Calcium-Sensing Receptor in Human Peripheral Blood T Lymphocytes Is Involved in the AMI Onset and Progression through the NF-κB Signaling Pathway

Abstract

Acute myocardial infarction (AMI) is a condition triggered by an inflammatory process that seriously affects human health. Calcium-sensing receptor (CaSR) in T lymphocytes is involved during the inflammation reaction. However, the relationship between them is not very clear. In this study, we collected human peripheral blood T lymphocytes from patients with AMI and in different stages of percutaneous coronary intervention (PCI) (at the onset of AMI, the first day after PCI (PCI-1), PCI-3, and PCI-5) to study the CaSR and NF-κB pathway protein expression, cytokine release and T cell apoptosis. The results showed that the expressions of CaSR, P-p65, Caspase-12, and the secretions of Th-1 and Th-2 type cytokines were increased at the onset of AMI, especially on the PCI-1. Meanwhile, the apoptosis rate of CD3+, CD4+ and CD8+ T lymphocytes also increased. However, from PCI-3, all the indicators began to decline. In addition, we also found that positive CaSR small interfering RNA (siRNA) transfection in T lymphocytes and NF-κB pathway blocker Bay-11-7082 reversed the increased expressions of CaSR, P-p65, Caspase-12, reduced the secretions of Th-1 and Th-2 type cytokines, and decreased T lymphocytes apoptosis rate not only in the AMI patients but also in the normal controls. All of these results indicated that CaSR in the human peripheral blood T lymphocytes were involved in the AMI onset and progression, which probably was related to the NF-κB pathway. Our study demonstrated the relationship between AMI and CaSR, and will provide new effective prevention theory and new targets for drug treatment.

Calcium‑sensing receptors in human peripheral T�lymphocytes and AMI: Cause and effect

“…It was also found that, no matter how U0126 or SP600125 changed, the degree of cytokine release was lower, compared with that induced by the positive CaSR siRNA plasmid. These results were consistent with our previous results (13). Therefore, the activation of CaSR had a specific effect, not only through the NF-κB pathway, but also through partial MAPK pathways.…”

“…The previous study also revealed that the activation of CaSR was involved in cardiac ischemia-reperfusion (I/R) injury and that it may promote ventricular cardiomyocyte apoptosis in neonatal rats through activating the MAPK signaling pathway (12). In another of our previous studies, it was confirmed that the activation of CaSR in T lymphocytes regulated cell physiological function through NF-κB signaling pathways in AMI and percutaneous coronary intervention (PCI) postoperative processes (13). In the experiment, it was found that CaSR small interfering RNA (siRNA)-positive plasmid-transfected T lymphocytes and the NF-κB pathway inhibitor Bay-11-7082 decreased the level of phosphorylated (P-) p65 in AMI.…”

“…In our previous study, it was found that CaSR can activate a variety of cell signal transduction pathways; the results of the previous study (13) showed that the degree of change of levels of cytokines induced by the NF-κB pathway blocker Bay-11-7082 was lower than that induced by the positive CaSR siRNA plasmid. This raised the question of whether there is another pathway involved in the pathological process of AMI.…”

“…As in the previous experiment (13), the present study prospectively enrolled 60 patients (47 men and 13 women) with AMI. Informed consent was provided from these patients and controls.…”

“…siRNA transfection. As described in the previous study (13), T lymphocytes at a cell density of 8x10 6 were resuspended in 100 µl nucleofector solution, following which they were transfected with 5 µg negative or positive plasmid labeled with FITc using a Lonza Nucleofector II single nucleus transfection apparatus (Lonza Group, Ltd.). Following transfection, the cells recovered for 6 h. Protein lysate was harvested 24 h post-transfection.…”