Copper biomarkers and their relationship with parameters of insulin resistance in obese women.

Some studies have demonstrated the involvement of high concentrations of copper in the manifestation of insulin resistance in individuals with obesity. The objective of this study was to evaluate the copper nutritional status and its relationship with parameters of glycemic control in women with obesity. An observational case-control clinical study involving 203 women aged between 20 and 50 years, divided into two groups: obese (n = 84) and eutrophic (n = 119). Body weight, height and waist, hip and neck circumferences, dietary copper intake, copper biomarkers, determine ceruloplasmin activity and glycemic control parameters were measured. It was observed that women with obesity had higher copper concentrations in plasma and lower concentrations in erythrocytes when compared to the control group. Analysis of glycemic control parameters revealed a statistically significant difference in fasting blood glucose (p < 0.05) between groups. The study identified a significant positive correlation between plasma copper and fasting insulin values and the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) index (p < 0.05). The results of this study demonstrate that obese women have high copper concentrations in plasma and lower concentrations in erythrocytes. Furthermore, the significant positive correlation between plasma copper and fasting insulin and HOMA-IR index suggests the influence of this mineral on glycemic control parameters in obese women.

Copper biomarkers and their relationship with dyslipidemia in women with obesity.

Adipose tissue dysfunction influences the development of dyslipidemias associated with obesity, however, the mechanisms are still unclear. In this sense, the literature highlights the role of copper in cholesterol synthesis, contributing to the increase in concentrations of this lipid fraction and consequently to the manifestation of dyslipidemia. The objective of the study was to investigate the relationship between copper parameters and lipid profile markers in women with obesity. This is a cross-sectional study involving women aged 20 to 50 years divided into a case group (BMI ≥ 35 kg/m2) and a control group (BMI between 18.5 and 24.9 kg/m2). Copper concentrations in plasma and erythrocytes were determined by inductively coupled plasma optical emission spectrophotometry and ceruloplasmin activity by spectrophotometry. The lipid fractions were analyzed according to the enzymatic colorimetric method, using an automatic biochemical analyzer. Participants with obesity had elevated concentrations of copper in plasma and reduced concentrations in erythrocytes compared to the control group, but there was no significant difference in ceruloplasmin activity between the groups. The research does not identify a correlation between copper parameters and serum concentrations of lipid fractions, which does not allow inferring the role of copper in the manifestation of dyslipidemia in obesity.

Magnesium, selenium and zinc deficiency compromises antioxidant defense in women with obesity.

Studies have shown that deficiencies in magnesium, selenium, and zinc in individuals with obesity compromise the endogenous antioxidant defense system. This study aimed to evaluate the impact of mineral deficiency on enzymatic antioxidant defense in women with obesity. The study involved 63 women with obesity (BMI ≥ 35 kg/m2) and 77 eutrophic women (BMI between 18.5 and 24.9 kg/m2). Variables such as fasting glucose, glycated hemoglobin, fasting insulin, and serum lipids were analyzed. Insulin resistance was measured using the homeostasis assessment model (HOMA-IR) and beta cell function using the homeostasis assessment model (HOMA-ß). Dietary intake of energy, macronutrients (including magnesium, zinc, and selenium), and plasma, erythrocyte, and urinary concentrations of these minerals were measured and analyzed. Serum cortisol, plasma leptin, plasma thiobarbituric acid reactive substances, and the activity of erythrocyte superoxide dismutase (SOD), erythrocyte glutathione peroxidase (GPX), and erythrocyte catalase were also analyzed. Women with obesity had reduced plasma and erythrocyte concentrations and greater urinary excretion of all minerals compared to normal weight women (p < 0.05). There was a positive association between erythrocyte concentrations of zinc and selenium and the activity of the GPX and SOD enzymes in erythrocytes in women with obesity (p < 0.05), in addition to a positive association between serum insulin and the enzyme GPX, which is dependent on dietary selenium (p < 0.05). Individuals with obesity are deficient in magnesium, selenium, and zinc, which appears to impair the antioxidant defense system and contribute to important metabolic disorders such as oxidative stress in these patients.

Relationship Between Zinc, Selenium, and Magnesium Status and Markers of Metabolically Healthy and Unhealthy Obesity Phenotypes.

Our objective was to investigate the relationship between zinc, selenium, and magnesium status and markers of metabolically healthy and unhealthy obesity phenotypes. This was a cross-sectional study with 140 women: metabolically healthy obese women (n = 35), metabolically unhealthy obese women (n = 28), and normal-weight women (n = 77). We have calculated the body mass index, waist-hip ratio, waist-height ratio and some adiposity indices. Additionally, we evaluated endocrine-metabolic parameters and estimated the dietary intake of energy, macronutrients, zinc, selenium, and magnesium. The mineral concentrations in plasma, erythrocytes, and urine were assessed. In obese patients, there was a significant decrease in dietary zinc, selenium, and magnesium intake per kilogram of body weight, as well as lower mineral concentrations in both plasma and erythrocytes. Additionally, these patients exhibited higher urinary mineral levels compared to the control group, regardless of whether they had healthy or unhealthy phenotypes. We observed a significant correlation between deficiencies in zinc, selenium, and magnesium and obesity-associated metabolic disorders, including dyslipidemias and redox status disturbances. This study highlights a connection between deficiencies in zinc, selenium, and magnesium and metabolic disorders linked to obesity, including dyslipidemias, alterations in redox status, and thyroid hormonal dysfunction.

RELATIONSHIP BETWEEN SELENIUM NUTRITIONAL STATUS AND MARKERS OF LOW-GRADE CHRONIC INFLAMMATION IN OBESE WOMEN.

Low-grade chronic inflammation is one of the main disorders that characterize adipose tissue dysfunction in obesity and is an important element in the pathogenesis of several comorbidities. In this context, selenium is an essential micronutrient that exerts important anti-inflammatory functions, and the role of selenium in controlling inflammation associated with obesity is not well defined. Thus, this study aimed to evaluate the relationship between markers of the nutritional status of selenium and low-grade chronic inflammation in obese women. This cross-sectional study included 81 women aged between 18 and 50 years, who were divided into two groups according to body mass index (BMI): the obesity group (n = 38) and normal weight group (n = 43). Selenium intake was assessed by 3-day diet records. The plasma, erythrocyte, and urinary selenium concentrations were determined using inductively coupled plasma optical emission spectrometry. The analysis of serum cytokines interleukin (IL)-8, IL-1ß, IL-6, IL-10, and tumor necrosis factor alpha (TNFα) was performed using flow cytometry. The results of this study revealed that the obese women had higher dietary intake of selenium than eutrophic women. However, obese participants showed decreased selenium concentrations in plasma and erythrocytes, in parallel with increased concentrations of selenium in the urine. Regarding the inflammatory parameters, obese women exhibited higher concentrations of IL-6 and lower concentrations of the cytokines IL-8, IL-1ß, and TNFα than eutrophic women. In the binary logistic regression analysis, erythrocyte selenium was considered an independent predictor of the serum concentrations of cytokine IL-8 in obese women, reflecting the anti-inflammatory action of this micronutrient.

No association between zinc and thyroid activity in obese women.

Obesity is characterized by changes in the metabolism of zinc and thyroid hormones. Studies have also shown the role of zinc in the function and metabolism of thyroid. The present study aimed to evaluate the relationship between serum concentrations of thyroid hormones, dietary zinc intake and zinc distribution in obese women. A case-control study was conducted enrolling 98 women aged between 20 and 50 years old who were divided into case group (BMI ≥ 35 kg/m2) and control group (BMI = 18.5-24.9 kg/m2). Patients underwent anthropometric measurements and analysis of dietary zinc intake, which was performed by a three-day food record. Zinc concentrations in plasma and erythrocytes were determined by inductively coupled plasma optical emission spectrometry. Serum concentrations of thyroid hormones and antibodies were determined by chemiluminescence. Mean values of dietary zinc intake were higher than recommended (10.37 ± 3.12 mg/day and 11.37 ± 4.36 mg/day for control and obeses, respectively). Obese women had reduced plasma (67.22 ± 5.96 µg/dL) and erythrocyte (37.16 ± 3.64 µg Zn/gHb) zinc concentrations when compared to the control group (plasma: 89.71 ± 13.33 µg/dL; erythrocyte: 42.68 ± 3.73 µg Zn/gHb) (p < 0.001). Serum TSH (control: 2.62 ± 1.29 µIU/mL; obeses: 3.08 ± 1.13 µIU/mL), Free T3 (control: 2.19 ± 0.63 pg/dL; obeses: 2.09 ± 0.34 pg/dL), and Free T4 (control: 1.12 ± 0.31 ng/dL; obeses: 1.09 ± 0.19 ng/dL) concentrations were within the normal range in both groups, without significant difference between them (p > 0.05). There was no correlation between thyroid hormone concentrations and zinc parameters (p > 0.05). Although obese women presented hypozincemia, they had normal levels of thyroid hormones and no correlation was found between the studied parameters.

Influence of cortisol on zinc metabolism in morbidly obese women.

INTRODUCTION: The accumulation of visceral fat affects the metabolism of hormones and some nutrients, but these mechanisms remain unclear. OBJECTIVE: To assess the influence of cortisol on the metabolism of zinc in morbidly obese women. METHOD: Cross-sectional, case-control study involving 80 women aged between 20 and 59 years. The participants were divided into two groups: experimental (morbidly obese, n = 40) and control (normal weight, n = 40). Zinc concentrations were determined by atomic absorption spectroscopy and serum and urinary cortisol by chemiluminescence method. RESULTS: Zinc intake was significantly different between groups. Mean plasma zinc was lower in obese compared to control group. Mean values for erythrocyte zinc were 44.52 ± 7.84 µg/gHb and 40.17 ± 6.71 µg/gHb for obese and control groups, respectively. Urinary excretion of this mineral was higher in obese compared to control subjects (p < 0.05). Mean values for plasma cortisol were 9.58 ± 4.86 µg/dL for obese and 9.89 ± 5.61 µg/dL for control groups. Mean values for urinary cortisol were 163.00 ± 100.35 µg/dL and 109.71 ± 34.88 µg/dL for obese and control groups, respectively (p > 0.05). The correlation analysis between cortisol and zinc was not significant (p > 0.05). CONCLUSIONS: Obese patients have hypozincemia and high erythrocyte zinc levels. The correlation between zinc parameters and cortisol concentration showed no influence of this hormone on zinc metabolism.