Acupuncture intervention prolongates thrombolysis time window by regulating cerebral cortex angiogenesis-related genes and proteins in cerebral infarction rats

Abstract

To observe the effect of acupuncture on the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin (Endostatin, ES) mRNAs and proteins (angiogenesis related factors) in the ischemic penumbra region in rats with cerebral infarction (CI), so as to explore its underlying mechanisms in prolonging the time window of thrombolysis therapy for CI. A total of 48 male SD rats were randomly divided into sham operation, model, medication (6 h thrombolysis) and acupuncture (Acupunct)+medication groups (n=12 in each group). The CI model was established using modified auto-thrombus method. Six hours after thrombolysis, recombinant human tissue plasminogen activator (rt-PA,10 mg/kg) was given to rats of the thrombolysis group through tail vein. Acupuncture was applied at "Shuigou"(CV26) and bilateral "Neiguan" (PC6) 2 h after successful modeling, and the needles were retained for 30 minutes. Cerebral blood flow (CBF) was monitored during modeling in each group, and the neurological deficit score (0-7 points) was given 2 h and 24 h after successful modeling according to Bederson's methods. The cerebral infarction volume was observed after triphenyltetrazole chloride (TTC) staining. The protein and mRNA expression levels of VEGF, bFGF and ES in the ischemic penumbra region of the right cerebral cortex were detected by Western blot and real-time PCR, separately. The neurological deficit score at both 2 h and 24 h after modeling, percentage of cerebral infarction volume, and the expression levels of VEGF, bFGF and ES proteins and mRNAs in the model group were significantly higher than those of the sham operation group (P<0.01, P < 0.05). Compared with the model group, the neurological deficit score 24 h (not at 2 h) after modeling and percentage of cerebral infarction volume, and the expression levels of ES protein and mRNA in the Acupunct+medication group (not in the medication group) were notably lower (P<0.05, P<0.01), while the expression levels of VEGF and bFGF proteins and mRNAs in the Acupunct +medication group (not in the medication group) were considerably higher (P<0.01, P<0.05). No significant differences were found between medication and model groups in the CI percentage, VEGF, bFGF and ES proteins and mRNAs (P>0.05). The therapeutic effect of Acupunct +medication group was significantly superior to that of medication in lowering neurological deficit score, percentage of CI volume and expression of ES protein and mRNA and in up-regulating the expression of VEGF and bFGF proteins and mRNAs (P<0.05, P<0.01). Acupuncture and timely intervention can prolong the time window of thrombolysis in CI rats, which may be related to its function in up-regulating the expression of VEGF and bFGF mRNAs and proteins and in down-regulating the expression of ES mRNA and protein in ischemic cerebral cortex.