Increased expression of suppressor of cytokine signaling 1 mRNA in patients with rheumatoid arthritis

Inhibition of pSTAT1 by tofacitinib accounts for the early improvement of experimental chronic synovitis

Background

In order to gain insight into the early effects drawn by JAK inhibitors on intra-joint JAK/STAT-dependent signaling, we sought synovial activation of STATs and their end-products, along with their modification with tofacitinib (TOFA), at flare-up in antigen induced arthritis (AIA). New Zealand rabbits were randomly assigned to four groups –healthy controls, AIA, TOFA-treated AIA, or TOFA-treated controls–. AIA was induced with 4 weekly intra-articular ovalbumin injections in sensitized animals. TOFA (10 mg·kg^− 1·day^− 1) was administered for the last 2 weeks. Animals were euthanized 24 h after the last injection.

Results

AIA animals showed high-grade synovitis, which was partially improved by TOFA. No effects of the treatment were found on serum C-reactive protein or on the synovial macrophage infiltration at this stage. Synovial MMP-1,-3 and -13 expression levels in treated AIA rabbits were found to drop to those of controls, while a downregulation of IL6, IFNγ and TNF was evident in treated versus untreated AIA rabbits. Concurrently, a reduction in pSTAT1 and SOCS1, but not in pSTAT3, SOCS3 or active NFκB-p65, was noted with TOFA.

Conclusions

Studying the mechanism of action of immunomodulatory drugs represents a major challenge in vivo, since drug-dependent decreases in inflammation very likely mask direct effects on disease mechanisms. This study design allowed us to prevent any confounding effect resulting from reductions in the overall inflammatory status, hence assessing the true pharmacological actions of TOFA in a very severe synovitis. Our findings point to pSTAT1 and MMPs as early molecular readouts of response to this JAK inhibitor.

Electronic supplementary material

The online version of this article (10.1186/s12950-019-0206-2) contains supplementary material, which is available to authorized users.

Cytokine signal suppressor (SOCS) 1-1478 CA/del gene polymorphism in Turkish patients with polycystic ovary syndrome

Eighty-four subjects, premenopausal female patients (n = 42, mean (SD) age: 26.4 (4.2) years) diagnosed with polycystic ovary syndrome (PCOS) and age-matched healthy volunteers (n = 42, mean (SD) age: 27.6(3.4) years), were included in this study. Data on physical examination, anthropometric measurements and blood biochemistry analysis were recorded for each subject along with analysis for SOCS1-1478 CA/del polymorphism by polymerase chain reaction-restriction fragment length polymorphism. The relation of SOCS1-1478 CA/del polymorphism to PCOS status and insulin resistance was analysed via logistic regression analysis. Mean (SD) levels for BMI (28.5(6.5) vs.22.5 (4.9) kg/m², p < .001), HOMA-IR (3.1(1.8) vs.1.5 (1.0), p < .001), LDL-cholesterol (115.9(32.7) vs.100.7 (27.3)mg/dL, p = .03) and triglyceride (113.8(64.9) vs.83.3(36.3)mg/dL, p = .017) were significantly higher in patients. Groups were similar in terms of SOCS1-1478 CA/del polymorphism. No significant relation of this polymorphism was noted to PCOS and HOMA-IR. Our findings revealed no difference between groups in terms of the rate of SOCS1-1478 CA/del polymorphism, and no significant relation of this polymorphism to insulin resistance and PCOS status. Impact statement Polycystic ovary syndrome (PCOS), the most common cause of anovulation and the most commonly encountered form of female endocrine disease. SOCS proteins have been suggested to play a fundamental role in the negative feedback regulation of the JAK-STAT pathway, which is the major signalling pathway involved in a wide range of physiologic and pathologic processes, including inflammatory diseases, malignancies and immune disorders. Pathways involving the induction of suppression of SOCS proteins were also shown likely to be involved in mediating cytokine-induced insulin resistance. The present study was designed to determine the frequency of SOCS1-1478 CA/del gene polymorphism in patients with PCOS in relation to healthy controls and insulin resistance. Our findings revealed significantly higher rates of insulin resistance, obesity and dyslipidaemia in Turkish patients with PCOS compared with age-matched healthy controls, while no difference between study groups in terms of the rate of SOCS1-1478 CA/del polymorphism along with no significant relation of SOCS1-1478 CA/del polymorphism to insulin resistance and PCOS status. Future larger scale studies with the application of standardised diagnostic methods and criteria, and of state-of-the-art modern techniques including genomics, proteomics and pharmacogenetics would provide better understanding of the association between PCOS and genomic variants.

Evaluation of antigen-induced synovitis in a porcine model: Immunological, arthroscopic and kinetic studies

Background

Synovitis is an inflammation-related disease linked to rheumatoid arthritis, osteoarthritis, infections and trauma. This inflammation is accompanied by immune cells infiltration which initiates an inflammatory response causing pain, discomfort and affecting the normal joint function. The treatment of synovitis is based on the administration of anti-inflammatory drugs or biological agents such as platelet rich plasma and mesenchymal stem cells. However, the evaluation and validation of more effective therapies of synovitis requires the establishment of clinically relevant animal models.

Results

In this study, Large White pigs were pre-immunized to evaluate an antigen-induced synovitis. The immune monitoring of synovial fluids in this model allowed us the identification of IL-12p40 and T cell subsets as immune biomarkers. Moreover, the evolution of synovitis was performed by arthroscopic procedures and kinetic analysis. In summary, this paper describes an animal model of antigen-induced synovitis to be used in the evaluation of anti-inflammatory therapies.

Conclusions

The novelty of this paper lies in the development of a clinically relevant model of synovitis which permits the simultaneous evaluation of synovitis from an immunological, surgical and kinetic point of view.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-017-1025-4) contains supplementary material, which is available to authorized users.

Decreased SOCS1 mRNA expression levels in peripheral blood mononuclear cells from patients with systemic lupus erythematosus in a Chinese population

The aim of this study was to investigate the mRNA expression levels of suppressor of cytokine signaling 1 (SOCS1) in patients with systemic lupus erythematosus (SLE) compared with healthy controls. The associations of systemic lupus erythematosus disease activity index scores and clinical features of SLE with the expression levels of SOCS1 mRNA were also evaluated. Real-time quantitative reverse transcription-polymerase chain reaction was applied to detect the mRNA expression levels of SOCS1 in peripheral blood mononuclear cells from 34 patients with SLE and 34 healthy controls. The mRNA expression level of SOCS1 was significantly decreased in SLE patients in comparison with healthy controls (Z = -4.207, P < 0.001). Lower SOCS1 mRNA expression was detected in active SLE patients when compared with inactive ones (Z = -2.428, P = 0.015). There was no significant difference found for the SOCS1 mRNA levels between SLE patients with nephritis and those without (Z = -0.642, P = 0.521). The presence of photosensitivity, proteinuria, positive antinuclear antibody, and C4 decline were associated with SOCS1 mRNA levels in SLE patients (all P < 0.05). Furthermore, the SOCS1 mRNA expression was negatively correlated with disease activity (r s  = -0.372, P = 0.030). Our results suggest that the dysregulation of SOCS1 might be associated with the pathogenesis of SLE.

The SOCS-1 -1478CA/del polymorphism is not associated with colorectal cancer or age at onset in Turkish subjects

BACKGROUND

Suppressor of cytokine signaling (SOCS)-1 acts as a key regulator of many cytokine signaling pathways and its abnormal expression has been identified in several human malignancies, suggesting potential roles in carcinogenesis. The aim of this study was to investigate any association between the functional SOCS- 1 -1478CA>del polymorphism and colorectal cancer (CC) as well as age at onset in a Turkish clinical sample.

MATERIALS AND METHODS

A total of 122 subjects were enrolled in this case-control study (70 CC cases and 52 controls). The SOCS-1 -1478CA>del polymorphism was genotyped using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

The odds ratio of the del allele for CC relative to the CA allele was not significantly different between the groups (OR=0.71, 95% CI=0.41-1.22, p=0.27). This result did not change after adjustment for age and sex on multivariable regression analysis (OR=0.84, 95% CI=0.59-1.34, p=0.53). When the SOCS-1 -1478CA>del polymorphism was analyzed among CC patients in relation to the age at disease onset, we found no significant differences between subjects with the del/del, CA/del, and CA/CA genotypes.

CONCLUSIONS

The results of our study did not point towards a major role of the SOCS-1 -1478CA>del polymorphism in the pathogenesis of CC in Turkish subjects.

Regulation of CD4+ T-cell polarization by suppressor of cytokine signalling proteins

Suppressors of cytokine signalling (SOCS) proteins are induced in responses to many stimuli and by binding to cytokine receptors and associated janus kinase (JAK) proteins, directly regulate the activation of the signal transducers and activators of transcription (STATs). STAT proteins regulate the expression of many genes required for the differentiation of various CD4(+) T helper cell lineages, and there is now accumulating evidence that SOCS also play essential roles in the regulation and maintenance of CD4(+) T-cell polarization. As it is now clear that CD4(+) T cells are more plastic than initially thought, it is of particular importance to understand the molecular mechanisms regulating CD4(+) T-cell differentiation. Here we review the current understanding of how STATs and SOCS act in concert to influence the polarization of CD4(+) T cells and highlight the relevance of this in disease.