Regional differences in the prevalence of sensitization to environmental allergens: Analysis on IgE antibody testing conducted at major clinical testing laboratories throughout Japan from 2002 to 2011.

BACKGROUND: Identification of sensitized allergens for patients with respiratory allergy is an important step in disease care and environmental allergen control. The Japanese archipelago belongs to various climate categories due to its length from north to south which transverse the subarctic in the north to the subtropical in the south, suggesting substantial regional differences in dominant environmental allergens. However, few studies have assessed the regional differences in the prevalence of sensitization to environmental allergens. METHODS: We requested three major clinical testing laboratories to provide us with summarized results of antigen-specific IgE-antibody (Ab) measurements. These measurements were collected for clinical purposes throughout Japan from 2002 through 2011. The prevalence of positivity for IgE-Ab against 19 environmental allergens was calculated for each prefecture in order to evaluate regional differences. RESULTS: Test data on specific IgE-Ab of 19,969,753 orders were analyzed. The prevalence of positivity for house dust mites was high and the regional difference was low, whereas apparent regional differences were found for pollen, insects, and fungi. The prevalence of positivity for Japanese cedar was low in Hokkaido and Okinawa, while those to alder was highest in Hokkaido. Higher prevalence for insects was observed in southern areas (Okinawa and prefectures in Kyusyu). CONCLUSIONS: Findings of this study clearly demonstrated regional differences in the prevalence of sensitization to environmental allergens in Japan and the study also provides useful information for the clinician when deciding which allergens should preferentially be measured for IgE-Ab after considering regional difference.

[Four Cases of Resected cN2 Stage III A Non-Small-Cell Lung Cancer after Induction Chemotherapy].

Four patients with non-small-cell lung cancer(NSCLC), diagnosed with cN2 stage III A disease, by using CT and FDG-PET/ CT imaging, received 2 or 3 courses of platinum-based combination chemotherapy.The patients achieved partial response after chemotherapy and underwent surgery.Complete tumor resection was performed via upper lobectomy for 3 patients, but in 1 patient, interlobar metastatic lymph nodes remained after middle and lower bilobectomy.Two courses of postoperative chemotherapy were administered to 3 patients, but 1 patient could not receive postoperative chemotherapy due to complications.One patient, in whom lymph node metastasis completely disappeared after induction chemotherapy, is still alive and without disease recurrence for 7 years.Another patient, with the presence of only one intralobar metastatic lymph node after chemotherapy, died of brain and meningeal metastases, 3 years after surgery.Two other patients, with multiple pN2 lymph nodes after chemotherapy, died of early intrathoracic local relapse, indicating that prognosis is influenced by response to chemotherapy, especially in patients with poor N-downstaging.Improvements in response to induction therapy by using intensive chemotherapeutic regimens, concurrent radiotherapy, and strict patient selection, limited to N-downstaged cases, are needed for successful surgery outcomes in patients with cN2 stage III A NSCLC who have received induction therapy.

Lower Airway Inflammation in Eosinophilic Chronic Rhinosinusitis as Determined by Exhaled Nitric Oxide.

BACKGROUND: Chronic rhinosinusitis (CRS) is classified into eosinophilic CRS (ECRS) and non-ECRS. The objectives of this study were to evaluate lower airway inflammation by measuring the fractional concentration of exhaled nitric oxide (FeNO) and to examine the effects of endoscopic sinus surgery (ESS) on FeNO in patients with ECRS compared to non-ECRS. METHODS: CRS patients with nasal polyps (23 with ECRS and 22 with non-ECRS) were enrolled into this study. ECRS was diagnosed based on the definition proposed by the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) study group. Several clinical markers including blood eosinophil counts, percent of eosinophils in white blood cells (WBC), number of eosinophils in nasal polyps, JESREC scores, total IgE, FeNO, and Lund-Mackay paranasal sinus CT scores were compared between ECRS and non-ECRS. These markers were also tested before and 2 months after ESS. RESULTS: FeNO was significantly higher in patients with ECRS than in non-ECRS patients. When all CRS patients were tested, a significant correlation was found between FeNO and eosinophilic markers including blood eosinophil counts, percent of eosinophils in WBC, number of eosinophils in nasal polyps, and JESREC scores. FeNO showed a significant correlation with Lund-Mackay scores only in ECRS patients. Blood eosinophil counts, percent of eosinophils in WBC, and FeNO decreased after ESS only in ECRS patients. CONCLUSIONS: ECRS patients had lower airway inflammation as revealed by an elevated FeNO, which was parallel to the Lund-Mackay CT scores. ESS decreased the blood eosinophils and FeNO, leading to an improvement of the occult pulmonary dysfunction in ECRS patients.

Limited Azithromycin Localization to Rabbit Meibomian Glands Revealed by LC-MS-Based Bioanalysis and DESI Imaging.

Meibomian gland dysfunction (MGD) is the leading cause of dry eye, and although it affects approximately 4% of the population, treatment options remain limited. Topical azithromycin is one of the most promising pharmacological agents because of its multiple mechanisms of action and long sustainability. Azithromycin is frequently used as an off-label medication in the U.S. However, although azithromycin is presumed to act directly on meibomian gland cells, the mechanisms of action that contribute to its clinical efficacy remain unclear because no studies using a pharmacokinetic approach have been performed. Therefore, we aimed to clarify whether topical azithromycin reaches the meibomian glands sufficiently to generate a biological effect. We measured azithromycin concentrations in rabbit meibomian glands collected using a recently developed method. Moreover, we also visualized the azithromycin micro-distribution using desorption electrospray ionization (DESI) imaging. Azithromycin concentration in the meibomian glands reached only 0.8 µg/g tissue following a single application of a 1% azithromycin ophthalmic solution and was 1000-fold lower than the concentration in conjunctival epithelium. Similarly, no signal was observed in the meibomian glands on DESI images. Our results clearly demonstrated that topical azithromycin had limited access to the meibomian glands and was predominantly distributed in ocular surface tissues such as the palpebral conjunctiva and lid margins. These findings provide new insight into the clinical responses to topical azithromycin therapy and will aid in the further development of effective drugs with more suitable pharmacokinetic properties.

Problems of elderly patients on inhalation therapy: Difference in problem recognition between patients and medical professionals.

BACKGROUND: There is no systematic analysis to identify problems involved with instruction on inhalation therapy for elderly patients. We conducted a nationwide questionnaire survey for patients and medical professionals. METHODS: A questionnaire survey was conducted of adult patients on inhaled drugs (ages 18-92 years, 820 individuals) and medical professionals (pharmacists or nurses) who provided instruction on inhalation therapy to these patients in 23 institutions in Japan to investigate the technique and the level of understanding (knowledge) of the inhalation therapy. Changes in the recognition of performance of inhalation technique and inhalation knowledge with increasing age were analyzed. RESULTS: According to patients' subjective assessment, there was no deterioration in the performance of the inhalation technique or loss of the knowledge with increasing age. On the other hand, medical professionals' objective assessment revealed a significant loss of both inhalation technique and knowledge with increasing age. Not many elderly patients noticed their own problems themselves, revealing a great perception gap between elderly patients and medical professionals. Thus, there was concern that patients would unconsciously practice the inhalation procedure improperly. On the other hand, in comparison with non-elderly patients, elderly patients were less resistant to continuation of therapy, suggesting that they would be more likely to accept instruction on inhalation therapy. CONCLUSIONS: Elderly patients are apt to assume that they "understand well", therefore, in order to recognize and close the perception gap between elderly patients and medical professionals, it is necessary to provide them with more aggressive (frequent) instructions on inhalation therapy.

[Long-Term Local Control with Radiofrequency Ablation or Radiotherapy for Second, Third, and Fourth Lung Tumors after Lobectomy for Primary Lung Cancer].

A 78-year-old woman developed second, third, and fourth lung tumors at intervals of 1-3 years after left upper lobectomy for primary lung cancer. The tumors were controlled with radiofrequency ablation(RFA)or conventionalconformalradiotherapy for 9 years postoperatively. For the treatment of second primary lung cancer or lung metastasis after surgical resection of the primary lung cancer, reoperation is not recommended because of the impaired respiratory reserve. Thus, local therapy such as radiotherapy or RFA is applied in some cases. Among these, stereotactic body radiotherapy(SBRT)is a feasible option because of its good local control and safety, which is comparable with surgery. On the other hand, for cases of multiple lesions that are not suitable for radiotherapy or combination therapy, RFA could be an option because of its short-term local control, easiness, safety, and repeatability. After surgery for primary lung cancer, a second lung tumor could be controlled with highly effective and minimally invasive local therapy if it is recognized as a local disease but is medically inoperable. Therefore, longterm postoperative follow-up for primary lung cancer is beneficial.

[Pulmonary Mucoepidermoid Carcinoma--A Case Report].

Mucoepidermoid carcinoma (MEC) of the lungs is a rare type of lung cancer, mainly arising from the submucosal salivary type mucous glands of the large bronchi. MEC is classified into low- and high-grade subtypes based on its cytological and histological features, and this classification correlates well with prognosis. We report the case of a 36-year-old man diagnosed after an initial episode of obstructive pneumonia. CT and bronchoscopy revealed an endobronchial mass in the right S3 bronchus and distal atelectasis. Although biopsy is important for deciding the treatment plan, both pre- and intraoperative biopsy resulted in false negativity in this patient. The tumor was completely resected via right upper lobectomy, and the final pathological diagnosis was low-grade MEC. No evidence of disease was found 2 years after the operation without any adjuvant therapy. At (11; 19) translocation with the associated CRTC1-MAML2 fusion oncogene is often recognized in cases of both salivary and pulmonary MEC. It is speculated that MEC is sensitive to EGFR-TKI therapy, which disrupts CRTC1-MAML2-induced proliferation signals via upregulation of the EGFR ligand amphiregulin.

[Post-recurrence survival after surgical resection of non-small cell lung cancer with local recurrence].

We retrospectively evaluated the clinical outcomes of 192 consecutive patients with local recurrence after complete resection of non-small cell lung cancer NSCLC). The initial local recurrent site was the resection stump in 5 patients the chest wall in 3 patients, mediastinum in 1 patient, and diaphragm in 1 patient), and the hilar and/or mediastinal lymph node (HMLN) in 17 patients. The sites of distant metastasis were the lungs in 10 patients, pleura in 4 patients, brain in 7 patients, liver in 5 patients, bone in 4 patients, and other sites in 4 patients. Treatments after initial recurrence included surgery in 2 patients, radiotherapy in 5 patients, chemotherapy in 9 patients, and chemo-radiotherapy in 5 patients. Only 1 patient received supportive care. The response to radiotherapy was a complete response (R) in 1 patient, partial response (PR) in 5 patients, stable disease (SD )in 3 patients, and progressive disease (PD )in 1 patient. The best response of all lines of chemotherapy was CR in 3 patients, PR in 4 patients, SD in 3 patients, and PD in 4 patients. The median post-recurrence survival (PRS) time with local recurrence was better than that with distant metastasis (23 vs 14 months); however, the best PRS was obtained in patients with recurrence in the lungs (29 months). A CR for more than 2 years was obtained in 1 patient after surgery, in 1 patient after radiotherapy, and in 2 patients after chemotherapy. Although local recurrence of resected NSCLC can be potentially controlled by using local treatments - such as surgery and radiotherapy - or systemic chemotherapy, curative aggressive treatment should be considered when required.

[A case of small-sized lung cancer complicated by sarcoidosis].

A woman in her seventies presented with bilateral hilar and mediastinal lymphadenopathy with high fluorodeoxyglucose (FDG) uptake by positron emission tomography (PET)-computed tomography (CT), small lung nodules, and uveitis. Mediastinoscopic biopsy yielded a histological finding of epithelioid granuloma and a diagnosis of sarcoidosis. A nodule, 1 cm in diameter, in the right middle lobe with moderate FDG uptake was deemed to be a sarcoidosis lesion. Steroid therapy for uveitis resulted in shrinkage of the hilar and mediastinal lymph nodes; however, 1 year later the nodule in the right middle lobe had enlarged to 2 cm in diameter. Right middle lobectomy was performed, and a histological diagnosis of lung squamous cell carcinoma was made. Six months later, right pretracheal lymphadenopathy with high FDG uptake was noted and was proved to be a metastatic squamous cell carcinoma by endobronchial ultrasound-guided transbronchial needle aspiration( EBUS-TBNA). After 7 courses of chemotherapy with docetaxel, the target lesion shrank and its abnormal FDG uptake disappeared. Small-sized lung cancer could be missed when complicated by sarcoidosis because the latter produces a background of multiple lesions, so careful diagnostic imaging and follow-up should be performed in patients diagnosed as having sarcoidosis.

Differential effects of Akt pathway inhibitors on IL-1ß-induced protein phosphorylation in human fibroblast-like synoviocytes.

CONTEXT: Interleukin (IL)-1ß activates various signal transduction pathways including p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and Akt in human fibroblast-like synoviocytes (HFLS). OBJECTIVE: We investigated the effects of an Akt inhibitor, a phosphatidylinositol 3-kinase (PI3K) inhibitor, and Akt RNAi knockdown on IL-1ß-induced protein phosphorylation in HFLS to clarify the role of the PI3K/Akt signaling pathway in the phosphorylation of the inhibitor of κB (IκB)α and heat shock protein 27 (HSP27). MATERIALS AND METHODS: A multiplex suspension array system was used for the detection of phosphorylated proteins. RESULTS: IL-1ß induced biphasic phosphorylation of IκBα, with the first phase occurring 10 min after IL-1ß stimulation, and this was augmented by treatment with Akt inhibitor IV. However, this phenomenon was not observed after treatment with LY-294002, a PI3K inhibitor. Furthermore, Akt inhibitor IV suppressed ERK2 phosphorylation, whereas LY-294002 and Akt RNAi had no effect. In contrast, Akt inhibitor IV, LY-294002, and Akt RNAi augmented HSP27 phosphorylation. DISCUSSION AND CONCLUSIONS: Modulation of different stages of the PI3K/Akt pathway may differentially affect the phosphorylation of IκBα and HSP27 in HFLS.

Synthesis and pharmacological evaluation of 1,1,3-substituted urea derivatives as potent TNF-alpha production inhibitors.

A three substituted urea derivative, SA13353 (compound 1a), exhibited potent inhibitory activity against lipopolysaccharide (LPS)-induced TNF-alpha production. We focused on the 1,1-substituted moiety (R(1) and R(2)) of SA13353 and investigated substituent effects of this moiety on LPS-induced TNF-alpha production by oral administration in rats. The synthesis of the urea derivatives was performed rapidly in a one-pot manner using a manual synthesizer. Several compounds containing hydrophobic substituents at this moiety showed more potent inhibitory activities than SA13353.

Effects of SA13353, a transient receptor potential vanilloid 1 agonist, on leukocyte infiltration in lipopolysaccharide-induced acute lung injury and ovalbumin-induced allergic airway inflammation.

We recently demonstrated that SA13353, a transient receptor potential vanilloid 1 (TRPV1) agonist, reduced the severity of the symptoms of kidney injury, arthritis, and encephalomyelitis in disease models. Here, we investigated the effects of orally administered SA13353 on leukocyte infiltration in lipopolysaccharide (LPS)-induced acute lung injury and ovalbumin-induced allergic airway inflammation. In LPS-induced lung injury, SA13353 attenuated neutrophil infiltration and the increase of TNF-alpha and CINC-1 levels. In allergic airway inflammation, SA13353 tended to inhibit leukocyte infiltration and attenuated the increase of IL-4 and IL-12p40. These results suggest that somatosensory TRPV1 may play an anti-inflammatory role in lung inflammation.

Role of leukotriene B4 in 5-lipoxygenase metabolite- and allergy-induced itch-associated responses in mice.

We investigated the role of leukotriene (LT) B(4) in 5-lipoxygenase metabolite- and allergy-induced itch-associated responses using SA6541, an LTA(4) hydrolase inhibitor. Itch-associated responses were induced by intradermal injection of 5-hydroperoxyeicosatetraenoic acid (HPETE), a precursor of 5-lipoxygenase metabolites, and passive cutaneous anaphylaxis in ICR mice. By screening molecules related to arachidonic acid metabolism or pruritus, SA6541 was found to be a specific inhibitor of LTA(4) hydrolase. Pharmacokinetic studies confirmed the specificity of SA6541 at an oral dose of 100 mg/kg in mice. 5-HPETE induced scratching behavior, which was inhibited by SA6541 (100 mg/kg). However, SA6541 (100 mg/kg) hardly attenuated the 5-HPETE-induced increase in vascular permeability. Moreover, SA6541 (100 mg/kg) partially attenuated scratching behavior, but did not affect the increase in vascular permeability caused by passive cutaneous anaphylaxis. On the other hand, ketotifen fumarate, a histamine H1 antagonist, strongly inhibited the scratching behavior and the increase in vascular permeability caused by passive cutaneous anaphylaxis. These results suggest that LTB(4) is an endogenous itch mediator in the skin and is involved in the pruritus response in allergic reactions.

Combined effects of bucillamine and etanercept on a rat type II collagen-induced arthritis model.

The combined effects of bucillamine (Buc) and etanercept (ETN) on a rat model of type II collagen (CII)-induced arthritis (CIA) after treatment onset were investigated. In the combination treatment, rats received Buc 30 mg/kg orally administered once daily from the onset of arthritis or from 4 days after the onset of arthritis and ETN 0.3 mg/kg subcutaneously administered once on the day of onset. The effects of monotherapy with Buc and ETN, respectively, and of Buc + ETN combination therapy on the resulting polyarthritis were evaluated by histopathological analyses and measurements of hindpaw volumes, serum anti-collagen antibody and immunoglobulin levels, and cytokine levels. The Buc + ETN therapeutic combination reduced hindpaw swelling, synovial proliferation, bone destruction, new bone formation, and inflammatory cell infiltration in CIA. Montherapy with Buc showed a tendency to ameliorate these symptoms, while monotherapy with ETN reduced hindpaw swelling at 4 days after administration but did not maintain treatment efficacy toward the end of the experimental period. Histopathological findings did not reveal any efficacy of the ETN therapy. ETN alone increased the serum immunoglobulin levels, while its combination with Buc reduced these levels. Similar results were obtained for serum anti-CII antibody titers. The Buc + ETN combination treatment also reduced serum interleuking (IL)-1alpha and granulocyte macrophage colony-stimulating factor and tended to reduce serum IL-1beta and IL-6 levels. These results suggest that a combination therapy of Buc and ETN may be effective for the treatment of rheumatoid arthritis (RA).

Preventive effect of SA13353 [1-[2-(1-adamantyl)ethyl]-1-pentyl-3-[3-(4-pyridyl)propyl]urea], a novel transient receptor potential vanilloid 1 agonist, on ischemia/reperfusion-induced renal injury in rats.

Tumor necrosis factor (TNF)-alpha plays a crucial role in the pathogenesis of ischemia/reperfusion-induced renal injury. We demonstrated recently that the preischemic treatment with resiniferatoxin, a transient receptor potential vanilloid 1 (TRPV1) agonist, attenuates renal TNF-alpha mRNA expression and improves ischemia/reperfusion-induced renal injury in rats. In addition, we found that SA13353 [1-[2-(1-adamantyl)ethyl]-1-pentyl-3-[3-(4-pyridyl)propyl]urea], a novel orally active TRPV1 agonist, inhibits TNF-alpha production through the activation of capsaicin-sensitive afferent neurons and reduces the severity of symptoms in established rat collagen-induced arthritis. In the present study, we investigated effects of treatment with SA13353 on ischemia/reperfusion-induced renal injury in rats. Ischemic acute kidney injury (AKI) was induced by occlusion of the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after contralateral nephrectomy. Renal function in vehicle-treated AKI rats markedly decreased at 24 h after reperfusion. Treatment with SA13353 (3, 10, and 30 mg/kg p.o.) 30 min before ischemia dose-dependently attenuated the ischemia/reperfusion-induced renal dysfunction. Histopathological examination of the kidney of AKI rats revealed severe renal damage, which were significantly suppressed by the SA13353 treatment. In renal tissues exposed to ischemia/reperfusion, neutrophil infiltration, superoxide production, TNF-alpha mRNA expression, and cytokine-induced neutrophil chemoattractant-1 mRNA expression were augmented, but these alterations were attenuated by the treatment with SA13353. On the other hand, ischemia/reperfusion-enhanced renal interleukin-10 mRNA expression and its plasma concentration were further augmented by SA13353 treatment. These results demonstrate that the orally active TRPV1 agonist SA13353 prevents the ischemia/reperfusion-induced AKI. This renoprotective effects seem to be closely related to the inhibition of inflammatory response via TRPV1 activation.

The investigation of synovial genomic targets of bucillamine with microarray technique.

OBJECTIVE: To identify the molecular mechanisms of bucillamine activity, global gene expression analysis and pathway analysis were conducted using IL-1 beta-stimulated human fibroblast-like synovial cells (FLS). METHODS: Normal human FLS were treated with IL-1 beta in the presence or absence of 10 and 100 microM bucillamine for 6 h. Total RNA was extracted and global gene expression levels were detected using a 44 k human whole genome array. Data were analyzed using Ingenuity pathway analysis. RESULTS: Numerous pathways were activated by IL-1 beta stimulation. At both concentrations, bucillamine suppressed nine signal pathways stimulated by IL-1 beta. CONCLUSIONS: Bucillamine effectively inhibited fibroblast growth factor (FGF) signaling and tight junction signaling activated by IL-1 beta in FLS. Suppression of these signal pathways may correlate with the pharmacologic mechanisms of bucillamine. In particular, the suppression of FGF signaling by bucillamine is remarkable because the activation of FGF signaling may be involved in rheumatoid arthritis pathology.

Synthesis and biological evaluation of N-mercaptoacylcysteine derivatives as leukotriene A4 hydrolase inhibitors.

We studied synthetic modifications of N-mercaptoacylamino acid derivatives to develop a new class of leukotriene A(4) (LTA(4)) hydrolase inhibitors. S-(4-Dimethylamino)benzyl-l-cysteine derivative 2a (SA6541) showed inhibitory activity against LTA(4) hydrolase (IC(50), 270nM) and selectivity over other metallopeptidases except angiotensin-converting enzyme (ACE, IC(50), 520nM). Modification at the para-substituent of the phenyl ring of compound 2a improved LTA(4) hydrolase inhibitory activity as well as selectivity over ACE. Finally, we obtained S-(4-cyclohexyl)benzy-l-cysteine derivatives 11l and 16i as potent and selective LTA(4) hydrolase inhibitors.

Point mutation of tyrosine 759 of the IL-6 family cytokine receptor, gp130, augments collagen-induced arthritis in DBA/1J mice.

BACKGROUND: Knock-in mice (gp130F759) with a Y759F point mutation in gp130, a signal transducing receptor subunit shared by members of the IL-6 cytokine family, show sustained activation of STAT3, enhanced acute-phase or immune responses, and autoimmune arthritis. We conducted a detailed analysis of collagen-induced arthritis (CIA) in gp130F759 with a DBA/1J background (D/J.gp130F759). METHODS: We backcrossed gp130F759 to C57BL/6 and DBA/1J, and compared the pathologic changes, including occurrence of arthritis, in the two distinct genetic backgrounds. We analyzed CIA in D/J.gp130F759 and investigated the effects of methotrexate (MTX) on CIA. RESULTS: C57BL/6 background gp130F759 mice, but not D/J.gp130F759, spontaneously developed polyarthritis and glomerulonephritis. On the other hand, keratitis of the eyes only developed in D/J.gp130F759, indicating the influence of genetic background on disease development in gp130F759 mice. Resistance of the DBA/1J background against spontaneous arthritis urged us to examine CIA in D/J.gp130F759. CIA in D/J.gp130F759 was more severe, with greater bone destruction, than the control mice. After collagen immunization, splenomegaly and serum levels of rheumatoid factor and anti-DNA antibody were augmented in D/J.gp130F759. Bio-Plex analysis of serum cytokines revealed increased IL-12p40 and PDGF-BB before immunization, and increased levels of IFN-gamma, IL-17, TNF-alpha, IL-9, and MIP-1beta 8 days after the booster dose. IL-6 and PDGF-BB in D/J.gp130F759 showed distinct kinetics from the other cytokines; higher levels were observed after arthritis development. MTX partially attenuated the development of arthritis and inhibited bone destruction in D/J.gp130F759, with reduction of anti-type II collagen antibody levels, suggesting that MTX mainly affects antigen-specific immune responses in CIA. CONCLUSION: The Tyr-759 point mutation of the IL-6 family cytokine receptor subunit, gp130, caused autoimmune disease, and this was also influenced by the genetic background. CIA in D/J.gp130F759 is useful for evaluating drugs in a relatively short period because sustained activation of STAT3 may enhance the disease symptoms.

IL-6-PAD4 axis in the earliest phase of arthritis in knock-in gp130F759 mice, a model for rheumatoid arthritis.

Objective: Animal models for human diseases are especially valuable for clarifying molecular mechanisms before or around the onset. As a model for rheumatoid arthritis (RA), we utilise knock-in mice gp130F759. They have a Y759F mutation in gp130, a common receptor subunit for interleukin 6 (IL-6) family cytokines. Definitive arthritis develops around 8 months old and the incidence reaches 100% around 1 year old. Careful examination in the clinical course revealed very subtle resistance in flexibility of joints at 5 months old. Therefore, pathophysiological changes in gp130F759 were examined to dissect molecular mechanisms for preclinical phase of RA. Methods: Severity of arthritis in gp130F759 was evaluated with a clinical score system and histological quantification. Serum cytokines, autoantibodies and C reactive protein (CRP) were measured. Changes in the synovium were analysed by real-time PCR, flow cytometry and immunohistochemistry. Results: Around 5 months old, various types of cytokines, rheumatoid factor (RF), anti-circular citrullinated peptide IgM and CRP increased in the sera of gp130F759. Enhancement of neovascularisation, synovial hyperplasia and fibrosis was observed. Also, increases in haematopoietic cells dominated by innate immune cells and gene expression of Il6 and Padi4 were detected in the joints. Il6 was expressed by non-haematopoietic synovial cells, whereas PAD4 protein was detected in the synovial neutrophils. Padi4 is induced in neutrophils in vitro by IL-6. Increases of phospho-STAT3 and PAD4 protein were detected in the synovium. Deletion of IL-6 in gp130F759 normalised the amount of PAD4 protein in the joints. Conclusion: The IL-6-PAD4 axis operates in the earliest phase of arthritis in gp130F759, implicating it in early RA.

SA13353 (1-[2-(1-Adamantyl)ethyl]-1-pentyl-3-[3-(4-pyridyl)propyl]urea) inhibits TNF-alpha production through the activation of capsaicin-sensitive afferent neurons mediated via transient receptor potential vanilloid 1 in vivo.

Tumor necrosis factor-alpha (TNF-alpha) is known to play a crucial role in the pathogenesis of rheumatoid arthritis. In the present study, we demonstrate the effects of SA13353 (1-[2-(1-Adamantyl)ethyl]-1-pentyl-3-[3-(4-pyridyl)propyl]urea), a novel orally active inhibitor of TNF-alpha production, in animal models, and its mechanism of action on TNF-alpha production. SA13353 significantly inhibited lipopolysaccharide (LPS)-induced TNF-alpha production in a dose-dependent manner in rats. Moreover, SA13353 exhibited a binding affinity for the rat vanilloid receptor and increased neuropeptide release from the rat dorsal root ganglion neurons. However, its effects were blocked by pretreatment with the transient receptor potential vanilloid 1 (TRPV1) antagonist capsazepine. The ability of SA13353 and capsaicin to inhibit LPS-induced TNF-alpha production was eliminated by sensory denervation or capsazepine pretreatment in vivo. Although they inhibited LPS-induced TNF-alpha production in mice, these effects were not observed in TRPV1 knockout mice. SA13353 provoked the release of neuropeptides without nerve inactivation, even when chronically administered to rats. These results suggest that SA13353 inhibits TNF-alpha production through activation of capsaicin-sensitive afferent neurons mediated via TRPV1 in vivo. Post-onset treatment of SA13353 strongly reduced the hindpaw swelling and joint destruction associated with collagen-induced arthritis in rats. Thus, SA13353 is expected to be a novel anti-arthritic agent with a unique mechanism of action.