摘要： Objective To explore the possible mechanism of eucommia ulmoides leaves total flavonoids promoting neurological repair in rats with cerebral hemorrhage from the Ras homolog gene family member A (RhoA)/Rho-associated coiled-coil protein kinase (ROCK) pathway. Methods SD male rats were used to establish cerebral hemorrhage model by the modified double injection method, and they were randomly divided into the sham operation group, the model group, the eucommia ulmoides leaves total flavonoids group, the RhoA inhibitor group, the RhoA agonist group, and the eucommia ulmoides leaves total flavonoids + RhoA agonist group, with 20 rats in each group. The eucommia ulmoides leaves total flavonoids group was intragaically treated with 200 mg/kg eucommia ulmoides leaves total flavonoids. The RhoA inhibitor group was intraperitoneally injected with 1 mg/kg RhoA inhibitor Y27632. The RhoA agonist group was intraperitoneally injected with 30 μg/kg RhoA agonist U-46619, and the eucommia ulmoides leaves total flavonoids + RhoA agonist group was intraperitoneally injected with 200 mg/kg eucommia ulmoides leaves total flavonoids and 30 μg/kg RhoA agonist U-46619. The model group and sham operation group were given 10 mL/kg normal saline once a day for 7 consecutive days. After the administration, the behavioral changes of rats were observed with the naked eye and the neurological deficit symptoms were assessed by the modified neurological severity score (mNSS). Brain tissue was taken and weighed, and the water content of the brain tissue was calculated according to the formula to evaluate the cerebral edema, then the brain tissue slices were prepared and the volume percentage of the cerebral hematoma was calculated according to the formula. Changes in the structure of nerve synapses in perihematoma tissue were observed by transmission electron microscope. Changes of neuronal apoptosis of perihematoma tissue were observed by TUNEL staining method. Changes in neuron skeleton of perihematoma tissue were detected by phalloidin staining. The expression levels of RhoA, ROCK, cytoskeleton protein (F-actin), filament protein (cofilin), phosphorylated cofilin (p-cofilin), neuron and synapse growth promoting proteins [nerve growth factor (NGF), neurotrophic factor 3 (NT3), postsynaptic dense protein-95 (PSD-95), synaptophysin (SYP)] in perihematoma tissue were detected by Western blot assay. Results Compared with the sham operation group, the neurological deficit scores, water content of brain tissue and the percentage of cerebral hematoma volume were increased in the model group, the neuronal apoptosis, skeleton structure damage, and changes in the structure of nerve synapses in the surrounding tissue of the hematoma were severer, the activation of RhoA/ROCK pathway increased, and the expression of neuron and synapse growth promoting proteins decreased (P<0.05). Eucommia ulmoides leaves total flavonoids or RhoA inhibitor intervention treatment could inhibit changes in neuron skeleton structure mediated by RhoA/ROCK pathway activation, increase the expression of neuron and synapse growth promoting proteins, alleviate neuronal damage and apoptosis in surrounding tissues of the hematoma after cerebral hemorrhage, and promote nerve function repair (P<0.05). RhoA agonist could promote the activation of RhoA/ROCK pathway, aggravate the neurological damage after cerebral hemorrhage, and weaken the nerve function repairing effect of eucommia ulmoides leaves total flavonoids (P<0.05). Conclusion Eucommia ulmoides leaves total flavonoids can improve the symptoms of cerebral hemorrhage in rats and promote the nerve function repair by inhibiting the activation of RhoA/ROCK pathway.

中图分类号: 

• R285.5