Potential differences in somatosensory function during premenopause and early and late postmenopause in patients with burning mouth syndrome: An observational case–control study

Background/purpose: Burning mouth syndrome (BMS) is a chronic condition presenting as intraoral burning or dysesthesia, with a high preponderance in menopausal women. This study aimed to examine the association between somatosensory dysfunction and BMS in premenopausal, early postmenopausal, and late postmenopausal patients, using a standardized Quantitative Sensory Testing (QST) protocol, and to determine the predictive value of thermal or mechanical perception by QST for detecting BMS. Materials and methods: An observational case–control study was performed with 36 female participants with BMS (12 premenopausal, 10 early postmenopausal, and 14 late postmenopausal) and 42 age- and sex-matched healthy volunteers (21 premenopausal, 10 early postmenopausal, and 11 late postmenopausal). Neurophysiological tests were used to evaluate somatosensory dysfunction at the tongue. Results: Z-score in the late postmenopausal BMS group revealed a gain of function for the cold pain threshold and heat pain threshold (Z = 2.08 and 3.38, respectively). In the multiple regression analysis with the Visual Analog Scale as the dependent variable, the vibration detection threshold predicted the severity of burning mouth sensation in the premenopausal group. Conclusion: Late postmenopausal patients with BMS showed an increased response of the tongue to noxious thermal stimuli. This supports the theory that changes in sex hormones may affect trigeminal somatosensory function, particularly during the late postmenopausal stage in patients with BMS

Corrected and Republished from: The COP9 Signalosome Interacts with and Regulates Interferon Regulatory Factor 5 Protein Stability.

© 2018 American Society for Microbiology. The transcription factor interferon regulatory factor 5 (IRF5) exerts crucial functions in the regulation of host immunity against extracellular pathogens, DNA damage-induced apoptosis, death receptor signaling, and macrophage polarization. Tight regulation of IRF5 is thus warranted for an efficient response to extracellular stressors and for limiting autoimmune and inflammatory responses. Here we report that the COP9 signalosome (CSN), a general modulator of diverse cellular and developmental processes, associates constitutively with IRF5 and promotes its protein stability. The constitutive CSN/IRF5 interaction was identified using proteomics and confirmed by endogenous immunoprecipitations. The CSN/IRF5 interaction occurred on the carboxyl and amino termini of IRF5; a single internal deletion (Δ455-466) was found to significantly reduce IRF5 protein stability. CSN3 was identified as a direct interacting partner of IRF5, and knockdown of this subunit with small interfering RNAs (siRNAs) resulted in enhanced degradation. Degradation was further augmented by knockdown of CSN1 and CSN3 together. The ubiquitin E1 inhibitor UBEI-41 or the proteasome inhibitor MG132 prevented IRF5 degradation, supporting that its stability is regulated by the ubiquitin-proteasome system. Importantly, activation of IRF5 by the death receptor ligand tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) resulted in enhanced degradation via loss of the CSN/IRF5 interaction. This study defines the CSN as a new interacting partner of IRF5 that controls its stability

Assessment of a New Diagnostic Tool in the Diagnosis of Temporomandibular Disorders

Many dentists receive little to no training in the diagnosis of temporomandibular disorders (TMD), despite the high prevalence of patients with these conditions. Currently, there exists a decision tree diagnostic tool to guide clinicians through the Diagnostic Criteria for Temporomandibular Disorders; however, there is a need for a more accessible and user friendly diagnostic tool. We designed a new, checklist-style diagnostic tool with these goals in mind, and in this study, we compared the use of our new tool with the use of the pre-existing decision tree tool

TRIpartite Motif 21 (TRIM21) Differentially Regulates the Stability of Interferon Regulatory Factor 5 (IRF5) Isoforms

<div><p>IRF5 is a member of the Interferon Regulatory Factor (IRF) family of transcription factors activated downstream of the Toll-Like receptors (TLRs). Polymorphisms in <i>IRF5</i> have been shown to be associated with the autoimmune disease Systemic Lupus Erythematosus (SLE) and other autoimmune conditions, suggesting a central role for IRF5 in the regulation of the immune response. Four different IRF5 isoforms originate due to alternative splicing and to the presence or absence of a 30 nucleotide insertion in <i>IRF5</i> exon 6. Since the polymorphic region disturbs a PEST domain, a region associated with protein degradation, we hypothesized that the isoforms bearing the insertion might have increased stability, thus explaining the association of individual IRF5 isoforms with SLE. As the E3 ubiquitin ligase TRIpartite Motif 21 (TRIM21) has been shown to regulate the stability and hence activity of members of the IRF family, we investigated whether IRF5 is subjected to regulation by TRIM21 and whether dysregulation of this mechanism could explain the association of IRF5 with SLE. Our results show that IRF5 is degraded following TLR7 activation and that TRIM21 is involved in this process. Comparison of the individual IRF5 variants demonstrates that isoforms generated by alternative splicing are resistant to TRIM21-mediated degradation following TLR7 stimulation, thus providing a functional link between isoforms expression and stability/activity which contributes to explain the association of IRF5 with SLE.</p></div

Genetic variation in catechol-O-methyltransferase is associated with individual differences in conditioned pain modulation in healthy subjects

Background: Genetic variation in the catechol-O-methyltransferase (COMT) gene is associated with sensitivity to both acute experimental pain and chronic pain conditions. Four single nucleotide polymorphisms (SNPs) have traditionally been used to infer three common haplotypes designated as low, average and high pain sensitivity and are reported to affect both COMT enzymatic activity and pain sensitivity. One mechanism that may partly explain individual differences in sensitivity to pain is conditioned pain modulation (CPM). We hypothesized that variation in CPM may have a genetic basis. Methods: We evaluated CPM in 77 healthy pain-free Caucasian subjects by applying repeated mechanical stimuli to the dominant forearm using 26-g von Frey filament as the test stimulus with immersion of the non-dominant hand in hot water as the conditioning stimulus. We assayed COMT SNP genotypes by the TaqMan method using DNA extracted from saliva. Results: SNP rs4680 (val158met) was not associated with individual differences in CPM. However, CPM was associated with COMT low pain sensitivity haplotypes under an additive model (p = 0.004) and the effect was independent of gender. Conclusions: We show that, although four SNPs are used to infer COMT haplotypes, the low pain sensitivity haplotype is determined by SNP rs6269 (located in the 5′ regulatory region of COMT), suggesting that inherited variation in gene expression may underlie individual differences in pain modulation. Analysis of 13 global populations revealed that the COMT low pain sensitivity haplotype varies in frequency from 13% to 44% and showed that two SNPs are sufficient to distinguish all COMT haplotypes in most populations

TRIM21 ubiquitinates IRF5 and interacts with IRF5 isoforms upon TLR7 stimulation.

<p>A, Myc-tagged IRF5 isoforms and HA-Ubiquitin were overexpressed in HEK-293T in presence or absence of Xpress-TRIM21. Lysates were incubated with HA agarose and the extent of IRF5 ubiquitination was assessed by anti-Myc immunoblot (top panel). Expression of IRF5 and TRIM21 in the Whole Cell Lysate (WCL) is shown in the bottom panels. I (lane 11), Myc-IRF5-V1 Input; B (lane 12), HA-agarose beads alone; H.C., Heavy Chain. B, Top panel: THP-1 were stimulated with Imiquimod (10 µg/ml) for 4 and 8 hours and lysates were incubated with GST-PRY/SPRY TRIM21 (lanes 1–3) or GST alone (lane 4) bound to glutathione agarose. Interaction of IRF5 and total IRF5 expression in the whole cell lysate (WCL) was assessed by immunoblot. Bottom panel: PBMCs were treated with 10 µg/ml Imiquimod for the indicated times. Proteins were resolved by SDS PAGE and immunoblotting performed with anti-IRF5 and anti-β-Actin antibodies. C, Myc-IRF5 isoforms and Xpress-TRIM21 were overexpressed in HEK-TLR7 cells. Following 8 hours treatment with CL097 (5 µg/ml) Xpress-TRIM21 was immunoprecipitated from cell lysates and association of TRIM21 with IRF5 isoforms was assessed by anti-Myc immunoblot. Normal mouse IgG (lanes 9 and 10) was used as negative control. WCL, whole cell lysate; H.C., Heavy Chain.</p

Analysis of interaction domains of IRF5 and TRIM21.

<p>A, Exon schematic of IRF5 isoforms structure. DBD, DNA binding domain; PEST, region rich in proline (P), glutamic acid (E), serine (S) and threonine (T) residues; IAD, IRF association domain; SRR, Serine-Rich Region. Dotted lines represent deleted regions. The dark grey box in exon 6 represents the polymorphic 30 nucleotide insertion while *indicates the position of the alternative splicing site 48 nucleotides from exon 6 5′ end. B, Domain structure of TRIM21 (top) and GST-tagged PRY/SPRY domain (bottom). C, Myc-IRF5 isoforms were overexpressed in HEK-293T and lysates were incubated with GST-PRY/SPRY TRIM21 (left panel) or GST alone (right panel) bound to glutathione agarose. Interaction of IRF5 isoforms was assessed by immunoblot (top panels) and total IRF5 expression in the whole cell lysate (WCL) is shown in the bottom panel. D, Schematic diagram of exons encoding full length IRF5-V3 (top) and exons deletions originating C-terminal (C1) or N-terminal (N1–N4) truncated proteins. E, Full length FLAG-IRF5 or deletion mutants were overexpressed in HEK-293T and lysates were incubated with GST-PRY/SPRY TRIM21 (top panel) or GST alone bound to glutathione agarose. Interaction of IRF5 was assessed by anti-FLAG immunoblot and total IRF5 expression in the whole cell lysate (WCL) is shown. Anti-GST immunoblots (bottom panels) show amount of GST-PRY/SPRY TRIM21 or GST incubated with cell lysates. *indicates non-specific signal. Band intensity was calculated and ratio between pulled-down signal and total expression in the whole cell lysate is shown (bottom graph).</p

TRIM21 interacts with IRF5 and regulates its stability and activity.

<p>A, Myc-IRF5 and Xpress-TRIM21 were overexpressed in HEK-293T cells. 24 hours post-transfection cells were lysed, Xpress-TRIM21 was immunoprecipitated from cell lysates and association of TRIM21 with IRF5 was assessed by anti-Myc immunoblot. WCL, whole cell lysate; H.C., Heavy Chain; *indicates non-specific signal. B, HEK-293T cells were transfected with 2 µg of plasmids encoding shRNA targeting TRIM21 or scrambled shRNA as a negative control. 48 hours after transfection cells were lysed and levels of IRF5, TRIM21 and α-actinin were determined by western blot. Bottom graphs show densitometric analysis of relative IRF5 levels (left) and expression of IL-6 as determined by RT-PCR of RNA extracted from the same samples (right). C, HEK293T were transfected with plasmids encoding the luciferase reporter gene under the control of the IFNA4 promoter and Myc-tagged IRF5 in presence of increasing amounts of Xpress-TRIM21. The TK-Renilla plasmid was used as internal control. Luciferase activity was measured 48 hours after transfection and normalized to renilla activity. Results are shown as fold activation over Empty Vector control. Expression of IRF5, TRIM21 and α-actinin was determined by western blot with anti-Myc, anti-Xpress and anti-α-actinin, respectively. *<i>p</i><0.05 as determined by Student’s <i>t</i>-test.</p