A peptide analogue of thrombin receptor-activating peptide inhibits thrombin and thrombin-receptor-activating peptide-induced vascular smooth muscle cell proliferation

Therapeutic Effects of Breviscapine in Cardiovascular Diseases: A Review

Breviscapine is a crude extract of several flavonoids of Erigeron breviscapus (Vant.) Hand.-Mazz., containing more than 85% of scutellarin, which has been traditionally used in China as an activating blood circulation medicine to improve cerebral blood supply. Accumulating evidence from various in vivo and in vitro studies has shown that breviscapine exerts a broad range of cardiovascular pharmacological effects, including vasodilation, protection against ischaemia/reperfusion (I/R), anti-inflammation, anticoagulation, antithrombosis, endothelial protection, myocardial protection, reduction of smooth muscle cell migration and proliferation, anticardiac remodeling, antiarrhythmia, blood lipid reduction, and improvement of erectile dysfunction. In addition, several clinical studies have reported that breviscapine could be used in conjunction with Western medicine for cardiovascular diseases (CVDs) including coronary heart disease, myocardial infarction, hypertension, atrial fibrillation, hyperlipidaemia, viral myocarditis, chronic heart failure, and pulmonary heart disease. However, the protective effects of breviscapine on CVDs based on experimental studies along with its underlying mechanisms have not been reviewed systematically. This paper reviewed the underlying pharmacological mechanisms in the cardioprotective effects of breviscapine and elucidated its clinical applications.

HVEM signalling promotes colitis

BACKGROUND

Tumor necrosis factor super family (TNFSF) members regulate important processes involved in cell proliferation, survival and differentiation and are therefore crucial for the balance between homeostasis and inflammatory responses. Several members of the TNFSF are closely associated with inflammatory bowel disease (IBD). Thus, they represent interesting new targets for therapeutic treatment of IBD.

METHODOLOGY/PRINCIPAL FINDINGS

We have used mice deficient in TNFSF member HVEM in experimental models of IBD to investigate its role in the disease process. Two models of IBD were employed: i) chemical-induced colitis primarily mediated by innate immune cells; and ii) colitis initiated by CD4(+)CD45RB(high) T cells following their transfer into immuno-deficient RAG1(-/-) hosts. In both models of disease the absence of HVEM resulted in a significant reduction in colitis and inflammatory cytokine production.

CONCLUSIONS

These data show that HVEM stimulatory signals promote experimental colitis driven by innate or adaptive immune cells.

[Proteoglycan as a key molecule in atherosclerosis progression: characteristics of the structure and regulation of the synthesis]

Proteoglycans are macromolecules comprising a core protein and one or more glycosaminoglycan side chains. The macromolecules particularly derived from vascular smooth muscle cells accumulate in atherosclerotic vascular wall and are involved in the progression of vascular lesions. However, the functions of proteoglycans depend on the type of core proteins and microstructure of glycosaminoglycan chains, suggesting importance of the regulation of proteoglycan synthesis in vascular smooth muscle cells. Although the regulation of glycosaminoglycan chain formation is not clear, core protein synthesis is regulated by growth factors/cytokines, mechanical strain, coagulation factors, and other factors. Recently, we found that adiponectin, an adipose-specific plasma protein that exhibits antiatherogenic activities, regulates proteoglycan synthesis in vascular smooth muscle cells.

Protease-Activated Receptor-1 (Thrombin Receptor) Is Expressed in Mesenchymal Portions of Human Hair Follicle

Protease nexin-1, a serine protease inhibitor, is expressed specifically in the dermal papilla (DP) of anagen hair follicles and is suggested to be one of the modulators of the cyclic growth of hair follicles. Accumulating evidence has shown that protease nexin-1 plays its biologic role by inhibiting thrombin action in various systems other than the hair follicle. Thrombin has various physiologic functions including blood coagulation cascade, mostly via activation of protease-activated receptors (PAR). In this study, we investigated the expression of PAR mRNA using RT-PCR in dissected human hair follicles. We showed that PAR-1 mRNA was expressed specifically in the mesenchymal portions, including DP and connective tissue sheath, of anagen hair follicles. Furthermore, immunoreactivity for PAR-1 was detected in the DP and lower portion of connective tissue sheath in the anagen and catagen phases and in the DP of telogen hair follicles. Because only a pharmacologic level (100 nM) of thrombin significantly stimulated cell proliferation and DNA synthesis of the cultured dermal papilla cells, thrombin does not seem to have a mitogenic effect on dermal papilla cells physiologically. These results raise the possibility that thrombin is involved in the cyclic hair growth through its receptor of PAR-1.