Lysophosphatidic Acid signals through specific lysophosphatidic Acid receptor subtypes to control key regenerative responses of human gingival and periodontal ligament fibroblasts.
BACKGROUND
We showed that the pluripotent platelet growth factor and mediator lysophosphatidic acid (LPA) controls key regenerative responses of human gingival fibroblasts (GFs) and periodontal ligament fibroblasts (PDLFs) and positively modulates their responses to platelet-derived growth factor (PDGF). This study determined which LPA receptor (LPAR) subtype(s) LPA signals through to stimulate mitogenic extracellular signal-regulated kinase (ERK) 1/2 signaling and chemotaxis and to elicit intracellular Ca(2+) increases in GFs and PDLFs because many healing responses are calcium-dependent.


METHODS
Activation of mitogen-activated protein kinase was determined using Western blotting with an antibody to phosphorylated ERK1/2. Migration responses were measured using a microchemotaxis chamber. GF and PDLF intracellular Ca(2+) mobilization responses to multiple LPA species and LPAR subtype-specific agonists were measured by using a cell-permeable fluorescent Ca(2+) indicator dye.


RESULTS
LPA stimulated ERK1/2 phosphorylation via LPA(1)(-3). For GFs, LPA(1) preferentially elicited chemotaxis, and LPA(1-3) for PDLFs, as confirmed using subtype-specific agonists. Elevation of intracellular calcium seems to be mediated through LPA(1) and LPA(3), with little, if any, contribution from LPA(2).


CONCLUSIONS
To the best of our knowledge, this study provides the first evidence that LPA signals through specific LPAR subtypes to stimulate human oral fibroblast regenerative responses. These data, in conjunction with our previous findings showing that LPA modulates GF and PDLF responses to PDGF, suggest that LPA is a factor of emerging importance to oral wound healing.
George
Joju
J
Department of Pharmacology, Creighton University School of Medicine, Omaha, NE, USA.
Headen
Karmel V
KV
Ogunleye
Afolabi O
AO
Perry
Greg A
GA
Wilwerding
Terrence M
TM
Parrish
Lawrence C
LC
McVaney
Timothy P
TP
Mattson
John S
JS
Cerutis
D Roselyn
DR
D000328:Adult; D015153:Blotting, Western; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects / Q000502:physiology; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology; D005456:Fluorescent Dyes; D005881:Gingiva / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007555:Isoxazoles / Q000494:pharmacology; D008246:Lysophospholipids / Q000494:pharmacology / Q000502:physiology*; D008297:Male; D019950:Mitogen-Activated Protein Kinase 1 / Q000187:drug effects / Q000502:physiology; D048052:Mitogen-Activated Protein Kinase 3 / Q000187:drug effects / Q000502:physiology; D063086:Organothiophosphates / Q000494:pharmacology; D010513:Periodontal Ligament / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D010712:Phosphatidic Acids / Q000494:pharmacology; D010766:Phosphorylation; D011422:Propionates / Q000494:pharmacology; D049368:Receptors, Lysophosphatidic Acid / Q000819:agonists / Q000037:antagonists & inhibitors / Q000145:classification*; D012038:Regeneration / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D014945:Wound Healing / Q000187:drug effects / Q000502:physiology; D055815:Young Adult
C473891:1-oleoyl-2-O-methyl-rac-glycerophosphothionate; C477898:3-(4-(4-((1-(2-chlorophenyl)ethoxy)carbonyl amino)-3-methyl-5-isoxazolyl) benzylsulfanyl) propanoic acid; D005456:Fluorescent Dyes; D007555:Isoxazoles; D008246:Lysophospholipids; D063086:Organothiophosphates; D010712:Phosphatidic Acids; D011422:Propionates; D049368:Receptors, Lysophosphatidic Acid; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; C032881:lysophosphatidic acid