Giada Dogliotti

Molecular basis of anti-inflammatory action of platelet-rich plasma on human chondrocytes: mechanisms of NF-κB inhibition via HGF.

Loss of articular cartilage through injury or disease presents major clinical challenges also because cartilage has very poor regenerative capacity, giving rise to the development of biological approaches. As autologous blood product, platelet‐rich plasma (PRP) provides a promising alternative to surgery by promoting safe and natural healing. Here we tested the possibility that PRP might be effective as an anti‐inflammatory agent, providing an attractive basis for regeneration of articular cartilage, and two principal observations were done. First, activated PRP in chondrocytes reduced the transactivating activity of NF‐κB, critical regulator of the inflammatory process, and decreased the expression of COX‐2 and CXCR4 target genes. By analyzing a panel of cytokines with different biological significance, in activated PRP we observed increases in hepatocyte growth factor (HGF), interleukin‐4 and tumor necrosis factor‐α (TNF‐α). HGF and TNF‐α, by disrupting NF‐κB‐transactivating activity, were important for the anti‐inflammatory function of activated PRP. The key molecular mechanisms involved in PRP‐inhibitory effects on NF‐κB activity were for HGF the enhanced cellular IkBα expression, that contributed to NF‐κB‐p65 subunit retention in the cytosol and nucleo‐cytoplasmic shuttling, and for TNF‐α the p50/50 DNA‐binding causing inhibition of target‐gene expression. Second, activated PRP in U937‐monocytic cells reduced chemotaxis by inhibiting chemokine transactivation and CXCR4‐receptor expression, thus possibly controlling local inflammation in cartilage. In conclusion, activated PRP is a promising biological therapeutic agent, as a scaffold in micro‐invasive articular cartilage regeneration, not only for its content of proliferative/differentiative growth factors, but also for the presence of anti‐inflammatory agents including HGF. J. Cell. Physiol. 225: 757–766, 2010.

Relation of Echocardiographic Epicardial Fat Thickness and Myocardial Fat

Epicardial and myocardial fats increase with degree of visceral adiposity and possibly contribute to obesity-associated cardiac changes. Echocardiographic epicardial fat thickness is a new and independent marker of visceral adiposity. The aim of this study was to test whether echocardiographic epicardial fat is related to myocardial fat. Twenty consecutive Caucasian men (body mass index 30.5 +/- 2 kg/m(2), 42 +/- 7 years of age) underwent transthoracic echocardiography for epicardial fat thickness, morphologic and diastolic parameter measurements, hydrogen-1 magnetic resonance spectroscopy for myocardial fat quantification, and magnetic resonance imaging for epicardial fat volume estimation. Hydrogen-1 magnetic resonance spectroscopic myocardial fat content, magnetic resonance imaging of epicardial fat volume, and echocardiographic epicardial fat thickness range varied from 0.5% to 31%, 4.5 to 43 ml, and 3 to 15 mm, respectively. Myocardial fat content showed a statistically significant correlation with echocardiographic epicardial fat thickness (r = 0.79, p <0.01), waist circumference (r = 0.64, p <0.01), low-density lipoprotein cholesterol (r = 0.54, p <0.01), plasma adiponectin levels (r = -0.49, p <0.01), and isovolumic relaxation time (r = 0.59, p <0.01). However, multivariate linear regression analysis showed epicardial fat thickness as the most significant independent correlate of myocardial fat (p <0.001). Although this study is purely correlative and no causative conclusions can be drawn, it can be postulated that increased echocardiographic epicardial fat accumulation could reflect myocardial fat in subjects with a wide range of adiposity.

The natural antioxidant alpha-lipoic acid induces p27Kip1-dependent cell cycle arrest and apoptosis in MCF-7 human breast cancer cells

Unlike normal cells, tumor cells survive in a specific redox environment where the elevated reactive oxygen species contribute to enhance cell proliferation and to suppress apoptosis. Alpha-lipoic acid, a naturally occurring reactive oxygen species scavenger, has been shown to possess anticancer activity, due to its ability to suppress proliferation and to induce apoptosis in different cancer cell lines. Since at the moment little information is available regarding the potential effects of alpha-lipoic acid on breast cancer, in the present study we addressed the question whether alpha-lipoic acid induces cell cycle arrest and apoptosis in the human breast cancer cell line MCF-7. Moreover, we investigated some molecular mechanisms which mediate alpha-lipoic acid actions, focusing on the role of the PI3-K/Akt signalling pathway. We observed that alpha-lipoic acid is able to scavenge reactive oxygen species in MCF-7 cells and that the reduction of reactive oxygen species is followed by cell growth arrest in the G1 phase of the cell cycle, via the specific inhibition of Akt pathway and the up-regulation of the cyclin-dependent kinase inhibitor p27(kip1), and by apoptosis, via changes of the ratio of the apoptotic-related protein Bax/Bcl-2. Thus, the anti-tumor activity of alpha-lipoic acid observed in MCF-7 cells further stresses the role of redox state in regulating cancer initiation and progression.

Why menisci show higher healing rate when repaired during ACL reconstruction? Growth factors release can be the explanation

PurposeHealing rate of meniscus repair is higher when the suture is associated with anterior cruciate ligament reconstruction. A possible explanation can be a different pattern of release of growth factors between anterior cruciate ligament reconstruction and isolated meniscus surgery. Hypothesis of this study is that the concentrations of bFGF, TGF-β and platelet-derived growth factor (PDGF) in joint fluid, immediately after single-bundle anterior cruciate ligament reconstruction and arthroscopic partial meniscectomy, can be different.MethodsTwenty consecutive patients underwent partial medial meniscectomy and twenty consecutive patients underwent single-bundle anterior cruciate ligament reconstruction with hamstring grafts were enrolled in the study. Thirty minutes after the end of the surgical procedure, a sample of joint fluid, as well of venous blood, was collected from all the patients. Concentrations of growth factors were determined by enzyme-linked immunosorbent assay.ResultsThe peripheral blood concentration of TGF-β, bFGF and PDGF was comparable between partial meniscectomy and anterior cruciate ligament reconstruction groups. No differences between the two surgical techniques were also found in term of TGF-β and bFGF joint fluid concentration, whereas joint PDGF concentration of anterior cruciate ligament reconstruction patients was significantly higher than the one found in partial meniscectomy patients.ConclusionsA significant growth factors release was detected in the knee joint during arthroscopic surgery. PDGF concentration was significantly higher in anterior cruciate ligament reconstructed knee than in the meniscectomy group. PDGF can play an important role enhancing the healing response of meniscus suture and can be one of the biological reasons of the higher meniscal healing rate in anterior cruciate ligament reconstructed knee.

Oxidative Stress and Antioxidant Status in Patients with Erectile Dysfunction

INTRODUCTION Erectile dysfunction (ED) is increasingly recognized as a public health problem. The interaction between nitric oxide and reactive oxygen species is one of the important mechanisms implicated in the pathophysiological process of ED. Plasma contains various antioxidant components to prevent free-radical injury. AIM The aim of this study was to determine and compare the oxidative and antioxidant status of peripheral venous blood in patients with ED of arteriogenic and non-arteriogenic origin. METHODS Oxidative stress and antioxidant status were assessed in 40 patients with ED and 20 healthy controls. MAIN OUTCOME MEASURES Plasma reactive oxygen metabolite (ROM) concentrations were measured as an indicator of oxidative stress, and plasma total antioxidant status (TAS) to indicate antioxidant defense. RESULTS Plasma ROM concentrations were higher (349.75 +/- 53.35 standard deviation [SD] U.Carr vs. 285.43 +/- 25.58 U.Carr, P < 0.001) and plasma TAS lower (0.54 +/- 0.16 SD mmol/L vs. 0.94 +/- 0.28 SD mmol/L, P < 0.0001) in patients with arteriogenic ED in comparison to those in patients with non-arteriogenic ED. Plasma ROM and TAS in controls were not significantly different from those in non-arteriogenic ED. Conclusions. This observation may be useful to better understand and distinguish arteriogenic from non-arteriogenic ED using laboratory tests. In addition, our findings provide important support for an antioxidant therapy to try to correct oxidative stress in arteriogenic ED patients.

Age-related changes in plasma levels of BDNF in Down syndrome patients

BackgroundThe prevalence of coronary artery diseases is low among Down Syndrome (DS) patients and they rarely die of atherosclerotic complications. Histopathological investigations showed no increase in atherosclerosis, or even a total lack of atherosclerotic changes, in DSAimThe aim of our study is to investigate the relationship between age and brain-derived neurotrophic factor (BDNF) levels in Down Syndrome (DS).Subjects and methodsThree groups of DS patients were studied: the first consisted of 23 children (age 2-14 years); the second of 14 adults (age 20-50 years), the third group of 13 elderly persons (>60 years) and a controls group of 20 healthy patients (age 15-60 years).The analytes of interest were quantified using a biochip array analyzer (Evidence®, Randox Ltd., Crumlin, UK).ResultsPlasma BDNF was higher in DS patients than in controls and there was a significant age-related increase. Serum levels of IL-6 and MCP-1 were also higher in DS children and adults, but not in older patients, than in healthy control. High levels of circulating BDNF may protect DS patients from the clinical complications of atherosclerosis. However, the striking drop in peripheral BDNF levels with age might predispose these patients to clinical manifestations of dementia in later life.

Serum Amyloid A and C-Reactive Protein Independently Predict the Recurrences of Atrial Fibrillation After Cardioversion in Patients With Preserved Left Ventricular Function

BACKGROUND Subclinical inflammation and atrial stretch have been recognized as important contributors to atrial fibrillation (AF) onset and perpetuation. The aim of the study was to compare the predictive role of serum inflammatory markers (serum amyloid A [SAA], and C-reactive protein [CRP]) and N-terminal pro brain natriuretic peptide (NT-proBNP) an indice of atrial strain in relation to subacute arrhythmic recurrence rate in patients with persistent AF and normal left ventricular ejection fraction (LVEF). METHODS We studied 57 patients with a mean LVEF of 58.7 ± 6%. NT-proBNP, SAA and CRP levels were determined few hours before electrical cardioversion and 3 weeks after cardioversion. RESULTS Subacute AF recurrences were documented in 19 (33 %) patients. Whereas NT-proBNP levels did not predict arrhythmic outcome, higher SAA (> 6.16-6.19 mg/L) and CRP levels (> 2.99-3.10 mg/L) were significantly associated with AF recurrences (odds ratio [OR], 5.39; 95% confidence interval [CI], 1.59-18.26; P = 0.007 and OR, 14.93; 95% CI, 3.90-57.19; P < 0.001). Both SAA (OR, 18.29; 95% CI, 2.07-161.46; P = 0.009) and high sensitivity CRP (OR, 42.03; 95% CI, 4.83-365.45; P = 0.001) through the multivariate logistic regression analysis show an independent role in predicting the AF recurrence with a sensitivity of 100% (38/38) and a specificity of 52.6% (10/19). CONCLUSIONS The present study demonstrates that in patients with persistent AF and preserved LVEF, SAA and CRP levels are independent predictors of AF subacute recurrence rate, whereas NT-proBNP, not associated with arrhythmic outcome, reflects the hemodynamic alterations secondary to arrhythmia presence. The simultaneous determination of SAA and high sensitivity CRP has a very high sensitivity (100%) in predicting the AF recurrence.

Serum adhesion molecules in acute pancreatitis: Time course and early assessment of disease severity

Objectives: To evaluate the adhesion molecule time course in the early phases of acute pancreatitis and to explore the usefulness of these proteins in assessing the severity of the disease. Fifteen consecutive acute pancreatitis patients (10 patients with the mild and 5 with the severe disease) admitted to the hospital within 6 hours after the onset of pain and 15 age- and sex-matched healthy subjects. Methods: Vascular cell adhesion molecule 1, intercellular adhesion molecule 1, E-selectin, P-selectin, and L-selectin were quantified on hospital admission and for the following 2 days. Results: Acute pancreatitis patients had vascular cell adhesion molecule 1 and P-selectin concentrations significantly lower and L-selectin concentrations significantly higher than the healthy subjects. Only E-selectin was significantly higher in severe than in mild disease (P = 0.029); a value of E-selectin ranging from 3.83 to 3.92 ng/mL was the best cutoff value for differentiating severe from mild acute pancreatitis (sensitivity: 60.0%, specificity: 90.0%, cases correctly classified: 80%). E-selectin and P-selectin entered the multivariate logistic regression analysis, and a score was calculated showing a sensitivity of 93.3% and a specificity of 86.7% in identifying the patients with severe pancreatitis. Conclusions: This score seems to be useful for the early assessment of the severity of acute pancreatitis.Abbreviations: VCAM-1 - vascular cell adhesion molecule 1, ICAM-1 - intercellular adhesion molecule 1

Reduced plasma levels of P-selectin and L-selectin in a pilot study from Alzheimer disease: relationship with neuro-degeneration

Neurodegenerative processes associated with Alzheimer’s disease (AD) are accompanied by reactive astrogliosis and microglia activation and a role for chronic inflammation in the brain degeneration of these patients has been suggested. Moreover impaired immune functions in AD brains might also influence the disease’s progression. Therefore, it is of interest to further characterized inflammatory molecules in the peripheral blood of patients with AD and its relationship with cognitive decline. A complex picture emerged in this pilot study and IL-8, IFN-gamma, MCP-1 and VEGF levels were increased in AD. Levels of P-selectin and L-selectin were decreased in AD and lowest in AD patients with highest cognitive decline. Our findings suggest that these molecules may induce alterations of endothelial regulation and influence neurodegenerative processes of AD.

Adipocytokines in Down's syndrome, an atheroma-free model: Role of adiponectin

Downs syndrome (DS) is the most frequent chromosomal aberration in men. Moreover DS is considered an atheroma-free model. Plasma levels of interleukin-6 (IL-6), tumor necrosis factor-alpha high sensitivity (hsTNF-alpha), leptin and adiponectin from non-demented DS subjects of three different age cohorts (2-14, 20-50 and above 60 years) and healthy controls were measured. No clinical and sub-clinical inflammation was apparent in DS patients. Plasma levels of hsTNF-alpha, IL-6 and leptin were higher in children than in adult and old DS subjects. Instead, serum levels of adiponectin were increased in older DS patients than in DS children and adults. High levels of circulating adiponectin might protect DS from clinical complications of atherosclerosis.