Cytosolic phospholipase A2α regulates induction of brain cyclooxygenase-2 in a mouse model of inflammation

2005 ◽  
Vol 288 (6) ◽  
pp. R1774-R1782 ◽  
Author(s):  
Adam Sapirstein ◽  
Hideyuki Saito ◽  
Sarah J. Texel ◽  
Tarek A. Samad ◽  
Eileen O’Leary ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Inflammatory Responses ◽  
Arachidonic Acid Metabolism ◽  
Cyclooxygenase 2 ◽  
Phospholipase A ◽  
Wild Type ◽  
Cytosolic Phospholipase ◽  
The Central Nervous System ◽  
Cox 2 ◽  
The Brain

The products of arachidonic acid metabolism are key mediators of inflammatory responses in the central nervous system, and yet we do not know the mechanisms of their regulation. The phospholipase A2 enzymes are sources of cellular arachidonic acid, and the enzymes cyclooxygenase-2 (COX-2) and microsomal PGE synthase-1 (mPGES-1) are essential for the synthesis of inflammatory PGE2 in the brain. These studies seek to determine the function of cytosolic phospholipase A2α (cPLA2α) in inflammatory PGE2 production in the brain. We wondered whether cPLA2α functions in inflammation to produce arachidonic acid or to modulate levels of COX-2 or mPGES-1. We investigated these questions in the brains of wild-type mice and mice deficient in cPLA2α (cPLA2α−/−) after systemic administration of LPS. cPLA2α−/− mice had significantly less brain COX-2 mRNA and protein expression in response to LPS than wild-type mice. The reduction in COX-2 was most apparent in the cells of the cerebral blood vessels and the leptomeninges. The brain PGE2 concentration of untreated cPLA2α−/− mice was equal to their wild-type littermates. After LPS treatment, however, the brain concentration of PGE2 was significantly less in cPLA2α−/− than in cPLA2α+/+ mice (24.4 ± 3.8 vs. 49.3 ± 11.6 ng/g). In contrast to COX-2, mPGES-1 RNA levels increased equally in both mouse genotypes, and mPGES-1 protein was unaltered 6 h after LPS. We conclude that cPLA2α regulates COX-2 levels and modulates inflammatory PGE2 levels. These results indicate that cPLA2α inhibition is a novel anti-inflammatory strategy that modulates, but does not completely prevent, eicosanoid responses.

Arachidonic Acid Derivatives and Neuroinflammation

2021 ◽  
Vol 20 ◽  
Author(s):  
Era Gorica ◽  
Vincenzo Calderone
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Arachidonic Acid ◽  
Prostaglandin E2 ◽  
Phospholipase A2 ◽  
Inflammatory Responses ◽  
The Central Nervous System ◽  
The Brain ◽  
Arachidonic Acid Derivatives

: Neuroinflammation is characterized by dysregulated inflammatory responses localized within the brain and spinal cord. Neuroinflammation plays a pivotal role in the onset of several neurodegenerative disorders and is considered a typical feature of these disorders. Microglia perform primary immune surveillance and macrophage-like activities within the central nervous system. Activated microglia are predominant players in the central nervous system response to damage related to stroke, trauma, and infection. Moreover, microglial activation per se leads to a proinflammatory response and oxidative stress. During the release of cytokines and chemokines, cyclooxygenases and phospholipase A2 are stimulated. Elevated levels of these compounds play a significant role in immune cell recruitment into the brain. Cyclic phospholipase A2 plays a fundamental role in the production of prostaglandins by releasing arachidonic acid. In turn, arachidonic acid is biotransformed through different routes into several mediators that are endowed with pivotal roles in the regulation of inflammatory processes. Some experimental models of neuroinflammation exhibit an increase in cyclic phospholipase A2, leukotrienes, and prostaglandins such as prostaglandin E2, prostaglandin D2, or prostacyclin. However, findings on the role of the prostacyclin receptors have revealed that their signalling suppresses Th2-mediated inflammatory responses. In addition, other in vitro evidence suggests that prostaglandin E2 may inhibit the production of some inflammatory cytokines, attenuating inflammatory events such as mast cell degranulation or inflammatory leukotriene production. Based on these conflicting experimental data, the role of arachidonic acid derivatives in neuroinflammation remains a challenging issue.

scholarly journals Effects of shinbuto and ninjinto on prostaglandin E2 production in lipopolysaccharide-treated human gingival fibroblasts

2017 ◽  
Author(s):  
Toshiaki Ara ◽  
Norio Sogawa
Keyword(s):  
Arachidonic Acid ◽  
Prostaglandin E2 ◽  
Experimental Model ◽  
Inflammatory Responses ◽  
Inflammatory Diseases ◽  
Human Gingival Fibroblasts ◽  
Gingival Fibroblasts ◽  
Arachidonic Acid Cascade ◽  
Cytosolic Phospholipase ◽  
Cox 2

Previously, we revealed that several kampo medicines that are used for patients with excess and/or medium patterns [kakkonto (TJ-1), shosaikoto (TJ-9), hangeshashinto (TJ-14), and orento (TJ-120)] reduced prostaglandin (PG)E<2 levels using LPS-treated human gingival fibroblasts (HGFs). Recently, we examined other kampo medicines used for patients with the deficiency pattern [bakumondoto (TJ-29), shinbuto (TJ-30), ninjinto (TJ-32), and hochuekkito (TJ-41)] and the herbs comprising shinbuto and ninjinto using the same experimental model. Shinbuto and ninjinto concentration-dependently reduced LPS-induced PGE2 production by HGFs, whereas hochuekkito weakly reduced and bakumondoto did not reduce PGE2 production. Shinbuto and ninjinto did not alter cyclooxygenase (COX) activity or the expression of molecules involved in the arachidonic acid cascade. Therefore, we next examined which herbs compromising shinbuto and ninjinto reduce LPS-induced PGE2 production. Among these herbs, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly and concentration-dependently decreased LPS-induced PGE2 production. However, both shokyo and kankyo increased the expression of cytosolic phospholipase (cPL)A2 but did not affect annexin1 or COX-2 expression. These results suggest that shokyo and kankyo suppress cPLA2 activity. We demonstrated that kampo medicines suppress inflammatory responses in patients with the deficiency pattern, and in those with excess or medium patterns. Moreover, kampo medicines that contain shokyo or kankyo are considered to be effective for the treatment of inflammatory diseases.

scholarly journals Effects of shinbuto and ninjinto on prostaglandin E2 production in lipopolysaccharide-treated human gingival fibroblasts

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e4120 ◽  
Author(s):  
Toshiaki Ara ◽  
Norio Sogawa
Keyword(s):  
Arachidonic Acid ◽  
Prostaglandin E2 ◽  
Experimental Model ◽  
Inflammatory Responses ◽  
Inflammatory Diseases ◽  
Human Gingival Fibroblasts ◽  
Gingival Fibroblasts ◽  
Arachidonic Acid Cascade ◽  
Cytosolic Phospholipase ◽  
Cox 2

Previously, we revealed that several kampo medicines used for patients with excess and/or medium patterns (kakkonto (TJ-1), shosaikoto (TJ-9), hangeshashinto (TJ-14), and orento (TJ-120)) reduced prostaglandin (PG)E2 levels using LPS-treated human gingival fibroblasts (HGFs). Recently, we examined other kampo medicines used for patients with the deficiency pattern [bakumondoto (TJ-29), shinbuto (TJ-30), ninjinto (TJ-32), and hochuekkito (TJ-41)] and the herbs comprising shinbuto and ninjinto using the same experimental model. Shinbuto and ninjinto concentration-dependently reduced LPS-induced PGE2 production by HGFs, whereas hochuekkito weakly reduced and bakumondoto did not reduce PGE2 production. Shinbuto and ninjinto did not alter cyclooxygenase (COX) activity or the expression of molecules involved in the arachidonic acid cascade. Therefore, we next examined which herbs compromising shinbuto and ninjinto reduce LPS-induced PGE2 production. Among these herbs, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly and concentration-dependently decreased LPS-induced PGE2 production. However, both shokyo and kankyo increased the expression of cytosolic phospholipase (cPL)A2 but did not affect annexin1 or COX-2 expression. These results suggest that shokyo and kankyo suppress cPLA2 activity. We demonstrated that kampo medicines suppress inflammatory responses in patients with the deficiency pattern, and in those with excess or medium patterns. Moreover, kampo medicines that contain shokyo or kankyo are considered to be effective for the treatment of inflammatory diseases.

scholarly journals Zymosan-induced glycerylprostaglandin and prostaglandin synthesis in resident peritoneal macrophages: roles of cyclo-oxygenase-1 and -2

2006 ◽  
Vol 399 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Carol A. Rouzer ◽  
Susanne Tranguch ◽  
Haibin Wang ◽  
Hao Zhang ◽  
Sudhansu K. Dey ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Peritoneal Macrophages ◽  
Prostaglandin Synthesis ◽  
Wild Type ◽  
Cytosolic Phospholipase ◽  
Cytosolic Phospholipase A2α ◽  
Cox 2 ◽  
Cox 1 ◽  
Exogenous Substrates

COX [cyclo-oxygenase; PG (prostaglandin) G/H synthase] oxygenates AA (arachidonic acid) and 2-AG (2-arachidonylglycerol) to endoperoxides that are converted into PGs and PG-Gs (glycerylprostaglandins) respectively. In vitro, 2-AG is a selective substrate for COX-2, but in zymosan-stimulated peritoneal macrophages, PG-G synthesis is not sensitive to selective COX-2 inhibition. This suggests that COX-1 oxygenates 2-AG, so studies were carried out to identify enzymes involved in zymosan-dependent PG-G and PG synthesis. When macrophages from COX-1−/− or COX-2−/− mice were treated with zymosan, 20–25% and 10–15% of the PG and PG-G synthesis observed in wild-type cells respectively was COX-2 dependent. When exogenous AA and 2-AG were supplied to COX-2−/− macrophages, PG and PG-G synthesis was reduced as compared with wild-type cells. In contrast, when exogenous substrates were provided to COX-1−/− macrophages, PG-G but not PG synthesis was reduced. Product synthesis also was evaluated in macrophages from cPLA2α (cytosolic phospholipase A2α)−/− mice, in which zymosan-induced PG synthesis was markedly reduced, and PG-G synthesis was increased approx. 2-fold. These studies confirm that peritoneal macrophages synthesize PG-Gs in response to zymosan, but that this process is primarily COX-1-dependent, as is the synthesis of PGs. They also indicate that the 2-AG and AA used for PG-G and PG synthesis respectively are derived from independent pathways.

Acute arsenic treatment alters arachidonic acid and its associated metabolite levels in the brain of C57Bl/6 mice

2014 ◽  
Vol 92 (8) ◽  
pp. 693-702 ◽  
Author(s):  
Anwar Anwar-Mohamed ◽  
Osama H. Elshenawy ◽  
Ahmed A. El-Sherbeni ◽  
Mohamed Abdelrady ◽  
Ayman O.S. El-Kadi
Keyword(s):  
Arachidonic Acid ◽  
Cytochrome P450 ◽  
Catalytic Activity ◽  
Activity Levels ◽  
Epoxyeicosatrienoic Acid ◽  
Mediated Effects ◽  
Cytosolic Phospholipase ◽  
Subsequent Decrease ◽  
Cox 2 ◽  
The Brain

The toxic effects of arsenic on the whole brain, as well as the discrete regions, has been previously reported for mice. We investigated the effects of acute arsenite (As(III)) on brain levels of arachidonic acid (AA) and its associated metabolites generated through cytochrome P450 (CYP), cyclooxygenase (COX), and lipoxygenase (LOX) pathways. Our results demonstrated that acute As(III) treatment (12.5 mg·(kg body mass)−1) decreases cytosolic phospholipase A2 (cPLA2) with a subsequent decrease in its catalytic activity and brain AA levels. In addition, As(III) differentially altered CYP epoxygenases and CYP ω-hydroxylases, but it did not affect brain Ephx2 mRNA or sEH catalytic activity levels. As(III)-mediated effects on Cyps caused an increase in brain 5,6-epoxyeicosatrienoic acid (5,6-EET) and 16/17-hydroxyeicosatetreinoic acid (16/17-HETE) levels, and a decrease in 18- and 20-HETE levels. Furthermore, As(III) increased cyclooxygenase-2 (COX-2) mRNA while decreasing prostaglandins F2α (PGF2α) and PGJ2. As(III) also increased brain 5-lipoxygenase (5-LOX) and 15-LOX mRNA, but decreased 12-LOX mRNA. These changes in LOX mRNA were associated with a decrease in 8/12-HETE levels only. In conclusion, this is the first demonstration that As(III) decreases AA levels coinciding with alterations to EET, HETE, and PG levels, which affects brain development and neurochemistry.

scholarly journals Effects of shinbuto and ninjinto on prostaglandin E2 production in lipopolysaccharide-treated human gingival fibroblasts

2017 ◽  
Author(s):  
Toshiaki Ara ◽  
Norio Sogawa
Keyword(s):  
Arachidonic Acid ◽  
Prostaglandin E2 ◽  
Experimental Model ◽  
Inflammatory Responses ◽  
Inflammatory Diseases ◽  
Human Gingival Fibroblasts ◽  
Gingival Fibroblasts ◽  
Arachidonic Acid Cascade ◽  
Cytosolic Phospholipase ◽  
Cox 2

Previously, we revealed that several kampo medicines that are used for patients with excess and/or medium patterns [kakkonto (TJ-1), shosaikoto (TJ-9), hangeshashinto (TJ-14), and orento (TJ-120)] reduced prostaglandin (PG)E<2 levels using LPS-treated human gingival fibroblasts (HGFs). Recently, we examined other kampo medicines used for patients with the deficiency pattern [bakumondoto (TJ-29), shinbuto (TJ-30), ninjinto (TJ-32), and hochuekkito (TJ-41)] and the herbs comprising shinbuto and ninjinto using the same experimental model. Shinbuto and ninjinto concentration-dependently reduced LPS-induced PGE2 production by HGFs, whereas hochuekkito weakly reduced and bakumondoto did not reduce PGE2 production. Shinbuto and ninjinto did not alter cyclooxygenase (COX) activity or the expression of molecules involved in the arachidonic acid cascade. Therefore, we next examined which herbs compromising shinbuto and ninjinto reduce LPS-induced PGE2 production. Among these herbs, shokyo (Zingiberis Rhizoma) and kankyo (Zingiberis Processum Rhizoma) strongly and concentration-dependently decreased LPS-induced PGE2 production. However, both shokyo and kankyo increased the expression of cytosolic phospholipase (cPL)A2 but did not affect annexin1 or COX-2 expression. These results suggest that shokyo and kankyo suppress cPLA2 activity. We demonstrated that kampo medicines suppress inflammatory responses in patients with the deficiency pattern, and in those with excess or medium patterns. Moreover, kampo medicines that contain shokyo or kankyo are considered to be effective for the treatment of inflammatory diseases.

scholarly journals GPR110 (ADGRF1) mediates anti-inflammatory effects of N-docosahexaenoylethanolamine

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Taeyeop Park ◽  
Huazhen Chen ◽  
Hee-Yong Kim
Keyword(s):  
Inflammatory Cytokine ◽  
Inflammatory Responses ◽  
Cytokine Expression ◽  
Regulatory Function ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inflammatory Condition ◽  
Wild Type ◽  
Knock Out ◽  
The Brain

Abstract Background Neuroinflammation is a widely accepted underlying condition for various pathological processes in the brain. In a recent study, synaptamide, an endogenous metabolite derived from docosahexaenoic acid (DHA, 22:6n-3), was identified as a specific ligand to orphan adhesion G-protein-coupled receptor 110 (GPR110, ADGRF1). Synaptamide has been shown to suppress lipopolysaccharide (LPS)-induced neuroinflammation in mice, but involvement of GPR110 in this process has not been established. In this study, we investigated the possible immune regulatory role of GPR110 in mediating the anti-neuroinflammatory effects of synaptamide under a systemic inflammatory condition. Methods For in vitro studies, we assessed the role of GPR110 in synaptamide effects on LPS-induced inflammatory responses in adult primary mouse microglia, immortalized murine microglial cells (BV2), primary neutrophil, and peritoneal macrophage by using quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA) as well as neutrophil migration and ROS production assays. To evaluate in vivo effects, wild-type (WT) and GPR110 knock-out (KO) mice were injected with LPS intraperitoneally (i.p.) or TNF intravenously (i.v.) followed by synaptamide (i.p.), and expression of proinflammatory mediators was measured by qPCR, ELISA, and western blot analysis. Activated microglia in the brain and NF-kB activation in cells were examined microscopically after immunostaining for Iba-1 and RelA, respectively. Results Intraperitoneal (i.p.) administration of LPS increased TNF and IL-1β in the blood and induced pro-inflammatory cytokine expression in the brain. Subsequent i.p. injection of the GPR110 ligand synaptamide significantly reduced LPS-induced inflammatory responses in wild-type (WT) but not in GPR110 knock-out (KO) mice. In cultured microglia, synaptamide increased cAMP and inhibited LPS-induced proinflammatory cytokine expression by inhibiting the translocation of NF-κB subunit RelA into the nucleus. These effects were abolished by blocking synaptamide binding to GPR110 using an N-terminal targeting antibody. GPR110 expression was found to be high in neutrophils and macrophages where synaptamide also caused a GPR110-dependent increase in cAMP and inhibition of LPS-induced pro-inflammatory mediator expression. Intravenous injection of TNF, a pro-inflammatory cytokine that increases in the circulation after LPS treatment, elicited inflammatory responses in the brain which were dampened by the subsequent injection (i.p.) of synaptamide in a GPR110-dependent manner. Conclusion Our study demonstrates the immune-regulatory function of GPR110 in both brain and periphery, collectively contributing to the anti-neuroinflammatory effects of synaptamide under a systemic inflammatory condition. We suggest GPR110 activation as a novel therapeutic strategy to ameliorate inflammation in the brain as well as periphery.

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