Mycophenolic acid regulates spleen tyrosine kinase to repress tumour necrosis factor-alpha-induced monocyte chemotatic protein-1 production in cultured human aortic endothelial cells

The Clinical Significance of Salusins in Systemic Sclerosis-A Cross-Sectional Study

Background: Systemic sclerosis (SSc) is a connective tissue disease manifesting with progressive fibrosis of the skin and internal organs. Its pathogenesis is strictly associated with vascular disfunction and damage. Salusin-α and salusin-β, endogenous peptides regulating secretion of pro-inflammatory cytokines and vascular smooth muscle proliferation, may potentially play a role in SSc pathogenesis. Objectives: The aim of this study was to assess the concentration of salusins in sera of patients with SSc and healthy controls and to evaluate correlations between the salusins levels and selected clinical parameters within the study group. Materials and methods: 48 patients with SSc (44 women; mean age, 56.4, standard deviation, 11.4) and 25 adult healthy volunteers (25 women; mean age, 55.2, standard deviation, 11.2) were enrolled. All patients with SSc were treated with vasodilators and twenty-seven of them (56%) also received immunosuppressive therapy. Results: Circulating salusin-α was significantly elevated in patients with SSc in comparison to healthy controls (U = 350.5, p = 0.004). Patients with SSc receiving immunosuppression had higher serum salusin-α concentrations compared with those without immunosuppressive therapy (U = 176.0, p = 0.026). No correlation was observed between salusins concentrations and skin or internal organ involvement parameters. Conclusions: Salusin-α, a bioactive peptide mitigating the endothelial disfunction, was elevated in patients with systemic sclerosis receiving vasodilators and immunosuppressants. Increased salusin-α concertation may be associated with the initiation of atheroprotective processes in patients with SSc managed pharmacologically, which requires verification in future studies.

Immunomodulatory and anti-inflammatory effects of N-acetylcysteine in ovalbumin-sensitized rats

Background

Pro-inflammatory cytokines such as interleukin-5 (IL-5) and tumor necrosis factor-alpha (TNF-α) as well as immunoglobulin-E (IgE) appear to play a role in asthma. N-acetylcysteine (NAC), an antioxidant, might have clinical benefits in asthma prevention. The possible preventive effects of NAC against experimentally induced asthma in rats are investigated. The rats were allocated into five groups: a normal control, asthma control, a standard dexamethasone (DEXA, 1 mg/kg, orally) group, and two NAC groups (300 and 500 mg/kg, orally, respectively). Ovalbumin (OVA) sensitization was used to trigger asthma, which was then followed by an intra-nasal challenge. Test gents were administrated for 14 days before the challenge and during the three challenge days (20, 21, and 22). The tidal volume (TV) and peak expiratory flow rate (PEFR) as respiratory functions were determined. The pro-inflammatory cytokines as IL-5 and TNF-α were evaluated in lung homogenate. Serum IgE and absolute eosinophil count (AEC) in bronchoalveolar lavage fluid (BALF) were measured. In addition, the oxidative markers in lung tissue and nitrosative marker in BALF were assessed; finally, lungs were isolated for histopathological study.

Results

NAC restored lung functions, inhibited the asthma-dependent increase in TNF-α, IL-5, IgE, AEC, nitric oxide, and malondialdehyde levels. NAC further re-established lung glutathione content and superoxide dismutase activity, resulting in milder overall lung pathology.

Conclusions

Experimental bronchial asthma may be protected by NAC. The anti-asthmatic potential of NAC may be explained by its suppressant influence on IgE antibody formation, pro-inflammatory cytokines production, eosinophil infiltration, and oxidative stress.

Identification of novel genes and pathways in carotid atheroma using integrated bioinformatic methods

Atherosclerosis is the primary cause of cardiovascular events and its molecular mechanism urgently needs to be clarified. In our study, atheromatous plaques (ATH) and macroscopically intact tissue (MIT) sampled from 32 patients were compared and an integrated series of bioinformatic microarray analyses were used to identify altered genes and pathways. Our work showed 816 genes were differentially expressed between ATH and MIT, including 443 that were up-regulated and 373 that were down-regulated in ATH tissues. GO functional-enrichment analysis for differentially expressed genes (DEGs) indicated that genes related to the "immune response" and "muscle contraction" were altered in ATHs. KEGG pathway-enrichment analysis showed that up-regulated DEGs were significantly enriched in the "FcεRI-mediated signaling pathway", while down-regulated genes were significantly enriched in the "transforming growth factor-β signaling pathway". Protein-protein interaction network and module analysis demonstrated that VAV1, SYK, LYN and PTPN6 may play critical roles in the network. Additionally, similar observations were seen in a validation study where SYK, LYN and PTPN6 were markedly elevated in ATH. All in all, identification of these genes and pathways not only provides new insights into the pathogenesis of atherosclerosis, but may also aid in the development of prognostic and therapeutic biomarkers for advanced atheroma.

Docosahexaenoic acid decreases TNF-α-induced lectin-like oxidized low-density lipoprotein receptor-1 expression in THP-1 cells

Docosahexaenoic acid (DHA) prevents atherosclerosis and may decrease monocyte/macrophage activation by tumor necrosis factor (TNF)-α. Here, we sought to determine the protective effects of DHA against TNF-α-induced stimulation of lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) expression, which is associated with atherosclerosis. Using reverse transcription polymerase chain reaction, we found that TNF-α induced the expression of LOX-1 (OLR1), NADPH oxidase 2 (Nox2), p47phox (NCF1), very late antigen-4 (ITGA4), and lymphocyte function-associated antigen (ITGAL) genes. Additionally, DHA attenuated TNF-α-induced acetylated (Ac)-LDL uptake and reactive oxygen species (ROS) production, as measured using fluorescently labeled LDL and H2DCFDA, respectively, and reduced the expression levels of these genes. Moreover, the PI3 kinase inhibitor LY294002 blocked these effects of DHA. These results indicated that DHA inhibited several events associated with redox regulation in a PI3K-dependent manner, thereby mediating the expression of LOX-1 in monocytes/macrophages.