Increased acylation-stimulating protein, C-reactive protein, and lipid levels in young women with polycystic ovary syndrome

Acylation stimulating protein/C3adesArg in the metabolic states: role of adipocyte dysfunction in obesity complications

Adipose tissue, as an endocrine organ, secretes several adipocyte-derived hormones named 'adipokines' that are implicated in regulating energy haemostasis. Substantial evidence shows that white adipose tissue-derived adipokines mediate the link between obesity-related exogenous factors (like diet and lifestyle) and various biological events (such as pre- and postmenopausal status) that have obesity consequences (cardiometabolic disorders). One of the critical aetiological factors for obesity-related diseases is the dysfunction of adipokine pathways. Acylation-stimulating protein (ASP) is an adipokine that stimulates triglyceride synthesis and storage in adipose tissue by enhancing glucose and fatty acid uptake. ASP acts via its receptor C5L2. The primary objective of this review is to address the existing gap in the literature regarding ASP by investigating its diverse responses and receptor interactions across multiple determinants of obesity. These determinants include diet composition, metabolic disorders, organ involvement, sex and sex hormone levels. Furthermore, this article explores the broader paradigm shift from solely focusing on adipose tissue mass, which contributes to obesity, to considering the broader implications of adipose tissue function. Additionally, we raise a critical question concerning the clinical relevance of the insights gained from this review, both in terms of potential therapeutic interventions targeting ASP and in the context of preventing obesity-related conditions, highlighting the potential of the ASP-C5L2 interaction as a pharmacological target. In conclusion, these findings validate that obesity is a low-grade inflammatory status with multiorgan involvement and sex differences, demonstrating dynamic interactions between immune and metabolic response determinants.

The effect of polycyclic aromatic hydrocarbon biomarkers on cardiovascular diseases

Polycyclic aromatic hydrocarbon (PAHs) are part of particulate matter (PM), which is produced from incomplete combustion of organic matter. Biomarkers mean biological indicators, molecules that indicate a normal or abnormal process in the body and may be a sign of a condition or disease. Studies show that PAHs increase the risk of cardiovascular diseases through processes such as oxidative stress, inflammation and atherosclerosis. The present study focused on the evaluation of health effects PAHs biomarkers on cardiovascular diseases (CVD). In this narrative study, data were collected from databases such as Scopus, PubMed, Web of science and Google Scholar in the period 1975-2023. After screening, duplicate and irrelevant articles were removed. Finally, 68 articles related to the effect of PAHs on CVD were included in the study. In addition to the articles found through the search in databases, another 18 articles from the references of the selected articles were included. According to the finding in during the biotransformation of PAH, a number of metabolites are made, such as phenols, diols, quinones, and epoxides. Phenolic isomers have the highest percentage and biomarkers used for their detection include 2-OHNAP used to trace naphthalene from heating processed food, 3-OHPHEN used to trace phenanthrene from diesel, 2-OHFLU used to trace fluorene and 1-OHPYR used to trace pyrene from cigarette and hookah smoke. According to the result, increasing blood pressure and heart rate and causing atherosclerosis are the main complications due to exposure to PAH metabolite on cardiovascular system. The most important agents that causes this affects including increased homocysteine, cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), serum biomarkers of C-reactive protein, and triglycerides. Result this study showed that cardiovascular diseases risk is increased by exposure to PAH biomarkers from smoking, car emissions, occupational exposure, and incinerators. Therefore, strict controls should be implemented for sources of PAH production and exposure.

Integrated bioinformatics analysis elucidates granulosa cell whole-transcriptome landscape of PCOS in China

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common reproductive, neuroendocrine, and metabolic disorder in women of reproductive age that affects up to 5-10% of women of reproductive age. The aetiology of follicle development arrest and critical issues regarding the abnormal follicular development in PCOS remain unclear. The present study aims to systematically evaluate granulosa cell whole-transcriptome sequencing data to gain more insights into the transcriptomic landscape and molecular mechanism of PCOS in China.

METHODS

In the present study, the microarray datasets GSE138518, GSE168404, GSE193123, GSE138572, GSE95728, and GSE145296 were downloaded from the Gene Expression Omnibus (GEO) database. Subsequently, differential expression analysis was performed on the PCOS and control groups, followed by functional interaction prediction analysis to investigate gene-regulatory circuits in PCOS. Finally, hub genes and their associated ncRNAs were validated by qPCR in human-luteinized granulosa (hGL) cells and were correlated with the clinical characteristics of the patients.

RESULTS

A total of 200 differentially expressed mRNAs, 3 differentially expressed miRNAs, 52 differentially expressed lncRNAs, and 66 differentially expressed circRNAs were found in PCOS samples compared with controls. GO and KEGG enrichment analyses indicated that the DEGs were mostly enriched in phospholipid metabolic processes, steroid biosynthesis and inflammation related pathways. In addition, the upregulated miRNA hsa-miR-205-5p was significantly enriched in the ceRNA network, and two hub genes, MVD and PNPLA3, were regulated by hsa-miR-205-5p, which means that hsa-miR-205-5p may play a fundamental role in the pathogenesis of PCOS. We also found that MVD and PNPLA3 were related to metabolic processes and ovarian steroidogenesis, which may be the cause of the follicle development arrest in PCOS patients.

CONCLUSIONS

In summary, we systematically constructed a ceRNA network depicting the interactions between the ncRNAs and the hub genes in PCOS and control subjects and correlated the hub genes with the clinical characteristics of the patients, which provides valuable insights into the granulosa cell whole-transcriptome landscape of PCOS in China.

Complement activation in polycystic ovary syndrome occurs in the postprandial and fasted state and is influenced by obesity and insulin sensitivity

OBJECTIVE

Polycystic ovary syndrome (PCOS) is associated with metabolic risk. Complement proteins regulate inflammation and lipid clearance but their role in PCOS-associated metabolic risk is unclear. We sought to establish whether the complement system is activated in PCOS in the fasting and postprandial state.

DESIGN

Case-control study.

PATIENTS

Fasting complement levels were measured in 84 women with PCOS and 95 healthy controls. Complement activation post-oral fat tolerance test (OFTT) was compared in 40 additional subjects (20 PCOS, 20 controls).

MEASUREMENTS

Activation pathway (C3, C4, C3a(desArg), factor B, factor H, properdin, Factor D) and terminal pathway (C5, C5a, terminal complement complex [TCC]) proteins were measured by commercial or in-house assays.

RESULTS

Fasting C3, C3a(desArg) and TCC concentrations were increased in insulin-resistant (adjusted differences: C3 0.13 g/L [95%CI 0-0.25]; C3a(desArg) 319.2 ng/mL [19.5-619]; TCC 0.66 μg/mL [0.04-1.28]) but not in insulin-sensitive women with PCOS. C3 and factor H levels increased with obesity. Post-OFTT, C3 and C4 levels increased to a similar extent in PCOS subjects and controls, whist factor H levels increased more in women with PCOS compared to controls (adjusted differences (area under the curve): 12 167 μg min/mL [4942-19 392]), particularly in the presence of concomitant obesity.

CONCLUSIONS

Activation and terminal complement pathway components are elevated in patients with PCOS, especially in the presence of insulin resistance and obesity.

Effect of Moderate Aerobic Exercise on Complement Activation Pathways in Polycystic Ovary Syndrome Women

BACKGROUND

The complement system is pivotal in host defense mechanisms, protecting against pathogenic infection by regulating inflammation and cell immunity. Complement-related protein activation occurs through three distinct pathways: classical, alternative, and lectin-dependent pathways, which are regulated by cascades of multiple proteins. Complement activation is recognized in polycystic ovary syndrome (PCOS) to be associated with obesity and insulin sensitivity. Exercise reduces insulin resistance and may help reduce obesity, and therefore, this study was undertaken to determine the effect of exercise on the activation of complement-related proteins in PCOS and control women.

SUBJECTS AND MEASUREMENTS

In this study, 10 controls and 11 PCOS subjects who were age- and weight-matched underwent an 8-week supervised exercise program at 60% maximal oxygen consumption. Weight was unchanged though insulin sensitivity was increased in PCOS subjects and controls. Fasting baseline and post-exercise samples were collected and 14 complement-related proteins belonging to classical, alternative, and lectin-dependent pathways were measured.

RESULTS

Baseline levels of complement C4b and complement C3b/iC3b were higher in PCOS (P < 0.05) compared with controls. Exercise reduced complement C1q (P < 0.05), C3 (P < 0.001), C4 (P < 0.01), factor B (P < 0.01), factor H (P < 0.01), and properdin (P < 0.05) in controls, but not in PCOS women.

CONCLUSION

Exercise induced complement changes in controls that were not seen in PCOS subjects, suggesting that these pathways remain dysregulated even in the presence of improved insulin sensitivity and not improved by moderate aerobic exercise.

CLINICAL TRIAL REGISTRATION

ISRCTN registry, ISRCTN42448814.

Roles of different n-3/n-6 PUFA ratios in ovarian cell development and steroidogenesis in PCOS rats

Polycystic ovary syndrome (PCOS) is a complex and common endocrine disorder characterized by hyperandrogenism, which is accompanied by follicle growth arrest at the small antral stage, minimal granulosa cell proliferation, and chronic anovulation. Polyunsaturated fatty acids (PUFAs) are necessary for the body's metabolism, growth and development. Although PUFAs play an important role in the regulation of female reproduction, their role in ovarian development in PCOS is still unclear. The present study was conducted to investigate the effects of different ratios of n-3/n-6 PUFAs (omega-3/omega-6) on ovary development in PCOS rats. Serum levels of reproductive hormones and enzymes related to steroidogenesis were assessed. The results indicated that PUFAs (n-3/n-6: 1/15) significantly increased ovarian weight and improved the ovarian structure although they had no significant effect on body weight in PCOS rats. Meanwhile, apoptosis was attenuated accompanied by increased cell proliferation by PUFAs (n-3/n-6: 1/15). Moreover, serum levels of hormones (FSH and E₂) were also significantly increased by PUFAs (n-3/n-6: 1/15) accompanied by decreased T levels. To investigate whether PUFAs regulate the expression of enzymes related to hormone synthesis, western blotting was used to determine the protein levels of CYP51, CYP19, StAR and 3β-HSD. The results showed that PUFAs significantly increased the protein levels of all of these enzymes. These results indicate that PUFAs enhance the reproductive performance of PCOS by increasing the expression of steroidogenesis enzymes, which are related to hormone secretion and ovarian functions. These findings provide evidence that a balanced n-3/n-6 PUFA ratio is beneficial for PCOS reproduction.

Role of Complement and Complement-Related Adipokines in Regulation of Energy Metabolism and Fat Storage

Adipose tissue releases many cytokines and inflammatory factors described as adipokines. In obesity, adipokines released from expanding adipose tissue are implicated in disease progression and metabolic dysfunction. However, mechanisms controlling the progression of adiposity and metabolic complications are not fully understood. It has been suggested that expanding fat mass and sustained release of inflammatory adipokines in adipose tissue lead to hypoxia, oxidative stress, apoptosis, and cellular damage. These changes trigger an immune response involving infiltration of adipose tissue with immune cells, complement activation and generation of factors involved in opsonization and clearance of damaged cells. Abundant evidence now indicates that adipose tissue is an active secretory source of complement and complement-related adipokines that, in addition to their inflammatory role, contribute to the regulation of metabolic function. This article highlights advances in knowledge regarding the role of these adipokines in energy regulation of adipose tissue through modulating lipogenic and lipolytic pathways. Several adipokines will be discussed including adipsin, Factor H, properdin, C3a, Acylation-Stimulating Protein, C1q/TNF-related proteins, and response gene to complement-32 (RGC-32). Interactions between these factors will be described considering their immune-metabolic roles in the adipose tissue microenvironment and their potential contribution to progression of adiposity and metabolic dysfunction. The differential expression and the role of complement factors in gender-related fat partitioning will also be addressed. Identifying lipogenic adipokines and their specific autocrine/paracrine roles may provide means for adipose-tissue-targeted therapeutic interventions that may disrupt the vicious circle of adiposity and disease progression. © 2019 American Physiological Society. Compr Physiol 9:1411-1429, 2019.

Effects of omega-3 polyunsaturated fatty acids on steroidogenesis and cellular development in PCOS rats

Polycystic ovary syndrome (PCOS) is a common endocrine disorder, which is characterized by hyperandrogenism.

The Effect of Atorvastatin (and Subsequent Metformin) on Adipose Tissue Acylation-Stimulatory-Protein Concentration and Inflammatory Biomarkers in Overweight/Obese Women With Polycystic Ovary Syndrome

Background: Atorvastatin has been shown to improve cardiovascular risk (CVR) indices in women with polycystic ovary syndrome (PCOS). Low-grade chronic inflammation of adipose tissue may link PCOS and adverse CVR. In pro-inflammatory states such as PCOS, spontaneous activation of the alternative pathway of complement results in increased generation of acylation stimulating protein (ASP) from adipocytes irrespective of body mass index. Methods: The objective of this study was to determine the effect of atorvastatin on markers of adipose tissue dysfunction and inflammation; acylation-stimulating-protein (ASP), interleukin-6 (IL-6), and monocyte-chemoattractant-protein-1 (MCP-1) in PCOS. This was a randomized, double-blind, placebo-controlled study where 40 medication-naive women with PCOS and biochemical hyperandrogenaemia were randomized to either atorvastatin 20 mg daily or placebo for 12 weeks. Following the 12 week randomization; both group of women with PCOS were subsequently started on metformin 1,500 mg daily for further 12 weeks to assess whether pre-treatment with atorvastatin potentiates the effects of metformin on markers of adipose tissue function We conducted a post-hoc review to detect plasma ASP and the pro-inflammatory cytokines IL6 and MCP-1 before and after 12 and 24 weeks of treatment. Results: There was significant reduction in ASP (156.7 ± 16.2 vs. 124.4 ± 14.8 ng/ml p <0.01), IL-6 (1.48 ± 0.29 vs.0.73 ± 0.34 pg/ml p = 0.01) and MCP-1 (30.4 ± 4.2 vs. 23.0 ± 4.5 pg/ml p = 0.02) after 12 weeks of atorvastatin that was maintained subsequently with 12 weeks treatment with metformin. There was a significant positive correlation between ASP levels with CRP (p < 0.01), testosterone (p < 0.01) and HOMA-IR (p < 0.01); IL-6 levels with CRP (p <0.01) and testosterone (p < 0.01) and MCP-1 with CRP (p < 0.01); testosterone (p < 0.01) and HOMA-IR (p < 0.02). Conclusions: This post-hoc analysis revealed that 12 weeks of atorvastatin treatment significantly decreased the markers of adipose tissue dysfunction and inflammation, namely ASP, IL-6 and MCP-1 in obese women with PCOS. Changes in adipose tissue markers were significantly associative with substantial improvements in HOMA-IR, testosterone and hs-CRP levels. ISRCTN Number: ISRCTN24474824.

An increase level of acylation stimulating protein is correlated with metabolic risk markers in North Indian obese women

BACKGROUND AND AIMS

The present study was to investigate the association between serum acylation stimulating protein (ASP) level with metabolic risk factors in North Indian obese women.

METHODS

This is a case control study, total n=322 women aged between 20 and 45 years (n=162 with metabolic syndrome & n=160 without metabolic syndrome) were recruited for the study according to National Cholesterol Education Program Treatment Panel (NCEPATP) guidelines. Serum ASP level were determined by enzyme linked immunosorbent assay.

RESULTS

Results indicated that circulating ASP and other metabolic risk factors (waist circumference, triglycerides, fasting plasma glucose etc) were significantly higher in women with metabolic syndrome (WmetS) than in women without syndrome (WometS) (p<0.001). Furthermore circulating ASP was significantly higher possitively correlated with waist circumference (r=0.51, p<0.001), triglyceride (r=0.56, p<0.001), glucose (r=0.70, p<0.001), and negatively correlated with high density lipoprotein(r=-0.56, p<0.001) in women with metabolic syndrome.

CONCLUSIONS

Conclusively circulating ASP was found to be significantly associated with hyperlipidemia, obesity and obesity related disorders in North Indian obese women.

Hyperandrogenemia Induced by Letrozole Treatment of Pubertal Female Mice Results in Hyperinsulinemia Prior to Weight Gain and Insulin Resistance

Women with polycystic ovary syndrome (PCOS) diagnosed with hyperandrogenism and ovulatory dysfunction have an increased risk of developing metabolic disorders, including type 2 diabetes and cardiovascular disease. We previously developed a model that uses letrozole to elevate endogenous testosterone levels in female mice. This model has hallmarks of PCOS, including hyperandrogenism, anovulation, and polycystic ovaries, as well as increased abdominal adiposity and glucose intolerance. In the current study, we further characterized the metabolic dysfunction that occurs after letrozole treatment to determine whether this model represents a PCOS-like metabolic phenotype. We focused on whether letrozole treatment results in altered pancreatic or liver function as well as insulin resistance. We also investigated whether hyperinsulinemia occurs secondary to weight gain and insulin resistance in this model or if it can occur independently. Our study demonstrated that letrozole-treated mice developed hyperinsulinemia after 1 week of treatment and without evidence of insulin resistance. After 2 weeks of letrozole treatment, mice became significantly heavier than placebo mice, demonstrating that weight gain was not required to develop hyperinsulinemia. After 5 weeks of letrozole treatment, mice exhibited blunted glucose-stimulated insulin secretion, insulin resistance, and impaired insulin-induced phosphorylation of AKT in skeletal muscle. Moreover, letrozole-treated mice exhibited dyslipidemia after 5 weeks of treatment but no evidence of hepatic disease. Our study demonstrated that the letrozole-induced PCOS mouse model exhibits multiple features of the metabolic dysregulation observed in obese, hyperandrogenic women with PCOS. This model will be useful for mechanistic studies investigating how hyperandrogenemia affects metabolism in females.

Association study of HNF1A in women with polycystic ovary syndrome

PURPOSE

This study aims to ascertain whether an association exists between hepatocyte nuclear factor 1 alpha (HNF1A) and polycystic ovary syndrome (PCOS).

METHODS

One thousand one hundred thirty-eight PCOS and 1125 healthy control Han Chinese women were recruited from Reproductive Hospital Affiliated to Shandong University. Serum hormone, blood lipid level, and genomic DNA were obtained from the peripheral blood for this research. Two single-nucleotide polymorphisms (SNPs)-rs2393791 and rs7305618-located in HNF1A were genotyped using the Sequenom MassARRAY system.

RESULTS

The allele frequencies of SNP rs7305618 had significant differences between PCOS patients and controls after adjusting for age and BMI (p = 0.023). Besides, PCOS patients carrying the rs7305618 CC genotype shown a higher testosterone level than the patients with CT + TT genotypes after being adjusted by age and BMI (p = 0.019).

CONCLUSIONS

A SNP located in the HNF1A gene is associated with PCOS among Han Chinese women. This suggested that variations in HNF1A might confer risk for PCOS.

Low acylation stimulating protein levels are associated with cardiometabolic disorders-secondary to autoimmune activation?

Objective:

We investigated the possible association of serum acylation stimulating protein (ASP) with cardiometabolic disorders and the evidence of autoimmune activation.

Methods:

Population-based randomly selected 1024 participants were cross-sectionally and prospectively analyzed. ASP concentrations were measured with a validated ELISA kit. Correlations were sought separately in subjects with no cardiometabolic disorders (n=427) designated as “healthy.”

Results:

ASP was positively correlated with total testosterone and inversely correlated with platelet activating factor (PAF), PAF-acetylhydrolase (AH), in each gender, and positively correlated in “healthy” men with lipoprotein [Lp](a) and apolipoprotein B. Correlations of ASP with PAF values ≥22 nmol/L were abolished, contrasted to a strongly inverse one in subjects with PAF <22 nmol/L. In linear regression analyses in the whole sample, ASP was inversely associated independently with PAF and PAF-AH and, in men, positively with Lp(a) and sex hormone-binding globulin. Prevalent and (at 2.0 years’ follow-up) incident metabolic syndrome (MetS, n=393), diabetes (n=154), and coronary heart disease (CHD, n=171) were analyzed by sex-, age-, and Lp(a)-adjusted logistic regression, using tertiles of ASP and PAF. The lower two (<42 nmol/L) ASP tertiles were a risk factor in combined sexes for MetS and diabetes. In women, incident CHD was predicted by either reduced or elevated ASP tertiles.

Conclusion:

Findings can be explained by the notion of operation of immune responses against both ASP and oxidized PAF-like lipids of Lp(a) to yield for “reduced” values and increased likelihood of cardiometabolic disorders.

Acute effects of exogenous hormone administration on postprandial acylation stimulating protein levels in ovariectomized rats after a fat load

Background. ASP, a potent lipogenic factor, was linked to female fat metabolism in association studies. Aim. To investigate acute effects of sex hormone treatment on postprandial ASP levels in vivo. Methods. 24 female rats were randomly divided into 4 groups including controls. The rats were ovariectomized and injected with progesterone, estrogen, or testosterone. An hour later, olive oil was administered orally. Plasma ASP and triglycerides were measured at several postprandial time points. Area under the curve (TG-AUC) represented TG clearance. Results. Only the progesterone treated group had a significant postprandial ASP increase at two hours compared to basal levels (439.8 ± 62.4 versus 253.4 ± 59.03 μg/mL, P = 0.04). Interestingly, increased ASP levels coordinated negatively with corresponding TG levels and TG-AUC postprandially, mostly evident in the opposite effects in the progesterone and testosterone treated groups. ASP levels increased 3-fold in the progesterone versus testosterone treated groups, whereas TG-AUC was significantly lower. Conclusion. These findings suggest that progesterone enhances ASP production and TG clearance simultaneously, supporting the notion of a stimulatory role for progesterone on ASP-mediated TG clearance. This is the first functional study demonstrating a cause-effect relationship between hormone treatment and ASP levels in vivo and may contribute to understanding the mechanism of progesterone function as a female lipogenic hormone.

Complement protein C3 and coronary artery calcium in middle-aged women with polycystic ovary syndrome and controls

Circulating complement protein C3 (C3) levels have been associated with coronary artery calcification (CAC) in women with systemic lupus erythematosus, but have yet to be evaluated in women with polycystic ovary syndrome (PCOS). We aimed to determine whether C3 levels were elevated in women with PCOS compared to controls and to quantify the association of C3 with cardiovascular disease (CVD) risk factors and CAC and if PCOS modified this association. This cross-sectional analysis included 132 women with PCOS and 155 controls, 35-62 years old, from the third visit of a case-control study. CAC was measured during the study visit, and circulating C3 was measured in stored sera. The presence of CAC and CAC categories (Agatston score 0, 1-9.9 and ≥ 10) were used for logistic and ordinal regression analysis, respectively. C3 levels were not significantly different between women with PCOS and controls. Among all women, C3 was associated with the presence of CAC and increasing CAC groups after adjusting for age, PCOS status and insulin or body mass index (BMI), all p<0.05. In addition, C3 was associated with the presence of CAC after adjusting for age, PCOS status, BMI, insulin and African American race, p=0.049. PCOS status did not modify these associations. In conclusion, circulating C3 levels may prove beneficial in identifying women at risk of CVD in women with PCOS and the general population.

Effects of sugar-sweetened beverages on plasma acylation stimulating protein, leptin and adiponectin: relationships with metabolic outcomes

OBJECTIVE

The effects of fructose and glucose consumption on plasma acylation stimulating protein (ASP), adiponectin, and leptin concentrations relative to energy intake, body weight, adiposity, circulating triglycerides, and insulin sensitivity were determined.

DESIGN AND METHODS

Thirty two overweight/obese adults consumed glucose- or fructose-sweetened beverages (25% energy requirement) with their ad libitum diets for 8 weeks, followed by sweetened beverage consumption for 2 weeks with a standardized, energy-balanced diet. Plasma variables were measured at baseline, 2, 8, and 10 weeks, and body adiposity and insulin sensitivity at baseline and 10 weeks.

RESULTS

Fasting and postprandial ASP concentrations increased at 2 and/or 8 weeks. ASP increases correlated with changes in late-evening triglyceride concentrations. At 10 weeks, fasting adiponectin levels decreased in both groups, and decreases were inversely associated with baseline intra-abdominal fat volume. Sugar consumption increased fasting leptin concentrations; increases were associated with body weight changes. The 24-h leptin profiles increased during glucose consumption and decreased during fructose consumption. These changes correlated with changes of 24-h insulin levels.

CONCLUSIONS

The consumption of fructose and glucose beverages induced changes in plasma concentrations of ASP, adiponectin, and leptin. Further study is required to determine if these changes contribute to the metabolic dysfunction observed during fructose consumption.

International Union of Basic and Clinical Pharmacology. [corrected]. LXXXVII. Complement peptide C5a, C4a, and C3a receptors

The activation of the complement cascade, a cornerstone of the innate immune response, produces a number of small (74-77 amino acid) fragments, originally termed anaphylatoxins, that are potent chemoattractants and secretagogues that act on a wide variety of cell types. These fragments, C5a, C4a, and C3a, participate at all levels of the immune response and are also involved in other processes such as neural development and organ regeneration. Their primary function, however, is in inflammation, so they are important targets for the development of antiinflammatory therapies. Only three receptors for complement peptides have been found, but there are no satisfactory antagonists as yet, despite intensive investigation. In humans, there is a single receptor for C3a (C3a receptor), no known receptor for C4a, and two receptors for C5a (C5a₁ receptor and C5a₂ receptor). The most recently characterized receptor, the C5a₂ receptor (previously known as C5L2 or GPR77), has been regarded as a passive binding protein, but signaling activities are now ascribed to it, so we propose that it be formally identified as a receptor and be given a name to reflect this. Here, we describe the complex biology of the complement peptides, introduce a new suggested nomenclature, and review our current knowledge of receptor pharmacology.

Serum free fatty acid levels in PCOS patients treated with glucophage, magnesium oxide and spironolactone

To assess the effect of glucophage, magnesium oxide and spironolactone in altering free fatty acids (FFAs), 36 PCOS women were randomly divided into three groups. Group 1 (n = 14) was treated with 500 mg glucophage po bid, group 2 (n = 10) was treated with 400 mg magnesium oxide po bid and group 3 (n = 12) was treated with 50 mg spironolactone po bid for 12 weeks. A glucose tolerance test with 75 g glucose load was performed before and after treatment, collecting blood at 0, 1 and 2 h for insulin, glucose, FFA and aldosterone. Amount of FFA before and after treatment were compared by repeated measure ANOVA and represented as area under the curve. FFA levels before treatment were 0.83 ± 0.23, 0.77 ± 0.15 and 0.85 ± 0.28 and after treatment were 0.77 ± 0.48, 0.71 ± 0.18 and 0.66 ± 0.25 for glucophage, magnesium oxide and spironolactone-treated patients, respectively. The FFA levels were unchanged in the groups treated with glucophage and magnesium oxide but were significantly (p < 0.03) decreased in the group treated with spironolactone. Since FFAs are known to be involved in the development of insulin resistance, these results suggest that spironolactone may be useful for lowering insulin resistance in PCOS patients.

Is the polycystic ovary syndrome the causative of the increase in inflammatory markers and metabolic risk?

AIMS

To investigate the relationship between the levels of C-reactive protein (CRP), interleukin-6 (IL-6) and IL-1β and the hormonal and metabolic alterations in women with polycystic ovary syndrome (PCO).

MATERIALS AND METHODS

Case-control study. CRP, IL-6 and IL-1β were evaluated in combination with obesity, insulin resistance (IR) and hyperandrogenism parameters in 20 patients with PCO. Twenty healthy women were used as the control.

RESULTS

The average CRP values was 5.1 in the cases vs. 0.8 mg/L in the control group (p < 0.0001). The IL-6 average values were 2.77 in the cases vs. 2.70 pg/ml in the control group (p = 0.254). IL-1β levels were found to be within the normal range in all individuals. A positive correlation was found between the CRP values and the IR (p < 0.0001) as well as with the presence of obesity (p < 0.02). No correlation was found between PCR and hyperandrogenemia (p = 0.4) nor between IL-6 values and IR (p = 0.3), or between the levels of this cytokine and the presence of hyperandrogenemia (p = 0.2). A significant correlation was found between IL-6 levels and obesity (p < 0.0001).

CONCLUSIONS

The present study demonstrates the presence of a chronic inflammation status in young women with PCO. These parameters are mainly related to obesity and, to a lesser extent, to IR.

Benefits of omega-3 Fatty acids supplementation on serum paraoxonase 1 activity and lipids ratios in polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common endocrine disorder associated with increased risk of cardiovascular disease. The purpose of this study was to investigate the ef¬fects of omega-3 fatty acids on serum paraoxonase 1 activity and lipids ratios in polycystic ovary syndrome.

METHODS

This double-blind randomized controlled clinical trial was conducted on 64 PCOS pa¬tients with 20-35 years old. Thirty two of the subjects had taken 4 g/day omega -3 fatty acids and 32 patients were given placebo for 8 weeks. Fasting blood samples, anthropometric measure¬ments and dietary intakes were collected at the beginning and the end of the study. Serum total cholesterol, triglyceride, and HDL-C were measured using the enzymatic methods. LDL-C con¬centration was calculated by the Friedewald formula and arylesterase activity of serum PON1 was measured. Data were analyzed using SPSS software.

RESULTS

Omega-3 fatty acids significantly decreased TC/HDL-C and LDL-C/HDL-C ratios (P = 0.009 for both) and significantly increased serum PON1 activity (P = 0.048) compared with placebo. Changes in TG/HDL-C ratio were not statistically significant in omega-3 fatty acids group at the end of the study in comparison to placebo group. Reduction in TC/HDL-C, LDL-C/HDL-C and TG/HDL-C ratios and increase in serum PON1 activity were also significant in omega-3 fatty acids group at the end of the study compared with baseline values (P <0.001, P < 0.001, P = 0.004, and P = 0.001, respectively).

CONCLUSION

Omega-3 fatty acids may decrease the risk for cardiovascular disease through the improvement in paraxonase-1 activity and reduction in some lipids ratio in PCOS women.

Recombinant acylation stimulating protein administration to C3-/- mice increases insulin resistance via adipocyte inflammatory mechanisms

Background

Complement 3 (C3), a key component of the innate immune system, is involved in early inflammatory responses. Acylation stimulating protein (ASP; aka C3adesArg), a C3 cleavage product, is produced in adipose tissue and stimulates lipid storage. We hypothesized that, depending on the diet, chronic ASP administration in C3^−/− mice would affect lipid metabolism and insulin sensitivity via an adaptive adipose tissue inflammatory response.

Methodology/Principal Findings

C3^−/− mice on normal low fat diet (ND) or high fat diet (HFD) were chronically administered recombinant ASP (rASP) for 25 days via an osmotic mini-pump. While there was no effect on food intake, there was a decrease in activity, with a relative increase in adipose tissue weight on ND, and a shift in adipocyte size distribution. While rASP administration to C3^−/− mice on a ND increased insulin sensitivity, on a HFD, rASP administration had the opposite effect. Specifically, rASP administration in C3^−/− HFD mice resulted in decreased gene expression of IRS1, GLUT4, SREBF1 and NFκB in muscle, and decreased C5L2 but increased JNK, CD36, CD11c, CCR2 and NFκB gene expression in adipose tissue as well as increased secretion of proinflammatory cytokines (Rantes, KC, MCP-1, IL-6 and G-CSF). In adipose tissue, although IRS1 and GLUT4 mRNA were unchanged, insulin response was reduced.

Conclusion

The effects of chronic rASP administration are tissue and diet specific, rASP administration enhances the HFD induced inflammatory response leading to an insulin-resistant state. These results suggest that, in humans, the increased plasma ASP associated with obesity and cardiovascular disease could be an additional factor directly contributing to development of metabolic syndrome, insulin resistance and diabetes.

Acylation stimulating protein reduction precedes insulin sensitization after BPD-DS bariatric surgery in severely obese women

OBJECTIVE

The mechanisms involved in early resolution of insulin resistance and type 2 diabetes mellitus after biliopancreatic diversion with duodenal switch (BPD-DS) surgery are still unknown. We evaluated early effects of BPD-DS on plasma acylation stimulating protein (ASP), an adipokine involved in lipid and glucose metabolism.

SUBJECTS

32 non-diabetic and 22 diabetic severely obese women (BMI40 kg m(-2)) were evaluated for body composition and plasma parameters before, 24 h, 5 days, 6 and 12 months after surgery.

RESULTS

Within the early postoperative period (24 h), ASP decreased 25 and 30% in non-diabetic and diabetic women, respectively (P<0.001). Twenty-four hours after surgery, triglyceride, cholesterol, HDL-Chol, LDL-Chol and C3 also decreased, while glucose, insulin and high-sensitivity C-reactive protein (hsCRP) increased (all P<0.001). By 5 days, without significant weight loss, the decreases in ASP, cholesterol, HDL-Chol and LDL-Chol levels were all maintained. At this time, glucose, insulin and HOMA-IR also decreased 11 to 52% (all P<0.001). At 6 and 12 months, with pronounced weight loss and decreased per cent fat mass, there were further decreases in ASP (maximal -56% non-diabetic, -61% diabetic, P<0.001), as well as in glucose, insulin, HOMA-IR, triglyceride, cholesterol, LDL-Chol, HDL-Chol and hsCRP levels. Improved insulin resistance/diabetes at 5 days was predicted by 24 h changes as follows: per cent change ASP, HDL-Chol, hsCRP and total cholesterol predicted HOMA-IR (5 days) (r(2)=0.454, P<0.001), and per cent change ASP, HDL-Chol and hsCRP predicted change (5 days vs baseline) in HOMA-IR (r(2)=0.351, P<0.001).

CONCLUSION

Acute postoperative decreases in ASP are associated with early improvement of insulin resistance/diabetes after BPD-DS surgery.

Plasma adipokine and hormone changes in mountaineers on ascent to 5300 meters

OBJECTIVE

The current study evaluated multiple metabolic and inflammatory hormone responses in recreational climbers (7 men and 3 women, age 26-49 years) over 9 days. In particular, acylation-stimulating protein (ASP), which influences fat storage in adipose tissue, has not been measured at high altitude.

METHODS

Serial measurements were taken at sea level (SL), or 353 m, on day 0, 4000 m on day 3, 4750 m on day 6, and 5300 m on day 9 of the expedition.

RESULTS

Body mass index (BMI) decreased upon ascent to 5300 m from SL (SL 23.2 ± 1.5 kg/m(2); 4000 m 23.2 ± 1.4 kg/m(2); 4750 m 22.9 ± 1.3 kg/m(2); 5300 m 22.3 ± 1.2 kg/m(2); P<.001). Similarly, plasma non-esterified fatty acids and triglycerides increased, while HDL cholesterol decreased (P<.05 to <.001) from SL to 5300 m. Acylation-stimulating protein (SL 42.2 ± 40.2 nm; 4000 m 117.0 ± 69.6 nm; 4750 m 107.9 ± 44.5 nm; 5300 m 82.2 ± 20.2 nm; P=.019) and adiponectin (SL 10.4 ± 6.5 ng/mL, 4000 m 13.9 ± 8.5 ng/mL, 4750 m 18.3 ± 8.3 ng/mL, 5300 m 14.7 ± 8.0 ng/mL; P=.015) increased, as did insulin and Interleukin-6 (IL-6) levels (up to 71% and 168%, respectively; P<.05) with no change in leptin, complement C3 (C3), high sensitivity C-reactive protein (hsCRP) or cortisol levels throughout the mountain ascent from SL to 5300 m.

CONCLUSION

Acylation-stimulating protein and adiponectin are increased during a 9-day period of high altitude (SL to 5300 m) exposure despite weight loss in healthy mountaineers.

Inflammatory-metabolic parameters in obese and nonobese normoandrogenemic polycystic ovary syndrome during metformin and oral contraceptive treatment

Our aim was to evaluate the optimal treatment strategy addressing cardiovascular risk in obese and nonobese patients with polycystic ovary syndrome (PCOS). We planned a prospectıve randomized clinical study. Normoandrogenemic and oligoamenorrheic women with PCOS and impaired glucose tolerance (n = 96) were enrolled in the study. Six months of treatment with metformin HCL or oral contraceptive pills (OCPs) were given to the patients. Group 1 were obese and receiving metformin. Group 2 were obese and receiving OCPs. Group 3 were nonobese and receiving metformin, and Group 4 were nonobese receiving OCPs. ADMA, homocysteine, high sensitive C-reactive protein (hs-CRP) and homeostasis model assessment estimate of insulin resistance (HOMA-IR) were investigated. ADMA, homocysteine, hs-CRP and HOMA-IR were similar in obese and nonobese groups before the treatment. After 6 months of treatment, a significant decrease was observed in ADMA, homocysteine and HOMA-IR levels in Groups 1 and 3. An increase in ADMA and hs-CRP levels was observed in Groups 2 and 4. In this study, metformin treatment leads to improvement in hormonal and metabolic parameters and decreases ADMA and homocysteine levels possibly independent of BMI. However, the use of oral contraceptives in obese and nonobese patients with PCOS with impaired glucose tolerance increases ADMA and hs-CRP levels and creates an increase in the metabolic risk.

Relation between C-reactive protein and body mass index in patients with polycystic ovarian syndrome

INTRODUCTION

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women. These patients share common features like obesity with metabolic syndrome. C-reactive protein (CRP) is a low-grade chronic inflammation biomarker that independently predicts high-risk patients for cardiovascular diseases (CVD). Although many studies showed increased plasma CRP levels in patients with PCOS, there is still less evidence that can link obesity and CRP levels in patients with PCOS. The objective of this study was to investigate the relations between body mass index (BMI) and CRP plasma levels in patients with PCOS.

METHOD

Forty patients with PCOS and 30 controls matched by age and BMI were included. Blood sample was obtained from all individuals in early follicular phase of menstrual cycle. CRP, fasting blood sugar (FBS), triglyceride (TG), and total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), blood pressure, waist circumference (WC) and BMI was measured for all subjects.

RESULT

CRP and TG levels were higher in patients with PCOS (p < 0.001 and p = 0.011, respectively). CRP level increased significantly only in patients with PCOS with BMI ≥ 25 kg/m(2) (p = 0.001) but was not significant in patients with PCOS with BMI < 25 kg/m(2) (p = 0.067). In further analysis, BMI and WC affect CRP rising in patients with PCOS (p = 0.001).

CONCLUSION

In patients with PCOS, serum CRP levels were higher than age and BMI-matched controls. Furthermore, BMI was strongly related to CRP only in overweight patients with PCOS.

Acute injection of ASP in the third ventricle inhibits food intake and locomotor activity in rats

Acylation-stimulating protein (ASP; also known as C3adesArg) stimulates triglyceride synthesis and glucose transport via interaction with its receptor C5L2, which is expressed peripherally (adipose tissue, muscle) and centrally. Previous studies have shown that ASP-deficient mice (C3KO) and C5L2-deficient mice (C5L2KO) are hyperphagic (59 to 229% increase, P < 0.0001), which is counterbalanced by increased energy expenditure measured as oxygen consumption (Vo(2)) and a lower RQ. The aim of the present study was to evaluate ASP's effect on food intake, energy expenditure, and neuropeptide expression. Male rats were surgically implanted with intracerebroventricular (icv) cannulas directed toward the third ventricle. After a 5-h fast, rats were injected, and food intake was assessed at 0.5, 1, 2, 4, 16, 24, and 48 h, with a 5- to 7-day washout period between each injection. Acute icv injections of ASP (0.3-1,065 pmol) had a time-dependent effect on decreasing food intake by 20 to 57% (P < 0.05). Decreases were detected by 30 min (maximum 57%, P < 0.01) and at the highest dose effects extended to 48 h (19%, P < 0.05, 24- to 48-h period). Daily body weight gain was decreased by 131% over the first 24 h and 29% over the second 24 h (P < 0.05). A conditioned taste aversion test indicated that there was no malaise. Furthermore, acute ASP injection affected energy substrate usage, demonstrated by decreased Vo(2) and RQ (P < 0.05; implicating greater fatty acid usage), with a 49% decrease in total activity over 24 h (P < 0.05). ASP administration also increased anorexic neuropeptide POMC expression (44%) in the arcuate nucleus, with no change in NPY. Altogether ASP may have central in addition to peripheral effects.

Acylation stimulating protein: a female lipogenic factor?

Acylation stimulating protein (ASP) is a potent lipogenic factor produced from adipocytes. Plasma ASP levels were shown to increase in obesity, diabetes mellitus type II and dyslipidemia, and decrease after weight loss and fasting. Growing evidence suggests that ASP may significantly contribute to subcutaneous fat storage in females. In vitro, ASP stimulated triglyceride synthesis to a larger extent in subcutaneous compared with omental adipocytes. The ASP receptor binding affinity to plasma membranes prepared from adipose tissue showed higher binding affinity to plasma membranes from female adipose tissue compared with male adipose tissue, and was more pronounced to subcutaneous compared with omental plasma membranes. Human studies demonstrated that postprandial triglyceride clearance predicted by ASP levels was more efficient in women than in men. In mice, postprandial triglyceride clearance, with intraperitoneal ASP administration, was faster in females compared with males. The ASP deficient mice were resistant to weight gain and had reduced fat mass that was more pronounced in females. Recent findings in humans and mice point to a significant association between progesterone and ASP variations in females. In this review, we highlight findings, to date, linking ASP to physiological and hormonal alterations that may contribute to subcutaneous fat distribution typical to females.

Meta-analysis of cardiovascular disease risk markers in women with polycystic ovary syndrome

BACKGROUND

The relation between polycystic ovary syndrome (PCOS) and cardiovascular disease (CVD) remains unclear. In an attempt to provide high-quality evidence on the relation between PCOS and CVD, relevant literature for CVD risk markers [C-reactive protein (CRP), homocysteine (Hcy), tumor necrosis factor-alpha (TNF-α), plasminogen activator inhibitor-1 (PAI-1), lipoprotein (a) [Lp(a)], advanced glycation end-products (AGEs), vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), asymmetric dimethylarginine (ADMA), endothelin-1 (ET-1) and fibrinogen] in women with PCOS was reviewed and analyzed.

METHODS

A systematic search was conducted electronically using specific eligibility criteria. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated and combined appropriately. To ensure synthesis of the best available evidence, sensitivity analyses were performed. RESULTS A total of 130 data sets were included in 11 different outcomes, involving 7174 and 5076 CVD markers in women with PCOS and controls, respectively. Women with PCOS demonstrated significantly elevated CRP [WMD (95% CI) 0.99 (0.77-1.21)], Hcy [2.25 (1.46-3.03)], PAI-1 antigen [16.96 (7.25-26.28)], PAI-1 activity [0.71 (0.18-1.23)], VEGF [1.72 (0.96-2.48)], ADMA [0.19 (0.08-0.3)], AGEs [3.91 (2.36-5.45)] and Lp(a) [0.81 (0.58-1.04)] concentrations compared with controls, yet with significant between-study heterogeneity. Borderline significance (not robust in the sensitivity analyses) was detected for TNF-α [0.75 (0.07-1.44)], ET-1 [1.06 (0.52-1.59)] and fibrinogen [0.20 (0.01-0.39)], whereas no difference was detected for IL-6 [0.71 (-0.16 to 1.59)]. CONCLUSIONS Women with PCOS have increased serum concentrations of CVD risk markers compared with controls. Whether this apparent risk is translated into increased incidence of CVD in later life remains to be elucidated.

Serum complement C3 has a stronger association with insulin resistance than high-sensitivity C-reactive protein in women with polycystic ovary syndrome

OBJECTIVE

To compare the association of complement C3 (C3) versus high-sensitivity C-reactive protein (hs-CRP) with insulin resistance (IR) in women with polycystic ovary syndrome (PCOS).

DESIGN

Cross-sectional analysis.

SETTING

Clinical research center in China.

PATIENT(S)

One hundred thirty-three women with PCOS and 116 healthy, age-matched controls were recruited.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

One hundred one women with PCOS and 20 controls underwent hyperinsulinemic-euglycemic clamp to assess their insulin sensitivity, which was expressed as an M value.

RESULT(S)

Compared with controls, women with PCOS had a lower M value and higher C3 (1.37 ± 0. 34 vs. 1.10 ± 0.22 g/L) and hs-CRP levels (1.46 ± 2.29 vs. 0.49 ± 0.88 mg/L). In women with PCOS, C3 and hs-CRP negatively correlated with M value (r = -0.61 and r = -0.47, respectively). By regression analysis, C3 was found to have a greater impact on the M value (standardized coefficient β = -0.24) than did hs-CRP (standardized coefficient β = -0.13). After adjusting for body mass index (BMI), women with PCOS in the upper quartile were 4.30 times more likely to exhibit IR compared with those in the lower quartiles, whereas hs-CRP was not a statistically significant predictor of IR in women with PCOS.

CONCLUSION(S)

Compared with hs-CRP, serum C3 might be a stronger inflammatory marker of IR in women with PCOS.

Relationship between C3 levels and common carotid intima-media thickness in overweight and obese patients

OBJECTIVE

The study aim was to compare C3 levels with the common carotid artery intima-media thickness (CCAIMT) in subjects of both genders, with a wide range of BMI, independently of age, gender, and abdominal obesity.

METHOD

140 euthyroid, mainly overweight/obese subjects (age 18-30 years) were examined. BMI, waist circumference, blood pressure, fasting insulin, glucose, lipids, C3 and C-reactive protein serum concentrations, and insulin resistance degree (estimated by homeostasis model assessment for insulin resistance (HOMAIR)) were measured.

RESULTS

CCA-IMT was positively (p < 0.001) correlated with BMI, waist circumference, systolic and diastolic blood pressures, HOMAIR, and insulin, CRP, and C3 serum levels. The multiple linear regression analysis showed that only male gender and waist circumference maintained an independent relation with the CCA-IMT.

CONCLUSION

This study suggests that central fat accumulation and male gender independently increase the thickness of the arterial wall, whereas inflammation and inflammatory markers do not have an independent effect on this parameter.

Circulating inflammatory markers in polycystic ovary syndrome: a systematic review and metaanalysis

OBJECTIVE

To perform a review and metaanalysis of the studies evaluating the status of serum inflammatory markers in women with polycystic ovary syndrome (PCOS).

DESIGN

Systematic review and metaanalysis of articles published in English before January 2010 and identified using the PubMed search engine.

SETTING

Academic hospital.

PATIENT(S)

Women with PCOS and appropriate controls.

INTERVENTION(S)

Measurement of serum concentrations of inflammatory markers by high-sensitivity techniques.

MAIN OUTCOME MEASURE(S)

Metaanalyses of the mean difference in serum C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations among patients with PCOS and appropriate controls, applying random-effects models to limit interstudy variability, and using appropriate estimates of evidence dissemination bias.

RESULT(S)

Metaanalysis of the 31 articles meeting inclusion criteria showed that circulating CRP was 96% higher in women with PCOS compared to controls (95% confidence interval, 71%-122%; z = 7.32) without evidence of dissemination bias (Egger's regression intercept, 0.45; 95% confidence interval, -2.30 to 3.21). These findings persisted after excluding five studies with mismatches in body mass, frequency of obesity, or both, between women with PCOS and controls. Metaanalyses involving 10 studies of IL-6, and nine studies of TNF-α revealed no statistically significant differences between PCOS and controls.

CONCLUSION(S)

Women with PCOS exhibit an elevation in circulating CRP that is independent of obesity. This finding corroborates existing molecular evidence of the chronic low-grade inflammation that may underpin the pathogenesis of this disorder.

Hormone and pharmaceutical regulation of ASP production in 3T3-L1 adipocytes

Several studies have demonstrated increases in acylation stimulating protein (ASP), and precursor protein C3 in obesity, diabetes and dyslipidemia, however the nature of the regulation is unknown. To evaluate chronic hormonal and pharmaceutical mediated changes in ASP and potential mechanisms, 3T3-L1 adipocytes were treated with physiological concentrations of relevant hormones and drugs currently used in treatment of metabolic diseases for 48 h. Medium ASP production and C3 secretion were evaluated in relation to changes in adipocyte lipid metabolism (cellular triglyceride (TG) mass, non-esterified fatty acid (NEFA) release and real-time FA uptake). Chylomicrons increased ASP production (up to 411 +/- 133% P < 0.05), while leptin, triiodothyronine, and beta-blockers atenolol and propranolol had no effect. Dexamethasone, lovastatin, rosiglitazone and rimonabant decreased ASP production (-53 to -85%, P < 0.05), associated with a decrease in the precursor protein C3 (-37% to -65%, P < 0.01). By contrast, epinephrine, progesterone, testosterone, angiotensin II and metformin also decreased ASP (-54% to -100%, P < 0.05), but without change in precursor protein C3, suggesting a direct effect on convertase activity, possibly mediated by interference (except metformin) due to marked increases in NEFA (5.6-31-fold, increased P < 0.05). Both lovastatin and metformin induced decreases in ASP were also associated with decreased TG mass (maximal -60%, P < 0.05) and real-time FA uptake (maximum -75%, P < 0.05), suggesting a change in adipocyte differentiation status. These in vitro results are consistent with in vivo ASP profiles in subjects, and suggest that ASP may be regulated through precursor C3 availability, convertase activity and differentiation status.

Growth patterns during childhood and the relationship with acylation-stimulating protein

BACKGROUND/OBJECTIVES

Acylation-stimulating protein (ASP) is an adipose tissue-derived hormone, which stimulates glucose and free fatty acid (FFA) uptake into adipocytes. Changes in ASP metabolism are associated with alterations in lipid metabolism. As postnatal catch-up growth has been associated with dyslipidaemia in later life, we investigated the association between ASP and birth size, adult size and different growth patterns during childhood.

METHODS

The associations were investigated by multiple regression analyses in 285 young adults, aged 18-24. Subsequently, differences in ASP were analysed in four clinically relevant subgroups, young adults either born small for gestational age with short stature (SGA-S) or with catch-up growth (SGA-CU), or born appropriate for gestational age with idiopathic short stature (ISS) or with normal stature (controls).

RESULTS

Weight gain during childhood, particularly fat accumulation, was positively related to ASP levels in early adulthood, independent of birth size, age and gender. Foetal growth, reflected by birth size, was not related to ASP levels. Between the subgroups, no differences in ASP were found, but SGA-CU and ISS subjects had significantly higher levels of FFA.

CONCLUSION

Exaggerated weight gain during childhood, but not foetal growth, contributes to alterations in ASP metabolism, which may be associated with impaired FFA uptake and delayed triglycerides clearance. Therefore, exaggerated weight gain during childhood should be prevented.

The effects of acylation stimulating protein supplementation VS antibody neutralization on energy expenditure in wildtype mice

BACKGROUND

Acylation stimulating protein (ASP) is an adipogenic hormone that stimulates triglyceride (TG) synthesis and glucose transport in adipocytes. Previous studies have shown that ASP-deficient C3 knockout mice are hyperphagic yet lean, as they display increased oxygen consumption and fatty acid oxidation compared to wildtype mice. In the present study, antibodies against ASP (Anti-ASP) and human recombinant ASP (rASP) were tested in vitro and in vivo. Continuous administration for 4 weeks via osmotic mini-pump of Anti-ASP or rASP was evaluated in wildtype mice on a high-fat diet (HFD) to examine their effects on body weight, food intake and energy expenditure.

RESULTS

In mature murine adipocytes, rASP significantly stimulated fatty acid uptake (+243% vs PBS, P < 0.05) while Anti-ASP neutralized the rASP response. Mice treated with Anti-ASP showed elevated energy expenditure (P < 0.0001), increased skeletal muscle glucose oxidation (+141%, P < 0.001), reduced liver glycogen (-34%, P < 0.05) and glucose-6-phosphate content (-64%, P = 0.08) compared to control mice. There was no change in body weight, food intake, fasting insulin, adiponectin, CRP or TG levels compared to controls. Interestingly, HFD mice treated with rASP showed the opposite phenotype with reduced energy expenditure (P < 0.0001) and increased body weight (P < 0.05), cumulative food intake (P < 0.0001) and liver glycogen content (+59%, P < 0.05). Again, there was no change in circulating insulin, adiponectin, CRP or TG levels, however, plasma free fatty acids were reduced (-48%, P < 0.05).

CONCLUSION

In vitro, Anti-ASP effectively neutralized ASP stimulated fatty acid uptake. In vivo, Anti-ASP treatment increased whole body energy utilization while rASP increased energy storage. Therefore, ASP is a potent anabolic hormone that may also be a mediator of energy expenditure.

Serum High-Sensitivity C-Reactive Protein and Homocysteine Changes During Hormonal Therapy in Women With Polycystic Ovary Syndrome: A Prospective, Matched Study

The study evaluated the effect of 5 hormonal regimes on serum levels of high-sensitivity C-reactive protein (hsCRP) and homocysteine (Hcy) in women with polycystic ovary syndrome (PCOS). Women with PCOS received (1) conjugated estrogens and cyproterone acetate (n = 22), (2) 17β-estradiol and cyproterone acetate (n = 17), (3) ethinyl-estradiol and cyproterone acetate (high dose; n = 20), (4) ethinyl-estradiol plus cyproterone acetate (low dose; n = 12), or (5) ethinyl-estradiol plus desogetrel (n = 12). Both hsCRP and Hcy levels were measured at baseline and after 4, 7, and 12 months. The 17β-estradiol/cyproterone acetate regime resulted in significant reduction of both hsCRP and Hcy levels (P < .001). The other 4 regimes only resulted in a reduction of Hcy levels (P < .001). In conclusion, the 17β-estradiol/cyproterone acetate regime had the most favorable effects in women with PCOS regarding serum levels of hsCRP and Hcy.

Framework for a systems approach to proteomic biomarker profiling in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in females of reproductive age, and its prevalence ranges between 6 and 8%. Associated problems include infertility, menstrual disorders, hirsutism and obesity. In addition, individuals with PCOS may be at increased risk of diabetes, endometrial cancer and, possibly, cardiovascular disease and breast cancer in later life. Biomarkers identified from proteomic analyses may help to improve the clinical management of PCOS, provided that new proteomic data can be integrated with existing knowledge and/or pathways implicated in disease etiology. In this study, a database of identity, descriptions and functions/pathways has been developed from 148 published proteomic biomarkers in PCOS. From analysis of the database, a variety of pathways possibly implicated in PCOS were determined, including those related to fibrinolysis, thrombosis, the antioxidant pathway and the immune system. This database, if developed further, will provide a framework for a systems approach to profiling biomarkers in the future.

High sensitive serum C-reactive protein and its relationship with other cardiovascular risk factors in normoinsulinemic polycystic ovary patients without metabolic syndrome

PURPOSE

The aims of the study were to investigate high sensitive serum C-reactive protein (HS-CRP) levels in normoinsulinemic polycystic ovary syndrome (PCOS) patients without metabolic syndrome and whether there was any relationship between HS-CRP and other cardiovascular risk factors such as obesity and serum lipids.

METHODS

A total of 52 normoinsulinemic PCOS women without metabolic syndrome and 48 normoandrogenic ovulatory women were enrolled in the study. Standard clinical examinations, and ultrasonographic and endocrine screening including FSH, LH, total testosterone, free testosterone, sex hormone-binding globulin, dehydroepiandrosterone sulfate, low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC) and triglyceride (TG) were measured. Normal insulin sensitivity was defined on the basis of fasting serum glucose and insulin levels, serum insulin response to an oral glucose tolerance test and homeostatic model of insulin resistance. HS-CRP was assessed spectrophotometrically.

RESULTS

PCOS patients had increased HS-CRP compared to the control group (P < 0.0001). HS-CRP was positively correlated with body mass index (BMI) (r = 0.44, P < 0.0001), waist-to-hip ratio (WHR) (r = 0.66, P < 0.0001), LDL (r = 0.62, P < 0.0001), TC (r = 0.56, P < 0.0001) and TG (r = 0.38, P < 0.0001), and negatively correlated with HDL (r = -0.45, P < 0.0001). There was also a strong association between HS-CRP and PCOS status (r = 0.69, P < 0.0001) in the study. Multivariate regression analysis demonstrated that BMI, WHR, LDL, HDL and PCOS status were also the independent variables that influenced HS-CRP in the overall group.

CONCLUSION

Elevated HS-CRP was associated with cardiovascular risk factors in normoinsulinemic PCOS without metabolic syndrome. These patients need more intensive screening or treatment for this disease.

Change in plasma acylation stimulating protein during euglycaemic-hyperinsulinaemic clamp in overweight and obese postmenopausal women: a MONET study

OBJECTIVE

Acylation-stimulating protein (ASP) has been shown to positively stimulate fatty acid esterification and glucose uptake in adipocytes. In vitro studies demonstrate that insulin stimulates ASP secretion from adipocytes. Individuals with obesity and/or metabolic disturbances (insulin resistance and type 2 diabetes) have increased plasma ASP.

DESIGN

The present study was designed to evaluate whether ASP levels are influenced by the metabolic profiles of overweight and obese postmenopausal women during a euglycaemic/hyperinsulinaemic clamp (EHC). Patients The study population consisted of 76 overweight and obese sedentary postmenopausal women.

MEASUREMENTS

We evaluated insulin sensitivity, plasma ASP levels, body composition including visceral adipose tissue area, blood lipid profiles, liver enzymes, peak aerobic capacity, resting metabolic rate (RMR) and total energy expenditure (TEE).

RESULTS

We observed wide interindividual variations of ASP levels during the EHC. Therefore, subjects were divided into three groups based on ASP changes. Negative ASP Responders (NAR; n = 24) showed a -20% or greater decrease in ASP levels while Positive ASP Responders (PAR; n = 42) displayed ASP fluctuations superior to +20%. Ten subjects had little or no ASP change and were considered as Zero ASP responders (ZAR). PAR women displayed a worse metabolic profile than NAR women, including higher BMI, visceral adipose tissue, fasting insulin levels, lean body mass, and alanine aminotransferase (ALT), a marker of impaired liver function. After adjustment for BMI, only ALT remained significantly different, while lean body mass (P = 0.08) and visceral adipose tissue (P = 0.07) remained marginally higher. Correlation analysis of all subjects demonstrated that fasting ASP levels correlated positively with albumin and VO(2 peak) and this association remained significant after adjustments for the effect of BMI. In addition, the percentage maximal change in ASP levels during the EHC was positively associated with BMI, lean body mass, visceral adipose tissue, fasting insulin, HOMA, TEE, RMR, ALT and AST.

CONCLUSION

Overall these results suggest that an elevated ASP response during the EHC is associated with metabolic disturbances in overweight and obese postmenopausal women.

Lipoprotein lipase deficiency is associated with elevated acylation stimulating protein plasma levels

Acylation stimulating protein (ASP, C3adesArg) is an adipose tissue derived hormone that stimulates triglyceride (TG) synthesis. ASP stimulates lipoprotein lipase (LPL) activity by relieving feedback inhibition caused by fatty acids (FA). The present study examines plasma ASP and lipids in male and female LPL-deficient subjects primarily with the P207L mutation, common in the population of Quebec, Canada. We evaluated the fasting and postprandial states of LPL heterozygotes and fasting levels in LPL homozygotes. Homozygotes displayed increased ASP (58-175% increase, P < 0.05-0.01), reduced HDL-cholesterol (64-75% decrease, P < 0.0001), and elevated levels of TG (19-38-fold, P < 0.0001) versus control (CTL) subjects. LPL heterozygotes with normal fasting TG (1.3-1.9 mmol/l) displayed increased ASP (101-137% increase, P < 0.05-0.01) and delayed TG clearance after a fatload; glucose levels remained similar to controls. Hypertriglyceridemics with no known LPL mutation also had increased ASP levels (63-192% increase, P < 0.001). High-TG LPL heterozygotes were administered a fatload before and after fibrate treatment. The treatment reduced fasting and postprandial plasma ASP, TG, and FA levels without changing insulin or glucose levels. ASP enhances adipose tissue fatty-acid trapping following a meal; however in LPL deficiency, high ASP levels are coupled with delayed lipid clearance.