PMID- 28509344
OWN - NLM
STAT- MEDLINE
DCOM- 20180501
LR  - 20230829
IS  - 1538-7836 (Electronic)
IS  - 1538-7836 (Linking)
VI  - 15
IP  - 8
DP  - 2017 Aug
TI  - cGMP signaling inhibits platelet shape change through regulation of the RhoA-Rho 
      Kinase-MLC phosphatase signaling pathway.
PG  - 1668-1678
LID - 10.1111/jth.13738 [doi]
AB  - Essentials Platelet shape change requires cytoskeletal rearrangement via 
      myosin-mediated actin contraction. We investigated whether nitric oxide (NO) 
      affected thrombin-induced platelet shape change. NO inhibits shape change, 
      RhoA/ROCK signalling and myosin light chain (MLC) phosphorylation. NO promotes 
      MLC phosphatase activity, thus prevents MLC phosphorylation and shape change. 
      SUMMARY: Background Platelet shape change, spreading and thrombus stability 
      require activation of the actin cytoskeleton contractile machinery. The 
      mechanisms controlling actin assembly to prevent unwanted platelet activation are 
      unclear. Objectives We examined the effects of nitric oxide on the signaling 
      pathways regulating platelet actin-myosin activation. Results 
      S-nitrosoglutathione (GSNO) inhibited thrombin-induced platelet shape change and 
      myosin phosphorylation of the myosin light chain (MLC). Because thrombin 
      stimulates phospho-MLC through the RhoA/ ROCK dependent inhibition of MLC 
      phosphatase (MLCP) we examined the effects of NO on this pathway. Thrombin caused 
      the GTP loading and activation of RhoA, leading to the ROCK-mediated 
      phosphorylation of MLCP on threonine 853 (thr(853) ), which is known to inhibit 
      phosphatase activity. Treatment of platelets with GSNO blocked ROCK-mediated 
      increases in phosphoMLCP-thr(853) induced by thrombin. This effect was mimicked 
      by the direct activator of protein kinase G, 8-pCPT-PET-cGMP, and blocked by the 
      inhibition of guanylyl cyclase, but not inhibitors of protein kinase A. Further 
      exploration of the mechanism demonstrated that GSNO stimulated the association of 
      RhoA with protein kinase G (PKG) and the inhibitory phosphorylation (serine188) 
      of RhoA in a cGMP-dependent manner. Consistent with these observations, in vitro 
      experiments revealed that recombinant PKG caused direct phosphorylation of RhoA. 
      The inhibition of RhoA by GSNO prevented ROCK-mediated phosphorylation and 
      inhibition of MLCP activity. Conclusions These data suggest novel crosstalk 
      between the NO-cGMP-PKG and RhoA/ROCK signaling pathways to control platelet 
      actin remodeling.
CI  - (c) 2017 The Authors. Journal of Thrombosis and Haemostasis published by Wiley 
      Periodicals, Inc. on behalf of International Society on Thrombosis and 
      Haemostasis.
FAU - Aburima, A
AU  - Aburima A
AD  - Centre for Cardiovascular and Metabolic Research, Hull York Medical School, 
      University of Hull, Hull, UK.
FAU - Walladbegi, K
AU  - Walladbegi K
AD  - Centre for Cardiovascular and Metabolic Research, Hull York Medical School, 
      University of Hull, Hull, UK.
FAU - Wake, J D
AU  - Wake JD
AD  - Centre for Cardiovascular and Metabolic Research, Hull York Medical School, 
      University of Hull, Hull, UK.
FAU - Naseem, K M
AU  - Naseem KM
AD  - Centre for Cardiovascular and Metabolic Research, Hull York Medical School, 
      University of Hull, Hull, UK.
LA  - eng
GR  - PG/10/90/28636/BHF_/British Heart Foundation/United Kingdom
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20170718
PL  - England
TA  - J Thromb Haemost
JT  - Journal of thrombosis and haemostasis : JTH
JID - 101170508
RN  - 0 (Myosin Light Chains)
RN  - 0 (Nitric Oxide Donors)
RN  - 124671-05-2 (RHOA protein, human)
RN  - 31C4KY9ESH (Nitric Oxide)
RN  - 57564-91-7 (S-Nitrosoglutathione)
RN  - EC 2.7.11.1 (rho-Associated Kinases)
RN  - EC 2.7.11.12 (Cyclic GMP-Dependent Protein Kinases)
RN  - EC 3.1.3.53 (Myosin-Light-Chain Phosphatase)
RN  - EC 3.1.3.53 (PPP1R12A protein, human)
RN  - EC 3.4.21.5 (Thrombin)
RN  - EC 3.6.5.2 (rhoA GTP-Binding Protein)
RN  - H2D2X058MU (Cyclic GMP)
SB  - IM
MH  - Blood Platelets/drug effects/*enzymology
MH  - *Cell Shape/drug effects
MH  - Cyclic GMP/*metabolism
MH  - Cyclic GMP-Dependent Protein Kinases/metabolism
MH  - Cytoskeleton/drug effects/*enzymology
MH  - Humans
MH  - Myosin Light Chains/metabolism
MH  - Myosin-Light-Chain Phosphatase/*metabolism
MH  - Nitric Oxide/metabolism
MH  - Nitric Oxide Donors/metabolism/pharmacology
MH  - Phosphorylation
MH  - *Platelet Activation/drug effects
MH  - S-Nitrosoglutathione/metabolism/pharmacology
MH  - *Second Messenger Systems/drug effects
MH  - Thrombin/pharmacology
MH  - Time Factors
MH  - rho-Associated Kinases/*metabolism
MH  - rhoA GTP-Binding Protein/*metabolism
OTO - NOTNLM
OT  - RhoA GTP-biding protein
OT  - cyclic GMP
OT  - myosin light chain phosphatase
OT  - nitric oxide
OT  - platelets
OT  - protein kinase A
EDAT- 2017/05/17 06:00
MHDA- 2018/05/02 06:00
CRDT- 2017/05/17 06:00
PHST- 2016/11/30 00:00 [received]
PHST- 2017/05/17 06:00 [pubmed]
PHST- 2018/05/02 06:00 [medline]
PHST- 2017/05/17 06:00 [entrez]
AID - S1538-7836(22)04327-6 [pii]
AID - 10.1111/jth.13738 [doi]
PST - ppublish
SO  - J Thromb Haemost. 2017 Aug;15(8):1668-1678. doi: 10.1111/jth.13738. Epub 2017 Jul 
      18.