Effects of antioxidants and NO on TNF-α-induced adhesion molecule expression in human pulmonary microvascular endothelial cells

SummaryPro-inflammatory cytokines initiate the vascular inflammatory response via upregulation of adhesion molecules on the endothelium. Recent observations suggest that reactive oxygen intermediates may play a pivotal role in TNF-α signaling and upregulate gene expression. We therefore evaluated the effects of pyrrolidine dithiocarbamate (PDTC; 0.1 mM) and spermine NONOate (Sper-NO; 1mM) on adhesion molecule expression and nuclear factor kappa B (NF-κB) activation induced by TNF-α(10ng/ml) in cultured human pulmonary microvascular endothelial cells (PMVEC). Treatment of cells with TNF-α for 4h significantly induced the surface expression of E-selectin and ICAM-1. Treatment with TNF-α for 8h significantly induced the surface expression of E-selectin, ICAM-1 and VCAM-1. The upregulation of these adhesion molecules was suppressed significantly by pretreatment with PDTC or Sper-NO for 1h. 8-Bromo-cyclic GMP (1mM) had no such effect, suggesting that the NO donor's effect was non-cGMP-dependent. The mRNA expression of E-selectin, ICAM-1 and VCAM-1, and activation of NF-κB induced by TNF-α for 2h were decreased significantly by the above two pretreatments. N-acetylcysteine (10mM) and S-nitroso-N-acetylpenicillamine (1mM) had little inhibitory effects on the cell surface and mRNA expression of these adhesion molecules stimulated by TNF-α. Treatment with TNF-α for 4h enhanced HL-60 leukocyte adhesion to human PMVEC, the effect of which was inhibited significantly by pretreatment with PDTC or Sper-NO. These findings indicate that both cell surface and mRNA expression of adhesion molecules in human PMVEC induced by TNF-α are inhibited significantly by pretreatment with PDTC or Sper-NO, possibly in part through blocking the activation of NF-κB. Although our in vitro results cannot be directly extrapolated to the in vivo situation, they suggest a potential therapeutic approach for intervention in cytokine-mediated inflammatory processes in the human lung

Older boys benefit from higher initial prednisolone therapy for nephrotic syndrome

Older boys benefit from higher initial prednisolone therapy for nephrotic syndrome.BackgroundA long course of the initial prednisolone therapy has been shown to be more effective than standard-course therapy in reducing relapse rates in children with idiopathic nephrotic syndrome, but it is commonly accompanied by corticosteroid toxicities. There has been no study on prednisolone dosage for the effective treatment of nephrotic syndrome.MethodsSixty-eight children (42 boys and 26 girls) with an initial attack of nephrotic syndrome were randomly allocated into two different long-course treatment groups. Patients in Group 1 received a daily prednisolone dose of 60 mg/m2 for six weeks, followed by an alternate-day dose of 40 mg/m2 for six weeks. Patients in Group 2 had a daily dose of 40 mg/m2 instead of 60 mg/m2.ResultsFour children in each group did not respond within six weeks. Group 1 was associated with a significantly earlier response but more frequent corticosteroid toxicities than Group 2. Boys in Group 1 had a higher rate of sustained remission than boys in Group 2 (P = 0.0073), especially boys four years old or more (P = 0.0027), but girls did not show a significant difference (P = 0.863). Boys four years old or more in Group 1 had a course of frequent relapsing less often than those in Group 2 (2 of 13 vs. 6 of 8, P = 0.0075).ConclusionThese findings indicate that efficient prednisolone doses may vary between sexes and ages, and that a higher initial prednisolone therapy may be of greater benefit to older boys

Mucosal Immunity and the Onset of Allergic Disease

Mucosal barriers encounter an environment that is rich in pathogens that possess mechanisms for invading mucosal tissues. These barriers also encounter innocuous antigens, such as foods, airborne antigens, and microbiota. The mucosa has developed a sophisticated immune system that can mount robust immune responses against pathogenic antigens, while maintaining mucosal tolerance against non-pathogenic antigens. Accumulating evidence indicates that the mucosal epithelium, dendritic cells, and a subtype of T cells with regulatory properties play important roles in the development and maintenance of mucosal tolerance. Moreover, the micribiota also contribute to regulating the mucosal immune system. A failure to develop or the breakdown of mucosal tolerance can result in allergic diseases, such as food allergy and asthma. By taking advantage of the unique characteristics of the mucosal immune system, strategies that induce regulatory cells in vivo and, thereby, reconstitute mucosal tolerance may be used to develop novel therapies that are suitable for treating or preventing of allergic diseases

Role of dendritic cells in Th1/Th2 balance: A novel therapeutic target of allergic diseases

Considerable evidence supports the role of dendritic cells (DC) in the pathogenesis of allergic diseases. Dendritic cells, as the most potent antigen-presenting cells (APC) for the induction of primary immune response to antigen, are deeply involved in the differentiation of na'i've T cells into Th2 cells, thereby developing the development of allergic sensitization. After sensitization, DC may also function as a major APC to control the activation and clonal expansion of memory Th2 cells. In addition, DC are able to produce chemokines to recruit Th2 cells into inflammatory sites, indicating DC are important agents in various phases of allergic inflammation. Recently, we have demonstrated that monocyte chemotactic protein-1 not only regulates the homing of DC, but also modulates DC function. The present paper reviews the role of DC in the regulation of the Th2 response in allergic diseases and discusses the possibility of a new therapeutic strategy targeting chemokine-mediated regulation of DC function

Carboxyhemoglobin Formation in Preterm Infants Is Related to the Subsequent Development of Bronchopulmonary Dysplasia

Objective. To evaluate the usefulness of carboxyhemoglobin (CO-Hb) levels as a biomarker to predict the development and severity of bronchopulmonary dysplasia (BPD). Methods. Twenty-five infants born at <33 wk of gestational age or with a birth weight of <1,500 g were enrolled. CO-Hb levels were measured between postnatal days 5 and 8, 12 and 15, 19 and 22, and 26 and 29. Urinary levels of 8-hydroxydeoxyguanosine (8-OHdG), advanced oxidation protein products, and Nε-(hexanoyl) lysine were measured between postnatal days 5 and 8 and 26 and 29. Receiver operating characteristic (ROC) analysis was used to compare the biomarkers’ predictive values. Results. Compared with infants in the no-or-mild BPD group, infants with moderate-to-severe BPD exhibited higher CO-Hb levels during the early postnatal period and higher 8-OHdG levels between postnatal days 5 and 8. Using ROC analysis to predict the development of moderate-to-severe BPD, the area under the curve (AUC) for CO-Hb levels between postnatal days 5 and 8 was higher than AUCs for the urinary markers. Conclusions. CO-Hb levels during the early postnatal period may serve as a practical marker for evaluating oxidative stress and the severity of subsequently developing BPD

Postnatal Changes in Humerus Cortical Bone Thickness Reflect the Development of Metabolic Bone Disease in Preterm Infants

Objective. To use cortical bone thickness (CBT) of the humerus to identify risk factors for the development of metabolic bone disease in preterm infants. Methods. Twenty-seven infants born at <32 weeks of gestational age, with a birth weight of <1,500 g, were enrolled. Humeral CBT was measured from chest radiographs at birth and at 27-28, 31-32, and 36–44 weeks of postmenstrual age (PMA). The risk factors for the development of osteomalacia were statistically analyzed. Results. The humeral CBT at 36–44 weeks of PMA was positively correlated with gestational age and birth weight and negatively correlated with the duration of mechanical ventilation. CBT increased with PMA, except in six very early preterm infants in whom it decreased. Based on logistic regression analysis, gestational age and duration of mechanical ventilation were identified as risk factors for cortical bone thinning. Conclusions. Humeral CBT may serve as a radiologic marker of metabolic bone disease at 36–44 weeks of PMA in preterm infants. Cortical bones of extremely preterm infants are fragile, even when age is corrected for term, and require extreme care to lower the risk of fractures