Lipopolysaccharide induces proinflammatory cytokines and chemokines in experimental otitis media through the prostaglandin D2 receptor (DP)-dependent pathway

Abstract

SummaryOtitis media is one of the most common and intractable ear diseases, and is the major cause of hearing loss, especially in children. Multiple factors affect the onset or development of otitis media. Prostaglandin D2 is the major prostanoid involved in infection and allergy. However, the role of prostaglandin D2 and prostaglandin D2 receptors on the pathogenesis of otitis media remains to be determined. Recent studies show that D prostanoid receptor (DP) and chemoattractant receptor-homologous molecule expressed on T helper type 2 (Th2) cells (CRTH2) are major prostaglandin D2 receptors. In this study, homozygous DP single gene-deficient (DP CRTH2-/-mice display inflammatory reactions similar to wild-type mice. These findings indicate that prostaglandin D2 may play significant roles in LPS-induced experimental otitis media via DP.

Sensitivity of spiral ganglion neurons to damage caused by mobile phone electromagnetic radiation will increase in lipopolysaccharide-induced inflammation in vitro model

“…Some researchers have successfully set up the animal model of otitis media [ 33 ], but the inner ear is located deep in the temporal bone; the progress of inflammation and related indicators are difficult to observe; therefore, in this study, we choice an in vitro model to explore the biological effect of electromagnetic radiation, but we will try to investigate the possible cooperative effects of RF-EMR and LPS on any biological alterations in an in vivo model in further research.…”

Elevated levels of circulating CD4+CRTh2+ T cells characterize severe asthma

“…CRTh2 is considered a marker of human Th2 cells, within the CD4 + T cell subset , but is also expressed by eosinophils, basophils and group 2 innate lymphoid cells (ILC2) . Although a major source of PGD 2 is mast cells following allergen cross‐linking of IgE , it is also produced by other inflammatory cells activated by bacterial and viral products. In vitro, PGD 2 ‐CRTh2 activation mediates production of IL‐4, IL‐5, and IL‐13 from both Th2 cells and ILC2 , and so these mediators are now referred to as type 2 cytokines.…”

Otitis Media: State of the art concepts and treatment

“…Stol et al [74] underlined the early effect on cytokine production in middle ear homogenates as IL-1β and TNF-α were induced at 48 and 96 h after nasopharyngeal infection by SP but not at 144 h. Endotoxins from Salmonella Typhimurium or LPS were used to induce OM in three studies by transtympanic inoculation [101][102][103]. All the cytokines cited before were also upregulated in these experiments, assaying the protein concentration in MEEs or middle ear washes.…”

“…Therefore, when patients fail to improve while receiving amoxicillin, neither trimethoprimsulfamethoxazole [103] nor erythromycin/sulfisoxazole is appropriate therapy.…”