Elevation of plasma interleukin-18 concentration is associated with insulin levels in patients with systemic lupus erythematosus

Higher levels of IL-18 in patients with prediabetes compared to obese normoglycaemic controls

Background: Overweight and obesity are linked to low-grade chronic inflammation that can impair normal insulin function and induce insulin resistance. The aim of this study was to compare IL-18 levels between patients with prediabetes and obese normoglycaemic controls.Patients and methods: In this study, we included 131 patients with mean age 54.9 ± 9.1 years, divided into two groups - group 1 with obesity without glycaemic disturbances (n = 66) and group 2 with prediabetes (n = 65). IL-18 was measured using enzyme-linked immunosorbent assay (ELISA) method.Results: Patients with prediabetes had significantly higher levels of IL-18 compared to obese controls (304.0 ± 220.4 vs. 233.6 ± 103.6 pg/l, p=.029). When patients with prediabetes were divided into IFG only, IGT only and IFG + IGT the highest levels of IL-18 were found in IGT only patients.Conclusions: Patients with prediabetes have higher levels of IL18 compared to obese normoglycemic controls.

Autoimmune-mediated glucose intolerance in a mouse model of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of autoantibodies against self-antigens such as double-stranded DNA and phospholipids. Classical comorbidities of SLE include glomerulonephritis, infection, cardiovascular disease, arthritis, skin disorders, and neurological disease. In addition to these classical comorbidities, there is emerging evidence that SLE patients are at higher risk of developing insulin resistance and other components of the metabolic syndrome. Visceral adipose tissue inflammation is a central mediator of insulin resistance in the obese setting, but the mechanism behind the pathogenesis of metabolic disease in the SLE patient population is unclear. We hypothesize that lupus-associated changes in the adaptive immune system are associated with disruption in glucose homeostasis in the context of SLE. To test this hypothesis, we assessed the metabolic and immunological phenotype of SLE-prone B6.SLE mice. B6.SLE mice fed a low-fat diet had significantly worsened glucose tolerance, increased adipose tissue insulin resistance, increased β-cell insulin secretion, and increased adipocyte size compared with their respective B6 controls. Independently of diet, B cells isolated from the white adipose tissue of B6.SLE mice were skewed toward IgG production, and the level of IgG1 was elevated in the serum of SLE-prone mice. These data show that B6.SLE mice develop defects in glucose homeostasis even when fed a low-fat diet and suggest that B cells may play a role in this metabolic dysfunction.

Effects of aerobic exercise and whole body vibration on glycaemia control in type 2 diabetic males

Purpose

aerobic exercise has been identified as the main treatment for type 2 diabetic patients. Such an exercise, however, is usually repined by some of patients who suffer from lack of stamina. Therefore, whole body vibration has recently been introduced as a passive intervention. The present study aimed at comparing how aerobic exercise and whole body vibration affect glycaemia control in type 2 diabetic males.

Methods

Thirty diabetic males were divided into three groups, namely aerobic exercise (AE), whole body vibration (WBV), and control. Aerobic exercise schedule consisted of three walking sessions a week, each for 30-60 minutes and in 60-70% of maximum stock heartbeat. Vibration exercise was composed of 8-12-min stand-up and semi-squat positioning in frequency of 30 Hz and amplitude of 2 mm. Concentrations of fasting glycosylated hemoglobin, fasting glucose, and insulin were measured in the beginning of the trial, after the fourth week, and after the eighth week.

Results

After 8 weeks of exercise, no significant difference was detected in concentrations of fasting glycosylated hemoglobin and insulin between the groups (P=0.83, P=0.12). There were no significant differences in any of the variables between AE and WBV (P>0.05). But a more significant decrease in fasting glucose was observed in exercise groups (AE and WBV) compared with control group (P=0.02).

Conclusion

The present study showed that AE and WBV identically stimulate metabolic system. Thus, it can be concluded that type 2 diabetic patients lacking stamina for aerobic exercise can opt for vibration exercise as an effective substitute.

Clinical associations of the metabolic syndrome in systemic lupus erythematosus: data from an international inception cohort

BACKGROUND

The metabolic syndrome (MetS) may contribute to increased cardiovascular risk in systemic lupus erythematosus (SLE). We aimed to examine the association of demographic factors, lupus phenotype and therapy exposure with the presence of MetS.

METHODS

The Systemic Lupus International Collaborating Clinics Registry for Atherosclerosis inception cohort enrolled recently diagnosed (<15 months) SLE patients from 30 centres across 11 countries from 2000. Clinical, laboratory and therapeutic data were collected according to a standardised protocol. MetS was defined according to the 2009 consensus statement from the International Diabetes Federation. Univariate and backward stepwise multivariate logistic regression were used to assess the relationship of individual variables with MetS.

RESULTS

We studied 1686 patients, of whom 1494 (86.6%) had sufficient data to determine their MetS status. The mean (SD) age at enrolment and disease duration was 35.2 years (13.4) and 24.1 weeks (18.0), respectively. MetS was present at the enrolment visit in 239 (16%). In backward stepwise multivariable regression analysis, higher daily average prednisolone dose (mg) (OR 1.02, 95% CI 1.00 to 1.03), older age (years) (OR 1.04, 95% CI 1.03 to 1.06), Korean (OR 6.33, 95% CI 3.68 to 10.86) and Hispanic (OR 6.2, 95% CI 3.78 to 10.12) ethnicity, current renal disease (OR 1.79, 95% CI 1.14 to 2.80) and immunosuppressant use (OR 1.81, 95% CI 1.18 to 2.78) were associated with MetS.

CONCLUSIONS

Renal lupus, higher corticosteroid doses, Korean and Hispanic ethnicity are associated with MetS in SLE patients. Balancing disease control and minimising corticosteroid exposure should therefore be at the forefront of personalised treatment decisions in SLE patients.

Expressions of IL-18 and its binding protein in peripheral blood leukocytes and kidney tissues of lupus nephritis patients

To investigate the expressions of IL-18 and its binding protein (IL-18BP) in peripheral blood leukocytes and kidney tissues in patients with lupus nephritis (LN). SYBR-green-dye-I-based real-time quantitative PCR method was used to compare the gene expression levels (indicated as 2(-DeltaDeltaCT) value) of IL-18 and IL-18BP in the peripheral blood leucocytes of LN patients and those in normal controls. Serum levels of IL-18 were measured with ELISA method. Immunohistochemical evaluation of IL-18 and Il-18BP expression in LN was carried out on frozen renal biopsy sections. IL-18BP mRNA expression levels in LN patients were significantly lower than those of normal controls (P < 0.01). Serum levels of IL-18 in LN patients were significantly higher than those of normal controls (P < 0.01). It is noticeable that serum IL-18 levels in the patients treated with glucocorticoids and cyclophosphamide was lower than those treated with glucocorticoids only or glucocorticoids and other immune inhibitors such as chloroquine/hydroxychloroquine and azathioprine. Expression of IL-18 in renal glomeruli was higher in type-IV and type-V LN patients than in type-III LN patients. LN patients present lower IL-18BP mRNA expression and higher serum levels of IL-18 than those in normal controls. The preponderance of IL-18 in glomeruli from LN patients indicates IL-18 may be concerned with the local inflammation. Up-regulation of IL-18BP expression and control of the biological activity of IL-18 may be a therapeutic approach to LN patients.

Cytokines and their receptors as biomarkers of systemic lupus erythematosus

Systemic lupus erythematosus is the most clinically diverse autoimmune disease. Owing to its heterogeneous presentation, clinical management of systemic lupus erythematosus remains as one of the greatest challenges. Therefore, there is a great need to assess disease activity accurately. Biomarkers can be objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes or pharmacologic responses to a therapeutic intervention, and may also predict the risk of the disease, confirm diagnosis, monitor disease activity and provide prognostic information. Cytokines play an important and diverse role in the immune dysregulation in systemic lupus erythematosus. Measuring serum levels of soluble IL-2 receptor, IL-6, IL-10, soluble TNF receptor and IFN-alpha/IFN-induced genes may be promising biomarkers of disease activity in systemic lupus erythematosus.