Objective: To observe the effect of penetrative needling from "Baihui" (GV20) to "Qubin" (GB7) on neural stem cell proliferation and sonic hedgehog (Shh) signaling in subventricular zone (SVZ) in intracerebral hemorrhage (ICH) rats so as to explore its mechanisms underlying improvement of ischemic injury of brain.
Methods: Male SD rats were randomly divided into blank control, model, acupuncture and agonist (Purmorphamine, an activator of Shh signaling pathway) groups (n＝18 in each group, 6 for H．E. stain, 6 for examining neuronal cell proliferation, and 6 for immunohistochemistry). The ICH model was established by injecting autogenous blood (50 µL) into the right caudate nucleus. The neurological defect was scored with refe-rence to Bederson's method. Penetrative needling from GV20 to GB7 was performed by manipulating the needle for 6 min (repeated 3 times in 30 min), once daily for 7 days. Intraperitoneal injection of Purmorphamine (1 mg/mL, 1 mg/kg) was performed, once daily for 7 days. Histopathological changes of the hemorrhagic penumbra region were observed under microscope after H．E. stain, the newborn neural stem cell proliferation (BrdU＋/Nestin＋ double labeled cells) in the SVZ was observed by immunofluorescence after intraperitoneal injection of BrdU (50 mg/kg), and the expression of Shh and glioma-associated hemolog-1 (Gli1) detected by immunohistochemistry.
Results: After modeling, the neurological score and expression levels of Shh and Gil1 proteins were significantly increased in the model group relevant to the blank control group (P<0.001). Following the interventions, the neurological score was evidently decreased (P<0.05), while the number of BrdU＋/Nestin＋ double labeled cells and the expression levels of Shh and Gil1 proteins were significantly increased in both acupuncture and agonist groups in comparison with the model group (P<0.001). No significant differences were found between the acupuncture and agonist groups in down-regulating the neurological score and in up-regulating the number of BrdU＋/Nestin＋ double labeled cells and the expression of Shh and Gil1 proteins (P>0.05). Outcomes of H．E. stain showed obvious edema, disordered arrangement of cells, infiltration of inflammatory cells and red blood cells with glial cell hyperplasia around the hematoma area in the model group, which was relatively milder in both acupuncture and agonist groups such as in basic disappearance of edema and inflammatory reaction.
Conclusion: Penetrative needling from GV20 to GB7 can obviously improve neurological function in ICH rats, which is related to its effects in activating Shh/Gil1 signaling and in further promoting neural stem cell proliferation in the SVZ region.
Keywords: Acupuncture; Intracerebral hemorrhage; Neural stem cell proliferation; Shh/Gil1 signaling; Subventricular zone.