Clinical and ultrasound features of difficult-to-treat rheumatoid arthritis: A multicenter RA ultrasound cohort study.

OBJECTIVE: The optimal strategy for difficult-to-treat (D2T) rheumatoid arthritis (RA) has not been identified, and the ultrasound characteristics of D2T RA have not been reported. We investigated the clinical characteristics and factors contributing to the outcome in D2T RA in a multicentre RA ultrasound observational cohort. METHOD: We reviewed 307 Japanese patients diagnosed with RA who underwent treatment with biological and targeted synthetic disease-modifying anti-rheumatic drugs (b/tsDMARDs). We compared the differences in patient characteristics between the D2T RA and non-D2T RA groups. We examined the factors contributing to a good response [defined as b/tsDMARD continuation and Clinical Disease Activity Index (CDAI) ≤ 10 at 12 months] in the D2T RA patient group. RESULTS: Forty-three patients (14%) were categorized as D2T RA and the remaining 264 (86%) as non-D2T RA at baseline. The grey-scale (GS) score, disease duration, and CDAI at the initiation of treatment were significantly higher in the D2T RA group than in the non-D2T RA group. In contrast, the power Doppler (PD) score was not significantly different between the two groups. Of the 43 D2T RA patients, 20 achieved a good response. The introduction of CTLA4-Ig (n = 5) was significantly associated with a good response in analysis based on inverse probability weighting with propensity score. GS and PD scores at baseline were not significantly associated with therapeutic response at 12 months in D2T RA patients. CONCLUSIONS: Patients with D2T RA had high clinical and ultrasound activity and poor responses to treatment with b/tsDMARDs. CTLA4-Ig was associated with a good response at 12 months in D2T RA patients.

Ultrasound efficacy of targeted-synthetic disease-modifying anti-rheumatic drug treatment in rheumatoid arthritis: a multicenter prospective cohort study in Japan.

OBJECTIVE: This study investigated the effectiveness of treatment with Janus kinase (JAK) inhibitors in rheumatoid arthritis (RA) assessed by ultrasonography (US) activity, and the influence of patient characteristics and previous treatments. METHOD: This prospective study assessed 60 treatment initiations among 53 Japanese patients diagnosed with RA who underwent treatment with JAK inhibitors during June 2013 to February 2020. Of the 53 patients, seven patients were enrolled in duplicate because they were treated with two different JAK inhibitors at different periods. For each case, the improvement rate on the power Doppler (PD) score was assessed at 6 month follow-up. Median improvement rate of PD score was used to classify cases as either US responders or non-responders, and patient characteristics were compared between the two groups. RESULTS: All indicators of clinical disease activity and US activity showed a significant improvement at 3 months compared with baseline. Although the JAK inhibitor-cycler group and the interleukin-6 (IL-6) inhibitor inadequate response (IR) group tended to show a later improvement for US activity, all indicators of clinical disease activity and US activity showed a significant improvement at 6 months compared with baseline for both groups. Multivariate analysis showed that concomitant methotrexate use and an IR to the previous biologic or targeted-synthetic disease-modifying anti-rheumatic drug (b/tsDMARD) treatment were independently and significantly associated with US responders. CONCLUSION: Use of a JAK inhibitor in combination with methotrexate and an absence of IR to any previous b/tsDMARDs demonstrated superior effectiveness for patients with RA.

Discrepancy between clinical and ultrasound remissions in rheumatoid arthritis: a multicentre ultrasound cohort study in Japan.

Objectives: Using multicentre ultrasound (US) cohort data among patients with rheumatoid arthritis (RA), we aimed to identify baseline factors that permit differentiation between two patient cohorts achieving US remission and clinical remission, and to determine the factors contributing to the discrepancy.Method: We reviewed 248 Japanese patients diagnosed with RA who underwent treatment with biological disease-modifying anti-rheumatic drugs at 13 centres. We performed US assessments of the synovia of 22 joints. We assessed the percentages of patients with clinical remission and US remission, defined as total power Doppler scores of 0 at 12 months.Results: The 87 patients who achieved US remission were divided into a group that achieved both clinical and US remission (n = 53) and a group that achieved US remission only (n = 34). Baseline factors that were significantly and independently associated with clinical remission at 12 months among patients who also achieved US remission included short disease duration, the presence of concomitant methotrexate use, and low patient global assessment score (p < 0.05, p < 0.05, and p < 0.005, respectively).Conclusions: RA patients with baseline high patient global assessment scores and long disease duration at baseline were unlikely to achieve clinical remission even after achieving US remission. Objective joint assessments using US provide additional information of potential importance for the management of RA.

In the absence of a basal lamina, ameloblasts absorb enamel in a serumless and chemically defined organ culture system.

OBJECTIVES: Tooth organ development was examined in a serumless, chemically defined organ culture system to determine whether morphological and functional development was identical to that in in vivo and serum-supplemented organ cultures. METHODS: Mouse mandibular first molar tooth organs at 16 days of gestation were cultured for up to 28 days in a Tronwell culture system using a serum-supplemented or serumless, chemically defined medium. After culture, specimens were processed for assessing tooth development using ultrastructural, immunohistochemical, and mRNA expression analyses. RESULTS: In serum-supplemented conditions, inner enamel epithelial cells differentiated into secretory-stage ameloblasts, which formed enamel and reached the maturation stage after 14 and 21 days of culture, respectively. Ameloblasts deposited a basal lamina on immature enamel. Conversely, in serumless conditions, ameloblasts formed enamel on mineralized dentin after 21 days. Moreover, maturation-stage ameloblasts did not form basal lamina and directly absorbed mineralized enamel after 28 days of culture. RT-PCR analysis indicated that tooth organs, cultured in serumless conditions for 28 days, had significantly reduced expression levels of ODAM, amelotin, and laminin-322. CONCLUSIONS: These results indicate that several differences were detected compared to the development in serum-supplemented conditions, such as delayed enamel and dentin formation and the failure of maturation-stage ameloblasts to form basal laminae. Therefore, our results suggest that some factors might be required for the steady formation of mineralized dentin, enamel, and a basal lamina. Additionally, our results indicate that a basal lamina is necessary for enamel maturation.

Significance of anti-Ro/SSA antibodies in the response and retention of abatacept in patients with rheumatoid arthritis: a multicentre cohort study.

Objective: To determine whether the positivity of baseline anti-Ro/Sjögren's syndrome antigen A (SSA) antibodies influences the response to abatacept, we compared therapeutic responses between anti-Ro/SSA antibody-negative and -positive patients with rheumatoid arthritis (RA) using a multicentre RA ultrasonography prospective cohort. Method: We reviewed Japanese patients with RA who started abatacept as the first biological disease-modifying anti-rheumatic drug between June 2013 and April 2018. We assessed 28-joint Disease Activity Score-erythrocyte sedimentation rate (DAS28-ESR) change between baseline and 6 or 12 months after treatment in RA patients treated with abatacept, and European League Against Rheumatism (EULAR) response at 6 and 12 months. The Global OMERACT-EULAR Synovitis Score (GLOESS) was calculated at baseline and at 6 and 12 months. Results: Overall, 51 patients were enrolled and divided into anti-Ro/SSA antibody-negative and -positive groups of 35 and 16, respectively. Median age at baseline was significantly higher in the anti-Ro/SSA antibody-negative group (p = 0.04). The retention rate and percentage of EULAR good responders at 12 months were significantly higher in the anti-Ro/SSA antibody-negative group (both p = 0.02). Anti-Ro/SSA antibody-negative patients exhibited larger decreases in both DAS28-ESR and DAS28-C-reactive protein at 12 months than anti-Ro/SSA antibody-positive patients (p = 0.02 and 0.04, respectively). GLOESS decreased significantly at 6 months in anti-Ro/SSA antibody-negative patients (p = 0.03). Multivariate analyses showed that anti-Ro/SSA antibody positivity was an independent factor associated with change in the DAS28-ESR at 6 months (p < 0.05). Conclusion: Anti-Ro/SSA antibody positivity predicts a poor response to abatacept and low retention rate.

IL-15 is a biomarker involved in the development of rapidly progressive interstitial lung disease complicated with polymyositis/dermatomyositis.

BACKGROUND: Polymyositis/dermatomyositis (PM/DM) is an autoimmune disease that is sometimes complicated with rapidly progressive interstitial lung disease (RPILD). However, serum and lung biomarkers that can predict RPILD development remain unclear. OBJECTIVES: To determine potential serum and lung biomarkers that can predict RPILD development in patients with PM/DM-ILD. METHODS: In total, 49 patients with PM/DM-ILD were enrolled. We measured the serum levels of 41 cytokines/chemokines, ferritin and anti-MDA5 antibody, compared them between the RPILD (n = 23) and non-RPILD (n = 26) groups, and ranked them by their importance through random forest analysis. To distinguish the two groups, we determined biomarker combinations by logistic regression analysis. We also measured the bronchoalveolar lavage fluid (BALF) levels of 41 cytokines/chemokines. Using immunohistochemistry, we examined IL-15 expression in lung tissues. The IL-15 production was also investigated using A549 and BEAS-2B cells. RESULTS: The RPILD group had significantly higher IL-15, IL-1RA, IL-6, CXCL10, VCAM-1, anti-MDA5 antibody and ferritin serum levels than the non-RPILD group, but it had a significantly low CCL22 level. Meanwhile, anti-MDA5 antibody, IL-15, CXCL8, CCL22, IL-1RA and ferritin were the best combination to distinguish the two groups. IL-15 and CCL22 were also predictive marker for RPILD development in anti-MDA5 antibody-positive patients. Additionally, the RPILD group had significantly high IL-15 levels in BALF. The lung tissues expressed IL-15, which increased after cytokine stimulation in the A549 cells. CONCLUSION: This study identified a combination of biomarkers predicting PM/DM-RPILD progression, and IL-15 is an important cytokine for predicting RPILD development and reflecting ILD severity.

Anti-citrullinated protein antibody titre as a predictor of abatacept treatment persistence in patients with rheumatoid arthritis: a prospective cohort study in Japan.

Objective: Successful rheumatoid arthritis (RA) outcome depends on treatment efficacy in the early stages of the disease and its sustainability. It is thus critical to identify factors predicting treatment persistence with biological agents, such as abatacept. We compared clinical profiles, including early changes in autoantibody titres at 3 months, between patients with RA demonstrating sustained persistence and those discontinuing abatacept treatment.Method: We prospectively enrolled 71 and 78 active RA patients treated with abatacept and tumour necrosis factor inhibitors (TNF-Is), respectively, who had previous disease-modifying anti-rheumatic drug) failure. Clinical characteristics were compared between non-continuation and continuation groups stratified according to abatacept or TNF-I persistence for at least 12 months from treatment initiation.Results: Significantly larger decreases in rheumatoid factor titre and anti-citrullinated protein autoantibody (ACPA) titre were observed in the continuation group of abatacept therapy at 3 months, and early reduction in ACPA titre remained a significant and independent predictor of sustained persistence with abatacept in multivariate analysis. In addition, we obtained the area under the receiver operator characteristics curve of 0.904 from a model including baseline ACPA titre and reduction of ACPA titre at 3 months. Sustained reduction of RA disease activity score at 12 months was significantly and independently associated with reduced ACPA titre at 3 months.Conclusions: Persistence with abatacept and sustained therapeutic response are associated with an early reduction in ACPA titre. Prediction of abatacept continuation and efficacy will facilitate the optimal design of therapy in the early stages of RA.

Factors predictive of long-term mortality in lupus nephritis: a multicenter retrospective study of a Japanese cohort.

BACKGROUND: Lupus nephritis (LN) is a major determinant of mortality in systemic lupus erythematosus (SLE). Here we evaluated the association between complete renal response (CR) and mortality in LN. METHODS: We retrospectively analyzed the cases of 172 of 201 patients with LN for whom data on the therapeutic response at 6 and 12 months after induction therapy were available. The patients underwent a renal biopsy at Nagasaki University Hospital and community hospitals in Nagasaki between the years 1990 and 2016. We determined the CR rates at 6 and 12 months after induction therapy initiation and evaluated the predictive factors for CR and their relationship with mortality. We performed univariate and multivariable competing risks regression analyses to determine the factors predictive of CR. The patients' survival data were analyzed by the Kaplan-Meier method with a log-rank test. RESULTS: The median follow-up duration after renal biopsy was 120 months (interquartile range: 60.3-191.8 months). The 5-, 10-, 15- and 20-year survival rates of our cohort were 99.3, 94.6, 92.0 and 85.4%, respectively. During follow-up, nine patients (5.2%) died from cardiovascular events, infection, malignancy and other causes. The multivariate analysis revealed that the following factors were predictive of CR. At 6 months: male gender (odds ratio (OR) 0.23, 95% confidence interval (CI) 0.08-0.65, p = 0.0028), proteinuria (g/gCr) (OR 0.83, 95% CI 0.71-0.97, p = 0.0098) and index of activity (0-24) (OR 0.84, 95% CI 0.71-0.99, p = 0.0382). At 12 months: male gender (OR 0.25, 95% CI 0.09-0.67, p = 0.0043) and index of activity (0-24) (OR 0.82, 95% CI 0.69-0.98, p = 0.0236). The Kaplan-Meier analysis showed that compared to not achieving CR at 12 months, achieving CR at 12 months was significantly correlated with the survival rate (OR 0.18, 95% CI 0.04-0.92, p = 0.0339). CONCLUSIONS: Our results suggest that the survival rate of patients with LN is associated with the achievement of CR at 12 months after induction therapy, and that male gender and a higher index of activity (0-24) are the common predictive factors for failure to achieve CR at 6 and 12 months.

The efficacy of adjunct tacrolimus treatment in pregnancy outcomes in patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) involves multiple organ systems and primarily affects women during their reproductive years. Pregnancy in a woman with SLE may lead to higher rates of disease flares. Little is known regarding which medications are safe to maintain remission and/or treat flares throughout such pregnancies. Here we retrospectively analyzed the efficacy of tacrolimus (TAC) in the pregnancy outcomes of SLE patients. We studied the 54 deliveries of 40 SLE patients over an eight-year period from 2008 to 2016. We used analyses of covariance with adjustments for the propensity score and inverse probability of treatment weights to compare the patient backgrounds between the TAC users and non-TAC users. TAC was administered to the patient in 15 of the 54 (27.8%) pregnancies, and these patients had a significantly higher dose of prednisolone, hypocomplementemia, lower estimated glomerular filtration rate, past history of lupus nephritis, and complication with antiphospholipid syndrome. In the adjusted background of the TAC deliveries, the risks of decreased fetal body weight, low birth weight infant, non-reassuring fetal status (NRFS), and preterm birth were not increased compared to the non-TAC deliveries. Thrombocytopenia and hypertension during the pregnancy were extracted as independent predictive risk factors for decreased fetal body weight and NRFS, respectively. We had anticipated that the maternal and fetal outcomes in the TAC-use deliveries would be poor before the analysis; however, the TAC-use group showed no significant difference in risks contributing to outcomes compared to the non-TAC group, suggesting that adjunct TAC treatment corrected various risk factors during the lupus pregnancies.

Randomized phase III study of bevacizumab plus FOLFIRI and bevacizumab plus mFOLFOX6 as first-line treatment for patients with metastatic colorectal cancer (WJOG4407G).

BACKGROUND: FOLFIRI and FOLFOX have shown equivalent efficacy for metastatic colorectal cancer (mCRC), but their comparative effectiveness is unknown when combined with bevacizumab. PATIENTS AND METHODS: WJOG4407G was a randomized, open-label, phase III trial conducted in Japan. Patients with previously untreated mCRC were randomized 1:1 to receive either FOLFIRI plus bevacizumab (FOLFIRI + Bev) or mFOLFOX6 plus bevacizumab (mFOLFOX6 + Bev), stratified by institution, adjuvant chemotherapy, and liver-limited disease. The primary end point was non-inferiority of FOLFIRI + Bev to mFOLFOX6 + Bev in progression-free survival (PFS), with an expected hazard ratio (HR) of 0.9 and non-inferiority margin of 1.25 (power 0.85, one-sided α-error 0.025). The secondary end points were response rate (RR), overall survival (OS), safety, and quality of life (QoL) during 18 months. This trial is registered to the University Hospital Medical Information Network, number UMIN000001396. RESULTS: Among 402 patients enrolled from September 2008 to January 2012, 395 patients were eligible for efficacy analysis. The median PFS for FOLFIRI + Bev (n = 197) and mFOLFOX6 + Bev (n = 198) were 12.1 and 10.7 months, respectively [HR, 0.905; 95% confidence interval (CI) 0.723-1.133; P = 0.003 for non-inferiority]. The median OS for FOLFIRI + Bev and mFOLFOX6 + Bev were 31.4 and 30.1 months, respectively (HR, 0.990; 95% CI 0.785-1.249). The best overall RRs were 64% for FOLFIRI + Bev and 62% for mFOLFOX6 + Bev. The common grade 3 or higher adverse events were leukopenia (11% in FOLFIRI + Bev/5% in mFOLFOX6 + Bev), neutropenia (46%/35%), diarrhea (9%/5%), febrile neutropenia (5%/2%), peripheral neuropathy (0%/22%), and venous thromboembolism (6%/2%). The QoL assessed by FACT-C (TOI-PFC) and FACT/GOG-Ntx was favorable for FOLFIRI + Bev during 18 months. CONCLUSION: FOLFIRI plus bevacizumab was non-inferior for PFS, compared with mFOLFOX6 plus bevacizumab, as the first-line systemic treatment for mCRC. CLINICAL TRIALS NUMBER: UMIN000001396.

An in situ hybridization study of perlecan, DMP1, and MEPE in developing condylar cartilage of the fetal mouse mandible and limb bud cartilage.

The main purpose of this in situ hybridization study was to investigate mRNA expression of three bone/cartilage matrix components (perlecan, DMP1, and MEPE) in developing primary (tibial) and secondary (condylar) cartilage. Perlecan mRNA expression was first detected in newly formed chondrocytes in tibial cartilage at E13.0, but this expression decreased in hypertrophic chondrocytes at E14.0. In contrast, at E15.0, perlecan mRNA was first detected in the newly formed chondrocytes of condylar cartilage; these chondrocytes had characteristics of hypertrophic chondrocytes, which confirmed the previous observation that progenitor cells of developing secondary cartilage rapidly differentiate into hypertrophic chondrocytes. DMP1 mRNA was detected in many chondrocytes within the lower hypertrophic cell zone in tibial cartilage at E14.0. In contrast, DMP1 mRNA expression was only transiently detected in a few chondrocytes of condylar cartilage at E15.0. Thus, DMP1 may be less important in the developing condylar cartilage than in the tibial cartilage. Another purpose of this study was to test the hypothesis that MEPE may be a useful marker molecule for cartilage. MEPE mRNA was not detected in any chondrocytes in either tibial or condylar cartilage; however, MEPE immunoreactivity was detected throughout the cartilage matrix. Western immunoblot analysis demonstrated that MEPE antibody recognized two bands, one of 67 kDa and another of 59 kDa, in cartilage-derived samples. Thus MEPE protein may gradually accumulate in the cartilage, even though mRNA expression levels were below the limits of detection of in situ hybridization. Ultimately, we could not designate MEPE as a marker molecule for cartilage, and would modify our original hypothesis.

Increased prevalence of MEFV exon 10 variants in Japanese patients with adult-onset Still's disease.

Autoinflammatory diseases include a large spectrum of monogenic diseases, e.g. familial Mediterranean fever (FMF), as well as complex genetic trait diseases, e.g. adult-onset Still's disease (AOSD). In populations where FMF is common, an increased MEFV mutation rate is found in patients with rheumatic diseases. The aim of this study was to examine MEFV mutations in Japanese patients with AOSD. Genomic DNA was isolated from 49 AOSD patients and 105 healthy controls, and exons 1, 2, 3 and 10 of the MEFV gene genotyped by direct sequencing. MEFV mutation frequencies in AOSD patients were compared with controls. We found no significant difference in overall allele frequencies of MEFV variants between AOSD patients and controls. However, MEFV exon 10 variants (M694I and G632S) were significantly higher in AOSD patients than controls (6.1 versus 0%). In addition, there was no significant difference between MEFV variant carriers and non-carriers with clinical manifestations, but the monocyclic clinical course of the AOSD disease phenotype was observed less frequently in patients without MEFV variants. AOSD patients had significantly higher frequencies of MEFV exon 10 mutations, suggesting that low-frequency variants of MEFV gene may be one of the susceptibility factors of AOSD.

MEFV gene polymorphisms and TNFRSF1A mutation in patients with inflammatory myopathy with abundant macrophages.

Inflammatory myopathy with abundant macrophages (IMAM) has recently been proposed as a new clinical condition. Although IMAM shares certain similarities with other inflammatory myopathies, the mechanisms responsible for this condition remain unknown. Patients with familial Mediterranean fever (FMF) and tumour necrosis factor receptor-associated periodic syndrome (TRAPS) also often develop myalgia. We therefore investigated the polymorphisms or mutations of MEFV and TNFRSF1A genes in patients with IMAM to identify their potential role in this condition. We analysed the clinical features of nine patients with IMAM and sequenced exons of the MEFV and TNFRSF1A genes. The patients with IMAM had clinical symptoms such as myalgia, muscle weakness, erythema, fever and arthralgia. Although none of the patients were diagnosed with FMF or TRAPS, seven demonstrated MEFV polymorphisms (G304R, R202R, E148Q, E148Q-L110P and P369S-R408Q), and one demonstrated a TNFRSF1A mutation (C43R). These results suggest that MEFV gene polymorphisms and TNFRSF1A mutation are susceptibility and modifier genes in IMAM.

Correlation between imatinib pharmacokinetics and clinical response in Japanese patients with chronic-phase chronic myeloid leukemia.

Despite the outstanding results generally obtained with imatinib mesylate (IM) in the treatment of chronic myeloid leukemia (CML), some patients show a poor molecular response. To evaluate the relationship between steady-state trough plasma IM concentration (IM-C(min)) and clinical response in CML patients, we integrated data from six independent Japanese studies. Among 254 CML patients, the mean IM-C(min) was 1,010.5 ng/ml. Importantly, IM-C(min) was significantly higher in patients who achieved a major molecular response (MMR) than in those who did not (P = 0.002). Multivariate analysis showed that an MMR was associated with both age (odds ratio (OR) = 0.97 (0.958-0.995); P = 0.0153) and with IM-C(min) (OR = 1.0008 (1.0003-1.0015); P = 0.0044). Given that patients with IM-C(min) values >1,002 ng/ml had a higher probability of achieving an MMR in our large cohort (P = 0.0120), the data suggest that monitoring of IM levels in plasma may improve the efficacy of IM therapy for CML patients.

Association of distinct clinical subsets with myositis-specific autoantibodies towards anti-155/140-kDa polypeptides, anti-140-kDa polypeptides, and anti-aminoacyl tRNA synthetases in Japanese patients with dermatomyositis: a single-centre, cross-sectional study.

OBJECTIVE: To determine the association of distinct clinical subsets with myositis-specific autoantibodies (MSAs) towards anti-155/140-kDa polypeptides [anti-155/140 antibodies (Abs)], anti-140-kDa polypeptides (anti-140 Abs), and anti-aminoacyl tRNA synthetases (ARS Abs) in Japanese patients with dermatomyositis (DM). METHODS: We compared the clinical features and short-term prognoses of 30 DM patients whose serological status included these MSAs. The MSAs were determined by immunoprecipitation. RESULTS: Anti-155/140 Abs (n = 5), anti-140 Abs (n = 8), and anti-ARS Abs (n = 7) did not overlap each other. All of the anti-155/140 Ab-positive patients (n = 5) were complicated by malignancies, as were all of the anti-140 Ab-positive patients (n = 8), who showed rapidly progressive interstitial lung disease (ILD). The survival rate at 6 months from the diagnosis of DM was significantly lower in the anti-140 Ab-positive patients than in the other patients. CONCLUSION: This is the first study to report, in a single cohort of DM patients, that distinct clinical subsets are distributed in an anti-155/140 Ab-positive group, an anti-140 Ab-positive group, or an anti-ARS Ab-positive group. Our data also confirm previous evidence that anti-155/140 Abs are involved in malignancies and that anti-140 Abs are involved in rapidly progressive ILD.

Calcium/calmodulin-dependent protein kinase II (CaMKII) regulates tumour necrosis factor-related apoptosis inducing ligand (TRAIL)-mediated apoptosis of fibroblast-like synovial cells (FLS) by phosphorylation of Akt.

OBJECTIVE: We tried to determine whether calcium/calmodulin-dependent protein kinase II (CaMKII) regulates tumour necrosis factor-related apoptosis inducing ligand (TRAIL)-mediated apoptosis of fibroblast-like synovial cells (FLS). METHODS: CaMKII expression in FLS was studied by both western blotting and real time reverse transcription polymerase chain reaction (RT-PCR). TRAIL-mediated apoptosis of FLS was quantified by disruption of mitochondrial transmembrane potential (DeltaPsim), Leu-Glu-His-Asp (IETD) ase activity and DNA degradation. Involvement of CaMKII and other kinases, including extracellular signal-regulated kinase (ERK), p38, c-Jun N-terminal kinase (JNK) and Akt during TRAIL-mediated apoptosis of FLS was estimated by the use of specific each kinase chemical inhibitor. RESULTS: Predominant expression of delta and gamma isoform of CaMKII, especially delta isoform, was determined in cultured FLS. TRAIL rapidly induced apoptosis of FLS as well as the phosphorylation of extracellular signal-regulated kinase (ERK), p38, c-Jun N-terminal kinase (JNK) and Akt. Chemical kinase inhibitor toward CaMKII and Akt significantly augmented TRAIL-mediated apoptosis of FLS whereas those toward ERK, p38 and JNK did not. Notably, CaMKII chemical inhibitor abrogated TRAIL-induced phosphorylation of Akt. Elevation of Leu-Glu-His-Asp (IETD) ase activity was associated with the apoptotic phenomena, which was almost suppressed by IETD competitive peptides. CONCLUSION: Our results suggest a first observation that CaMKII regulates TRAIL-mediated apoptosis of FLS through Akt, standing an upstream of caspase-8-dependent cascades. Furthermore, CaMKII is suggested to be a new therapeutic target molecule of rheumatoid arthritis (RA).

Steroid receptor signalling in the brain--lessons learned from molecular imaging.

Studies with green fluorescent protein (GFP) have revealed the subcellular distribution of many steroid hormone receptors to be much more dynamic than previously thought. Fluorescence resonance energy transfer (FRET) and fluorescence recovery after photobleaching (FRAP) are powerful techniques with which to examine protein-protein interaction and the mobility of tagged proteins, respectively. FRET analysis revealed that steroid treatment (with corticosterone or testosterone) induces direct interaction of the glucocorticoid receptor (GR) and importin alpha in the cytoplasm and that, shortly after nuclear entry, the GR detaches from importin alpha. The mineralocorticoid receptor (MR) and androgen receptor (AR) show the same trafficking. Upon oestradiol treatment, ERalpha and ERbeta in the same cell are relocalised to form a discrete pattern and are localised in the same discrete cluster (subnuclear foci). FRAP analysis showed that nuclear ERalpha and ERbeta are most dynamic and mobile in the absence of the ligand, and that mobility decreases slightly after ligand treatment. Genomic as well as non-genomic actions of steroid hormones influence the cellular function of target tissues spacio-temporally.

Direct visualization of glucocorticoid receptor positive cells in the hippocampal regions using green fluorescent protein transgenic mice.

The hippocampal formation is a plastic brain structure important for certain types of learning and memory, and also vulnerable to the effects of stress and trauma. Since hippocampal neurons express high levels of corticosteroid receptor, the morphological changes, including alterations in the size of soma, and the length and number of neurites and spines, in response to glucocorticoids released as a result of stress are intriguing. In order to highlight the morphology of neurons that express glucocorticoid receptor (GR), we have generated a transgenic mouse line expressing green fluorescent protein (GFP) under the control of the GR promoter. We found strong green fluorescence in the pyramidal cell layer of the CA1 and CA2 regions and the granule cell layer of the dentate gyrus of the hippocampus in brain sections of the transgenic mice. GFP fluorescence was observed not only in somas, but also in neurites including both dendrites and axons. In dissociated culture, we also observed GFP fluorescence in the soma, neurites including both dendrites and axons, and dendritic spines. Microtubule-associated protein 2 immunopositive pyramidal-shaped neurons clearly showed two different populations, GFP positive and GFP negative neurons. These results indicate that this transgenic mouse line should be useful for live imaging of neuronal structure in animals as well as GR-positive cultured cells using GFP as a specific indicator.