Research of Magnetic Liposomes Crossing Blood Spinal Cord Barrier after Spinal Cord Injury in Rats
|School||Tianjin Medical University|
|Keywords||Blood - spinal cord barrier Magnetic nano- liposomes Spinal cord injury Tail vein injection Rats|
The magnetic nano-liposomes as a drug carrier, after injection via the tail vein across the blood spinal barrier in rats with spinal cord injury, partial aggregation and dispersion was observed in the spinal cord injury in vivo safety and biocompatibility. A novel magnetic nano-liposomes, in accordance with the preparation concentration of 48 adult Wistar rats were randomly divided into four groups: high concentration 7.5 mg, in concentrations of 3.25mg/ml, low concentration group 1.625mg/ml and the control group. Prepared magnetic nano-liposomes in accordance with the prescribed dose (as 100mg/kg, 50mg/kg, 25mg/kg) were injected rats in the control group injected with saline in the same way, observed after injection 7d rats general changes by HE staining, Prussian blue staining of magnetic nanoliposomes rat organ toxicity. Prepared by reverse evaporation method new magnetic nanoliposomes, connected to the surface functional groups TAT ??(transactivator protein), PEG (polyethylene glycol) and the formation of TAT-PEG-magnetic nano-liposomes, to make it both transmembrane long circulatory function and magnetic resonance imaging in vivo tracking function; 36 adult Wistar rats Impactor Model-II method establish T10 acute spinal cord injury model, were randomly divided into three groups, group A: PEG-magnetic nano-liposome group, B group : TAT-PEG-magnetic nano-liposome group and a control group, 12 in each group. TAT-PEG-magnetic nano-liposomes were prepared by tail vein injection group B spinal cord injury model in vivo (dose: 4.55mg/kg, 1 times / day × 3), PEG-magnetic nano-liposomes Group A at the same dose tail vein injection rats in the control group tail vein injection of normal saline, spinal cord injury by MRI dynamic observation of TAT-PEG-magnetic nano liposome local aggregation and spread through Prussian blue, electron microscopy flame atomic absorption spectrophotometry to determine the further analysis of the local aggregation in spinal cord injury. 1. 7d rats after intravenous injection general good, the rats of various organs Prussian Blue, HE staining showed no significant difference with the control group, a small amount of Prussian blue is only found in high concentration in rat liver tissue sections staining positive particles. TAT-PEG-magnetic nano-liposomes can cross the blood-spinal cord barrier gathered in the local with spinal cord injury, MRI dynamic observations indicate that the drug carrier gradually damage the local concentration, mainly characterized by low T2WI signal. Prussian blue staining was observed gathered in damage local tissue blue dye Fe304 particles, electron microscopy further observed that the aggregation of iron particles in the spinal cord nerve cells, flame atomic absorption spectrophotometry analysis showed that TAT-PEG-magnetic nano liposome spinal cord injury local iron content is relatively increased, the difference was statistically significant (p lt; 0.05) The magnetic nano liposome toxicity, especially at a concentration of less than 7.5 mg (24 h at doses less than 100mg/kg) not have significant effect on rats by tail vein injection of the ways is a safe and effective method . TAT-PEG-magnetic nano-liposomes as a novel drug carrier injection by the intravenous route in vivo, can cross the blood-spinal cord barrier gathered local spinal cord injury, and able to the wrapped substances released into damage the partial nerve cells within expansion of new ideas for the future treatment of spinal cord injury.