Squamous metaplasia and BCL-6 in pediatric adenoid accompanied by otitis media with effusion

PURPOSE: Deterioration of local immunity in the adenoids may make them vulnerable to infection by microorganisms, resulting in otitis media with effusion. To determine the factors associated with this condition, we evaluated adenoid size, mucosal barrier, squamous changes of ciliated epithelium, IgA secretion, and BCL-6 expression in adenoids. MATERIALS AND METHODS: Seventeen children diagnosed with otitis media with effusion (OME group) and 20 children without any history of OME (control group) were enrolled. Their adenoids were sized by lateral view X-ray and stained with hematoxylin and eosin to detect squamous metaplasia. The adenoids were also stained with cytokeratin to evaluate mucosal barriers, and with anti- IgA antibody and anti- BCL-6 antibody to determine expression of IgA and BCL-6. RESULTS: The OME group showed greater incidence of squamous metaplasia, fewer ciliated cells, and lower expression of BCL-6 (p < 0.05 each). Deterioration of the mucosal barrier was detected in the OME group (p > 0.05). IgA secretion and adenoid size were the same for the OME and the control groups. CONCLUSION: These results suggest that increased squamous metaplasia and lower BCL-6 expression in adenoids may be associated with increased susceptibility to OME.     

Differential effects of ceramide species on exocytosis in rat PC12 cells

Increases in several ceramide species have been shown by non-targeted lipid profiling (lipidomics) of the rat hippocampus after kainate lesions (Guan et al. FASEB J 20:1152–1161, 2006). This study was carried out to examine possible effects of ceramide species on exocytosis. Significant increase in membrane capacitance in voltage-clamped rat pheochromocytoma (PC12) cells, an indication of exocytosis, was detected immediately after external application of C2, C6, and C18 ceramide. In contrast, no increase in capacitance was found after addition of C16 and C20 ceramide, or DMSO vehicle. The effect of ceramide on exocytosis was dependent on the integrity of lipid rafts. Treatment of cells with the cholesterol binding agent/disruptor of lipid rafts, methyl β cyclodextrin, prior to addition of C18 ceramide suppressed the increase in capacitance induced by this lipid species. The ability of C2, C6 and C18 ceramide to trigger exocytosis was confirmed using total internal reflection fluorescence microscopy (TIRFM) experiments. External application of these species caused an exponential decrease in the number of subplasmalemmal neuropeptide Y (NPY)-enhanced green fluorescence protein (EGFP) labeled vesicles, indicating exocytosis. Interestingly, C18 is also the ceramide species that showed the greatest increase in the rat hippocampus after kainate excitotoxicity. It is postulated that C18 ceramide might facilitate exocytosis of glutamate from damaged neurons, thus propagating neuronal injury.     

Anti‐inflammatory effect of platelet‐rich plasma on nucleus pulposus cells with response of TNF‐α and IL‐1

The purpose of this study was to investigate the anti‐inflammatory effect of platelet‐rich plasma (PRP) with collagen matrix on human nucleus pulposus (NP) cell in response to pro‐inflammatory cytokines such as tumor necrosis factor‐alpha (TNF‐α) and interleukin‐1 (IL‐1). NP cells from human disks were cultured in a monolayer and maintained in the collagen matrix prior to the addition of recombinant human IL‐1 and TNF‐α. After applying IL‐1 and TNF‐α, PRP prepared by using a commercially available platelet concentration system was added. The response was investigated using real‐time PCR for mRNA expression of type II collagen, aggrecan, matrix metalloproteinase‐3 (MMP‐3), and cyclooxygenase‐2 (COX‐2). The combination of IL‐1β and TNF‐α led to decrease of matrix synthesis gene expression such as collagen type II and aggrecan and increase of the degradation gene expression of COX‐2 and MMP‐3, compared to the control. Consecutive PRP exposure significantly recovered the down‐regulated gene expression of collagen type II and aggrecan and significantly reduced the increased MMP‐3 and COX‐2 gene expression, compared to that of control groups with pro‐inflammatory cytokines. The administration of PRP with collagen matrix markedly suppressed cytokine‐induced pro‐inflammatory degrading enzymes and mediators in the NP cell. It also rescued gene expression concerning matrix synthesis, thereby stabilizing NP cell differentiation. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:551–556, 2014.