Effect of calcitriol supplementation on the activity of matrix metalloproteinase 9 in an experimental model of ischemic stroke

Abstract

Background After a stroke, both local and systemic inflammatory responses are activated in the body. The degree of response depends on the activity of several inflammatory factors, including the matrix metalloproteinase 9 enzyme. This enzyme is dependent on zinc and causes the blood-brain barrier to break and destroy it, which in turn causes more immune cells, including lymphocytes, to invade the ischemic area. Considering the role of steroid hormone calcitriol in controlling inflammation, in the present study, the effect of calcitriol on the level of MMP9 activity after induction of ischemic stroke in MCAO experimental model is investigated. Material and method 3 groups of 5 rats were selected, the groups are ischemia control group, calcitriol drug group and control group (sham) respectively. Stroke was induced by middle cerebral artery occlusion (MCAO) and calcitriol was injected intraperitoneally for 3 days. After performing the behavioral tests, the volume of the ischemic area in the brain was measured. The expression of MMP9 enzyme activity in blood serum was investigated by zymography technique. Zymography is a technique based on SDS PAGE that examines the activity of specific enzymes. Results According to the observations of the behavioral test, animals in the drug group had better conditions and the volume of cerebral infarction decreased in this group. Compared to the other groups, the mmp-9 band was less thick in the drug group, which indicated a decrease in the activity of this enzyme in the drug group. In the acute phase of stroke, this enzyme increases, and cholesterol reduces the activity of this enzyme and prevents its increase. Conclusion The results show that cholesterol participates in inflammatory mechanisms by inhibiting mmp-9 and prevents bleeding and secondary destruction, and as a result, improves stroke symptoms.