ABSTRACT
Objective To study the effects of morroniside on the expression of Wnt signaling-related transcription factors neurogenin 2 (Ngn2), Pax6 and Tbr2 in the ischemic ipsilateral cortex 7 days after cerebral ischemia-reperfusion in rats. Methods 15 male Sprague-Dawley rats were randomly divided into sham group (n=3), ischemia group (n=3), and morroniside groups (low, medium and high dosage groups, n=3). The middle cerebral artery were occluded for 30 min, and re-perfused. Morroniside was administered intragastrically once a day at dose of 30 mg/kg, 90 mg/kg and 270 mg/kg 3 hours after operation. The expression of Ngn2, Pax6 and Tbr2 in the ischemic ipsilateral cortex were detected with Western blotting analysis 7 days after operation. Results The expression of Ngn2 increased in the ischemia group compared with the sham group (P<0.05), and it further increased the morroniside groups of medium and high dosage compared with the ischemia group (P<0.01). There was no significant difference between the ischemia group and sham group in the expression of Pax6, while it increased the morroniside groups of medium and high dosage compared with the ischemia group (P<0.01). There was no significant difference among all the groups in the expression of Tbr2. Conclusion Morroniside could increase the expression of Ngn2 and Pax6 in the ischemic ipsilateral cortex 7 days after ischemia-reperfusion in rats, suggesting promoting the neurogenesis after ischemia.
ABSTRACT
@#Objective To study the effects of morroniside on the expression of Wnt signaling-related transcription factors neurogenin 2 (Ngn2), Pax6 and Tbr2 in the ischemic ipsilateral cortex 7 days after cerebral ischemia-reperfusion in rats. Methods 15 male Sprague-Dawley rats were randomly divided into sham group (n=3), ischemia group (n=3), and morroniside groups (low, medium and high dosage groups, n=3). The middle cerebral artery were occluded for 30 min, and re-perfused. Morroniside was administered intragastrically once a day at dose of 30 mg/kg, 90 mg/kg and 270 mg/kg 3 hours after operation. The expression of Ngn2, Pax6 and Tbr2 in the ischemic ipsilateral cortex were detected with Western blotting analysis 7 days after operation. Results The expression of Ngn2 increased in the ischemia group compared with the sham group (P<0.05), and it further increased the morroniside groups of medium and high dosage compared with the ischemia group (P<0.01). There was no significant difference between the ischemia group and sham group in the expression of Pax6, while it increased the morroniside groups of medium and high dosage compared with the ischemia group (P<0.01). There was no significant difference among all the groups in the expression of Tbr2. Conclusion Morroniside could increase the expression of Ngn2 and Pax6 in the ischemic ipsilateral cortex 7 days after ischemia-reperfusion in rats, suggesting promoting the neurogenesis after ischemia.
ABSTRACT
Unipolar brush cells (UBCs) are excitatory interneurons with their somata located in the granular layer. Recently, T-brain factor 2 (Tbr2) was shown to be expressed in a subset of UBCs in mouse cerebellum. Scrambler mice exhibit severe cerebellum abnormalities, including the failure of embryonic Purkinje cell dispersal and a complete absence of foliation due to a mutation in the disabled-1 adaptor protein. Since most UBC markers are expressed postnatally, it has proven difficult to identify the relationship between developing Purkinje cell clusters and migrating UBCs. Because scrambler mice closely mimic normal embryonic day 18 cerebellum, we examined whether Tbr2-positive UBCs are associated with Purkinje cell cluster markers such as zebrin II, which is the most studied compartmentation marker in the cerebellum. We investigated the distribution of Tbr2-positive UBCs in this mutant by using anti-Tbr2 immunocytochemistry. The data revealed that Tbr2 immunoreactivity was exclusively present in the nucleus of UBCs in scrambler cerebellum. Based on expression data, a Tbr2-positive UBC map was constructed. In addition, Tbr2-positive UBCs are found associated with ectopic zebrin II-immunoreactive Purkinje cell clusters in scrambler cerebellum. These data suggest that UBCs use Purkinje cell compartmentation to migrate into their final position through interactions with the embryonic array of specific Purkinje cell subtypes.