A pathogenic role for ER stress-induced autophagy and ER chaperone GRP78/BiP in T lymphocyte systemic lupus erythematosus.

Abnormal regulation of ER stress and apoptosis has been implicated in autoimmune disorders. Particularly, ER stress-induced autophagy and the role of GRP78, or BiP in T lymphocyte survival and death in SLE are poorly understood. This study investigated the pathogenic roles of ER stress-induced autophagy and GRP78/BiP in apoptosis of T lymphocytes. We compared spontaneous and induced autophagy and apoptosis of T lymphocytes in healthy donors and patients with SLE. The molecular mechanism of altered autophagy and apoptosis was investigated in T lymphocytes transfected with siRNA for beclin 1 and CHOP and T lymphocytes overexpressing GRP78. Decreased autophagy and increased apoptosis in response to TG-induced ER stress were observed in lupus T lymphocytes. GRP78 and ER stress-signaling molecules, such as PERK, p-eIF2α, IRE1, and ATF6 decreased, whereas CHOP levels increased in lupus T cells in response to TG. The levels antiapoptotic molecules, Bcl-2 and Bcl-XL decreased, whereas the proapoptotic molecules, Bax and caspase 6, increased in lupus T cells. The TG-induced ER stress altered autophagy and apoptosis, which in turn, led to abnormal T cell homeostasis with increased apoptotic T cell death. We hypothesize that aberrant autophagy of T lymphocytes as a result of ER stress and decreased GRP78 expression is involved in the pathogenesis of SLE and might serve as important therapeutic targets.

Increased RANKL-mediated osteoclastogenesis by interleukin-1ß and endoplasmic reticulum stress.

OBJECTIVE: The mechanism by which IL-1ß and thapsigargin (TG)-induced endoplasmic reticulum (ER) stress modulate the receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated osteoclastogenesis remains elusive. Thus, we investigated the osteoclast-specific and ER signals in osteoclastogenesis of bone marrow-derived cells. METHODS: Bone marrow cells (BMCs) were obtained from 5-week-old male ICR mice and cultured to be differentiated into osteoclasts with M-CSF and RANKL in the presence or absence of IL-1ß, TG, or 4-phenylbutyric acid (PBA), an ER stress-reducing drug. The formation of osteoclasts was evaluated by tartrate-resistant acid phosphatase (TRAP) staining and resorption pit assay with a dentine slice. The molecular mechanism of IL-1ß and ER stress in osteoclastogenesis was investigated in BMCs transfected with siRNA for GRP78, PERK and IRE1 using reverse transcription-polymerase chain reaction and immunoblotting for osteoclast-specific and ER stress signaling molecules. RESULTS: IL-1ß and ER stress induced by TG-augmented the formation of osteoclasts, which was significantly inhibited by PBA and was mediated with osteoclast-specific signals, including c-Fos, NFATc1, and ER stress- associated signaling pathways, such as PERK, IRE1, GRP78, and eIF2α. siRNA-mediated knockdown of ER stress signals inhibited the expression of NFATc1 and c-Fos, thus reducing IL-1ß and/or TG-induced formation of osteoclasts. CONCLUSIONS: Osteoclastogenesis by IL-1ß and/or ER stress is mainly associated with upregulation of eIF2α, GRP78, PERK and IRE1. These results suggest that the signaling pathway of ER stress-induced osteoclast formation might be a new therapeutic target to prevent inflammatory and destructive arthritic disease such as RA and diverse osteoporosis.

Efficacy and safety of PG201 (Layla(®)) and celecoxib in the treatment of symptomatic knee osteoarthritis: a double-blinded, randomized, multi-center, active drug comparative, parallel-group, non-inferiority, phase III study.

The objectives of the study are to demonstrate the non-inferiority of PG201 (Layla(®)) 600 mg in comparison with celecoxib 200 mg for the treatment of symptomatic knee osteoarthritis (OA). In total, 309 patients were randomly assigned to receive either the test drug, PG201 600 mg (n = 154) or celecoxib 200 mg (n = 155). The primary efficacy variable was improvement in mean 100-mm pain VAS score from baseline to the final visit (week 8), and this value was compared between the 2 treatment groups. Secondary outcome variables included changes from baseline in the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain VAS score and subscale score, patient's global assessment of disease status quality of life (short form-36) and responder index at weeks 4 and 8. For safety assessment, adverse events were recorded at each clinical visit. At weeks 8, the 100-mm pain VAS scores were significantly decreased in patients receiving both PG201 600 mg (p < 0.0001) and celecoxib 200 mg (p < 0.0001) as compared to the baseline scores; however, no statistically significant differences in these values were noted between the groups (p = 0.312). These results met pre-specified criteria for non-inferiority for both the intent-to-treat and per-protocol populations. PG201 600 mg and celecoxib 200 mg were both well tolerated and no statistically significant differences in the tolerability profile between the groups. PG201 600 mg was as effective and safe as celecoxib 200 mg in the treatment of symptomatic knee OA and might be a useful new medication for the treatment of symptomatic knee OA.

Kaempferol inhibits IL-1ß-induced proliferation of rheumatoid arthritis synovial fibroblasts and the production of COX-2, PGE2 and MMPs.

Inflammatory cytokines, matrix metalloproteinases (MMPs) and cyclooxygenase (COX)-2 released from rheumatoid arthritis synovial fibroblasts (RASFs) are involved in the destruction of both articular bone and cartilage. Kaempferol has been reported to act as an antioxidant and anti-inflammatory agent by inhibiting nitric oxide synthase and COX enzymes. The aim of the present study was to determine the effects of kaempferol on the interleukin-1ß (IL-1ß)-induced proliferation of RASFs and the production of MMPs, COX and prostaglandin E2 (PGE2) by RASFs. The proliferation of the RASFs stimulated with IL-1ß and treated with/without kaempferol was evaluated by CCK-8 assay. The expression of MMPs, TIMP metallopeptidase inhibitor-1 (TIMP-1), COXs, PGE2 and that of intracellular MAPK signaling molecules, including p-ERK, p-p38, p-JNK and nuclear factor-κB (NF-κB) was examined by immunoblotting or semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and ELISA under the conditions described above. Kaempferol inhibited the proliferation of both unstimulated and IL-1ß­stimulated RASFs, as well as the mRNA and protein expression of MMP-1, MMP-3, COX-2 and PGE2 induced by IL-1ß. Kaempferol also inhibited the phosphorylation of ERK-1/2, p38 and JNK, as well as the activation of NF-κB induced by IL-1ß. These results indicate that kaempferol inhibits synovial fibroblast proliferation, as well as the production of and MMPs, COX­2 and PGE2, which is involved in articular inflammation and destruction in rheumatoid arthritis (RA). Our data suggest that kaempferol may be a novel therapeutic agent for the treatment of RA.

Risk factors of severe infections in patients with rheumatoid arthritis treated with leflunomide.

OBJECTIVES: To determine the risk of severe infection requiring or complicating hospitalization associated with leflunomide therapy in patients with rheumatoid arthritis (RA). METHODS: We performed a retrospective study of RA patients who were prescribed leflunomide between 2004 and 2011. Background clinical and laboratory features were compared between patients who suffered severe leflunomide-associated infections and those who did not. RESULTS: Since January 2005, 401 RA patients have started on leflunomide. Among those, 33 (8.2%) developed severe infections: pneumonia, oral candidiasis, pyelonephritis, pulmonary tuberculosis, cellulitis, disseminated herpes zoster, tonsillitis, and pulmonary cryptococcosis. Logistic regression showed that age at entry, the presence of DM, and daily dosage of corticosteroid were associated with development of severe infections. CONCLUSIONS: These results showed that some patients with RA who were taking leflunomide developed severe infections requiring hospitalization, and that older age, DM, and a higher daily dosage of corticosteroid were risk factors associated with leflunomide-associated severe infections.

Successful treatment for conventional treatment-resistant dermatomyositis-associated interstitial lung disease with adalimumab.

Dermatomyositis (DM) is a systemic autoimmune disorder characterized by the inflammation of skeletal muscles and pathognomonic skin rashes, namely heliotrope rash and Gottron's papules and involvement of other organs. Interstitial lung disease (ILD) seems to be one of the most characteristic manifestations of the lung and associated with increased morbidity and mortality in patients with DM. Despite DM-associated ILD requires aggressive therapy with cytotoxic agents, the efficacy is questionable in some cases, and more effective and less toxic therapies are needed. Recently, although there have been several reports of successful treatment of refractory case of PM and DM with the TNF-α antagonists, including infliximab and etanercept, there was no enough evidence for DM-associated ILD. We described herein a patient with DM-associated ILD who had poor response to conventional therapies and successfully treated with adalimumab.

Prevalence of insulin resistance and metabolic syndrome in patients with gouty arthritis.

The study was performed to confirm the high prevalence of metabolic syndrome in gouty patients and to define the relationship between insulin resistance and gouty arthritis. We recruited 83 patients with gouty arthritis and checked clinical factors according to the diagnostic criteria of metabolic syndrome from the ATP III guidelines and WHO Asia-Pacific obesity criteria recommendations. We also assessed the clinical characteristics of subjects and homeostasis model assessment of insulin resistance (HOMA-IR) and compared with previous study groups as controls. The prevalence of metabolic syndrome in patients with gout was 30.1% according to ATP III criteria and 50.6% with WHO Asia-Pacific adjustment and is significantly higher than the previous control study groups (ATP III: 5.2, 10.6%, WHO Asia-Pacific adjustment: 9.8, 13.9%). The mean value of HOMA-IR in patients with gout was 2.63 ± 1.36 and is significantly higher than control study (1.91 ± 1.01, P < 0.05). There were significant correlations between 24-h urinary uric acid excretion and waist circumference (r(2) = 0.225, P = 0.049), fasting insulin (r(2) = 0.241, P = 0.035), and insulin resistance (HOMA-IR) (r(2) = 0.271, P = 0.017). There were significant correlations between insulin resistance and waist circumference (r(2) = 0.341, P < 0.01), BMI (r(2) = 0.390, P < 0.01). The value of HOMA-IR (insulin resistance) and the prevalence of metabolic syndrome in patients with gout are significantly higher than normal healthy control groups. The hyperuricemia in gout might be caused by the increased adiposity associated with insulin resistance.