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The expression of inflammatory cytokines on vascular walls is a critical event in vascular diseases and inflammation. The aim of the present study was to examine the effects of an extract of Ganoderma lucidum (Reishi) polysaccharides (EORPs), which is effective against immunological disorders, on interleukin- (IL-) 1β expression by human aortic smooth muscle cells (HASMCs) and the underlying mechanism. The lipopolysaccharide- (LPS-) induced IL-1β expression was significantly reduced when HASMCs were pretreated with EORP by Western blot and immunofluorescent staining. Pretreatment with 10 μg/mL EORP decreased LPS-induced ERK, p38, JNK, and Akt phosphorylation. But the increase in IL-1β expression with LPS treatment was only inhibited by pretreatment with the ERK1/2 inhibitor, while the JNK and p38 inhibitors had no effect. In addition, EORP reduced the phosphorylation and nuclear translocation of nuclear factor- (NF-) κB p65 in LPS-treated HASMCs. Furthermore, in vivo, IL-1β expression was strongly expressed in thoracic aortas in LPS-treated mice. Oral administration of EORP decreased IL-1β expression. The level of IL-1β expression in LPS-treated or in LPS/EORP-treated group was very low and was similar to that of the saline-treated group in toll-like receptor 4-deficient (TLR4-/-) mice. These findings suggest that EORP has the anti-inflammatory property and could prove useful in the prevention of vascular diseases and inflammatory responses. [ABSTRACT FROM AUTHOR]

Background aims. We tested the hypothesis that sitagliptin is capable of increasing blood flow in the rat critical limb ischemia (CU) model by enhancement of angiogenesis. Methods. Adipose tissue from adult-male Fischer 344 rats (n = 6) were cultured in endothelial progenitor cell culture medium for 14 d with (25 μmol/L) or without sitagliptin. CLI was induced by ligation of the left femoral artery. Rats (n = 32) were equally separated into four groups: untreated controls (group 1), sitagliptin (4 mg/kg per day; group 2), CLI (group 3) and CLI with sitagliptin (group 4). Results. In vitro, 7 and 14 d after cell culture, endothelial progenitor cell biomarkers assessed by flow cytometry (Sca-l/CD31+, CXCR4+, c-kit+ and CD34+ cells) and Western blot (vascular endothelial growth factor, CXCR4 and stromal-derived factor [SDF]-1α) were remarkably higher in group 4 than in the other groups (all P < 0.01). In vivo, 2 and 14 d after the CLI procedure, circulating angiogenic cell (Sca-1/CD31+, Sca-l+ and CD31+) numbers were significantly higher in group 4 than in the other groups (all P < 0.00 1). Additionally, the messenger RNA and protein expression of angiogenic biomarkers (CXCR4, SDF-1α and vascular endothelial growth factor), immunofluorescent staining of angiogenic cells (CXCR4+, SDF-1α+, CD3 1+, von Willebrand factor + cells) and immunohistochemical staining of small vessel numbers in the ischemic area were significantly higher in group 4 than in the other groups (all P < 0.01). Furthermore, laser Doppler showed that the ratio of ischemic/normal blood flow was remarkably higher group 4 than in group 3 by days 14 and 28 after the CLI procedure (all P < 0.01). Conclusions. Sitagliptin therapy enhances circulating angiogenic cell numbers, angiogenesis and blood flow in the CLI area. [ABSTRACT FROM AUTHOR]