ABSTRACT
Objective: To explore the function and mechanism of microRNA-155 to regulate the angiogenesis after the cerebral infarction of rats through the angiotensin II receptor 1 (AT1R)/vascular endothelial growth factor (VEGF) signaling pathway. Methods: Female SD rats were chosen for the construction of cerebral infarction model of rats using the modified right middle cerebral artery occlusion. The real-time PCR (RT-PCR) method was employed to detect the expression of microRNA-155 in each group at different time points after the cerebral infarction (1 h, l d, 3 d and 7 d). SD rats were randomly divided into four groups (n = 20 rats): sham operation group (Sham group), MACO group, MACO+microRNA-155 mimic group, and MACO+microRNA-155 inhibitor group. Sham group was given the free graft, while MACO+microRNA-155 mimic group and MACO+microRNA-155 inhibitor group were treated with microRNA-155 mimic and microRNA-155 inhibitor respectively. The Zea Longa 5-point scale was used to score the neurologic impairment of rats in each group; 2, 3, 5-triphenyl tetrazolium chloride staining to evaluate the volume of cerebral infarction of rats in each group; the immunohistochemistry to detect the expression of CD31; Western blot and RT-PCR to detect the expression of AT1R and VEGF receptor 2 (VEGFR2). Results: The expression of microRNA-155 was increased in the cerebral ischemia tissue after the cerebral infarction. It was significantly increased at 1 d of ischemia and maintained at the high level for a long time. Rats in the Sham group had no symptom of neurologic impairment, while rats in the MACO group had the obvious neurologic impairment. After being treated with microRNA-155 inhibitor, the neural function of MACO rats had been improved, with the decreased area of cerebral infarction. But after being treated with microRNA-155 mimic, the neural function was further worsened, with the increased area of cerebral infarction. Results of immunohistochemical assay indicated that microRNA-155 inhibitor could up-regulate the expression of CD31, while microRNA-155 mimic could down-regulate the expression of CD31. The RT-PCR found that, after being treated with microRNA-155 inhibitor, MACO rats had the increased expression of AT1R and VEGFR2 messenger RNA (mRNA); but after being treated with microRNA-155 mimic, the expression of AT1R and VEGFR2 mRNA was decreased. Results of Western blot showed that, after being treated with microRNA-155 inhibitor, MACO rats had the increased expression of AT1R and VEGFR2 mRNA; but after being treated with microRNA-155 mimic, the expression of AT1R and VEGFR2 mRNA was decreased. Conclusions: The inhibition of microRNA-155 can improve the neurologic impairment of rats with the cerebral infarction, reduce the volume of cerebral infarction and effectively promote the angiogenesis in the region of ischemia, which may be mediated through AT1R/VEGFR2 pathway.
ABSTRACT
OBJECTIVE@#To explore the function and mechanism of microRNA-155 to regulate the angiogenesis after the cerebral infarction of rats through the angiotensin II receptor 1 (AT1R)/vascular endothelial growth factor (VEGF) signaling pathway.@*METHODS@#Female SD rats were chosen for the construction of cerebral infarction model of rats using the modified right middle cerebral artery occlusion. The real-time PCR (RT-PCR) method was employed to detect the expression of microRNA-155 in each group at different time points after the cerebral infarction (1 h, l d, 3 d and 7 d). SD rats were randomly divided into four groups (n = 20 rats): sham operation group (Sham group), MACO group, MACO+microRNA-155 mimic group, and MACO+microRNA-155 inhibitor group. Sham group was given the free graft, while MACO+microRNA-155 mimic group and MACO+microRNA-155 inhibitor group were treated with microRNA-155 mimic and microRNA-155 inhibitor respectively. The Zea Longa 5-point scale was used to score the neurologic impairment of rats in each group; 2, 3, 5-triphenyl tetrazolium chloride staining to evaluate the volume of cerebral infarction of rats in each group; the immunohistochemistry to detect the expression of CD31; Western blot and RT-PCR to detect the expression of AT1R and VEGF receptor 2 (VEGFR2).@*RESULTS@#The expression of microRNA-155 was increased in the cerebral ischemia tissue after the cerebral infarction. It was significantly increased at 1 d of ischemia and maintained at the high level for a long time. Rats in the Sham group had no symptom of neurologic impairment, while rats in the MACO group had the obvious neurologic impairment. After being treated with microRNA-155 inhibitor, the neural function of MACO rats had been improved, with the decreased area of cerebral infarction. But after being treated with microRNA-155 mimic, the neural function was further worsened, with the increased area of cerebral infarction. Results of immunohistochemical assay indicated that microRNA-155 inhibitor could up-regulate the expression of CD31, while microRNA-155 mimic could down-regulate the expression of CD31. The RT-PCR found that, after being treated with microRNA-155 inhibitor, MACO rats had the increased expression of AT1R and VEGFR2 messenger RNA (mRNA); but after being treated with microRNA-155 mimic, the expression of AT1R and VEGFR2 mRNA was decreased. Results of Western blot showed that, after being treated with microRNA-155 inhibitor, MACO rats had the increased expression of AT1R and VEGFR2 mRNA; but after being treated with microRNA-155 mimic, the expression of AT1R and VEGFR2 mRNA was decreased.@*CONCLUSIONS@#The inhibition of microRNA-155 can improve the neurologic impairment of rats with the cerebral infarction, reduce the volume of cerebral infarction and effectively promote the angiogenesis in the region of ischemia, which may be mediated through AT1R/VEGFR2 pathway.
ABSTRACT
The papers regarding moxibustion published in science citation index (SCI) journals for the recent 5 years were searched to explore the international tendency of moxibustion researches, which provided references for moxibustion to have a better internationalization. With methods of internet search and database search, a total of 116 papers regarding moxibustion were included. These papers were published in 40 kinds of journals, mostly in Britain and the United States. The journal with the highest impact factor was Stroke, which had 5729 points. The number and impact factor of these journals were inferior to those of acupuncture journal. Compared among these journals, the depth and width of moxibustion research were increasing year by year. The category of diseases related with moxibustion is mainly digestive system diseases, motor system diseases and urinary-genital system diseases. The type of papers was characterized with clinical observation and mechanism research. Researches related with moxibustion included moxibustion dose and safety. It was believed that the international recognition of moxibustion effectiveness, standardization of moxibustion manipulation, standardization research, etc. were needed to be solved in the further.