Differential Proteomic Analysis of Platelets Suggested Possible Signal Cascades Network in Platelets Treated with Salvianolic Acid B

Salvianolic acid B (SB) is an active component isolated from Danshen, a traditional Chinese medicine widely used for the treatment of cardiovascular disorders. Previous study suggested that SB might inhibit adhesion as well as aggregation of platelets by a mechanism involving the integrin α2β1. But, the signal cascades in platelets after SB binding are still not clear.In the present study, a differential proteomic analysis (two-dimensional electrophoresis) was conducted to check the protein expression profiles of rat platelets with or without treatment of SB. Proteins altered in level after SB exposure were identified by MALDI-TOF MS/MS. Treatment of SB caused regulation of 20 proteins such as heat shock-related 70 kDa protein 2 (hsp70), LIM domain protein CLP-36, copine I, peroxiredoxin-2, coronin-1 B and cytoplasmic dynein intermediate chain 2C. The regulation of SB on protein levels was confirmed by Western blotting. The signal cascades network induced by SB after its binding with integrin α2β1 was predicted. To certify the predicted network, binding affinity of SB to integrin α2β1 was checked in vitro and ex vivo in platelets. Furthermore, the effects of SB on protein levels of hsp70, coronin-1B and intracellular levels of Ca²+ and reactive oxygen species (ROS) were checked with or without pre-treatment of platelets using antibody against integrin α2β1. Electron microscopy study confirmed that SB affected cytoskeleton structure of platelets.Integrin α2β1 might be one of the direct target proteins of SB in platelets. The signal cascades network of SB after binding with integrin α2β1 might include regulation of intracellular Ca²+ level, cytoskeleton-related proteins such as coronin-1B and cytoskeleton structure of platelets

Biomechanics and modeling of tissue-engineered heart valves

Heart valve tissue engineering (HVTE) is a promising technique to overcome the limitations of currently available heart valve prostheses. However, before clinical use, still several challenges need to be overcome. The functionality of the developed replacements is determined by their biomechanical properties and, ultimately, by their collagen architecture. Unfortunately, current techniques are often not able to induce a physiological tissue remodeling, which compromises the long-term functionality. Therefore, a deeper understanding of the process of tissue remodeling is required to optimize the phenomena involved via improving the current HVTE approaches. Computational simulations can help in this process, being a valuable and versatile tool to predict and understand experimental results. This chapter first describes the similarities and differences in functionality and biomechanical properties between native and tissue-engineered heart valves. Secondly, the current status of computational models for collagen remodeling is addressed and, finally, future directions and implications for HVTE are suggested