minocycline enhance the restorative ability of olfactory ensheathing cells by the upregulation of bdnf and gdnf expression after spinal cord injury

Introduction: spinal cord injury (sci) is a global public health issue that results in extensiveneuronal degeneration, axonal and myelin loss, and severe functional deficits. neurotrophicfactors are a potential treatment for reducing secondary damage, promoting axon growth; theyare responsible for inducing myelination after injury. olfactory ensheathing cells (oecs) andminocycline have promoted locomotor function after sci. the present study investigated theneuroprotective effects of combined treatment with minocycline and oecs on spinal cordinjury related to brain-derived neurotrophic factor (bdnf) and glial derived neurotrophicfactor (gdnf) expressions after sci.methods: adult female rats were used to experimental sci by weight compression method.rats received an intraperitoneal minocycline injection (90 mg/kg) immediately after sci and24 h after injury. oecs were transplanted one week after the injury. the hindlimb function wasassessed using basso beattie bresnahan (bbb) locomotor rating scale and electromyography(emg). after 5 weeks, the spinal cord segment centered at the injury site was removed forhistopathological analysis. immunohistological and western blot assays were performed toobserve the expression of neun, bdnf, gdnf, and myelin basic protein (mbp).results: sci induced the loss of locomotor function with decreased bdnf and gdnfexpressions in the injury site. minocycline+oecs increased the score of the bbb locomotorscale and increased spared tissue in the injury site. immunohistochemical results suggestedthat neun expression significantly increased in the minocycline+oecs group than othergroups. moreover, electromyography amplitude in treated rats was increased compared to thecontrol group. bdnf, gdnf, and mbp expressions and the number of ventral motor neuronsincreased further by minocycline+oecs in sci rats.conclusion: the present study provides evidence that minocycline may facilitate recoveryof locomotor function by oecs by increasing bdnf and gdnf expressions following sci.