Zenshiro Tamaki

Serum Levels of Galectin-3: Possible Association with Fibrosis, Aberrant Angiogenesis, and Immune Activation in Patients with Systemic Sclerosis

Objective. Galectin-3 is a multifunctional protein implicated in a variety of biological processes including fibrosis, angiogenesis, and immune activation, all of which are associated with the development of systemic sclerosis (SSc). We investigated the clinical significance of serum galectin-3 levels in SSc. Methods. Serum galectin-3 levels were determined by a specific ELISA in 58 patients with SSc and 19 healthy controls. Results. Serum galectin-3 levels were significantly lower in patients with diffuse cutaneous SSc (dcSSc) than in controls (3.29 ± 3.27 ng/ml vs 4.91 ± 2.67 ng/ml, respectively; p < 0.05), while being comparable between limited cutaneous SSc (3.70 ± 2.39 ng/ml) and healthy controls. In dcSSc, serum galectin-3 levels significantly correlated with total skin score (r = 0.45, p < 0.05). Serum galectin-3 levels were significantly decreased in early dcSSc (disease duration < 1 year; 1.64 ± 1.74 ng/ml; p < 0.05), but not in mid-stage dcSSc (1 to 6 years; 3.22 ± 3.16 ng/ml) or late-stage dcSSc (> 6 years; 4.86 ± 4.10 ng/ml), compared with controls. Serum galectin-3 levels were higher in SSc patients with both digital ulcers (DU) and elevated right ventricular systolic pressure (RVSP) than in those without each symptom (DU: 5.44 ± 3.74 ng/ml vs 2.99 ± 2.36 ng/ml, p < 0.05; elevated RVSP: 4.44 ± 3.14 ng/ml vs 2.82 ± 2.64 ng/ml, p < 0.05). Conclusion. Galectin-3 may be related to the developmental process of skin sclerosis in dcSSc and of DU and pulmonary vascular involvements in total SSc.

Serum adiponectin levels inversely correlate with the activity of progressive skin sclerosis in patients with diffuse cutaneous systemic sclerosis

Backgrounds  Adiponectin has been demonstrated to be one of anti‐inflammatory and anti‐fibrotic factors, suggesting the potential of this cytokine to be involved in the developmental process of systemic sclerosis (SSc).

A possible contribution of endothelial CCN1 downregulation due to Fli1 deficiency to the development of digital ulcers in systemic sclerosis.

CCN1 is a pleiotropic molecule involved in angiogenesis and postnatal vasculogenesis, both of which are impaired in systemic sclerosis (SSc). To elucidate the potential role of CCN1 in the development of SSc, we investigated CCN1 expression in the lesional skin of SSc patients and SSc animal models and the clinical correlation of serum CCN1 levels. CCN1 expression was markedly decreased in dermal small blood vessels of SSc patients compared with those of healthy controls, while comparable between normal and SSc dermal fibroblasts. Transcription factor Fli1, whose deficiency due to epigenetic suppression is implicated in the pathogenesis of SSc, occupied the CCN1 promoter and gene silencing of Fli1 resulted in the reduction of CCN1 expression in human dermal microvascular endothelial cells. Consistently, CCN1 expression was suppressed uniformly and remarkably in dermal blood vessels of Fli1+/− mice and partially in those of endothelial cell‐specific Fli1 knockout mice. Furthermore, serum CCN1 levels were significantly decreased in SSc patients with previous and current history of digital ulcers as compared to those without. Collectively, these results suggest that endothelial CCN1 downregulation at least partially due to Fli1 deficiency may contribute to the development of digital ulcers in SSc patients. This study further supports the idea that epigenetic downregulation of Fli1 is a potential predisposing factor in the pathogenesis of SSc.

Effects of the immunosuppressant rapamycin on the expression of human α2(I) collagen and matrix metalloproteinase 1 genes in scleroderma dermal fibroblasts

BACKGROUND Rapamycin has been shown to exert an anti-fibrotic effect on skin fibrosis in a certain subset of patients with systemic sclerosis (SSc) and in bleomycin-treated animal models. OBJECTIVES To investigate the mechanism responsible for the anti-fibrotic effect of rapamycin especially by focusing on human α2(I) collagen (COL1A2) and matrix metalloproteinase 1 (MMP1) genes in normal and systemic sclerosis (SSc) dermal fibroblasts. METHODS The expression levels of type I procollagen and MMP1 proteins were analyzed by immunoblotting and the mRNA levels of COL1A2 and MMP1 genes were evaluated by quantitative real-time RT-PCR. The activities of COL1A2 and MMP1 promoters were determined by reporter analysis. RESULTS Rapamycin significantly decreased the levels of type I procollagen protein and COL1A2 mRNA, while significantly increasing the levels of MMP1 protein and mRNA in normal dermal fibroblasts. Similar effects of rapamycin were also observed in SSc dermal fibroblasts. Importantly, the inhibitory and stimulatory effects of rapamycin on the mRNA levels of COL1A2 and MMP1 genes, respectively, were significantly greater in SSc dermal fibroblasts than in normal dermal fibroblasts. In SSc dermal fibroblasts, rapamycin affected the expression of COL1A2 gene at the post-transcriptional level. In contrast, rapamycin altered the expression of MMP1 gene at the transcriptional level through the JNK/c-Jun signaling pathway in those cells. CONCLUSION Rapamycin has a potential to directly regulate the deposition of type I collagen in extracellular matrix through inhibiting type I collagen synthesis and promoting its degradation by MMP1, suggesting that this drug is useful for the treatment of SSc.

Effects of bosentan on nondigital ulcers in patients with systemic sclerosis

Background  Bosentan is an oral dual endothelin receptor antagonist, which has been shown to be efficacious for preventing new digital ulcers in patients with systemic sclerosis (SSc) in two high‐quality randomized controlled trials. However, its efficacy for nondigital ulcers in SSc remains unknown.

Successful experience of rituximab therapy for systemic sclerosis-associated interstitial lung disease with concomitant systemic lupus erythematosus.

Previous studies have demonstrated that B cells play critical roles in autoimmune disorders including systemic sclerosis (SSc) and systemic lupus erythematosus (SLE). However, the effectiveness of rituximab (RTX), a chimeric anti‐CD20 antibody, for SSc‐associated interstitial lung disease (ILD) or SLE disease activity remains controversial. We herein report an SSc patient with severely progressed ILD and concomitant SLE treated by two cycles of RTX at baseline and half a year later. This treatment improved ILD and SLE activities, along with reduction of dermal sclerosis and serum anti‐topoisomerase I antibody levels. In addition, our detailed time‐course data indicate that half a year may be appropriate as an interval between each cycle of RTX therapy aimed at SSc‐associated ILD or SLE. Overall, the current report could pave the way to establish RTX as a disease‐modifying drug for patients with SSc and/or SLE showing resistance to other already approved medications.

Association of anti-RNA polymerase III antibody and malignancy in Japanese patients with systemic sclerosis

Patients with systemic sclerosis (SSc) have an increased risk of malignancy compared with the general population. Recently, SSc patients with anti‐RNA polymerase III antibody have been reported to have an increased risk of malignancy as compared with those with other disease‐specific autoantibodies in US, European and Australian populations. Therefore, we studied the relationship between disease‐specific autoantibodies and malignancy in 261 Japanese SSc patients. The prevalence of malignancy was significantly higher in patients with anti‐RNA polymerase III antibody (7/22, 31.8%) than in those with anti‐topoisomerase I antibody (2/82, 2.4%) and in those with anticentromere antibody (8/137, 5.8%). Importantly, among seven patients with anti‐RNA polymerase III antibody and malignancy, three patients (42.9%) developed malignancy from 6 months before to 12 months after SSc onset. Thus, malignancy complication in Japanese SSc patients with anti‐RNA polymerase III antibody is as high as that in other races, suggesting that SSc patients with anti‐RNA polymerase III antibody share the same pathological process among different ethnic groups.

Clinical significance of serum decoy receptor 3 levels in patients with systemic sclerosis

Decoy receptor 3 (DcR3) is associated with autoimmunity and altered angiogenesis in certain pathological conditions. We herein measured serum DcR3 levels in 51 patients with systemic sclerosis (SSc) and 19 healthy controls and evaluated their clinical significance in this disorder. Serum DcR3 levels were significantly higher in diffuse cutaneous SSc (dcSSc) patients than in limited cutaneous SSc patients and in healthy controls. In dcSSc, serum DcR3 levels were significantly elevated in patients with disease duration of ≤6 years compared with healthy controls, but not in those with disease duration of >6 years. Serum DcR3 levels correlated negatively with the percentage of predicted diffusion lung capacity for carbon monoxide and positively with right ventricular systolic pressure. Furthermore, serum DcR3 levels positively correlated with C-reactive protein, erythrocyte sedimentation rate and immunoglobulin G. Collectively, the elevation of serum DcR3 levels is associated with the development of pulmonary arterial hypertension and systemic inflammation in SSc.

Improvement of endothelial function in parallel with the amelioration of dry cough and dyspnea due to interstitial pneumonia by intravenous cyclophosphamide pulse therapy in patients with systemic sclerosis : a preliminary report of two cases

Intravenous cyclophosphamide pulse therapy (IVCY) exerts its efficacy against interstitial lung disease (ILD) associated with systemic sclerosis (SSc) by restoring vascular injuries as well as aberrant immune activation. We recently experienced two patients with SSc-ILD in whom the values of brachial flow-mediated dilation (FMD) reflected the efficacy of IVCY. We herein report the details of these cases and discuss the potential of FMD to predict and evaluate the effect of IVCY on SSc-ILD.

Significant attenuation of macrovascular involvement by bosentan in a patient with diffuse cutaneous systemic sclerosis with multiple digital ulcers and gangrene

Systemic sclerosis (SSc) is characterized by vascular injuries, and bosentan has recently been proved to be efficacious for the prevention of new digital ulcers in SSc. We herein report a case of SSc in a patient with refractory digital ulcers and gangrene treated with bosentan. Stenosis of the ulnar artery, evaluated by magnetic resonance angiography, was attenuated by the bosentan treatment, suggesting that bosentan exerts a reverse remodeling effect against the pathological organic changes of arteries in SSc.