Effects of Quercetin-3-O-β-D-Glucuronide on Platelet Apoptosis and Activation in Mice with Immune-Mediated Bone Marrow Failure via PI3K/AKT Pathway

Abstract

To investigate the effect of quercetin-3-O-β-D-glucuronide(QG) on platelet apoptosis and activation in mice with immune-mediated bone marrow failure via PI3K/AKT pathway. An immune-mediated bone marrow failure mice model was established and forty C57BL/6 mice were randomly assigned into 4 groups: normal group, model group,cyclosporine (CsA) group and QG group, with 10 mice in each group.The mice in CsA group were intragastrically administered with 0.027 g/kg CsA daily and the mice in QG group were intragastrically administered with 0.2 g/kg QG daily, while the mice in the normal group and model group were intragastrically administered with normal saline, respectively. After three days of modeling, the mice were euthanized, and the blood was collected through the tail vein. Part of the blood was used for blood routine examination, and the other part was used to prepare washed platelets. Some of the prepared washed platelets were used to detect the expressions of BAX, BAD, caspase-9, phosphatidylserine (PS), platelet activated complex-1 (PAC-1) and P-selectin by flow cytometry; some of washed platelets was used to determine the protein contents of PI3K, p-PI3k, AKT and p-AKT by Western blot; the other part of the washed platelets was used to measure the expressions of PI3K mRNA and AKT mRNA by real-time quantitative PCR (RT-qPCR). In the model group, the absolute platelet count of the mice was significantly decreased, and the levels of BAX, BAD, caspase-9, PS, PAC-1, and P-selectin in the washed platelets were significantly increased, compared to the normal group (P<0.05). At the same time, the expression levels of PI3K, p-PI3K, AKT, p-AKT proteins and PI3K mRNA, AKT mRNA in model group were significantly reduced, compared to the normal group (P<0.05). In the CsA group and QG group, the expression levels of BAX, BAD, caspase-9, PS, PAC-1, and P-selectin in the washed platelets were significantly reduced (P<0.05), while the levels of PI3K, p-PI3K, AKT, p-AKT and PI3K mRNA, AKT mRNA were significantly increased, compared to the model group (P<0.05). QG can reduce platelet apoptosis in mice with immune-mediated bone marrow failure, and activation of some platelets is involved, which may be related to the regulation of PI3K/AKT pathway.