Possible association of decreased serum CXCL14 levels with digital ulcers in patients with systemic sclerosis

FLI-1-driven regulation of endothelial cells in human diseases

Endothelial cells (ECs) are widely distributed in the human body and play crucial roles in the circulatory and immune systems. ECs dysfunction contributes to the progression of various chronic cardiovascular, renal, and metabolic diseases. As a key transcription factor in ECs, FLI-1 is involved in the differentiation, migration, proliferation, angiogenesis and blood coagulation of ECs. Imbalanced FLI-1 expression in ECs can lead to various diseases. Low FLI-1 expression leads to systemic sclerosis by promoting fibrosis and vascular lesions, to pulmonary arterial hypertension by promoting a local inflammatory state and vascular lesions, and to tumour metastasis by promoting the EndMT process. High FLI-1 expression leads to lupus nephritis by promoting a local inflammatory state. Therefore, FLI-1 in ECs may be a good target for the treatment of the abovementioned diseases. This comprehensive review provides the first overview of FLI-1-mediated regulation of ECs processes, with a focus on its influence on the abovementioned diseases and existing FLI-1-targeted drugs. A better understanding of the role of FLI-1 in ECs may facilitate the design of more effective targeted therapies for clinical applications, particularly for tumour treatment.

Endothelial CCR6 expression due to FLI1 deficiency contributes to vasculopathy associated with systemic sclerosis

Background

We have recently demonstrated that serum CCL20 levels positively correlate with mean pulmonary arterial pressure in patients with systemic sclerosis (SSc). Considering a proangiogenic effect of CCL20 on endothelial cells via CCR6, the CCL20/CCR6 axis may contribute to the development of SSc vasculopathy. Therefore, we explored this hypothesis using clinical samples, cultured cells, and murine SSc models.

Methods

The expression levels of CCL20 and CCR6 in the skin, mRNA levels of target genes, and the binding of transcription factor FLI1 to the target gene promoter were evaluated by immunostaining, quantitative reverse transcription PCR, and chromatin immunoprecipitation, respectively. Vascular permeability was evaluated by Evans blue dye injection in bleomycin-treated mice. Angiogenic activity of endothelial cells was assessed by in vitro angiogenesis assay.

Results

CCL20 expression was significantly elevated in dermal fibroblasts of patients with early diffuse cutaneous SSc, while CCR6 was significantly up-regulated in dermal small vessels of SSc patients irrespective of disease subtypes and disease duration. In human dermal microvascular endothelial cells, FLI1 siRNA induced the expression of CCR6, but not CCL20, and FLI1 bound to the CCR6 promoter. Importantly, vascular permeability, a representative SSc-like vascular feature of bleomycin-treated mice, was attenuated by Ccr6 siRNA treatment, and CCR6 siRNA suppressed the angiogenic activity of human dermal microvascular endothelial cells assayed by in vitro tube formation.

Conclusions

The increased expression of endothelial CCR6 due to FLI1 deficiency may contribute to the development of SSc vasculopathy.

Decidual IDO+ macrophage promotes the proliferation and restricts the apoptosis of trophoblasts

Indoleamine 2, 3-dioxygenase (IDO), a tryptophan-catabolizing enzyme, is essential in physiological immunoregulation. The present research was conducted to elucidate the expression and roles of IDO in decidual macrophages (dMφ) during early pregnancy. Here, we observed a remarkable decrease of IDO⁺ dMφ from patients with unexplained recurrent spontaneous abortion (URSA). IDO⁺ dMφ displayed M2 phenotype with higher CD206, CD209 and CD163, and lower CD86. Interestingly, treatment with 1-methyl-d-tryptophan (1-MT, an IDO pathway inhibitor) led to the M1 bias of dMφ. Further analysis of the cytokine array and the qPCR showed decreased levels of trophoblast proliferation or invasion-related molecules (e.g., CXCL12 and BMP2) in 1-MT-treated dMφ. The data of co-culture system showed that 1-MT-pretreated dMφ decreased the proliferation and the expression of Ki-67 and Bcl-2, and increased cell apoptosis of HTR-8/Snveo cells. Additionally, the expression of IDO in U937 cells was up-regulated by decidual stromal cells (DSC) and HTR-8/Snveo cells in vitro, as well as estradiol and medroxyprogesterone. These data suggest that endocrine environment, DSC and trophoblasts should contribute to the high level of IDO in dMφ, and IDO⁺ dMφ with M2 dominant phenotype promote the survival of trophoblasts during early pregnancy. The abnormal lower level of IDO should trigger the dysfunction of dMφ, further suppress the survival of trophoblasts and increase the risk of miscarriage.

Serum C-X-C motif chemokine ligand 14 levels are associated with serum C-peptide and fatty liver index in type 2 diabetes mellitus patients

AIMS/INTRODUCTION

Recent studies have suggested C-X-C motif chemokine ligand 14 (CXCL14), secreted from adipose tissue, to play an important role in the pathogenesis of metabolic syndrome. However, the clinical significance of CXCL14 in humans has not been elucidated. This study aimed to assess correlations between serum CXCL14 levels and clinical parameters in patients with type 2 diabetes mellitus.

MATERIALS AND METHODS

In total, 176 individuals with type 2 diabetes mellitus were recruited. Serum CXCL14 concentrations were determined by enzyme-linked immunosorbent assay. We examined the associations of serum CXCL14 levels with laboratory values, abdominal computed tomography image information, surrogate markers used for evaluating the pathological states of diabetes, obesity and atherosclerosis.

RESULTS

Serum CXCL14 levels correlated positively with body mass index, waist circumference, subcutaneous and visceral fat areas, and serum alanine transaminase, uric acid, total cholesterol, low-density lipoprotein cholesterol, triglycerides and C-peptide (CPR) levels. In contrast, CXCL14 levels correlated inversely with age, pulse wave velocity and serum adiponectin levels. Multiple linear regression analysis showed serum levels of CPR (β = 0.227, P = 0.038) and the fatty liver index (β = 0.205, P = 0.049) to be the only parameters showing independent statistically significant associations with serum CXCL14 levels.

CONCLUSIONS

Serum CXCL14 levels were independently associated with serum CPR and fatty liver index in patients with type 2 diabetes mellitus. In these patients, a high serum CPR concentration might reflect insulin resistance rather than β-cell function, because CXCL14 showed simple correlations with obesity-related parameters. Collectively, these data suggested that serum CXCL14 levels in type 2 diabetes patients might be useful predictors of elevated serum CPR and hepatic steatosis.