Xiao-Mei Li

Emerging role of long noncoding RNAs in autoimmune diseases.

Long noncoding RNA (lncRNA), with size larger than 200 nucleotides, is a new class of noncoding RNA. Emerging evidence has revealed that lncRNAs play a key role in the regulation of immunological functions and autoimmunity. Herein, we review the recent findings of lncRNA regulation in immune functions and in the development of autoimmunity and autoimmune disease. In addition, we focus on the involvement of lncRNA regulation in innate and adaptive immune responses, immune cell development, and differential expression of lncRNAs in autoimmune diseases, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), type 1 diabetes mellitus (T1DM), multiple sclerosis (MS), autoimmune thyroid disease (AITD), psoriasis, polymyositis/dermatomyositis (PM/DM) and Crohns disease (CD).

Subclinical atherosclerosis in patients with systemic lupus erythematosus: A systemic review and meta-analysis

OBJECTIVEnSystemic lupus erythematosus (SLE) is associated with increased risk of cardiovascular disease. Carotid intima media thickness (CIMT) and carotid plaques are both frequently used to identify populations at higher cardiovascular risk. A systematic literature search and meta-analysis were performed to evaluate CIMT and carotid plaques difference between SLE patients and normal controls.nnnMETHODSnThe literatures comparing markers of cardiovascular risk (CIMT and prevalence of carotid plaques) in SLE and controls were systematically searched in PubMed, EMBASE and Cochrane databases. The overall mean CIMT difference and pooled odds ratio (OR) for the prevalence of carotid plaques between SLE patients and control groups were calculated by fixed-effects or random-effect model analysis. Meta-regression was performed to explore the potential influencing factors. Publication bias was examined by a funnel plot and Eggers test.nnnRESULTSnA total of 80 studies (6085 SLE patients and 4794 controls) were included in the final analysis, 71 studies with data on CIMT (4814 cases and 3773 controls) and 44 studies reporting on the prevalence of carotid plaques (4417 cases and 3528 controls). As compared to controls, SLE patients showed a higher CIMT (WMD: 0.07 mm; 95%CI: 0.06, 0.09; P<0.001), and an increased prevalence of carotid plaques (OR: 2.45; 95%CI: 2.02, 2.97; P<0.001). Meta-regression models showed that traditional cardiovascular risk factors (age, HDL and triglyceride of SLE patients) and lupus related risk factors (as expressed by duration, ESR, SLEDAI and steroids) had a significant influence on CIMT, steroids and triglyceride had significant influence on the prevalence of carotid plaques.nnnCONCLUSIONSnOur findings support the current evidence base for an increased cardiovascular burden in SLE patients and support the use of CIMT and carotid plaques in observational studies in SLE patients. The findings are of importance to design more specific prevention and treatment strategies.

Plasma/Serum Leptin Levels in Patients with Systemic Lupus Erythematosus: A Meta-analysis.

BACKGROUND AND AIMSnCurrently published data regarding the relationship between plasma/serum leptin levels and systemic lupus erythematosus (SLE) are contradictory. To derive a more precise evaluation of this relationship, a meta-analysis was performed.nnnMETHODSnPublished literature from PubMed, Embase and Cochrane Library were obtained. The study quality was assessed by the Newcastle-Ottawa scale. Pooled standard mean difference (SMD) with 95% confidence interval (CI) was calculated by fixed-effects or random-effect model analysis. Heterogeneity among studies was estimated using the Cochran Q and I(2) statistics.nnnRESULTSnA total of 11 studies including 868 SLE patients and 591 controls were finally included in the meta-analysis. No significant differences in plasma/serum leptin levels was found between SLE patients and healthy controls when all studies were pooled into the meta-analysis (pooled SMD = 0.269, 95% CI = -0.188 to 0.726). However, subgroup analyses showed that SLE patients from an Asian population, age ≥40 years and BMI <25 had higher plasma/serum leptin levels when compared with controls.nnnCONCLUSIONnThere is no significant difference in plasma/serum leptin levels between the entire group of SLE patients and controls. However, plasma/serum leptin levels are significantly higher in the subgroup of SLE patients from an Asian population ≥40 years of age and with a BMI <25.

Identification of long non-coding RNAs GAS5, linc0597 and lnc-DC in plasma as novel biomarkers for systemic lupus erythematosus.

Despite increasing evidence that long non-coding RNAs (lncRNAs) widely take part in human diseases, the role of lncRNAs in systemic lupus erythematosus (SLE) is largely unknown. In this study, we performed a two-stage study to explore the plasma levels of five lncRNAs (GAS5, linc0949, linc0597, HOTAIRM1 and lnc-DC) and their potential as SLE biomarkers. Compared with healthy controls, plasma levels of GAS5 and lnc-DC were significantly decreased (P < 0.001 and P = 0.002, respectively) while linc0597 were overexpressed in SLE patients (P < 0.001). When SLE patients were divided into SLE without nephritis and lupus nephritis (LN), the levels of lnc-DC were significantly higher in LN compared with SLE without nephritis (P = 0.018), but no significant difference in levels of GAS5 and linc0597 were found between LN and SLE without nephritis; plasma linc0949 level showed no significant difference in all comparisons. Further evaluation on potential biomarkers showed that GAS5, linc0597 and lnc-DC may specifically identify patients with SLE, the combination of GAS5 and linc0597 provided better diagnostic accuracy; lnc-DC may discriminate LN from SLE without nephritis. In summary, GAS5, linc0597 and lnc-DC in plasma could be potential biomarkers for SLE.

Emerging role of adipokines in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder characterized by multisystem organ involvement and unclear pathogenesis. Several adipokines synthesized in the adipose tissue, including leptin, adiponectin, resistin, and chemerin, have been explored in autoimmune rheumatic diseases, especially SLE, and results suggest that these mediators may be implicated in the pathogenesis of SLE. However, the current results are controversial. In this review, we will briefly discuss the expression and possible pathogenic role of several important adipokines, including leptin, adiponectin, resistin, and chemerin in SLE.

Expression of Ets-1 and FOXP3 mRNA in CD4(+)CD25 (+) T regulatory cells from patients with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with complex genetic predisposing factors involved. Ets-1 transcription factor plays an important role in the suppressive activity of CD4+CD25+ Treg cells and stable expression of FOXP3. To find its potential role in the pathogenesis of SLE, we investigate the mRNA expression of Ets-1 and FOXP3 mRNA in CD4+CD25+ Treg cells from patients with SLE. Real-time transcription-polymerase chain reaction analysis was used to determine the expression of Ets-1 and FOXP3 mRNA in CD4+CD25+ Treg cells from 36 patients with SLE and 18 sex-and-age-matched healthy controls. The Ets-1 mRNA expression level was decreased in patients with SLE [0.225 (0.135, 0.337)] than healthy controls [0.528 (0.303, 0.681)] (Pxa0<xa00.001). The expression levels of FOXP3 mRNA were lower in SLE patients [0.608 (0.272, 1.164)] than healthy controls [0.919 (0.690, 1.223)], but the difference was not significant (Pxa0=xa00.106). Significant reduction in Ets-1 and FOXP3 expression was also found in new-onset SLE subgroup when compared with healthy controls (Pxa0<xa00.001). The level of Ets-1 and FOXP3 mRNA was not significantly different in hyperactive and lower active SLE group when compared with inactive SLE group, respectively (Pxa0>xa00.05). There were no significant differences between SLE with lupus nephritis (LN) and SLE without LN either (Pxa0>xa00.05). Associations of Ets-1 and FOXP3 mRNA expression levels with major clinical and laboratory parameters of SLE patients were also analyzed. However, no significant association was found. Significant positive correlation was found between Ets-1 and FOXP3 mRNA expression in CD4+CD25+ Treg cells from SLE patients (rxa0=xa00.698, Pxa0<xa00.001). Our results found that the expression levels of Ets-1 mRNA were decreased in SLE patients and Ets-1 expression was positively correlated with the expression of FOXP3. It indicated that Ets-1 may play an important role in the stable expression of FOXP3 in CD4+CD25+ Treg cells.

Plasma levels of adipokines in systemic lupus erythematosus patients

OBJECTIVEnTo evaluate the plasma levels of six adipokines, including chemerin, omentin-1, lipocalin-2, cathepsin-S, cathepsin-L and adipsin, in patients with SLE.nnnMETHODSnNinety SLE patients and ninety control subjects were recruited, plasma adipokines levels were measured by enzyme-linked immunosorbent assay, and their associations with major clinical and laboratory indexes were analyzed.nnnRESULTSnThere were no significant differences in plasma chemerin, omentin-1, lipocalin-2, cathepsin-S, cathepsin-L and adipsin levels between SLE patients and controls. Further subgroup analyses by major clinical and laboratory indexes showed that plasma omentin-1 level was significantly lower in SLE patients without nephritis when compared with those patients with nephritis (P=0.002). Plasma chemerin, cathepsin-S levels in SLE patients without nervous system disorder were significantly lower in comparison with SLE patients with nervous system disorder (P=0.035, P=0.029). No significant associations of other adipokines with any major clinical and laboratory indexes were observed.nnnCONCLUSIONSnPlasma levels of chemerin, omentin-1, lipocalin-2, cathepsin-S, cathepsin-L and adipsin in SLE patients were not markedly different from the normal controls. The presence of nephritis was connected with higher plasma omentin-1 levels in SLE patients, and the presence of nervous system disorder was associated with higher plasma chemerin, cathepsin-S levels in SLE patients. However, functional studies are awaited to further explore the potential roles of these cytokines in SLE.

Evidence for genetic association of TBX21 and IFNG with systemic lupus erythematosus in a Chinese Han population

TBX21 recode T-bet which is an important transcription factor that drives the Th1 immune response primarily by promoting expression of the interferon-gamma (IFNG) gene. Recent studies have shown that genetic variants in TBX21 and IFNG are connected with risk of systemic lupus erythematosus (SLE). The aim of the present study was to replicate these genetic associations with SLE in Anhui Chinese population. Genotyping of 3 variants (rs4794067 in TBX21, rs2069705 and rs2069718 in IFNG) was performed. A total of 3732 subjects were included in the final analysis. The study only identified the association of rs2069705 with SLE susceptibility (T vs. C: odds ratio [OR]u2009=u20091.12, 95% confidence interval [CI]u2009=u20091.00–1.26, Pu2009=u20090.046). Combined analysis with Hong Kong GWAS showed that the OR for rs2069705 was 1.10 (95% CI: 1.01–1.21, Pu2009=u20090.027). Further pooled analysis with Korean populations involving 10498 subjects showed a more significant association between rs2069705 and SLE (T vs. C: ORu2009=u20091.11, 95%CIu2009=u20091.04–1.19, Pu2009=u20090.002; TTu2009+u2009TC vs. CC: ORu2009=u20091.11, 95%CIu2009=u20091.02–1.21, Pu2009=u20090.012; TT vs. TCu2009+u2009CC: ORu2009=u20091.28, 95%CIu2009=u20091.07–1.54, Pu2009=u20090.008; TT vs. CC: ORu2009=u20091.33, 95%CIu2009=u20091.10–1.60, Pu2009=u20090.003). In addition, we also identified a significant genetic interaction between rs2069705 and rs4794067 in Anhui Chinese population. Our study suggests that IFNG and IFNG-TBX21 interaction are involved in SLE susceptibility.

NLRP3: A promising therapeutic target for autoimmune diseases

NLRP3, a member of nucleotide-binding domain-(NOD) like receptor family, can be found in large varieties of immune and non-immune cells. Upon activation, the NLRP3, apoptosis-associated speck-like protein (ASC) and pro-caspase-1 would assemble into a multimeric protein, called the NLRP3 inflammasome. Then the inflammasome promotes inflammation (through specific cleavage and production of bioactive IL-1β and IL-18) and pyroptotic cell death. Previous studies have indicated the importance of NLRP3 in regulating innate immunity. Recently, numerous studies have revealed their significance in autoimmune diseases, such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc) and inflammatory bowel disease (IBD). In this review, we will briefly discuss the biological features of NLRP3 and summarize the recent progression of the involvement of NLRP3 in the development and pathogenesis of autoimmune diseases, as well as its clinical implications and therapeutic potential.

Increased Pulse Wave Velocity in Systemic Lupus Erythematosus: A Meta-Analysis

Systemic lupus erythematosus (SLE) is associated with increased cardiovascular risk. This study aims to derive a more precise estimation on pulse wave velocity (PWV) level in patients with SLE and related factors. A literature search was performed using PubMed, EMBASE, and The Cochrane Library databases, studies published up to February 28, 2017, in English. Pooled standardized mean difference (SMD) with 95% confidence interval (CI) was calculated by fixed-effect or random-effect model analysis. Heterogeneity test was performed by the Q statistic and quantified using I2 ; publication bias was evaluated using a funnel plot and Egger’s linear regression test. Of 156 studies found, 27 met eligibility criteria, and 14 studies were finally included in the meta-analysis. Meta-analysis revealed that the SLE group had significantly higher PWV levels than the control group; SMD = 0.56 and 95% CI (0.30-0.82). Subgroup analyses showed that body mass index (BMI), sample size, and disease duration were associated with PWV in patients with SLE. Overall, our study suggests that patients with SLE have a higher PWV level, and it is associated with BMI, sample size, and disease duration.