PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (642377)

Clipboard (0)
None

Related Articles

1.  Maternal Serum Adiponectin Multimers in Preeclampsia 
Journal of perinatal medicine  2009;37(4):349-363.
Objective
Obesity, insulin resistance, and dyslipidemia are associated with preeclampsia. Recently, “adipose tissue failure”, characterized by dysregulation of adipokine production, has been implicated in the pathophysiology of these metabolic complications. Adiponectin, an insulin-sensitizing, anti-atherogenic, anti-inflammatory and angiogenic adipokine, circulates in oligomeric complexes including: low-molecular-weight (LMW) trimers, medium-molecular-weight (MMW) hexamers and high-molecular-weight (HMW) isoforms. These multimers exert differential biological effects, and HMW to total adiponectin ratio (SA) has been reported to be a specific marker of adiponectin activity. The aim of this study was to determine whether preeclampsia is associated with changes in circulating adiponectin multimers.
Study design
This cross-sectional study included women with: 1) normal pregnancy (n=225); and 2) patients with mild preeclampsia (n=111). The study population was further stratified by first trimester BMI (normal weight <25 kg/m2 vs. overweight/obese ≥25 kg/m2). Serum adiponectin multimers (total, HMW, MMW and LMW) concentrations were determined by ELISA. Non-parametric statistics were used for analysis.
Results
1) The median maternal HMW and LMW adiponectin concentrations were lower in patients with preeclampsia than in those with normal pregnancies (p<0.001 and p=0.01, respectively); 2) patients with preeclampsia had a lower HMW/Total adiponectin ratio (p<0.001) and higher MMW/Total adiponectin and LMW/Total adiponectin ratios than those with a normal pregnancy (p<0.001 and p=0.009, respectively); 3) the presence of preeclampsia was independently associated with lower maternal serum HMW adiponectin concentrations (p=0.001) and with a low HMW/Total adiponectin ratio (p<0.001) after correction for maternal age, maternal BMI, the difference in BMI between the third and the first trimester, and gestational age at sampling; and 4) overweight/obese pregnant women had a lower median total and HMW adiponectin concentration than normal weight pregnant women among women with normal pregnancies, but not among those with preeclampsia.
Conclusion
1) Preeclampsia is associated with a lower median concentration of the HMW adiponectin isoform, the most active form of this adipokine, and a low HMW/Total adiponectin ratio, a specific marker of adiponectin biologic activity; 2) in contrast to normal pregnancy, preeclampsia is not associated with decreased circulating adiponectin multimers in overweight/obese individuals suggesting altered regulation of this adipokine in preeclampsia; 3) collectively, these findings suggest that preeclampsia is characterized by alterations in adiponectin multimers and their relative distribution implying a role for adiponectin multimers in the mechanism of disease in preeclampsia.
doi:10.1515/JPM.2009.085
PMCID: PMC3166229  PMID: 19348608
Adipokines; Pregnancy; High-molecular-weight (HMW) adiponectin; Medium-molecular-weight (MMW) adiponectin; Low-molecular-weight (LMW) adiponectin; BMI; overweight; obesity
2.  Serum Adipokines and Adipose Tissue Distribution in Rheumatoid Arthritis and Ankylosing Spondylitis. A Comparative Study 
Rheumatoid arthritis (RA) and ankylosing spondylitis (AS) are inflammatory rheumatic diseases that may modify body composition. Adipose tissue has the ability to release a wide range of products involved in physiologic functions, but also in various pathological processes, including the inflammatory/immune response. RA and AS are both associated with the development of cardiovascular complications. It is has been established that central/abdominal, and particularly intra-abdominal or visceral adiposity is closely linked to cardiovascular events. Thus, in this study, we aimed to evaluate the body composition of patients with RA or AS compared to healthy controls (HC), with a special emphasis on the visceral region. In parallel, we measured adipose products or adipokines, namely leptin, adiponectin and its high molecular weight (HMW) isoform, resistin, and ghrelin, a gastric peptide that plays a role in energetic balance. The homeostasis model assessment for insulin resistance (HOMA-IR) and atherogenic index were used to evaluate cardiovascular risk. One hundred and twelve subjects were enrolled (30 patients with RA, 31 with AS, and 51 HC). Body composition was measured using dual-energy X-ray absorptiometry to determine total fat mass and lean mass, adiposity, fat in the android and gynoid regions, and visceral fat. Patients and HC did not differ in terms of body mass index. On the contrary, adiposity was increased in RA (p = 0.01) while visceral fat was also increased, but only in women (p = 0.01). Patients with AS tended to have lower total fat mass (p = 0.07) and higher lean mass compared to HC (p = 0.07). Leptin and leptin/fat mass were decreased in male patients with AS (p < 0.01), while total adiponectin and the ratio of HMW to total adiponectin were both increased in RA (p < 0.01). There were no changes in serum resistin and ghrelin in any group of patients. HOMA-IR and the atherogenic index were not modified in RA and AS. These results confirm that body composition was altered in RA and AS, affecting distinct soft tissue compartments. The effect of the increased visceral adipose tissue on cardiovascular risk is presumably attenuated by the favorable cardiometabolic profile in women with RA, as suggested by the normal HOMA-IR and atherogenic index.
doi:10.3389/fimmu.2013.00453
PMCID: PMC3861781  PMID: 24379815
fat mass; body composition; visceral fat; leptin; adiponectin; cardiovascular risk
3.  Distribution of Adiponectin Multimeric Forms In Chinese Women With Polycystic Ovary Syndrome and Their Relation To Insulin Resistance 
Objective
Adiponectin, an abundant adipokine with insulin sensitizing properties, exists different multimeric forms, including low molecular weight (LMW), medium molecular weight (MMW), and high molecular weight (HMW) species. Alterations in the distribution of adiponectin multimers and the relationship between adiponectin multimers and insulin resistance (IR) in women with the polycystic ovary syndrome (PCOS) remain unclear. To compare adiponectin multimerization status and estimate of insulin sensitivity in Chinese women with PCOS compared with age and body mass index (BMI)-matched controls.
Methods
Cross-sectional study involving 64 Chinese women with PCOS and 59 normal women. Circulating total adiponectin and its multimeric forms were determined by ELISA and insulin resistance was estimated using the homeostasis assessment insulin resistance index (HOMA-IR).
Results
After controlling for BMI status, levels of both total and HMW adiponectin were significantly lower in women with PCOS compared with normal women (P<0.05). Furthermore, HMW adiponectin provided a stronger contribution to models predicting insulin resistance than total adiponectin. Lastly, decreased HMW adiponectin was associated with increased HOMA-IR in both normal and PCOS women, and this association was independent of both overall adiposity and visceral adiposity.
Conclusion
Levels of both total and HMW adiponectin are decreased in Chinese women with PCOS compared with normal control women and the differences in HMW adiponectin persists after controlling for BMI. Furthermore, HMW adiponectin is a stronger predictor of insulin resistance in both women with PCOS and normal women than total adiponectin.
doi:10.1530/EJE-10-0021
PMCID: PMC3683393  PMID: 20530094
Polycystic ovary syndrome; adiponectin; insulin resistance; HMW-adiponectin
4.  Altered distribution of adiponectin isoforms in children with Prader–Willi syndrome (PWS): association with insulin sensitivity and circulating satiety peptide hormones 
Clinical endocrinology  2007;67(6):944-951.
Summary
Objective
Prader–Willi syndrome (PWS) is a genetic syndrome characterized by relative hypoinsulinaemia and normal or increased insulin sensitivity despite profound obesity. We hypothesized that this increased insulin sensitivity is mediated by increased levels of total and high molecular weight adiponectin and associated with changes in levels of satiety hormones.
Design, patients and measurements
We measured total adiponectin and its isoforms [high molecular weight (HMW), middle molecular weight (MMW) and low molecular weight (LMW) adiponectin] and satiety hormones in 14 children with PWS [median age 11.35 years, body mass index (BMI) Z-score 2.15] and 14 BMI-matched controls (median age 11.97 years, BMI Z-score 2.34).
Results
Despite comparable BMI Z-scores and leptin levels, the PWS children exhibited lower fasting insulin and HOMA-IR (homeostasis model assessment of insulin resistance) scores compared to obese controls. For any given BMI Z-score, the PWS children showed higher concentrations of fasting total and HMW adiponectin and higher HMW/total adiponectin ratios. The HMW/total adioponectin ratio was preserved in children with PWS at high degrees of obesity. In PWS children, fasting plasma total adiponectin, HMW adiponectin and HMW/total adiponectin ratio correlated negatively with age (P < 0.05), HOMA-IR (P < 0.01), BMI Z-score (P < 0.05), insulin (P < 0.01) and leptin (P < 0.05). In addition to higher fasting ghrelin concentrations, the PWS children showed significantly higher fasting levels of total peptide YY (PYY) and gastric inhibitory polypeptide (GIP) compared to obese controls.
Conclusions
Relative to controls of similar age and BMI Z-score, the PWS children had significantly higher levels of total and HMW adiponectin, and increased ratios of HMW/total adiponectin. These findings may explain in part the heightened insulin sensitivity of PWS children relative to BMI-matched controls.
doi:10.1111/j.1365-2265.2007.02991.x
PMCID: PMC2605973  PMID: 17666087
5.  Adiponectin, Leptin, and Resistin in Asthma: Basic Mechanisms through Population Studies 
Journal of Allergy  2013;2013:785835.
Adipokines, factors produced by adipose tissue, may be proinflammatory (such as leptin and resistin) or anti-inflammatory (such as adiponectin). Effects of these adipokines on the lungs have the potential to evoke or exacerbate asthma. This review summarizes basic mechanistic data through population-based and clinical studies addressing the potential role of adipokines in asthma. Augmenting circulating concentrations of adiponectin attenuates allergic airway inflammation and airway hyperresponsiveness in mice. Murine data is supported by human data that suggest that low serum adiponectin is associated with greater risk for asthma among women and peripubertal girls. Further, higher serum total adiponectin may be associated with lower clinical asthma severity among children and women with asthma. In contrast, exogenous administration of leptin results in augmented allergic airway hyperresponsiveness in mice. Alveolar macrophages obtained from obese asthmatics are uniquely sensitive to leptin in terms of their potential to augment inflammation. Consistent with this basic mechanistic data, epidemiologic studies demonstrate that higher serum leptin is associated with greater asthma prevalence and/or severity and that these associations may be stronger among women, postpubertal girls, and prepubertal boys. The role of adipokines in asthma is still evolving, and it is not currently known whether modulation of adipokines may be helpful in asthma prevention or treatment.
doi:10.1155/2013/785835
PMCID: PMC3832971  PMID: 24288549
6.  Adipokines, Insulin Resistance and Coronary Artery Calcification 
Objectives
We evaluated the hypothesis that plasma levels of adiponectin and leptin are independently but oppositely associated with coronary calcification (CAC), a measure of subclinical atherosclerosis. In addition, we assessed which biomarkers of adiposity and insulin resistance are the strongest predictors of CAC beyond traditional risk factors, the metabolic syndrome and plasma C-reactive protein (CRP).
Background
Adipokines are fat-secreted biomolecules with pleiotropic actions that converge in diabetes and cardiovascular disease.
Methods
We examined the association of plasma adipocytokines with CAC in 860 asymptomatic, non-diabetic participants in the Study of Inherited Risk of Coronary Atherosclerosis (SIRCA).
Results
Plasma adiponectin and leptin levels had opposite and distinct associations with adiposity, insulin resistance and inflammation. Plasma leptin was positively (top vs. bottom quartile) associated with higher CAC after adjusting for age, gender, traditional risk factors and Framingham Risk Scores (FRS) [tobit regression ratio 2.42 (95% CI 1.48–3.95, p=0.002)] and further adjusting for metabolic syndrome and CRP [ratio 2.31 (95% CI 1.36–3.94, p=0.002)]. In contrast, adiponectin levels were not associated with CAC. Comparative analyses suggested that levels of leptin, IL-6 and sol-TNFR2 as well as HOMA-IR predicted CAC scores but only leptin and HOMA-IR provided value beyond risk factors, the metabolic syndrome and CRP.
Conclusion
In SIRCA, while both leptin and adiponectin levels were associated with metabolic and inflammatory markers, only leptin was a significant independent predictor of CAC. Of several metabolic markers, leptin and the HOMA-IR index had the most robust, independent associations with CAC.
Condensed Abstract
Adipokines are fat-secreted biomolecules with pleiotropic actions and represent novel markers for cardiovascular risk. We examined the association of plasma adipocytokines with CAC in 860 asymptomatic, non-diabetic Caucasians. Leptin was positively (top vs. bottom quartile) associated with higher CAC even after adjustment for age, gender, traditional risk factors, Framingham Risk Score, metabolic syndrome, and CRP [ratio 2.31 (95% CI 1.36–3.94, p=0.002)]. Adiponectin levels were not associated with CAC. Comparative analyses suggested that levels of leptin, IL-6 and sol-TNFR2 as well as HOMA-IR predicted CAC scores, but only leptin and HOMA-IR provided value beyond risk factors, the metabolic syndrome and CRP.
doi:10.1016/j.jacc.2008.04.016
PMCID: PMC2853595  PMID: 18617073
Adiponectin; Leptin; Coronary Artery Calcification; Atherosclerosis; Inflammation
7.  Ovarian HMW adiponectin is associated with folliculogenesis in women with polycystic ovary syndrome 
Background
Adiponectin may regulate ovarian steroidogenesis, folliculogenesis and ovulation. The alterations in the distribution of adiponectin multimers in follicular fluid (FF) and the relationship between adiponectin multimers and folliculogenesis in women with polycystic ovary syndrome (PCOS) remain unclear. In this study, we aimed to investigate the association between the levels of total and high molecular weight (HMW) adiponectin in serum and FF and folliculogenesis in women undergoing in vitro fertilisation (IVF).
Methods
This prospective study included ten Chinese women with PCOS and ten controls undergoing IVF. The levels of the total and HMW adiponectin in serum and FF were determined by ELISA. Insulin resistance (IR) was estimated using the homeostasis model assessment insulin resistance index (HOMA-IR).
Results
After controlling for the body mass index (BMI), the levels of the total, and the HMW adiponectin in the serum and FF were significantly lower in the women with PCOS compared with the normovulatory women undergoing IVF (P < 0.05). The levels of the HMW adiponectin were significantly lower in the FF than in the serum (P < 0.01). No significant differences were found in the total adiponectin levels in the serum and in the FF (P > 0.05). Decreased HMW adiponectin in the FF was associated with an increased number of follicles and decreased follicular diameters in the normovulatory and PCOS women, and this association was independent of the overall adiposity. A strong positive linear correlation was observed between the number of the follicles and the IR estimated by HOMA-IR (r = 0.784, P < 0.0001). We found that the larger follicular diameters had a negative relationship with the IR estimated by HOMA-IR (r = −0.445, P < 0.05). A strong negative linear correlation was observed between HOMA-IR and the HMW adiponectin levels (r = −0.726, P < 0.001) and the total adiponectin levels (r = −0.759, P < 0.001) in the FF.
Conclusions
The levels of the total adiponectin and the HMW adiponectin in the FF and serum were decreased in the Chinese women with PCOS compared with the normovulatory women undergoing IVF, and the differences persisted after controlling for the BMI. Ovarian HMW adiponectin is negatively correlated to folliculogenesis.
doi:10.1186/1477-7827-11-99
PMCID: PMC4015744  PMID: 24144083
Polycystic ovary syndrome; Adiponectin multimers; Follicular fluid; In vitro fertilisation; Folliculogenesis
8.  Carboxylation of Osteocalcin Affects Its Association With Metabolic Parameters in Healthy Children 
Diabetes Care  2009;33(3):661-663.
OBJECTIVE
Osteocalcin (OC), a bone-derived protein, was recently shown to regulate metabolic pathways in mice. Undercarboxylated OC (ucOC), but not carboxylated OC (cOC), increases adiponectin and insulin secretion. It is unclear if carboxylation of OC affects its association with metabolic parameters in humans.
RESEARCH DESIGN AND METHODS
The associations between ucOC, cOC, total and high-molecular-weight (HMW) adiponectin, and insulin secretion (homeostasis model assessment [HOMA]-β) were investigated in a population-based sample of healthy prepubertal children (n = 103; 49 boys and 54 girls).
RESULTS
Weight-dependent associations were observed between the different forms of OC and metabolic parameters. Higher cOC was related to lower HMW adiponectin (with a stronger association in leaner children; P < 0.001). Higher ucOC-to-cOC ratio was associated with higher HOMA-β (P < 0.01) in leaner children and associated with higher HMW adiponectin (P < 0.001) in heavier children.
CONCLUSIONS
In a weight-dependent manner, cOC and the proportion of ucOC are differentially related to HMW adiponectin and insulin secretion in healthy children.
doi:10.2337/dc09-1837
PMCID: PMC2827527  PMID: 20009098
9.  Total and High-Molecular Weight Adiponectin in Women with the Polycystic Ovary Syndrome 
Objective
Adiponectin, an adipokine with antidiabetic properties, forms multimers, and the high molecular weight (HMW) form most closely correlates with insulin sensitivity. Therefore, we hypothesize that HMW adiponectin levels are decreased in women with polycystic ovary syndrome (PCOS), a condition characterized by insulin resistance, compared to normal controls, and that HMW adiponectin correlates with testosterone and insulin sensitivity.
Design and patients
Cross-sectional study involving 13 women with PCOS and 13 age- and BMI-matched normal controls.
Measurements
Waist-to-hip ratios (WHR), glucose, insulin, SHBG, total testosterone, total and HMW adiponectin levels were measured after an overnight fast. Free testosterone was calculated from SHBG and total testosterone, and insulin sensitivity (Si) was determined using a frequently sampled intravenous glucose tolerance test. The study’s primary outcomes were differences in total and HMW adiponectin between women with PCOS and normal control women.
Results
Total adiponectin (p<0.01), HMW adiponectin (p<0.01), and the ratio of HMW to total adiponectin (SA) (p=0.03), were lower in women with PCOS compared to normal women. Total and HMW adiponectin levels correlated inversely with WHR (p<0.01) and free testosterone (p<0.01) and positively with Si (p<0.001). Using forward stepwise multivariate analysis, HMW adiponectin and WHR, but not PCOS status, were independent predictors of Si.
Conclusions
Women with PCOS have lower total and HMW adiponectin levels compared with normal women. HMW adiponectin also comprises a smaller proportion of total circulating adiponectin in women with PCOS. Alterations in HMW adiponectin levels in women with PCOS may contribute to the insulin resistance intrinsic to the syndrome.
doi:10.1016/j.metabol.2010.02.019
PMCID: PMC2946975  PMID: 20359725
adiponectin multimers; insulin sensitivity; testosterone; visceral adiposity
10.  Associations of adipokines & insulin resistance with sex steroids in patients with breast cancer 
Background & objectives:
Several studies have suggested an important, but conflicting and controversial role for adipose tissue mass in breast cancer risk. Factors such as insulin-like growth factors, sex steroids, adipokines and obesity-related inflammatory markers have been postulated as potential effectors of the mechanisms by which obesity and associated metabolic disorders influence breast cancer risk. In this study we evaluated the associations between obesity indices, insulin resistance, circulating adipokines, sex steroids and breast cancer.
Methods:
Fasting adiponectin, leptin, insulin resistance (homeostasis model assessment, HOMA-IR), testosterone, estradiol, sex hormone binding globulin (SHBG), LH and FSH were determined in 144 newly-diagnosed histologically confirmed breast cancer patients and 77 controls. Univariate and multivariate regression analyses were used to find the associations of these variables with each other, indices of obesity and with breast cancer.
Results:
BMI, waist circumference, HOMA-IR and leptin were significantly (P<0.001) higher in patients than in controls. Adiponectin level was also significantly (P<0.05) higher in patients compared to controls. Adiponectin and leptin showed significant correlations with insulin and HOMA-IR but only adiponectin was significantly correlated with estradiol and SHBG. Logistic regression analyses showed that factors associated with breast cancer were BMI [OR (95% CI) =2.8 (1.4-5.5), P=0.004]; high levels of adiponectin [5.1 (2.2-11.5), P<0.001); hyperinsulinaemia [1.1 (1.0-1.1), P=0.01], leptin [3.1 (1.7-5.7), P<0.0001], estradiol [2.5 (1.3-4.7), P=0.005] and testosterone [1.3 (1.03-1.7), P=0.03].
Interpretation & conclusions:
Our findings confirm that adipokines, insulin resistance and sex steroids are associated with breast cancer. The paradoxical association of increased adiponectin with breast cancer is a novel finding that deserves further investigation.
PMCID: PMC3385233  PMID: 22664497
Adipokines; breast cancer; obesity; sex steriods
11.  Change of Body Composition and Adipokines and Their Relationship with Insulin Resistance across Pubertal Development in Obese and Nonobese Chinese Children: The BCAMS Study 
A transient increase in insulin resistance (IR) is a component of puberty. We investigated the impact of body composition and adipokines on IR during puberty in Chinese children. This study included 3223 schoolchildren aged 6–18 years. IR was calculated using homeostasis model assessment (HOMA-IR). We revealed that body mass index (BMI) and waist circumference increased gradually during puberty in both genders, while fat-mass percentage (FAT%) increased steadily only in girls. Change of leptin showed striking sexual dimorphisms: in girls leptin increased steadily during puberty, whereas in boys, after a transient rise at the beginning of puberty, leptin declined by Tanner staging even in those overweight or obese. Inversely, adiponectin level decreased significantly during puberty. In both genders, HOMA-IR started to increase at the beginning of puberty, peaked in the middle, and revised at late puberty in overweight/obesity boys while it stayed high till the end of puberty in girls and normal weight boys. Multivariate regression analysis revealed that leptin presented a stronger indicator of HOMA-IR than anthropometric measures during puberty. Our results demonstrated that gender-specific FAT% and leptin changed with pubertal development. Leptin emerged as a stronger predictor of IR than traditional anthropometric indices, suggesting a prominent role in the development of pubertal IR.
doi:10.1155/2012/389108
PMCID: PMC3534211  PMID: 23316228
12.  Circulating 25-Hydroxyvitamin D Concentrations Are Correlated With Cardiometabolic Risk Among American Black and White Adolescents Living in a Year-Round Sunny Climate 
Diabetes Care  2012;35(5):1133-1138.
OBJECTIVE
Low vitamin D status is common among healthy black and white adolescents residing at southern U.S. latitudes with a year-round sunny climate. Thus we aimed to study the relationships between circulating 25-hydroxyvitamin D [25(OH)D] and cardiometabolic risk factors in this population.
RESEARCH DESIGN AND METHODS
25(OH)D concentrations were measured with liquid chromatography tandem mass spectroscopy in 701 girls and boys (14–18 years old, 54% blacks, 49% females). Cardiometabolic risk was indexed by adipokines, inflammatory markers, fasting glucose, homeostatic model assessment-insulin resistance (HOMA-IR), lipid profile, and blood pressure (BP).
RESULTS
Controlling for age, sex, race, sexual maturation, season, physical activity, and percent body fat, 25(OH)D concentrations were significantly correlated with adiponectin (r = 0.06, P = 0.05), leptin (r = −0.32, P < 0.01), fibrinogen (r = −0.05, P = 0.03), glucose (r = −0.16, P = 0.02), HOMA-IR (r = −0.17, P < 0.01), HDL cholesterol (r = 0.14, P = 0.02), systolic BP (r = −0.10, P = 0.02), and diastolic BP (r = −0.21, P < 0.01). When 25(OH)D concentrations were stratified into increasing tertiles, there were significant linear upward trends for adiponectin (P = 0.01) and HDL cholesterol (P = 0.04), but significant linear down trends for glucose (P < 0.01), HOMA-IR (P < 0.01), and systolic BP (P < 0.01), after adjusting for the above covariates.
CONCLUSIONS
Circulating 25(OH)D concentrations are associated with various adverse cardiometabolic risk factors, independent of adiposity. Clinical trials addressing the effects of vitamin D supplementation on cardiometabolic risk are warranted in adolescents irrespective of their geographical regions.
doi:10.2337/dc11-1944
PMCID: PMC3329810  PMID: 22410810
13.  Circulating adiponectin levels are lower in Latino versus non-Latino white patients at risk for cardiovascular disease, independent of adiposity measures 
Background
Latinos in the United States have a higher prevalence of type 2 diabetes than non-Latino whites, even after controlling for adiposity. Decreased adiponectin is associated with insulin resistance and predicts T2DM, and therefore may mediate this ethnic difference. We compared total and high-molecular-weight (HMW) adiponectin in Latino versus white individuals, identified factors associated with adiponectin in each ethnic group, and measured the contribution of adiponectin to ethnic differences in insulin resistance.
Methods
We utilized cross-sectional data from subjects in the Latinos Using Cardio Health Actions to reduce Risk study. Participants were Latino (n = 119) and non-Latino white (n = 60) men and women with hypertension and at least one other risk factor for CVD (age 61 ± 10 yrs, 49% with T2DM), seen at an integrated community health and hospital system in Denver, Colorado. Total and HMW adiponectin was measured by RIA and ELISA respectively. Fasting glucose and insulin were used to calculate the homeostasis model insulin resistance index (HOMA-IR). Variables independently associated with adiponectin levels were identified by linear regression analyses. Adiponectin's contribution to ethnic differences in insulin resistance was assessed in multivariate linear regression models of Latino ethnicity, with logHOMA-IR as a dependent variable, adjusting for possible confounders including age, gender, adiposity, and renal function.
Results
Mean adiponectin levels were lower in Latino than white patients (beta estimates: -4.5 (-6.4, -2.5), p < 0.001 and -1.6 (-2.7, -0.5), p < 0.005 for total and HMW adiponectin), independent of age, gender, BMI/waist circumference, thiazolidinedione use, diabetes status, and renal function. An expected negative association between adiponectin and waist circumference was seen among women and non-Latino white men, but no relationship between these two variables was observed among Latino men. Ethnic differences in logHOMA-IR were no longer observed after controlling for adiponectin levels.
Conclusions
Among patients with CVD risk, total and HMW adiponectin is lower in Latinos, independent of adiposity and other known regulators of adiponectin. Ethnic differences in adiponectin regulation may exist and future research in this area is warranted. Adiponectin levels accounted for the observed variability in insulin resistance, suggesting a contribution of decreased adiponectin to insulin resistance in Latino populations.
doi:10.1186/1472-6823-11-13
PMCID: PMC3141565  PMID: 21736747
14.  Comprehensive analysis of circulating adipokines and hsCRP association with cardiovascular disease risk factors and metabolic syndrome in Arabs 
Background
Cardiovascular diseases (CVD) are a leading cause of death worldwide including the Middle East. This is caused in part by the dysregulation of adipose tissue leading to increased production of pro-inflammatory adipokines and reduction in cardio-protective adipokines such as adiponectin. Ethnicity has been recognized as a major factor in the association between CVD risk factors and the different circulating adipokines. In this study, for the first time, the relationship between traditional cardiovascular risk factors, Metabolic Syndrome (MetS) and circulating level of adipokines in Arab ethnicity was investigated.
Methods
We conducted a population-based cross-sectional survey on 379 adult Arab participants living in Kuwait. Traditional cardiovascular risk factors such as blood pressure (BP), low density lipoprotein (LDL) and triglyceride (TG) were measured. Plasma levels of circulating Leptin, Plasminogen Activator Inhibitor (PAI-1) visfatin, adiponectin, resistin and adipsin were assessed using the multiplexing immunobead-based assay.
Results
Circulating levels of High sensitivity C-Reactive Protein (hsCRP), Leptin, PAI-1 and adiponectin were significantly higher in Arab women than men (p < 0.0001). In multi-variate analysis, the homeostasis model assessment-insulin resistance (HOMA-IR) and body mass index (BMI) showed strong association with most of the biomarkers (p < 0.05). HsCRP showed significant association with all risk factors (p < 0.05). Leptin, PAI-1 and adipsin showed significant positive correlation with BMI, unlike adiponectin which showed inverse correlation (p < 0.05). Subjects in the highest tertile of leptin, PAI-1 and hsCRP had higher odds of having Metabolic Syndrome (MetS) (odd ratio [OR] = 3.02, 95% confidence interval [CI] = 1.47 – 6.19) and (OR = 2.52, 95% CI = 1.45 – 4.35), (OR = 4.26, 95% CI = 2.39 – 7.59) respectively. On the other hand subjects with highest tertile of adiponectin had lower odds of having MetS (OR = 0.22, 95% CI = 0.12 – 0.40). Leptin, PAI-1 and hsCRP showed significant positive association with increased MetS components (P-trend <0.05), while adiponectin was negatively associated with increased MetS components (P-trend <0.0001).
Conclusion
Our results show positive association between hsCRP, leptin, PAI-1 with increased MetS components and increase the odds of having MetS. Adiponectin on the other hand showed inverse correlation with MetS components and associated with reduction in MetS. Overall, our data highlights the significant clinical value these markers have in MetS especially hsCRP which can be used as good marker of low grade inflammation in Arabs.
doi:10.1186/1475-2840-13-76
PMCID: PMC3997236  PMID: 24716628
Adipokine; Arab; Metabolic syndrome; Cardiometabolic risk factors; Lipid profile; hsCRP; Leptin; Adiponectin; Visfatin; Resistin; Adipsin; Low grade inflammation
15.  High-Molecular-Weight and Total Adiponectin Levels and Incident Symptomatic Peripheral Artery Disease in Women: A Prospective Investigation 
Circulation  2011;124(21):2303-2311.
Background
Adiponectin is linked to reduced diabetes risk and may be anti-atherogenic, yet clinical data show no consistent relationship with incident cardiovascular events, especially among women. To our knowledge, no prior prospective studies have evaluated adiponectin, including high-molecular-weight (HMW) adiponectin, and incident peripheral artery disease (PAD).
Methods & Results
We evaluated the relationship of total, HMW and the HMW-to-total adiponectin ratio with incident symptomatic PAD in a prospective, nested case-control study conducted within the Women’s Health Study (n=110 cases, n=230 controls, frequency matched in strata defined by five-year age categories, smoking, fasting status and follow-up time; median cohort follow-up=13.2 yrs). Baseline median levels of HMW and total adiponectin were significantly lower in women developing PAD than those remaining event-free(HMW: 3.3 vs. 3.8 μg/mL, P=0.0005; total: 5.6 vs. 7.4 μg/mL, P<0.0001). The ratio did not differ significantly between groups. Age-adjusted PAD odds ratios (95% CI) across tertiles were 1.0, 0.66 (0.39–1.13) and 0.40 (0.22–0.74)for HMW and 1.0, 0.74 (0.43–1.25) and 0.35 (0.18–0.65) for total adiponectin (P-trend=0.004 and 0.001, respectively). Results were similar after adjustment for traditional cardiovascular risk factors, use of post-menopausal hormone therapy, high-sensitivity C-reactive protein, soluble intercellular adhesion molecule-1, leptin, hemoglobin A1c and fasting insulin [adjusted OR and 95% CI for HMW: 1.0, 0.62 (0.29–1.34), 0.30 (0.12–0.74); total: 1.0, 0.46 (0.22–1.00), 0.30 (0.12–0.76 );Ptrend=0.01 for both].
Conclusion
Total and HMW adiponectin are inversely associated with incident PAD among initially healthy women. These prospective data support a protective role for this adipokine in peripheral atherosclerosis development.
doi:10.1161/CIRCULATIONAHA.111.045187
PMCID: PMC3256987  PMID: 22025604
adiponectin; biomarker; epidemiology; peripheral artery disease; women
16.  Adiponectin Is Inversely Associated With Intramyocellular and Intrahepatic Lipids in Obese Premenopausal Women 
Obesity (Silver Spring, Md.)  2010;19(5):911-916.
Adiponectin, an adipokine secreted by adipocytes, exerts beneficial effects on glucose and lipid metabolism and has been found to improve insulin resistance by decreasing triglyceride content in muscle and liver in obese mice. Adiponectin is found in several isoforms and the high-molecular weight (HMW) form has been linked most strongly to the insulin-sensitizing effects. Fat content in skeletal muscle (intramyocellular lipids, IMCL) and liver (intrahepatic lipids, IHL) can be quantified noninvasively using proton magnetic resonance spectroscopy (1H-MRS). The purpose of our study was to assess the relationship between HMW adiponectin and measures of glucose homeostasis, IMCL and IHL, and to determine predictors of adiponectin levels. We studied 66 premenopausal women (mean BMI 31.0 ± 6.6 kg/m2) who underwent 1H-MRS of calf muscles and liver for IMCL and IHL, computed tomography (CT) of the abdomen for abdominal fat depots, dual-energy X-ray absorptiometry (DXA) for fat and lean mass assessments, HMW and total adiponectin, fasting lipid profile and an oral glucose tolerance test (homeostasis model assessment of insulin resistance (HOMAIR), glucose and insulin area under the curve). There were strong inverse associations between HMW adiponectin and measures of insulin resistance, IMCL and IHL, independent of visceral adipose tissue (VAT) and total body fat. IHL was the strongest predictor of adiponectin and adiponectin was a predictor of HOMAIR. Our study showed that in premenopausal obese women HMW adiponectin is inversely associated with IMCL and IHL content. This suggests that adiponectin exerts positive effects on insulin sensitivity in obesity by decreasing intracellular triglyceride content in skeletal muscle and liver; it is also possible that our results reflect effects of insulin on adiponectin.
doi:10.1038/oby.2010.296
PMCID: PMC3607306  PMID: 21151017
17.  High-molecular-weight adiponectin and anthropometric variables among elementary schoolchildren: a population-based cross-sectional study in Japan 
BMC Pediatrics  2012;12:139.
Background
Studies about the relationship between high-molecular-weight adiponectin (HMW-adn) and anthropometric variables among population-based elementary schoolchildren have been too limited, especially in Japan, where blood collection is not usually performed in the annual health examination at elementary schools. The objective of the present study was to investigate the relationship between HMW-adn and anthropometric variables (body mass index [BMI], percent body fat [%BF], waist circumference [WC], and waist-to-height ratio [WHtR]) among population-based elementary schoolchildren in Japan.
Methods
Subjects comprised all fourth-grade schoolchildren (9 or 10 years of age) in the town of Ina, Saitama Prefecture, Japan during 2005–2008 (N = 1675). After excluding 21 subjects because of refusal to participate or incomplete data, data from a total of 1654 subjects (846 boys and 808 girls) were analyzed. The height, weight, %BF, and WC of each subject were measured, while blood samples were drawn from the subjects to measure adiponectin levels (HMW-adn and total adiponectin). Childhood obesity was determined according to the age- and sex-specific cut-off points proposed by the International Obesity Task Force. Spearman’s correlation coefficients between adiponectin levels and anthropometric variables were calculated for each sex.
Results
The anthropometric variables were negatively correlated with HMW-adn in both boys and girls. Correlation coefficients of HMW-adn with anthropometric variables in the obesity group were consistently higher than those in the non-obesity group among both boys and girls. In addition, only WHtR was significantly correlated with HMW-adn regardless of sex and physique (obesity or non-obesity); the correlation coefficient was -0.386 among boys and -0.543 among girls in the obesity group, while it was -0.124 among boys and -0.081 among girls in the non-obesity group.
Conclusions
HMW-adn was negatively correlated with anthropometric variables, while the correlation coefficients of HMW-adn with anthropometric variables in the obesity group were consistently higher than those in the non-obesity group. Moreover, only WHtR was significantly associated with HMW-adn regardless of sex and physique. The results of this study suggested that it is useful to monitor WHtR as a surrogate for HMW-adn among elementary school students, especially obese children.
doi:10.1186/1471-2431-12-139
PMCID: PMC3478987  PMID: 22937905
High-molecular-weight adiponectin; Anthropometric variable; Obesity; Waist-to-height ratio; Children
18.  Obesity-related hormones and endometrial cancer among postmenopausal women: a nested case–control study within the B~FIT cohort 
Endocrine-related cancer  2013;20(1):151-160.
Endometrial cancer risk is strongly influenced by obesity, but the mechanisms of action remain unclear. Leptin and adiponectin, secreted from adipose tissue, reportedly play a role in such carcinogenic processes as cell proliferation, angiogenesis, and insulin regulation. In this case–control study, nested within the Breast and Bone Follow-up of the Fracture Intervention Trial (n = 15 595), we assessed pre-diagnostic serum leptin, total adiponectin, and high-molecular-weight (HMW) adiponectin in relation to endometrial cancer among postmenopausal women. During the 10-year follow-up, 62 incident endometrial cases were identified and matched to 124 controls on age, geographical site, time of fasting blood draw at baseline (1992–1993), and trial participation status. Adipokines and C-peptide were measured by ELISA. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated via conditional logistic regression, with exposures categorized in tertiles (T). Multivariable models considered C-peptide, BMI (kg/m2), and estradiol (E2) as potential confounders. Endometrial cancer risk was significantly associated with higher leptin levels, adjusted for E2 and C-peptide (ORT3 vs T1 = 2.96; 95% CI, 1.21–7.25; P trend <0.01). After further adjustment for BMI, the estimates were attenuated and the positive trend was no longer statistically significant (ORT3 vs T1 = 2.11; 95% CI, 0.69–6.44; P trend = 0.18). No significant associations were observed with adiponectin or HMW adiponectin and endometrial cancer. Our findings with leptin suggest that the leptin–BMI axis might increase endometrial cancer risk through mechanisms other than estrogen-driven proliferation. Continued exploration of these pathways in larger prospective studies may help elucidate mechanisms underlying observed obesity–endometrial cancer associations.
doi:10.1530/ERC-12-0229
PMCID: PMC4038326  PMID: 23222000
endometrial cancer; adiponectin; leptin; obesity
19.  The Effects of Macronutrient Intake on Total and High Molecular Weight Adiponectin: Results from the OMNI-Heart Trial 
Obesity (Silver Spring, Md.)  2009;18(8):1632-1637.
Higher levels of the adipocyte-specific hormone adiponectin have been linked to increased HDL and lower insulin resistance. This study was conducted to determine the influence of macronutrient intake on adiponectin levels. One hundred and sixty-four pre- and stage-1 hypertensive adults participated in OMNI-Heart, a cross-over feeding study originally testing the effects of macronutrients on blood pressure. Participants underwent three 6-week feeding periods: one rich in carbohydrates (CARB), one rich in monounsaturated fat (MUFA), and one rich in protein (PROT), while maintaining body weight. Their median plasma high molecular weight (HMW) and total adiponectin levels were 2.3 and 8.2 μg/ml, respectively, resulting in an average of 27% HMW adiponectin. Both HMW and total adiponectin levels decreased after baseline while the percent HMW adiponectin remained unchanged. Between diets, the MUFA diet maintained a higher level of both HMW and total adiponectin level than either the CARB (HMW: +6.8%, p=0.02; total: +4.5%, p=0.001) or PROT (HMW: +8.4%, p=0.003; total: +5.6%, p<0.001) diets. Changes in total adiponectin levels were positively correlated to changes in HDL cholesterol irrespective of diets (Spearman r = 0.22–0.40). No correlation was found between changes in lipids, blood pressure, or insulin resistance (HOMA-IR). Macronutrient intake has effects on HMW and total adiponectin levels independent of weight loss. A diet rich in monounsaturated fat was associated with higher levels of total and HMW adiponectin in comparison to a carbohydrate- or protein- rich diet. Effects seen in adiponectin paralleled those found with HDL cholesterol.
doi:10.1038/oby.2009.402
PMCID: PMC3045829  PMID: 19876001
adiponectin; cholesterol; diet; obesity
20.  Association of Plasma Retinol-Binding Protein 4, Adiponectin, and High Molecular Weight Adiponectin with Insulin Resistance in Non-Diabetic Hypertensive Patients 
Yonsei Medical Journal  2010;51(3):375-384.
Purpose
The aim of this study was to determine whether retinol-binding protein 4 (RBP4), adiponectin and high molecular weight (HMW) adiponectin are associated with insulin resistance (IR) and metabolic parameters in non-diabetic hypertensive patients. Also, we sought to compare the predictive values of these adipocytokines for IR in non-diabetic hypertensive patients.
Materials and Methods
Analyses of RBP4, adiponectin, and HMW adiponectin were performed on 308 non-diabetic hypertensives (148 males, age 58 ± 10 years, 189 non-metabolic syndrome and 119 metabolic syndrome). The homeostasis model assessment (HOMA) index for IR, lipid profiles, and anthropometric measure-ments were assessed.
Results
There was no significant difference in RBP4 levels according to the presence of metabolic syndrome, although adiponectin and HMW adiponectin were significantly lower in metabolic syndrome. Correlation analysis of log RBP4 with IR and metabolic indices revealed that there was no significant correlation of RBP4 with waist circumference (r = 0.056, p = 0.324), HDL cholesterol (r = 0.005, p = 0.934), ApoB/ApoAI ratio (r = 0.066, p = 0.270), and the HOMA index (r = 0.017, p = 0.756). However, adiponectin and HMW adiponectin showed significant correlations with the HOMA index (r = - 0.247, p < 0.001; r = - 0.296, p < 0.001) and metabolic parameters. With IR defined as HOMA index ≥ 2.5, HMW adiponectin did not demonstrate a superior predictive value for IR compared to adiponectin (AUC = 0.680 vs. 0.648, p = 0.083). The predictive value of RBP4 for IR was minimal (AUC = 0.534).
Conclusion
RBP4 was not associated with IR or metabolic indices and the predictive value for IR was minimal in hypertensives. HMW adiponectin didn't have a superior predictive value for IR compared to adiponectin. Therefore, we can suggest that RBP4 and HMW adiponectin don't have more additive information than adiponectin in non-diabetic hypertensives.
doi:10.3349/ymj.2010.51.3.375
PMCID: PMC2852793  PMID: 20376890
Retinol-binding proteins; adiponectin; hypertension; insulin resistance
21.  Major components of metabolic syndrome and adiponectin levels: a cross-sectional study 
Background
Adiponectin is a major regulator of glucose and lipid homeostasis by its insulin sensitizer properties. Since decreased insulin sensitivity is linked to metabolic syndrome (MS), decreased adiponectin levels may be related to its development. The purpose of the study was to investigate the relationship between adiponectin levels and MS.
Methods
Firstly, we cross-sectionally examined subjects with or without MS submitted to an oral glucose tolerance test at Hospital de Clínicas de Porto Alegre (n = 172). A replication analysis was performed in subjects (n = 422) undergoing cardiac angiography at Hospital São Paulo. Subchronic inflammation (US-CRP), coagulation marker (fibrinogen), insulin sensitivity and resistance (Matsuda ISI and HOMA-IR) were estimated. Plasma total and high molecular weight (HMW) adiponectin were measured.
Results
Total and HMW adiponectin levels were lower in MS subjects (P < 0.05). Total adiponectin levels were lower in the presence of high waist circumference, low HDL-cholesterol and elevated triglyceride criteria in both samples and by elevated blood pressure and glucose criteria in Porto Alegre. HMW adiponectin levels were lower in the presence of low HDL-cholesterol, elevated triglycerides, and glucose criteria. Total adiponectin levels were positively related with HDL-cholesterol and ISI Matsuda, negatively related with waist circumference, glucose, triglycerides, HOMA-IR, and US-CRP and not related with blood pressure. While adjusting for sex and age, increased adiponectin levels remained associated with a reduced prevalence ratio for MS in both cohorts (P = 0.001).
Conclusions
Adiponectin levels decreased with increasing number of MS criteria, and it is in part determined by its relationship with HDL, triglycerides and abdominal adiposity.
doi:10.1186/1758-5996-6-26
PMCID: PMC3941563  PMID: 24568287
Adiponectin; Metabolic syndrome; Obesity
22.  Effects of TNF-α neutralization on adipocytokines and skeletal muscle adiposity in the metabolic syndrome 
In a prior study, we have shown that tumor necrosis factor (TNF)-α neutralization improves inflammatory markers and total adiponectin in patients with the metabolic syndrome, without improving insulin sensitivity. In this study, we sought to extend our understanding of the effects of TNF-α neutralization in this human model of obesity by investigating the responses of high-molecular-weight (HMW) adiponectin, resistin, leptin, and muscle adiposity to etanercept in patients with the metabolic syndrome. Fifty-six men and women with the metabolic syndrome enrolled in a double-blind randomized placebo-controlled trial. Circulating concentrations of total and HMW adiponectin, resistin, and leptin were determined at baseline and after 4 wk of treatment with etanercept. Muscle adiposity was measured by computed tomography (CT). Although etanercept increased total adiponectin concentration, the HMW form, which is thought to mediate insulin sensitivity, was unchanged. Thus the ratio of HMW to total adiponectin decreased following etanercept treatment compared with placebo (−0.03 ± 0.03 vs. 0.06 ± 0.03, P = 0.02). Resistin tended to decrease in the etanercept-treated group compared with placebo (−0.6 ± 0.7 vs. 1.2 ± 0.7 ng/ml, P = 0.06), whereas leptin was not altered. Etanercept decreased muscle attenuation on CT [−0.61 ± 0.64 Hounsfield units (HU) vs. 1.54 ± 0.77 HU in placebo, P = 0.04], suggesting an increase in muscle adiposity. Together, these results demonstrate that neutralization of TNF-α in obese humans results in differential effects on critical adipokines and body composition indexes. These findings may help to explain the lack of effect on insulin sensitivity and extend our knowledge of the biological effects of TNF-α neutralization in obesity.
doi:10.1152/ajpendo.00089.2007
PMCID: PMC3196534  PMID: 17374698
tumor necrosis factor-α; adiponectin; resistin; muscle adiposity; metabolic syndrome
23.  Total and high-molecular weight adiponectin and risk of colorectal cancer: the European Prospective Investigation into Cancer and Nutrition Study 
Carcinogenesis  2012;33(6):1211-1218.
Adiponectin—an adipose tissue-derived protein—may provide a molecular link between obesity and colorectal cancer (CRC), but evidence from large prospective studies is limited. In particular, no epidemiological study explored high-molecular weight (HMW) and non-HMW adiponectin fractions in relation to CRC risk, despite them being hypothesized to have differential biological activities, i.e. regulating insulin sensitivity (HMW adiponectin) versus inflammatory response (non-HMW adiponectin). In a prospective, nested case–control study, we investigated whether prediagnostic serum concentrations of total, HMW and non-HMW adiponectin are associated with risk of CRC, independent of obesity and other known CRC risk factors. A total of 1206 incident cases (755 colon and 451 rectal) were matched to 1206 controls using incidence-density sampling. In conditional logistic regression, adjusted for dietary and lifestyle factors, total adiponectin and non-HMW adiponectin concentrations were inversely associated with risk of CRC [relative risk (RR) comparing highest versus lowest quintile = 0.71, 95% confidence interval (CI) = 0.53–0.95, P trend = 0.03 for total adiponectin and RR = 0.45, 95% CI = 0.34–0.61, P trend < 0.0001 for non-HMW adiponectin]. HMW adiponectin concentrations were not associated with CRC risk (RR = 0.91, 95% CI = 0.68–1.22, P trend = 0.55). Non-HMW adiponectin was associated with CRC risk even after adjustment for body mass index and waist circumference (RR = 0.39, 95% CI = 0.26–0.60, P trend < 0.0001), whereas the association with total adiponectin was no longer significant (RR = 0.81, 95% CI = 0.60–1.09, P trend = 0.23). When stratified by cancer site, non-HMW adiponectin was inversely associated with both colon and rectal cancer. These findings suggest an important role of the relative proportion of non-HMW adiponectin in CRC pathogenesis. Future studies are warranted to confirm these results and to elucidate the underlying mechanisms.
doi:10.1093/carcin/bgs133
PMCID: PMC3388489  PMID: 22431719
24.  Age Before Stage: Insulin Resistance Rises Before the Onset of Puberty 
Diabetes Care  2012;35(3):536-541.
OBJECTIVE
Insulin resistance (IR) is associated with diabetes. IR is higher during puberty in both sexes, with some studies showing the increase to be independent of changes in adiposity. Few longitudinal studies have reported on children, and it remains unclear when the rise in IR that is often attributed to puberty really begins. We sought to establish from longitudinal data its relationship to pubertal onset, and interactions with age, sex, adiposity, and IGF-1.
RESEARCH DESIGN AND METHODS
The EarlyBird Diabetes study is a longitudinal prospective cohort study of healthy children aged 5–14 years. Homeostasis model assessment (HOMA-IR), skinfolds (SSF), adiposity (percent fat, measured by dual-energy X-ray absorptiometry), serum leptin, and IGF-1 were measured annually in 235 children (134 boys). Pubertal onset was adduced from Tanner stage (TS) and from the age at which luteinizing hormone (LH) first became serially detectable (≥0.2 international units/L).
RESULTS
IR rose progressively from age 7 years, 3–4 years before TS2 was reached or LH became detectable. Rising adiposity and IGF-1 together explained 34% of the variance in IR in boys and 35% in girls (both P < 0.001) over the 3 years preceding pubertal onset. The contribution of IGF-1 to IR was greater in boys, despite their comparatively lower IGF-1 levels.
CONCLUSIONS
IR starts to rise in mid-childhood, some years before puberty. Its emergence relates more to the age of the child than to pubertal onset. More than 60% of the variation in IR prior to puberty was unexplained. The demography of childhood diabetes is changing, and prepubertal IR may be important.
doi:10.2337/dc11-1281
PMCID: PMC3322712  PMID: 22279034
25.  DYSREGULATION OF MATERNAL SERUM ADIPONECTIN IN PRETERM LABOR 
Objective
Intra-amniotic and systemic infection/inflammation have been causally linked to preterm parturition and fetal injury. An emerging theme is that adipose tissue can orchestrate a metabolic response to insults, but also an inflammatory response via the production of adipocytokines, and that these two phenomenon are interrelated. Adiponectin, an insulin-sensitizing, anti-inflammatory adipocytokine, circulates in multimeric complexes including low-molecular-weight (LMW) trimers, medium-molecular-weight (MMW) hexamers and high-molecular-weight (HMW) isoforms. Each of these complexes can exert differential biological effects. The aim of this study was to determine whether spontaneous preterm labor (PTL) with intact membranes and intra-amniotic infection/inflammation (IAI) is associated with changes in maternal serum circulating adiponectin multimers.
Study design
This cross-sectional study included patients in the following groups: 1) normal pregnant women (n=158); 2) patients with an episode of preterm labor and intact membranes without IAI who delivered at term (n=41); 3) preterm labor without IAI who delivered preterm (n=27); and 4) preterm labor with IAI who delivered preterm (n=36). Serum adiponectin multimers (total, HMW, MMW and LMW) concentrations were determined by ELISA. Non-parametric statistics were used for analyses.
Results
1) Preterm labor leading to preterm delivery or an episode of preterm labor which does not lead to preterm delivery, was associated with a lower median maternal serum concentration of total and HMW adiponectin, a lower median HMW/total adiponectin ratio, and a higher median LMW/total adiponectin ratio than normal pregnancy; 2) among patients with preterm labor, those with IAI had the lowest median concentration of total and HMW adiponectin, as well as the lowest median HMW/total adiponectin ratio; 3) The changes in maternal adiponectin and adiponectin multimers remained significant after adjusting for confounding factors such as maternal age, BMI, gestational age at sampling, and parity.
Conclusion
1) Preterm labor is characterized by a change in the profile of adiponectin multimers concentrations and their relative isoforms. These changes were observed in patients with an episode of preterm labor not leading to preterm delivery, in patients with intra-amniotic inflammation, or in those without evidence of intra-amniotic inflammation; 2) The changes in adiponectin multimer concentrations reported in preterm labor are different from those previously reported in spontaneous labor at term, suggesting that there is a fundamental difference between preterm labor and labor at term; 3) The findings reported herein, provide the first evidence for the participation of adiponectin multimer in preterm parturition. We propose that adiponectins and adipokines in general provide a mechanism to organize the metabolic demands generated by the process of preterm parturition regardless of the nature of the insult (intra-amniotic inflammation or not).
doi:10.1080/14767050902994655
PMCID: PMC3600360  PMID: 19579094
Adiponectin; Adipokines; Pregnancy; High molecular weight (HMW); Medium molecular weight (MMW); Low molecular weight (LMW); Preterm labor; Intra-amniotic infection; Inflammation; Chorioamnionitis; Preterm delivery; Energy Requirements; Energy Expenditure; Preterm Birth; Metabolism; Metaflammation

Results 1-25 (642377)