TLR2 and TLR4 Surface and Gene Expression in White Blood Cells after Fasting and Oral Glucose, Lipid and Protein Challenges: Influence of Obesity and Sex Hormones.

We studied if macronutrients of the diet have different effects on leukocyte activation, and if these effects are influenced by sex hormones or obesity. We analyzed leukocyte cell surface and gene expression of toll-like receptors 2 and 4 (TLR2 and TLR4) during fasting and after macronutrient loads in women with polycystic ovary syndrome and female and male controls. Fasting TLR2 surface expression in neutrophils was higher in men than in women. Obese subjects presented higher TLR2 gene expression than nonobese individuals, particularly in men. In contrast, surface TLR4 expression was lower in men and in obese individuals. Postprandial cell-surface expression decreased similarly after all macronutrient loads. Neutrophil TLR2 decreased only in obese subjects whereas TLR4 showed a greater decrease in nonobese individuals. However, TLR2 gene expression increased after glucose ingestion and decreased during the lipid load, while TLR4 was induced in response to lipids and mostly to glucose. Postprandial TLR gene expression was not influenced by group of subjects or obesity. Both cell-surface and gene postprandial expression inversely correlated with their fasting levels. These responses suggest a transient compensatory response aiming to prevent postprandial inflammation. However, obesity and sex hormones showed opposite influences on surface expression of TLR2 and TLR4, but not on their gene expression, pointing to regulatory posttranscriptional mechanisms.

Plasma thiobarbituric acid reactive substances (TBARS) in young adults: Obesity increases fasting levels only in men whereas glucose ingestion, and not protein or lipid intake, increases postprandial concentrations regardless of sex and obesity.

SCOPE: Oxidative stress and damage participate in the pathophysiology of obesity and its metabolic complications. We studied the influence of sex, obesity, and ingestion of different macronutrients on fasting and postprandial thiobarbituric acid reactive substances (TBARS), which can be considered as an index of lipid peroxidation and oxidative damage. METHODS AND RESULTS: We studied 19 men and 17 women, out of whom nine men and eight women had obesity. We collected blood samples in the fasting state and, on alternate days, following the ingestion of 300 kcal in the form of glucose, lipids, or proteins. Fasting TBARS concentrations correlated with waist circumference and were increased in obese men compared with nonobese men. This increase was not, however, observed in women. TBARS concentrations showed a marked increase following the ingestion of glucose in parallel to the increase in plasma glucose when considering all subjects as a whole, but did not increase after the oral intake of lipids and proteins. CONCLUSION: Plasma TBARS concentrations are increased in the fasting state only in obese men in association with abdominal adiposity, and increases markedly after the ingestion of glucose, but not after oral intake of lipids and proteins, regardless of sex and obesity.

Association of TLR2 S450S and ICAM1 K469E polymorphisms with polycystic ovary syndrome (PCOS) and obesity.

Toll-like receptors (TLRs) are activated by inflammatory stimuli and influence endothelial functions, contributing to the pathogenesis of atherosclerosis. We investigate the influence of polymorphisms in the genes encoding toll-like receptor 2 (TLR2) and 4 (TLR4) and endothelial adhesion molecules on polycystic ovary syndrome (PCOS) and its interaction with obesity. Ten single nucleotide polymorphisms were genotyped in 305 women with PCOS and 166 non-hyperandrogenic control women. In obese women, TLR2 S450S and ICAM1 K469E polymorphisms differently influenced metabolic variables and PCOS, respectively. Irrespective of PCOS, variant alleles of TLR2 S450S increased triglycerides, fasting insulin levels, and insulin resistance in obese women. TLR2 S450S interacted with obesity and PCOS on androstenedione levels, mutant alleles were associated with increased androstenedione concentrations in all women, with the exception of obese patients with PCOS (P=0.034). Regarding ICAM1 K469E, homozygosis for K469 alleles was more frequent in PCOS, but only in obese women (P=0.014). K469 alleles were also related to increased body mass index (P=0.017) and diastolic blood pressure (P=0.034). Moreover, ICAM1 K469E interacted with obesity and PCOS on serum triglyceride levels (P=0.019) and with PCOS on serum sex hormone-binding globulin concentrations (P=0.006). In conclusion, TLR2 S450S and ICAM1 K469E polymorphisms may be associated with PCOS and metabolic comorbidities in obese women.

Mediators of low-grade chronic inflammation in polycystic ovary syndrome (PCOS).

Chronic low-grade subclinical inflammation has been increasingly recognized as an interposer in the endocrine, metabolic and reproductive disturbances that characterize the polycystic ovary syndrome (PCOS). Abdominal adiposity and obesity are often present in PCOS. Mounting evidence indicates that adipose tissue is involved in innate and adaptive immune responses. Continuous release of inflammatory mediators such as cytokines, acute phase proteins, and adipokines perpetuates the inflammatory condition associated with obesity in women with PCOS, possibly contributing to insulin resistance and other long-term cardiometabolic risk factors. Genetic variants in the genes encoding inflammation-related mediators underlie the development of PCOS and their interaction with environmental factors may contribute to the heterogeneous clinical phenotype of this syndrome. In the future, strategies ameliorating inflammation may prove useful for the management of PCOS and associated conditions.

Circulating markers of oxidative stress and polycystic ovary syndrome (PCOS): a systematic review and meta-analysis.

BACKGROUND Oxidative stress might be associated with polycystic ovary syndrome (PCOS), but relatively small studies published to date do not permit reaching a definitive conclusion. We aimed at conducting a systematic review and meta-analysis of studies evaluating circulating markers of oxidative stress in patients with PCOS. METHODS We conducted a systematic review of studies reporting circulating markers of oxidative stress in women with PCOS and controls published up to June 2012, using Entrez PubMed and EMBASE online facilities. Meta-analysis calculated standardized mean differences (SMDs) and 95% confidence intervals (95CI). RESULTS From 1633 potential studies identified electronically, 68 studies, including 4933 PCOS patients and 3671 controls, were selected. For each of nine circulating markers of oxidative stress, an individual meta-analysis was conducted. Compared with control women, patients with PCOS presented higher circulating concentrations of homocysteine (23% increase, SMD 0.6, 95CI, 0.4-0.8), malondialdehyde (47% increase, SMD 1.9, 95CI 1.2-2.6) and asymmetric dimethylarginine (36% increase, SMD 1.1, 95CI 0.6-1.6), and increased superoxide dismutase activity (34% increase, SMD 1.0, 95CI 0.5-1.4) and decreased glutathione levels (50% decrease, SMD -3.7, 95CI -6.2 to -1.2) and paraoxonase-1 activity (32% decrease, SMD -0.9, 95CI -1.3 to -0.4). Similar results were found when restricting the analyses to studies in which patients and controls were matched for age and body mass index. CONCLUSIONS Circulating markers of oxidative stress are abnormal in women with PCOS independent of weight excess. This finding suggests that oxidative stress may participate in the pathophysiology of this common disorder.

Temporal trends of circulating nitric oxide and pro-inflammatory cytokine responses ex vivo in intra-abdominal sepsis: results from a cohort study.

OBJECTIVE AND DESIGN: To evaluate the association of pro-inflammatory mediators with organ dysfunction and adverse outcome in intra-abdominal sepsis patients. SUBJECTS: Twenty-one patients admitted to the Intensive Care Unit (ICU) were prospectively included in the study. Only patients with surgical diagnosis of intra-abdominal sepsis were enrolled. RESULTS: Tumor necrosis factor-α (TNFα) and interleukin (IL)-6 produced ex vivo were significantly lower in non-survivors on admission (p = 0.021) and day 2 (p = 0.013), respectively. Nitric oxide (NO(x)) levels were significantly higher in non-survivors from the onset of sepsis and until day 4 after diagnosis (p < 0.05). Circulating lymphocyte counts were lower in non-survivors after admission over time, but there was no association with impaired cytokine production in this group of patients during the entire follow-up. All non-survivors developed nosocomial pneumonia concomitantly with multiple organ dysfunction and septic shock. There was a significant correlation between nitric oxide (NO(x)) concentrations and the sequential organ failure assessment (SOFA) score at day 2 (r = 0.598, p = 0.009), and ICU stay (r = 0.605, p = 0.006). Continuously high NO(x) levels correlated with organ failure. The pro-inflammatory mediators TNFα, IL-6 and NO(x), and also the Simplified Acute Physiology Score II (SAPS-II), discriminate survivors from non-survivors. According to logistic regression models, although these parameters are independently associated with the outcome, they do not improve the predictive power of the SAPS-II score for mortality risk. CONCLUSIONS: Disturbances in inflammatory responses and increase in NO(x) generation seem to characterize early intra-abdominal sepsis, in which immune suppression is associated with an increased susceptibility to nosocomial infections. Sequential NO(x) determinations could be a useful approach for improving the management of patients with intra-abdominal sepsis.

TNFalpha production in whole blood cultures from healthy individuals.

Tumor necrosis factor alpha (TNFalpha) is a major mediator of inflammatory responses and also plays a prominent role in bridging the innate and adaptive phases of immunity. In the present work we attempted to study TNFalpha production in endotoxin-stimulated blood of healthy individuals, and the inter-individual variability in TNFalpha production. For this study, we used diluted whole blood stimulated with lipopolysaccharide (LPS). The levels of the pro-inflammatory cytokine TNFalpha were measured by ELISA and by the L929 cytotoxicity bioassay in 16 and 18 healthy donors, respectively. There were highly significant inter-individual variations in the induced TNFalpha production. It is worth noting that there was no difference in sensitivity between ELISA and the cytotoxicity L929 bioassay. We concluded that whole blood culture is a sensitive method to determine the pro-inflammatory cytokine production in response to endotoxin stimuli in a relevant physiologic milieu. Our data indicate that this method provides appropriate information about the state of cellular immunity of the individual.