Folia Pharmacologica Japonica最新文献

Acute phase proteins such as CRP, amyloid protein A, and α1-antitrypsin are produced in the liver and their plasma levels are increased during the acute inflammatory response. In contrast, there are plasma proteins whose dynamics are opposite to acute phase proteins. This group includes histidine-rich glycoprotein (HRG), inter-α-inhibitor proteins, albumin, and transthyretin. HRG binds to a variety of factors and regulates the fundamental processes; the blood coagulation, the clearance of apoptotic cells, and tumor growth. In the present review, we focus on the anti-septic effects of HRG in mice model, the actions of HRG on human blood cells/vascular endothelial cells, and the identification of a novel receptor CLEC1A for HRG, based on our recent findings. HRG appears to maintain the quiescence of neutrophils; a round shape, the low levels of spontaneous release of ROS, the ease passage through artificial microcapillaries, and prevention of adhesion to vascular endothelial cells. HRG also inhibited activation of vascular endothelial cells; the suppression of adhesion molecules and the inhibition of HMGB1 mobilization and cytokine secretion. It was shown that plasma HRG level was an excellent biomarker of septic patients in ICU for the evaluation of severity and prognosis. So far little attention has been paid to HRG in terms of a functional role in sepsis and ARDS, however, it is strongly suggested that HRG may be an important plasma factor that prevents a progress in the septic cascade and maintains the homeostasis of blood cells and vascular endothelial cells.

Basophils are the rarest granulocytes representing less than 1% of peripheral blood leukocytes. Even though basophils have been discovered more than 140 years ago, their roles in immune reactions had long been an enigma, partly because of their rarity and the similarity to tissue-resident mast cells. However, recent development of the analytical tools for basophil research, such as basophil-depletion antibody and basophil-related engineered mice, has uncovered the unique roles of basophils in various immune reactions. Basophils are now appreciated as a critical immune cell in various type 2-immune responses including the induction of chronic allergic inflammation and protective immunity against parasites. In this review, we summarize the recent understandings in the roles of basophils in allergic inflammation with especial focus on skin inflammation. We then focus on our recent findings in the differentiation and maturation pathways of basophils.

Major depressive disorder (MDD) is a psychiatric disorder that affects more than 300 million people worldwide and has a serious impact on society. Conventional antidepressants targeting monoamines in the brain based on the monoamine hypothesis are known to take a prolonged time to be effective or less effective in 30% of MDD patients. Hence, there is a need to develop antidepressants that are effective against treatment-resistant depression and have a new mechanism different from the monoamine hypothesis. An increasing number of research groups including us have been establishing that pituitary adenylate cyclase-activating polypeptide (PACAP) and one of its receptors, PAC1 receptor, are closely related to the etiology of stress-related diseases such as MDD. Therefore, it is strongly suggested that the PAC1 receptor is a promising target in the treatment of psychiatric disorders. We developed a novel, non-peptidic, small-molecule, high-affinity PAC1 receptor antagonists and conducted behavioral pharmacology experiments in mice to characterize a novel PAC1 receptor antagonist as a new option for MDD therapy. The results show that our novel PAC1 receptor antagonist has the potential to be a new antidepressant with a high safety profile. In this review, we would like to present the background of developing our novel PAC1 receptor antagonist and its effects on mouse models of acute stress.

In drug discovery and pharmacological research, early identification of target molecules for compounds with pharmacological effects is crucial. However, this process often requires significant effort and can be rate-limiting, thereby slowing down research progress. This paper introduces a simplified and rapid method for quick screening of binding compounds or proteins. Utilizing Affinity Selection Mass Spectrometry (ASMS), this technique efficiently detects compound-target binding through size-exclusion chromatography and mass spectrometry. ASMS offers high sensitivity and specificity, making it ideal for accurate identification of binding interactions. We have further enhanced ASMS to handle membrane proteins without solubilization, creating Binder Selection Technology (BST). BST allows screening against both soluble and challenging membrane proteins such as GPCRs and SLC transporters. By using cell membrane fractions or organelle fractions with high target molecule expression, BST efficiently identifies potential binding compounds. This innovative method constructs a comprehensive database of binding compounds for various targets, facilitating rapid hypothesis testing and pharmacological evaluation. Additionally, BST screens 17,000 proteins, including membrane proteins, using wheat germ cell-free and animal cell expression systems. This approach allows exploration of binding interactions without labeling compounds or immobilizing proteins, preserving their native state. BST is powerful for identifying targets of compounds with known pharmacological effects but unknown targets in animal or cell-based assays. By utilizing BST, researchers can overcome bottlenecks in early drug discovery, significantly enhancing research speed and success rates. This method represents a major advancement, providing an efficient and effective way to identify and validate target molecules in drug discovery.

Lecanemab is a new anti-amyloid antibody being developed as a treatment for Alzheimer's disease. It is expected to delay the progression of the disease by reducing the accumulation of amyloid beta (Aβ) in the brain. However, no drug has been developed that can completely eliminate Aβ and improve symptoms. A representative Catalytide, JAL-TA9 (YKGSGFRMI), cleaves Aβ42 and improves symptoms in an Alzheimer's disease mouse model, suggesting that JAL-TA9 is a promising candidate for treating Alzheimer's disease by effectively eliminating Aβ. The catalytic center of JAL-TA9 is GSGFR. To identify better Catalytides for Alzheimer's treatment, we analyzed the structure-activity relationship of 21 point-mutated GSGFR derivatives. In this process, we discovered two peptides, GSGFK and GSGNR, that not only inhibit Aβ25-35 aggregation but also dissolve aggregated Aβ25-35. Intracerebroventricular administration of GSGFK protected mice against Aβ25-35-induced short-term memory deficits and promoted microglial phagocytic activity. Like Lecanemab, GSGFK targets Aβ, but it has advantages such as safety, administration method, and cost. In this talk, we will discuss the potential of GSGFK as a therapeutic candidate for Alzheimer's disease.