Kinases in Neutrophils Activation of the P21-Activated Protein Products
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Products of Sphingolipid Catabolism Block Activation of the p21-Activated Protein Kinases in Neutrophils This information is current as Jian P. Lian, RiYun Huang, Dwight Robinson and John A. of September 23, 2021. Badwey J Immunol 1998; 161:4375-4381; ; http://www.jimmunol.org/content/161/8/4375 Downloaded from References This article cites 57 articles, 35 of which you can access for free at: http://www.jimmunol.org/content/161/8/4375.full#ref-list-1 Why The JI? Submit online. http://www.jimmunol.org/ • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average by guest on September 23, 2021 Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 1998 by The American Association of Immunologists All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. Products of Sphingolipid Catabolism Block Activation of the p21-Activated Protein Kinases in Neutrophils1 Jian P. Lian,* RiYun Huang,† Dwight Robinson,† and John A. Badwey2*‡ Neutrophils stimulated with the chemoatttractant FMLP are known to exhibit a rapid and transient activation of two p21- activated protein kinases (Paks) with molecular masses of approximately 63 and 69 kDa. Paks can be detected by their ability to undergo renaturation and catalyze the phosphorylation of a peptide substrate that corresponds to amino acid residues 297 to 331 of the 47-kDa subunit of the nicotinamide-adenine dinucleotide phosphate-oxidase complex (p47-phox) fixed within a gel. In this study, we demonstrate that N-acetylsphingosine (C2-ceramide) and a variety of sphingoid bases (e.g., D-erythrosphingosine) block activation of the 63- and 69-kDa Paks in neutrophils. The concentrations of these lipids that were effective in blocking Pak activation were similar to those that inhibit a variety of neutrophil responses. Activation of the 63- and 69-kDa Paks was also markedly reduced in neutrophils treated with sphingomyelinase before stimulation. Moreover, we report that addition of C2- ceramide or D-erythrosphingosine to neutrophils after stimulation with FMLP markedly enhances the rate of Pak inactivation. Downloaded from These effects were not mimicked by arachidonate, which is a potent disorganizing agent of neutrophil membranes. These data support and extend the proposal that sphingoid bases may establish a set point in neutrophils for positive stimuli. The Journal of Immunology, 1998, 161: 4375–4381. eutrophils stimulated with the chemoattractant FMLP ex- A variety of studies over the past decade strongly suggest that hibit a rapid and transient activation of four renaturable certain sphingolipids may function as second messengers or mod- http://www.jimmunol.org/ N protein kinases with molecular masses of approximately ulators of cellular responses (e.g., for review, see Refs. 21–23). 69, 63, 49, and 40 kDa (1–3). Activation of all four of these kinases Cell-permeable derivatives of ceramide (C2-ceramide) and sphin- appears to be under the control of a single stimulatory pathway that is goid bases (e.g., D-erythrosphingosine) inhibit phagocytosis, de- 2 sensitive to antagonists of heterotrimeric G proteins, type 1 and/or 2A granulation, and O2 production by neutrophils (17, 24–28). Inter- protein phosphatases, tyrosine kinases, and phosphatidylinositol 3-ki- estingly, C2-ceramide also inhibits activation of ERK1 and ERK2 nase (1–6). The 63- and 69-kDa enzymes were subsequently identi- in neutrophils (17) and blocks translocation of certain small GT- fied as p21-activated kinases (Paks)3 (7, 8). Paks undergo autophos- Pases (Cdc42) to the membrane of these cells (29). Sphingoid phorylation/activation upon binding the active (GTP-bound) forms of bases inhibit PKC (25) and phosphatidic acid phosphatase in neu- the small GTPases (p21) Rac or Cdc42 (9). Paks can catalyze the trophils (30). Increased amounts of ceramide and sphingosine have by guest on September 23, 2021 phosphorylation of the 47-kDa subunit of the nicotinamide-adenine been observed in FMLP-stimulated neutrophils and neutrophils dinucleotide phosphate-oxidase complex (p47-phox) (7) and certain undergoing IgG-dependent phagocytosis (17, 28, 31). The cellular heavy and light chains of myosin (e.g., 10, 11). Paks are also involved concentrations of these lipids also undergo marked increases in in the activation/potentiation of several distinct MAP kinase cascades. certain genetic diseases (e.g., Farber’s lipogranulomatosis) and Transfection of constitutively active Pak or overexpression of wild- during various infections (e.g., Refs. 32–34). type Pak in certain cells is sufficient to activate the c-jun N-terminal Paks and Pak-related kinases may be regulated by various lipids kinase/stress-activated protein kinase (JNK/SAPK) and, to a lesser (35, 36). In particular, a recent study has demonstrated that high extent, p38 MAP kinase (e.g., 12–14; for review, see Ref. 15). More- concentrations of sphingoid bases (50–200 mM) and certain other over, activated Pak can potentiate the ability of wild-type Raf-1 or lipids can activate Pak 1 in vitro in a manner similar to that ob- growth factors to stimulate ERKs and MAP-kinase kinases in numer- served with Cdc42-GTP (36). COS-7 cells expressing Pak 1 ex- ous cell types (14, 16). Selective antagonists of MAP-kinase kinase hibit enhanced activity of this kinase when treated with agents that and p38 MAP kinase inhibit chemotaxis, phagocytosis, degranulation, elevate the content of sphingosine (36). T cells also exhibit an and superoxide production by neutrophils (17–20). Thus, Paks may enhanced activity of Pak when treated with C2-ceramide through participate in a variety of neutrophil responses. an unknown mechanism (37). In this study, we report that products of sphingolipid catabolism block activation of the 63- and 69-kDa Paks in FMLP-stimulated neutrophils. The effective concentrations †Arthritis Unit, Massachusetts General Hospital, Boston, MA 02114; ‡Department of of these lipids are in the range of those that can be achieved under Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Bos- ton, MA 02115; and *Boston Biomedical Research Institute, Boston, MA 02114 various physiologic/pathologic situations. The significance of Received for publication March 24, 1998. Accepted for publication June 22, 1998. these results to neutrophil function and Pak activation under var- ious circumstances is discussed. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. 1 These studies were supported by National Institutes of Health Grants DK 50015, AI Materials and Methods 23323 (to J.A.B.), and AR 43518 (to D.R.). Materials 2 Address correspondence and reprint requests to Dr. John A. Badwey, Boston Bio- medical Research Institute, 20 Staniford St., Boston, MA 02114. D-Erythro-C2-ceramide (N-acetylsphingosine), D-erythrodihydro-C2-cer- 3 Abbreviations used in this paper: Pak, p21-activated protein kinase; ERK, extracel- amide (N-acetyldihydrosphingosine), D-erythrosphingosine, D-erythrodihy- lular-regulated kinase; MAP, mitogen-activated protein; p47-phox, the 47-kDa pro- drosphingosine, and sphingosine-1-phosphate were purchased from Cal- tein component of the phagocyte oxidase; PKC, protein kinase C. biochem (La Jolla, CA). D,L-threodihydrosphingosine was obtained from Copyright © 1998 by The American Association of Immunologists 0022-1767/98/$02.00 4376 SPHINGOLIPIDS AND p21-ACTIVATED PROTEIN KINASES FIGURE 1. Effects of C2-ceramides on the activation of the 63- and 69-kDa Paks in neutrophils. The renaturable protein kinases in neutrophils FIGURE 2. Effects of various sphingoid bases on the activation of the 63- and 69-kDa Paks in neutrophils. Autoradiographs demonstrate the ef- were assayed directly in gels containing the fixed peptide substrate, as Downloaded from referenced under Materials and Methods. A, Cells were incubated in the fects of D-erythrosphingosine (A), D,L-threodihydrosphingosine (B), and m D-erythrodihydrosphingosine (C) on the activation of the 63- and 69-kDa absence (lanes a and b) and presence of 40 MC2-ceramide (lanes c and m Paks in neutrophils. Intact cells were treated with: lane a, 0.25% (v/v) d)or40 MC2-dihydroceramide (lanes e and f) for 5 min prior to treat- ment for 15 s with 0.25% (v/v) DMSO (lanes a, c, and e; unstimulated DMSO for 5 min, followed by an additional 0.25% (v/v) DMSO for 15 s cells) or 1 mM FMLP (lanes b, d, and f; stimulated cells). B, Shows the (unstimulated cells); lane b, 0.25% (v/v) DMSO for 5 min, followed by 1 complete profile for the renaturable kinases from the same experiment, mM FMLP for 15 s; and lane c,10mM sphingoid base for 5 min, followed m except the time of development of the autoradiograph was increased from by 1 M FMLP for 15 s. The concentrations of sphingoid bases utilized in http://www.jimmunol.org/ these studies did not affect cell viability, as measured by the exclusion of 18 to 72 h. The concentrations of C2-ceramide and C2-dihydroceramide utilized in these studies did not affect cell viability, as measured by the trypan blue. Paks were monitored after renaturation by their ability to cat- exclusion of trypan blue. The positions of the 63- and 40-kDa kinases are alyze the phosphorylation of the p47-phox peptide fixed within a gel, as designated by unbroken arrows, whereas the 69- and 49-kDa kinases are described in Materials and Methods.