The aim of this study was to investigate the mechanisms through which bacterial lipopolysaccharide (LPS) stimulates prostaglandin (PG) production in rat hypothalamic astroglial cells in vitro. The latter were treated with LPS alone or LPS plus antagonists of the interleukin-1 (IL-1) and nitric oxide (NO) pathways, and the subsequent changes in cyclooxygenase (COX) activity were monitored by measuring a COX end-product, prostaglandin E2 (PGE2), released into the incubation medium. LPS produced a concentration-dependent increase in PGE2 release from astroglia after 24 h incubation; experiments with selective antagonists showed that the increase in PGE 2 release induced by LPS may be, at least in part, mediated by IL-1 and NO.
References
1.
Hewett JA, Roth RAHepatic and extrahepatic pathobiology of bacterial lipopolysaccharide. Pharmacol Rev1993; 45: 381—411.
2.
Bone RCGram-negative sepsis. Background, clinical features and intervention. Chest1991; 101: 802—808.
3.
McDonald KR, Weise VK, Peterson REEffect of aspirin and reserpine on adrenocortical response to piromen in man . Proc Soc Exp Biol1956; 93: 343—348.
4.
Oka S., Arita H.Inflammatory factors stimulate expression of group II phospholipase A2 in rat cultured astrocytes. J Biol Chem1991; 266: 9956—9960.
5.
Ambs P., Baccarini M., Fitzke E. et al. Role of cytosolic phospholipase A2 in arachidonic acid release of rat liver macrophages: regulation by Ca2+ and phosphorylation. Biochem J1995; 311: 189—195.
6.
Campbell WB, Halushka PVLipid-derived autacoids. In: Hardman JG, Limbird LE, Molinoff PB et al. (eds) Goodman & Gilman's The Pharmacological Basis of Therapeutics , 9th edn. New York, NY: McGraw-Hill; 1996: 601—616.
Habib A., Creminon C., Frobert Y. et al. Demonstration of an inducible cyclooxygenase in human endothelial cells using antibodies raised against the carboxyl-terminal region of the cyclooxygenase-2. J Biol Chem1993; 268: 23448—23454.
9.
Akarasereenont P., Bakhle YS, Thiemerrmann C. et al. Cytokine-mediated induction of cyclo-oxygenase-2 by activation of tyrosine kinase in bovine endothelial cells stimulated by bacterial lipopolysaccharide. Br J Pharmacol1995; 115: 401—408.
10.
Lee SH, Soyoola E., Chanmugam P. et al. Selective expression of mitogen-inducible cyclooxygenase in macrophages stimulated with lipopolysaccharide. J Biol Chem1992; 267: 25934—25938.
11.
Quan N., Sundar SK, Weiss JMInduction of interleukin-1 in various brain regions after peripheral and central injections of lipopolysaccharide. J Neuroimmunol1993; 49: 125—134.
12.
Vane JR, Mitchell JA, Appleton I. et al. Inducible isoforms of cyclooxygenase and nitric-oxide synthase in inflammation. Proc Natl Acad Sci USA1994 ; 91: 2046—2050.
13.
Merrill JETumor necrosis factor alpha, interleukin 1 and related cytokines in brain development: normal and pathological. Dev Neurosci1992; 14: 1—10.
14.
Benveniste ENInflammatory cytokines within the central nervous system: sources, function and mechanisms of action. Am J Physiol1992; 263: C1—C16.
15.
Yamagata K. , Andreasson KI, Kaufmann WE et al. Expression of a mitogen-inducible cyclooxygenase in brain neurons: regulation by synaptic activity and glucocorticoids. Neuron1993; 11: 371—386.
16.
Galea E., Reis DJ, Feinstein DLCloning and expression of inducible nitric oxide synthase from rat astrocytes . J Neurosci Res1994; 37: 406—411.
17.
McCarthy KD , De Vellis J.Preparation of separate astroglial and oligodendroglial cell cultures from rat cerebral tissue. J Cell Biol1980; 85: 890—902.
18.
Mirtella A. , Tringali G., Guerriero G. et al. Evidence that interleukin-1β-induced prostaglandin E2 release from rat hypothalamus is mediated by both type I and type II receptors. J Neuroimmunol1995 ; 61: 171—177.
19.
Pistritto G. , Mancuso C., Tringali G. et al. Relative contribution of constitutive and inducible cyclo-oxygenase activity to lipopolysaccharide-induced prostaglandin production by primary cultures of rat hypothalamic astrocytes. Neurosci Lett1998; 246: 45—48.
20.
Pistritto G. , Franzese O., Pozzoli G. et al. Bacterial lipopolysaccharide increases prostaglandin production by rat astrocytes via inducible cyclo-oxygenase. Evidence for the involvement of nuclear factor κB. Biochem Biophys Res Commun1999; 263: 570—574.
21.
Smith WL, Garavito RM, DeWitt DLProstaglandin endoperoxide H synthases (cyclooxygenases)-1 and -2. J Biol Chem1996; 271: 33157—33160.
22.
O'Banion MK , Miller JC, Chang JW et al. Interleukin-1β induces prostaglandin G/H synthase-2 (cyclooxygenase-2) in primary murine astrocyte cultures. J Neurochem1996; 66: 2532—2540.
23.
Mollace V., Colasanti M., Muscoli C. et al. The effect of nitric oxide on cytokine-induced release of PGE2 by human cultured astroglial cells. Br J Pharmacol1998; 124: 742—746.
24.
Luheshi G., Miller AJ, Brouwer S. et al. Interleukin-1 receptor antagonist inhibits fever and systemic interleukin-6 induction in the rat. Am J Physiol1996; 270: E91—E95.
25.
Minghetti L., Polazzi E., Nicolini A. et al. Interferon-γ and nitric oxide down-regulate lipopolysaccharide-induced prostanoid production in cultured rat microglial cells by inhibiting cyclooxygenase-2 expression. J Neurochem1996; 66: 1963—1970.
26.
Rettori V., Gimeno M., Lyson K. et al. Nitric oxide mediates norepinephrine-induced prostaglandin E2 release from the hypothalamus. Proc Natl Acad Sci USA1992; 89: 11543—11546.
27.
Mancuso C., Tringali G., Grossman A. et al. The generation of nitric oxide and carbon monoxide produces opposite effects on the release of immunoreactive interleukin-1β from the rat hypothalamus in vitro: evidence for the involvement of different signaling pathways. Endocrinology1998; 139:1031—1037.
