Association of obesity with leukocyte count in obese individuals without metabolic syndrome

AIMS

Inflammation in obesity is associated to insulin resistance (IR), hyperglycemia, hypertension and hyperlipidemia. Leukocytes play an important role in obesity associated inflammation. The initial factors that generate the inflammatory events in the obesity remain unclear. Therefore, the aim of this study was to determine the association of circulating leukocytes with clinical and biochemical parameters in obese individuals with clinical and biochemical parameters in normal range and with or without IR.

METHODS

Nineteen obese non-diabetic and 9 lean subjects were studied for serum levels of insulin, lipids, glycated hemoglobin, glycemia, for clinical parameters as HOMA-IR, arterial pressure and anthropometric parameters, and for leukocyte counts. Neutrophil/lymphocyte ratio (N/L) was calculated using the loge of leukocyte counts. Association between leukocytes and studied parameters was determined by Pearson's correlation.

RESULTS

Two groups of obese individuals were observed: with high levels of insulin (with IR) and with normal levels (without IR). Positive correlations were observed between leukocyte and lymphocyte counts with body mass index and HOMA-IR and negative correlation with decreased HDL levels. Lymphocytes correlated with increased levels of insulin. Leukocytes and neutrophils correlated positively with increased visceral fat and liver steatosis. These associations were absent in the obese group without IR. N/L ratio did not show correlations with studied parameters. The leukocyte associations were mainly observed in obese individuals with IR.

CONCLUSIONS

These data may represent initial leukocyte associations with morbidity features and define two different obese individuals that may evolve to the chronic inflammation observed in the obesity.

What non-alcoholic fatty liver disease has got to do with obstructive sleep apnoea syndrome and viceversa?

Non-alcoholic fatty liver disease (NAFLD) and obstructive sleep apnoea syndrome (OSAS) are common conditions, frequently encountered in patients with obesity and/or metabolic syndrome. NAFLD and OSAS are complex diseases that involve an interaction of several intertwined factors. Several lines of evidence lend credence to an immune system derangement in these patients, i.e. the low grade chronic inflammation status, reckoned to be the most important factor in causing and maintaining these two illnesses. Furthermore, it is emphasized the main role of spleen involvement, as a novel mechanism. In this review the contribution of the visceral adiposity in both NAFLD and OSAS is stressed as well as the role of intermittent hypoxia. Finally, a post on the prevention of systemic inflammation is made.

What non-alcoholic fatty liver disease has got to do with obstructive sleep apnoea syndrome and viceversa?

Non-alcoholic fatty liver disease (NAFLD) and obstructive sleep apnoea syndrome (OSAS) are common conditions, frequently encountered in patients with obesity and/or metabolic syndrome. NAFLD and OSAS are complex diseases that involve an interaction of several intertwined factors. Several lines of evidence lend credence to an immune system derangement in these patients, i.e. the low grade chronic inflammation status, reckoned to be the most important factor in causing and maintaining these two illnesses. Furthermore, it is emphasized the main role of spleen involvement, as a novel mechanism. In this review the contribution of the visceral adiposity in both NAFLD and OSAS is stressed as well as the role of intermittent hypoxia. Finally, a post on the prevention of systemic inflammation is made.

Critical periods of increased fetal vulnerability to a maternal high fat diet

BACKGROUND

Fetal adaptations to high fat (HF) diet in utero (IU) that may predispose to Metabolic Syndrome (MetS) in adulthood include changes in fetal hepatic gene expression. Studies were performed to determine whether maternal exposure to HF diet at different stages during pregnancy had different effects on the fetus, including hepatic gene expression.

METHODS

Female wild type mice were fed either a HF or breeding chow (C) for 2 wks prior to mating. The experimental groups were composed of embryonic day (e) 18.5 fetuses obtained from WT female mice that were fed HF (HF, 35.5% fat) or breeding chow (C, 9.5% fat) for 2 wk before mating until e9.5 of pregnancy (periconception-midpregnancy). At e9.5 dams were switched to the opposite diet (C-HF or HF-C).

RESULTS

Exposure to HF diet throughout pregnancy reduced maternal weight gain compared to C diet (p < 0.02 HF vs. C). HF-C dams had significantly decreased adiponectin levels and litter size when compared to C-HF (p < 0.02 HF-C vs C-HF). Independent of the timing of exposure to HF, fetal weight and length were significantly decreased when compared to C diet (HF, C-HF and HF-C vs. C p < 0.02). HF diet during the second half of pregnancy increased expression of genes in the fetal liver associated with fetal growth (C-HF vs C p < 0.001), glucose production (C-HF vs C p < 0.04), oxidative stress and inflammation (C-HF vs C p < 0.01) compared to C diet.

CONCLUSIONS

This model defines that there are critical periods during gestation in which the fetus is actively shaped by the environment. Early exposure to a HF diet determines litter size while exposure to HF during the second half of pregnancy leads to dysregulation of expression of key genes responsible for fetal growth, hepatic glucose production and oxidative stress. These findings underscore the importance of future studies designed to clarify how these critical periods may influence future risk of developing MetS later in life.

Involvement of proteasome and macrophages M2 in the protection afforded by telmisartan against the acute myocardial infarction in Zucker diabetic fatty rats with metabolic syndrome

This study investigated the involvement of proteasome and macrophages M2 in the protection afforded by telmisartan against the acute myocardial infarction in Zucker diabetic fatty (ZDF) rats with metabolic syndrome. ZDF rats were treated for three weeks with telmisartan at doses of 7 and 12 mg/kg/day. After treatment, rats were subjected to a 25 min occlusion of the left descending coronary artery followed by 2 h reperfusion (I/R). At the end of the I/R period, biochemical, immunohistochemical, and echocardiographic evaluations were done. Telmisartan treatment (7 mg/kg and 12 mg/kg) reduced the myocardial infarct size, the expression of proteasome subunits 20S and 26S, and the protein ubiquitin within the heart. The compound has led to an increased M2 macrophage phenotype within the cardiac specimens and a modification of the cardiac cytokine and chemokine profile. This was functionally translated in improved cardiac performance as evidenced by echography after 2 h reperfusion. 7 mg/kg/day telmisartan was sufficient to improve the left ventricular ejection fraction LVEF of the rat heart recorded after I/R (e.g., vehicle 38 ± 2.2%; telmisartan 54 ± 2.7%) and was sufficient to improve the diastolic function and the myocardial performance index up to values of 0.6 ± 0.01 measured after I/R.

[THE CLINIC AND FUNCTIONAL PECULIARITIES OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE'S COURSE, ACCOMPANIED WITH METABOLIC SYNDROME]

The article contains the data's of clinical course peculiarities, heart geometry construction and the systemic inflammatory processes activity in patients with chronic obstructive pulmonary disease, accompanied with metabolic syndrome. It was determined, that there high level of inflammatory processes activity, the big disturbances in heart geometry construction and more year pointes were te characteristic features of combined pathology.

Microbiota and diabetes: an evolving relationship

The gut microbiota affects numerous biological functions throughout the body and its characterisation has become a major research area in biomedicine. Recent studies have suggested that gut bacteria play a fundamental role in diseases such as obesity, diabetes and cardiovascular disease. Data are accumulating in animal models and humans suggesting that obesity and type 2 diabetes (T2D) are associated with a profound dysbiosis. First human metagenome-wide association studies demonstrated highly significant correlations of specific intestinal bacteria, certain bacterial genes and respective metabolic pathways with T2D. Importantly, especially butyrate-producing bacteria such as Roseburia intestinalis and Faecalibacterium prausnitzii concentrations were lower in T2D subjects. This supports the increasing evidence, that butyrate and other short-chain fatty acids are able to exert profound immunometabolic effects. Endotoxaemia, most likely gut-derived has also been observed in patients with metabolic syndrome and T2D and might play a key role in metabolic inflammation. A further hint towards an association between microbiota and T2D has been derived from studies in pregnancy showing that major gut microbial shifts occurring during pregnancy affect host metabolism. Interestingly, certain antidiabetic drugs such as metformin also interfere with the intestinal microbiota. Specific members of the microbiota such as Akkermansia muciniphila might be decreased in diabetes and when administered to murines exerted antidiabetic effects. Therefore, as a 'gut signature' becomes more evident in T2D, a better understanding of the role of the microbiota in diabetes might provide new aspects regarding its pathophysiological relevance and pave the way for new therapeutic principles.

Rescue of glucocorticoid-programmed adipocyte inflammation by omega-3 fatty acid supplementation in the rat

BACKGROUND

Adverse fetal environments predispose offspring to pathologies associated with the metabolic syndrome. Previously we demonstrated that adult offspring of dexamethasone-treated mothers had elevated plasma insulin and pro-inflammatory cytokines, effects prevented by a postnatal diet enriched with omega (n)-3 fatty acids. Here we tested whether prenatal glucocorticoid excess also programmed the adipose tissue phenotype, and whether this outcome is rescued by dietary n-3 fatty acids.

METHODS

Offspring of control and dexamethasone-treated mothers (0.75 μg/ml in drinking water, day 13 to term) were cross-fostered to mothers on a standard (Std) or high n-3 (Hn3) diet at birth. Offspring remained on these diets post-weaning, and serum and retroperitoneal fat were obtained at 6 months of age (n = 5-8 per group). Serum was analysed for blood lipids and fatty acid profiles, adipocyte cross sectional area was measured by unbiased stereological analysis and adipose expression of markers of inflammation, glucocorticoid sensitivity and lipid metabolism were determined by RT-qPCR analysis.

RESULTS

Serum total fatty acid levels were elevated (P < 0.01) in male offspring of dexamethasone-treated mothers, an effect prevented by Hn3 consumption. Prenatal dexamethasone also programmed increased adipose expression of Il6, Il1b (both P < 0.05) and Tnfa (P < 0.001) mRNAs regardless of fetal sex, but again this effect was prevented (for Il6 and Il1b) by Hn3 consumption. Offspring of dexamethasone-treated mothers had increased adipose expression of Gr (P = 0.008) and Ppara (P < 0.05) regardless of sex or postnatal diet, while 11bHsd1 was upregulated in males only. The Hn3 diet increased Ppard expression and reduced adipocyte size in all offspring (both P < 0.05) irrespective of prenatal treatment.

CONCLUSIONS

Prenatal glucocorticoid exposure programmed increased expression of inflammatory markers and enhanced glucocorticoid sensitivity of adipose tissue. Partial prevention of this phenotype by high n-3 consumption indicates that postnatal dietary manipulations can limit adverse fetal programming effects on adipose tissue.

[Evaluation of prognostic factors for the development of cholelithiasis in patients with metabolic syndrome]

The aim of study to determine the leading clinical and immunological parameters, reflecting the high risk of development and progression of gallstone disease in patients with metabolic syndrome.

MATERIALS AND METHODS

An assessment of clinical, biochemical and immunological parameters in 54 patients with gallstone disease associated with the metabolic syndrome and in comparison groups (31 with metabolic syndrome without gallstone disease and 29 with gallstone disease only) were made. For modeling the significant correlation and prediction of the effect of different combinations of factors on the risk of gallstone disease formation in patients with metabolic syndrome was used the multiple logistic regression analysis.

RESULTS

In accordance with our results the main risk factors of gallstone formation in patients with metabolic syndrome are the age (P = 0.02), waist volume (P = 0.0002), the increase of serum concentration of GGTP (P = 0.00001), MMP-9 (P = 0.002) and TIMP-1 (P = 0.02).

CONCLUSION

The results of our study have shown that in patients with metabolic syndrome was estimated the high risk of gallstone disease formation compared and the most significant factors of it formation are the patients age, waist volume and increase of serum concentration of GGTP, MMP-9 and TIMP-1.

Exercise induced adipokine changes and the metabolic syndrome

The lack of adequate physical activity and obesity created a worldwide pandemic. Obesity is characterized by the deposition of adipose tissue in various parts of the body; it is now evident that adipose tissue also acts as an endocrine organ capable of secreting many cytokines that are though to be involved in the pathophysiology of obesity, insulin resistance, and metabolic syndrome. Adipokines, or adipose tissue-derived proteins, play a pivotal role in this scenario. Increased secretion of proinflammatory adipokines leads to a chronic inflammatory state that is accompanied by insulin resistance and glucose intolerance. Lifestyle change in terms of increased physical activity and exercise is the best nonpharmacological treatment for obesity since these can reduce insulin resistance, counteract the inflammatory state, and improve the lipid profile. There is growing evidence that exercise exerts its beneficial effects partly through alterations in the adipokine profile; that is, exercise increases secretion of anti-inflammatory adipokines and reduces proinflammatory cytokines. In this paper we briefly describe the pathophysiologic role of four important adipokines (adiponectin, leptin, TNF-α, and IL-6) in the metabolic syndrome and review some of the clinical trials that monitored these adipokines as a clinical outcome before and after exercise.

Increased expression of Fc-γ receptors on monocytes in patients with nascent metabolic syndrome

CONTEXT

The metabolic syndrome (MetS) confers an increased propensity for diabetes and cardiovascular disease. C-reactive protein (CRP) levels are increased in MetS and predict cardiovascular events. Fc-γ receptors (FcgRs) are immune receptors on macrophages and include FcgRI (CD64), FcgRII (CD32), and FcgRIII (CD16).

OBJECTIVE

CRP has been shown to be processed by CD32 and CD64 in human monocytes. Although MetS is characterized by increased CRP and monocyte proinflammatory activity, data on FcgR expression on monocytes in patients with MetS compared with those of control subjects are sparse. Thus, the aim of the study was to examine this expression and the correlation with CRP.

DESIGN AND SETTING

After informed consent was given, patients with MetS (n = 50) and control subjects (n = 40) were studied. CD32 and CD64 expression on monocytes was examined by both flow cytometry and Western blotting. Immunoprecipitation studies were performed to examine spleen tyrosine kinase (Syk) activity as a measure of CD32 and CD64 activity.

RESULTS

Surface expression of CD32 and CD64 was significantly increased in patients with MetS compared with that in control subjects even after adjustment for body mass index and waist circumference. Expression of these FcgRs increased significantly with the number of features of MetS (Ptrend < .001) and correlated with levels of high-sensitivity CRP (P < .01). CRP after engagement of CD32 and CD64 signals via Syk. Syk phosphorylation was increased in monocytes of patients with MetS compared with that in control subjects.

CONCLUSIONS

We provide novel evidence of increased FcgR expression and activity in monocytes of patients with MetS that correlates with the number of features of MetS and with high-sensitivity CRP.

Asymmetric dimethylarginine serum levels in non-diabetic ankylosing spondylitis patients undergoing TNF-α antagonist therapy

OBJECTIVES

This paper aims to determine whether disease activity, systemic inflammation and metabolic syndrome are potential determinants of circulating asymmetric dimethylarginine (ADMA) in ankylosing spondylitis (AS) patients undergoing TNF-α antagonist-infliximab-therapy.

METHODS

We investigated ADMA serum concentrations in a series of 30 non-diabetic AS patients without history of cardiovascular (CV) events that were treated with the TNF-α antagonist infliximab, immediately prior to an infliximab infusion. Correlations of ADMA serum levels with disease activity, systemic inflammation and metabolic syndrome were assessed. Also, potential changes in ADMA concentration following an infusion of the anti-TNF-α monoclonal antibody-infliximab were analysed.

RESULTS

A higher concentrations of ADMA in men (p=0.012) and patients with hypertension was found (p=0.001). There was also a marginally positive correlation of ADMA serum levels with C-reactive protein levels (p=0.08). Moreover, a significant negative correlation between ADMA levels and total cholesterol and LDL-cholesterol was observed (p= 0.05). No differences in ADMA levels according to the specific clinical features of the disease were seen. A single infliximab infusion did not lead to significant changes in ADMA serum levels.

CONCLUSIONS

In AS patients undergoing periodical treatment with the anti-TNF-α monoclonal antibody-infliximab a link between some features of metabolic syndrome and ADMA concentrations was observed.

Latent autoimmune diabetes in adults is perched between type 1 and type 2: evidence from adults in one region of Spain

BACKGROUND

The aim of this study was to characterize the clinical characteristics and insulin secretion in adults with latent autoimmune diabetes in adults (LADA). We also compared these characteristics in subjects with antibody-negative type 2 diabetes (T2DM) or adult-onset type 1 diabetes (T1DM) to subjects with LADA.

METHODS

In this cross-sectional study, 82 patients with LADA, 78 with T1DM and 485 with T2DM were studied. Clinical and metabolic data, in particular those that related to metabolic syndrome, fasting C-peptide and islet-cell autoantibodies [glutamic acid decarboxylase (GADAb) and IA2 (IA2Ab)] were measured.

RESULTS

The frequency of metabolic syndrome in patients with LADA (37.3%) was higher than in those with T1DM (15.5%; p = 0.005) and lower than in patients with T2DM (67.2%; p < 0.001). During the first 36 months of the disease, the C-peptide concentration in LADA patients was higher than in subjects with T1DM but was lower than in T2DM patients (p < 0.01 for comparisons). Glycemic control in LADA patients (HbA1c 8.1%) was worse than in patients with T2DM (HbA1c 7.6%; p =0.007). An inverse association between GADAb titers and C-peptide concentrations was found in subjects with LADA (p < 0.001). Finally, LADA patients rapidly progressed to insulin treatment.

CONCLUSIONS

As in other European populations, patients with LADA in Spain have a distinct metabolic profile compared with patients with T1DM or T2DM. LADA is also associated with higher impairment of beta-cell function and has worse glycemic control than in T2DM. Beta cell function is related to GADAb titers in patients with LADA.

Differential proinflammatory and oxidative stress response and vulnerability to metabolic syndrome in habitual high-fat young male consumers putatively predisposed by their genetic background

The current nutritional habits and lifestyles of modern societies favor energy overloads and a diminished physical activity, which may produce serious clinical disturbances and excessive weight gain. In order to investigate the mechanisms by which the environmental factors interact with molecular mechanisms in obesity, a pathway analysis was performed to identify genes differentially expressed in subcutaneous abdominal adipose tissue (SCAAT) from obese compared to lean male (21–35 year-old) subjects living in similar obesogenic conditions: habitual high fat dietary intake and moderate physical activity. Genes involved in inflammation (ALCAM, CTSB, C1S, YKL-40, MIF, SAA2), extracellular matrix remodeling (MMP9, PALLD), angiogenesis (EGFL6, leptin) and oxidative stress (AKR1C3, UCHL1, HSPB7 and NQO1) were upregulated; whereas apoptosis, signal transcription (CITED 2 and NR3C1), cell control and cell cycle-related genes were downregulated. Interestingly, the expression of some of these genes (C1S, SAA2, ALCAM, CTSB, YKL-40 and tenomodulin) was found to be associated with some relevant metabolic syndrome features. The obese group showed a general upregulation in the expression of inflammatory, oxidative stress, extracellular remodeling and angiogenic genes compared to lean subjects, suggesting that a given genetic background in an obesogenic environment could underlie the resistance to gaining weight and obesity-associated manifestations.

Primary hypertension in children and adolescents is an immuno-metabolic disease with hemodynamic consequences

With the rise in obesity epidemic primary hypertension (PH) is now one of the most common chronic diseases in adolescence. In contrast to hypertensive adults, hypertensive children usually are not exposed to other comorbidities such as diabetes, chronic kidney disease and atherosclerosis. Thus, PH in children and adolescents can be treated as the early stage of development of cardiovascular disease. There is increasing amount of data indicating that PH is not only hemodynamic phenomenon but a complex syndrome involving disturbed activity of sympathetic nervous system, metabolic abnormalities and activation of innate and adaptive immune system. We discuss results of the studies on clinical, metabolic and immunological phenotype of hypertensive children, associations between metabolic and immunological abnormalities with target organ damage and results of antihypertensive treatment.

Leptin and visfatin serum levels in non-diabetic ankylosing spondylitis patients undergoing TNF-α antagonist therapy

OBJECTIVES

This paper aims to determine whether disease activity, systemic inflammation and metabolic syndrome are potential determinants of circulating leptin and visfatin levels in ankylosing spondylitis (AS) patients undergoing TNF-α antagonist therapy. We also assessed whether the infusion of infliximab may alter circulating leptin and visfatin concentrations in these patients.

METHODS

We investigated leptin and visfatin serum concentrations in a series of 30 non-diabetic AS patients without history of cardiovascular (CV) events that were treated with the TNF-α antagonist infliximab, immediately prior to an infliximab infusion. Leptin and visfatin levels were also determined immediately after administration of an infliximab dose.

RESULTS

Significant differences in leptin concentrations between men (8.85±5.31 ng/ml) and women (18.96±9.72 ng/ml) were observed (p=0.001). A significant correlation between visfatin concentrations and insulin resistance (HOMA at the time of the study) was found (r= 0.493; p=0.009). Circulating leptin and visfatin concentrations did not correlate with disease duration, erythrocyte sedimentation rate, C-reactive protein, BASDAI and VAS at the time of the study and adiponectin and resistin levels prior to infliximab infusion. Likewise, no differences in leptin and visfatin concentrations were observed when patients with a history of anterior uveitis or presence of syndesmophytes were compared with the remaining patients who did not exhibit these features. Leptin and visfatin levels did not change upon infliximab administration.

CONCLUSIONS

The present study indicates that in non-diabetic patients with AS on treatment with infliximab leptin and visfatin serum levels do not correlate with disease activity or systemic inflammation. Nevertheless, visfatin concentration correlates with insulin resistance.

Apelin serum levels in non-diabetic ankylosing spondylitis patients undergoing TNF-α antagonist therapy

OBJECTIVES

To determine whether disease activity, systemic inflammation and metabolic syndrome are potential determinants of circulating apelin in ankylosing spondylitis (AS) patients undergoing TNF-α antagonist-infliximab therapy.

METHODS

We investigated apelin serum concentrations in a series of 30 non-diabetic AS patients without history of cardiovascular (CV) events that were treated with the TNF-α antagonist infliximab, immediately prior to an infliximab infusion. Correlations of apelin serum levels with disease activity, systemic inflammation and metabolic syndrome were assessed. Also, potential changes in apelin concentration following an infusion of the anti-TNF-α monoclonal antibody-infliximab were analysed.

RESULTS

No significant correlation between apelin concentration and demographic features, inflammation, adiposity and metabolic syndrome features was seen. Neither differences were seen in basal apelin in different categorical variables associated to AS. Following infliximab infusion, a reduction of apelin serum levels was observed. In this regard, the median (interquartile range) values of apelin decreased from 0.99 (0.74-1.25) ng/ml immediately prior to infliximab infusion to 0.92 (0.72-1.39) ng/ml at the end of the infusion (time 120 minutes). However, the reduction in apelin serum levels following administration of the drug did not achieve statistical significance.

CONCLUSIONS

The present study shows that in non-diabetic patients with AS on treatment with infliximab apelin serum levels do not correlate with disease activity or metabolic syndrome. A single infusion of infliximab does not yield a significant change of apelin serum levels in AS patients.

Elevated concentration of oxidized LDL together with poor cardiorespiratory and abdominal muscle fitness predicts metabolic syndrome in young men

BACKGROUND

Metabolic syndrome (MetS) is associated with increased oxidized LDL (ox-LDL), systemic inflammation, and poor cardiorespiratory fitness. We examined affiliations of these factors and the effect of muscular fitness on MetS in young healthy men.

METHODS

Physical fitness, ox-LDL, tumor necrosis factor α (TNFα), interleukin-6 (IL-6) and serum lipids were measured in a nationally representative sample of Finnish young men with and without MetS. Participants (mean age 25.1years) performed tests of maximal oxygen uptake (VO₂max) and muscle fitness, and were divided into MetS (n=54, IDF 2007 criteria) and non-MetS (n=790). Age, smoking and leisure-time physical activity were used as covariates (ANCOVA).

RESULTS

The MetS group had lower results in VO₂max and all of the muscular fitness tests (excluding grip strength) (P<0.0001, in all). Ox-LDL, ox-LDL/HDL-cholesterol, ox-LDL/LDL-cholesterol, TNFα and IL-6 were all higher in the MetS group than in the non-MetS group (P<0.01, in all). In stepwise multivariate logistic regression analysis (adjusted to MetS criteria), higher ox-LDL (OR 1.118, 95% CI 1.078-1.160), lower VO₂max (OR 0.938, 95% CI 0.901-0.977) and lower sit-ups (OR 0.898, 95% CI 0.844-0.956) predicted MetS (p<0.05, in all).

CONCLUSIONS

Young men with MetS possess significantly poorer cardiorespiratory and muscle fitness, together with elevated systemic levels of ox-LDL, TNFα and IL-6 compared to non-MetS young men. Of these variables, ox-LDL, VO₂max and sit-ups predicted MetS. Based on these findings, poor physical fitness and elevated concentration of ox-LDL are significant predisposing factors in the development of MetS.

Components of the interleukin-6 transsignalling system are associated with the metabolic syndrome, endothelial dysfunction and arterial stiffness

OBJECTIVE

The metabolic syndrome (MetS) is an increasing epidemiologic challenge and cardiovascular risk factor. Interleukin-6 (IL-6) is a cytokine that exerts its biological function via a complex orchestration of soluble and membrane bound receptors. We have investigated associations between IL-6 and its soluble receptors, soluble IL-6 receptor (sIL-6r) and soluble glycoprotein 130 (sGP130) and the metabolic syndrome. Furthermore, we have investigated possible associations with endothelial dysfunction and arterial stiffness.

METHODS

A total of 563 subjects were included in this study. The Adult Treatment Panel III criteria of the National Cholesterol Education Program were used for the definition of MetS. We used commercially available ELISA to analyse circulating levels of the markers. Pulse wave propagation time (PWP) was determined to assess arterial stiffness.

RESULTS

The criteria for having MetS were filled by 221 subjects. sGP130, sIL-6r and IL-6 levels were elevated in subjects with MetS (p<0.05 for all markers), and are associated with increasing components of MetS. Particularly hypertriglyceridaemia, hypertension and fasting plasma glucose (FPG) seem to carry this association. sGP130 (p<0.01), IL-6 (p<0.05) and partially sIL-6r (p<0.05) correlated with markers of endothelial function (E-selectin, I-CAM-1, V-CAM-1) and inversely with PWP after adjustment for relevant covariates.

CONCLUSION

sGP130, sIL-6r and IL-6 were significantly elevated in subjects with MetS. In addition, sGP130, IL-6 and partially sIL-6r were associated with markers of endothelial function and arterial stiffness. This finding sheds new light on the role of these inflammatory cytokines in subjects with MetS and the development and progression of clinically silent atherosclerosis.

Dyslipidaemia in juvenile dermatomyositis: the role of disease activity

OBJECTIVES

To evaluate the presence of dyslipidaemia in JDM and its possible risk factors.

METHODS

Twenty-five JDM patients were compared to 25 healthy controls according to demographic data, body composition, fasting lipoproteins, glycaemia, insulin, antibodies and muscle enzymes. JDM scores were assessed: CMAS, MMT, DAS, MYOACT and MYTAX.

RESULTS

Abnormal lipid profile was found in nine patients and four controls (36% vs. 16%, p=0.196). JDM patients demonstrated significant higher levels of triglycerides (TG) [80(31-340) vs. 61(19-182) mg/dL, p=0.011] and higher frequency of abnormal levels of high density lipoproteins (HDL) (28% vs. 4%, p=0.04) when compared to controls. JDM patients with dyslipidaemia demonstrated significant lower median of HDL levels [29(0-49) vs. 50(39-72) mg/dL, p=0.0005], higher frequency of low HDL levels (77% vs. 0%, p=0.0001), higher TG levels [128(31-340) vs. 69(46-138) mg/dL, p=0.011], and also a higher frequency of increased levels of TG (44% vs. 0%, p=0.01), and TC (33% vs. 0%, p=0.03) when compared to those without this condition. Positive anti-LPL antibody was detected in just one JDM patient with abnormal lipid profile. JDM with dyslipidaemia had higher ESR (26 vs. 1 4.5mm/1sthour, p=0.006), CRP (2.1 vs. 0.4mg/dL, p=0.01), DAS (6 vs. 2, p=0.008), MYOACT(0.13 vs. 0.01, p=0.012), MYTAX(0.06vs.0,p=0.018), and lower scores of CMAS (47 vs. 52, p=0.024) and MMT (78 vs. 80, p=0.001) compared to JDM without dyslipidaemia. Positive correlations were detected between TG levels and CRP (r=0.697, p=0.001), DAS (r=0.610, p=0.001), MYOACT (r=0.661, p=0.001), MYTAX (r=0.511, p=0.008), and negative correlations with CMAS (r=-0.506, p=0.009) and MMT (r=-0.535, p=0.005). No differences were found between these groups regarding body composition, lipodystrophy, anti-LPL antibodies, and treatment except by higher frequency of cyclosporine current use in patients with dyslipidaemia (33% vs. 0%, p=0.03).

CONCLUSIONS

Dyslipidaemia in JDM patients was characterised by increased levels of TG and low levels of HDL. Disease activity and cyclosporine use were the mainly factors associated to these abnormalities.

Evolving research in nongenomic actions of aldosterone

PURPOSE OF REVIEW

Aldosterone is now recognized as an increasingly important contributor to cardiometabolic pathology via inflammatory and fibrosis-related pathways in addition to its classically described role in sodium and volume regulation. Consequently, much effort has been directed towards characterizing the molecular pathways involved in aldosterone-mediated fibrosis and inflammation. What was once viewed as straightforward steroid hormone biology is now appreciated as a highly complex and tightly regulated series of pathways and interactions. These recognitions have fuelled a multidisciplinary effort to identify precisely how aldosterone mediates intracellular activation of both genomic (latent) and nongenomic (rapid) mechanisms of influence. This review will explore recent novel pathways regulating aldosterone action, focusing on the nongenomic pathways.

RECENT FINDINGS

Several recent discoveries have redefined our understanding of aldosterone interactions at the cellular level. This includes activation of the mineralocorticoid receptor at the plasma membrane instead of via classical nuclear hormone receptor interaction, and identification of novel cofactor scaffolding proteins that modify aldosterone influence at the cellular level. In addition, aldosterone activation of secondary messenger system cascades can occur directly and independent of mineralocorticoid receptor interaction.

SUMMARY

Substantial progress in detailing the molecular biology of aldosterone regulation and action should facilitate study of how it exerts detrimental effects in cardiometabolic diseases. However, to date, the clinical impact of these discoveries has not been validated. Translational efforts are now required to determine if novel therapeutic targets can be developed.

Omega-3 fatty acids reduce adipose tissue macrophages in human subjects with insulin resistance

Fish oils (FOs) have anti-inflammatory effects and lower serum triglycerides. This study examined adipose and muscle inflammatory markers after treatment of humans with FOs and measured the effects of ω-3 fatty acids on adipocytes and macrophages in vitro. Insulin-resistant, nondiabetic subjects were treated with Omega-3-Acid Ethyl Esters (4 g/day) or placebo for 12 weeks. Plasma macrophage chemoattractant protein 1 (MCP-1) levels were reduced by FO, but the levels of other cytokines were unchanged. The adipose (but not muscle) of FO-treated subjects demonstrated a decrease in macrophages, a decrease in MCP-1, and an increase in capillaries, and subjects with the most macrophages demonstrated the greatest response to treatment. Adipose and muscle ω-3 fatty acid content increased after treatment; however, there was no change in insulin sensitivity or adiponectin. In vitro, M1-polarized macrophages expressed high levels of MCP-1. The addition of ω-3 fatty acids reduced MCP-1 expression with no effect on TNF-α. In addition, ω-3 fatty acids suppressed the upregulation of adipocyte MCP-1 that occurred when adipocytes were cocultured with macrophages. Thus, FO reduced adipose macrophages, increased capillaries, and reduced MCP-1 expression in insulin-resistant humans and in macrophages and adipocytes in vitro; however, there was no measureable effect on insulin sensitivity.

Histidine supplementation improves insulin resistance through suppressed inflammation in obese women with the metabolic syndrome: a randomised controlled trial

AIMS/HYPOTHESIS

Increased inflammation and oxidative stress are associated with insulin resistance (IR) and metabolic disorders. Serum histidine levels are lower and are negatively associated with inflammation and oxidative stress in obese women. The objective of this study was to evaluate the efficacy of histidine supplementation on IR, inflammation, oxidative stress and metabolic disorders in obese women with the metabolic syndrome (MetS).

METHODS

A total of 100 obese women aged 33-51 years with BMI ≥ 28 kg/m² and diagnosed with MetS were included following a health examination in the community hospital in this randomised, double-blinded, placebo-controlled trial. Participants were allocated to interventions by an investigator using sequentially numbered sealed envelopes and received 4 g/day histidine (n = 50) or identical placebo (n = 50) for 12 weeks. Participants then attended the same clinic every 2 weeks for scheduled interviews and to count tablets returned. Serum histidine, HOMA-IR, BMI, waist circumference, fat mass, serum NEFA, and variables connected to inflammation and oxidative stress were measured at baseline and 12 weeks. Participants, examining physicians and investigators assessing the outcomes were blinded to group assignment. In addition, the inflammatory mechanisms of histidine were also explored in adipocytes.

RESULTS

At 12 weeks, a total of 92 participants completed this trail. Compared with the placebo group (n = 47), histidine supplementation significantly decreased HOMA-IR (-1.09 [95% CI -1.49, -0.68]), BMI (-0.86 kg/m² [95% CI -1.55, -0.17]), waist circumference (-2.86 cm [95% CI -3.86, -1.86]), fat mass (-2.71 kg [95% CI -3.69, -1.73]), serum NEFA (-173.26 μmol/l [95% CI -208.57, -137.94]), serum inflammatory cytokines (TNF-α, -3.96 pg/ml [95% CI -5.29, -2.62]; IL-6, -2.15 pg/ml [95% CI -2.52, -1.78]), oxidative stress (superoxide dismutase, 17.84 U/ml [95% CI 15.03, 20.65]; glutathione peroxidase, 13.71 nmol/ml [95% CI 9.65, 17.78]) and increased serum histidine and adiponectin by 18.23 μmol/l [95% CI 11.74, 24.71] and 2.02 ng/ml [95% CI 0.60, 3.44] in histidine supplementation group (n = 45), respectively. There were significant correlations between changes in serum histidine and changes of IR and its risk factors. No side effects were observed during the intervention. In vitro study indicated that histidine suppresses IL6 and TNF mRNA expression and nuclear factor kappa-B (NF-κB) protein production in palmitic acid-induced adipocytes in a dose-dependent manner, and these changes were diminished by an inhibitor of NF-κB.

CONCLUSIONS/INTERPRETATION

Histidine supplementation could improve IR, reduce BMI, fat mass and NEFA and suppress inflammation and oxidative stress in obese women with MetS; histidine could improve IR through suppressed pro-inflammatory cytokine expression, possibly by the NF-κB pathway, in adipocytes.