Royal jelly can diminish secondary neuronal damage after experimental spinal cord injury in rabbits

The aim of this experimental study was to investigate the neuroprotective effect of Royal jelly (RJ) on traumatic spinal cord injury (SCI). Twenty-one New Zealand male rabbits, weighing between 2.5 and 3.0 kg were divided into three groups: Sham (no drug or operation, n = 7), Control (laminectomy + single dose of 1 ml/kg saline orally, after trauma; n = 7) and RJ (laminectomy + 100 mg/kg RJ, orally, after trauma, n = 7). Laminectomy was performed at T10 and balloon catheter was applied extradurally for traumatic SCI. Four and 24 h after surgery, rabbits were evaluated according to the Tarlov scoring system. Blood, cerebrospinal fluid and tissue sample from spinal cord were taken for measurements of antioxidant status or detection of apoptosis. Four hours after SCI, all animals in control or RJ treated groups became paraparesic. Significant improvement was observed in RJ treated group, 24 h after SCI, with respect to control. Traumatic SCI led to increase in the lipid peroxidation and decrease enzymic or non-enzymic endogenous antioxidative defense systems, and increase in apoptotic cell numbers. RJ treatment mostly prevented lipid peroxidation and also augmented endogenous enzymic or non-enzymic antioxidative defense systems. Again, RJ treatment significantly decreased the apoptotic cell number induced by SCI.