Effect of Mesenchymal Stem Cells’ Conditioned Medium on the Expression of CCL3 and CCL4 Chemokines in the Spinal Cord of Rats with Neuropathic Pain

Background and

Inflammation plays an important role in the development of neuropathic pain (NP). Considering the anti-inflammatory effects of mesenchymal stem cells (MSCs) and their conditioned medium (CM), we aimed to investigate the effect of MSC-CM on the expression of CCL3 and CCL4 genes in the spinal cord of rats with NP.

In this experimental-interventional study, 28 male Wistar rats weighing 200-300 grams were included. NP was induced in male rats using the chronic constriction injury (CCI) model of the sciatic nerve. MSCs-CM was injected intraperitoneally (1ml) into each rat in the experimental group one day before surgery (-1), and 7 and 11 days after the surgery, while the rats of control group received DMEM. At the end of the study (day 15), the expression level of CCL3 and CCL4 genes in the animals’ spinal cord was measured using Real time PCR.

Molecular studies showed a significant decrease in CCL3 gene expression (P<0.05) in CM treated animals compared to the control group, but in term of CCL4 gene expression, there was no significant difference between the groups.

Anti-NP effects of MSCs-CM seem to be partly mediated through downregulation of CCL3 chemokine in the spinal cord.