Stem cells from tooth apical papilla modulate fibromyalgia-like changes in mice

The treatment of fibromyalgia remains a current challenge. While the analgesic effects of mesenchymal stem cells have been the subject of previous research, their potential in managing fibromyalgia symptoms needs further investigation. In this study, we investigated the effects of human stem cells from tooth apical papilla (SCAP), when administered systemically, in a mouse model of fibromyalgia induced by reserpine. The effects of repeated intraperitoneal (i.p.) treatment with SCAP were evaluated in the mouse model of fibromyalgia induced by reserpine, by assessing behavioral and biochemical parameters. The systemic treatment with SCAP significantly reduced the mechanical and thermal hypersensitivity induced by reserpine in mice. Moreover, the SCAP treatment also reversed depression-like behavior, as assessed in the forced swimming test (FST). The SCAP administration partly restored the reduction in the total number of entries in the elevated plus maze but failed to alter the fatigue intensity or the grip strength. The treatment with SCAP significantly increased dopamine, glutamate, and glutathione levels in the masseter muscle compared to the vehicle-treated control animals. Conversely, the SCAP administration decreased the glutathione levels in the prefrontal cortex and spinal cord compared to the control mice. Finally, the repeated treatment with SCAP led to a significant increase in the spinal cord levels of the chemokine CXCL1/KC. Our research findings offer new insights into the efficacy of human SCAP in a pre-clinical model of fibromyalgia, likely through the modulation of both peripheral and central mechanisms.