Forensic Medicine and Clinical Toxicology Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
Medical Experimental Research Center, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
Mol Med Rep. 2019 Apr;19(4):2611-2619. doi: 10.3892/mmr.2019.9924. Epub 2019 Feb 1.
Selective serotonin reuptake inhibitors are the most commonly prescribed antidepressants worldwide, which have been reported to exert potential detrimental effects on bone mineral density and increase the risk of developing fractures. The present study aimed to investigate the pathways underlying the negative effects of fluoxetine on bone using mesenchymal stem cells (MSCs) derived from rat adipose tissue as a source of osteoprogenitor cells. MSCs were harvested from adipose tissue using a collagenase enzyme digestion method and were allowed to differentiate into osteoprogenitor cells. Various concentrations of fluoxetine were added to the cells, which were harvested and analyzed by flow cytometry to detect apoptotic markers Annexin V and caspase‑3, in order to assess the levels of apoptosis. The levels of endogenous serotonin released in the extracellular matrix were measured using a serotonin ELISA kit. The underlying molecular pathways associated with the effects of fluoxetine on bone were investigated with reverse transcription‑quantitative polymerase chain reaction. The results of the present study revealed a significant dose‑dependent increase in apoptosis in response to increasing doses of fluoxetine, which was independent of serotonin levels in the culture supernatant. These findings indicated that fluoxetine exerted a direct inhibitory effect on bone cells via an apoptosis‑dependent pathway. Furthermore, the expression levels of serotonergic genes, including serotonin 1B receptor, serotonin 2A receptor (HTR2A), serotonin 2B receptor and serotonin transporter, were down regulated; of these genes, HTR2A exhibited the highest expression levels. Further in vitro and in vivo studies are required to verify this association and to determine the molecular pathways involved in fluoxetine‑induced bone loss. Fluoxetine‑induced apoptosis of osteoprogenitor cells may be the mechanism underlying the increased incidence of bone loss observed in patients treated with fluoxetine.
选择性 5-羟色胺再摄取抑制剂是全球最常开的抗抑郁药，据报道，它们会对骨密度产生潜在的有害影响，并增加骨折的风险。本研究旨在使用源自大鼠脂肪组织的间充质干细胞（MSC）作为成骨祖细胞的来源，研究氟西汀对骨产生负面影响的途径。使用胶原酶消化法从脂肪组织中提取 MSC，并允许其分化为成骨祖细胞。将不同浓度的氟西汀添加到细胞中，然后通过流式细胞术收集和分析细胞，以检测凋亡标志物 Annexin V 和 caspase-3，从而评估细胞凋亡水平。使用 5-羟色胺 ELISA 试剂盒测量细胞外基质中释放的内源性 5-羟色胺水平。使用逆转录定量聚合酶链反应（RT-qPCR）研究与氟西汀对骨的影响相关的潜在分子途径。本研究的结果表明，随着氟西汀剂量的增加，细胞凋亡呈显著的剂量依赖性增加，这与培养上清液中的 5-羟色胺水平无关。这些发现表明，氟西汀通过依赖于凋亡的途径对成骨细胞发挥直接抑制作用。此外，包括 5-羟色胺 1B 受体、5-羟色胺 2A 受体（HTR2A）、5-羟色胺 2B 受体和 5-羟色胺转运体在内的 5-羟色胺能基因的表达水平下调；其中 HTR2A 的表达水平最高。需要进一步的体外和体内研究来验证这种关联，并确定涉及氟西汀诱导骨丢失的分子途径。氟西汀诱导成骨祖细胞凋亡可能是氟西汀治疗患者骨丢失发生率增加的机制。
