Serum resistin and inflammatory and endothelial activation markers in obese adolescents

Longitudinal associations between cardiovascular biomarkers and metabolic syndrome during puberty: the PUBMEP study

Puberty has been described as a life stage of considerable metabolic risk specially for those with obesity. The low-grade systemic inflammatory status associated with obesity could be one of the connections with metabolic syndrome (MetS). Thus, we aimed to assess the relationship between inflammatory and cardiovascular biomarkers and the development of MetS during puberty. Seventy-five children from the PUBMEP study (33 females), aged 4-18 years, were included. Cardiovascular and inflammatory biomarkers were measured in the prepubertal and pubertal stage, including high-sensitivity C-reactive protein (CRP), leptin, tumor necrosis factor-alpha (TNFα), interleukin 8 (IL8), monocyte chemoattractant protein 1 (MCP-1), total plasminogen activator inhibitor-1 (tPAI), resistin, adiponectin, myeloperoxidase (MPO), and soluble intercellular adhesion molecule-1 (sICAM-1). MetS was diagnosed at each measurement point. Mixed-effects and logistic regressions were performed. Those children with MetS in puberty presented higher prepubertal values of several cardiometabolic biomarkers in comparison to those without MetS (z-score body mass index (zBMI), waist circumference, insulin, HOMA-IR, leptin, and tPAI (p < 0.05)). For prepubertal children with obesity, the odds of developing MetS in puberty were significantly higher in those having high zBMI (OR = 4.27; CI: 1.39-22.59) or high concentrations of tPAI (OR = 1.19; CI: 1.06-1.43).

CONCLUSION

Those with obesity with higher prepubertal tPAI plasma levels had 19% higher odds of having MetS at puberty highlighting the existence of association between MetS, obesity, and inflammation already in puberty. Thus, assessing cardiometabolic and inflammatory status in children with obesity already at prepuberty is key to avoiding future comorbidities.

WHAT IS KNOWN

• Inflammation, metabolic syndrome, and obesity may have their onset in childhood. • Puberty is a life stage characterized for an increased cardiovascular risk.

WHAT IS NEW

• Prepuberty state could be an early indicator of future cardiometabolic risk. • Children with obesity and high total plasminogen have higher odds of future metabolic syndrome.

Obesity cardiomyopathy: evidence, mechanisms, and therapeutic implications

The prevalence of heart failure is on the rise and imposes a major health threat, in part, due to the rapidly increased prevalence of overweight and obesity. To this point, epidemiological, clinical, and experimental evidence supports the existence of a unique disease entity termed “obesity cardiomyopathy,” which develops independent of hypertension, coronary heart disease, and other heart diseases. Our contemporary review evaluates the evidence for this pathological condition, examines putative responsible mechanisms, and discusses therapeutic options for this disorder. Clinical findings have consolidated the presence of left ventricular dysfunction in obesity. Experimental investigations have uncovered pathophysiological changes in myocardial structure and function in genetically predisposed and diet-induced obesity. Indeed, contemporary evidence consolidates a wide array of cellular and molecular mechanisms underlying the etiology of obesity cardiomyopathy including adipose tissue dysfunction, systemic inflammation, metabolic disturbances (insulin resistance, abnormal glucose transport, spillover of free fatty acids, lipotoxicity, and amino acid derangement), altered intracellular especially mitochondrial Ca²⁺ homeostasis, oxidative stress, autophagy/mitophagy defect, myocardial fibrosis, dampened coronary flow reserve, coronary microvascular disease (microangiopathy), and endothelial impairment. Given the important role of obesity in the increased risk of heart failure, especially that with preserved systolic function and the recent rises in COVID-19-associated cardiovascular mortality, this review should provide compelling evidence for the presence of obesity cardiomyopathy, independent of various comorbid conditions, underlying mechanisms, and offer new insights into potential therapeutic approaches (pharmacological and lifestyle modification) for the clinical management of obesity cardiomyopathy.

The effects of physical activity on adipokines in individuals with overweight/obesity across the lifespan: A narrative review

This narrative review summarizes current knowledge on the effects of physical activity (PA) on adipokine levels in individuals with overweight and obesity. Approximately 90 investigations including randomized control, cross-sectional and longitudinal studies that reported on the effects of a single session of PA (acute) or long-term PA (chronic) on adipokine levels in individuals with overweight/obesity were reviewed. The findings support the notion that there is consensus on the benefits of chronic exercise training-regardless of the mode (resistance vs. aerobic), intensity and cohort (healthy vs. diabetes)-on adipokine levels (such as tumour necrosis factor-alpha, interleukin-6, adiponectin, visfatin, omentin-1 and leptin). However, several confounding factors (frequency, intensity, time and type of exercise) can alter the magnitude of the effects of an acute exercise session. Available evidence suggests that PA, as a part of routine lifestyle behaviour, improves obesity complications by modulating adipokine levels. However, additional research is needed to help identify the most effective interventions to elicit the most beneficial changes in adipokine levels in individuals with overweight/obesity.

The Relevance of Single-nucleotide Polymorphism +62 G>A to the Expression of Resistin Gene Affecting Serum Resistin Levels in Metabolic Syndrome in the Egyptian Population

BACKGROUND

Metabolic Syndrome (MS) is a clinical condition consisting of risk factors associated with type two diabetes and developing cardiovascular disease. It has been suggested that resistin is a linkage between obesity, inflammation and type two diabetes. This study aims to investigate whether Resistin Gene (RETN) polymorphism (+62G>A) is linked to MS and resistin levels among the Egyptian population.

METHODS

This study was performed with 310 Egyptian volunteers: 160 MS subjects and 150 controls. Anthropometric parameters and biochemical variables were determined. The RETN +62G>A polymorphism was genotyped by PCR-RFLP technique.

RESULTS

The resistin levels of the MS group were significantly higher than those of the control group. Resistin levels were positively correlated with anthropometric parameters and liver biomarkers in the MS group. According to RETN +62G>A polymorphism, carriers with the A allele (GA/AA) had significantly increased resistin levels than subjects with the GG genotype, consequently, the RETN +62G >A polymorphism was found to be related to MS, biochemical parameters and anthropometric variables.

CONCLUSION

These findings propose that the RETN +62G>A polymorphism has a great impact on the circulating resistin concentrations, and that resistin levels are strongly related to MS. Therefore, this RETN polymorphism is related to the risk of the prevalence of MS in the Egyptians.

Effects of Aerobic Exercises on Serum Levels of Myonectin and Insulin Resistance in Obese and Overweight Women

Background and Aim: Obesity is associated with cardiovascular diseases, metabolic syndrome, and diabetes and insulin resistance. Myonectin is a myokine mostly secreted from skeletal muscles and inversely associated with obesity. The aim of the present study was to evaluate the effects of 8 weeks of aerobic exercises on serum levels of myonectin and insulin resistance in obese and overweight women.

Materials and Methods: Eighty obese women were assigned to exercise (34) and control groups (46). The exercise program comprised three weekly 45-minute sessions of aerobic exercise training for 8 weeks that included running with 50–70% of maximum heart rate (first 2 weeks – 50%; second week – 60%; third week – 65%; and the last 2 weeks by 70% of maximum heart rate). Twenty-four hours before and after the training session, fasting myonectin serum levels were measured. ANCOVA was used to assess differences between the groups.

Results: Serum levels of myonectin in the experimental group increased significantly (P=0.000); however, insulin resistance significantly decreased in the experimental group (P=0.000).

Conclusion: Therefore, considering the role of myonectin in increasing fatty acid uptake, exercise training can play an essential role in decreasing obesity-related diseases and metabolic syndrome; this effect is partly related to the roles of myonectin. Therefore, the use of this type of exercise is recommended to reduce the risk of diseases associated with obesity and metabolic syndrome.

Resistin polymorphims, plasma resistin levels and obesity in Tunisian volunteers

BACKGROUND

Adipose tissue is an important endocrine organ that secretes a number of adipokines, like Resistin (RETN); it's an adipocytes-secreted cytokine and has been proposed as a link between obesity and diabetes. Many resistin gene polymorphisms were described and their implication in obesity was controversial. This study was to investigate the prevalence of single nucleotide polymorphisms (SNPs) in RETN gene 420C/G; 44G/A; 62G/A; 394C/G and 299 G/A and their association with Resistin level and obesity in Tunisian volunteers.

METHODS

We recruited 169 nonobese (mean age=42.16-14.26 years; mean body mass index [BMI]=24.51-3.69 kg/m² ) and 160 obese (mean age=47.86-11.17 years; mean BMI=36-4.78 kg/m² ). Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism. Anthropometric parameters, lipid levels, Glycemia and insulinemia were measured, BMI was calculated and insulinresistance was evaluated with the homeostasis model assessment insulin resistance (HOMA-IR) and resistin level was measured by ELISA. Statistical analyses were performed by SPSS19.0.

RESULTS

After adjustment for confounding parameters; the Odds Ratio (OR) of obesity associated with mutated genotypes at 420C/G compared with normal genotype was as: OR=2.17; 95% CI [1.28-3.68], P=.004. The serum Resistin levels present no significant association with all RETN polymorphisms and it was significantly associated with BMI (P=.047). In our haplotype analysis, one haplotype seems to be protective and one other seems to be the highest risk to obesity.

CONCLUSION

The 420 C/G Polymorphism were associated with obesity and Leptin concentration in our population.

Increased circulating resistin is associated with insulin resistance, oxidative stress and platelet activation in type 2 diabetes mellitus

Resistin is an adipokine that promotes inflammation and insulin resistance by targeting several cells including platelets. We hypothesised that in type 2 diabetes (T2DM), resistin may foster in vivo oxidative stress, thromboxane-dependent platelet activation and platelet-derived inflammatory proteins release, key determinants of atherothrombosis. A cross-sectional comparison of circulating resistin, sCD40L, as a marker of platelet-mediated inflammation, asymmetric dimethylarginine (ADMA), endothelial dysfunction marker, Dickkopf (DKK)-1, reflecting the inflammatory interaction between platelets and endothelial cells, and urinary 8-iso-PGF_2α and 11-dehydro-TxB₂, reflecting in vivo lipid peroxidation and platelet activation, respectively, was performed between 79 T2DM patients and 30 healthy subjects. Furthermore, we investigated the effects of the α-glucosidase inhibitor acarbose and the PPARγ agonist rosiglitazone, targeting hyperglycaemia or insulin resistance, versus placebo, in 28 and 18 T2DM subjects, respectively. Age- and gender-adjusted serum resistin levels were significantly higher in patients than in controls. HOMA (β=0.266, p=0.017) and 11-dehydro-TXB₂ (β=0.354, p=0.002) independently predicted resistin levels. A 20-week treatment with acarbose was associated with significant reductions (p=0.001) in serum resistin, DKK-1, urinary 11-dehydro-TXB₂ and 8-iso-PGF_2α with direct correlations between the change in serum resistin and in other variables. A 24-week rosiglitazone treatment on top of metformin was associated with significant decreases in resistin, DKK-1, 11-dehydro-TXB₂ and 8-iso-PGF_2α, in parallel with HOMA decrease. In conclusion, resistin, antagonising insulin action in part through PPARγ activation, may favour insulin resistance and enhance oxidative stress, endothelial dysfunction and platelet activation. The adipokine-platelet interactions may be involved in platelet insulin resistance and their consequent pro-aggregatory phenotype in this setting.

EFFECT OF PHYSICAL ACTIVITY ON CARDIOMETABOLIC MARKERS IN ADOLESCENTS: SYSTEMATIC REVIEW

ABSTRACT The accumulation of body fat is a major risk factor for cardiometabolic diseases. Obesity can be considered a chronic systemic inflammatory disease in adults and younger people. The control of subclinical inflammation process through the practice of physical activity (PA) can mitigate the effects of risk factors that trigger atherosclerosis that worsens with advancing age. The objective of this study was to conduct a systematic review of the influence of physical activity and/or exercise on cardiometabolic markers and othrer risk factors of cardiovascular disease in adolescents. A systematic review was conducted in electronic databases Scopus, Pubmed, Conchrane Collection and SciELO. The terms used in the search were "cardiovascular diseases AND inflammation AND adolescents AND physical activity OR exercise". A total of 24 original articles were evaluated, being 14 longitudinal and 10 cross-sectional studies. Overall, 16 articles (66.66%) showed that PA, exercise and/or sedentary behavior may have influenced or have been related to the concentration of cardiometabolic markers. All studies that examined lifestyle changes showed reduction of cardiometabolic markers. Some limitations were observed: reduced samples, lack of dietary prescription, evaluation and control of volume and intensity of exercise. Most of the studies analyzed showed that the physical activity could influence and decrease the concentrations of cardiometabolic markers in adolescents. However, studies with representative sample size and precise control in assessing the level of physical activity and/or exercise are required to determine accurately the changes that the more active lifestyle can bring on inflammatory process, as well as other risk factors for cardiometabolic diseases in adolescents.

Adipocytokines in renal transplant recipients

In the last two decades, perceptions about the role of body fat have changed. Adipocytes modulate endocrine and immune homeostasis by synthesizing hundreds of hormones, known as adipocytokines. Many studies have been investigating the influences and effects of these adipocytokines and suggest that they are modulated by the nutritional and immunologic milieu. Kidney transplant recipients (KTRs) are a unique and relevant population in which the function of adipocytokines can be examined, given their altered nutritional and immune status and subsequent dysregulation of adipocytokine metabolism. In this review, we summarize the recent findings about four specific adipocytokines and their respective roles in KTRs. We decided to evaluate the most widely described adipocytokines, including leptin, adiponectin, visfatin and resistin. Increasing evidence suggests that these adipocytokines may lead to cardiovascular events and metabolic changes in the general population and may also increase mortality and graft loss rate in KTRs. In addition, we present findings on the interrelationship between serum adipocytokine levels and nutritional and immunologic status, and mechanisms by which adipocytokines modulate morbidity and outcomes in KTRs.

Association between serum resistin level and outcomes in kidney transplant recipients

Resistin is an adipocytokine that is associated with inflammation, coronary artery disease, and other types of cardiovascular disease among patients with normal kidney function. However, little is known about the association of resistin with outcomes in kidney transplant recipients. We collected socio-demographic and clinical parameters, medical and transplant history, and laboratory data from 988 prevalent kidney transplant recipients enrolled in the Malnutrition-Inflammation in Transplant-Hungary Study (MINIT-HU study). Serum resistin levels were measured at baseline. Associations between serum resistin level and death with a functioning graft over a 6-year follow-up period were examined in unadjusted and adjusted models. The mean±SD age of the study population was 51 ± 13 years, among whom 57% were men and 21% were diabetics. Median serum resistin concentrations were significantly higher in patients who died with a functioning graft as compared to those who did not die during the follow-up period (median [IQR]: 22[15-26] vs. 19[14-22] ng/ml, respectively; P < 0.001). Higher serum resistin level was associated with higher mortality risk in both unadjusted and fully adjusted models: HRs (95% CI): 1.33(1.16-1.54) and 1.21(1.01-1.46), respectively. In prevalent kidney transplant recipients, serum resistin was an independent predictor of death with a functioning graft.

Early Biomarkers of Subclinical Atherosclerosis in Obese Adolescent Girls with Polycystic Ovary Syndrome

OBJECTIVES

Because in obese youth, pulse wave velocity (PWV), an early cardiovascular disease marker, is elevated, we tested if obese girls with polycystic ovary syndrome (OB-PCOS) have higher PWV and carotid intima-media thickness (cIMT) compared with obese girls without PCOS (OB-non-PCOS) and normal-weight girls without PCOS (NW-non-PCOS) and whether PWV and cIMT correlate with inflammatory and circulating endothelial function biomarkers.

STUDY DESIGN

Cross-sectional study of PWV and cIMT in 91 OB-PCOS, 30 obese controls (OB-non-PCOS), and 19 normal-weight controls (NW-non-PCOS). Body composition, blood pressure, fasting glucose, insulin, lipid concentrations, and endothelial function biomarkers were measured. OB-non-PCOS and OB-PCOS underwent 2-hour oral glucose tolerance testing.

RESULTS

PWV was higher in OB-PCOS (664 ± 24 cm/s) and OB-non-PCOS (624 ± 37 cm/s) compared with NW-non-PCOS (468 ± 13 cm/s, P < .001), with no differences in cIMT. Systolic blood pressure, low-density lipoprotein, and non-high-density lipoprotein cholesterol were higher, and high-density lipoprotein cholesterol and indices of insulin sensitivity were lower in OB-PCOS and OB-non-PCOS compared with NW-non-PCOS. Vascular cell adhesion molecule-1 and high-sensitivity C-reactive protein were higher in OB-PCOS compared with NW-non-PCOS. PWV correlated with adiposity (rs = .46), insulin sensitivity index (homeostatic model assessment-insulin resistance rs = .31), systolic blood pressure (rs = .24; P ≤ .003 for all), and free testosterone (rs = .24; P = .03). In multiple regression analysis with PWV as the dependent variable and age, race, body mass index, PCOS, and dysglycemia as independent variables, only body mass index was an independent contributor to the model (r(2) = 0.068, P = .003).

CONCLUSIONS

In adolescent girls, obesity and not PCOS appears to be associated with heightened cardiovascular disease risk. Increased PWV, vascular cell adhesion molecule-1, and high-sensitivity C-reactive protein may be the earliest subclinical atherosclerosis biomarkers in OB-PCOS.

Association of resistin polymorphisms with resistin levels and lipid profile in children

Previous research has found a correlation between resistin and lipid level variations. Polymorphisms in the resistin gene (RETN) could be involved in this relationship, but the results of the different studies are contradictory. The aim of this study was to examine the association between resistin and lipid levels, and to determine whether resistin polymorphisms are associated with resistin levels and lipid profile in prepubertal children and adolescents. The single nucleotide polymorphisms (SNPs) rs1862513 and rs10401670 were analyzed in 442 randomly selected 6- to 8-year-old children and 827 children aged 12-16 years. Anthropometric data were recorded. Lipid profile was determined using standard methods. Serum resistin levels were measured using a multiplexed bead immunoassay. Resistin polymorphisms were determined by TaqMan(®) allelic discrimination assays. A relationship was found between serum levels of resistin and the SNP rs10401670 in 6- to 8-year-old boys. SNP rs10401670 was also related to TC and LDL-cholesterol in 12- to 16-year-old boys and to HDL-C in 12- to 16-year-old girls. SNP rs1862513 was not related to any of the studied variables. Serum resistin levels were significantly and negatively associated with ApoAI levels in 12- to 16-year-old girls. A SNP in the 3'UTR region of RETN (rs10401670) is associated with resistin levels and lipid profile in children, showing different associations depending on age and gender.

Hyperresistinemia is associated with postmenopausal breast cancer

OBJECTIVE

The constellation of obesity, insulin resistance, and serum adipocytokine levels is associated with the risk and prognosis of postmenopausal breast cancer (PBC). Altered secretion of resistin may underlie the association between overweight/obesity and PBC. We thus explored the association of serum resistin with PBC, taking into account established risk factors, including adipokines and anthropometric, metabolic, and inflammatory markers.

METHODS

In a case-control study, we studied 102 postmenopausal women with pathologically confirmed, incident invasive breast cancer and 102 control participants matched on age and time of diagnosis between 2003 and 2010 at the Veterans' Administration General Hospital of Athens (NIMTS Hospital). Serum resistin, adiponectin, leptin, metabolic (homeostasis model assessment score of insulin resistance) and inflammatory (tumor necrosis factor-α, interleukin-6, and high-sensitivity C-reactive protein) parameters, and tumor markers (carcinoembryonic antigen and CA 15-3) were determined.

RESULTS

The mean serum resistin level was significantly higher in case participants than in control participants (P < 0.001) in both univariate and multivariable analyses, adjusting for age, date of diagnosis, education, family history of cancer, use of exogenous hormones, alcohol consumption, smoking status, physical activity, reproductive markers, metabolic markers, anthropometric (body mass index and weight circumference) markers, inflammatory markers, and adipokines (odds ratio, 1.17; 95% CI, 1.03-1.34; P = 0.02). In case participants, resistin level correlated significantly with tumor markers and inflammatory parameters, but not with metabolic and anthropometric variables.

CONCLUSIONS

Further prospective, longitudinal, and mechanistic studies are needed to determine whether hyperresistinemia is involved in the development of PBC or reflects changes during PBC progression and therefore could be used as a biomarker for PBC. Targeting resistin inhibition could be an effective therapeutic strategy in breast cancer by down-regulating the inflammatory microenvironment in breast tissue.

Resistin levels are related to fat mass, but not to body mass index in children

The relationship of resistin levels with obesity remains unclear. The aim of this study was to determine resistin levels in prepubertal children and adolescents and evaluate their association with anthropometric parameters and body composition. The study population included 420 randomly selected 6-8-year-old children and 712 children aged 12-16 years. Anthropometric data were measured and body mass index (BMI) and waist-to-hip and waist-to-height ratios were calculated. Body composition was assessed using an impedance body composition analyzer. Serum resistin levels were determined using a multiplexed bead immunoassay. Resistin levels were not significantly different between sexes. No significant differences in serum resistin concentrations were found between obese, overweight, and normal weight children at any age, and no significant correlations were observed between resistin concentrations and weight or BMI. However, resistin levels showed a significant positive correlation with fat mass in 12-16-year-old children, particularly in girls. In addition to describing serum resistin levels in prepubertal children and adolescents, our study suggests that resistin is related to body fat rather than to BMI in adolescents.

Plasma resistin levels are associated with homocysteine, endothelial activation, and nitrosative stress in obese youths

OBJECTIVE

To evaluate whether serum resistin levels are related to cardiovascular risk in obese children.

DESIGN AND METHODS

Cross-sectional study of 110 children (40 normal weight and 70 severely obese). Clinical and biochemical parameters, including lipid profile, fasting glucose and insulin, and homocysteine, were determined. The levels of adipokines (adiponectin, leptin, and resistin), markers of inflammation (high-sensitivity C-reactive protein (hs-CRP)), endothelial activation (serum concentrations of soluble intercellular and vascular cellular adhesion molecule-1 (sICAM-1, sVCAM-1)), and oxidative/nitrosative stress (malondialdehyde and urinary nitrate/nitrite) were measured.

RESULTS

A partial correlation adjusted by gender, Tanner stage, and body mass index in obese children showed that resistin was significantly related to central obesity (p<0.002), insulin resistance (p<0.005), and homocysteine (p<0.001). No association was found with other metabolic risk factors or hs-CRP levels. Malondialdehyde (p<0.043) and sVCAM-1 (p<0.002) were positively correlated whereas urinary nitrate/nitrite was negatively correlated (p<0.007). In multiple regression analysis homocysteine, sVCAM-1, and urinary nitrate/nitrite remained independent determinants of resistin levels (R(2) adjusted=0.347, p=0.000).

CONCLUSIONS

Resistin could be considered as a promising marker for future cardiovascular disease in obese children.

Adipokines as a link between obesity and chronic kidney disease

Adipocytes secrete a number of bioactive adipokines that activate a variety of cell signaling pathways in central and peripheral tissues. Obesity is associated with the altered production of many adipokines and is linked to a number of pathologies. As an increase in body weight is directly associated with an increased risk for developing chronic kidney disease (CKD), there is significant interest in the link between obesity and renal dysfunction. Altered levels of the adipokines leptin, adiponectin, resistin, and visfatin can decrease the glomerular filtration rate and increase albuminuria, which are pathophysiological changes typical of CKD. Specifically, exposure of the glomerulus to altered adipokine levels can increase its permeability, fuse the podocytes, and cause mesangial cell hypertrophy, all of which alter the glomerular filtration rate. In addition, the adipokines leptin and adiponectin can act on tubular networks. Thus, adipokines can act on multiple cell types in the development of renal pathophysiology. Importantly, most studies have been performed using in vitro models, with future studies in vivo required to further elucidate the specific roles that adipokines play in the development and progression of CKD.

Correcting vitamin D insufficiency improves insulin sensitivity in obese adolescents: a randomized controlled trial

BACKGROUND

Obese adolescents are at a greater risk of vitamin D deficiency because vitamin D is thought to be sequestered by excess adipose tissue. Poor vitamin D status has been associated with a higher prevalence of the metabolic syndrome, type 2 diabetes, or both in adults and adolescents.

OBJECTIVE

The objective was to determine in obese adolescents the efficacy and safety of 4000 IU vitamin D3/d and whether subsequent increased circulating concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with improved markers of insulin sensitivity and resistance and reduced inflammation.

DESIGN

Obese adolescent patients [n = 35; mean ± SD age: 14.1 ± 2.8 y; BMI (in kg/m(2)): 39.8 ± 6.1; 25(OH)D: 19.6 ± 7.1 ng/mL] were recruited from the University of Missouri Adolescent Diabetes and Obesity Clinic and were randomly assigned to receive either vitamin D3 (4000 IU/d) or placebo as part of their standard care. Anthropometric measurements, inflammatory markers (IL-6, TNF-α, C-reactive protein), adipokines (leptin, adiponectin), fasting glucose, fasting insulin, and HOMA-IR values were measured at baseline and at 2 follow-up visits (3 and 6 mo).

RESULTS

After 6 mo, there were no significant differences in BMI, serum inflammatory markers, or plasma glucose concentrations between groups. Participants supplemented with vitamin D3 had increases in serum 25(OH)D concentrations (19.5 compared with 2.8 ng/mL for placebo; P < 0.001), fasting insulin (-6.5 compared with +1.2 μU/mL for placebo; P = 0.026), HOMA-IR (-1.363 compared with +0.27 for placebo; P = 0.033), and leptin-to-adiponectin ratio (-1.41 compared with +0.10 for placebo; P = 0.045). Inflammatory markers remained unchanged.

CONCLUSION

The correction of poor vitamin D status through dietary supplementation may be an effective addition to the standard treatment of obesity and its associated insulin resistance. This trial was registered at clinicaltrials.gov as NCT00994396.

Serum resistin: a biomarker of breast cancer in postmenopausal women? Association with clinicopathological characteristics, tumor markers, inflammatory and metabolic parameters

OBJECTIVE

Previous few studies have shown that resistin is significantly elevated in breast cancer (BC) patients. Therefore, we investigated whether serum resistin could be used as a potential diagnostic and prognostic tool for postmenopausal BC (PBC), taking into account clinicopathological features, serum tumor markers, anthropometric, metabolic, and, for the first time, inflammatory parameters.

METHODS

Serum resistin, tumor markers (CA 15-3 and CEA), metabolic, anthropometric and inflammatory parameters (TNF-α, IL-6, hsCRP) were determined in 103 postmenopausal women with incident, pathologically confirmed, invasive BC, 103 controls matched on age and time of diagnosis, and 51 patients with benign breast lesions (BBL).

RESULTS

Mean serum resistin was significantly higher in cases than in controls and patients with BBL (p<0.001). In patients, resistin was significantly associated with tumor and inflammatory markers, cancer stage, tumor size, grade and lymph node invasion but not with anthropometric, metabolic parameters and hormone receptor status. Multivariable regression analysis revealed that serum IL-6 (p=0.02) and cancer stage (p=0.048) were the strongest determinants of serum resistin in cases adjusting for demographic, metabolic and clinicopathological features. Although resistin's diagnostic performance was low based on ROC curve analysis [0.72, 95% CI: 0.64-0.79], it could, however, represent a BC biomarker reflecting advanced disease stage and inflammatory state.

CONCLUSION

Further prospective and longitudinal studies are needed to evaluate whether serum resistin could be used as a prognostic tool in BC monitoring and management. More research is essential to elucidate resistin's ontological role in the association between obesity, representing a chronic low-grade subclinical inflammation, and PBC.

Correlation of resistin with inflammatory and cardiometabolic markers in obese adolescents with and without metabolic syndrome

OBJECTIVE

The link between plasma resistin and obesity-related cardiometabolic disorders in children remains debatable. This study assessed the relationships of plasma resistin with cardiovascular risk factors, pro-inflammatory markers and insulin resistance index (HOMA-IR) in obese (Ob) adolescents and obese adolescents with metabolic syndrome (Ob-MS) compared to healthy controls (CO).

METHODS

114 obese adolescents (60 Ob, age 13.6 ± 0.9 years, BMI 28.0 ± 2.2 kg/m(2), and 54 Ob-MS, age 13.8 ± 1.0 years, BMI 32.5 ± 4.8 kg/m(2)) and 37 CO (age 13.7 ± 0.8 years, BMI 22.8 ± 0.8 kg/m(2)) were studied. Anthropometrics, cardiac variables as well as fasting plasma concentrations of lipids, glucose, insulin, and adipocytokines (resistin, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP)) were measured. HOMA-IR was calculated, and the presence of MS was assessed.

RESULTS

Plasma resistin was significantly higher in Ob-MS than in both Ob and CO and was correlated with anthropometric, cardiovascular, pro-inflammatory markers and several components of MS as was HOMA-IR in Ob and Ob-MS. With increasing the number of MS components, plasma resistin, pro-inflammatory markers, and HOMA-IR were also increased. Multiple regression models highlighted significant correlation between resistin and both HOMA-IR (r = 0.40, p < 0.05) and systolic blood pressure (r = 0.63, p < 0.01) in Ob-MS.

CONCLUSION

These results support the hypothesis that there is an association between circulating resistin and childhood obesity-related inflammatory and cardiometabolic events.