Olive leaf extract (OLE) is used in traditional medicine as a food supplement and as an over-the-counter drug for a variety of its effects, including anti-inflammatory and anti-atherosclerotic ones. Mechanisms through which OLE could modulate these pathways in human vasculature remain largely unknown. Serum amyloid A (SAA) plays a causal role in atherosclerosis and cardiovascular diseases and induces pro-inflammatory and pro-adhesive responses in human coronary artery endothelial cells (HCAEC). Within this study we explored whether OLE can attenuate SAA-driven responses in HCAEC. HCAEC were treated with SAA (1,000 nM) and/or OLE (0.5 and 1 mg/ml). The expression of adhesion molecules VCAM-1 and E-selectin, matrix metalloproteinases (MMP2 and MMP9) and microRNA 146a, let-7e, and let-7g (involved in the regulation of inflammation) was determined by qPCR. The amount of secreted IL-6, IL-8, MIF, and GRO-α in cell culture supernatants was quantified by ELISA. Phosphorylation of NF-κB was assessed by Western blot and DNA damage was measured using the COMET assay. OLE decreased significantly released protein levels of IL-6 and IL-8, as well as mRNA expression of E-selectin in SAA-stimulated HCAEC and reduced MMP2 levels in unstimulated cells. Phosphorylation of NF-κB (p65) was upregulated in the presence of SAA, with OLE significantly attenuating this SAA-induced effect. OLE stabilized SAA-induced upregulation of microRNA-146a and let-7e in HCAEC, suggesting that OLE could fine-tune the SAA-driven activity of NF-κB by changing the microRNA networks in HCAEC. SAA induced DNA damage and worsened the oxidative DNA damage in HCAEC, whereas OLE protected HCAEC from SAA- and H 2 O 2 -driven DNA damage. OLE significantly attenuated certain pro-inflammatory and pro-adhesive responses and decreased DNA damage in HCAEC upon stimulation with SAA. The reversal of SAA-driven endothelial activation by OLE might contribute to its anti-inflammatory and anti-atherogenic effects in HCAEC.

Efficient stent implantation among others depends on avoiding the aggregation of platelets in the blood vessels and appropriate proliferation of endothelial cells and controlled proliferation of smooth muscle cells, which reduces the development of pathology, such as neointimal hyperplasia, thrombosis, and restenosis. The current article provides an elegant solution for prevention of platelet and smooth muscle cell adhesion and activation on stent surfaces while obtaining surface conditions to support the growth of human coronary artery endothelial cells. This was achieved by surface nanostructuring and chemical activation of the surface. Specific nanotopographies of titanium were obtained by electrochemical anodization, while appropriate chemical properties were attained by treatment of titanium oxide nanotubes by highly reactive oxygen plasma. Surface properties were studied by scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. Wettability was evaluated by measuring the water contact angle. The influence of nanostructured morphology and plasma modification on in vitro biological response with human coronary artery endothelia and smooth muscle cells as well as whole blood was studied. Our results show that a combination of nanostructuring and plasma modification of the surfaces is an effective way to achieve desired biological responses necessary for implantable materials such as stents.

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Inflammation in systemic sclerosis (SSc) is a prominent, but incompletely characterized feature in early stages of the disease. The goal of these studies was to determine the circulating levels, clinical correlates and biological effects of the acute phase protein serum amyloid A (SAA), a marker of inflammation, in patients with SSc. Circulating levels of SAA were determined by multiplex assays in serum from 129 SSc patients and 98 healthy controls. Correlations between SAA levels and clinical and laboratory features of disease were analyzed. The effects of SAA on human pulmonary fibroblasts were studied ex vivo. Elevated levels of SAA were found in 25% of SSc patients, with the highest levels in those with early-stage disease and diffuse cutaneous involvement. Significant negative correlations of SAA were found with forced vital capacity and diffusion capacity for carbon monoxide. Patients with elevated SAA had greater dyspnea and more frequent interstitial lung disease, and had worse scores on patient-reported outcome measures. Incubation with recombinant SAA induced dose-dependent stimulation of IL-6 and IL-8 in normal lung fibroblasts in culture. Serum levels of the inflammatory marker SAA are elevated in patients with early diffuse cutaneous SSc, and correlate with pulmonary involvement. In lung fibroblasts, SAA acts as a direct stimulus for increased cytokine production. These findings suggest that systemic inflammation in SSc may be linked to lung involvement and SAA could serve as a potential biomarker for this complication.

Inflammation is considered to be the driving force leading to atherogenic and atherosclerotic mechanisms. Increased levels of SAA predict the risk of coronary artery disease and even mortality from cardiovascular disease in humans. Recent animal and human studies have indicated that SAA plays a causal role in atherogenesis, although it is largely unclear how this occurs. The objectives of this study are to understand the role of SAA in activating possible atherogenic inflammatory responses in human coronary artery endothelial cells (HCAEC) and to compare them with human umbilical vein endothelial cells (HUVEC). Our hypothesis is that vein and artery endothelial cells have different expression patterns and levels, leading to differential inflammatory responses. HUVEC and HCAEC were grown in order to analyze the effects of SAA on endothelial expression of pro-inflammatory cytokines, such as IL-6, chemokines, such as IL-8, and adhesion molecules (s-ICAM, s-VCAM, E-selectin) by reverse transcription-PCR and ELISAs. We compared the dose responses of SAA between HUVEC and HCAEC. SAA activated both HUVEC and HCAEC pro-inflammatory factors in a dose-dependent manner. In comparison however, HCAEC showed a strikingly greater sensitivity to SAA, with a higher level of expression of all pro-inflammatory markers at much lower concentrations of SAA, and their much greater stimulation at higher SAA concentrations. SAA also generated a dose-dependent positive feedback response on its own mRNA expression in HCAEC as compared to HUVEC. In summary, there are distinct significant differences in the levels of inflammatory markers and adhesion molecules between HUVEC and HCAEC SAA induced dose responses that could potentially account for HCAEC greater susceptibility to inflammation and atherogenesis.Inflammation is known to be a major driving force in atherogenesis and in the initiation of coronary plaque formation (l). Cohort studies have reported that acute inflammatory parameters [such as C-reactive protein (CRP) or serum amyloid A (SAA)], cellular adhesion molecules, cytokines and chemokines are all elevated among patients at risk for future coronary occlusion (2-4). Increased SAA levels predict the risk of coronary artery disease in humans (5) and multivariate studies have identified SAA as an independent predictor of mortality in acute myocardial infarction patients (6). Recent animal and human studies indicate that SAA plays a causal role in atherogenesis (7), however it is largely unclear how the induced SAA play this role.The endothelium is heterogeneous due to its