BACKGROUND AND OBJECTIVES: Osteoclasts are the principal cell of bone resorption playing a major role in focal bone erosion associated with cholesteatoma. This study was conducted in order to investigate direct effect of substance P (SP) on osteoclastogenesis and osteoclastic bone resorption in vitro. MATERIALS AND METHOD: SP dose response was measured in receptor activator for NF-kappaB ligand (RANKL)-induced mouse osteoclast culture and osteoclastic bone resorption assay. RT-PCR was performed for the expression of neurokinin(NK) receptor mRNAs in osteoclasts. RESULTS: Treatment with SP (100 nM and 1000 nM) significantly increased osteoclastogenesis. SP (0.1 nM and 1 nM) significantly increased resorption surface area on dentin slices by osteoclasts. Cultured osteoclasts expressed NK-2 receptor mRNA. CONCLUSION: SP has a direct upregulatory effect on osteoclastogenesis and osteoclastic bone resorption that is mediated possibly by NK-2 receptor.
Animals ; Bone Resorption* ; Cholesteatoma ; Dentin ; Mice ; NF-kappa B ; Osteoclasts* ; Receptors, Neurokinin-2 ; RNA, Messenger ; Substance P*

ObjectiveTo investigate the expressions of substance P (SP) and neurokinin-1 receptor (NK-1R) in the posterior horn of the L5－S2 spinal cord in the rat model of chronic nonbacterial prostatitis (CNP) at different time points of modeling.

METHODSForty adult male SD rats were randomly divided into four groups of equal number, control, 45 d model, 60 d model, and 90 d model, and proteins were obtained from the prostatic tissue of another 30 rats. The CNP model was made by intraperitoneal injection of 0.5 ml DPT vaccineand intradermal injection of mixed solution of 1 ml prostatein extract and complete adjuvant at a 1∶1 ratio, while the control rats were injected with the same volume of normal saline. At 45, 60, and 90 days after modeling, we measured the paw withdrawal threshold (PWT) of the rats, determined the levels of TNF-α, IL-1β, IL-2, and IL-10 in the prostate tissue by ELISA, observed the histomorphological changes in the prostate by transmission electron and light microscopy, and detected the expressions of SP and NK1-R in the L5－S2 spinal cord by immunohistochemistry.

RESULTSThe model rats showed significantly increased sensitivity to pain, with remarkably lowered PWT at 45, 60, and 90 days after modeling. The levels of TNF-α, IL-1β, IL-2, and IL-10 in the prostate tissue were markedly elevated in the CNP models as compared with those in the controls (all P<0.05), most significantly at 90 days (all P<0.05). Immunohistochemistry showed that the expressions of SP and NK-1R were remarkably higher in the CNP model groups than in the control (all P<0.05), the highest at 90 days. Light microscopy revealed no inflammatory cell infiltration in the prostate tissue of the control rats, and obvious edema and increased lymphocytes were observed with the prolonged time of modeling.Transmission electron microscopy showed inflammatory changes in the prostate tissue of the model rats and that peritubular interstitial edema was most obvious at 90 days, with widened intervals between peritubular cells and the epithelial base and increased numbers of fibroblasts and collagen fibrils.

CONCLUSIONSThe synthesis of SP and the level of NK-1R were increased in the posterior horn of the L5－S2 spinal cord in the rat model of CNP.

Animals ; Interleukin-10 ; metabolism ; Interleukin-1beta ; metabolism ; Interleukin-2 ; metabolism ; Male ; Pain ; Prostatitis ; metabolism ; physiopathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Neurokinin-1 ; metabolism ; Spinal Cord ; metabolism ; Substance P ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

Three diisocyanates can cause occupational asthma (OA): toluene diisocyanate (TDI), 4,4 diphenylmethane diisocyanate (MDI), and 1,6-hexamethylene diisocyanate (HDI). We analyzed potential biomarkers of isocyanate-induced OA, based on investigated immunologic, genetic, neurogenic, and protein markers, because there is no serological testing method. The prevalence of serum IgG to cytokeratin (CK)18 and CK19 in TDI-OA was significantly higher than in controls, although the prevalence of these antibodies was too low for them to be used as biomarkers. Another candidate biomarker was serum IgG to tissue transglutaminase (tTG), because the prevalence of serum specific IgG to tTG was significantly higher in patients with TDI-OA than in controls. The human leukocyte antigen (HLA) DRB1*1501-DQB1*0602-DPB1*0501 haplotype may be used as a genetic marker for TDI-OA in Koreans via enhanced specific IgE sensitization in exposed subjects. The genetic polymorphisms of catenin alpha 3, alpha-T catenin (CTNNA3) were significantly associated with TDI-OA. Additionally, examining the neurokinin 2 receptor (NK2R) 7853G>A and 11424 G>A polymorphisms, the NK2R 7853GG genotype had higher serum vascular endothelial growth factor (VEGF) levels than the GA or AA genotypes among Korean workers exposed to TDI. To identify new serologic markers using a proteomic approach, differentially expressed proteins between subjects with MDI-OA and asymptomatic exposed controls in a Korean population showed that the optimal serum cutoff levels were 69.8 ng/mL for ferritin and 2.5 microg/mL for transferrin. When these two parameters were combined, the sensitivity was 71.4% and the specificity was 85.7%. The serum cytokine matrix metalloproteinase-9 (MMP-9) level is a useful biomarker for identifying cases of TDI-OA among exposed workers. Despite these possible biomarkers, more effort should be focused on developing early diagnostic biomarkers using a comprehensive approach based on the pathogenic mechanisms of isocyanate-induced OA.
Antibodies ; Asthma ; Asthma, Occupational ; Biomarkers ; Cyanates ; Ferritins ; Genetic Markers ; Genotype ; GTP-Binding Proteins ; Haplotypes ; Humans ; Immunoglobulin E ; Immunoglobulin G ; Isocyanates ; Keratins ; Leukocytes ; Matrix Metalloproteinase 9 ; Polymorphism, Genetic ; Prevalence ; Proteins ; Receptors, Neurokinin-2 ; Serologic Tests ; Toluene 2,4-Diisocyanate ; Transferrin ; Transglutaminases ; Vascular Endothelial Growth Factor A