Chondrocyte dedifferentiation has been noted in osteoarthritic cartilage, but the contribution of this phenomenon is poorly understood. Interleukin (IL)-1beta, the major pro-inflammatory cytokine found in osteoarthritic synovial fluid, induces the dedifferentiation of cultured articular chondrocytes, whereas E-series prostaglandins (PGE) are capable of inducing cell differentiation. Since PGE(2...

We tested the hypothesis that interleukin (IL)-1beta-induced cortisol synthesis stimulates alveolar fluid clearance in preterm fetuses. IL-1beta was administered subcutaneously daily to timed-pregnant guinea pigs for 3 days with and without simultaneous cortisol synthesis inhibition by metyrapone. Fetuses were obtained by abdominal hysterotomy at 61 and 68 days gestation and instilled with isos...

Interleukin (IL)-1beta is produced primarily by activated mononuclear phagocytic cells in the lung airway and functions as a potent proinflammatory cytokine. Release of IL-1beta in the airway microenvironment induces the production of proinflammatory factors from parenchymal airway cells, including IL-8. To study the regulation of lung epithelial cell responsiveness to IL-1beta, the human type ...

OBJECTIVE Interleukin-8 (IL-8) is a soluble human-specific chemokine implicated in the development of the chronic inflammatory disease atherosclerosis. Recently, we showed that atheroprone hemodynamics induced IL-8 secretion from endothelial cells (ECs) concurrent with increased EC/smooth muscle cell (SMC) VCAM-1 expression in a human hemodynamic coculture model. Despite an IL-8 association wit...

BACKGROUND Small intestinal epithelial cells (SIEC) may contribute to local immune regulation. AIM To examine production of interleukin (IL)-1alpha, IL-1beta and IL-6 by freshly isolated human SIEC. METHODS IL-1alpha and IL-1beta mRNA in epithelial layers (EL) prepared from small intestine and in intestinal epithelial cell (EC) lines were examined by reverse transcription-polymerase chain r...

Different degrees of beta-cell failure and apoptosis are present in type 1 and type 2 diabetes. It has been recently suggested that high glucose-induced beta-cell apoptosis in type 2 diabetes shares a final common pathway with type 1 diabetes, involving interleukin-1beta (IL-1beta) production by beta-cells, nuclear factor-kappaB (NF-kappaB) activation, and death via Fas-FasL. The aim of this st...

Peripheral administration of bacterial endotoxin, an immune stimulant, induces evidence of activation in vagal primary afferent neurons. To determine whether interleukin-1beta (IL-1beta) is part of the molecular pathway leading to this activation, we assessed the expression of the neuronal activation marker c-Fos in vagal primary afferent neurons after intraperitoneal injections of IL-1beta (2 ...

Proinflammatory cytokines are elevated in disorders characterized by muscle wasting and weakness, such as inflammatory myopathies and AIDS wasting. We recently demonstrated that TNF-alpha impairs the ability of insulin-like growth factor (IGF)-I to promote protein synthesis in muscle precursor cells. In this study we extend these findings by showing that low concentrations of IL-1beta impair IG...

Actinobacillus actinomycetemcomitans produces a leukotoxin that selectively kills human leukocytes. Recently, we reported that macrophages are highly sensitive to leukotoxin and that their lysis involves activation of caspase 1. In this study, we show that leukotoxin also induces the production and release of proinflammatory cytokines from human macrophages. The macrophages were challenged with...