Study on the mechanism of Tanhuo Prescription in the regulation of M1-type microglia activation and reducing the damage of brain tissue in rats with cerebral ischemia / 国际中医中药杂志

ABSTRACT

Objective:To observe the effect and mechanism of Tanhuo Prescription on regulating the activation of M1 microglia and alleviating brain tissue injury in rats with cerebral ischemia.Methods:Male SD rats were divided into sham-operation group, model group, Tanhuo Prescription high-(3.68 g/kg), medium-(1.84 g/kg), low-dosage(0.92 g/kg) groups, and ginaton group (0.06 g/kg) using random number table method. Except for the sham-operation group, the other groups established cerebral ischemia rat models using the middle cerebral artery occlusion method. The balance beam walking test was used to evaluate the symptoms of neurological deficit. MRI-T2 mapping was used to measure the damage to brain tissue. LFB staining was used to observe the damage to nerve fibers. HE staining was used to observe the damage to nerve cell, and Iba-1 and CD16/Iba-1 immunofluorescence staining were used to observe the condition of microglial activation.Results:Compared with the model group, the scores of balance beam walking ability of rats in Tanhuo Prescription high-dose group and ginaton group at 24 h, 48 h and 72 h after ischemia were significantly improved ( P<0.05, P<0.01). The scores of balance beam walking ability of rats in Tanhuo Prescription low- and medium- dose groups at 72 h after ischemia were improved ( P<0.01). Compared with the model group, the T2 values of the cortex and striatum around the infarct of rats in Tanhuo Prescription high-dose group and ginaton group were significantly reduced ( P<0.05, P<0.01), and the T2 values of the striatum around the infarct of rats in Tanhuo Prescription low- and medium- dose groups were significantly reduced ( P<0.05). Compared with the model group, the LFB IOD of the cortex, striatum and outer capsule around the infarct decreased in the Tanhuo Prescription high-,low-dose group and ginaton group ( P<0.01). The LFB IOD of striatum around infarct decreased in medium- dose Tanhuo Prescription group ( P<0.01). Compared with the model group, the pathological injury degree of the striatum around the infarct of rats in Tanhuo Prescription low- ,medium-, and high-dose groups decreased, and the cell density decreased ( P<0.05, P<0.01). The density of the cortical and striatum cells around the infarct of rats in ginaton group increased ( P<0.01, P<0.05). Compared with the model group, the number of Iba-1 and CD16/Iba-1 positive cells in the cortex and striatum around the infarct decreased in Tanhuo Prescription medium-, high-dose and ginaton groups ( P<0.01). The number of CD16/Iba-1 positive cells in the cortex and striatum around the infarct of rats in Tanhuo Prescription low-dose group decreased ( P<0.01), and the number of Iba-1 positive cells in the striatum around the infarct of rats in Tanhuo Prescription low-dose group decreased ( P<0.01). Conclusion:Tanhuo Prescription can improve the symptoms of neurological deficits in rats with cerebral ischemia, reduce the neuropathological damage in the cerebral area around ischemic infarction, and inhibit the activation of M1 microglia.