The study of the Mongolian traditional medicine Khurtsiin deed-6 analgesic and anti-inflammatory effect by inhibiting glial cell activation in nitroglycerin-induced migraine in rats

Background: Migraine is a highly prevalent neurovascular disorder with complicated treatment due to multifactorial pathophysiology. During the recent years, the prevalence of migraine in Mongolia is increasing and has reached 26.5% by 2019 which indicates an increase of 5.2% over the past 10 years. The industry of traditional medicine in Mongolia has a long history of development, hence, it is evident that various herbal medicines such as but not limited to Khurtsiin deed-6 (KhD-6) can be considered as generally safe and effective against several diseases including migraine. KhD-6’s single component has shown excellent analgesic, anti-inflammatory and neuroprotective effect, while the whole compound effectiveness and molecular mechanism had not been assessed for the treatment of migraine. Objectives: To study the effects of Khurtsiin deed-6 compound on inflammation and neuronal cell damage in migraine model in rats. Methods: A total of 36 rats were randomly divided into the following six groups including control group, Nitroglycerin-induced (NTG-induced) migraine model group, KhD-6 groups of 50 mg/kg, 100 mg/kg and 150 mg/kg doses, and Ibuprofen (IBU) 85 mg/kg treated group. Corresponding treatments were administered intragastrically for 10 days to animals of experimental groups. Then NTG-induced migraine model group, three KhD-6 groups and IBU group were subcutaneously injected with Nitroglycerin (10mg/kg) 1 h after the last treatment. Experimental animals were observed for two hours after Nitroglycerin injection to confirm the model establishment. After four hours, all rats were anesthetized and blood was collected from three rats from each group in order to detect levels of Nitric oxide (NO), calcitonin gene-related peptide (CGRP) and endothelin (ET) by ELISA method. The remaining three animals of each experimental group were perfused under anesthesia for the removal of their brains and isolation of the trigeminal nucleus caudalis (TNC). A polymerase chain reaction (PCR) method was used to analyze OX42, COX2, RAGE, GFAP, BDNF, BAX, and Bcl expressions. Results: NTG-induced rat migraine model presents increased NO and CGRP levels in serum as well as c-Fos expression in the brain trigeminal nucleus area, which indicates that the migraine model was successfully generated. NO and CGRP levels in serum were suppressed in KhD-6 and IBU treated groups. The c-Fos expression decreased significantly in the TNC not only in Khurtsiin-6 compound, but also in IBU treated groups. Furthermore, KhD-6 compound inhibits neuro-inflammatory pathways by reducing COX2 expression, OX42 and GFAP activation. It inhibits neuronal cell death through suppressing RAGE, BAX, Bcl expression and increasing BDNF expression. Conclusion: KhD-6 offers analgesic and neuroprotective effects in the NTG-induced migraine rat model by inhibiting the activation of glial cells and the secretion of neuroinflammatory factors in the TNC region.