Inhibition of 6-phosphofructo-2-kinase suppresses fibroblast-like synoviocytes-mediated synovial inflammation and joint destruction in rheumatoid arthritis

BACKGROUND AND PURPOSE

Abnormal glycolytic metabolism contributes to joint inflammation in rheumatoid arthritis (RA). The aims of this study were to investigate the role of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), a bifunctional enzyme that controls the glycolytic rate, in regulating fibroblast-like synoviocyte (FLS)-mediated synovial inflammation and invasiveness in RA.

EXPERIMENTAL APPROACH

A specific inhibitor of PFKFB3, PFK15, and siRNA were used to evaluate the role of PFKFB3. Protein expression was measured by Western blotting or immunofluorescence staining. The expression of cytokines was determined by quantitative real-time PCR. Migration and invasion were measured using a Boyden chamber assay. A mouse model of collagen-induced arthritis (CIA) was used to evaluate the in vivo effect of PFK15.

KEY RESULTS

PFKFB3 expression was increased in the synovial tissue and FLSs from RA patients compared with osteoarthritis patients. PFKFB3 inhibition decreased the expression of IL-8, IL-6, CCL-2 and CXCL-10 and the proliferation, migration and invasion of RA FLSs. PFK15 suppressed TNF-α-induced activation of NF-κB and p38, JNK and ERK MAPK signals in RA FLSs. PFK15 treatment also suppressed glucose uptake and lactate secretion. Lactate reversed the inhibitory effect of PFK15 or PFKFB3 siRNA on cytokine expression and migration of RA FLSs. Lactate was also involved in PFKFB3-mediated activation of NF-κB and MAPKs. Intraperitoneal injection of PFK15 in mice with CIA attenuated joint inflammation.

CONCLUSION AND IMPLICATIONS

Elevated PFKFB3 expression might contribute to synovial inflammation and aggressive behaviours of RA FLSs, suggesting a novel strategy of targeting PFKFB3 to prevent synovial inflammation and joint destruction in RA.

Piperlongumine Suppresses Dendritic Cell Maturation by Reducing Production of Reactive Oxygen Species and Has Therapeutic Potential for Rheumatoid Arthritis

Piperlongumine (PLM) is a natural product from the plant Piper longum that inhibits platelet aggregation, atherosclerosis plaque formation, and tumor cell growth. It has potential value in immunomodulation and the management of autoimmune diseases. In this study, we investigated the role of PLM in regulating the differentiation and maturation of dendritic cells (DCs), a critical regulator of immune tolerance, and evaluated its clinical effects in a rheumatoid arthritis mouse model. We found that PLM treatment reduced LPS-induced murine bone marrow-derived DC maturation, characterized by reduced expression of CD80/86, secretion of MCP-1, IL-12p70, IL-6, TNFα, IFN-γ, and IL-23, and reduced alloproliferation of T cells; however, PLM does not affect cell differentiation. Furthermore, PLM reduced intracellular reactive oxygen species (ROS) production by DCs and inhibited the activation of p38, JNK, NF-κB, and PI3K/Akt signaling pathways. Conversely, PLM increased the expression of GSTP1 and carbonyl reductase 1, two enzymes that counteract ROS effects. ROS inhibition by exogenous N-acetyl-l-cysteine suppressed DC maturation. PLM treatment improved the severity of arthritis and reduced in vivo splenic DC maturation, collagen-specific CD4(+) T cell responses, and ROS production in mice with collagen-induced arthritis. Taken together, these results suggest that PLM inhibits DC maturation by reducing intracellular ROS production and has potential as a therapeutic agent for rheumatoid arthritis.

Infection in Southern Chinese Patients with Systemic Lupus Erythematosus: Spectrum, Drug Resistance, Outcomes, and Risk Factors

Objective.

To investigate the spectrum, antibiotic-resistant pattern, risk factors, and outcomes of infection in patients hospitalized with systemic lupus erythematosus (SLE).

Methods.

We collected the clinical and microbiological data from hospitalized patients with SLE with infection between June 2005 and June 2015, and then conducted retrospective analyses.

Results.

Among our sample of 3815 hospitalized patients, 1321 (34.6%) were diagnosed with infection. The majority (78.3%) of infection occurred within 5 years of SLE onset. Bacterial infection was predominant (50.6%), followed by viral infection (36.4%) and fungal infection (12.5%). The lungs (33.7%) and upper respiratory tracts (26.3%) were most commonly affected. Gram-negative bacteria (GNB) were predominant over gram-positive bacteria (178 isolates vs 90 isolates). The most frequently isolated bacteria were Escherichia coli (24.6%), followed by Acinetobacter baumannii (13.4%) and coagulase-negative Staphylococcus (13.4%). Multidrug-resistant (MDR) strains were detected in 26.9% of bacterial isolates. The most common fungus was Candida spp. (99 episodes), followed by Aspergillus (24 episodes) and Cryptococcus neoformans (13 episodes). The overall mortality rate for this cohort was 2.2%; 48 patients died of infection. Factors associated with bacterial and viral infection were higher Systemic Lupus Erythematosus Disease Activity Index, renal involvement, thrombocytopenia, accumulated dose of glucocorticoids (GC), and treatment with cyclophosphamide (CYC). Renal involvement, accumulated dose of GC, and treatment with CYC were associated with fungal infection.

Conclusion.

Infection was the leading cause of mortality in patients hospitalized with SLE. There were some notable features of infection in Chinese patients including early onset, higher proportion of respiratory tract involvement, predominance of GNB with emergence of MDR isolates, and a variety of pathogens.

A Rare Case of Disseminated Tuberculosis of the Bone Marrow in Systemic Lupus Erythematosus: Case Report

Patients with systemic lupus erythematosus (SLE) are susceptible to tuberculosis (TB), especially in endemic areas such as China. The variable and nonspecific clinical features of disseminated TB often leads to an erroneous or misdiagnosis. When a patient presents with TB of the bone marrow, the clinical condition is more perplexing and the prognosis is typically poor. Till now, there is no case report after apatinib came in the market.Here, we report a case of TB of the bone marrow accompanied with SLE. The patient exhibited remarkable features, including widespread lesions in the lungs, spinal vertebrae, sacrum, and ilium that were found to be consistent with TB of the bone marrow after histopathological examination.This case highlights the importance of clinical suspicion for TB during the follow-up of SLE patients, especially in endemic areas. An aggressive diagnostic biopsy should be performed in suspected TB patients as early as possible.

Incidence and predictive factors for malignancies with dermatomyositis: a cohort from southern China

OBJECTIVES

We aimed to explore the incidence of malignancy in dermatomyositis and assess the potential risk factors of occurrence of malignancy in DM from southern China.

METHODS

A retrospective cohort study of patients admitted in the 1st affiliated university hospital between 2003 and 2012 was performed. Demographic information, clinical symptoms, laboratory findings, medications were documented. The endpoint of the study was defined as occurrence of malignancy or death.

RESULTS

For this approximately 10-year retrospective study, 60 out of 246 dermatomyositis patients developed malignancies with the overall incidence of 24.4%. Nasopharyngeal carcinoma (NPC) and ovarian carcinoma were the most common malignant disease, accounting for 35% (21/60) and 15% (9/60) of malignancies, respectively. Lung and colon were followed as the third most common carcinoma (5 out of 60, 8.3%). Among these 60 patients with malignancies, 39 (65.0%, 39/60) cases occurred within 1 year after DM diagnosis. Subsequently, malignancies were detected in 13 (21.7%, 13/60) patients during the second year and 8 (13.3%, 8/60) during the third year. One patient developed cancer at the 35th month after DM as the latest. The logistic regression multivariate analysis indicated that male gender [odds ratio (OR) = 3.76, 95% confidence interval (CI ) 1.86~7.61, p<0.01], dysphagia (OR= 2.21, 95%CI 1.10~4.48, p=0.03) and elevated erythrocyte sedimentation rate (ESR) (OR= 2.37, 95% CI 1.18~4.75, p=0.02) were risk factors for the occurrence of malignancies, while interstitial lung disease (ILD) acted as a protective factor (OR=0.13, 95%CI 0.06~0.28, p<0.01).

CONCLUSIONS

It was necessary to carry out routine malignancy screening for Chinese DM patients due to its high incidence. Nasopharyngeal carcinoma and ovarian cancer were the most common malignant disease. The risk of malignancy was highest in the first year after DM diagnosis and reduced thereafter. Extensive work-ups for malignancy screening should be carried out at the first year. Male gender, dysphagia and elevated ESR were risk factors for occurrence of malignancy. The presence of ILD could diminish the risk of coexisting of malignancy.

[Assessment of ovarian reserve with anti-Müllerian hormone in female patients with systemic lupus erythematosus]

OBJECTIVE

To evaluate the serum level of anti-Müllerian hormone (AMH) in female patients with systemic lupus erythematosus (SLE) and identify its correlations with age and cyclophosphamide (CYC) therapy.

METHODS

A total of 77 SLE female patients and 38 control healthy women with regular menstrual cycles were recruited. AMH was measured by enzyme linked immunosorbent assay (ELISA) kit. Follicle-stimulating hormone (FSH), estradiol (E2) and antral follicle count (AFC) of bilateral ovary were detected at the third day of menstrual cycle.

RESULTS

Their mean age was (29 ± 5) years (range, 20-40) and the mean duration (2.7 ± 2.4) years. The mean serum level of AMH was (1.5 ± 1.3) µg/L and AFC 10 ± 7. Linear regression revealed AFC (r = 0.9, P < 0.01) was associated with the level of AMH. The mean levels of AMH and AFC were significantly higher in patients naїve to CYC therapy than in those under exposure, but lower than that in healthy control (P < 0.01). No difference existed in FSH and E2 among 3 groups. Compared with those above 30 years old, the patients aged 30 years and younger had significantly higher level of AMH (P < 0.01). The Spearman's correlation analysis indicated that each 5 gm of CYC exposure were independently associated with a lower level of AMH (r = -0.4, P < 0.01).

CONCLUSION

As a more sensitive marker of ovarian reserve, AMH is associated with age and the cumulative dose of CYC. SLE patients aged >30 years and under exposure to CYC >10 g should be closely monitored for potential adverse events.

Increased phosphorylation of ezrin is associated with the migration and invasion of fibroblast-like synoviocytes from patients with rheumatoid arthritis

OBJECTIVE

Increasing evidence indicates that the cytoskeletal protein ezrin may play a critical role in cell motility. This study aims to investigate the role of ezrin in regulating the migration and invasion of fibroblast-like synoviocytes (FLSs) from patients with RA.

METHODS

Synovial tissues were obtained from 12 patients with RA and 6 with OA, and then FLSs were separated from synovial tissues. The expression of ezrin and phosphorylated ezrin (p-ezrin) was examined by Western blotting or IF staining. A specific inhibitor of ezrin phosphorylation and small interference RNA-mediated ezrin knockdown were used to inhibit the phosphorylation of ezrin. Migration and invasion of FLSs in vitro were measured by the Boyden chamber assay.

RESULTS

Increased expression of p-ezrin protein was found in synovial tissue and FLSs in patients with RA compared with patients with OA. Stimulation with TNF-α and IL-1β increased ezrin phosphorylation in RA FLSs. Inhibition of p-ezrin protein by a specific inhibitor of phosphorylation of ezrin and small interfering RNA-mediated knockdown reduced in vitro migration and invasion, as well as actin stress fibre formation in RA FLS. Furthermore, rho kinase and p38 mitogen-activated protein kinase (MAPK) signal pathways were involved in the phosphorylation of ezrin and invasion of RA FLSs.

CONCLUSION

Increased expression of p-ezrin may contribute to aberrant aggressive behaviours of RA FLSs, which are mediated by rho kinase and the p38 MAPK pathway. This suggests a novel strategy targeting phosphorylation of ezrin to prevent synovial invasiveness and joint destruction in RA.

Subclinical impairment of ovarian reserve in systemic lupus erythematosus patients with normal menstruation not using alkylating therapy

BACKGROUND

Disease activity is a major factor in menstrual disorders in systemic lupus erythematosus (SLE) patients not receiving alkylating therapy. However, the ovarian reserve of SLE women with normal menstruation is still unclear.

METHODS

Twenty-three SLE patients naïve to cytotoxic agents (SLE group) and nineteen SLE patients receiving current or previous cyclophosphamide (CTX) therapy (without other cytotoxic agents; SLE-CTX group) were enrolled. Twenty-one age-matched healthy women served as controls. All patients and controls had a regular menstrual cycle. Basal hormone levels, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and anti-Müllerian hormone (AMH), and antral follicle count (AFC) were analyzed in the two study groups and compared with the control group.

RESULTS

No significant differences were found between the SLE, SLE-CTX, and control groups in age, body mass index (BMI), and basal FSH and LH levels. The E2 (P=0.023) levels were high and the AMH (P=0.000) values and AFC (P=0.001) were significantly lower in the SLE and SLE-CTX groups compared to control. However, these values were similar between the SLE and SLE-CTX groups.

CONCLUSION

SLE patients not receiving alkylating therapy who had normal menstruation and short illness duration still had an impaired ovarian reserve.

Association of thiopurine methyltransferase status with azathioprine side effects in Chinese patients with systemic lupus erythematosus

Azathioprine (AZA) is indicated for the treatment of systemic lupus erythematosus (SLE). Thiopurine methyltransferase (TPMT) is the rate-limiting enzyme in the steps of AZA metabolization. Heritable deficiency of TPMT enzyme activity and polymorphisms may lead to leukopenia. This study aims to detect TPMT polymorphisms and TPMT enzyme activity in Chinese SLE patients and to describe the association between TPMT genotypes and adverse effects of AZA. One hundred and twenty-six SLE patients with present or previous thiopurine therapy were identified from a local database. Adverse effects were documented. No TPMT*2, TPMT*3A, or TPMT*3B mutant alleles were detected. TPMT*3C was detected in four patients (3.17 %). The heterozygotes had significantly lower mean TPMT activity as compared to the homozygotes (2.38 ± 1.24 vs. 12.56 ± 7.02 U/mL, P < 0.001). Twenty-seven cases (21.42 %) exhibited adverse effects. All of the heterozygotes (4/4, 100 %) developed severe leukopenia, and three cases (3/4, 75 %) of whom exhibited alopecia simultaneously. The specificity of TPMT*3C for predicting leukopenia and alopecia was 100 and 99.17 %, respectively, and the sensitivity was 28.57 and 60.00 %, respectively. The mean value of TPMT activity with leukopenia (4.67 ± 3.01 vs. 13.2 ± 6.94 U/mL RBC, P < 0.001) or alopecia (2.31 ± 1.16 vs. 12.65 ± 6.98 U/mL RBC, P < 0.001) was significantly lower than those without. TPMT*3C was the most common mutant polymorphism found in the study group. TPMT activity is reduced in TPMT*3C mutant. AZA-induced leukopenia and alopecia were partly correlated to TPMT*3C heterozygotes and low TPMT activity. The results of this study suggest that the value of TPMT genotyping before AZA therapy was limited in Chinese SLE patients, considering the low sensitivity. Routine monitoring of TPMT activity before prescribing and continuous hematological monitoring dose were recommended.

Clinical Features and Associated Factors of Abdominal Pain in Systemic Lupus Erythematosus

Objective.

To evaluate the clinical characteristics of systemic lupus erythematosus (SLE)-induced abdominal pain in a cohort in South China and identify the risk factors for SLE-induced abdominal pain.

Methods.

This is a retrospective cohort study of SLE patients with complaint of abdominal pain admitted to the first affiliated university hospital of Sun Yat-sen University between 2002 and 2011. Demographic information, clinical features, laboratory findings, SLE Disease Activity Index, and imaging characteristics were documented.

Results.

Of the 3823 SLE patients reviewed, 213 patients complained of abdominal pain and 132 cases were considered SLE-induced. The most common causes were lupus mesenteric vasculitis (LMV; 73.5%, 97/132) and lupus pancreatitis (LP; 17.4%, 23/132). Other causes included appendicitis, acute gastroenteritis, and peritonitis. Univariate and multivariate logistic regression analysis indicated the European Consensus Lupus Activity Measurement (ECLAM) score was significantly associated with lupus-induced abdominal pain (OR = 1.858, 95% CI: 1.441–2.394, p < 0.001), LMV (OR = 1.713, 95% CI: 1.308-2.244, p < 0.001), and LP (OR = 2.153, 95% CI: 1.282, 3.617, p = 0.004). The serum D-dimer level (OR = 1.004, 95% CI: 1.002-1.005, p < 0.001) was a strongly associated factor for lupus-induced abdominal pain. Moderate and large amounts of ascetic fluid was significantly associated with lupus-induced abdominal pain and LMV. Elevated liver enzymes was a risk factor for LP (OR = 34.605, 95% CI: 3.591-333.472, p = 0.002).

Conclusion.

LMV and LP were the leading causes of SLE-induced abdominal pain. The serum D-dimer was a strongly associated factor for lupus-induced abdominal pain. ECLAM score was a reliable index in assessment of SLE-associated abdominal pain. Elevated liver enzymes, and moderate or large amounts of ascites, were positively associated with lupus-induced abdominal pain.

[Modulation of RhoA/Rho kinase on migration, invasion and proliferation of fibroblast like synoviocytes from patients with rheumatoid arthritis]

OBJECTIVE

To evaluate the modulation of RhoA/Rho kinase (ROCK), a small Rho GTPase, on migration, invasion and proliferation of fibroblast like synoviocytes (FLS) from rheumatoid arthritis (RA) patients.

METHODS

RA FLS were collected from active RA patients. And 10% fetal bovine serum (FBS) and interleukin-1β (IL-1β) were used as stimuli in migration and proliferation experiments respectively. RhoA activity was measured by pull down assay while ROCK activity by Western blot. FLS migration and invasion in vitro were measured by the Transwell chamber method. And thiazolyl blue tetrazolium bromide (MTT) test was used to detect cell proliferation.

RESULTS

There were increased activities of RhoA and ROCK in ex vivo FLS from RA versus OA patients and healthy control. The migrated cell number of FBS-induced, C3-treated and Y27632-treated groups was 85 ± 14, 51 ± 15 and 42 ± 11 respectively. The Matrigel invading cell number of 3 groups was 64 ± 13, 39 ± 12 and 26 ± 9 respectively. Statistical differences existed in cell number between FBS-induced, C3-treated or Y27632-treated group (P < 0.05) in above migration and invasion experiments. Inhibition of RhoA and ROCK activity also suppressed the cytoskeletal reorganization and proliferation of RA FLS.

CONCLUSION

Increased RhoA/ROCK activity may contribute to abnormal migration, invasion and proliferation of RA FLS. Thus inhibition of ROCK activity may be a new therapeutic target for RA.

[Associated factors for the occurrence of lupus enteritis]

OBJECTIVE

To explore the clinical and laboratory characteristics of patients with lupus enteritis to provide rationales for clinical diagnosis and treatment.

METHODS

A retrospective group control study was conducted for systemic lupus erythematosus (SLE) patients with complaints of acute abdominal pain from 2004 to 2011. They were divided into 2 groups: lupus enteritis (n = 66) and non-lupus related abdominal pain (n = 73). The associated factors included demographic, laboratory, clinical and radiographic data.

RESULTS

Lupus enteritis (39.3%) was the most common cause of lupus patients with acute abdominal pain. There were no differences in autoantibody profiles, complement, erythrocyte sedimentation rate, C reactive protein and SLE disease activity index (SLEDAI) score between two groups. The level of D-dimer and European consensus lupus activity measurement (ECLAM) score were significantly higher in the group of lupus enteritis than those in non-lupus related gastrointestinal injury. Lupus enteritis had significantly higher percentage of complications with multiple serous cavity effusions and ascites. But after adjusting with logistic regression multivariate analysis, only the level of D-dimer, ECLAM and volume of ascites were associated with occurrence of lupus enteritis.

CONCLUSION

Lupus enteritis is the most common cause of acute abdominal pain. D-dimer is an excellent predictor for lupus abdominal pain. As compared with SLEDAI, ECLAM may be more suitable for assessment in SLE patients with alimentary tract injury.

Role of p21-activated kinase 1 in regulating the migration and invasion of fibroblast-like synoviocytes from rheumatoid arthritis patients

OBJECTIVE

To investigate the role of p21-activated kinase 1 (PAK1) in regulating migration, invasion and MMP expression in RA fibroblast-like synoviocytes (FLS).

METHODS

RA FLS migration and invasion in vitro were measured by the Boyden chamber method. Invasion of RA FLS into cartilage was detected in the severe combined immunodeficiency (SCID) mouse co-implantation model of RA in vivo. PAK1 and MT1-MMP expression were examined by western blotting. ELISA was used to measure the production and activity of MMPs.

RESULTS

Phosphorylated PAK1 (p-PAK1) protein expression was increased in ex vivo synovial membrane cells from RA patients. Stimulation with IL-1β or TNF-α up-regulated p-PAK1 expression. Inhibition of PAK1 by transfection with dominant negative PAK1 mutant (dnPAK1) reduced in vitro migration and invasion of RA FLS. In the SCID mouse model, RA FLS invasion into cartilage was attenuated by transfection with dnPAK1 in vivo. PAK1 regulated IL-1β-induced production and activity of MMP-13 and MT1-MMP. Inhibition of MMP-13 or MT1-MMP activity also reduced RA FLS invasion. Furthermore, dnPAK1 transfection inhibited c-Jun N-terminal kinase (JNK) activation, but did not affect the activities of extracellular signal-regulated kinases and p38. Inhibition of the JNK activity by chemical inhibitor significantly reduced the migration, invasion and production of MMP-13 and MT1-MMP.

CONCLUSION

PAK1 plays an important role in regulating the migration, invasion and production and activity of MMPs in RA FLS, which is mediated by the JNK pathway. This suggests a novel strategy targeting PAK1 to prevent joint destruction of RA.

Activation of farnesoid X receptor attenuates liver injury in systemic lupus erythematosus

To investigate the expression and effect of farnesoid X receptor (FXR) on systemic lupus erythematosus (SLE) liver dysfunction and indicate its hepatoprotective role and the immunomodulatory property. mRNA and protein levels of FXR were determined on the liver specimens of SLE patients with liver injury as well as MRL/lpr rodent models. The FXR agonist chenodeoxycholic acid (CDCA) was administrated to MRL/lpr mice and the control BALB/C with concanavalin A (ConA)-induced liver injury. Blood samples were taken 0, 4, 8, 12, 16, and 24 h after ConA injection for the detection of serum ALT, AST, IFN-γ, TNF-α, and IL-6. FXR was down-regulated at both mRNA and protein levels in the liver specimens of SLE patients with liver injury as well as MRL/lpr mice. MRL/lpr was more susceptible to ConA than BALB/C indicated by significantly higher levels of aminotransferase and inflammatory cytokines. Activation of FXR by CDCA significantly reduced aminotransferase and inflammatory cytokines IFN-γ, TNF-α, and IL-6 caused by ConA injection in MRL/lpr mice. FXR was down-regulated in SLE patients as well as MRL/lpr lupus models with liver dysfunction. FXR activation ameliorated liver injury and suppressed inflammatory cytokines, thereby showing its protective function in SLE. Our findings raised the promising potential target for the treatment of SLE liver injury.

[Modulation of RhoA/ROCK pathway on TLR-2 ligand-induced chemokine secretion in fibroblast-like synoviocytes from patients with rheumatoid arthritis]

OBJECTIVE

To evaluate the modulation of RhoA/Rho kinase (ROCK) signaling pathway, a small Rho GTPase that is considered as an important modulator in inflammatory responses, on Toll-like receptor-2 mediated chemokine secretion in fibroblast-like synoviocytes (FLS) from rheumatoid arthritis (RA) patients.

METHODS

The RhoA activity was measured by a pull-down assay. And the ROCK activity was assessed by Western blot. The secretion of chemokines was measured by ELISA (enzyme-linked immunosorbent assay). MTT test was used to detect the cellular viability.

RESULTS

The stimulation of peptidoglycan (PG, 5 mg/L) increased the levels of IL-8 (interleukin-8), RANTES (regulated upon activation normal T cell expressed & secreted) and MCP-2 (monocyte chemotactic protein-2) and boosted the activities of RhoA and ROCK versus the unstimulated RA FLS. And these effects of PG were suppressed by anti-TLR-2 monoclonal antibody. Inhibition of RhoA and ROCK with a specific inhibitor inhibited the secretion of IL-8, RANTES and MCP-2 in PG-induced RA FLS.

CONCLUSION

The present study provides novel evidence that the RhoA/ROCK signal pathway modulates the TLR-2-mediated secretion of chemokines in RA FLS. It suggests that the inhibition of RhoA/ROCK may be a new therapeutic approach for RA.

Treatment efficacy of etanercept and MTX combination therapy for ankylosing spondylitis hip joint lesion in Chinese population

To investigate the efficacy of etanercept and MTX (methotrexate) combination therapy in Chinese patients with ankylosing spondylitis hip joint lesion, the possible courses and maintenance protocol, altogether 97 ankylosing spondylitis patients fulfilling the modified New York criteria with hip joint lesion were enrolled in a 12-month trial treated with combined etanercept and MTX. All these patients were required to be poor responders to SSZ (Sulfasalazine) or MTX therapy for 6 consecutive months or the longer. Etanercept was administered subcutaneously twice a week at a fixed dosage of 25 mg for the first six months, followed by 25 mg once a week in patients with good control of both symptoms and radiological progression, or twice a week for another six months in patients with BASDAI > or = 4. Combined MTX was administered intravenously once a week at the dosage of 15 mg. Demographics, clinical and laboratory features, physical function and quality of life using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), Harris hip score, and radiological assessment using the BASRI-hip index were recorded. Most patients achieved pain release at the end point of assessment. Significant improvement in Bath AS Disease Activity Index (BASDAI) (P < 0.05), Bath AS Functional Activity Index (BASFI) (P < 0.05), and Harris hip score (P < 0.05) was demonstrated. Radiographic progression was recorded as no exacerbation or alleviated. Larger interval between two etanercept administrations would provide similar advantages to standard method and possibly less adverse events if MTX was combined. Etanercept and MTX combination therapy was beneficial to ankylosing spondylitis patients with hip joint lesion, and staged dosage deduction in the long term proved to be effective as well as adverse event preventing.

[Clinical analysis of 6 cases of systemic lupus erythematosus complicated by transverse myelitis]

OBJECTIVE

To summarize the clinical features and therapeutic approach of systemic lupus erythematosus (SLE) complicated by transverse myelitis (TM).

METHODS

The clinical characteristics, laboratory examinations, treatment and prognosis of 6 SLE cases with TM were retrospectively analyzed with review of the literatures.

RESULTS

The 6 patients consisted of 5 females and 1 male aged 14 to 36 years (mean 23 years). The mean duration from symptom onset of SLE to TM was 8 months (1 to 13 months). All the patients had lower limb hypodynamia, and 3 of them developed upper limb hypodynamia. MRI scanning of the spine identified lesions in the cervical spinal cord in 2 cases, thoracic lesions in 3 cases, and multiple involvement of the cervical, thoracic and lumbar cord in 1 case. Examination of the cerebrospinal fluid yielded no specific findings except for leukocytosis in 1 case and hypoglycemia in another. Five cases were treated with high-dose MP+CTX, and the other case was treated with MP (80 mg/day)+CTX. Five patients responded favorably to the treatment, while the other showed no obvious improvement.

CONCLUSION

TM is a rare complication of SLE affecting mostly young patients and occurring in the early stage of the disease. Early diagnosis and aggressive treatment might improve the prognosis.

Increased phosphorylation of ezrin/radixin/moesin proteins contributes to proliferation of rheumatoid fibroblast-like synoviocytes

OBJECTIVES

Increasing evidence indicates that ezrin/radixin/moesin (ERM) proteins may play a critical role in cell proliferation. This study examined the role of ERM proteins in proliferation of fibroblast-like synoviocytes (FLS) from patients with RA.

METHODS

Synovial tissues (STs) were obtained from 18 RA and 6 OA patients. The expression of ERM and its phosphorylated proteins in cultured FLS and ST was assessed by western blots or IF staining. Small interference RNA (siRNA)-mediated ERM knockdown was used to inhibit phosphorylation of ERM. Proliferation of FLS was measured by bromodeoxyuridine (BrdU) incorporation into cell DNA and by PCNA immunoblotting.

RESULTS

Our study showed that increased phosphorylation of ERM proteins was found in ST and FLS from patients with RA as compared with OA patients and non-arthritis controls. Treatment with TNF-α, IL-1β or PDGF-induced phosphorylation of ERM proteins in dose- and time-dependent manner by RA FLS, but did not affect the expression of total ERM protein. Rho kinase and p38MAPK signal pathways were involved in TNF-α-induced ERM phosphorylation. We further showed that inhibition of ERM phosphorylation by siRNA-mediated ERM knockdown suppressed TNF-α- or IL-1β-induced BrdU incorporation and PCNA expression in RA FLS.

CONCLUSIONS

This study provides the novel evidence that increased phosphorylation of ERM proteins may contribute to proliferation of RA FLS, suggesting that specific inhibition of ERM phosphorylation may be a new therapeutic approach for RA.

[Cytokine in synovial monocytic cells from rheumatoid arthritis patients]

OBJECTIVE

To evaluate the inhibitory effect of blockade of Rho kinase upon mediating the secretion of proinflammatory cytokine in monocytic cells from rheumatoid arthritis (RA) patients.

METHODS

Synovial fluid (SF) monocytic cells and peripheral blood monocytes (PB) from active RA patients were treated with TNFalpha or LPS respectively in the presence or absence of a specific ROK inhibitor, Y27632. ROK activity was assessed by Western blot and cytokine secretion measured by ELISA.

RESULTS

Elevated ROK activity was found in synovial fluid monocytic cells from active RA patients. ROK activity was correlated with DAS, an index of disease activity of RA patients. ROK inhibitor Y27632 reduced the secretion of TNFalpha, IL-1beta and IL-6 in RA SF monocytic cells, but had no effect upon the secretion of IL-10, an anti-inflammatory cytokine.

CONCLUSION

The present study provides novel evidence that ROK mediates the secretion of proinflammatory cytokines in monocytic cells from RA synovial fluids, suggesting a critical role of ROK in macrophage-mediated synovial inflammation of RA. Thus inhibition of ROK may be a new therapeutic target for RA.

Antiinflammatory effect of Rho kinase blockade via inhibition of NF-kappaB activation in rheumatoid arthritis

OBJECTIVE

There is increasing evidence that the RhoA signaling pathway may play a critical role in the inflammatory response. This study was undertaken to examine the effects of RhoA and its downstream effector Rho kinase (ROK) in synovial inflammation in rheumatoid arthritis (RA).

METHODS

RhoA activity was assessed by pull-down assay. Fasudil and Y27632, both specific inhibitors of ROK, were used to examine the role of ROK in inflammatory responses in vivo and in vitro. Nuclear translocation of NF-kappaB was measured by confocal fluorescence microscopy, and DNA binding activity was assessed with a sensitive multiwell colorimetric assay. Enzyme-linked immunosorbent assay was used to detect cytokine production.

RESULTS

Increased activation of RhoA was found in inflamed synovial membrane cells isolated from patients with RA and from rats with collagen-induced arthritis (CIA). Intraperitoneal administration of fasudil in rats with CIA significantly reduced synovial inflammation and ROK activity. In vitro, treatment with fasudil or Y27632 decreased production of tumor necrosis factor alpha (TNFalpha), interleukin-1beta (IL-1beta), and IL-6 by synovial membrane cells, peripheral blood mononuclear cells, and fibroblast-like synoviocytes from patients with active RA. Inhibition of ROK by specific inhibitors or ROK small interfering RNA suppressed lipopolysaccharide- or TNFalpha-induced NF-kappaB nuclear translocation, DNA binding activity, luciferase reporter gene expression, and IkappaBalpha degradation.

CONCLUSION

The results of this study provide new evidence that blockade of ROK inhibits activation of NF-kappaB and production of proinflammatory cytokines, suggesting a critical role of ROK in the synovial inflammation of RA. Specific inhibition of ROK may be a novel therapeutic approach in RA.

Duration of feeding linseed diet influences expression of inflammation-related genes and growth performance of growing-finishing barrows

The aim of the study was to investigate the effects of dietary linseed (rich in n-3 PUFA) on expression of inflammation-related genes and on growth performance of growing-finishing barrows. Two isoenergetic and isonitrogenous diets were formulated, one as the basal diet and the other containing 10% linseed. Twenty-four Landrace x Yorkshire barrows weighing 35 +/- 3.7 kg were randomly assigned to 1 of 4 treatment groups, with 6 pigs per group. During the entire experimental period of 90 d, these 4 groups of pigs were first fed the basal diet and then fed the linseed diet for 0, 30, 60, and 90 d before slaughter, respectively. Pig growth; messenger RNA (mRNA) expression of peroxisome proliferator-activated receptor-gamma (PPARgamma), IL-1beta0, IL-6, and tumor necrosis factor-alpha (TNF-alpha); and plasma concentrations of the 3 proinflammatory cytokines were measured and analyzed. Average daily feed intake did not differ among treatment groups (P > 0.05), but ADG (P < 0.05) and G:F (P < 0.01) responded quadratically to the duration of linseed diet feeding, and pigs in the 60-d treatment group had the greatest ADG and G:F. The mRNA expression of PPARgamma in loin muscle and spleen increased linearly (P < 0.01) with the duration of linseed diet feeding, whereas its expression in adipose tissue was not affected (P = 0.095). Tumor necrosis factor-alpha and IL-6 mRNA expression in muscle, adipose, and spleen, as well as serum concentration of TNF-alpha, decreased linearly (P < 0.01) with the duration of linseed diet feeding. Peroxisome proliferator-activated receptor-gamma mRNA abundance was negatively correlated with IL-1beta, IL-6, and TNF-alpha mRNA abundance both in muscle (R(2) = 0.63, P < 0.001) and in spleen (R(2) = 0.69, P < 0.001), and PPARgamma mRNA expression in spleen (R(2) = 0.59, P < 0.01) and muscle (R(2) = 0.52, P < 0.05) was negatively correlated with serum TNF-alpha concentration. There were also significant quadratic relations between ADG and expression of PPARgamma (P < 0.05) and splenic TNF-alpha (P < 0.05). These data suggest that intake of n-3 PUFA from the linseed diet led to significant decreases in the expression of proinflammatory cytokine genes, which may stimulate growth in growing-finishing barrows, at least in part, through a PPARgamma-dependent mechanism.

[Clinical study of etanercept for treating ankylosing spondylitis]

OBJECTIVE

To evaluate the efficacy and safety of etanercept, a tumor necrosis factor (TNF)-alpha inhibitor, in the treatment of ankylosing spondylitis (AS), and investigate its effect on serum levels of matrix metalloproteinase-3 (MMP-3).

METHODS

Forty-eight patients with AS received etanercept 25 mg twice a week for a treatment course of 12 weeks. The patients' symptoms, signs, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) levels and side effects were observed before and after the treatment. The serum levels of MMP-3 was determined using enzyme-linked immunosorbent assay (ELISA).

RESULTS

All the patients completed the treatment. The degree of spinal pain and pain at night, the duration of morning stiffness, the finger-to-floor distance, BASDAI and BASFI were significantly improved after the treatment (P<0.05). Etanercept treatment resulted in a significant reduction in serum MMP-3 level in the AS patients to 31.22-/+10.26 ng/ml as compared with the level before treatment (46.17-/+25.74 ng/ml, P<0.05). The reduction of serum MMP-3 was positively correlated to decrement of ESR and CRP (r=0.397 and 0.474, respectively, P<0.05). The most common adverse events of etanercept included injection site reaction and upper respiratory infection.

CONCLUSION

Etanercept treatment has obvious therapeutic effects on AS without serious adverse effects. MMP-3 may be a potentially useful indicator to assess the effect of anti-TNF-alpha treatment in AS patients.

[Abnormal signaling activity of phosphatidylinositol 3-kinase pathway in peripheral blood T cells from patients with systemic lupus erythematosus]

OBJECTIVE

To investigate the activity of phosphatidylinositol 3-kinase (PI3K) signal pathway, a cytoplasmic signaling pathway known to play an important role in T cell activation, in peripheral blood T cells from systemic lupus erythematosus (SLE) patients.

METHODS

T cells were isolated from the peripheral blood samples of 28 SLE patients, 5 males and 23 females, with RosettSep T cell purification kit. PI3K activity was determined by immunoprecipitation and ELISA, and Western blotting was used to measure the Akt and phosphorylated Akt protein expression. T cell proliferation and cytokine production was examined by MTT test and ELISA respectively. Fifteen healthy adults and 8 active rheumatoid arthritis patients were used as controls. The T cells from the SLE patients and normal controls were treated with 10% normal control serum of SLE serum for 24 h ("rest") and then to detect the P13K and Akt activity. Some T cells from the SLE patients were stimulated with CD3/CD28 mono-antibodies or CD3/CD28 mono-antibodies + LY294002, a specific P13K inhibitor, and then the proliferation and secretion of IL-6 and IL-10 were analyzed.

RESULTS

Compared with the healthy controls and rheumatoid arthritis patients, the activity levels of PI3K and Akt in the T cells of peripheral blood from the SLE patients were significantly increased. T cells allowed to "rest" for 24 hours in culture medium showed a reversal of the changes in activity of PI3K and Akt. The activity of PI3K pathway was increased in the T cells from healthy controls when cultured with SLE serum. The proliferation and IL-6 and IL-10 secretion of the T cells from SLE patients cultured with LY294002 were inhibited. The P13K and Akt activity levels of the T cells from SLE patients were not related to SLE disease activity index (SLEDAI).

CONCLUSION

The T cells from SLE patients show an abnormal activation of PI3K pathway which may be due, at least in part, to their exposure to relevant serum factors.

[Role of gonadotropin releasing hormone analogues for ovarian protection in systemic lupus erythematosus patients treated with cyclophosphamide]

OBJECTIVE

To evaluate the effectiveness of gonadotropin releasing hormone analogues (GnRH-a) in protection against premature ovarian failure during cyclophosphamide (CTX) therapy for systemic lupus erythematosus (SLE).

METHODS

28 female patients with SLE, aged 35.3 +/- 2.4 (30-39) were treated with prednisone orally 1 mg/kg daily for 8 weeks, and then the dose was decreased by 10% every 10 days. CTX 200 mg with normal saline 200 ml was intravenously injection every other day for 4 months. Peripheral white blood cell (WBC) count was made every week. If the WBC count was less than 3.5 x 10(9)/L, the use of CTX should be stopped temporarily until the WBC count became normal. And then, the CTX administration should be adjusted to 400 mg intravenously every week. All patients were offered treatment with Hypodermic injection of GnRH-a 3.75 mg was given monthly just at the beginning of the standard CTX regimen for 3 months. Follow-up was conducted for 6 months after the last prescription of GnRH-a.

RESULTS

All patients developed amenorrhea after treated by GnRH-a. Menstruation recovered 73 days (69-82 days) after the last subcutaneous injection in 25 patients. Among these 25 patients, one developed amenorrhea again after two normal menses periods. The other 3 patients were in persistent amenorrhea during the following 6 months after the GnRH-a treatment. The levels of plasma estradiol (E2) was 998 +/- 308 pmol/L before GnRH-a treatment, and decreased significantly 1, 2, and 3 months after the last injection of GnRH-a (132 +/- 44 pmol/L, 88 +/- 37 pmol/L and 81 +/- 29 pmol/L respectively, all P < 0.05). The level of plasma E2 increased 2 months after the last injection of GnRH-a in the 25 patients with return of menses, and the level of plasma E2 returned to the normal baseline level after 6 months in 24 patients.

CONCLUSION

Treatment with GnRH-a during CTX therapy is associated with a significant reduction of premature ovarian failure in most women with SLE.