Objective: The goal of this study was to investigate RvD1 receptor expression and signaling pathways in primary salivary cells.
Method: Submandibular glands (mSMG) were extracted from adult female C57BL/6 mice. Western blot analyses were used to detect phosphorylated Erk1/2 and Akt expression in mSMG. Histological sections (10 µm) of mSMG and human minor salivary glands (hMSG) were prepared and stained for RvD1 receptor expression.
Result: Our results indicate that the RvD1 receptor ALX/FPR2 is expressed in mSMG and is able to elicit intracellular calcium responses and phosphorylation of Erk1/2 and Akt. Given that these signaling pathways are linked to cell survival, we investigated whether AT-RvD1 was able to prevent programmed cell death in mSMG. Specifically, we determined that AT-RvD1 prevented TNF-α-mediated caspase-3 activation. Finally, we show that the ALX/FPR2 receptor is expressed in hMSG with and without SS, indicating the potential therapeutic use of AT-RvD1 for this condition.
Conclusion: The AT-RvD1 receptor is expressed in primary salivary cells and is able to increase a diverse set of intracellular signaling pathways such as calcium, Erk1/2 and Akt. Additionally, we were able to demonstrate that AT-RvD1 blocks TNF-α-mediated caspase-3 activation in mSMG. The expression of the ALX/FPR2 receptor seems to be unaltered in hMSG with and without SS, indicating that RvD1 could be used as a therapeutic option to treat salivary gland inflammation in SS patients.