Tanshinone II A Attenuates TNF-α-Induced Expression of VCAM-1 and ICAM-1 in Endothelial Progenitor Cells by Blocking Activation of NF-κB.

BACKGROUND/AIMS: Tanshinone IIA (Tan IIA) is effective in the treatment of inflammation and atherosclerosis. The adhesion of inflammatory cells to vascular endothelium plays important role in atherogenic processes. This study examined the effects of Tan IIA on expression of adhesion molecules in tumor necrosis factor-α (TNF-α)-induced endothelial progenitor cells (EPCs). METHODS: EPCs were pretreated with Tan IIA and stimulated with TNF-α. Mononuclear cell (MNC) adhesion assay was performed to assess the effects of Tan IIA on TNF-α-induced MNC adhesion. Expression of vascular cell adhesion molecule-1 (VCAM-1)/intracellular adhesion molecule-1 (ICAM-1) and activation of Nuclear factor κB (NF-κB) signaling pathway were measured. RESULTS: The results showed that the adhesion of MNCs to TNF-α-induced EPCs and expression of VCAM-1/ICAM-1 in EPCs were promoted by TNF-α, which were reduced by Tan IIA. TNF-α increased the amount of phosphorylation of NF-κB, IκB-α and IKKα/ß in cytosolic fractions and NF-κB p65 in nucleus, while Tan IIA reduced its amount. CONCLUSION: This study demonstrated a novel mechanism for the anti-inflammatory/anti-atherosclerotic activity of Tan IIA, which may involve down-regulation of VCAM-1 and ICAM-1 through partial blockage of TNF-α-induced NF-κB activation and IκB-α phosphorylation by the inhibition of IKKα/ß pathway in EPCs.

Ox-LDL can enhance the interaction of mice natural killer cells and dendritic cells via the CD48-2B4 pathway.

The importance of the interaction between natural killer (NK) cells and dendritic cells (DCs) in the expansion of antiviral and antitumor immune responses is well documented; however, limited information on NK/DC interaction during atherosclerosis is available. Inflammation plays an important role in the development of atherosclerosis, and oxidized low-density lipoprotein (ox-LDL) is believed to play a critical role in the development and progression of atherosclerosis. In this study, we developed a NK/DC coculture system to examine the role of ox-LDL in modulating the interaction of mice NK cells and DCs. Fresh NK cells were cocultured with DCs in the absence or presence of ox-LDL. We examined the cytokines released during the interaction. This report provides the first evidence of an enhancement effect by ox-LDL on the NK/DC crosstalk. Notably, we found that ox-LDL significantly promoted the interaction of NK cells and DCs via CD48-2B4 contact-dependent mechanisms. These findings highlight the importance of NK/DCs crosstalk in atherosclerosis and provide new information about the possible mechanisms of atherosclerosis.

[Sero-epidemiologic investigation on tick-borne diseases of humans and domestic animals in Zhejiang province].

OBJECTIVE: To investigate the seroprevalence of tick-borne diseases in humans and domestic animals from rural areas of Zhejiang province. METHODS: Anji county, Jindong district and Tiantai county were selected for samples collection according to their geographic locations and historical prevalence of tick-borne diseases. Blood samples of humans and domestic animals were collected in the three sites. An indirect immuno-fluorescent antibody test was used to determine the presence of IgG antibodies of Rickettsiae heilongjiangii, Orientia tsutsugamushi, R. typhi, Anaplasma phagocytosis, Ehrlichia chaffeensis, Bartonella, R. hainan and Coxiella burnetii in these samples. RESULTS: Six hundred and eighty-three blood samples including 579 from humans and 104 from domestic animals (53 from cattles and 51 from sheep) were collected from the three sites. Antibody positive rates of Orientia tsutsugamushi, R. typhi, Ehrlichia chaffeensis and Coxiella burnetii were significantly different between these sites. IgG from all the 8 pathogens were detected in samples from humans. It was found that the sero-prevalence rates of R. typhi, Bartonella and C. burnetii (20.7%, 10.9%, 5.5%) of adults were higher than those of other Rickettsiae under investigation. The seroprevalence of R. typhi increased along with age. IgG from the 7 pathogens were detected in samples from domestic animals except for Anaplasma phagocytosis. The sero-prevalence rates of R. typhi, Bartonella and R. hainan (69.2%, 51.0%, 22.1%) of adults were higher than those of other Rickettsiae investigated. CONCLUSION: Tick-borne diseases did spread widely in humans and domestic animals from different rural areas of Zhejiang province. The sero-prevalence rates of R. typhi, B. henselae, R. hainan and C. burnetii were higher than that from other pathogens.