P2Y2 nucleotide receptor activation enhances the aggregation and self-organization of dispersed salivary epithelial cells.
Hyposalivation resulting from salivary gland dysfunction leads to poor oral health and greatly reduces the quality of life of patients. Current treatments for hyposalivation are limited. However, regenerative medicine to replace dysfunctional salivary glands represents a revolutionary approach. The ability of dispersed salivary epithelial cells or salivary gland-derived progenitor cells to self-organize into acinar-like spheres or branching structures that mimic the native tissue holds promise for cell-based reconstitution of a functional salivary gland. However, the mechanisms involved in salivary epithelial cell aggregation and tissue reconstitution are not fully understood. This study investigated the role of the P2Y2 nucleotide receptor (P2Y2R), a G protein-coupled receptor that is upregulated following salivary gland damage and disease, in salivary gland reconstitution. In vitro results with the rat parotid acinar Par-C10 cell line indicate that P2Y2R activation with the selective agonist UTP enhances the self-organization of dispersed salivary epithelial cells into acinar-like spheres. Other results indicate that the P2Y2R-mediated response is dependent on epidermal growth factor receptor activation via the metalloproteases ADAM10/ADAM17 or the α5β1 integrin/Cdc42 signaling pathway, which leads to activation of the MAPKs JNK and ERK1/2. Ex vivo data using primary submandibular gland cells from wild-type and P2Y2R(-/-) mice confirmed that UTP-induced migratory responses required for acinar cell self-organization are mediated by the P2Y2R. Overall, this study suggests that the P2Y2R is a promising target for salivary gland reconstitution and identifies the involvement of two novel components of the P2Y2R signaling cascade in salivary epithelial cells, the α5β1 integrin and the Rho GTPase Cdc42.
Department of Biochemistry, University of Missouri, Columbia, Missouri; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri.
Farid G
FG
El-Sayed
Department of Biochemistry, University of Missouri, Columbia, Missouri; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri.
Jean M
JM
Camden
Department of Biochemistry, University of Missouri, Columbia, Missouri; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri.
Lucas T
LT
Woods
Department of Biochemistry, University of Missouri, Columbia, Missouri; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri.
Mahmoud G
MG
Khalafalla
Department of Biochemistry, University of Missouri, Columbia, Missouri; Department of Nutritional Sciences and Exercise Physiology, University of Missouri, Columbia, Missouri; and Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri.
Michael J
MJ
Petris
Department of Biochemistry, University of Missouri, Columbia, Missouri; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri.
Laurie
L
Erb
Department of Biochemistry, University of Missouri, Columbia, Missouri; Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, Missouri weismang@missouri.edu.
Gary A
GA
Weisman
D051722:ADAM Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D000072197:ADAM10 Protein; D000072198:ADAM17 Protein; D000818:Animals; D002449:Cell Aggregation / Q000187:drug effects*; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects*; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D006801:Humans; D039081:Integrin alpha5beta1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010306:Parotid Gland / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010766:Phosphorylation; D011480:Protease Inhibitors / Q000494:pharmacology; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D058912:Purinergic P2Y Receptor Agonists / Q000494:pharmacology*; D051381:Rats; D058473:Receptors, Purinergic P2Y2 / Q000172:deficiency / Q000187:drug effects* / Q000235:genetics; D013363:Submandibular Gland / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D014162:Transfection; D014544:Uridine Triphosphate / Q000494:pharmacology*; D020764:cdc42 GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000378:metabolism
D039081:Integrin alpha5beta1; D011480:Protease Inhibitors; D047428:Protein Kinase Inhibitors; D058912:Purinergic P2Y Receptor Agonists; D058473:Receptors, Purinergic P2Y2; C483803:Egfr protein, rat; D066246:ErbB Receptors; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D051722:ADAM Proteins; D000072197:ADAM10 Protein; C542371:ADAM10 protein, rat; D000072198:ADAM17 Protein; C000606462:ADAM17 protein, human; C000606463:Adam17 protein, mouse; C000606464:Adam17 protein, rat; D020764:cdc42 GTP-Binding Protein; D014544:Uridine Triphosphate
Cdc42 Rho GTPase; EGF receptor; P2Y2 nucleotide receptor; extracellular ATP; salivary gland reconstitution; α5β1 integrin