Abstract
Aims:
Data suggest pharmacological treatment of depression with selective serotonin reuptake inhibitors (SSRI) may impair bone health. Our group has previously modeled compromised craniofacial healing after treatment with sertraline, a commonly prescribed SSRI, and hypothesized potential culprits: alterations in bone cells, collagen, and/or inflammation. Here we interrogate bone lineage cell alterations due to sertraline treatment as a potential cause of the noted compromised bone healing.
Main methods:
Murine pre-osteoblast, pre-osteoclast, osteoblast, and osteoclast cells were treated with clinically relevant concentrations of the SSRI. Studies focused on serotonin pathway targets, cell viability, apoptosis, differentiation, and the osteoblast/osteoclast feedback loop.
Key findings:
All cells studied express neurotransmitters (e.g. serotonin transporter, SLC6A4, SSRI target) and G-protein-coupled receptors associated with the serotonin pathway. Osteoclasts presented the greatest native expression of Slc6a4 with all cell types exhibiting decreases in Slc6a4 expression after SSRI treatment. Pre-osteoclasts exhibited alteration to their differentiation pathway after treatment. Pre-osteoblasts and osteoclasts showed reduced apoptosis after treatment but showed no significant differences in functional assays.
Rankl:
OPG mRNA and protein ratios were decreased in the osteoblast lineage. Osteoclast lineage cells treated with sertraline demonstrated diminished TRAP positive cells when pre-exposed to sertraline prior to RANKL-induced differentiation.
Significance:
These data suggest osteoclasts are a likely target of bone homeostasis disruption due to sertraline treatment, most potently through the osteoblast/clast feedback loop.
Keywords:
Osteoblast; Osteoclast; SLC6A4; SSRI.