Inhibitory Effect of Mao-Bushi-Saishin-to on Prostaglandin E2 Synthesis in C6 Rat Glioma Cells

Abstract

The Kampo medicine Mao-Bushi-Saishin-to (Ma-HuangFu-Zi-Xi-Xin-Tang in Chinese: MBS) is containing three herbal constituents of Mao (Ephedra herb), Bushi (Aconiti tuber) and Saishin (Asiasarum root), in a ratio of 4 : 1 : 3, and has long been prescribed the treatment of various inflammetry disease.1) MBS has been reported to be effective for the treatment of various symptoms of cold, especially nasal congestion and for seasonal allergic rhinitis.2,3) Recently, Ikeda et al., described the anti-allergic mechanism of MBS treated in long-period, 4) whereas acute effect of MBS is also reported. 5,6) In the previous report, we have demonstrated that Mao increased the cAMP content in RBL-2H3 cell and this effect account for its inhibitory effect on histamine-release and thus, the inhibitory effect on passive cutaneous anaphylaxis of MBS. 6) In the brain, prostaglandin E 2 (PGE 2 ) levels are very low or undetectable in normal conditions, but can rise during inflammatory processes, multiple sclerosis, and AIDS-associated dementia. 7,8) High levels of PGE 2 can affect the activities of several cell types, including neurons, glial, and endothelial cells, and can regulate microglia/macrophage and lymphocyte functions during inflammatory and immune processes.9) Therefore, the interplay between PGE 2 and other local factors, including pro-and anti-inflammatory cytokines, is likely to influence the outcome of inflammatory and immune responses in the central nervous system (CNS). Glial cells are assumed to be an important source of PGs in the CNS, 10) which are similar to macrophages in that they may be activated by bacterial endotoxin and/or cytokines to produce PGE 2 in the CNS. [11][12][13] Prostanoids, arachidonic acid metabolites produced from a variety of inflammatory cells upon stimulation, are thought to be involved in the pathogenesis of diseases. Prostanoid synthesis is regulated by two successive metabolic steps, the release of arachidonic acid from membrane phospholipids by phospholipase A 2 and its conversion to prostanoids by cyclooxygenase.14,15) Cytosolic PLA 2 (cPLA 2 ) is a ubiquitously distributed 85-kDa enzyme, the activation of which is tightly regulated by postreceptor transmembrane signaling. [16][17][18] cPLA 2 is activated by extracellular signal-regulated kinase (ERK)1/2 when cytosolic Ca 2ϩ concentrations are in the submicromolar or micromolar range. 19,20) It has been shown that glial cells express neurotransmitter receptors, including H 1 histaminergic receptor, 21) which are coupled to intracellular Ca 2ϩ mobilization, resulting activation of cPLA 2 . For the present studies we used rat C6 glioma cells because they are derived from astrocytes and express many astrocytic properties in culture. 22)Cyclic AMP can inhibit the ERK pathway in C6 glioma cells. 23,24) Furthermore, we have previously demonstrated that baicalein, a flavonoid contained in Scutellaria root, inhibited prostaglandin E 2 synthesis and the phosphorylation of ERK1/2 in C6 rat glioma cells.25) Therefore, in this report, we have stud...

Ephedrae herba (Mao) decreased histamine content in RBL-2H3 cells

“…MBS has been reported to be effective for the treatment of various cold symptoms, especially nasal congestion, and for seasonal allergic rhinitis [7,8]. Recently, we have shown that MBS inhibits release of histamine from RBL-2H3 cells and production of prostaglandin E 2 in C6 rat glioma cells, and that Mao accounts for these effects [9,10]. Since MBS is also prescribed as a prophylactic in some cases [7,11], we studied the effect of long-term treatment with Mao on the function of RBL-2H3 cells.…”

In Vivo Pharmacokinetic Analysis Utilizing Non-Targeted and Targeted Mass Spectrometry and In Vitro Assay against Transient Receptor Potential Channels of Maobushisaishinto and Its Constituent Asiasari Radix

“…On the other hand, Kamei et al (2000) reported a case study showing that MBST remitted inflammatory markers and fever; in brief, fever and C-reactive protein levels returned to normal in an elderly patient even though antibiotics did not improve the outcome [ 17 ]. Results of these clinical studies and some preclinical evidence [ 18 , 19 , 20 , 21 ] indicate that MBST may be effective against upper respiratory tract infection because of its anti-inflammatory effect and adjuvanticity.…”