LXRß is involved in the control of platelet production from megakaryocytes.

Liver X receptor ß (LXRß), a nuclear receptor involved in important cellular processes such as cholesterol, glucose and fatty acid metabolism, was suggested to be involved in platelet aggregation but its detailed roles are not clear. In the present study, we evaluated the contribution of LXRß to platelet functions and production. In the systemic collagen-epinephrine thrombosis mouse model, LXRß-deficient mice showed increased area of blood clots compared with control wide-type littermates. The aggregation of LXRß-deficient platelets in response to ADP was stronger than that of control mice platelets. More importantly, the number of platelets in blood of LXRß-deficient mice was significantly higher than that of wild-type mice, especially for female mice. Knockdown of LXRß expression in human megakaryoblastic Dami cells also enhanced cell polyploidization, formation of proplatelets and production of platelet-like particles. Increase in expression levels of proteins related to oxidative phosphorylation such as NADH:ubiquinone oxidoreductase core subunit V1 (Ndufv1) was observed in LXRß-knockdown Dami cells. The levels of Ndufv1 in LXRß-deficient mice platelets were also higher than that of wild-type mice. Taken together, our findings suggested LXRß might participate in control of platelet production from megakaryocytes by regulating mitochondrial metabolism.

Application of Feedback System Control Optimization Technique in Combined Use of Dual Antiplatelet Therapy and Herbal Medicines.

Aim: Combined use of herbal medicines in patients underwent dual antiplatelet therapy (DAPT) might cause bleeding or thrombosis because herbal medicines with anti-platelet activities may exhibit interactions with DAPT. In this study, we tried to use a feedback system control (FSC) optimization technique to optimize dose strategy and clarify possible interactions in combined use of DAPT and herbal medicines. Methods: Herbal medicines with reported anti-platelet activities were selected by searching related references in Pubmed. Experimental anti-platelet activities of representative compounds originated from these herbal medicines were investigated using in vitro assay, namely ADP-induced aggregation of rat platelet-rich-plasma. FSC scheme hybridized artificial intelligence calculation and bench experiments to iteratively optimize 4-drug combination and 2-drug combination from these drug candidates. Results: Totally 68 herbal medicines were reported to have anti-platelet activities. In the present study, 7 representative compounds from these herbal medicines were selected to study combinatorial drug optimization together with DAPT, i.e., aspirin and ticagrelor. FSC technique first down-selected 9 drug candidates to the most significant 5 drugs. Then, FSC further secured 4 drugs in the optimal combination, including aspirin, ticagrelor, ferulic acid from DangGui, and forskolin from MaoHouQiaoRuiHua. Finally, FSC quantitatively estimated the possible interactions between aspirin:ticagrelor, aspirin:ferulic acid, ticagrelor:forskolin, and ferulic acid:forskolin. The estimation was further verified by experimentally determined Combination Index (CI) values. Conclusion: Results of the present study suggested that FSC optimization technique could be used in optimization of anti-platelet drug combinations and might be helpful in designing personal anti-platelet therapy strategy. Furthermore, FSC analysis could also identify interactions between different drugs which might provide useful information for research of signal cascades in platelet.