonal band nucleus, horizontal limb of the diagonal band nucleus, ventral tuberomammillary nucleus, ventral tegmental area, and dorsal raphe nucleus relative to saline between saline and spinosin-treated mice. Unlike saline, spinosin markedly decreased c-Fos expression in the lateral hypothalamic area (LHA) as well as the locus coeruleus (LC). Compared to the saline injection, the application of spinosin also resulted in a marked decrease in c-Fos expression in the LHA orexin neurons.
Conclusions: These findings suggest that spinosin administration results in a restricted pattern of c-Fos expression within the LHA orexin neurons and the LC, suggesting that this particular neuronal inactivation contributes to sedation and hypnosis.
Keywords: spinosinimmunohistochemistrylateral hypothalamic arealocus coeruleusorexin
References
- Clement HW, Gemsa D, Wesemann W. Serotonin-norepinephrine interactions: a voltammetric study on the effect of serotonin receptor stimulation followed in the N. raphe dorsalis and the Locus coeruleus of the rat. J Neural Transm Gen Sect. 1992; 88(1): 11–23.
- Deurveilher S, Lo H, Murphy JA, et al. Differential c-Fos immunoreactivity in arousal-promoting cell groups following systemic administration of caffeine in rats. J Comp Neurol. 2006; 498(5): 667–689.
- Dragunow M, Faull R. The use of c-fos as a metabolic marker in neuronal pathway tracing. J Neurosci Methods. 1989; 29(3): 261–265.
- Furutani N, Hondo M, Kageyama H, et al. Neurotensin co-expressed in orexin-producing neurons in the lateral hypothalamus plays an important role in regulation of sleep/wakefulness states. PLoS One. 2013; 8(4): e62391.
- Greco MA, Lu J, Wagner D, et al. c-Fos expression in the cholinergic basal forebrain after enforced wakefulness and recovery sleep. Neuroreport. 2000; 11(3): 437–440.
- Jongen-Rêlo AL, Voorn P, Groenewegen HJ. Immunohistochemical characterization of the shell and core territories of the nucleus accumbens in the rat. Eur J Neurosci. 1994; 6(8): 1255–1264.
- Jung InHo, Lee HE, Park SeJ, et al. Ameliorating effect of spinosin, a C-glycoside flavonoid, on scopolamine-induced memory impairment in mice. Pharmacol Biochem Behav. 2014; 120: 88–94.
- Liu J, Chen Bo, Yao S. Simultaneous analysis and identification of main bioactive constituents in extract of Zizyphus jujuba var. sapinosa (Zizyphi spinosi semen) by high-performance liquid chromatography-photodiode array detection-electrospray mass spectrometry. Talanta. 2007; 71(2): 668–675.
- Liu J, Zhai WM, Yang YX, et al. GABA and 5-HT systems are implicated in the anxiolytic-like effect of spinosin in mice. Pharmacol Biochem Behav. 2015; 128: 41–49.
- Mineur YS, Einstein EB, Bentham MP, et al. Expression of the 5-HT1A serotonin receptor in the hippocampus is required for social stress resilience and the antidepressant-like effects induced by the nicotinic partial agonist cytisine. Neuropsychopharmacology. 2015; 40(4): 938–946.
- Moore JT, Chen J, Han Bo, et al. Direct activation of sleep-promoting VLPO neurons by volatile anesthetics contributes to anesthetic hypnosis. Curr Biol. 2012; 22(21): 2008–2016.
- Muraki Yo, Yamanaka A, Tsujino N, et al. Serotonergic regulation of the orexin/hypocretin neurons through the 5-HT1A receptor. J Neurosci. 2004; 24(32): 7159–7166.
- Oishi Yo, Xu Qi, Wang Lu, et al. Slow-wave sleep is controlled by a subset of nucleus accumbens core neurons in mice. Nat Commun. 2017; 8(1): 734.
- Paxinos G. Franklin, KBJ. The Mouse Brainin Stereotaxic Coordinates. San Diego: Academic Press. 1997.
- Peyron C, Tighe DK, van den Pol AN, et al. Neurons containing hypocretin (orexin) project to multiple neuronal systems. J Neurosci. 1998; 18(23): 9996–10015.
- Rioja J, Santín LJ, López-Barroso D, et al. 5-HT1A receptor activation counteracted the effect of acute immobilization of noradrenergic neurons in the rat locus coeruleus. Neurosci Lett. 2007; 412(1): 84–88.
- Sanghera MK, McMillen BA, German DC. Buspirone, a non-benzodiazepine anxiolytic, increases locus coeruleus noradrenergic neuronal activity. Eur J Pharmacol. 1982; 86(1): 107–110.
- Saper CB, Scammell TE, Lu J. Hypothalamic regulation of sleep and circadian rhythms. Nature. 2005; 437(7063): 1257–1263.
- Scammell TE, Gerashchenko DY, Mochizuki T, et al. An adenosine A2a agonist increases sleep and induces Fos in ventrolateral preoptic neurons. Neuroscience. 2001; 107(4): 653–663.
- Schrader JA, Smale L, Nunez AA. Pregnancy affects FOS rhythms in brain regions regulating sleep/wake state and body temperature in rats. Brain Res. 2012; 1480: 53–60.
- Sherin JE, Shiromani PJ, McCarley RW, et al. Activation of ventrolateral preoptic neurons during sleep. Science. 1996; 271(5246): 216–219.
- Sim LJ, Selley DE, Tsai KP, et al. Calcium and cAMP mediated stimulation of Fos in cultured hypothalamic tyrosine hydroxylase-immunoreactive neurons. Brain Res. 1994; 653(1-2): 155–160.
- Ueta Y, Hara Y, Kitamura K, et al. Action sites of adrenomedullin in the rat brain: functional mapping by Fos expression. Peptides. 2001; 22(11): 1817–1824.
- Wang LE, Bai YJ, Shi XR, et al. Spinosin, a C-glycoside flavonoid from semen Zizhiphi Spinozae, potentiated pentobarbital-induced sleep via the serotonergic system. Pharmacol Biochem Behav. 2008; 90(3): 399–403.
- Wang LE, Cui XY, Cui SY, et al. Potentiating effect of spinosin, a C-glycoside flavonoid of Semen Ziziphi spinosae, on pentobarbital-induced sleep may be related to postsynaptic 5-HT(1A) receptors. Phytomedicine. 2010; 17(6): 404–409.
- Zanderigo F, Pantazatos S, Rubin-Falcone H, et al. In vivo relationship between serotonin 1A receptor binding and gray matter volume in the healthy brain and in major depressive disorder. Brain Struct Funct. 2018; 223(6): 2609–2625.
- Zhang JP, Xu Qi, Yuan XS, et al. Projections of nucleus accumbens adenosine A2A receptor neurons in the mouse brain and their implications in mediating sleep-wake regulation. Front Neuroanat. 2013; 7: 43.
- Zhang M, Zhang Y, Xie J. Simultaneous determination of jujuboside A, B and betulinic acid in semen Ziziphi spinosae by high performance liquid chromatography-evaporative light scattering detection. J Pharm Biomed Anal. 2008; 48(5): 1467–1470.
