Human placental extract attenuates neurological symptoms in the experimental autoimmune encephalomyelitis model of multiple sclerosis-a putative approach in MS disease?

BACKGROUND: Different studies have demonstrated the anti-inflammatory effects of human placental extract both in vivo and in vitro. Considering the chronic inflammatory nature of multiple sclerosis (MS) disease, we examined whether or not the administration of human placental extract is able to attenuate the neurological symptoms detected in experimental autoimmune encephalomyelitis (EAE) model of MS. METHODS: The injected myelin oligodendrocyte glycoprotein (MOG) induced EAE in mice, and treatment began from day 4 post-injection by intraperitoneal administration of 0.2 mg/kg human placental extract, repeated every other day up to day 31 post-injection. At the end of the treatment, luxol fast blue (LBS) staining and hematoxylin and eosin (H&E) staining were performed to evaluate the demyelination of neurons and inflammatory responses, respectively. Further assessed were the serum concentrations of IL-23 and IL-27. RESULTS: The administration of human placental extract was able to significantly reduce the mean clinical score in EAE mice, decrease the pro-inflammatory process and attenuate neural demyelination. Moreover, while the serum concentration of IL-23 was significantly diminished in the EAE mice receiving human placental extract compared to the non-treated EAE group, IL-27 concentration was significantly increased. CONCLUSIONS: Our findings demonstrated the administration of human placental extract could significantly attenuate the neurological symptoms in the EAE model of MS in part through modulating the serum levels of IL-23 and IL-27 and enhancing neuroprotection and myelin repair.