Perioperative Bleeding in Patients With Acute Coronary Syndrome Treated With Fondaparinux Versus Low-Molecular-Weight Heparin Before Coronary Artery Bypass Grafting

Intermediate molecular weight-fucosylated chondroitin sulfate from sea cucumber Cucumaria frondosa is a promising anticoagulant targeting intrinsic factor IXa

Thromboembolic diseases pose a serious risk to human health worldwide. Fucosylated chondroitin sulfate (FCS) is reported to have good anticoagulant activity with a low bleeding risk. Molecular weight plays a significant role in the anticoagulant activity of FCS, and FCS smaller than octasaccharide in size has no anticoagulant activity. Therefore, identifying the best candidate for developing novel anticoagulant FCS drugs is crucial. Herein, native FCS was isolated from sea cucumber Cucumaria frondosa (FCScf) and depolymerized into a series of lower molecular weights (FCScfs). A comprehensive assessment of the in vitro anticoagulant activity and in vivo bleeding risk of FCScfs with different molecule weights demonstrated that 10 kDa FCScf (FCScf-10 K) had a greater intrinsic anticoagulant activity than low molecular weight heparin (LMWH) without any bleeding risk. Using molecular modeling combined with experimental validation, we revealed that FCScf-10 K can specifically inhibit the formation of the Xase complex by binding the negatively charged sulfate group of FCScf-10 K to the positively charged side chain of arginine residues on the specific surface of factor IXa. Thus, these data demonstrate that the intermediate molecular weight FCScf-10 K is a promising candidate for the development of novel anticoagulant drugs.

Strategies for sustained release of heparin: A review

Heparin, a sulfate-containing linear polysaccharide, has proven preclinical and clinical efficacy for a variety of disorders. Heparin, including unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), and ultra-low-molecular-weight heparin (ULMWH), is administered systematically, in the form of a solution in the clinic. However, it is eliminated quickly, due to its short half-life, especially in the case of UFH and LMWH. Frequent administration is required to ensure its therapeutic efficacy, leading to poor patient compliance. Moreover, heparin is used to coat blood-contacting medical devices to avoid thrombosis through physical interaction. However, the short-term durability of heparin on the surface of the stent limits its further application. Various advanced sustained-release strategies have been used to prolong its half-life in vivo as preparation technologies have improved. Herein, we briefly introduce the pharmacological activity and mechanisms of action of heparin. In addition, the strategies for sustained release of heparin are comprehensively summarized.

Fondaparinux-associated Thrombocytopenia

Heparin-induced thrombocytopenia (HIT) is an immune-mediated condition causing thrombocytopenia and paradoxical thrombosis after exposure to heparin or low-molecular-weight heparin. It has been rarely reported by Fondaparinux, an artificial pentasaccharide similar to heparin. This manuscript presents a case of HIT associated with fondaparinux use.