Kallikrein inhibitors limit kinin B(2) antagonist-induced progression of oedematous to haemorrhagic pancreatitis in rats

Discovery and development of Factor Xa inhibitors (2015-2022)

As a pathological coagulation process, thrombus can lead to many serious diseases, including ischemic stroke, acute myocardial infarction (AMI), acute coronary syndrome (ACS), and deep venous thrombosis (DVT). And anticoagulant drugs are one of the most effective ways to prevent and treat these diseases. Although macromolecular anticoagulant drugs such as low molecular weight heparins (LMWHs) are widely used in the clinic, their characteristics of requiring injectable use hinder their further promotion in the clinic, and the disadvantages of oral anticoagulant drugs, such as warfarin and dabigatran etexilate, which can easily cause bleeding adverse effects, are also not addressed. Factor Xa (FXa) has gained attention because it lies at the intersection of the coagulation cascade pathways, whereas subsequently introduced Factor Xa inhibitors such as rivaroxaban and apixaban, among others, have gained market popularity because of their high potency for anticoagulation and high specificity for Factor Xa when administered orally. But some of the drawbacks that these Factor Xa inhibitors have simultaneously such as fewer indications and the lack of an effective reversal drug when bleeding occurs are urgently addressed. The development of new Factor Xa inhibitors therefore becomes one means of addressing these questions. This article summarizes the small molecule Factor Xainhibitors developed from 2015 to 2022, classifies them according to their scaffolds, focuses on the analysis of their structure-activity relationships, and provides a brief assessment of them.

Targeting the kallikrein-related peptidases for drug development

Kallikrein-related peptidases (KLKs) constitute a family of 15 serine proteases. Recent studies have shed light on key physiological functions of KLK enzymes and implicate their deregulation in major human pathologies such as neurodegenerative and inflammatory diseases, skin conditions, asthma, and cancer. Consequently, KLKs have emerged as novel targets for pharmacological intervention. Given the pleiotropic roles of KLKs, both activators and inhibitors of KLK activities are of therapeutic interest. For example, inhibitors of hyperactive KLKs in the epidermis would be effective against excess skin desquamation and inflammation, whereas KLK activators could benefit hyperkeratosis caused by diminished KLK proteolysis. Expression of active KLKs by cancer cells and tissues can be exploited to target prodrugs that are proteolytically cleaved to release a cytotoxic compound or a cytolytic toxin at the site of KLK protease activity. Here, we review current approaches for the design and testing of KLK-based therapeutics.

The kallikrein-kinin system in health and in diseases of the kidney

Since kallikrein was discovered as a vasodilatory substance in human urine, the kallikrein-kinin system (KKS) has been considered to play a physiological role in controlling blood pressure. Gene targeting experiments in mice in which the KKS has been inactivated to varying degrees have, however, questioned this role, because basal blood pressures are not altered. Rather, these experiments have shown that the KKS has a different and important role in preventing changes associated with normal senescence in mice, and in reducing the nephropathy and accelerated senescence-associated phenotypes induced in mice by diabetes. Other experiments have shown that the KKS suppresses mitochondrial respiration, partly by nitric oxide and prostaglandins, and that this suppression may be a key to understanding how the KKS influences senescence-related diseases. Here we review the logical progression and experimental data leading to these conclusions, and discuss their relevance to human conditions.