Inhibiting peripheral and central MAO-B ameliorates joint inflammation and cognitive impairment in rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic inflammation and the destruction of joints and systemic organs. RA is commonly accompanied by neuropsychiatric complications, such as cognitive impairment and depression. However, the role of monoamine oxidase (MAO) and its inhibitors in controlling neurotransmitters associated with these complications in RA have not been clearly identified. Here, we report that peripheral and central MAO-B are highly associated with joint inflammation and cognitive impairment in RA, respectively. Ribonucleic acid (RNA) sequencing and protein expression quantification were used to show that MAO-B and related molecules, such as gamma aminobutyric acid (GABA), were elevated in the inflamed synovium of RA patients. In primary cultured fibroblast-like synoviocytes in the RA synovium, MAO-B expression was significantly increased by tumor necrosis factor (TNF)-α-induced autophagy, which produces putrescine, the polyamine substrate for GABA synthesis. We also observed that MAO-B-mediated aberrant astrocytic production of GABA was augmented by interleukin (IL)-1ß and inhibited CA1-hippocampal pyramidal neurons, which are responsible for memory storage, in an animal model of RA. Moreover, a newly developed reversible inhibitor of MAO-B ameliorated joint inflammation by inhibiting cyclooxygenase (Cox)-2. Therefore, MAO-B can be an effective therapeutic target for joint inflammation and cognitive impairment in patients with RA.

TNF-α Induces Mitophagy in Rheumatoid Arthritis Synovial Fibroblasts, and Mitophagy Inhibition Alleviates Synovitis in Collagen Antibody-Induced Arthritis.

Mitophagy is a selective form of autophagy that removes damaged mitochondria. Increasing evidence indicates that dysregulated mitophagy is implicated in numerous autoimmune diseases, but the role of mitophagy in rheumatoid arthritis (RA) has not yet been reported. The aim of the present study was to determine the roles of mitophagy in patient-derived RA synovial fibroblasts (RASFs) and in the collagen antibody-induced arthritis mouse model. We measured the mitophagy marker PTEN-induced putative kinase 1 (PINK1) in RASFs treated with tumor necrosis factor-α (TNF-α) using Western blotting and immunofluorescence. Arthritis was induced in PINK1-/- mice by intraperitoneal injection of an anti-type II collagen antibody cocktail and lipopolysaccharide. RA severity was assessed by histopathology. PINK1 expression and damaged mitochondria increased in TNF-α treated RASFs via increased intracellular levels of reactive oxygen species. PINK1 knockdown RASFs decreased cellular migration and invasion functions. In addition, PINK1-/- mice with arthritis exhibited markedly reduced swelling and inflammation relative to wild-type mice with arthritis. Taken together, these findings suggest that regulation of PINK1 expression in RA could represent a potential therapeutic and diagnostic target for RA.

Switching from TNFα inhibitor to tacrolimus as maintenance therapy in rheumatoid arthritis after achieving low disease activity with TNFα inhibitors and methotrexate: 24-week result from a non-randomized, prospective, active-controlled trial.

BACKGROUND: Tapering or stopping biological disease-modifying anti-rheumatic drugs has been proposed for patients with rheumatoid arthritis (RA) in remission, but it frequently results in high rates of recurrence. This study evaluates the efficacy and safety of tacrolimus (TAC) as maintenance therapy in patients with established RA in remission after receiving combination therapy with tumor necrosis factor inhibitor (TNFi) and methotrexate (MTX). METHODS: This 24-week, prospective, open-label trial included patients who received TNFi and MTX at stable doses for ≥24 weeks and had low disease activity (LDA), measured by Disease Activity Score-28 for ≥12 weeks. Patients selected one of two arms: maintenance (TNFi plus MTX) or switched (TAC plus MTX). The primary outcome was the difference in the proportion of patients maintaining LDA at week 24, which was assessed using a logistic regression model. Adverse events were monitored throughout the study period. RESULTS: In efficacy analysis, 80 and 34 patients were included in the maintenance and switched arms, respectively. At week 24, LDA was maintained in 99% and 91% of patients in the maintenance and switched arms, respectively (odds ratio, 0.14; 95% confidence interval, 0.01-1.59). Drug-related adverse effects tended to be more common in the switched arm than in the maintenance arm (20.9% versus 7.1%, respectively) but were well-tolerated. CONCLUSION: This controlled study tested a novel treatment strategy of switching from TNFi to TAC in RA patients with sustained LDA, and the findings suggested that TNFi can be replaced with TAC in most patients without the patients experiencing flare-ups for at least 24 weeks. TRIAL REGISTRATION: Korea CDC CRIS, KCT0005868 . Registered 4 February 2021-retrospectively registered.

Mitochondrial Transplantation Modulates Inflammation and Apoptosis, Alleviating Tendinopathy Both In Vivo and In Vitro.

Tendinopathy is a common musculoskeletal condition causing pain and dysfunction. Conventional treatment and surgical procedures for tendinopathy are insufficient; accordingly, recent research has focused on tendon-healing regenerative approaches. Tendon injuries usually occur in the hypoxic critical zone, characterized by increased oxidative stress and mitochondrial dysfunction; thus, exogenous intact mitochondria may be therapeutic. We aimed to assess whether mitochondrial transplantation could induce anti-inflammatory activity and modulate the metabolic state of a tendinopathy model. Exogenous mitochondria were successfully delivered into damaged tenocytes by centrifugation. Levels of Tenomodulin and Collagen I in damaged tenocytes were restored with reductions in nuclear factor-κB and matrix metalloproteinase 1. The dysregulation of oxidative stress and mitochondrial membrane potential was attenuated by mitochondrial transplantation. Activated mitochondrial fission markers, such as fission 1 and dynamin-related protein 1, were dose-dependently downregulated. Apoptosis signaling pathway proteins were restored to the pre-damage levels. Similar changes were observed in a collagenase injection-induced rat model of tendinopathy. Exogenous mitochondria incorporated into the Achilles tendon reduced inflammatory and fission marker levels. Notably, collagen production was restored. Our results demonstrate the therapeutic effects of direct mitochondrial transplantation in tendinopathy. These effects may be explained by alterations in anti-inflammatory and apoptotic processes via changes in mitochondrial dynamics.

Umbilical Cord-Mesenchymal Stem Cell-Conditioned Medium Improves Insulin Resistance in C2C12 Cell.

Background: Umbilical cord-mesenchymal stem cell-conditioned medium (UC-MSC-CM) has emerged as a promising cell-free therapy. The aim of this study was to explore the therapeutic effects of UC-MSC-CM on insulin resistance in C2C12 cell. Methods: Insulin resistance was induced by palmitate. Effects of UC-MSC-CM on insulin resistance were evaluated using glucose uptake, glucose transporter type 4 (GLUT4) translocation, the insulin-signaling pathway, and mitochondrial contents and functions in C2C12 cell. Results: Glucose uptake was improved by UC-MSC-CM. UC-MSC-CM treatment increased only in membranous GLUT4 expression, not in cytosolic GLUT4 expression. It restored the insulin-signaling pathway in insulin receptor substrate 1 and protein kinase B. Mitochondrial contents evaluated by mitochondrial transcription factor A, mitochondrial DNA copy number, and peroxisome proliferator-activated receptor gamma coactivator 1-alpha were increased by UC-MSC-CM. In addition, UC-MSC-CM significantly decreased mitochondrial reactive oxygen species and increased fatty acid oxidation and mitochondrial membrane potential. There was no improvement in adenosine triphosphate (ATP) contents, but ATP synthesis was improved by UC-MSC-CM. Cytokine and active factor analysis of UC-MSC-CM showed that it contained many regulators inhibiting insulin resistance. Conclusion: UC-MSC-CM improves insulin resistance with multiple mechanisms in C2C12 cell.

Fluorometric Imaging for Early Diagnosis and Prognosis of Rheumatoid Arthritis.

Early diagnosis and monitoring of disease progress are of significant importance in the effective treatment of rheumatoid arthritis (RA), because the continuing inflammation can lead to irreversible joint damage and systemic complications. However, applying imaging modalities for the prognosis of RA remains challenging, because no tissue-specific guidelines are available to monitor the progressive course of RA. In this study, fluorometric imaging of RA is reported using bioengineered targeted agents of the blood vessel, bone, and cartilage in combination with the customized optical fluorescence imaging system. Separate but simultaneous tissue-specific images of synovitis, cartilage destruction, and bone resorption are obtained from a mouse model of RA, which allows quantification of the prognosis of diseases at each stage. Thus, the fluorometric imaging of RA by using tissue-specific contrast agents plays a key role in the systemic treatment of RA by monitoring structural damage and disease progression.

Restoration of Cellular Proliferation and Characteristics of Human Tenocytes by Vitamin D.

Vitamin D (Vit D) increases calcium absorption in the intestine after binding to the Vit D receptor (VDR). The VDR has also been identified in muscle cells. Vit D supplementation resulted in improved muscle strength. However, there is a paucity of studies of the role of Vit D on tenocytes. We investigated the effects of Vit D on damaged tenocytes. Human tenocytes were treated with dexamethasone (Dex) to induce cell injury. Expression of the tenocyte-related markers tenomodulin (Tnmd), tenascin C (Tnc), scleraxis (Scx), mohawk (Mkx), and collagen (Col) 1 and 3 were measured. Then, tenocytes were cotreated with Vit D. 1-α-Hydroxylase and VDR were explored in tenocytes. With 10 µM Dex, the growth of tenocytes was significantly inhibited, and the gene expression of Tnmd, Tnc, Scx, Mkx, Col 1 and 3 also decreased. When tenocytes were cotreated with Vit D, cell proliferation recovered in a dose-dependent manner, and the expression of TNMD and Col 1 improved. When studying the mechanisms of the effects of Vit D on tenocytes, reactive oxygen species produced by Dex decreased with Vit D, and the phosphorylation of extracellular signal-regulated kinase and p38 was stimulated by Vit D cotreatment. 1-α-Hydroxylase and VDR were found in tenocytes, indicating that the cells have the ability to use an inactive form of Vit D and interact with it. Vit D is known to perform diverse actions and its protective effects on tenocytes suggest its beneficial role in tendon in addition to muscle and bone. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2241-2248, 2019.

Efficacy and safety of mycophenolate mofetil and tacrolimus combination therapy in patients with lupus nephritis: a nationwide multicentre study.

OBJECTIVES: Recent studies have shown that a combination treatment of mycophenolate mofetil (MMF) and tacrolimus (TAC) may be an option for lupus nephritis (LN) patients that do not adequately respond to initial treatment. We evaluated the efficacy and safety of the combination treatment of MMF and TAC in LN patients with suboptimal response to prior MMF or TAC treatments. METHODS: In this multicentre study, we retrospectively enrolled 62 patients with class III, IV, or V LN who inadequately responded to MMF or TAC treatment. Those patients were then treated with a combination of MMF and TAC for 6 months. The primary outcome was complete remission (CR) at 6 months, and secondary outcomes included overall response and adverse events. RESULTS: After 6 months of treatment with the drug combination, CR was achieved in 14 of 62 patients (22.6%), and 35 (56.5%) patients responded. A significant reduction in proteinuria and lupus disease activity score was observable after 3 months. After 1 year, the CR rate increased to 36.4% (20 of 55 patients), and the overall response rate (n=38, 69.1%) also increased from 6 months. Twenty-one patients reported 29 adverse events, including severe infection requiring hospitalisation (n=3, 10.3%), infection not requiring hospitalisation (n=2, 6.9%), and herpes zoster (n=4, 13.8%). CONCLUSIONS: Our findings suggest that a combined MMF and TAC treatment, with a favourable adverse-event profile, may be a beneficial option for LN patients with inadequate response to either MMF or TAC treatments.

Dendritic Cell Immunotherapy Combined with Cytokine-Induced Killer Cells Effectively Suppresses Established Hepatocellular Carcinomas in Mice.

BACKGROUND: The response of hepatocellular carcinoma (HCC) to immunotherapy is often disappointing and new strategies are clearly needed. The aim of the present study was to investigate whether cytokine-induced killer (CIK) cells combined with a dendritic cell vaccination enhanced cytotoxicity against hepatocarcinoma tumor cells in an in vivo animal model. METHODS: CIKs and DCs were prepared from C3H/HeJ mice by conventional methods, the dendritic cell (DC) pulsed with a MH134 cell lysate, DC or CIK alone were used as controls. Cell phenotypes were analyzed by flow cytometry, cytokine secretion levels were determined by enzyme-linked immunosorbent assay (ELISA), and cytotoxicity was assessed by means of an in vitro lactate dehydrogenase (LDH) release assay. A mouse hepatocarcinoma cell MH134-bearing mice model was established to test the in vivo anti-tumor efficacy of the system. RESULTS: CIK cells combined with DC therapy resulted in significant inhibition of tumor growth compared with the control group, whereas the decrease in tumor growth in mice that had been treated with CIK or DC alone did not reach the level of statistical significance. The combination therapy led to a further increase in the population of cytotoxic T cells (CTLs) in vivo, compared to the CIK or DC alone therapy. In addition, the combination therapy significantly enhanced cytotoxic activity against MH134 cells. CONCLUSION: Taken together, these results show that a DC + CIK vaccination is more effective than DC or CIK alone therapy for the treatment of hepatocarcinoma cancer.

Rosiglitazone-mediated dendritic cells ameliorate collagen-induced arthritis in mice.

Rosiglitazone is a selective ligand for peroxisome proliferator-activated receptor-gamma (PPAR-γ), which serves diverse biological functions. A number of autoimmune disease models have been used to examine the anti-inflammatory and immunosuppressive effects of tolerogenic dendritic cells (tDCs). The aim of the present study was to investigate whether rosiglitazone-mediated DC (Rosi-DC) therapy suppressed arthritis in a collagen-induced arthritis (CIA) mouse model. Rosi-DCs were generated by treating immature DCs with TNF-α, type II collagen, and rosiglitazone. CIA mice then received subcutaneously (s.c.) two injections of Rosi-DCs. The severity of arthritis was then assessed histopathologically. The phenotypes of the DC and regulatory T (Treg) cell populations in CIA mice were determined by flow cytometry and the effect of Rosi-DCs on the secretion of autoimmunity-inducing cytokines was examined by ELISA. Rosi-DCs expressed lower levels of DC-related surface markers than mature DCs. Histopathological examination revealed that the degree of inflammation in the paws of Rosi-DC-treated mice was much lower than that in the paws of PBS-treated CIA mice. Taken together, these results clearly show that rosiglitazone-mediated DCs ameliorate CIA, most likely via the induction of antigen-specific Treg cells.

Hemophagocytic syndrome diagnosed by liver biopsy in a female patient with systemic lupus erythematosus.

Hemophagocytic syndrome (HPS) is a rare but potentially fatal disease caused by the activation of benign macrophage in various organs including bone marrow and the mononuclear phagocytes system. Here we report a case of 23-year-old woman in whom HPS occurred along with lupus flare during follow-up after the diagnosis of systemic lupus erythematosus. The patient showed aggravated malar rash, discoid rash, febrile cytopenia, hyperferritinemia, and elevated liver enzymes. She underwent ultrasound-guided percutaneous gun biopsy of the liver using an 18-gauge needle. As activated macrophages with hemophagocytosis were confirmed in hepatic histology, the patient was diagnosed as having reactive HPS related to a lupus flare. Clinical symptoms and laboratory findings were improved through high-dose intravenous methylprednisolone therapy followed by oral prednisolone and cyclosporine maintenance therapy. In lupus patients with persistent high fever, cytopenia, elevated levels of serum ferritin, and liver enzymes, reactive HPS should be strongly suspected, and aggressive examinations such as liver biopsy need to be considered for early diagnosis and proper treatment.

Tuberculin reaction is not attenuated in patients with rheumatoid arthritis living in a region with intermediate burden of tuberculosis.

Tuberculin reactions in patients with immunocompromised conditions have been reported to be attenuated compared with healthy controls. In the case of rheumatoid arthritis (RA), several studies have reported conflicting results. We performed this study to evaluate the tuberculin reaction in patients with RA in a region with intermediate burden of tuberculosis. Eighty-one RA patients and 104 age- and sex-matched controls who underwent tuberculin skin test (TST) at Severance Hospital in Seoul, South Korea were reviewed. TST was carried out using the Mantoux method. Indurations larger than 10 mm were considered positive. Information about risk factors for latent tuberculosis infection was acquired. The mean age of the patients with RA was 48 ± 14 years, and the median disease duration was 9 (1-203) months. The mean DAS28 was 5.22 ± 0.13. The control group consisted of healthy living donors for liver transplantation and the patients with diseases not related with immunosuppression. BCG vaccination, close contact history with active tuberculosis, and history of pulmonary tuberculosis were not different between the two groups. The positive rate of TST (34.6% vs. 38.5%) and the median skin induration size (5 mm vs. 6 mm) of the two groups were similar. Medications and DAS28 were not associated with the TST result. The tuberculin reaction of patients with RA is not attenuated compared with that of controls in South Korea.

Predictive factors related to progression toward rheumatoid arthritis in Korean patients with undifferentiated arthritis.

Some patients with undifferentiated arthritis (UA) experience spontaneous remission; however, one-third of patients progress to rheumatoid arthritis (RA) in the final process of the disease. This study evaluated clinical variables in order to find a prediction model that could predict the development of RA in patients with UA. The medical records of 164 patients, who were initially diagnosed with undifferentiated arthritis in Yonsei University Medical Center from January 2004 to December 2007, were retrospectively reviewed. They were followed up for at least 6 months. The clinical variables related to the development of RA were identified by univariate analyses. Using logistic regression analysis, the prediction model was made and the diagnostic performance of the model was evaluated. Thirty-two patients of the 164 total patients progressed to RA during the follow-up period. The prediction model was composed of clinical factors including the duration of morning stiffness, the number of tender joints, the number of swollen joints, C-reactive protein level, rheumatoid factor, anti-cyclic citrullinated peptide antibody, and erosive change on baseline X-ray. The prediction score ranged from 0 to 10. All of the patients with a higher prediction score greater than five experienced RA progression. The area under the curve value for the prediction rule was 0.976. The prediction model could predict progression to RA in patients with UA. It especially helps the clinician to decide on a management plan for patients with a high prediction score.

Serum calprotectin as a marker for disease activity and severity in adult-onset Still's disease.

OBJECTIVE: Calprotectin is a calcium-binding cytosolic protein of the neutrophil, monocyte, and macrophage, and its secretion increases during activation of these cells. Our objective was to measure serum calprotectin concentrations in patients with adult-onset Still's disease (AOSD) and to correlate serum calprotectin with the activity and severity of AOSD. METHODS: We enrolled 25 patients with AOSD and 30 age- and sex-matched healthy controls. Thirty-one serum samples were obtained from patients with AOSD during active or inactive disease and were assayed for calprotectin by ELISA. Clinical and laboratory data related to disease activity and severity were collected at the same time, and systemic scores for disease severity were calculated. RESULTS: Mean calprotectin levels in patients with AOSD were significantly higher than in controls (57.11 +/- 25.38 ng/ml vs 34.90 +/- 4.85 ng/ml, respectively; p < 0.05). Patients with active AOSD had a significantly higher mean calprotectin level than those with inactive disease (61.26 +/- 25.59 ng/ml vs 35.32 +/- 5.90 ng/ml; p < 0.05). Calprotectin levels decreased significantly after treatment in all 6 patients with AOSD from whom followup samples were obtained (p = 0.028). Serum calprotectin showed strong correlations with serum ferritin (r = 0.686, p < 0.001), lactate dehydrogenase (r = 0.647, p < 0.001), leukocyte count (r = 0.774, p < 0.001), aspartate aminotransferase (r = 0.387, p = 0.042), and C-reactive protein (r = 0.588, p = 0.001), but not with erythrocyte sedimentation rate, arginine aminotransferase, hemoglobin, or platelet count. Serum calprotectin showed a significant correlation with AOSD systemic scores, reflecting disease severity (r = 0.803, p < 0.001). CONCLUSION: Serum calprotectin increased in patients with AOSD, in close correlation with disease activity and severity. These findings suggest that serum calprotectin can provide a reliable clinical marker for monitoring the disease activity and severity of AOSD.

Serum amyloid a as a useful indicator of disease activity in patients with ankylosing spondylitis.

PURPOSE: To investigate whether serum amyloid A (SAA) levels are increased in patients with ankylosing spondylitis (AS) and whether its levels correlate well with AS disease activity. MATERIALS AND METHODS: Thirty-eight patients with AS and 38 age- and sex-matched control subjects were enrolled in this cross-sectional study. Their SAA levels were quantitatively measured by immunonephelometry. An established, self-administered instrument for evaluating disease activity (Bath Ankylosing Spondylitis Disease Activity Index, BASDAI) was used to measure and acute phase reactants, including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), in patients with AS. RESULTS: Patients with AS had a significantly higher mean SAA level than controls (9.52 +/- 7.49mg/L versus 2.73 +/- 1.57mg/L, p < 0.05), and the mean BASDAI score of patients with elevated SAA levels was significantly higher than that of patients with normal SAA levels (5.6 +/- 1.3 versus 4.4 +/- 1.5, p < 0.05). SAA levels showed significant correlations with BASDAI scores (r=0.431, p=0.007), ESR (r=0.521, p=0.001) and CRP levels (r=0.648, p < 0.001). Additionally, the correlation between ESR and CRP levels also appeared significant (r=0.703, p < 0.001). In those with normal ESR or CRP levels, SAA levels and BASDAI scores were elevated (p < 0.05) and showed a trend of positive correlation with one another. CONCLUSION: Our data showed that SAA levels were increased in patients with AS and correlated well with disease activity. These findings suggest that SAA can be used as a valuable indicator of disease activity in AS.

Malignancies in Korean patients with inflammatory myopathy.

The aim of this study was to assess the prevalence and the common type of malignancies in Korean patients with polymyositis (PM) and dermatomyositis (DM) and to evaluate the differences of clinical and laboratory findings between patients with malignancy and those without malignancy. Forty-one Korean patients, who were diagnosed as PM or DM, were enrolled in this study. They fulfilled the Bohan and Peter's criteria for a definite diagnosis of PM and DM. Patients with PM were 25 and those with DM were 16. Eleven out of 41 patients (26.8%) had malignancies. The malignancy was diagnosed simultaneously or later in 81.8% of patients with inflammatory myopathy (IM). The breast cancer was the most common malignancy. In this study, forty three years old as a screening age for malignancy had 88.9% sensitivity and 50.2% specificity. The serum levels of creatine kinase (CK) were significantly lower in patients with malignancy than those without malignancy.